Apparatus and method for casting a metal article

Information

  • Patent Grant
  • 6698493
  • Patent Number
    6,698,493
  • Date Filed
    Tuesday, July 23, 2002
    23 years ago
  • Date Issued
    Tuesday, March 2, 2004
    22 years ago
Abstract
As a mold containing molten metal is lowered from a heating chamber, a baffle extends around the mold. Force is transmitted from the mold to an inner section of the baffle to release connectors between the inner section of the baffle and an outer section of the baffle. As the connectors are released, a side surface on the inner section of the baffle moves out of the coplanar relationship with a side surface on the outer section of the baffle. The baffle may be integrally formed as one-piece. Rather than being formed as one-piece, the baffle may include separate pieces which form the inner and outer sections of the baffle. Alternatively, the inner section of the baffle may be disposed above and supported by the outer section of the baffle. Latches may be provided to interconnect the outer section of the baffle and the furnace assembly.
Description




BACKGROUND OF THE INVENTION




The present invention relates to an apparatus and method which are used in the casting of a metal article. During withdrawal of a mold for the metal article from a heating chamber of a furnace, a baffle blocks transmission of heat from the heating chamber.




It has been previously been suggested to utilize a baffle to block transmission of heat from a heating chamber of a furnace during withdrawal of a mold from the heating chamber. The use of the baffle minimizes the loss of heat from the heating chamber so that the heating chamber remains at a relatively high temperature and the space below the heating chamber is maintained at a relatively low temperature. This temperature differential promotes solidification of molten metal from a lower end portion of the mold toward an upper end portion of the mold as the mold is withdrawn from the heating chamber.




It has previously been suggested that baffles may be utilized in association with molds to retard the transmission of heat from a heating chamber of a furnace. Various baffle constructions which have previously been suggested are disclosed in U.S. Pat. Nos. 4,108,236; 4,774,992; 4,969,501; and 6,276,432.




SUMMARY OF THE INVENTION




The present invention relates to a new and improved apparatus and method for use in casting a metal article. The apparatus may include a furnace assembly having a heating chamber. A chill plate may be provided to move a mold into and out of the heating chamber. A baffle may be utilized at a lower end portion of the heating chamber to at least partially block heat flow from the heating chamber during withdrawal of the mold from the heating chamber.




The baffle may have an inner section with an opening through which the mold extends when the mold is in the heating chamber. An outer section of the baffle may extend around the inner section of the baffle. A plurality of connectors may extend between the outer and inner sections of the baffle and hold them against movement relative to each other. The connectors may be releasable to enable the inner section of the baffle to move downward relative to an outer section of the baffle to increase the size of an opening through which the mold moves from the heating chamber.




The connectors may extend between the outer and inner sections of the baffle and retain one or more side surfaces on the outer and inner sections of the baffle in a coplanar relationship when the mold is in the heating chamber of the furnace assembly. The connectors may be releasable under the influence of force transmitted from the mold to enable the inner section of the baffle to move downward relative to the outer section of the baffle.




The baffle may be formed as one-piece with the connectors integrally formed as one-piece with the outer and inner sections of the baffle. The connectors may be broken under the influence of force transmitted from the mold to the baffle during lowering of the mold from the heating chamber. If desired, the outer and inner sections of the baffle may be separated by a plurality of slits with the connectors disposed between end portions of the slits and formed of the same material which forms the outer and inner sections of the baffle.




The outer and inner sections of the baffle may be formed as separate pieces. If this is done, the inner section of the baffle may initially be disposed in an opening in the outer section of the baffle and held in its initial position by a plurality of connectors which extend between the outer and inner sections of the baffle. The connectors are releasable to enable the inner section of the baffle to move downward out of the opening in the outer section of the baffle as the mold is moved from the heating chamber of the furnace assembly.




The inner section of the baffle may be disposed above and at least partially supported by the outer section of the baffle. If this is done, the inner section of the baffle may be moved downward through an opening in the outer section of a baffle to increase the size of an opening through which the mold is moved from the heating chamber.




Although the baffle may be connected with a furnace assembly in many different ways, it is believed that it may be desired to utilize latches to connect the baffle with the furnace assembly. The outer section of the baffle may be moved into engagement with and move the latches during movement of the baffle into the heating chamber in the furnace assembly. The latches are effective to retain the outer section of the baffle against downward movement relative to the furnace assembly during movement of the mold out of the heating chamber in the furnace assembly.




The present invention has a plurality of different features which may be used together or separately. One or more of the features of the present invention may be utilized in association with one or more features of the prior art.











BRIEF DESCRIPTION OF THE DRAWINGS




FIG.


1


. is a schematic illustration depicting a relationship of a baffle to a furnace assembly having a heating chamber in which a mold is disposed;




FIG.


2


. is a schematic plan view, taken generally along the line


2





2


of

FIG. 1

, further illustrating the construction of the baffle;




FIG.


3


. is a schematic fragmentary sectional view, taken generally along the line


3





3


of

FIG. 2

, illustrating a slit which is formed in the baffle and separates an outer section of the baffle from an inner section of the baffle;




FIG.


4


. is a fragmentary sectional view, taken generally along the line


4





4


of

FIG. 2

, schematically illustrating the construction of a connector which extends between the outer and inner sections of the baffle;




FIG.


5


. is a fragmentary schematic illustration, generally similar to

FIG. 4

, depicting an alternative construction of the connector which interconnects the inner and outer sections of the baffle;




FIG.


6


. is a fragmentary schematic illustration, generally similar to

FIGS. 4 and 5

, illustrating a baffle having an inner section which is separate from an outer section and the manner in which a connector retains the inner section of the baffle in an opening in the outer section of the baffle;




FIG.


7


. is a fragmentary schematic sectional view, generally similar to

FIGS. 4-6

, illustrating the manner in which adhesive may be utilized to retain a inner section of the baffle in an opening in an outer section of the baffle;




FIG.


8


. is a schematic sectional view, generally similar to

FIGS. 4-7

, illustrating the manner in which a connector member and adhesive may be utilized to hold the inner section of the baffle in an opening in the outer section of the baffle;




FIG.


9


. is a schematic plan view, generally similar to

FIG. 2

, illustrating the manner in which breakable members may be utilized to hold an inner section of a baffle in an opening in an outer section of the baffle;




FIG.


10


. is a fragmentary schematic illustration, generally similar to

FIG. 1

, depicting the manner in which an inner section of a baffle may be disposed above an outer section of a baffle;




FIG.


11


. is a enlarged schematic illustration depicting the manner in which an outer rim portion of the inner section of the baffle of

FIG. 10

is supported by an inner rim portion of the outer section of the baffle;




FIG.


12


. is a fragmentary schematic illustration, generally similar to

FIGS. 1 and 10

, illustrating the manner in which latches may be utilized to retain an outer section of any one of the baffles of

FIGS. 1-11

against downward movement relative to a furnace assembly;




FIG.


13


. is a schematic illustration of one of the latches of

FIG. 12

; and




FIG.


14


. is a schematic illustration of a second embodiment of a latch which may be utilized to hold a baffle against downward movement relative to a furnace assembly.











SPECIFIC PREFERRED EMBODIMENTS OF THE INVENTION




General Description




An apparatus


20


(

FIG. 1

) is used to cast a blade or vane for a turbine engine. However, it should be understood that the apparatus


20


may be utilized to cast many different articles having many different configurations other than the specific configuration illustrated in FIG.


1


. The apparatus


20


includes a furnace assembly


22


.




The illustrated furnace assembly


22


is of the known induction type and includes a cylindrical induction coil


24


. The induction coil


24


extends around a refractory wall


26


of the furnace assembly


22


. A cylindrical radiation liner


28


is provided within the refractory wall


26


. A circular cover


30


is provided at the upper end portion of the refractory wall


26


.




The furnace assembly


22


may be enclosed by a housing. Once a mold


34


has been positioned in the housing on a circular chill plate


36


, an inert atmosphere may be provided in the housing and the housing may be evacuated. The housing may have the same general construction as is disclosed in U.S. Pat. No. 3,841,384. If desired, a fluidized bed and/or housing may be utilized in the manner disclosed in U.S. patent application Ser. No. 09/569,906 filed May 11, 2000 by Graham et al and entitled System For Casting A Metal Article Using A Fluidized Bed. The disclosure from the aforementioned U.S. patent application Ser. No. 09/569,906 is incorporated herein by reference.




When the mold


34


is to be utilized to cast a metal article, such as a turbine engine blade or vane, the cast metal article may be formed of a nickel-chrome super alloy. Of course, the cast article may be formed of a different metal if desired. The molten metal alloy may be solidified in a cavity


40


in the mold


34


with a crystallographic structure which is equiaxed, columnar grain, or single crystal. Although a mold


34


for casting a single article has been illustrated schematically in

FIG. 1

, it is contemplated that the mold


34


could be constructed so as to have two or more article mold cavities


40


. For example the mold


34


may have the construction illustrated in U.S. Pat. Nos. 3,714,977; 4,763,716; or 4,969,501. It is contemplated that the mold


34


, may have any one of many different known constructions and have any desired number of mold cavities.




The molten metal is poured into the mold


34


through a funnel


42


. Once the cavity


40


in the mold


34


has been filled with molten metal, the chill plate


36


is lowered to withdraw the mold from a cylindrical heating chamber


44


in the furnace assembly


22


.




During pouring of the molten metal into the mold


34


and withdrawal of the mold from the furnace assembly, the heating chamber


44


may be maintained at a temperature of approximately 3,000 degrees Fahrenheit. Of course, the temperature in the heating chamber


44


may be different for different metals.




As the mold


34


is withdrawn from the heating chamber


44


, the mold is exposed to a relatively cool environment disposed below the furnace assembly


22


. The molten metal in the mold cavity


40


solidifies upward from a lower end portion


48


of the mold


34


toward an upper end portion


50


of the mold. A solidification front between liquid and solid metal moves upward relative to the mold


34


as the mold is withdrawn from the heating chamber


44


. In order to promote upward solidification of molten metal in the mold cavity


40


a long a generally horizontal solidification front as the mold


34


is withdrawn from the heating chamber


40


, it is advantageous to maintain a relatively large temperature gradiant between the heating chamber


44


and the environment disposed immediately beneath the furnace assembly


22


.




When the mold


34


is constructed so as to have a plurality of mold cavities


40


, the solidification fronts in each of the mold cavities will be at the same level as the mold is withdrawn from the furnace assembly


22


. The solidification fronts in the plurality of mold cavities will move upward from lower end portions of the mold cavities toward the upper end portions of the mold cavities.




Regardless of how many mold cavities


40


are provided in the mold


34


, a baffle


52


is provided at the lower end portion


54


of the heating chamber


44


. The baffle


52


is effective to retard the transmission of heat between the heating, chamber


44


and the environment immediately beneath the furnace assembly


22


. The baffle


52


(

FIG. 2

) has an annular outer section


60


which is connected with the furnace assembly


22


and a circular inner section


62


. The inner section


62


has an opening


64


through which the mold


34


extends. It should be understood that the inner and outer sections of the baffle


52


could have a configuration other than circular.




The opening


64


advantageously has a configuration which corresponds to a cross sectional configuration of the lower end portion


48


of the mold


34


. By forming the opening


64


with a configuration corresponding to the cross sectional configuration of the lower end portion of the mold


34


, the amount of space between the inner section


62


of the baffle


52


and the exterior of the lower end portion


48


of the mold


34


is minimized. By minimizing the space between the exterior of the lower portion


48


of the mold


34


and the inner section


62


of the baffle


52


, the baffle is effective to block radiation of heat from the heating chamber


44


during withdrawal of the lower portion of the mold


34


from the heating chamber.




When the mold


34


is constructed so as to have a plurality of article mold sections, in the manner disclosed in U.S. Pat. Nos. 3,714,977; 4,763,716; and 4,969,501, a plurality of openings


64


may be provided in the inner section


62


of the baffle


52


. There may be a separate opening for each article mold section. Alternatively, a plurality of article mold sections could extend through a single opening


64


in the baffle


52


.




The upper end portion


50


(

FIG. 1

) of the mold


34


has a substantially larger cross sectional configuration than the lower end portion


48


of the mold. Although the lower end portion


48


of the mold


34


can readily move through the opening


64


, the upper end portion


50


of the mold is too large to move through the opening


64


. Therefore, as the chill plate


36


and mold


34


are lowered relative to the furnace assembly


22


, the upper end portion


50


of the mold moves into engagement with the inner section


62


of the baffle


52


. The force applied against the inner section


62


of the baffle


52


is effective to release a plurality of connectors


70


(

FIG. 2

) which interconnect the outer section


60


and inner section


62


of the baffle


52


.




Once the connectors


70


have been released, the inner section


62


of the baffle moves away from the outer section


60


of the baffle and increases the size of the opening in the baffle. The resulting, relatively large opening in the outer section


60


of the baffle can accommodate the upper end portion


50


of the mold


34


. Therefore, during withdrawal of the upper end portion


50


of the mold


34


from the heating chamber


44


, only the outer section


60


of the baffle


52


is effective to block the transmission of heat from the heating chamber


44


. The inner section


62


of the baffle falls downward away from the furnace assembly onto the chill plate


36


which, at this time, is disposed in a substantial distance below the furnace assembly.




One-Piece Baffle




In accordance with one of a plurality of features of the present invention, the baffle


52


may be formed as one-piece. Portions of the outer section


60


, inner section


62


, and connectors


70


of the baffle


52


are all at least partially formed from a single piece of material.




As the mold


34


is withdrawn from the heating chamber


44


, the upper end portion


50


of the mold applies force against the inner section


62


of the baffle


52


. This force is effective to release the connectors


70


.




The force applied against the inner section


62


of the baffle


52


is effective to break the connectors


70


. This may result in the connectors


70


being broken with a tearing action or a snapping action. Once the connectors


70


have been broken to separate the inner section


62


from the outer section


60


of the baffle


52


, the inner section of the baffle falls downward away from the outer section of the baffle. This results in the formation of a relatively large opening in the outer section


60


of the baffle. This opening will have a size and configuration corresponding to the size and configuration of the inner section


62


of the baffle


52


.




In the embodiment of the baffle


52


illustrated in

FIG. 2

, the inner section


62


of the baffle


52


has a circular configuration and the outer section


60


of the baffle has an annular configuration. Therefore, when the connectors


70


are broken to release the inner section


62


of the baffle


52


, a relatively large circular opening is provided in the baffle


52


. The diameter of this relatively large opening is greater than the maximum transverse dimension of the upper end portion


50


of the mold


34


. Therefore, the upper end portion


50


of the mold


34


can readily pass through the opening as the chill plate


36


continues to be lowered.




Although the periphery of the illustrated inner section


62


of the baffle


52


(

FIG. 2

) has been formed with a circular configuration, it is contemplated that the inner section


62


of the baffle could have a different peripheral configuration if desired. For example, the inner section


62


of the baffle


52


could have an outer edge with a configuration corresponding to the cross sectional configuration of the upper end portion


50


of the mold


34


. The outer edge of the inner section


62


of the baffle


52


would be larger in size than the cross sectional size of the upper end portion


50


of the mold


34


to enable the mold to move through an opening formed by separation of the inner section from the outer section


60


of the baffle.




When the inner section


62


of the baffle


52


is separated from the outer section


60


of the baffle by releasing the connectors


70


, the opening which is formed in the outer section


60


of the baffle will be larger than the cross sectional size of the upper end portion


50


of the mold


34


. Therefore, the upper end portion of the mold


34


can be readily moved through the opening which results from separation of the inner section


62


of the baffle


52


from the outer section


60


of the baffle as the chill plate


36


continues to be lowered. The opening which is formed in the outer section


60


of the baffle


52


may have any desired configuration.




As initially formed, the inner section


62


of the one-piece baffle


52


may be separated from the outer section


60


of the baffle by a plurality of slits


74


(FIGS.


2


and


3


). The slits


74


extend between upper and lower major side surfaces


76


and


78


of the baffle


52


(FIG.


3


). The upper major side surface


76


extends parallel to the lower major side surface


78


of the baffle. Although the slits


74


extend perpendicular to the side surfaces


76


and


78


of the baffle


52


, the slits may be skewed relative to the side surfaces of the baffle if desired.




Prior to releasing of the connectors


70


(FIGS.


2


and


4


), the portion of the upper major side surface


76


of the baffle


52


disposed on the inner section


62


and connectors of the baffle is disposed in a coplanar relationship with the portion of the upper major side surface


76


disposed on the outer section


60


of the baffle. Similarly, the portion of the lower major side surface


78


disposed on the inner section


62


and connectors


70


of the baffle


52


is disposed in a coplanar relationship with the portion of the lower major side surface


78


disposed on the outer section


60


of the baffle.




The outer section


60


, inner section


62


and connectors


70


of the one-piece baffle


52


are all at least partially formed from the same piece of material. The single piece of material from which the outer section


60


, inner section


62


, and connectors


70


are all at least partially formed has a circular configuration with a diameter corresponding to the diameter of a circular opening at the lower end portion


54


of the heating chamber


44


(

FIG. 1

) The single piece of material from which the baffle


52


is formed extends from the outer section


60


, through the connectors


70


, to the inner section


62


. Of course, if the lower end portion of the heating chamber


44


had a different configuration, the single piece of material forming the baffle


52


would be cut to have a configuration which is different than the circular configuration illustrated in FIG.


2


.




The outer section


60


, inner section


62


and connectors


70


of the one-piece baffle


52


may all be formed from a single piece of material. Alternatively, the outer section


60


, inner section


62


and/or connectors


70


may be formed of a plurality of pieces which are interconnected to form a baffle


52


having a one-piece construction. However, one of the plurality of pieces of the baffle


52


would form at least a portion of the outer section


60


, inner section


62


and connectors


70


.




The illustrated baffle


52


(

FIGS. 2 and 4

) is entirely formed by a single piece of material which completely forms the outer section


60


, inner section


62


and connectors


70


. Thus, the specific baffle


52


, illustrated in

FIGS. 2-4

, consists of a single undivided piece of material. In the specific embodiment illustrated in

FIG. 2

, the single piece of material is a graphite felt. However, the material may be a ceramic or refractory metal if desired. Of course, the baffle


52


may be formed of other materials.




When the mold


34


is constructed so as to have two or more article mold cavities, in the manner previously mentioned, the inner section


62


of the baffle


52


may have a configuration which is different than the illustrated configuration. For example, the slits


74


may be arranged so as to partially define an opening through which the periphery of gating connected with a plurality of article molds can easily pass. This would enable the mold


34


to be constructed with a plurality of runners extending from a pour cup to each of a plurality of article mold cavities.




The baffle


52


may be provided with one or more radial slits to facilitate positioning the baffle relative to a relatively large base end portion of a mold, in a manner similar to that disclosed in U.S. Pat. No. 4,757,856. The slit or slits to facilitate positioning the baffle


52


relative to a relatively large base end portion of a mold would extend from a radially outer edge of the outer section


60


to the opening


64


in the inner section


62


of the baffle. The slit or slits to facilitate positioning of the baffle relative to a mold may extend through one or more of the connectors to or may be spaced from the connectors. The opening


64


may be configured to have two or more sections to receive end portions of two or more article mold sections of a mold.




In the embodiment of the baffle


52


illustrated in

FIG. 2

, the slits


74


forming the inner section


62


are disposed in a circular array having a center which is coincident with the center of a circular outer rim portion


82


of the outer section


60


of the baffle


52


. The connectors


70


are disposed between end portions of adjacent slits


74


. The connectors


70


are formed with the same thickness and construction as the outer section


60


and inner section


62


of the baffle


52


(FIG.


4


).




Until the connectors


70


are broken to release the inner section


62


of the baffle for movement relative to the outer section


60


of the baffle, there is a continuous uninterrupted body of material extending through the connectors


70


between the outer and inner sections of the baffle. If desired, the connectors


70


may be weakened by indenting or cutting partway through the material of the baffle


52


at the connectors. Regardless of whether or not the connectors


70


are preweakened to facilitate breaking of the connectors, the connectors


70


are formed by material which is one-piece with material forming the outer section


60


and inner section


62


of the baffle


52


.




It is contemplated that the baffle


52


may be formed of many different materials. However, the baffle


52


is formed of a material which is capable of withstanding the relatively high temperatures to which it is exposed as a result of the high temperatures in the heating chambers


44


. The baffle


52


may be formed of graphite, a suitable ceramic, or a suitable refractory metal. It is believed that it may be desired to form the baffle


52


as one-piece composed of one or more layers of graphite felt and/or graphite foil. The graphite felt may be enclosed by layers of graphite foil. Although the baffle


52


would have a multi layered construction, one of the layers of the baffle would form at least a portion of the outer section


60


, inner section


62


, and connectors


70


.




In the embodiment of the invention illustrated schematically in

FIG. 1

, the outer rim portion


82


of the outer section


60


of the baffle


52


is clamped between a base member


86


which supports the furnace assembly


22


and the cylindrical radiation liner


28


. However, the baffle


52


may be mounted in the furnace assembly


22


in any one of many known ways. For example, one or more releasable connectors may be utilized to mount the baffle


52


in the furnace assembly


22


.




After the chill plate


36


has been moved to the raised position illustrated in

FIG. 1

, the cover


30


is removed from the furnace assembly


22


and the mold


34


is positioned in the heating chamber


44


. The lower end portion


48


of the mold extends through the opening


64


in the inner section


62


of the baffle


52


and engages the chill plate


36


. The cover


30


is then replaced. Alternatively, the baffle


52


and mold


34


may both be positioned on the chill plate


36


when the chill plate is in a fully lowered position. The baffle


52


may be positioned on the chill plate


36


with a central axis of the chill plate extending through the opening


64


. The mold


34


may be positioned on the chill plate


36


with a lower end portion


48


of the mold extending through the opening


64


and with the mold and chill plate in a coaxial relationship.




If the mold


34


has a relatively large base plate on flange at a lower end portion


48


of the mold, the baffle


52


may be provided with a slit which extends from the opening


64


in the inner section


62


to a radially outer edge of the rim portion


82


of the outer section


60


of the baffle. This slit allows the baffle


52


to be flexed and positioned around the lower end portion


48


of the mold


34


at a location above the base plate or flange. This would result in the baffle


52


overlying the base plate or flange at the lower end portion of the mold


32


in a manner similar to that disclosed in U.S. Pat. Nos. 3,714,977 and 4,969,501.




Once the baffle


52


has been positioned on the chill plate


36


, the chill plate is raised into the furnace assembly


22


. The baffle


52


is connected with the furnace assembly


22


by a suitable retainer. The retainer may have a construction similar to the construction disclosed in U.S. Pat. No. 4,774,992 or other known construction. Alternatively, latches similar to the latches illustrated in

FIGS. 12-14

herein may be used to connect the baffle


52


with the furnace assembly


22


.




If desired, the baffle


52


may be divided into a plurality of segments in a manner similar to the disclosure in U.S. Pat. No. 4,969,501. If this is done, the segments of the baffle may be interconnected after they have been positioned relative to the mold


34


. Dividing the baffle


52


into segments would facilitate placement of the baffle relative to a complicated mold structure. However, dividing the baffle


52


into segments would complicate construction of the baffle, would increase the time required to position the baffle, and would weaken the baffle. Therefore, unless required by a complicated mold structure, it is believed that it will be preferred to avoid dividing baffle


52


into segments and reconnecting the segments.




After the mold


34


has been preheated to a desired temperature by operation of the furnace assembly


22


, molten metal is poured through the funnel


42


into the mold cavity


62


. After the mold cavity


40


has been filled with molten metal, the chill plate


36


is slowly lowered to withdraw the mold


34


from the heating chamber


44


. As this occurs, the molten metal solidifies with a solidification front which is disposed adjacent to the baffle


52


. Therefore, as the mold


34


is lowered, the solidification front moves upward in the mold cavity


40


toward the upper end portion


50


of the mold. As this occurs, the solidification front remains adjacent to the baffle


52


.




As the mold


34


continues to be lowered from the heating chamber


44


, the relatively large upper end portion


50


of the mold


34


moves into engagement with the portion of the upper major side surface


76


of the baffle


52


disposed adjacent to the opening


64


through the inner section


62


of the baffle. As the chill plate


36


continues to be lowered, force is applied against the upper side of the inner section


62


of the baffle


52


by the upper portion


50


of the mold. This force is transmitted to the connectors


70


. The force transmitted from the mold


34


to the connectors


70


is effective to release the connectors.




Depending upon the characteristics of the material from which the baffle


52


is formed, the connectors


70


may release with a tearing action or with a snapping action. Thus, if the baffle


52


is formed of a flexible graphite felt, the connectors


70


may be broken with a tearing action. Alternatively, if the one-piece baffle


52


is formed of a relatively brittle material, such as a ceramic or a refractory metal, the connectors


70


may be brittle and break with a snapping action.




The one-piece baffle


52


may be formed with a layered construction illustrated in FIG.


5


. If the baffle


52


is formed with a layered construction, the baffle may have a graphite felt inner layer


88


. A graphite foil upper layer


90


may be positioned on and connected to the inner layer


88


. Similarly, a graphite foil lower layer


92


may be positioned on and connected to the inner layer


88


. In the embodiment illustrated in

FIG. 5

, the upper and lower, layers


90


and


92


are cut at


94


and


96


to weaken the connectors


70


at locations disposed between the outer and inner sections of the one-piece baffle


52


. The inner layer


88


forms at least a portion of the outer section


60


, inner section


62


, and connectors


70


. In the embodiment illustrated in

FIG. 5

, the inner layer


88


is coextensive with the outer section


60


, inner section


62


, and connectors


70


.




Once the connectors


70


have been broken, the inner section


62


of the baffle


52


falls downward onto the chill plate


62


. As this occurs, a relatively large opening is formed in the outer section


60


of the baffle. The opening formed in the outer section


60


of the baffle


52


is large enough to enable the upper end portion


50


of the mold to freely move downward through the baffle as the chill plate


36


continues to be lowered.




In the embodiment of the invention illustrated in

FIG. 2

, a circular opening is formed in the center of the outer section


60


of the baffle


52


when the connectors


70


are broken to release the inner section


62


. However, it is contemplated that the slits


74


could have a configuration other than the arcuate configuration illustrated in

FIG. 2

so that the opening formed in the outer section


60


of the baffle


52


would have a configuration which is different than a circular configuration. For example, the opening formed in the outer section


60


of the baffle may have a configuration similar to and slightly larger than the cross sectional configuration of the upper end portion


50


of the mold


34


.




Baffle With Separate Sections and Connectors




In the embodiments of the invention illustrated in

FIGS. 1-5

, the outer section


60


, inner section


62


and connectors


70


of the baffle


52


are all at least partially formed from one-piece of material, for example, the inner layer


88


of FIG.


5


. In the embodiment of the invention illustrated in

FIGS. 6-8

, the outer section, inner section, and connectors for the baffle are formed by separate pieces. Since the embodiment of the invention illustrated in

FIG. 6

are generally similar to the embodiments of the invention illustrated in

FIGS. 1-5

, similar numerals have been utilized to designate similar components, the suffix letter “a” being added to the numerals of

FIG. 6

to avoid confusion.




A baffle


52




a


is utilized in association with a furnace assembly


22


(

FIG. 1

) in the same manner as is the baffle


52


. The baffle


52




a


(

FIG. 6

) includes an annular outer section


60




a


and a circular inner section


62




a


. The circular inner section


62




a


is separate from the annular outer section


60




a


. An opening, corresponding to the opening


64


of

FIG. 1

, is provided in the inner section


60




a.






A circular slit


74




a


separates the outer section


60




a


from the inner section


62




a


The slit


74




a


forms a circular opening in the outer section


60




a


. The inner section


62




a


is disposed in the opening in the outer section


60




a


. If desired, the inner section


62




a


and the slit


74




a


may be formed with a configuration which is a different than a circular configuration. If this was done, the opening in the outer section


60




a


would have a non-circular configuration.




A plurality of connectors


70




a


extend between the outer section


60




a


and the inner section


62




a


and hold the outer and inner sections against movement relative to each other. An upper major side surface


76




a


of the outer section


60




a


is disposed in a coplanar relationship with an upper major side surface


92


on the inner section


62




a


. Similarly, a lower major side surface


78




a


on the outer section


60




a


on the baffle


52




a


is disposed in a coplanar relationship with a lower major side surface


94


on the inner section


62




a.






The connector


70




a


interconnects the outer section


60




a


and inner section


62




a


to maintain the upper major side surfaces


76




a


and


92


of the baffle


52




a


in one plane which extends parallel to a plane in which the lower major side surfaces


78




a


and


94


of the baffle are disposed. The connector


70




a


is formed separately from the outer section


60




a


and inner section


62




a


of the baffle


52




a


. The connector


70




a


is secured to and extends between the outer section


60




a


and inner section


62




a


. The connector


70




a


is formed of a material which is different than the material which forms the outer section


60




a


and inner section


62




a


. However, the outer section


60




a


, inner section


62




a


, and connector


70




a


may be formed of the same material.




The annular outer section


60




a


of the baffle


52




a


extends around the inner section


62




a


of the baffle. Thus, the circular inner section


62




a


is disposed in a circular opening formed in the outer section


60




a


. The outer section


60




a


of the baffle


52




a


may be connected with the furnace assembly


22


in the same manner as illustrated in

FIG. 1. A

plurality of connectors


70




a


transmit force between the outer section


60




a


and inner section


62




a


of the baffle


52




a


to maintain the baffle in the opening in the outer section during withdrawal of the lower portion of the mold from the heating chamber of the furnace assembly.




In the embodiment illustrated in

FIG. 6

, the connector


70




a


is formed separately from the outer section


60




a


and inner section


62




a


. The illustrated connect or


70




a


is a connector member or staple having a leg or end portion


102


which engages the outer section


60




a


of the baffle


52




a


. The connector


70




a


has a leg or end portion


104


which engages the inner section


62




a


of the baffle


52




a


. An intermediate portion


106


extends between the two end portions


102


and


104


and spans the slit


74




a.






In the embodiment of the connector


70




a


illustrated in

FIG. 6

, the two end portions


102


and


104


have longitudinal central axes which extend transverse to a longitudinal central axis of the intermediate portion


106


. Although the end portions


102


and


104


extend perpendicular to the intermediate portion


106


in the illustrated embodiment of the connector


70




a


, it is contemplated that the end portions


102


and


104


could be skewed relative to the intermediate portion


106


and extend toward each other. This would result in the connectors


70




a


being effective to interconnect the outer section


60




a


and the inner section


62




a


of the baffle


52




a


with a clinching action.




The connector


70




a


may be formed of any desired material. For example, the connector


70




a


may be formed of a ceramic material. Alternatively, the connector


70




a


may be formed of a metal capable of withstanding the high temperatures to which it is exposed. Although the intermediate portion


106


of the connector


70




a


has been illustrated in

FIG. 6

as extending along the upper major side surfaces


76




a


and


92


of the baffle


52




a


, it is contemplated that the connector


70




a


could be disposed on the lower side of the baffle.




Positioning the connector


70




a


on the lower side of the baffle


52




a


would result in the connector being disposed adjacent to the chill plate


36


(FIG.


1


). By positioning the connector adjacent to the chill plate


36


, the temperature to which the connector


70




a


is exposed tends to be minimized. If desired, the end portions


102


and


104


could be eliminated from the connector


70




a


and the connector located between the upper major side surfaces


76




a


and


92


and the lower major side surfaces


78




a


and


94


of the baffle


52




a


. If this was done, it may be desired to increase the length of the intermediate portion


106


from the relatively short length illustrated in FIG.


6


.




Regardless of whether the connector


70




a


is disposed adjacent to the upper side of the baffle


52




a


(as illustrated in FIG.


6


), adjacent to the lower side of the baffle, or disposed between upper and lower sides of the baffle, the connector spans the slit


74




a


which separates the outer section


60




a


from the inner section


62




a


of the baffle. By spanning the joint between the outer section


60




a


and inner section


62




a


of the baffle


52




a


, the connector


70




a


is effective to transmit force from the outer section


60




a


of the baffle to the inner section


62




a


of the baffle to hold the inner section of the baffle in the opening in the outer section of the baffle during withdrawal of the lower portion of the mold


34


(

FIG. 1

) from the heating chamber


44


.




The outer section


60




a


consists of a single layer of graphite felt. Similarly, the inner section


62




a


consists of a single layer of graphite felt. However, the outer and inner sections


60




a


and


62




a


may have a different construction if desired. For example, the outer and inner sections


60




a


and


62




a


may have the multilayered construction previously described in conjunction with FIG.


5


.




When a metal article is to be cast in the mold


34


, the baffle


52




a


is mounted in the lower end portion of the heating chamber


44


in the manner previously described in connection with the embodiment of the invention illustrated in

FIGS. 1-5

. The chill plate


36


is moved upward to a position adjacent to the lower side of the baffle


52




a


. The cover


30


(

FIG. 1

) is then removed and the mold


34


positioned on the chill plate. Of course, the mold


34


may be positioned on the chill plate


36


and raised toward the furnace assembly with the chill plate.




Once molten metal has been poured into the mold


34


, the chill plate


36


is slowly lowered. Lowering the chill plate


36


results in the mold


34


being slowly withdrawn from the heating chamber


44


. As the mold


34


is withdrawn from the heating chamber


44


, the molten metal in the mold solidifies at a solidification front which is maintained adjacent to the baffle


52


. This results in the solidification front being displaced upward in the mold cavity


40


as the mold is withdrawn from the heating chamber


44


.




Upon completion of withdrawal of the lower portion


48


of the mold


34


from the heating chamber


44


, the upper end portion


50


of the mold moves into engagement with the upper major side surface


92


(

FIG. 6

) of the inner section


62




a


of the baffle


52




a


. The force applied against the upper major side surface


92


of the inner section


62




a


of the baffle


52




a


is effective to release the connectors


70




a


. The inner section


62




a


of the baffle


52




a


then drops downward onto the chill plate


36


. This results in the formation of a relatively large opening in the stationary outer section


60




a


of the baffle


52




a


. As the chill plate


36


continues to be lowered, the upper end portion


50


of the mold


34


moves through the relatively large opening created by separating the inner section


62




a


of the baffle


52




a


from the outer section


60




a


of the baffle.




As the upper end portion


50


of the mold


34


moves into initial engagement with the inner section


62




a


of the baffle


52




a


, the mold applies a downward force against the upper major side surface


92


of the inner section


62




a


. This force is effective to move the inner section


62




a


downward relative to the stationary outer section


60




a


of the baffle


52




a


. As this occurs, the inner section


62




a


of the baffle slides along the end portion


104


of the connector


70




a


. As the inner section


62




a


continues to move downward and out of the circular opening formed in the outer section


60




a


of the baffle


52




a


, the end portion


104


of the connector


70




a


and the inner section


62




a


of the baffle are separated to release the baffle for downward movement onto the chill plate under the influence of gravity.




Although the specific connector


70




a


, illustrated in

FIG. 6

, is released by being disengaged from the inner section


62




a


, the connector could be released in a different manner if desired. For example, the connector


70




a


could be deformed and/or torn from the outer section


60




a


or inner section


62




a


. The connector


70




a


may be constructed so as to break at the intermediate portion


106


of the connector to release the inner section


62




a


of the baffle


52




a.






Although only a single connector


70




a


has been illustrated schematically in

FIG. 6

, it should be understood that there are a plurality of identical connectors


70




a


. The plurality of connectors


70




a


span the slit


74




a


tat spaced apart locations along the slit. The number of connector members


70




a


utilized to interconnect the outer section


60




a


and inner section


62




a


of the baffle


52




a


will be a function of the weight of the inner section


62




a


of the baffle. Thus, the greater the weight of the inner section


62




a


of a baffle, the greater the number of connectors


70




a


which will be utilized. For example, four connectors


70




a


may be positioned at spaced apart locations between the outer section


60




a


and inner section


62




a


of the baffle


52




a


in much the same manner as in which four connectors


70


are positioned in FIG.


2


. However, a greater or lesser number of connectors


70




a


may be utilized if desired.




In the embodiment of the invention illustrated in

FIG. 6

, a connector member extends along outer surfaces of the baffle


52




a


. Thus, the connector member


70




a


extends along the upper major side surfaces


76




a


and


92


of the baffle. However, the connector member


70




a


may extend along the lower major side surfaces


78




a


and


94


of the baffle.




In the embodiment of the invention illustrated in

FIG. 7

, a connector is positioned in a joint between outer and inner sections of the baffle. Since the embodiment of the invention illustrated in

FIG. 7

is generally similar to the embodiments of the invention illustrated in

FIGS. 1-6

, similar numerals will be utilized to identify to similar components, the suffix letter “b” being associated with the numerals of

FIG. 7

to avoid confusion.




A baffle


52




b


has an outer section


60




b


which is connected with an inner section


62




b


by a connector


70




b


. In the embodiment of the invention illustrated in

FIG. 7

, the connector


70




b


is located in a circular slit


74




b


between the annular outer section


60




b


and circular inner section


62




b


of the baffle. The connector


70




b


is disposed in the slit


74




b


between a plane containing an upper major side surface


76




b


of the outer section


60




b


and an upper major side surface


92




b


of the inner section


62




b


of the baffle and a plane containing a lower major side surface


78




b


on the outer section


60




b


and a lower major side surface


94




b


on the inner section


62




b


of the baffle


52




b


. Although the connector


70




b


is disposed entirely within the slit


74




b


, it is contemplated that a portion of the connector


70




b


could extend upward and/or downward from the slit.




The connector


70




b


transmits force between the outer section


60




b


and inner section


62




b


of the baffle


52




b


to support the inner section


62




b


of the baffle. The circular inner section


62




b


of the baffle is disposed in a circular opening formed in the annular outer section


60




b


of the baffle. The upper major side surfaces


76




b


and


92




b


of the baffle are disposed in a coplanar relationship., Similarly, the lower major side surfaces


78




b


and


94




b


of the baffle are disposed in a coplanar relationship. An opening, corresponding to the opening


64


of

FIG. 2

, is provided in the inner section


62




b


of the baffle


52


.




The connector


70




b


is formed by one or more bodies of adhesive. The adhesive of the connector


70




b


is connected to an annular inner rim portion


110


of the outer section


60




b


of the baffle


52




b


. The adhesive of the connector


70




b


is also connected to an annular outer rim portion


112


of the inner section


62




b


of the baffle


52




b


. This enables force to be transmitted through the adhesive forming the connector


70




b


to hold the inner section


62




b


of the baffle in an opening formed in the outer section


60




b


of the baffle


52




b.






The connector


70




b


may be formed by a plurality of relatively small bodies or dots of adhesive which are disposed in the slit


74




b


between the outer section


60




b


and inner section


62




b


of the baffle


52




b


. Alternatively, the connector


70




b


may be formed by an annular ring of adhesive which is coextensive with the slit


74




b


. Of course, a plurality of spaced apart elongated bodies of adhesive may be provided rather than small dots or a single body of adhesive.




The outer section


60




b


consists of a single layer of graphite felt. Similarly, the inner section


62




b


consists of a single layer of graphite felt. However, the outer and inner sections


60




b


and


62




b


may have different construction if desired. For example, the outer and inner sections


60




b


and


62




b


may have the multilayered construction previously described in conjunction with FIG.


5


.




When the baffle


52




b


is mounted on the lower end portion of the furnace assembly


22


, in the same manner as is illustrated schematically for the baffle


52


in

FIG. 11

, force is transmitted through the adhesive of the connector


70




b


to hold the inner section


62




b


in the circular opening formed in the outer section


60




b


of the baffle. As the mold


34


is withdrawn from the heating chamber


44


(FIG.


1


), the upper end portion


50


of the mold moves into engagement with inner section


62




b


of the baffle


52




b


and applies force against the inner section of the baffle.




The force applied by the upper end portion


50


of the mold


34


against the inner section


62




b


of the baffle


52




b


is effective to release the connector


70




b


. This may be done tearing the material of the baffle


52




b


adjacent to the adhesive forming the connector


70




b


or by breaking the adhesive material itself. Once the connector


70




b


has been released, the inner section


62




b


of the baffle


52




b


is free to fall downward onto the chill plate


36


. The upper end portion


50


of the mold


34


can then be moved through the relatively large opening formed by disconnecting the inner section


62




b


of the baffle from the outer section


60




b


of the baffle.




In the embodiment of the invention illustrated in

FIG. 6

, the connector


70




a


is formed by a member which extends between the outer and inner sections


60




a


and


62




a


of the baffle


52




a


. In the embodiment of the invention illustrated in

FIG. 7

, the connector is formed by adhesive which extends between the outer section


60




b


and inner section


62




b


of the baffle


52




b


. In the embodiment of the invention illustrated in

FIG. 8

, the connector is formed by both a member and a body of adhesive which extend between the outer section and the inner section of the baffle. Since the embodiment of the invention listed in

FIG. 8

is generally similar to the embodiments of the invention illustrated in

FIGS. 1-7

, similar numerals will be utilized to designate similar components, the suffix letter “c” being associated with the numerals of

FIG. 8

to avoid confusion.




A baffle


52




c


(

FIG. 8

) includes an annular outer section


60




c


and a circular inner section


62




c


. An opening corresponding to the opening


64


of

FIG. 1

, is formed in the inner section


62




c


(FIG.


8


). The outer and inner sections


60




c


and


62




c


are separated by circular slit


74




c.






A connector


70




c


spans to slit


74




c


. The connector


70




c


is effective to hold the inner section


62




c


in a circular opening formed in the outer section


60




c


of the baffle. An upper major side surface


76




c


on the outer section


60




c


of the baffle


52




c


is disposed in a coplanar relationship with an upper major surface


92




c


on the inner section


62




c


of the baffle. Similarly, a lower major side surface


78




c


on the outer section


60




c


of the baffle


52




c


is disposed n a coplanar relationship with a lower major side surface


94




c


on the inner section


62




c


of the baffle.




The connector


70




c


is formed by a connector member


120


which spans the slit


74




c


and a body


122


of adhesive. The body


122


of adhesive connects the connector member


120


to the outer section


60




c


and inner section


62




c


of the baffle


52




c.






The connector member


120


may be flexible and formed of a material which can withstand relatively high temperatures, such as a graphite cloth. The connector member


120


may be tape. Alternatively, the connector member


120


may be formed of a rigid material, such as a ceramic or refractory material. Regardless of whether the connector member


120


is flexible or rigid, it is connected with both the outer section


60




c


and the inner section


62




c


of the baffle


52




c


by the body


122


of adhesive.




The body


122


of adhesive may have a configuration corresponding to a configuration of the connector member


120


. Thus, the connector member


120


may be formed by an elongated strip or rod and the body


122


may be an elongated strip of adhesive. Although only one connector member


120


and body


122


of adhesive are illustrated in

FIG. 8

, it should be understood that there are a plurality of connector members and bodies of adhesive arranged in a circular array along the slit


74




c.






Alternatively, the connector member


120


may have an annular configuration and be coextensive the slit


74




c


. If this is done, the body


122


of adhesive would have an annular configuration and be coextensive with the slit


74




c.






The connector member


120


and body


122


of adhesive are illustrated in

FIG. 8

as being disposed adjacent to the upper side surfaces


76




c


and


92




c


of the outer and inner sections


60




c


and


62




c


of the baffle


52




c


. However, the connector member


120


and body


122


of adhesive may be disposed adjacent to the lower side surfaces


78




c


and


94




c


of the outer and inner sections


60




c


and


62




c


of the baffle


52




c


. This would result in the connector


70




c


being exposed to the relatively cool chill plate


36


.




The outer section


60




c


consists of a single layer of graphite felt. Similarly, the inner section


62




c


consists of a single layer of graphite felt. However, the outer and inner sections


60




c


and


62




c


may have a different construction if desired. For example, the outer and inner sections


60




c


and


62




c


may have the multilayered construction previously described in conjunction with FIG.


5


.




Connector Rods




In the embodiments of the invention illustrated in

FIGS. 6-8

, the connectors


70




a


,


70




b


, and


70




c


extend between the outer sections and inner sections of the baffles. In the embodiment of the invention illustrated in

FIG. 9

, the connectors extend from one portion of the outer section of the baffle, along the inner section of the baffle, to another portion of the outer section of the baffle. Since the embodiment of the invention illustrated in

FIG. 9

is generally similar to the embodiments of the invention illustrated in

FIGS. 1-8

, similar numerals will be utilized to designate similar components, the suffix letter “d” being associated with the numerals of

FIG. 9

to avoid confusion.




A baffle


52




d


has an annular outer section


60




d


and a circular inner section


62




d


. The outer section


60




d


and inner section


62




d


are separated by a circular slit


74




d


. A connector


70




d


supports the circular inner section


62




d


in a circular opening


130


formed in the annular outer section


60




d.






When the inner section


62




d


is disposed in the opening


130


in the outer section


60




d


, an upper side surface of the outer section


60




d


is disposed in a coplanar relationship with an upper side surface of the inner section


62




d


. Similarly, a lower side surface of the outer section


60




d


is disposed in a coplanar relationship with an outer side surface of an inner section


62




d


in the manner previously explained in conjunction with the embodiments of the invention illustrated in

FIGS. 6-8

. In the embodiments of the invention illustrated in

FIGS. 6-9

both upper side surfaces of the inner and outer sections of the baffle and lower side surfaces of the inner and outer sections of the baffle are disposed in a coplanar relationship. However, it is contemplated that only the upper side surfaces of the inner and outer sections of the baffle may be disposed in a coplanar relationship. Alternatively, only the lower side surfaces of the inner and outer sections of the baffle may be disposed in a coplanar relationship.




The connector


70




d


includes a plurality of elongated members or rods


134


and


136


. The rods


134


and


136


extend in a chordal manner across the circular opening


130


in the outer section


60




d


and are spaced from an opening


64




d


in the inner section


62




d


. Thus, the left (as viewed in

FIG. 9

) end portion


140


of the connector member or rod


134


is disposed in engagement with one portion of the outer section


60




d


. A right (as viewed in

FIG. 9

) end portion


142


of the connector member


134


is disposed in engagement with another portion of the outer section


60




d


. An intermediate portion


144


of the connector member or rod


134


is disposed in engagement with the inner section


62




d


and forms a chord to the circular opening


130


. The intermediate portion


144


of the connector member or rod


134


is spaced from the opening


64




d


in the inner section


62




d.






Similarly, the connector member or rod


136


includes a left (as viewed in

FIG. 9

) end portion


148


which is disposed in engagement with a portion of the outer section


60




d


of the baffle


52




d


. A right (as viewed in

FIG. 9

) end portion


150


of the connector member or rod


136


is disposed in engagement with another portion of the outer section


60




d


. An intermediate portion


152


of the rod extends across the opening


130


in the outer section


60




d


in a chordal manner. The connector member or rod


136


is spaced from the opening


64




d


. Since the connector members or rods


134


and


136


are spaced from the opening


64




d


in the inner section


62




d


, the mold


34




d


can be positioned in the opening


64




d


without interference with the connector members or rods.




In the embodiment of the invention illustrated in

FIG. 9

, the connector members or rods


134


and


136


are disposed in engagement with lower side surfaces of the outer section


60




d


and inner section


62




d


. The connector members or rods


134


and


136


support the outer section


60




d


and inner section


62




d


with their lower side surfaces in a coplanar relationship. The outer section


60




d


and inner section


62




d


have the same thickness. Therefore, the upper side surfaces of the outer section


60




d


and inner section


62




d


are disposed in a coplanar relationship. The connector members or rods


134


and


136


have longitudinal central axes which extend parallel to the upper and lower major side surfaces of the outer section


60




d


and inner section


62




d


of the baffle


52




d.






The left and right end portions


140


and


142


of the connector member or rod


134


rest on the base member


86


(

FIG. 1

) at a location beneath the outer section


60




d


. Similarly, the left and right end portions


148


and


150


of the connector member or rod


136


rest on the base member


86


at locations beneath the outer section


60




d


. The connector members or rods


134


and


136


span the circular opening


130


. This enables the connector members or rods


134


and


136


to support the inner section


62




d


of the baffle


52




d


in the circular opening


130


.




The end portions


140


,


142


,


148


and


150


of the connector members or rods


134


and


136


rest on a flat upper surface of the base member


86


(FIG.


1


). However, it is contemplated that it may be desired to provide notches in the base member


86


to locate the connector members or rods


134


and


136


relative to the base member.




When the baffle


52




d


is to be installed in the furnace assembly


22


(

FIG. 1

) the connector members or rods


134


and


136


are positioned on the base member


86


. To facilitate positioning of the connector members or rods


134


and


136


, the base member


86


may include a removable ring on which the rods rest. Alternatively, the cover


30


and radiation liner


28




b


may be removed from the furnace assembly


22


and the connector members or rods


134


and


136


positioned on the base


86


.




Once the connector members or rods


134


and


136


have been positioned on the base member


86


, the outer section


60




d


of the baffle


52




d


is positioned on the connector members or rods


134


and


136


. The inner section


62




d


is then positioned on the intermediate portions


144


and


152


of the connector members or rods


134


and


136


. This enables the connector members or rods


134


and


136


to support the inner section


62




d


in the circular opening


130


. The radiation liner


28


may then be replaced in the furnace assembly


22


. Once the mold


34


has been positioned on the chill plate


36


with the lower end portion


48


of the mold extending through the opening


64




d


in the baffle


52




d


, the cover


30


can be placed on the furnace assembly


22


.




After the heating chamber


44


and mold


34


have been heated to a desired temperature, molten metal is poured through the funnel


32


into the mold


34


. The chill plate


36


is then lowered to initiate withdrawal of the mold


34


from the furnace assembly


22


.




As the chill plate


36


is lowered and the mold


34


is withdrawn from the furnace assembly


22


, the upper end portion


50


of the mold moves into engagement with the inner section


62




d


adjacent to the periphery of the opening


64




d


and the connector members or rods


134


and


136


. The force applied against the inner section


62




d


of the baffle


52




d


by the upper end portion


50


of the mold


34


is effective to break the connector members or rods


134


and


136


with a snapping action. Breaking the connector members or rods


134


and


136


releases the inner section


62




d


for movement out of the circular opening


130


in the outer section


60




d


. As this occurs, the inner section


62




d


of the baffle


52


falls downward onto the chill plate. The upper end portion


50


of the mold


34


can then move through the relatively large circular opening


130


in the stationary outer section


60




d


as the mold


34


continues to withdrawn from the furnace assembly.




The connector members or rods


134


and


136


are formed of a ceramic material such as quartz. However, the connector members or rods


134


and


136


could be formed of a different material if desired.




In the embodiment of the invention illustrated in

FIG. 9

, the connector members or rods


134


and


136


are separate from the outer section


60




d


and inner section


62




d


of the baffle


52




d


. However, if desired, the connector members or rods


134


and


136


could be connected with the lower side of the baffle


52




d


. The connector members or rods


134


and


136


may be connected with the lower side of the baffle


52




d


by a suitable adhesive or by mechanical fasteners.




Although the connector members or rods


134


and


136


are disposed beneath the baffle, the connector members or rods could be disposed above the baffle. If this was done, the connector members or rods


134


and


136


would be connected with the upper side of the inner section


62




d


of the baffle


52




d


by a suitable adhesive or mechanical fasteners.




If desired, the connector members or rods


134


and


136


may be embedded in the material forming the outer section


60




d


and inner section


62




d


of the baffle


52




d


. This would result in the connector members or rods


134


and


136


being enclosed by the material of the baffle.




Rather than having the connector members or rods


134


and


136


extend between spaced apart locations on the outer section


60




d


of the baffle


52




d


, the connector members or rods


134


and


136


could be shorter and extend only from the outer section


60




d


to the inner section


62




d


of the baffle


52




d


. Thus, a circular array of three or more relatively short connector members or rods may extend radially inward from the outer section


60




d


to the inner section


52




d


without spanning the opening


130


. If this was done, the relatively short connector members or rods may be attached to the lower sides of the outer section


60




d


and inner section


62




d


. Alternatively, the relatively short connector members or rods may be embedded in the material of the outer section


60




d


and inner section


62




d.






The outer section


60




d


of the baffle


52




d


consists of a single layer of graphite felt. Similarly, the inner section


62




d


consists of a single layer of graphite felt. However, the outer and inner sections


60




d


and


62




d


of the baffle


52




d


may have a different construction. For example, the outer and inner sections


60




d


and


62




d


may have the multilayered construction previously described in conjunction with FIG.


5


.




Baffle With Raised Inner Section




In the embodiments of the invention illustrated in

FIGS. 1-9

, the baffles


52


have been constructed with upper and lower major side surfaces of the outer sections


60


and inner sections


62


in a coplanar relationship. In the embodiment of the invention illustrated in

FIGS. 10 and 11

, the inner section of the baffle is disposed above and is supported by the outer section of the baffle. Since the embodiment of the invention illustrated in

FIGS. 10 and 11

is generally similar to the embodiments of the invention illustrated in

FIGS. 1-9

, similar numerals will be utilized to designate similar components, the suffix letter “e” being associated with the numerals of

FIGS. 10 and 11

to avoid confusion.




A baffle


52




e


is illustrated in

FIG. 10

in a furnace assembly


22




e


. The furnace assembly


22




e


has the same construction as the furnace assembly


22


of

FIG. 1. A

mold


34




e


extends through an opening


64




e


in a circular inner section


62




e


of the baffle


52




e


. The mold


34




e


is supported on a circular chill plate


36




e.






In accordance with one of the features of the embodiment of the invention illustrated in

FIGS. 10 and 11

, the inner section


62




e


of the baffle


52




e


is disposed above and is supported by an annular outer section


60




e


of the baffle


52




e


. When the mold


34




e


is to be withdrawn from the heating chamber


44




e


in the furnace assembly


22




e


in the manner previously explained in conjunction with the embodiment of the invention illustrated in

FIG. 1

, an upper end portion of the mold moves downward into engagement with the inner section


62




e


of the baffle


52




e


. Force applied against the inner section


62




e


of the baffle


52




e


by the upper end portion of the mold is effective to deflect an annular inner rim


160


(

FIG. 11

) of the outer section


60




e


. As this occurs, the baffle


52




e


moves into and through a circular opening


130




e


formed in the outer section


60




e


of the baffle


52




e.






The inner section


62




e


of the baffle


52




e


is then free to fall downward onto the chill plate


36




e


. The relatively large upper end portion of the mold


34




e


may then move through the relatively large circular opening


130




e


formed in the outer section


60




e.






The circular inner section


62




e


may be placed on the upper major side surface of the outer section


60




e


without being connected to the outer section


60




e


. This would enable the lower major side surface of the inner section


62




e


to slide on the upper major side surface of the outer section


60




e.






Alternatively, the inner section


62




e


of the baffle


52




e


may be secured to the outer section


60




e


of the baffle. This may be done with adhesive or with mechanical fasteners. Assuming that adhesive is utilized to connect the inner section


62




e


of the baffle


52




e


with the upper side of the outer section


60




e


, spaced apart bodies of adhesive may be placed on either the annular inner rim portion


160


(

FIG. 11

) of the outer section


60




e


on an annular rim portion


164


of the inner section


62




d


. Rather than using spaced apart bodies of adhesive, a single annular body of adhesive may be positioned on either the rim portion


160


of the outer section


60




e


or the rim portion


164


of the inner section


62




e


of the baffle


52




e.






It is contemplated that it may be desired to install the baffle


52




e


in the furnace


22




e


by first positioning the outer section


60




e


of the baffle in the furnace assembly and then moving the inner section


62




e


through the opening


130




e


in the outer section


60




e


of the baffle. If this is to be done, notches or slots may be formed in the rim portion


160


of the outer-section


60




e


of the baffle


52




e


. The inner section


62




e


of the baffle would then be oriented with its major side surfaces extending perpendicular to the major side surfaces of the outer section


60




e


of the baffle and aligned with the notches in the rim portion


160


of the outer section


60




e


of the baffle. This would allow the inner section


62




e


of the baffle to be moved upward through the opening


130


and then moved to the orientation illustrated in

FIGS. 10 and 11

.




The outer section


60




e


and inner section


62




e


of the baffle


52




e


may be cut from a single piece of material. If this is done, the cut may be formed as a portion of a cone having a central axis coincident with the centers of the outer section


60




e


and inner section


62




e


of the baffle


52




e


. This results in the opening


130




e


in the outer section


60




e


of the baffle


52




e


having an axially downward and radially outward (as viewed in

FIG. 11

) sloping side surface. The rim portion


164


of the inner section


62




e


of the baffle


52




e


would have a radially inward and upward (as viewed in

FIG. 11

) slopping side surface which corresponds to the sloping side surface of the opening


130




e.






Although the outer section


60




e


and inner section


62




e


may be formed of many different materials, they are formed of graphite felt. If desired, the outer section


60




e


and inner section


62




e


of the baffle


52




e


may have a layered construction, similar to the layered construction of FIG.


5


.




In the embodiment illustrated in

FIGS. 10 and 11

, the inner section


62




e


of the baffle


52




e


is disposed above the outer section


60




e


of the baffle. However, if desired, the inner section


62




e


may be supported in the opening


130




e


in the outer section


60




e


baffle


52




e


. To support the inner section


62




e


of the baffle


52




e


in the opening


130




e


, the circular inner section


62




e


may be provided with radially outward projecting tabs which extend over and engage radially inward projecting tabs on the outer section


60




e.






Latches




In the embodiment of the invention illustrated in

FIGS. 1-11

, the baffle


52


is supported by a base portion


86


(

FIG. 1

) of the furnace assembly


22


. In the embodiments of the invention of the illustrated in

FIGS. 12-14

, the baffle is supported by latches connected with the furnace assembly. Since the embodiments of the invention illustrated in

FIGS. 12-14

are generally similar to the embodiments of the invention illustrated in

FIGS. 1-11

, similar numerals will be utilized to designate similar components, the suffix letter “f” being associated with the embodiments of

FIGS. 12 and 13

.




A baffle


52




f


is disposed at a lower end portion of a furnace assembly


22




f


. A mold


34




f


has a lower end portion


48




f


which extends through an opening


64




f


formed in the baffle


52




f


into engagement with a circular chill plate


36




f


. The furnace assembly


22




f


has the same general construction as the furnace


22


of FIG.


1


. The baffle


52




f


may have the same construction as any one of the baffles illustrated in

FIGS. 1-11

.




In accordance with one of the features of the embodiment of the invention illustrated in

FIGS. 12 and 13

, a plurality of latches


170


are arranged in a circular array at the lower end portion of the furnace assembly


22




f


. Although only two latches have been illustrated schematically in

FIG. 12

, it should be understood that additional latches may be provided if desired. In order to provide a stable support for the baffle


52




f


, it is believed that it may be desired to have three or more latches disposed adjacent to the lower end portion of the furnace assembly


22




f.






When the mold


34




f


is to be positioned in the furnace assembly, the chill plate


36




f


may be lowered. The baffle


52




f


is then be placed on the upper side surface of the chill plate. The mold


34




f


may be positioned on the chill plate


36




f


with the lower end portion


48




f


of the mold extending through the opening


164




f


in the baffle


52




f.






Once the baffle


52




f


and mold


34




f


have been positioned on the chill plate


36




f


, the chill plate is raised to move the mold into the heating chamber


44




f


of the furnace assembly


22




f


. As the chill plate


34




f


is raised, a circular outer rim portion


82




f


of the baffle


52




f


engages the latches


170


. Upward force applied by the rim portion


82




f


of the baffle


52




f


is effective to operate the latches


170


to a retracted condition so that the baffle


52




f


can be moved upward past the latches


170


. Once the outer rim portion


82




f


of the baffle


52




f


has moved upward past the latches


170


, the latches operate to the illustrated extended condition. When the latches


170


are in a extended condition, they extend beneath the outer rim portion


82




f


of the baffle


52




f


to enable the latches to support the baffle.




When the mold


34




f


is to be withdrawn from the heating chamber


44




f


, the chill plate


36




f


is lowered in the manner previously explained. As the mold moves downward, force applied against the baffle


52




f


by relatively large upper end portion of the mold releases connectors which interconnect outer and inner sections


60


and


62


of the baffle in the manner previously explained in conjunction with the embodiments of the invention illustrated in

FIGS. 1-11

. This enables the inner section of the baffle


52




f


to fall downward onto the chill plate


36




f


. The upper portion of the mold


34




f


can then move through the resulting relatively large opening in the baffle


52




f.






The latches


170


may be manually actuated to a retracted condition to release the outer section of the baffle


52




f


after the mold has been withdrawn from the furnace assembly


22




f


. The latches


170


may be manually actuated to the retracted condition by pulling on rods connected with the latches. Alternatively, the latches


170


may be actuated to the retracted condition by operating hydraulic or pneumatic motors connected with the latches.




It is contemplated that the latches


170


may have many different constructions. This specific latches


170


illustrated schematically in

FIG. 12

have the construction illustrated in FIG.


13


. The latch


170


includes a latch member


172


which is biased toward the extended condition illustrated in

FIG. 13

by a spring


174


. The latch member


172


is enclosed within a housing


176


. Suitable stops extend from the housing


176


into engagement with latch member


172


to limit movement of the latch member. Alternatively, the latch member


172


may be provided with a projection which engages a slot in the housing


176


to limit movement of the latch member


172


under the influence of the spring


174


.




When the baffle


52




f


and chill plate


36




f


are raised to move the mold


34




f


into the furnace assembly


22




f


in the manner previously described, the annular outer rim portion


82




f


of the baffle


52




f


moves into engagement with a cam surface


180


on the latch member


172


. Force applied against the cam surface


180


by the annular outer rim portion


82




f


of the baffle


52




f


forces the latch member into the housing


176


against the influence of the spring


174


. As the chill plate


36




f


and baffle


52




f


continue to be raised, the baffle moves above the latch member


172


. As this occurs, the spring


174


moves the latch member from a retracted condition to the extended condition illustrated in FIG.


13


.




When the chill plate


36




f


begins to move downward to withdraw the mold


34




f


from the heating chamber


44




f


, the baffle


52




f


is held against movement relative to the furnace assembly


22




f


by engagement of a lower side of the baffle with a support surface


184


on the latch member


172


. This results in the baffle


52




f


being supported by the latches


170


during withdrawal of the lower portion


48




f


of the mold


34




f


from the heating chamber


44




f.






When the upper end portion


50




f


of the mold


34




f


engages the baffle


52




f


, force is transmitted from the upper end portion of the mold


34




f


through the inner section and outer section of the baffle


52




f


to the latches


170


. This enables the upper end portion of the mold to apply force against the baffle


52




f


to release the connectors in the manner previously explained herein. Releasing the connectors allows the inner section of the baffle to fall downward onto the chill plate


36




f


. The outer section of the baffle


52




f


is held in a position adjacent to the lower end portion of the heating chamber


44




f


by the latches


170


.




In the embodiment of the invention illustrated in

FIGS. 12 and 13

, the latches


170


have spring biased latch members


172


. In the embodiment of the invention illustrated in

FIG. 14

, the latches are gravity biased. Since the embodiment of the invention illustrated in

FIG. 14

is generally similar to the embodiment of the invention illustrated in

FIGS. 12 and 13

, similar numerals will be utilized to identify similar components, the suffix “g” being associated with the numerals of FIG.


14


.




A plurality of latches


170




g


are mounted adjacent to the lower end portion of the furnace assembly


22




f


in the manner illustrated schematically for the latches


170


in FIG.


12


. The latch


170




g


includes a latch member


172




g


which is pivotally supported at


190


for movement between an extended condition illustrated in solid lines in

FIG. 14 and a

retracted condition in dashed lines in FIG.


14


. When the latch member


172




g


is in the extended condition illustrated in solid lines in

FIG. 14

, a relatively heavy nose end portion


194


of the latch member


172




g


is urged downward by the effect of gravity to position a stop surface area


196


on the latch member


172




g


in engagement with a stopped member


198


.




When a mold, corresponding to the mold


34




f


of

FIG. 12

is to be moved into a furnace assembly corresponding to the furnace assembly


22




f


, a baffle having any one of the constructions illustrated in

FIGS. 1-11

is positioned on a chill plate. The baffle and mold are then raised to move the mold into a heating chamber of the furnace assembly in the manner previously explained in conjunction with the embodiment of the invention illustrated in FIG.


12


.




As the chill


36




f


plate and baffle


52




f


(

FIG. 12

) move upward toward the heating chamber of the furnace assembly, an annular outer rim portion


82




f


(

FIG. 12

) of the baffle moves into engagement with a cam surface


180




g


(

FIG. 14

) on the nose end portion


194


of the latch member


172




g


. The force applied against the cam surface


180




g


(

FIG. 14

) pivots the latch member


172




g


in a counter clockwise direction (as viewed in

FIG. 14

) about the pivot connection


190


. A stop member


200


is provided to limit pivotal movement of the latch member


172




g


about the pivot connection


190


.




As the chill plate


36




f


(

FIG. 12

) and baffle


52




f


continue to move upward, the circular outer rim portion


82




f


of the baffle moves above the nose end portion


194


(

FIG. 14

) of the latch member


172




g


. This releases the latch member


172




g


for clockwise pivotal movement from the orientation illustrated in dash lines in

FIG. 14

to the orientation illustrated in solid lines in FIG.


14


. As this occurs, a support surface


184




g


moves beneath the lower surface of the baffle.




When the chill plate


36




f


(

FIG. 12

) is subsequently lowered to withdraw the mold


34




f


from the furnace assembly


22


, the baffle


52




f


moves downward onto the support surface


184




g


(

FIG. 14

) on the latch member


172




g


. The support surface


184




g


is skewed at an acute angle to the path of movement of the chill, plate


36




f


(FIG.


12


). Therefore, the support surface


184




g


tends to center the baffle


52




f


relative to the path of movement of the chill plate


36




f


. As the chill plate


36




f


continues to be lowered, the upper end portion of the mold


34




f


engages the inner section of the baffle


52




f


and releases the connectors. As this is done, the outer section of the baffle is held stationary relative to the furnace assembly


22




f


by engagement with the support surfaces


184




g


on the latch members


172




g.






Conclusion




In view of the foregoing description, it is apparent that the present invention provides a new and improved apparatus and method for use in casting a metal article. The apparatus may include a furnace assembly


22


having a heating chamber


44


. A chill plate


36


may be provided to move a mold


34


into and out of the heating chamber


44


. A baffle


52


may be utilized at a lower end portion of the heating chamber


44


to at least partially block heat flow from the heating chamber during withdrawal of the mold


34


from the heating chamber.




The baffle


52


may have an inner section


62


with an opening


64


through which the mold


34


extends when the mold is in the heating chamber


44


. An outer section


60


of the baffle


52


may extend around the inner section


62


of the baffle. A plurality of connectors


70


may extend between the outer and inner sections


60


and


62


of the baffle


52


and hold them against movement relative to each other. The connectors


70


may be releasable to enable the inner section


62


of the baffle


52


to move downward relative to an outer section


60


of the baffle


52


to increase the size of an opening through which the mold, moves from the heating chamber


44


.




The connectors


70


may extend between the outer and inner sections


60


and


62


of the baffle


52


and retain one or more side surfaces


76


,


78


,


92


and/or


94


on the outer and inner sections


60


and


62


of the baffle in a coplanar relationship when the mold


34


is in the heating chamber


44


of the furnace assembly


22


. The connectors


70


may be releasable under the influence of force transmitted from the mold


34


to enable the inner section


62


of the baffle to move downward relative to the outer section


60


of the baffle


52


.




The baffle


52


may be formed as one-piece (

FIGS. 2-5

) with the connectors


70


integrally formed as one-piece with the outer and inner sections


60


and


62


of the baffle


52


. The connectors


70


may be broken under the influence of force transmitted from the mold


34


to the baffle


52


during lowering of the mold from the heating chamber


44


. If desired, the outer and inner sections


60


and


62


of the baffle


52


may be separated by a plurality of slits


74


with the connectors


70


disposed between end portions of the slits


74


and formed of the same material which forms the outer and inner sections


60


and


62


of the baffle.




The outer and inner sections


60


and


62


of the baffle


52


may be formed as separate pieces (FIGS.


6


-


11


). If this is done, the inner section


62


of the baffle may initially be disposed in an opening


130


in the outer section


60


of the baffle and held in its initial position by a plurality of connectors (


70




a


,


70




b


,


70




c


or


70




d


) which extend between the outer and inner sections of the baffle. The connectors (


70




a


,


70




b


,


70




c


or


70




d


) are releasable to enable the inner section (


62




a


,


62




b


,


62




c


or


62




d


) of the baffle to move downward out of the opening


130


in the outer section of the baffle as the mold


34


is moved from the heating chamber


44


of the furnace assembly


22


.




The inner section


52




e


(

FIGS. 10 and 11

) of the baffle may be disposed above and at least partially supported by the outer section


60




e


of the baffle


52




e


. If this is done, the inner section


62




e


of the baffle may be moved downward through an opening


130




e


in the outer section


60




e


of a baffle to increase the size of an opening through which the mold


34




e


is moved from the heating chamber.




Although the baffle


52


may be connected with a furnace assembly


22


in many different ways, it is believed that it may be desired to utilize latches


170


(

FIGS. 12-14

) to connect the baffle with the furnace assembly. The outer section


60


of the baffle


52


may be moved into engagement with and move the latches


170


during movement of the baffle into the heating chamber


44


in the furnace assembly


22


. The latches


280


are effective to retain the outer section


60


of the baffle


52


against downward movement relative to the furnace assembly during movement of the mold


34


out of the heating chamber


44


in the furnace assembly


22


.




The present invention has a plurality of different features which may be used together or separately. One or more of the features of the present invention may be utilized in association with one or more features of the prior art.



Claims
  • 1. An apparatus for use in casting a metal article, said apparatus comprising a furnace assembly having a heating chamber, a chill plate which is movable between raised and lowered positions and supports a mold in the heating chamber of said furnace assembly when said chill plate is in the raised position, a baffle, said baffle having an outer section which is connected with said furnace assembly and extends around an inner section of said baffle, said inner section of said baffle having an opening through which the mold extends when the mold is in the heating chamber of the furnace assembly, and a plurality of connectors which extend between said outer and inner sections of said baffle and hold said outer and inner sections of said baffle against movement relative to each other with upper side surfaces of said outer and inner sections of said baffle in a coplanar relationship when the mold is in the heating chamber of the furnace assembly, said plurality of connectors being releasable under the influence of force transmitted from the mold to enable said inner section of said baffle to move downward relative to the outer section of said baffle as the mold is lowered from the heating chamber, said side surface of said inner section of said baffle moving out of a coplanar relationship with said side surface of said outer section of said baffle as said inner section of said baffle moves downward relative to said outer section of said baffle.
  • 2. An apparatus as set forth in claim 1 wherein said plurality of connectors are integrally formed as one-piece with said first and second sections of said baffle and are effective to hold said inner section of said baffle against movement relative to said outer section of said baffle.
  • 3. An apparatus as set forth in claim 1 wherein said plurality of connectors include a plurality of staples, each of said staples having a first leg section which engages said outer section of said baffle, a second leg section which engages said inner section of said baffle, and a connector section which extends between said first and second leg sections and extends along said side surfaces of said outer and inner sections of said baffle when said side surfaces of said outer and inner sections of said baffle are in the coplanar relationship.
  • 4. An apparatus as set forth in claim 1 wherein said plurality of connectors include at least one body of adhesive which engages said inner and outer sections of said baffle and transmits force which retains said outer and inner sections of said baffle against relative movement.
  • 5. An apparatus as set forth in claim 4 wherein said at least one body of adhesive is at feast partially disposed in an opening in said outer section of said baffle.
  • 6. An apparatus as set forth in claim 4 wherein said at least one body of adhesive is at least partially disposed in engagement with side surfaces of said outer and inner sections of said baffle.
  • 7. An apparatus as set forth in claim 4 wherein said at least one body of adhesive is at least partially disposed in engagement with the side surfaces of said outer and inner sections of said baffle which are disposed in a coplanar relationship.
  • 8. An apparatus as set forth in claim 1 wherein said inner and outer sections of said baffle are separated by a plurality of slits, said plurality of connectors being at least partially disposed between end portions of slits of said plurality of slits.
  • 9. An apparatus as set forth in claim 1 wherein said baffle includes first and second layers of material, said connectors include at least a portion of at least one of said layers of material.
  • 10. An apparatus as set forth in claim 1 wherein said connectors are at least partially formed by material which extends between said outer and inner sections of said baffle, said connectors being breakable under the influence of force transmitted from the mold to said inner section of said baffle to release said inner section of said baffle for movement relative to said outer section of said baffle.
  • 11. An apparatus as set forth in claim 1 wherein an opening in said outer section of said baffle is only partially formed prior to transmission of force from the mold to said inner section of said baffle and release of said connectors, material of said baffle being torn upon release of said connectors to complete formation of the opening in said outer section of said baffle.
  • 12. An apparatus as set forth in claim 1 wherein said plurality of connectors are at least partially formed by a plurality of breakable rods which extend between said outer and inner sections of said baffle, said rods being breakable under the influence of force transmitted from the mold.
  • 13. An apparatus as set forth in claim 1 wherein said connectors include a plurality of members which extend between said outer and inner sections of said baffle, said plurality of members having central axes which extend generally parallel to the coplanar side surfaces of said outer and inner sections of said baffle.
  • 14. An apparatus as set forth in claim 13 wherein the plurality of members include staples having sections with central axes which extend generally parallel to the coplanar side surfaces of said outer and inner sections of said baffle.
  • 15. An apparatus as set forth in claim 13 wherein said plurality of members are breakable under the influence of force transmitted from the mold.
  • 16. An apparatus as set forth in claim 13 wherein said plurality of members are disposed in engagement with said outer and inner sections of said baffle when said side surfaces of said outer and inner sections of said baffle are in a coplanar relationship, said plurality of members being disengaged from at least one of said outer and inner sections of said baffle during movement of the mold from the raised position to the lowered position.
  • 17. An apparatus as set forth in claim 1 further including a plurality of latches connected with said furnace assembly and engagable with said outer section of said baffle to retain said outer section of said baffle against downward movement relative to the said furnace assembly during downward movement of said chill plate toward the lowered position.
  • 18. An apparatus for use in casting a metal article in a mold, said apparatus comprising a furnace assembly having a heating chamber, a chill plate which is movable between raised and lowered positions and which supports the mold in the heating chamber of said furnace assembly when said chill plate is in the raised position, and a one-piece baffle which is connected with said furnace assembly and which includes first and second sections interconnected by a plurality of connector sections which are integrally formed as one-piece with said first and second sections of said baffle, said connector sections of said baffle being breakable under the force transmitted from the mold to said baffle during lowering of said chill plate to move the mold from the heating chamber.
  • 19. An apparatus as set forth in claim 18 wherein said first and second sections of said baffle are separated by a plurality of slits formed in said baffle, said connector sections being disposed between end portions of slits of said plurality of slits.
  • 20. An apparatus as set forth in claim 18 wherein said baffle includes first and second layers of material, said first and second sections of said baffle being separated by a plurality of sets which extend through said first and second layers of material, said first layer of material being severed at said connector sections of said baffle, said second layer of material extends from said first section of said baffle to said second section of said baffle at said connector sections of said baffle.
  • 21. An apparatus as set forth in claim 18 wherein said first section of said baffle has an annular configuration and circumscibes said second section of said baffle, said first section of said baffle having a circular outer rim portion which is connected with said furnace assembly, said second section of said baffle having a circular rim portion which is connected with a circular inner rim portion of said first section of said baffle by said connector sections.
  • 22. An apparatus as set forth in claim 21 wherein said second section of said baffle includes a opening through which the mold extends when the mold is in the heating chamber of the furnace assembly.
  • 23. An apparatus as set forth in claim 18 further including a plurality of latches which engage said first section of said baffle to block downward movement of said first section of said baffle during breaking of said connector sections of said baffle.
  • 24. An apparatus as set forth in claim 18 wherein said first and second sections of said baffle have side surfaces which are disposed in a coplanar relationship.
  • 25. An apparatus as set forth in claim 18 further including a plurality of latches connected with said furnace assembly and engagable with said first section of said baffle during upward movement of said chill plate, said latches being effective to retain said first section of said baffle against downward movement relative to said furnace assembly during downward movement of said chill plate toward the lowered position.
  • 26. An apparatus for use in casting a metal article in a mold, said apparatus comprising a furnace assembly having a heating chamber, a chill plate which is movable between raised and lowered positions and which supports the mold in the heating chamber of said furnace assembly when said chill plate is in the raised position, a baffle, said baffle having an outer section which is connected with said furnace assembly and an inner section which is disposed within an opening in said outer section of said baffle with upper side surfaces of said outer section and inner section in a coplanar relationship, said inner section of said baffle having an opening through which the mold extends when said chill plate is in the raised position, and a plurality of connector members which extend between said outer and inner sections of said baffle and transmit force to maintain said inner section of said baffle in said opening in said outer section of said baffle, said connector members being releasable under the influence of force transmitted from the mold to said inner section of said baffle to enable said inner section of said baffle to move downward out of the opening in said outer section of said baffle as said chill plate and the mold are lowered from the raised position toward the lowered position.
  • 27. An apparatus as set forth in claim 26 wherein said connector members are breakable under the influence of force transmitted from the mold to said inner section of said baffle.
  • 28. An apparatus as set forth in claim 26 wherein each connector member of said plurality of connector members includes first and second end portions which are interconnected by an intermediate portion, said first end portion of each connector member of said plurality of connector members being disposed in engagement with said outer section of said baffle, said second end portion of each connector member of said plurality of connector members being disposed in engagement with said inner section of said baffle, said intermediate portion of each connector member of said plurality of connector members extends along side surfaces of said outer and inner sections of said baffle when said inner section of said baffle is in said opening in said outer section of said baffle.
  • 29. An apparatus as set forth in claim 28 wherein said first and second end portions of each connector member extend transverse to said central portion of each connector member.
  • 30. An apparatus as set forth in claim 26 wherein each connector member of said plurality of connector members has first and second end portions which engage said outer section of said baffle and an intermediate portion which is disposed between said first and second end portions and engages said inner section of said baffle.
  • 31. An apparatus as set forth in claim 30 wherein said connector members are breakable under the influence of force transmitted from the mold to said inner section of said baffle to release said connector members and enable said inner section of said baffle to move downward out of the opening in said outer section of said baffle.
  • 32. An apparatus as set forth in claim 30 wherein each of said connector members is formed by a rod of ceramic material.
  • 33. An apparatus as set forth in claim 26 wherein at least some of said connector members extend between said baffle and said furnace assembly to support said baffle in said furnace assembly.
  • 34. An apparatus set forth in claim 26 further including a plurality of latches connected with said furnace assembly and engageable with said outer section of said baffle to retain outer section of said baffle against downward movement relative to said furnace assembly during at least a portion of the downward movement of said chill plate toward the lowered position.
  • 35. An apparatus as set forth in claim 26 wherein said outer and inner sections of said baffle have side surfaces which are in a coplanar relationship when the inner section of said baffle is in said opening in said outer section of said baffle.
  • 36. An apparatus as set forth in claim 26 wherein plurality of connector members include adhesive which engages said outer and inner sections of said baffle and transmits force which retains said outer and inner sections of said baffle against relative movement.
  • 37. An apparatus as set forth in claim 26 wherein said plurality of connector members include a plurality of bodies of adhesive which are at least partially disposed in the opening in said outer section of said baffle and are effective to transmit force which retains said inner section of said baffle in the opening in said outer section of said baffle.
  • 38. An apparatus as set forth in claim 26 wherein said plurality of connector members include a plurality of bodies of adhesive which are at least partially disposed in engagement with side surfaces of said outer and inner sections of said baffle.
  • 39. An apparatus set forth in claim 26 wherein said plurality of connector members include a plurality of bodies of adhesive which are at least partially disposed in engagement with side surfaces of said outer and inner sections of said baffle which are disposed in a coplanar relationship.
  • 40. An apparatus for use in casting a metal article, said apparatus comprising a furnace assembly having a heating chamber, a chill plate which is movable between raised and lowered positions and supports the mold in the heating chamber of said furnace assembly when said chill plate is in the raised position, a baffle, said baffle having an outer section which is connected with said furnace assembly and extends around an inner section of said baffle, said inner section of said baffle having an opening through which the mold extends when the mold is in the heating chamber of the furnace assembly, and a plurality of connectors which extend between said outer and inner sections of said baffle and hold said outer section of said baffle against movement relative to said inner section of said baffle, said baffle is formed of one piece of material which extends from said outer section of said baffle through said plurality of connectors to said inner section of said baffle, said plurality of connectors being releasable under the influence of force transmitted from the mold to enable said inner section of said baffle to move downward relative to the outer section of said baffle as the mold is lowered from the heating chamber.
  • 41. An apparatus as set forth in claim 40 wherein said plurality of connectors retain side surfaces of said outer and inner sections of said baffle in a coplanar relationship with side surfaces of said connectors.
  • 42. An apparatus as set forth in claim 40 wherein said outer and inner sections of said baffle are formed by a plurality of layers which include said one piece of material.
  • 43. An apparatus for use in casting a metal article, said apparatus comprising a furnace assembly having a heating chamber, a chill plate which is movable between raised and lowered positions and supports the mold in the heating chamber of said furnace assembly when said chill plate is in the raised position, a baffle, said baffle having an outer section which is connected with said furnace assembly and extends around an inner section of said baffle, said inner section of said baffle having an opening through which the mold extends when the mold is in the heating chamber of the furnace assembly, and a plurality of connectors which extend between said outer and inner sections of said baffle and hold said outer and inner sections of said baffle against movement relative to each other, said baffle consists of one piece of material which extends from said outer section of said baffle through said plurality of connectors to said inner section of said baffle, said plurality of connectors being releasable under the influence of force transmitted from the mold to enable said inner section of said baffle to move downward relative to the outer section of said baffle as the mold is lowered from the heating chamber.
  • 44. An apparatus for use in casting a metal article, said apparatus comprising a furnace assembly having a heating chamber, a chill plate which is movable between raised and lowered positions and supports a mold in the heating chamber of said furnace assembly when said chill plate is in the raised position, a baffle, said baffle having outer and inner sections, and a plurality of connectors which extend between said outer and inner sections of said baffle and hold said outer and inner sections of said baffle against movement relative to each other, said plurality of connectors being integrally formed as one piece with said outer and inner sections of said baffle, said plurality of connectors being releasable under the influence of force transmitted from the mold to enable said inner section of said baffle to move downward relative to the outer section of said baffle as the mold is lowered from the heating chamber.
  • 45. An apparatus as set forth in claim 44 wherein said outer and inner sections of said baffle are separated by a plurality of slits, said plurality of connectors being at least partially disposed between end portions of silts of said plurality of slits.
  • 46. An apparatus as set forth in claim 44 wherein said baffle includes first and second layers of material, said connectors include at least a portion of at least one of said layers of material.
  • 47. A method of casting a metal article, said method comprising the steps of connecting a baffle with a furnace assembly, retaining upper side surfaces of outer and inner sections of the baffle in a coplanar relationship with each other, said step of retaining side surfaces of outer and inner of the baffle in said coplanar relationship includes transmitting force through a plurality of connectors which extend between the outer and inner sections of the baffle, withdrawing a mold from the furnace assembly, releasing the plurality of connectors under the influence of force applied against the baffle by the mold as the mold is withdrawn from the furnace assembly, and moving the inner section of the baffle relative to the outer section of the baffle as the mold continues to be withdrawn from the furnace assembly after releasing the plurality of connectors.
  • 48. A method as set forth in claim 47 further including the step of supporting the mold on a chill plate with the mold extending through the baffle into the furnace assembly while the baffle is connected with the furnace assembly and while the side surfaces of the outer and inner sections of the baffle are in the coplanar relationship, said step of withdrawing the mold from the furnace assembly includes moving the chill plate and mold downward away from the furnace assembly.
  • 49. A method as set forth in claim 47 wherein the connectors are integrally formed as one piece with the outer and inner sections of the baffle, said step of releasing the plurality of connectors includes releasing the plurality of connectors with a tearing action.
  • 50. A method as set forth in claim 47 wherein the connectors are integrally formed as one piece with the outer and inner sections of the baffle, said step of releasing the plurality of connectors includes releasing the plurality of connectors with a snapping action.
  • 51. A method as set forth in claim 47 wherein each connector of the plurality of connectors includes a staple having a first leg section which engages the outer section of the baffle and a second leg section which engages the inner section of the baffle, said step of releasing the plurality of connectors includes disconnecting at least one of the leg sections of each of the staples from a section of the baffle.
  • 52. A method as set forth in claim 47 wherein each connector of the plurality of connectors includes at least one body of adhesive which engages the inner and outer sections of the baffle, said step of releasing the plurality of connectors includes disconnecting the bodies of adhesive from a section of the baffle.
  • 53. A method as set forth in claim 47 wherein the connectors are at least partially formed by material which extends between the outer and inner sections of the baffle, said step of releasing the plurality of connectors includes breaking the plurality of connectors.
  • 54. A method as set forth in claim 47 wherein the plurality of connectors include a plurality of rods which extend between the outer and inner sections of the baffle, said step of releasing the plurality of connectors includes breaking the plurality of rods.
  • 55. A method as set forth in claim 47 wherein said step of connecting the baffle with the furnace assembly includes engaging the outer section of the baffle with a plurality of latches, said step of moving the inner section of the baffle relative to the outer section of the baffle is at least partially performed while engaging the outer section of the baffle with the plurality of latches.
US Referenced Citations (11)
Number Name Date Kind
3714977 Terkelsen Feb 1973 A
3810504 Piwonka May 1974 A
4108236 Salkeld Aug 1978 A
4757856 George Jul 1988 A
4763716 Graham et al. Aug 1988 A
4773467 Graham et al. Sep 1988 A
4774992 George Oct 1988 A
4969501 Brokloff et al. Nov 1990 A
5429176 Atkinson et al. Jul 1995 A
5778961 Hugo et al. Jul 1998 A
6276432 Thompson et al. Aug 2001 B1