Method for attaching a jaw to a vise-like workholding apparatus

Information

  • Patent Grant
  • 6170814
  • Patent Number
    6,170,814
  • Date Filed
    Tuesday, March 17, 1998
    27 years ago
  • Date Issued
    Tuesday, January 9, 2001
    24 years ago
Abstract
A method for attaching a jaw to a vise-like workholding apparatus. The method includes placing the jaw member onto a support member of the workholding apparatus in a first direction that is perpendicular to a worksurface of the workholding apparatus. The jaw member is placed such that at least a portion of the support member is received within a cavity in the jaw member in a first released position. The method also includes applying a first axial force in a first axial direction to the jaw member to cause the jaw member to move axially in the first axial direction to a second position wherein it is retained on the support member.
Description




FEDERALLY SPONSORED RESEARCH




Not applicable.




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to workholding apparatuses and, more particularly, is directed to removable jaws for vise-like workholders.




2. Description of the Invention Background




During the machining of a “workpiece” on a machine tool apparatus such as a milling machine or the like, single or multiple workpieces are typically held in place by a precision vise or clamping member (“a vise-like workholder”) that is attached to the machine. Exemplary vise-like workholders that are adapted to hold a single workpiece are disclosed in U.S. Pat. No. 4,928,937 to Bernstein, U.S. Pat. No. 4,898,371 to Mills et al., U.S. Pat. No. 4,569,509 to Good, and U.S. Pat. No. 4,098,500 to Lenz.




As can be gleaned from review of those patents, such vise-like workholders are adapted to clamp a workpiece between opposing jaw members operably supported on a base. Typically, one jaw member is fixed and the other jaw member is movable relative to the fixed jaw member by means of a screw member housed within the base. As the movable jaw member is moved toward the fixed jaw member, the workpiece is clamped therebetween.




Another vise-like workholder is disclosed in U.S. Pat. No. 2,564,138 to Walker. This workholder includes jaw support members that each have a camming portion that is adapted to engage a corresponding undercut portion provided on a jaw member. The rear portion of each jaw member is also provided with a transverse slot that is adapted to receive a transverse bar formed in a corresponding jaw support member. A second transverse slot is provided in the front portion of each jaw member for receiving a corresponding spring strip that is attached to the forward portion of the jaw member. The spring strip serves to bias the jaw member in a slightly upward direction relative to the jaw support member. This jaw member arrangement, however, is less desirable because debris can accumulate in the exposed slot and become lodged between the jaw support member and the jaw member as the support member is advanced on the vise base.




Other vise-like workholders are capable of holding two or more workpieces in side-by-side orientations. Examples of such “two-station” workholders are disclosed in U.S. Pat. No. 5,098,073 to Lenz, U.S. Pat. No. 5,094,436 to Stephan, III, U.S. Pat. No. 5,022,636 to Swann, U.S. Pat. No. 4,934,674 to Bernstein, and U.S. Pat. No. 4,529,183 to Krason et al. Such workholders typically comprise a base that has a central jaw member fixed thereto. Two outer jaw members are operably supported on the base and can be selectively positioned relative to the fixed central jaw member by a vise screw that is operably received in a longitudinal cavity provided in the base.




The workpiece or workpieces are typically supported on the workholder bases of each of the above-mentioned workholders and are secured in position by at least two jaw members. Prior jaw member arrangements typically employed hardened steel jaw plates that were removably attached to a jaw member that was movably supported on the base. Steps were often machined in the jaw plates to accommodate workpieces of different heights. However, the number of different workpiece configurations that could be clamped utilizing such system were generally limited to shapes with at least one straight side.




One type of workholder equipped with a removable jaw member is disclosed in U.S. Pat. No. 463,332 to Giles. The removable jaw member employed by this workholding device has a socket formed therein with undercut portions adapted to receive a support member having beveled edges. To attach the jaw member to the support member, the beveled portion of the support member is aligned with the jaw member socket such that it can be inserted therein. Thereafter, the jaw member is rotated ninety degrees causing the beveled edges of the support member to engage the corresponding undercut portions of the jaw member socket. Because the socket occupies a large portion of the jaw member, this removable jaw member is ill-suited to have workpiece retaining grooves or cavities machined in its upper surface due to the relatively small amount of material provided between the top of the jaw member and the support member socket.




Another workholding device that employs a removable jaw member is disclosed in U.S. Pat. No. 2,880,638 to Muggli et al. This removable jaw member arrangement includes a jaw “nut” or support member that is adapted to support the removable jaw member on a vise base. The removable jaw member has a cavity formed therein that is adapted to receive a portion of the jaw nut that protrudes above the work surface of the vise base. The cavity and the jaw nut have corresponding sloping surfaces that are designed to receive a hardened semi-spherical insert positioned therebetween. The insert is retained in that position by an adjusting screw that extends through the rear portion of the jaw member to engage a flat surface on the rear of the jaw nut. This arrangement requires the use of hand tools to change the removable jaw member and the retaining screw is susceptible to being loosened during the machining process. In addition, there is not sufficient material between the upper surface of the jaw member and the cavity to accommodate grooves or retaining cavities in the top of the removable jaw member.




U.S. Pat. No. 4,928,937 to Bernstein also discloses a machine vise that has a fixed jaw member and a movable jaw member. The movable jaw member is removably attached to a movable support member in the manner taught in U.S. Pat. No. 2,880,638 to Muggli et al. However, the Bernstein patent teaches that the set screw can be replaced with a spring-biased detent that is designed to engage a cam surface on the movable support member to retain the jaw member on the support member. The detent also serves to urge the jaw member into sliding contact with the base. However, due to the relatively small amount of material between the upper surface of the jaw member and the cavity therein, such jaw member attachment arrangement is ill-suited for use in applications wherein it is desirable to machine workpiece retaining grooves or cavities in the upper surface of the jaw member. In addition, each jaw member must be fitted with a spring-loaded detent.




Another detachable jaw member arrangement for a vise-like workholding apparatus is disclosed in U.S. Pat. No. 5,024,427 to Swann. This device utilizes a removable pin arrangement for attaching a removable jaw member to a jaw nut. Such pin arrangement, however, requires the jaw nut to have a relatively high portion protruding into the jaw member rendering that portion of the jaw member unavailable to have workpiece retaining grooves, etc. machined therein.




Yet another workholding device with detachable jaw members is disclosed in U.S. Pat. No. 5,458,321 to Durfee, Jr. The device disclosed in this patent includes a movable jaw support member that is operably supported within a groove in a vise base. A portion of the support member protrudes from the groove in the base and has a transverse groove in one end thereof and a spring biased retaining pin which protrudes from the opposite end thereof along an axis that is perpendicular to the transverse groove. A cavity is provided in the removable jaw member that is sized to receive the movable jaw support member therein. Two transverse pins are provided in the jaw member and are each arranged to engage the transverse groove in the movable support member depending upon the orientation by which the jaw member is positioned on the support member. A shallow groove or undercut is also provided in the jaw member directly below each transverse pin. To attach the jaw member to the support member, the jaw member is placed over the support member such that one of the transverse pins engages the transverse groove therein. Thereafter, the jaw member is pivotally pressed onto the support member such that the spring biased retaining pin engages a corresponding undercut portion located in the jaw member. Thus, the jaw member is removably secured to the movable member by virtue of the engagement between one of the transverse pins and the transverse groove in the support member and the retaining pin's engagement with one of the undercut portions in the jaw member. This jaw member arrangement, however, is expensive to fabricate because each jaw member must be equipped with transverse pins. In addition, the transverse pins limit the amount of jaw member material that can be removed from the upper surface of the jaw member to accommodate various workpieces. Furthermore, the jaw cannot be installed or removed by vertical movement and, indeed, the user must utilize a prybar-like tool to remove the jaw from the support member. Thus, if such a tool is misplaced or lost, valuable machining time may be lost during changeover operations.




Accordingly, there is a need for a removable jaw member for a vise-like workholder that is economical to fabricate.




There is a further need for a removable jaw member having the above-mentioned attributes that can also accommodate cavities and grooves machined in its upper surface and clamping surfaces to enable the jaw member to clamp workpieces having irregular shapes.




There is yet another need for a detachable jaw for a vise-like apparatus that can be attached and removed from the apparatus without the use of additional tools.




There is still another need for a detachable jaw for a vise-like workholding apparatus that lends itself to automated attachment and detachment to the apparatus without the use of additional tools.




Another need exists for a vise-like workholding apparatus that includes removable jaws that can have grooves and cavities machined in their upper surface and that can be easily attached and detached from the apparatus.




SUMMARY OF THE INVENTION




In accordance with a particular preferred form of the present invention, there is provided a removable jaw assembly for use in connection with a vise-like workholder that has a base that defines a worksurface. The removable jaw assembly comprises a tower portion on the workholding apparatus that protrudes above the worksurface and has a longitudinal axis. The preferred assembly also includes a removable jaw member that has a cavity therein sized to receive the tower portion therein such that the jaw member may be selectively longitudinally moved on the tower portion between a released position and an attached position. The tower portion also preferably has at least one retainer therein that is adapted to engage an engagement area formed in a wall of the cavity at right angles to the longitudinal axis when the tower portion is received in the cavity. Preferably, the engagement area includes first and second cavities that correspond with each retainer such that when the jaw member is in the released position, the retainer engages a first cavity and when the jaw member is moved to the attached position, the retainer engages a second cavity that is sized and oriented to cooperate with the retainer to retain the jaw member on the tower portion and preferably bias the jaw member onto the worksurface. In addition, the tower portion preferably has an angled retaining surface that extends along an axis that is substantially transverse to the longitudinal axis and is adapted to cooperate with at least one groove provided in the jaw member to attach the jaw member to the tower portion in at least one clamping position. In another embodiment, two grooves are provided in the cavity to enable the jaw member to be attached to the tower portion in two clamping positions.




Thus, it is an object of the present invention to provide a relatively inexpensive removable jaw assembly that can be used in connection with a vise-like workholder.




It is another object of the present invention to provide a removable jaw assembly that can be easily attached and detached from the workholder by manual and automatic means, if desired.




Yet another object of the present invention is to provide a removable jaw assembly in which various workpiece-compatible cavities and grooves may be machined therein.




Accordingly, the present invention provides solutions to the problems discussed above. In particular, the present removable jaw assemblies can be easily manually attached to and detached from movable support members operably supported in a workholder base. Therefore, the subject removable jaw assembly addresses a number of problems commonly encountered when using other known workholder jaw arrangements. These and other details, objects and advantages will become further apparent as the following detailed description of the present preferred embodiment thereof proceeds.











BRIEF DESCRIPTION OF THE DRAWINGS




In the accompanying drawings, there are shown present preferred embodiments of the invention wherein like reference numerals are employed to designate like parts and wherein:





FIG. 1

is a partial cross-sectional elevational view of a preferred vise-like workholding apparatus having two removable jaw members of the present invention attached thereto;





FIG. 2

is a left end elevational view of the device depicted in

FIG. 1

;





FIG. 3

is a plan view of a preferred movable support member of the present invention;





FIG. 4

is a partial side elevational view of a preferred jaw member shown in cross-section in a first released position on the preferred support member depicted in

FIG. 3

;





FIG. 5

is a partial sectional view of the jaw member of

FIG. 4

in a released position on the support member;





FIG. 6

is a partial cross-sectional view of the jaw member of

FIG. 5

taken along line VI—VI in

FIG. 5

;





FIG. 7

is a partial side elevational view of another preferred jaw member attached to another preferred support member with the jaw member shown in cross-section;





FIG. 8

is a partial sectional view of the jaw member and support member of

FIG. 7

taken along line VIII—VIII in

FIG. 7

;





FIG. 9

is a diagram of a preferred method of the present invention;





FIG. 10

is a side elevational view of another preferred removable jaw member of the present invention attached to another preferred support member of the present invention with the jaw member shown in cross-section for clarity;





FIG. 11

is a partial sectional view of the jaw member and support member assembly depicted in

FIG. 11

taken along line XI—XI in

FIG. 10

;





FIG. 12

is a partial cross-sectional elevational view of another preferred vise-like workholding apparatus of the present invention;





FIG. 13

is a plan view of a preferred movable support member of the preferred workholding apparatus of

FIG. 12

;





FIG. 14

is an enlarged partial view of the ball and spring arrangement of the support member depicted in

FIG. 13

;





FIG. 15

is a bottom view of a preferred jaw member depicted in

FIG. 12

;





FIG. 16

is a cross-sectional view of the jaw member of

FIG. 15

taken along line XVI—XVI in

FIG. 15

;





FIG. 17

is a cross-sectional view of the jaw member of

FIGS. 15 and 16

taken along line XVII—XVII of

FIG. 15

;





FIG. 18

is an enlarged partial sectional view of the workholding apparatus depicted in

FIG. 12

;





FIG. 19

is a partial cross-sectional view of a preferred jaw member of the present invention attached to another preferred support member that is supported within a vertically mounted workholding apparatus;





FIG. 20

is a plan view of a preferred jaw member received on a tower portion of a preferred support member in a released position, with the jaw member shown in cross-section for clarity;





FIG. 21

is a cross-sectional plan view of a preferred jaw member attached to a tower portion of a preferred support member of the present invention;





FIG. 22

is a cross-sectional view of another preferred jaw member of the present invention;





FIG. 23

is a cross-sectional plan view of the jaw member of

FIG. 22

attached to the tower portion of another preferred support member;





FIG. 24

is an end elevational view of a workholding apparatus supporting a support member depicted in

FIG. 22

with a jaw member shown in cross-section prior to attachment to the tower portion of the support member; and





FIG. 25

is an end elevational view of the workholding apparatus and jaw member of

FIG. 24

shown in cross-section after the jaw member has been pressed onto the tower portion of the support member.











DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS




Referring now to the drawings for the purposes of illustrating present preferred embodiments of the invention only and not for purposes of limiting the same,

FIG. 1

illustrates preferred removable jaw members (


10


,


10


′) of the present invention received on the base


22


of a vise-like workholder


20


. The basic structure of the workholder


20


is similar to the workholding apparatus described in U.S. Pat. No. 5,022,636, issued Jun. 11, 1991 to George R. Swann, entitled “Workholding Apparatus”, the disclosure of which is herein incorporated by reference. As such, in the present “Detailed Description Of Preferred Embodiments”, the basic structure of the workholder


20


will be described in general terms, it being understood that the particular details of the workholder


20


construction, with the exception of those features which are described hereinbelow forming these embodiments of the present invention, may be gleaned from a review of that patent. In addition, the skilled artisan will readily appreciate that the workholders described herein are provided as examples of the types of workholders with which the removable jaw member embodiments of the present invention may be used. As such, the particular construction of the inventions described herein should not be construed to limit the breadth of protection afforded to the present embodiments described herein and recited in the claims hereof.




The vise-like workholder


20


generally comprises a base member


22


which is an elongated metallic structure typically fabricated from high strength aluminum or steel material. As can be seen from reference to

FIGS. 1 and 2

, a cavity


24


is machined along the longitudinal axis “A—A” of the base member


22


and defines a longitudinal slot


26


having two longitudinally extending side rail members


28


. In addition, a clamping assembly, generally designated as


30


, is provided for selective movement within the cavity


24


in the base member


22


. The clamping assembly


30


includes a first movable support member


32


and a second movable support member


32


′ which are each slidably received within the cavity


24


. As shown in

FIGS. 1 and 2

, a first jaw member


10


is preferably removably attached to the first movable support member


32


and a second jaw member


10


′ is preferably removably attached to the second movable support member


32


′.




The clamping assembly


30


also includes a screw shaft


51


that is received within the cavity


24


in the base member


22


. One end of the screw shaft


51


is provided with threads which are intended to engage a threaded bore


41


within the second movable support member


32


′. In addition, the screw shaft


51


includes means (not shown) for engaging and displacing the first movable support member


32


. The screw shaft


51


passes through the first movable support member


32


and has a socket


53


therein for facilitating the application of rotary motion to the screw shaft


51


.




A center jaw member


86


may also be attached to the base


22


between the first and second movable support members (


32


,


32


′) preferably by capscrews (not shown). See FIG.


1


. However, other fastening methods may also be used to attach the center jaw member


86


to the base


22


.




As can be seen in

FIG. 1

, the center jaw member


86


is preferably arranged on base


22


such that the first and second movable support members (


32


,


32


′) may move toward and away from the center jaw member


86


to clamp and unclamp workpieces


72


and


74


between the center jaw member


86


and first and second jaw members (


10


,


10


′). For example, when the screw shaft


51


is rotated clockwise, the first movable support member


32


is moved relative to the center jaw member


86


, thereby causing the first jaw member


10


to move toward the center jaw member


86


to clamp a first workpiece


72


therebetween. In addition, the clockwise rotation of the screw shaft


51


causes the second movable support member


32


′to move toward the center jaw member


86


to clamp a second workpiece


74


between the jaw members (


86


,


10


′).




As can be seen in

FIG. 2

, the side rail members


28


of the workholder base


22


define a planar worksurface (that has a slot


26


extending the length thereof), generally designated as


29


. In this embodiment, a shield


80


of the type disclosed in U.S. Pat. No. 5,442,844, issued on Aug. 22, 1995, entitled “Apparatus For Protecting the Internal Elements of a Workholding Apparatus”, the disclosure of which is also incorporated herein by reference, is utilized between jaws (


10


,


86


,


10


′) and the vise base


22


to prevent debris from accumulating in the slot


26


and/or cavity


24


. As can be seen in

FIG. 1

, a preferred debris shield


80


has a first longitudinal opening


82


therein for receiving a portion of movable support member


32


therethrough. Similarly, shield


80


also has a second longitudinal opening


84


for receiving a portion of the movable support member


32


′ therethrough. While the use of shield


80


is preferred, the skilled artisan will appreciate that the subject invention can function equally well on workholding apparatuses that do not employ such a shield.




The construction of a preferred first movable support member


32


and corresponding first removable jaw member


10


will now be described in detail, with it being understood that the second movable jaw member


10


′ and the second movable support member


32


′, respectively, are preferably constructed in the same manner. Referring now to FIGS.


2


-


6


, a preferred first movable support member


32


has a longitudinally extending body portion


34


that is adapted to be slidably received within the slot


26


of the vise base


22


. As can also be seen in

FIGS. 1

,


4


and


5


, the movable support member


32


has an attachment portion or tower


36


that is adapted to protrude above the planar worksurface


29


.




As shown in

FIG. 3

, in a preferred embodiment of the present invention, the tower


36


has a first end


38


, a second end


40


and two lateral sides (


42


,


44


). The body portion


34


has a longitudinal axis A′—A′ that extends therethrough. The skilled artisan will readily appreciate that the axes described herein are used for reference purposes only to describe preferred interrelationships of various elements of the present invention. Preferably, the first and second ends (


38


,


40


) of the tower portion


36


are substantially transverse to the axis A′—A′ and lateral sides (


42


,


44


) are substantially parallel to axis A′—A′. A retaining surface


46


is machined in the first end


38


of the tower


36


along axis B—B that is substantially transverse to axis A′—A′. See FIG.


3


. In a preferred embodiment, the retaining surface


46


is an undercut area provided at an approximate 45° angle (angle “C” in

FIG. 4

) relative to the planar worksurface


29


. Those of ordinary skill in the art will appreciate that other retaining features could also be successfully employed.




Also in a preferred embodiment, at least one and preferably two spring-biased latch members


50


are mounted within the tower portion


36


of a support member


32


with one latch member


50


being disposed in side


42


and one in side


44


. In the preferred embodiment depicted in

FIG. 3

, two opposing spring-biased latch members


50


are mounted in tower


36


such that they are coaxially aligned along axis D—D that is substantially transverse to axis A′—A′ and substantially parallel to axis B—B. Preferably, each spring-biased latch member


50


comprises a commercially available spring-loaded ball plunger assembly that includes a housing member


52


that is adapted to be threaded into a corresponding threaded bore


37


in tower


36


. Each housing member


52


contains a spring (not shown) that biases a retaining ball


54


in the direction represented by arrows (“E”, “E′”) in FIG.


3


.




In a preferred embodiment, jaw member


10


is fabricated from aluminum; however, jaw member


10


may be fabricated from a variety of other suitable materials such as steel and the like. As can be seen in FIGS.


4


-


6


, jaw member


10


has a clamping surface


12


and a bottom surface


14


that is adapted to slidably move on the shield


80


(if employed) or the worksurface


29


of the base


22


. In a preferred embodiment, a cavity


16


that is sized to receive the tower portion


36


of the support member


32


therein is provided in the bottom surface


14


of the jaw


10


. One end of the cavity


16


has an undercut groove


17


machined therein that is adapted to selectively mate with the angled retaining surface


46


machined in the tower portion


36


of the support member


32


. The skilled artisan will appreciate that the undercut groove


17


is machined at an angle “F” relative to the bottom surface


14


of the jaw


10


that is substantially equal to angle “C” of the retaining surface


46


of the tower


36


. See FIG.


6


.




As can be seen in

FIGS. 5

,


6


and


8


, each lateral side of the cavity


16


has a groove


60


and dimple


62


machined therein. In a preferred embodiment, groove


60


has a radius of 4 mm and is 2 mm deep at its center. Also, dimple


62


preferably has a radius of 4 mm and is 2 mm deep. We believe that these dimensions work well with a ball plunger


54


having a ball of 7 mm in diameter. As the present Detailed Description Proceeds, those of ordinary skill in the art will appreciate that the sizes and orientations of the grooves


60


and dimples


62


are dependent upon the size and orientations of the ball


54


of the spring-biased latch members


50


mounted in the tower


36


.





FIG. 7

illustrates a preferred orientation of dimple


62


(dimple


62


is depicted by a phantom line) relative to the ball of ball plunger


54


. For explanatory purposes, the vertically extending centerline of the ball of the ball plunger


54


is designated by “G”, while the horizontally extending centerline is designated by “H”. The vertically extending centerline of the dimple


62


is designated by “I” and the horizontally extending centerline is designated by “J”. In a preferred embodiment, the distance “K” between the vertically extending centerlines (G, I) is approximately 1 mm and the distance “L” between the horizontally extending centerlines (H, J) is approximately 1 mm. Those of ordinary skill in the art will understand that such orientation of the dimple


62


relative to the ball of the ball plunger


54


will result in the jaw member


10


being urged downward onto the shield


80


(if employed) or the planar worksurface


29


. Such downward force is represented by arrow “X” in FIG.


7


and serves to retain the undercut groove


17


of the jaw member


10


in engagement with the angled retaining surface


46


of the tower


36


and also serves to prevent infiltration of debris between the jaw member


10


and the shield


80


or the rails


28


.





FIG. 9

is a flow chart describing the method


90


of the present invention for attaching and detaching a jaw member


10


of the present invention to the workholding apparatus


20


.

FIGS. 4 and 5

illustrate a jaw


10


received on a corresponding tower


36


in a detached position. The reader will appreciate that the cavity


16


in the jaw


10


is sized such that the jaw may be placed vertically over the tower


36


as shown in FIG.


4


. Such step of vertically placing the jaw member


10


onto the tower


36


is represented as step


92


in FIG.


9


. When in the detached position, the balls


54


of the spring-biased latch members


50


are received in the corresponding grooves


60


in the jaw


10


. See FIG.


5


. After the jaw


10


is placed onto the tower


36


as shown in

FIGS. 4 and 5

, an axial force must be applied in the direction represented by arrow “M” along axis A′—A′ to move the jaw into an attached position. This step is represented as step


94


in FIG.


9


. The skilled artisan will readily appreciate that such axial force may be applied to jaw


10


or the base


22


of the workholding apparatus


20


when the jaw


10


is stationary in a myriad of different manners. For example the axial force may be manually applied to the jaw


10


or the base


22


provided that the spring force of the spring-biased latch members can be overcome by such force. In applications wherein the workholding assembly is mounted to a table that can be automatically moved relative to a machine tool spindle, the table can be moved to bring the jaw into contact with the spindle or other stationary object to apply the requisite axial force to the jaw. Similarly, the table could be retained in position and the machine tool then brought into contact with the jaw to urge it into the locked position depicted in

FIGS. 7 and 8

. Thus, the unique and novel method of attaching the removable jaw lends itself well to automatic jaw attachment and detachment which reduces jaw change over time and improves the efficiency of the machining operations.




When the jaw


10


is forced axially in the “M” direction, the balls


54


of the spring-biased latch members


50


are brought into engagement with the corresponding dimples


62


in the jaw cavity


16


to retain the jaw on the tower portion


36


. To remove the jaw member


10


from its corresponding tower portion


36


support member


32


, an axial force represented by arrow “N” is applied in an axial direction opposite to direction “M” to move the jaw member


10


to the position illustrated in

FIGS. 4 and 5

. This step of the present method is represented by


96


in FIG.


9


. The jaw


10


is then removed vertically from the tower


36


as represented by step


89


in FIG.


9


.




Those of ordinary skill in the art will further appreciate that the significant advantages enjoyed by the subject invention over the prior art can also be achieved when the spring-biased latch members are mounted in the jaw member. More specifically and with reference to

FIGS. 10

and


11


, there is shown another preferred embodiment of the present invention wherein a jaw member


110


is adapted for attachment to a tower portion


136


of a support member


132


. The reader will appreciate that, except for the differences specifically noted below, the jaw member


110


and the support member


132


are substantially identical to the jaw member


10


and support member


32


, respectively, as discussed above. In this embodiment, however, the spring-biased latch members


150


are mounted in the jaw member


110


such that their spring-loaded ball members


154


protrude into cavity


116


in the underside


114


of the jaw member


110


. As in jaw member


10


, an angled retaining groove


117


is machined into one end of the cavity


116


and is arranged to cooperate with an angled retaining surface


146


machined into one end of the tower


136


of support member


132


. It will be appreciated that, in a preferred embodiment, the angular orientations of groove


117


and retaining surface


146


are arranged as described above.




Spring-biased latch members


150


are mounted adjacent each lateral side of cavity


116


, coaxially along axis “D-D” as shown in FIG.


11


. As also shown in

FIGS. 10 and 11

, a groove


160


and a dimple


162


are machined into the tower


136


to cooperate with the corresponding ball members


154


of the spring-biased latch members


150


in the jaw member


110


. When the jaw member


110


is initially placed over the tower member


136


such that the tower member


136


is received within the cavity


116


, the balls


154


are received in their corresponding grooves


160


. To attach the jaw member


110


to the tower portion


136


, an axial force is applied to either the base


122


of the workholding apparatus


120


in which the support member


132


is received or the jaw member


110


to cause the jaw member


110


to be moved to the attached position depicted in

FIGS. 10 and 11

. To detach the jaw member


110


, the axial force is applied in the opposite direction. The skilled artisan will appreciate that the relationships of the centerlines of the spring-biased latch members


150


and their corresponding dimples


162


in the tower


136


are preferably identical to those relationships in the earlier discussed preferred embodiment, such that when the jaw member


110


or support member


132


is moved to the attached position, the balls


154


are offset relative to the centerlines of the dimples


162


and thus engage a side of the corresponding dimples


162


to retain the jaw member on the tower


136


. As was discussed above, those of ordinary skill in the art will understand that such orientation of the dimple


162


relative to the ball of the ball plunger


154


will result in the jaw member


110


being urged downward onto the shield


80


(if employed) or the planar worksurface


29


. Such downward force is represented by arrow “Z” in FIG.


10


and serves to retain the undercut groove


117


of the jaw member


110


in engagement with the angled retaining surface


146


of the tower


136


and also serves to prevent infiltration of debris between the jaw member


110


and the shield


80


or the rails


128


.




Another preferred embodiment is depicted in FIGS.


12


-


20


. Those elements that were described above and remain unchanged in this embodiment will be identified by their element numbers as set forth above. As such, it will be appreciated that the base member


22


as shown in

FIG. 12

has a worksurface


29


and a “first” longitudinal axis A—A. This embodiment employs a clamping assembly


230


that is received within the base member


22


of the workholder for selective movement within the cavity


24


in the base member


22


. The clamping assembly


230


includes a first movable support member


232


and a second movable support member


232


′ which are each slidably received within the cavity


24


. As shown in

FIG. 12

, a first jaw member


210


is preferably removably attached to the first movable support member


232


and a second jaw member


210


′ is preferably removably attached to the second movable support member


232


′.




The clamping assembly


230


also includes a screw shaft


251


that is received within the cavity


24


in the base member


22


. One end of the screw shaft


251


is provided with threads which are intended to engage a threaded bore


241


within the second movable support member


232


′. In addition, the screw shaft


251


includes means (not shown) for engaging and displacing the first movable support member


232


. The screw shaft


251


passes through the first movable support member


232


while the other end of the screw shaft


251


has a socket therein for facilitating the application of rotary motion to the screw shaft


251


.




As described above, a center jaw member


86


may also be attached to the base


22


between the first and second movable support members (


232


,


232


′). As can be seen in

FIG. 12

, the center jaw member


86


is preferably arranged on base


22


such that the first and second movable support members (


232


,


232


′) may move toward and away from the center jaw member


86


to clamp and unclamp workpieces


272


and


274


between the center jaw member


86


and first and second jaw members (


210


,


210


′). For example, when the screw shaft


251


is rotated clockwise, the first movable support member


232


is moved relative to the center jaw member


86


, thereby causing the first jaw member


210


to move toward the center jaw member


86


to clamp a first workpiece


272


therebetween. In addition, the clockwise rotation of the screw shaft


251


causes the second movable support member


232


′ to move toward the center jaw member


86


to clamp a second workpiece


274


between the jaw members (


86


,


210


′).




The construction of a preferred first movable support member


232


and corresponding first removable jaw member


210


will now be described in detail, with it being understood that the second movable jaw member


210


′ and the second movable support member


232


′ are preferably constructed in the same manner. Referring now to

FIGS. 13 and 18

, a preferred first movable support member


232


has a longitudinally extending body portion


234


that is adapted to be slidably received within the cavity


26


of the vise base


22


. As can also be seen in

FIGS. 13 and 18

, the movable support member


232


has an attachment portion or tower


236


that is adapted to protrude above the planar worksurface


29


.




As shown in

FIG. 13

, in a preferred embodiment of the present invention, the tower


236


has a first end


238


, a second end


240


and two lateral sides (


242


,


244


). The tower portion


236


has a second longitudinal axis A″—A″ that extends therethrough. Preferably, the first and second ends (


238


,


240


) of the tower portion


236


are substantially transverse to the axis A″—A″ and lateral sides (


242


,


244


) are substantially parallel to axis A″—A″. A retaining surface


246


is machined in the first end


238


of the tower


236


along axis B″—B″ that is substantially transverse to axis A″—A″. See

FIGS. 13 and 18

. In a preferred embodiment, the retaining surface


246


is provided at an approximate 45° angle relative to the planar worksurface


29


. Those of ordinary skill in the art will appreciate that other retaining features could also be successfully employed.




Also in a preferred embodiment, a spring-biased retainer latch assembly


250


is mounted within the tower portion


236


of a support member


232


. Preferably, a bore


253


is provided in tower portion


236


along axis D″—D″ which is substantially transverse to axis A″—A″ and substantially parallel to axis B″—B″. Received within the bore


253


is a spring


254


and two ball members


256


. To retain the ball members


256


within the bore


253


, an inwardly extending annular retaining protrusion


258


is preferably machined at each end of the bore


253


. See FIG.


14


. The skilled artisan will understand that the spring


254


biases the ball members


256


outwardly; however, the ball members


256


are retained within bore


253


by virtue of their contact with the corresponding annular protrusion


258


.




In a preferred embodiment, jaw member


210


is fabricated from aluminum; however, jaw member


210


may be fabricated from a variety of other suitable materials such as steel and the like. As can be seen in

FIGS. 15

,


16


and


18


, jaw member


210


has clamping surfaces (


212


,


213


) and a bottom surface


214


that is adapted to slidably move on the shield


80


(if employed) or the worksurface


29


of the base


22


. In a preferred embodiment, a cavity


216


that is sized to receive the tower portion


236


of the support member


232


is provided in the bottom surface


214


of the jaw


210


. In this preferred embodiment, each longitudinal end of the cavity


216


has an undercut groove


217


machined therein that is adapted to alternatively selectively mate with the angled retaining surface


246


machined in the tower portion


236


of the support member. That is, cavity


216


has “first” and “second” angled retaining grooves


217


machine therein as shown in FIGS.


15


-


17


. The skilled artisan will appreciate that the undercut grooves


217


are each machined at an angle relative to the bottom surface


214


of the jaw


210


that is substantially equal to the angle of the retaining surface


246


of the tower


236


.




As can be seen in

FIGS. 15 and 16

each cavity wall


261


of the cavity


216


has a centrally located engagement area in the form of a dimple


262


and two grooves (


264


,


266


) machined therein. In a preferred embodiment, (


264


,


266


) each has a radius of 4 mm and is 2 mm deep at its center. Also, dimple


262


preferably has a radius of 4 mm and is 2 mm deep. These dimensions work well with a ball members


256


that are 7 mm in diameter. As noted above, those of ordinary skill in the art will appreciate that the sizes and orientations of the dimple


262


and (


264


,


266


) are dependent upon the size and orientations of the ball members


256


. In a preferred embodiment, the vertical and horizontal centerlines (not shown) of the ball members


256


are offset from the corresponding vertical and horizontal centerlines of the dimple


262


(not shown) by 1 mm each in the manner described hereinabove such that when the jaw member


210


is attached to the tower portion


236


, the jaw member


210


is retained on the tower portion


236


and urged downward onto the shield


80


(if employed) or the worksurface


29


.




Also, those of ordinary skill in the art will appreciate that by providing undercut grooves


217


in each longitudinal end of the cavity


216


, the jaw member


210


can be attached to the tower portion


236


in two different orientations. For example, the jaw member


210


can be attached to the tower portion


236


such that the clamping surface


212


faces the center jaw


86


. In the alternative, the jaw member


210


can be attached to the tower portion


236


such that the clamping surface


213


faces the center jaw


86


. Such construction conveniently enables different notches, grooves, cut outs, etc. to be machined into the clamping surfaces to enable one jaw member


210


to be used to selectively clamp differently configured workpieces.




Also, today's competitive environment facing most machine shop owners requires optimum utilization of all machine tool assets to ensure maximum productivity and profitability. Depending upon the types and numbers of workpieces to be machined, oftentimes the machinist must utilize vertically-mounted workholding devices which enable more of the “machining envelope” of the machine tool to be utilized. Examples of such vertically-mounted workholding devices are manufactured by Chick Workholding Solutions, Inc. of 500 Keystone Drive, Warrendale, Pa. 15086 under the trademark MULTI-LOK™.




Those of ordinary skill in the art will appreciate that the preferred embodiments of the subject invention disclosed herein are well-suited for use with such vertically-mounted devices. However, if the jaw members are detached from their corresponding towers, the jaw members could accidentally fall off of their corresponding tower portions which could injure the machinist or attending personnel and/or damage the workholders and/or machine tools. As shown in

FIGS. 19 and 20

, to prevent such problem, a recessed groove


270


is preferably machined in the rear end of the tower portion


236


. As can be seen in those Figures, when the jaw


210


is in a released position, the corresponding undercut groove


217


engages the recessed groove


270


to prevent the jaw


210


from sliding off of the tower portion


236


.




Another preferred embodiment of the present invention is depicted in FIGS.


22


-


25


. In this preferred embodiment, jaw member


310


is fabricated from aluminum; however, jaw member


310


may be fabricated from a variety of other suitable materials such as steel and the like. As can be seen in

FIGS. 22 and 23

, jaw member


310


has clamping surfaces (


212


,


213


) and a bottom surface


314


that is adapted to slidably move on the shield


80


(if employed) or the worksurface


29


of the base


22


. In a preferred embodiment, a cavity


316


that is sized to receive the tower portion


236


of the support member


232


therein is provided in the bottom surface


314


of the jaw


310


. Each longitudinal end of the cavity


316


preferably has an undercut groove


317


machined therein that is adapted to selectively mate with the angled retaining surface


246


machined in the tower portion


236


of the support member


232


.




As can be seen in

FIGS. 22 and 23

, each lateral side of the cavity


316


has a centrally located dimple


362


machined therein that preferably has a radius of 4 mm and is 2 mm deep. These dimensions work well with a ball members


256


that are 7 mm in diameter. As noted above, those of ordinary skill in the art will appreciate that the sizes and orientations of the dimple


262


are dependent upon the size and orientations of the ball members


256


of the corresponding spring-biased latch assembly


250


mounted in the tower


236


. In a preferred embodiment, the vertical and horizontal centerlines (not shown) of the ball members


256


are offset from the vertical and horizontal centerlines of a corresponding dimple


262


by 1 mm each in the manner described hereinabove such that when the jaw member


310


is attached to the tower portion


236


, the jaw member


310


is retained on the tower portion


236


and urged downward onto the shield


80


(if employed) or the worksurface


29


.




To install the jaw


310


on a corresponding tower portion


236


, the jaw is aligned over the tower


236


as shown in FIG.


24


. Thereafter, a downward force is applied to the jaw member


310


until the bottom surface


314


is received on the shield


80


(if employed) or the worksurface


29


. Because the dimples


362


are not aligned vertically with the corresponding ball members


256


, the ball members


256


are biased into the bore


254


in the tower


236


. After the jaw member


310


is completely pressed onto the tower as shown in

FIG. 25

, the jaw member


310


is then longitudinally moved into the attached position as shown in FIG.


23


. In the alternative, the jaw member


310


can be attached to a corresponding tower portion


236


by placing the jaw member


310


on the tower portion


236


such that one of the undercut grooves


360


thereof engages the retaining surface


246


. Thereafter, a vertical or arcuate force is applied to the jaw member


310


. Initially, the ball members


256


will engage the inner walls of the cavity


316


and be biased within the bore


254


in the tower portion


236


until the jaw member


310


is forced into the attached position (

FIG. 23

) wherein the ball members


256


engage the corresponding dimples


262


.




While the preferred embodiments of the present invention have been disclosed herein in connection with movable jaws for vise-like workholders, the skilled artisan will appreciate that the present invention will work well for attaching a removable jaw to a non-movable support member. Thus, the present invention could be employed to attach removable jaws to movable and fixed support members of a vise-like workholding apparatus.




Accordingly, the present invention provides solutions to the aforementioned problems associated with vise-like workholding apparatuses. The present invention provides a removable jaw for use in connection with a vise-like workholder that is relatively inexpensive to manufacture when compared to other workholder jaws. Due to the unique manner of fastening the jaw to the vise, the jaws can be easily manually detached from the vise. While such advantages are apparent from the foregoing disclosure, it will be understood, however, that various changes in the details, materials and arrangements of parts which have been herein described and illustrated in order to explain the nature of the invention may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.



Claims
  • 1. A method of installing a jaw member on a vise-like workholding apparatus wherein the workholding apparatus has a worksurface and a longitudinal axis and a support member protruding above the worksurface and being configured to receive the jaw member thereon and means for selectively engaging the jaw member to retain it thereon, the method comprising:placing the jaw member onto the support member in a first direction substantially perpendicular to the worksurface such that at least a portion of the support member is received within a receiving cavity in the jaw member; and applying a first longitudinal force in a first longitudinal direction to the jaw member when the at least a portion of the support member is received within the receiving cavity to move the jaw member axially in the first longitudinal direction relative to the support member such that the means for selectively engaging engages a lateral side of the receiving cavity along an axis that is transverse to the longitudinal axis to attach the jaw member to the support member.
  • 2. The method of claim 1 wherein said first longitudinal force is applied manually.
  • 3. The method of claim 1 wherein said first longitudinal force is applied mechanically.
  • 4. The method of claim 1 wherein said applying comprises applying a first longitudinal force in a first longitudinal direction to the jaw member when the at least a portion of the support member is received within the receiving cavity to move the jaw member longitudinally such that a latch assembly in the support member engages a dimple in a lateral side of the receiving cavity along an axis that is transverse to the longitudinal axis.
  • 5. The method of claim 1 wherein the support member has a first retaining surface therein that is substantially transverse to the longitudinal axis and an undercut groove is provided in a longitudinal end of the receiving cavity and wherein when the means for selectively engaging engages the lateral side of the receiving cavity, the retaining surface engages the undercut groove in the receiving cavity.
  • 6. The method of claim 1 wherein the support member has a first retaining surface therein that is substantially transverse to the longitudinal axis and an undercut groove is provided in a longitudinal end of the receiving cavity and wherein said applying comprises applying a first longitudinal force in a first longitudinal direction to the jaw member when the at least a portion of the support member is received within the receiving cavity to move the jaw member longitudinally such that a latch assembly in the support member engages a dimple in a lateral side of the receiving cavity along the axis that is transverse to the longitudinal axis and the retaining surface is engaged with the undercut groove in the receiving cavity.
  • 7. The method of claim 1 further comprising disengaging the surface of the receiving cavity with the means for selectively engaging.
  • 8. The method of claim 1 further comprising:applying a second longitudinal force in a second longitudinal direction opposite to the first longitudinal direction to the jaw member to move the jaw member longitudinally such that a latch assembly in the support member disengages the lateral side of the receiving cavity; and removing the jaw member from the support member by applying a removal force to the jaw member in a second direction that is substantially perpendicular to the worksurface.
  • 9. The method of claim 4 further comprising:applying a second longitudinal force in a second longitudinal direction opposite to the first longitudinal direction to the jaw member to move the jaw member longitudinally such that the latch assembly in the support member disengages the dimple in the lateral side of the receiving cavity; and removing the jaw member from the support member by applying a removal force to the jaw member in a second direction that is substantially perpendicular to the worksurface.
  • 10. The method of claim 6 further comprising:applying a second longitudinal force in a second longitudinal direction opposite to the first longitudinal direction to the jaw member to move the jaw member longitudinally such that a latch assembly in the support member disengages the dimple in the lateral side of the receiving cavity and the retaining surface is disengaged with the undercut groove in the receiving cavity; and removing the jaw member from the support member by applying a removal force to the jaw member in a second direction that is substantially perpendicular to the worksurface.
  • 11. The method of claim 1 wherein a vertical groove and a dimple are provided in the lateral side of the receiving cavity and wherein said placing further comprises:aligning the vertical groove with a latch in the support member; and applying an installation force to the jaw member in the first direction substantially perpendicular to the worksurface such that at least a portion of the support member is received within the receiving cavity.
  • 12. The method of claim 11 wherein said engaging comprises applying a first longitudinal force in a first longitudinal direction to the jaw member when the at least a portion of the support member is received within the receiving cavity to move the jaw member longitudinally such that a latch assembly in the support member engages the dimple in a lateral side of the receiving cavity along the axis that is transverse to the longitudinal axis and the retaining surface is engaged with the undercut groove in the receiving cavity.
  • 13. A method of installing a jaw member on a vise-like workholding apparatus wherein the workholding apparatus has a worksurface and a longitudinal axis and a support member protruding above the worksurface and being configured to receive the jaw member thereon and means for selectively engaging the jaw member to retain it thereon, the method comprising:placing the jaw member onto the support member in a first direction substantially perpendicular to the worksurface such that at least a portion of the support member is received within a receiving cavity in the jaw member in a first released position; and applying a first longitudinal force in a first longitudinal direction to the jaw member when the at least a portion of the support member is received within the receiving cavity to move the jaw member axially in the first longitudinal direction relative to the support member such that the means for selectively engaging simultaneously engages two opposing lateral sides of the receiving cavity along an axis that is transverse to the longitudinal axis to attach the jaw member to the support member.
  • 14. The method of claim 13 wherein said applying comprises applying a first longitudinal force in a first longitudinal direction to the jaw member when the at least a portion of the support member is received within the receiving cavity to move the jaw member longitudinally such that a latch assembly in the support member simultaneously engages a dimple in each of two opposing lateral sides of the receiving cavity along an axis that is transverse to the longitudinal axis.
  • 15. The method of claim 13 wherein the support member has a first retaining surface therein that is substantially transverse to the longitudinal axis and an undercut groove is provided in a longitudinal end of the receiving cavity and wherein when the means for selectively engaging engages the two opposing lateral sides of the receiving cavity, the retaining surface engages the undercut groove in the receiving cavity.
  • 16. The method of claim 13 wherein the support member has a first retaining surface therein that is substantially transverse to the longitudinal axis and an undercut groove is provided in a longitudinal end of the receiving cavity and wherein said applying comprises applying a first longitudinal force in a first longitudinal direction to the jaw member when the at least a portion of the support member is received within the receiving cavity to move the jaw member longitudinally such that a latch assembly in the support member engages a dimple in each opposing lateral side of the receiving cavity along the axis that is transverse to the longitudinal axis and the retaining surface is engaged with the undercut groove in the receiving cavity.
  • 17. The method of claim 13 further comprising disengaging the opposing lateral sides of the receiving cavity with the means for selectively engaging.
  • 18. The method of claim 13 further comprising:applying a second longitudinal force in a second longitudinal direction opposite to the first longitudinal direction to the jaw member to move the jaw member longitudinally such that a latch assembly in the support member disengages the lateral sides of the receiving cavity; and removing the jaw member from the support member by applying a removal force to the jaw member in a second direction that is substantially perpendicular to the worksurface.
  • 19. The method of claim 4 further comprising:applying a second longitudinal force in a second longitudinal direction opposite to the first longitudinal direction to the jaw member to move the jaw member longitudinally such that a latch assembly in the support member simultaneously disengages the dimples in the lateral sides of the receiving cavity; and removing the jaw member from the support member by applying a removal force to the jaw member in a second direction that is substantially perpendicular to the worksurface.
  • 20. The method of claim 16 further comprising:applying a second longitudinal force in a second longitudinal direction opposite to the first longitudinal direction to the jaw member to move the jaw member longitudinally such that a latch assembly in the support member disengages the dimples in the lateral sides of the receiving cavity and the retaining surface is disengaged with the undercut groove in the receiving cavity; and removing the jaw member from the support member by applying a removal force to the jaw member in a second direction that is substantially perpendicular to the worksurface.
  • 21. The method of claim 13 wherein a vertical groove and a dimple are provided in each opposing lateral side of the receiving cavity and wherein said placing further comprises:aligning the vertical grooves with a latch in the support member; and applying an installation force to the jaw member in the first direction substantially perpendicular to the worksurface such that at least a portion of the support member is received within the receiving cavity.
  • 22. A method of installing a jaw member that has two clamping surfaces on opposing ends thereof on a vise-like workholding apparatus wherein the workholding apparatus has a worksurface, a longitudinal axis, a center jaw and a support member that protrudes above the worksurface and is selectively movable toward and away from the center jaw, the support member being configured to receive the jaw member thereon, the support member further having means for selectively engaging the jaw member to retain it thereon, the method comprising:placing the jaw member onto the support member in a first direction substantially perpendicular to the worksurface such that at least a portion of the support member is received within a receiving cavity in the jaw member and one of the clamping surfaces face the center jaw; applying a first longitudinal force in a first longitudinal direction to the jaw member when the at least a portion of the support member is received within the receiving cavity to move the jaw member axially in the first longitudinal direction relative to the support member such that the means for selectively engaging engages a lateral side of the receiving cavity along an axis that is transverse to the longitudinal axis to attach the jaw member to the support member in a first position wherein a clamping surface faces the center jaw; applying a second longitudinal force in a second longitudinal direction opposite to the first longitudinal direction to the jaw member to move the jaw member longitudinally such that the means for selectively engaging disengages the lateral side of the receiving cavity; removing the jaw member from the support member by applying a removal force to the jaw member in a second direction that is substantially perpendicular to the worksurface; replacing the jaw member onto the support member in the first direction substantially perpendicular to the worksurface such that at least a portion of the support member is received within a receiving cavity in the jaw member and the other clamping surface faces the center jaw; and reapplying the first longitudinal force in a first longitudinal direction to the jaw member when the at least a portion of the support member is received within the receiving cavity to move the jaw member axially in the first longitudinal direction relative to the support member such that the means for selectively engaging engages a lateral side of the receiving cavity along an axis that is transverse to the longitudinal axis to attach the jaw member to the support member in a second position wherein the other clamping surface faces the center jaw.
CROSS REFERENCE TO RELATED APPLICATIONS

This patent application is a divisional application of U.S. patent application Ser. No. 08/888,035, filed Jul. 3, 1997 now U.S. Pat. No. 5,921,534.

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