Pivoting fluid dispensing method

Information

  • Patent Grant
  • 6391387
  • Patent Number
    6,391,387
  • Date Filed
    Monday, November 22, 1999
    25 years ago
  • Date Issued
    Tuesday, May 21, 2002
    22 years ago
Abstract
A sealant dispensing system is disclosed which is capable of applying sealant material to irregularly shaped, i.e., non-circular, closure members. To accomplish this, the closure member is loaded onto a rotary chuck in a conventional manner. The sealant applying gun, however, is moveable relative to the end. In this manner, through a combination of rotation of the closure member and movement of the gun, the gun is able to follow the outline of a closure member of any shape. In order to allow non-circular closure members to be loaded onto a chuck, the chuck must first be stopped. After the closure member is loaded, chuck rotation is then initiated. In order to allow this selective chuck rotation, the chuck may be attached to a servo motor. An electromagnet may be located in proximity to each chuck of the sealant dispensing system. In this manner, the electromagnet may be activated during loading of the end of the closure member onto the chuck and then deactivated when it is time to unload the closure member from the chuck. In an indexing type sealant dispensing system, the shuttle mechanism may be driven by a cam device, rather than a conventional crank mechanism. The cam device allows the motion characteristics of the shuttle mechanism to be precisely controlled such that machine cycle time can be reduced.
Description




FIELD OF THE INVENTION




The present invention relates generally to a fluid dispensing system and method and, more particularly, to a sealant delivery system and apparatus for application of a sealant compound material to non-circular container lids and closures.




BACKGROUND OF THE INVENTION




It is conventional to apply sealant to the underside of container closure members in order to facilitate subsequent sealing attachment of the closure members to containers. Such sealant is normally applied in an annular pattern on the underside of each closure member in a manner such that, when the closure is attached to the container, the applied sealant will be located between the container rim and the closure member and, thus, seal the closure to the container.




One example of such a container closure is a can lid or “end”, as it is often referred to in the can-making industry. During the manufacture of a can end, a sealant, such as a latex sealant, is conventionally applied to the underside of a curl region of the end. After the can is filled, the end is seamed onto the upper flange of the can and the previously applied sealant material facilitates sealing between the curl area of the end and the flange of the can to which it is attached in order to prevent leakage.




Another example of such a container closure is a bottle cap or “crown”, as it is often referred to in the bottling industry. In a similar manner to the can end described above, bottle crowns are conventionally provided with a sealant material such that, when the crown is subsequently attached to a filled bottle, the sealant material will be located between the crown and the bottle, thus facilitating sealing attachment of the crown to the bottle.




To apply sealant to a container closure in a manner as described above, a sealant dispensing apparatus is generally used. Such an apparatus is often referred to in the industry, and may be referred to herein, as a “sealant dispensing gun” or simply a “gun”. Such sealant dispensing guns typically include a supply line which supplies liquid sealant to the gun, and a valve, such as a needle valve, for allowing the liquid sealant to be selectively dispensed from the gun. A container closure is generally supported by a chuck member which locates the closure adjacent the gun in the desired position. The closure is then rotated at a high speed by the chuck while the sealant dispensing gun valve is opened, thus resulting in an arcuate, even application of liquid sealant onto the underside of the closure. After application, the liquid sealant cures to form a solidified ring of resilient sealing material.




The extent of the rotational coverage of sealant on the closure may be adjusted by controlling the valve “dwell time” which is a measure of the time that the valve remains in its open position. Rotational coverage of a closure member with sealant is dictated by the valve dwell time relative to the rotational speed of the chuck and attached closure member. The dispense rate of sealant through the valve may also be controlled by adjusting the extent to which the needle valve opens.




Sealant dispensing guns are conventionally found in either stationary, indexing machines or in rotary machines. In an indexing machine, a sealant dispensing gun is stationarily mounted while the container closures to be coated are indexed through the machine. An example of such an indexing sealant dispensing machine for applying sealant to bottle crowns is described in U.S. Pat. No. 3,412,971 of McDivitt for ELECTRICALLY-CONTROLLED VALVE APPARATUS AND CONTROL CIRCUIT SUITABLE FOR USE THEREIN, which is hereby incorporated by reference for all that is disclosed therein.




In a rotary machine, a plurality of sealant dispensing guns are generally revolvingly mounted with respect to an axis. A rotary can lid feed mechanism is provided having a series of pockets which locate a closure member beneath each of the rotating guns. Each of the closure members is then sequentially lifted, engaged by a chuck member and rotated while the adjacent sealant dispensing gun applies sealant thereto. Examples of rotary sealant dispensing machines are set forth in U.S. Pat. No. 4,262,629 of McConnellogue et al. for APPARATUS FOR APPLICATION OF SEALANT TO CAN LIDS; U.S. Pat. No. 4,840,138 of Stirbis for FLUID DISPENSING SYSTEM; U.S. Pat. No. 5,215,587 of McConnellogue et al. for SEALANT APPLICATOR FOR CAN LIDS; U.S. Pat. No. 5,749,969 of Kobak et al. for FLUID DISPENSING SYSTEM; U.S. Pat. No. 6,010,740 of Rutledge et al. for FLUID DISPENSING SYSTEM and U.S. Pat. No. 6,113,333 of Rutledge et al. for APPARATUS AND METHOD FOR APPLYING SEALANT TO A CAN LID, which are all hereby incorporated by reference for all that is disclosed therein.




Some sealant dispensing guns include valves which are operated by cams and mechanical linkage arrangements. In these types of machines, the valve dwell time and the valve open limit are generally dictated by the specific physical cam and cam follower arrangement used. Accordingly, adjusting the valve dwell time or valve open limit in such machines generally requires a time consuming and expensive process of replacing various mechanical elements. Examples of such mechanical actuation arrangements are illustrated in U.S. Pat. Nos. 4,262,629 and 4,840,138, referenced above.




More common in recent years, however, are sealant dispensing guns in which the sealant dispensing gun valve is actuated by an electrical solenoid device or devices. In such guns, the valve dwell time is dictated not by mechanical linkages and cams, but instead by the amount of time that the valve opening solenoid is energized. Accordingly, the use of such electrical solenoid devices allows the valve dwell time of a sealant dispensing gun to be easily varied. Examples of sealant dispensing guns utilizing electrical solenoid valve actuation devices are illustrated in U.S. Pat. Nos. 3,412,971; 5,215,587 and 5,749,969, as previously referenced.




Since the cam actuation mechanism is eliminated in sealant dispensing guns having solenoid valve actuation devices, this type of gun generally also includes an adjustable mechanism for controlling the valve open limit. This adjustable mechanism may control the valve open limit by providing a movable stop for the valve stem or by moving the valve opening solenoid itself, or both.




In addition to solenoid valve actuation, some sealant dispensing guns also employ solenoid or motor actuated devices to adjust the valve open limit. Such guns allow remote control of the open limit and, thus, the rate at which sealant is dispensed from the gun when the valve is in its open position. Examples of sealant dispensing guns incorporating solenoid or motor actuated valve open limit devices are illustrated in U.S. Pat. Nos. 5,215,587 and 5,749,969, as previously referenced.




Although many closure members are circular, e.g., most soft drink can closure members, many closure members are irregularly shaped, i.e., are non-circular. Although the sealant dispensing systems described above generally work well, none of them are capable of applying sealant to irregular, i.e., non-circular, closure members. Accordingly, a need exists to provide a sealant dispensing system capable of applying sealant to irregular closure members.




Many existing sealant dispensing machines include magnets to assist in locating closure members on the machine when ferrous, e.g, steel, closure members, are to be coated with sealant. The magnets are generally located in conjunction with the chuck members such that the magnets tend to assist in locating the ferrous closure members on the chucks and maintaining them in place while sealant is applied. It has been found, however, that such magnets sometimes hinder the ability to remove the closure members from the chucks when coating has been completed.




In a stationary, indexing type machine, a shuttle mechanism typically serves to sequentially move uncoated closure members from a supply of closure members to the chuck of the sealant application mechanism. One limitation on the speed of an indexing machine is the length of time required to move a closure member into place on the chuck. Typically an indexing machine shuttle mechanism is driven by a crank device which, in turn, is driven by the main machine drive unit. The use of such a crank device inherently limits the speed of the shuttle mechanism and, thus, ultimately limits the speed at which the indexing type machine can operate.




Thus, it would be generally desirable to provide an apparatus and method which overcomes these problems associated with sealant dispensing devices as described above.




SUMMARY OF THE INVENTION




A sealant dispensing system is disclosed which is capable of applying sealant material to irregularly shaped, i.e., non-circular, closure members. To accomplish this, the closure member is loaded onto a rotary chuck in a conventional manner. The sealant applying gun, however, is moveable relative to the closure member. In this manner, through a combination of rotation of the closure member and movement of the gun, the gun is able to follow the outline of a closure member of any shape. To accomplish this, the gun may be mounted for pivotal movement. Alternatively, the gun may be mounted to allow translational, i.e., substantially linear movement. In either case, the movement may be achieved through the use of a servo motor. Alternatively, the movement may be achieved through the use of a linear actuator, such as a linear electromagnetic actuator.




In order to allow non-circular closure members to be loaded onto a chuck, the chuck must first be stopped. After the closure member is loaded, chuck rotation is then initiated. In order to allow this selective chuck rotation, the chuck may be attached to a servo motor.




An electromagnet may be located in proximity to each chuck of the sealant dispensing system. In this manner, the electromagnet may be activated during loading of the end of the closure member onto the chuck and then deactivated when it is time to unload the closure member from the chuck. Power to the electromagnet may be maintained during sealant application in order to ensure that the closure member remains in place on the chuck.




In an indexing type sealant dispensing system, the shuttle mechanism may be driven by a cam device, rather than a conventional crank mechanism. The cam device allows the motion characteristics of the shuttle mechanism to be precisely controlled such that machine cycle time can be reduced.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a partial cross-sectional elevation view of a fluid dispensing system.





FIG. 2

is a top plan view of an upper turret assembly of the fluid dispensing system of FIG.


1


.





FIG. 3

is a top plan view of a lower turret assembly of the fluid dispensing system of FIG.


1


.





FIG. 4

is a partial cross-sectional elevation detail view of a portion of the lower turret assembly of FIG.


3


.





FIG. 5

is a top plan view of a chuck member used in conjunction with the fluid dispensing system of FIG.


1


.





FIG. 6

is a partial cross-sectional front elevation detail view of a portion of the upper turret assembly of FIG.


2


.





FIG. 7

is a side elevation detail view of a portion of the upper turret assembly of FIG.


2


.





FIG. 8

is a view schematically illustrating the control of various components associated with the fluid dispensing system of FIG.


1


.





FIG. 9

is a view schematically illustrating the timing and operation of the fluid dispensing system of FIG.


1


.





FIG. 10

is a view schematically illustrating how linear displacements may be calculated for a non-circular closure member.





FIG. 11

is an exemplary graphical representation of dispensing gun opening linear displacement vs. chuck angular rotation.





FIG. 12

is a partial cross-sectional elevation view of a fluid dispensing system having six stations.





FIG. 13

is a top plan view of an upper turret assembly of the fluid dispensing system of FIG.


12


.





FIG. 14

is a top plan view of a lower turret assembly of the fluid dispensing system of FIG.


12


.





FIG. 15

is a side elevation view of a fluid dispensing system having a gun which moves in a linear fashion.





FIG. 16

is a front elevation view of the fluid dispensing system of FIG.


15


.





FIG. 17

is a schematic illustration of an indexing type fluid dispensing system.





FIG. 18

is an enlarged view of a portion of the indexing type fluid dispensing system of FIG.


17


.





FIG. 19

is a front elevation view of a fluid dispensing system having a pivoting dispensing gun which is driven by a linear actuator.





FIG. 20

is side elevation view of the fluid dispensing system of FIG.


19


.





FIG. 21

is detailed side elevation view, in partial cross-section, of the fluid dispensing system of FIG.


19


.





FIG. 22

is top plan view of the fluid dispensing system of FIG.


19


.





FIG. 23

is a front elevation view of a fluid dispensing system having a dispensing gun which moves in a linear fashion and which is driven by a linear actuator.





FIG. 24

is side elevation view of the fluid dispensing system of FIG.


23


.





FIG. 25

is top plan view of the fluid dispensing system of FIG.


23


.





FIG. 26

is a graph illustrating the movement of a conventional crank-driven shuttle mechanism.





FIG. 27

is schematic illustration graphically representing the movement of an improved cam-driven shuttle mechanism.











DETAILED DESCRIPTION OF THE INVENTION





FIGS. 1-27

, in general, illustrate a method of applying a fluid to a member


100


. The method includes providing a fluid dispensing mechanism


120


having an opening


122


therein; dispensing the fluid from the opening


122


in the fluid dispensing mechanism


120


onto the member


100


and pivoting the dispensing mechanism


120


about a pivot axis C—C.





FIGS. 1-27

also illustrate, in general, a fluid dispensing apparatus


10


for applying fluid to a member


10


. The fluid dispensing apparatus


10


includes: a support structure


12


; a fluid dispensing mechanism


120


having: a first opening in the fluid dispensing mechanism


120


the first opening being attached to a supply of fluid; a second opening


122


in the fluid dispensing mechanism


120


; a fluid flow path extending through the fluid dispensing mechanism


120


and connecting the first opening and the second opening


122


; and wherein the fluid dispensing mechanism


120


is pivotally attached to the support structure


12


about a pivot axis C—C.





FIGS. 1-27

also illustrate, in general, a method of applying a fluid to an article


100


. The method includes providing a first member


82


which is rotatable about a rotation axis B—B; providing an electromagnet


86


proximate the first member


82


; providing a fluid dispensing mechanism


120


located proximate the first member


82


; loading the article


100


onto the first member


82


; rotating the first member


82


about the rotation axis B—B; applying fluid to the article


100


with the fluid dispensing mechanism


120


; providing a first level of electrical current to the electromagnet


86


while the fluid is being applied to the article


100


.





FIGS. 1-27

also illustrate, in general, an apparatus


10


for applying fluid to a member


100


. The apparatus includes a support structure


12


; a support member


82


rotatably mounted to the support structure


12


about a rotation axis B—B; a fluid dispensing mechanism


120


attached to the support structure


12


, the fluid dispensing mechanism


120


including: a first opening in the fluid dispensing mechanism, the first opening being attached to a supply of fluid; a second opening


122


in the fluid dispensing mechanism


120


, the second opening


120


located proximate the support member


82


; a fluid flow path extending through the fluid dispensing mechanism


120


and connecting the first opening and the second opening


122


; an electromagnet


86


located in proximity to the support member


82


.





FIG. 1-27

also illustrate, in general, a method of applying a fluid to a member


500


. The method may include providing a fluid dispensing mechanism


610


having an opening therein; providing a linear actuator


660


operatively associated with the fluid dispensing mechanism


610


; dispensing the fluid from the opening in the fluid dispensing mechanism


610


onto the member


500


; and displacing the fluid dispensing mechanism


610


relative to the member


500


with the linear actuator


660


.





FIGS. 1-27

also illustrate, in general, a fluid dispensing apparatus


416


for applying fluid to a member


500


. The fluid dispensing apparatus


416


may include a fluid dispensing mechanism


610


having a first opening in the fluid dispensing mechanism


610


, the first opening being attached to a supply of fluid; a second opening in the fluid dispensing mechanism


610


and a fluid flow path extending through the fluid dispensing mechanism and connecting the first opening and the second opening. The fluid dispensing apparatus


416


may further include a linear actuator


660


operatively associated with the fluid dispensing mechanism


610


.





FIGS. 1-27

also illustrate, in general, an apparatus


410


for applying fluid to members


500


. The apparatus


410


may be of the type having a fluid dispensing mechanism


610


and a shuttle mechanism


496


for moving the members


500


from a first location


500


to a second location


482


adjacent the dispensing mechanism


610


. The apparatus


410


may include a support structure


412


. The shuttle mechanism


496


may be movably attached to the support structure


412


. A cam


512


may be operatively associated with the shuttle mechanism


496


.





FIGS. 1-27

also illustrate, in general, a method for applying fluid to members


500


. The method may include providing: a structure having a fluid dispensing mechanism


610


having a chuck member


482


operatively associated therewith; a first location adjacent a supply of the members


500


; a second location adjacent the fluid dispensing mechanism


610


and a shuttle mechanism


496


adapted to move the members


500


from the first location to the second location. The method may further include locating the shuttle mechanism


496


at the first location; loading at least one of the members


500


onto the shuttle mechanism


496


while the shuttle mechanism is located at the first location; moving the shuttle mechanism


496


, along with the member loaded thereon, in a first direction


505


toward the second location; causing the shuttle mechanism


496


to dwell at the second location and transferring the member from the shuttle mechanism


496


to the chuck


482


while the shuttle mechanism


496


is caused to dwell at the second location.




Having provided the general description above, the method and apparatus will now be described in further detail.





FIG. 1

illustrates a rotary sealant dispensing system


10


. Sealant dispensing system


10


may include a support structure


12


. A main turret assembly


13


may comprise a central shaft


15


, a lower turret assembly


14


and an upper turret assembly


16


. The main turret assembly


13


may be rotatably mounted within the support structure about the axis A—A, as illustrated in FIG.


1


and may be rotated via a conventional main drive motor


290


and gears


292


, illustrated schematically in FIG.


8


. Referring again to

FIG. 1

, a rotary table


18


may be fixedly attached to both the lower and upper turrets


14


,


16


and may, thus, be rotatable therewith about the axis A—A. Rotary table


18


may have an upper surface


19


as shown in

FIG. 4. A

cam


20


may be fixedly attached to the support structure


12


as illustrated. The dispensing system


10


may also include a plurality of sealant dispensing stations


50


, such as the individual stations


52


,


54


,


56


and


60


, e.g.,

FIGS. 2 and 3

, which are mounted so as to also be revolvable about the axis A—A.




Each of the sealant dispensing stations


50


may be substantially identical. Accordingly, only the station


54


will be described in detail herein, it being understood that the other stations may be formed in a substantially identical manner.

FIG. 4

illustrates the lower portion of the station


54


in greater detail. A pair of carriage guide rods


60


,


62


,

FIGS. 3 and 4

, may be fixedly attached to the lower turret assembly


14


at a lower end thereof and to the rotary table


18


at an upper end thereof. A carriage


70


may be slidingly attached to the guide rods


60


,


62


for reciprocal movement in the directions


66


,


68


of

FIG. 4. A

pair of cam followers


72


,


74


may be rotatably attached to the carriage


70


such that they engage the stationary cam


20


.




A servo motor


76


and a reduction gear box


78


may be mounted to the carriage


70


as shown. The servo motor


76


and gear box


78


may be arranged in a conventional manner such that the output shaft of the servo motor


76


engages with the input drive of the gear box


78


. An output shaft


80


of the gear box


78


may be attached to a chuck


82


as shown. As can be appreciated, activation of the servo motor


76


will, through the reduction gear box


78


, cause rotation of the chuck


82


about the rotational axis B—B. Servo motor


76


may be a conventional servo motor and may, for example, be of the type commercially available from Allen Bradley Company of 1201 S. Second Street, Milwaukee, Wis. 53204 and sold as Model No. N-2304-1-F00AA. Gear box


78


may be a conventional reduction gear box and may, for example, be of the type commercially available from CGI, Inc. of 3400 Arrowhead Drive, Carson City, Nev. 89706 and sold as Model No. NEMA23—9:1 Planetary Gearhead.




Chuck


82


may be configured to receive a closure member


100


, such as a can end. Closure member


100


may include a flange portion


102


as shown.

FIG. 5

illustrates the chuck


82


in plan view. As can be appreciated, the chuck


82


may by shaped to correspond to the shape of the closure member being handled by the sealant dispensing system


10


. The chuck


82


may, for example, have an oblong-shape as illustrated in

FIG. 5

when a closure member of corresponding oblong shape is being handled by the system


10


. It is to be understood, however, that the specific shape of the chuck


82


is illustrated in

FIG. 5

for exemplary purposes only. The sealant dispensing system


10


could be used in conjunction with closure members of any shape and the chuck


82


could readily be adapted to fit a closure member of any shape.




Referring to

FIG. 4

, an electromagnet


86


may be mounted to the carriage


70


in a non-rotatable fashion as shown. Electromagnet


86


may be formed in substantially the shape of an annulus.





FIG. 6

illustrates the upper portion of the station


54


in greater detail. Referring to

FIG. 6

, a sealant dispensing gun


120


may be provided as shown. Sealant dispensing gun


120


may be any conventional type of sealant dispensing gun and may, for example, be an electronic sealant dispensing gun of the type disclosed in U.S. Pat. No. 5,749,969 or in U.S. patent application Ser. No. 08/941,855, previously referenced.




Sealant dispensing gun


120


may include a sealant dispensing opening


122


. The gun


120


may be attached to a supply of sealant material via a conduit, not shown, in a conventional manner. As can be appreciated with reference to

FIG. 6

, when a closure member


100


is mounted on the chuck


82


, as shown, the dispensing gun opening


122


will be located adjacent the flange portion


102


of the closure member


100


and will, thus, be in position to apply sealant material to the flange


102


. As can further be appreciated, when the closure member


100


is a circular closure member, merely rotating the member


100


about the axis B—B will cause all portions of the flange


102


to pass directly beneath the sealant gun opening


122


. The sealant dispensing gun


120


is, thus, able to apply sealant material to the entire flange


102


.




In the case however, where an irregular closure member, such as the oblong member


100


, is to be coated, mere rotation of the member about the axis B—B will not cause all portions of the flange


102


to pass beneath the opening


122


. Accordingly, to facilitate applying sealant to irregular closure members, the gun


120


may be mounted for pivoting movement about the axis C—C as illustrated in

FIGS. 6 and 7

. Accordingly, the gun opening


122


is able to move in the arcuate directions generally indicated by the arrows


124


,


126


, FIG.


6


. As can be appreciated, the combination of the rotation of the closure member


100


about the axis B—B and the pivoting of the gun


120


about the axis C—C allows the gun opening


122


to follow the flange portion of a closure member of any shape and, thus, apply sealant material thereto.




As can be appreciated, the interaction of the stationary cam


20


and the revolving cam followers


72


,


74


,

FIG. 4

, will cause the carriage


70


and, thus, the attached chuck


82


, to move in an upward direction


66


and a downward direction


68


between a raised position as illustrated, for example, with respect to the station


54


in

FIG. 1 and a

lowered position as illustrated, for example, with respect to the station


58


in FIG.


1


. As can be seen from

FIG. 1

, the chuck of the station


54


is raised above the upper surface


19


of the rotary table


18


such that the gun opening


122


,

FIG. 4

, is located proximate the closure member flange portion


102


to facilitate the dispensing of sealant from the gun onto the flange portion


102


. Referring again to

FIG. 1

, the chuck of the station


58


, however, is flush with the upper surface


19


and retracted from the gun opening to facilitate the loading of a closure member onto the chuck of the station


58


in a manner as will be described in further detail herein.




Referring to

FIGS. 2

,


6


and


7


, the pivotal mounting of the gun


120


will now be described in further detail. The gun


120


may be attached to a cradle member


200


. A bracket


210


may include an upper portion


212


and a lower portion


214


as best shown in FIG.


6


. Bracket lower portion


214


may be attached to the upper turret


16


via a pair of bolts


216


,


218


. Bracket upper portion


212


may include a pair of forwardly extending yoke members


220


,


222


as best shown in

FIGS. 2 and 7

. Cradle member


200


may be pivotally attached to the yoke members


220


,


222


via a pair of pivot pins


224


,


226


, respectively. As can be appreciated, mounted in this manner, the cradle


200


and, thus, the gun


120


is able to pivot about the axis C—C,

FIG. 7

in the directions indicated by the arrows


124


,


126


, FIG.


6


. Accordingly, the gun


120


is pivotally mounted to the upper turret


16


. The axis C—C may be substantially perpendicular to the chuck rotational axis B—B,

FIG. 4

, and to the main turret rotational axis A—A, FIG.


1


.




Referring, for example, to

FIG. 7

, a servo motor


230


may be attached to a right angle gear reducer


232


as shown. Right angle gear reducer


232


, in turn may be attached to the bracket


210


via a connection bracket


236


,

FIGS. 2 and 7

. In this manner, the servo motor


230


and gear reducer


232


are rigidly attached to the bracket


210


and, thus, to the upper turret


16


. Referring again to

FIG. 7

, the output shaft


234


of the gear reducer


232


may be connected to a pivot coupling


238


which, in turn may be fixedly attached to the cradle


200


. As can be appreciated, the arrangement described above allows the servo motor


230


to cause pivoting movement of the gun


120


about the axis C—C as previously described.




Servo motor


230


may be a conventional servo motor and may, for example, be of the type commercially available from Allen Bradley Company of 1201 S. Second Street, Milwaukee, Wis. 53204 and sold as Model No. Y-10021-H00AA. Gear box


232


may be a conventional right angle reduction gear box and may, for example, be of the type commercially available from CGI, Inc. of 3400 Arrowhead Drive, Carson City, Nev. 89706 and sold as Model No. NEMA17 —18:1 Right Angle Gearhead.





FIG. 8

schematically illustrates the connection and control of the various components described above. Referring to

FIG. 8

, a main drive motor


290


may be drivingly attached to the main turret


13


via a series of gears


292


in a conventional manner. Accordingly, the motor


290


and gears


292


are able to cause rotation of the main turret assembly about the axis A—A.




Referring to

FIG. 1

, a controller


250


may, for example, be located as shown. Referring to

FIG. 8

, the controller


250


may be connected to the gun


120


via a connection


252


, thus allowing the controller


250


to control the operation of the gun


120


(e.g., the starting and stopping of sealant dispensing) in a conventional manner. A proximity sensor


254


may be located as shown. A rotating proximity sensor target


256


may be located in proximity to the sensor


254


and may be attached to the system main turret assembly


13


such that it rotates therewith. Accordingly, the sensor


254


is able to determine the angular displacement of the main turret assembly about the axis A—A. A connection


257


may extend between the sensor


254


and an electrical rotary union device


260


. A power supply connection


262


may also extend into the rotary union device


260


for the purpose of delivering power to the system. From the rotary union device


260


, both the power connection


262


and the sensor connection


256


may extend upwardly through the shaft


264


to the controller


250


. The controller


250


may be connected via a connection


266


to a plurality of motion controllers


268


, such as the individual motion controllers


270


,


272


. One motion controller may be provided for each of the servo motors previously described.




Referring again to

FIG. 8

, a connection


274


may extend between the individual motion controller


270


and a servo motor controller


276


. An encoder cable


278


may extend between the servo motor


230


and the motion controller


270


in order to supply a signal to the motion controller


276


indicating the angular position of the servo motor


230


. A power cable


280


may extend between the motion controller


276


and the servo motor


230


in order to selectively supply power to the servo motor


230


.




A connection


282


may extend between the individual motion controller


272


and a servo motor controller


284


. An encoder cable


286


may extend between the servo motor


76


and the motion controller


284


in order to supply a signal to the motion controller


284


indicating the angular position of the servo motor


76


. A power cable


288


may extend between the motion controller


284


and the servo motor


76


in order to selectively supply power to the servo motor


76


.




A connection


296


may extend between the controller


250


and the electromagnet


86


in order to allow the controller


250


to selectively activate the electromagnet


86


.




As can be appreciated from the above, the controller


250


is able to determine the angular displacement of the main turret assembly via the proximity sensor


254


and connection


257


. Based upon this angular displacement information, the controller


250


may selectively activate the gun


120


, the servo motors


76


,


230


and the electromagnet


86


in a manner as will be described in further detail herein.




For explanatory purposes, the above connections have been described with respect to the station


54


. It is to be understood that similar connections will exist for each of the stations


50


in the sealant dispensing system


10


.





FIG. 9

schematically illustrates the operation and timing of the sealant dispensing system


10


, as will now be described in detail.




Closure members


100


are brought into the sealant dispensing system


10


in a vertical stack


140


and enter a downstacker


150


which may, for example, be of conventional design. The downstacker


150


separates the bottom-most closure member


100


in the stack


140


and drops it into a rotatable starwheel mechanism


160


. Starwheel mechanism


160


may include a plurality of pockets


162


, such as the individual pockets


164


,


166


,


168


. The pockets


162


may be sized and shaped to correspond to the size and shape of the closure members


100


being handled by the sealant dispensing system


10


. Starwheel mechanism


160


may, for example, be of conventional design.




Continuing with the description of operation, the starwheel mechanism


160


moves a closure member


100


into alignment over the chuck


82


,

FIG. 4

, of the station


58


as shown in FIG.


9


. At the point of tangency, where the closure member


100


transfers from the starwheel mechanism


160


to the station


58


, the chuck


82


will be flush with the top surface


19


,

FIG. 4

, of the rotary table


18


. At this point, the rotation of the chuck


82


will also be stopped in order to allow the loading of the closure member


100


onto the chuck


82


. The use of a servo motor, e.g., the servo motor


76


,

FIG. 4

, allows rotation of the chuck


82


to be stopped in this manner. Stopping chuck rotation is critical to the loading of non-circular closure members. Although circular closure members are conventionally loaded onto rotating circular chucks, it is not possible to load a non-circular closure member onto a rotating chuck. The servo motor may be instructed, by the system controller


250


,

FIG. 8

, to stop the rotation of the chuck


82


such that the chuck


82


is aligned with the orientation of the closure member being transferred from the starwheel


160


as shown in FIG.


9


.




After the closure member is loaded onto the chuck


82


of the station


58


, as described above, continued revolution of the sealant dispensing system


10


about the axis A—A, will cause the station


58


to advance in the direction indicated by the arcuate arrow


170


in FIG.


9


. This motion, in turn, will cause the chuck


82


of the station


58


to begin to rise and, thus, engage the closure member previously loaded. As previously described, this rise of the chuck


82


is caused by the interaction of a stationary cam


20


and revolving cam followers


72


,


74


, FIG.


4


.




When the chuck


82


nears its fully raised position, the servo motor


76


, e.g.,

FIG. 4

, will be instructed by the system controller


250


to begin rotating the chuck. At this point, the servo motor


230


, e.g.,

FIG. 6

, will be instructed by the system controller


250


to begin pivoting the gun


120


about the axis C—C, thus, causing the gun opening


122


to follow the flange portion


102


of the closure member


100


. Sealant material may then be dispensed from the gun


120


for about two full revolutions of chuck rotation.




As an example of operation, the chuck could make three full revolutions from start to stop. The first one-half revolution may allow for acceleration of the chuck to full speed. For the next two full revolutions, at full speed, sealant may be dispensed. The final one-half revolution may be for deceleration of the chuck


82


to a stop.




After sealant dispensing is completed, the chuck


82


will begin to lower to the level of the upper surface


19


. When the chuck is fully lowered, the closure member may be removed from the non-rotating chuck


82


by an exit conveying device


180


,

FIG. 9

, which may, for example, be of conventional design. Exit conveying device


180


may, for example, comprise a pair of guide rails


182


,


184


as shown. As in the case of loading the closure member onto the chuck, it is also critical for proper unloading of a non-circular closure member that rotation of the chuck


82


first be stopped.




Referring to

FIG. 9

, the chuck


82


may, for example, begin rising at the rotational load point “A” and may continue to rise until it reaches its upward most extent at rotational point “C” which may, for example, be about 35 degrees past the load point “A”. At the point “B”, which may be about 8 degrees past the load point “A”, the electromagnet


86


may be energized. At the point “C”, the servo motor


76


may begin to accelerate the chuck


82


for a half rotation, as described above. This acceleration may continue for about 17.5 degrees past the point “C” until the point “D” is reached. Also at the point “C”, the servo motor


230


is activated to cause the gun opening


122


to begin following the contour of the closure member flange


102


. At the point “D”, the servo motor


76


may begin two full speed rotations of the chuck


82


. The gun opening


122


will continue to follow the contour of the flange


102


and sealant is dispensed from the gun. At the point “E”, which may be about 120 degrees from the point “D”, the servo motor


76


may begin to decelerate the chuck


82


and the dispensing of sealant from the gun will cease. The gun opening


122


, however, will continue to follow the contour of the flange


102


until the point “F” is reached at which time the chuck will have completely stopped rotation. The point “F” may be about 17.5 degrees from the point “E”. At the point “F”, the chuck will begin to drop to its retracted position. Also, at the point “F”, the gun opening


122


may stop following the contour of the closure member flange


102


. At the point “G”, which may be about 27 degrees from the point “F”, the electromagnet


86


may be de-energized to facilitate unloading of the closure member. At the unload point “H”, which may be about 8 degrees from the point “G”, the chuck has reached its fully retracted position and the closure member may be unloaded by the exit conveying device


180


.




The system controller


250


may be programmed to cause the servo motor


76


to accelerate, rotate a predetermined number of rotations at a predetermined speed, decelerate and stop. As previously described, each of the stations


50


has its own servo motor


76


. The servo motor start/stop and other timing points described above may be controlled by the system controller


250


based upon an input signal


257


,

FIG. 8

from the proximity sensor


254


. In this manner, the servo motors associated with each of the stations


50


may, in effect, be “laved” to the main turret drive motor


290


.




As previously described, an electromagnet


86


may be associated with each of the stations


50


. Each of the electromagnets may be controlled by the system controller


250


. The electromagnets may be used to hold closure members made, for example, of steel in place on the chucks


82


. The electromagnets may be timed to be energized and de-energized at predetermined points of rotation of the main turret. The use of electromagnets, as described herein, has been found to have various advantages over the use of permanent magnets. The use of electromagnets, for example, facilitates loading of closure members onto the chuck


82


. It has been found that using permanent magnets sometimes interferes with the loading of closure members in that the permanent magnet tends to drag the closure member and, thus, not allow it to properly align with the chuck before the chuck is lifted. It has been found that using permanent magnets also sometimes interferes with the unloading of closure members since the permanent magnets tend to keep the closure member stuck on the chuck. This, in turn, sometimes causes the closure members to jam beneath the exit conveying device guide rails


182


,


184


. The use of electromagnets overcomes these problems associated with permanent magnets because the electromagnets can be selectively turned on and off as described above.




As described above, the system controller


250


controls the rotation of the chuck


82


(via the servo motor


76


) and the pivoting motion of the gun


120


(via the servo motor


230


). The combination of these motions dictates the profile that the opening


122


of the gun


120


will follow. Accordingly, it is necessary to program the controller


250


for the specific size and shape of a particular closure member to be coated with the system


10


. First, however, it is necessary to calculate the linear displacement required from the gun


120


relative to the rotation of the closure member and chuck


82


.





FIG. 10

graphically illustrates how this calculation may be made for an exemplary closure member


100


.

FIG. 10

illustrates the closure member


100


having a flange portion


102


, as previously described. The line


300


represents the desired center line of sealant to be applied to the flange


102


. A plurality of lines


302


may be drawn from the center of the closure member, which may correspond to the axis B—B previously described, and the line


300


. The lines


302


may, for example be drawn in one degree increments over a range of 90 degrees, although only a few lines are shown in

FIG. 10

for illustration purposes. The line


303


may correspond to the zero degree rotational point of the chuck


82


for calculation purposes.




The length of each of the lines


302


represents the required linear displacement of the dispensing gun opening


122


relative to the center of the closure member for each degree of angular displacement of the chuck


82


. The length of each of the lines


302


may be either measured or calculated as will be readily apparent to one skilled in the art. Once the length of each of the lines


302


is determined, a table may be generated relating angular displacement of the chuck


82


to the required linear displacement of the gun opening


122


.




It is noted that the above length determination has been described using 1 degree increments for exemplary purposes only. Any other interval may alternatively be used in order to achieve the desired resolution. It is to be understood that linear displacements need only be calculated for 90 degrees of rotation since the closure member illustrated in

FIG. 10

is symmetrical about two axes.





FIG. 11

is a graphical illustration of the dispensing gun opening linear displacement vs. chuck angular displacement for the exemplary end illustrated in FIG.


10


. Referring to

FIG. 11

, angular displacement of the chuck


82


about the axis B—B,

FIG. 10

, is measured along the x-axis


304


of the graph, with the point


303


corresponding to the zero degree rotational point of the chuck


82


and the point


307


corresponding to the 360 degree rotational point of the chuck


82


. Linear displacement of the dispensing gun opening


122


from the axis B—B,

FIG. 10

, is measured along the y-axis


305


of the graph of FIG.


11


. Accordingly, the line


306


graphically illustrates the linear displacement of the dispensing gun opening


122


relative to the angular displacement of the chuck


82


.




Using conventional trigonometric practices, the dispensing gun opening linear displacement information, as illustrated, for example, in

FIG. 11

, can be used to calculate the required angular displacement of the gun


120


about the axis C—C,

FIG. 6

, relative to the angular displacement of the closure member


100


about the axis B—B. As can be appreciated, this information can readily be used to program the controller


250


with respect to the closure member


100


.




With the exception of the improvements described herein, the structure and operation of the sealant dispensing system


10


may, for example, be substantially identical that described in U.S. Pat. Nos. 4,262,629; 4,840,138; 5,215,587; or 5,749,969, previously referenced.




It is noted that the sealant dispensing system


10


has been described herein as having four stations for exemplary purposes only. The sealant dispensing system


10


could, alternatively have any number of stations.

FIGS. 12-14

, for example, illustrate a sealant dispensing system


10


′ having six stations


50


′. Other than the number of stations, the system depicted in

FIGS. 12-14

may be substantially similar to that of

FIGS. 1-3

.




It is noted that the sealant dispensing system


10


may also be used in a single station, indexing machine. An example of such an indexing machine is the type commercially available from WR Grace Company of Lexington, Mass. and sold as a “D&A Mark 70” model.




The sealant dispensing system


10


has been described herein having a pivoting gun


120


. The system could, however, instead use a gun which moves in a linear fashion.

FIGS. 15 and 16

illustrate a translational or linear motion gun sealant dispensing system


320


. Referring now to

FIGS. 15 and 16

, a gun


321


may be mounted on a carriage


322


. The gun


321


may be substantially identical to the gun


120


previously described herein. The carriage


322


may be mounted on a pair of guide rails


324


,


326


such that the carriage


322


and attached gun


321


are able to move in the linear directions indicated by the arrow


328


in

FIG. 17. A

servo motor


330


may be attached, via a reduction gearbox


332


, to a drive pulley


334


. A timing belt


336


may be engaged around the drive pulley


334


and an oppositely disposed pulley


338


. As can be appreciated, actuation of the servo motor


330


will cause the gun


321


to move in the linear directions


328


.




A servo motor


340


may be attached to a chuck


342


which is adapted to receive a non-circular closure member


344


. Closure member


344


may, for example, be substantially identical to the closure member


100


previously described. As can be appreciated, activation of the servo motor


340


will cause the chuck


342


and the closure member


344


to rotate about the rotational axis D—D.




In this manner, the system


320


is capable of applying sealant to non-circular closure members in a similar manner to the system


10


previously described. Specifically, the combination of rotational movement about the axis D—D and linear movement in the directions


328


allows the gun


321


to coat closure members of any shape.




The linear motion system


320


may, in all other respects operate in a substantially similar manner to that described above with respect to the system


10


and may, for example, be used in either a multiple (e.g, four or six) station rotary machine or in a single station indexing machine.




The pivoting gun variation previously described is advantageous relative to the linear motion gun variation in that, in the pivoting gun variation, less force is required to move the gun since the pivot point C—C is chosen to pass through the approximate center of gravity of the gun. In the linear gun variation, a large mass must be moved over a relatively large distance.




The linear motion gun variation, however, is advantageous in that the gun opening does not move in an arcuate fashion and, thus, the dispensing angle of the gun remains constant relative to the closure member.





FIG. 17

schematically illustrates a further indexing type sealant dispensing system


410


. Sealant dispensing system


410


may include a support structure


412


. A lower assembly


414


and an upper assembly


416


may be attached to the support structure


412


.




Lower assembly


414


will now be described in further detail. With reference to

FIG. 17

, lower assembly


414


may include a pair of guide rods (only the guide rod


460


is visible in

FIG. 17

) which may be fixedly attached to the support structure


412


. A carriage


470


may be slidingly attached to the guide rods for reciprocal movement in the directions


466


,


468


. The carriage


470


may be attached, via a drive arm


472


to a cam box


474


at a rotation point


471


. Cam box


474


may include an input gear


475


as shown.




A servo motor


476


and a reduction gear box


478


may be mounted to the carriage


470


as shown. The servo motor


476


and gear box


478


may be arranged in a conventional manner such that the output shaft of the servo motor


476


engages with the input drive of the gear box


478


. An output shaft


480


of the gear box


478


may be attached to a chuck


482


as shown. As can be appreciated, activation of the servo motor


476


will, through the reduction gear box


478


cause rotation of the chuck


482


about the rotational axis E—E.




Servo motor


476


may be a conventional servo motor similar to the servo motor


76


described previously. Servo motor


476


may, for example, be of the type commercially available from Allen Bradley Company of 1201 S. Second Street, Milwaukee, Wis. 53204 and sold as Model No. N-2304-1-F00AA. Gear box


478


may be a conventional reduction gear box similar to the reduction gear box


78


previously described. Gear box


478


may, for example, be of the type commercially available from CGI, Inc. of 3400 Arrowhead Drive, Carson City, Nev. 89706 and sold as Model No. NEMA23—9:1 Planetary Gearhead.




Chuck


482


may be configured to receive a closure member, such as the closure member


100


, previously described. Chuck


482


may, for example, be substantially identical to the chuck


82


previously described.




Referring again to

FIG. 17

, in operation, rotation of the input gear


475


of the cam box


474


will cause the drive arm


472


to rotate about the rotation point


471


in the directions indicated by the arrow


477


. This movement, in turn, will cause the carriage


470


(along with the attached servo motor


476


, gear box


478


and chuck


482


) to move along the guide rod


460


in the directions


466


,


468


. The drive arm


472


may, for example, rotate through about 10 degrees of movement. This exemplary 10 degree movement of the drive arm


472


will result in a translational movement of the carriage


470


(and the attached servo motor


476


, gear box


478


and chuck


482


) of about 0.44″ in the directions indicated by the arrows


466


,


468


.




The sealant dispensing system


410


may also include a downstacker device


550


which is driven by an input gear


552


, as shown. In operation, the downstacker device


550


serves to feed closure members, such as the closure members


500


schematically illustrated in

FIG. 17

, to the upper surface


413


of the support structure


412


.




With reference to

FIGS. 17 and 18

, lower assembly


414


may further include a pair of guide rods (only the guide rod


488


is visible in

FIG. 17

) which may be fixedly attached to the support structure


412


via a plurality of support blocks


490


, such as the individual support blocks


492


,


494


. A carriage


498


may be slidingly attached to the guide rods for reciprocal movement in the directions


504


,


505


. The carriage


498


may be attached, via a link arm


508


and a drive arm


510


to a cam box


512


at a rotation point


513


. Cam box


512


may include an input gear


514


as shown.




A shuttle mechanism


496


may be mounted to the carriage


498


as shown, for example, in FIG.


17


. In operation, rotation of the input gear


514


of the cam box


512


will cause the drive arm


510


to rotate about the rotation point


513


in the directions indicated by the arrow


515


. This movement, in turn, will cause the carriage


498


(which is connected to the drive arm


510


via the link arm


508


), along with the attached shuttle mechanism


496


, to move along the guide rod


488


in the directions indicated by the arrows


504


,


505


. The drive arm


515


may, for example, rotate through about 30 degrees of movement. This exemplary 30 degree movement of the drive arm


472


will result in a translational movement of the carriage


470


(and the attached shuttle mechanism


496


) of about 5.56″ in the directions indicated by the arrows


504


,


505


.




With reference, again to

FIG. 17

, lower assembly


414


may also include a motor


530


, operatively attached to a gearbox


532


. Gearbox


532


may include an output gear


534


as shown. Lower assembly


414


may further include a drive shaft


536


which is rotatable about an axis F—F. Drive


35


shaft


536


may include an input gear


538


, a first output gear


540


and a second output gear


542


. Drive shaft input gear


538


may be operatively engaged with the output gear


534


of the gearbox


532


. In this manner, the motor


530


and gearbox


532


may serve to rotatably drive the drive shaft


536


about the axis F—F. First output gear


540


of the driveshaft


536


, in turn, may be operatively engaged with the input gear


475


of the cam box


474


and with the input gear


514


of the cambox


512


. The second output gear


542


of the driveshaft


536


may be operatively engaged with the input gear


552


of the downstacker


550


. In this manner, the driveshaft


536


serves to drive the cambox


474


, the cambox


512


and the downstacker


550


, in a manner as previously described.




In operation of the lower assembly


414


, each forward movement of the shuttle mechanism


496


(i.e., movement in the direction


505


) serves to move a single closure member from the downstacker


550


to a position directly overlying the chuck member


482


. The chuck member


482


is then raised (via the cam box


474


as described above), causing the closure member to be loaded onto the chuck member. Thereafter, the chuck member is rotated about the axis E—E (via the servo motor


476


and gearbox


478


) and sealant is applied to the closure member by a sealant dispensing gun located in the upper assembly


416


, as will be described in further detail herein. After the closure member is loaded onto the chuck member


482


, the shuttle mechanism may move rearwardly (i.e., in the direction


504


) to secure the next uncoated closure member from the downstacker


550


. After the previous closure member has been coated and discharged from the chuck


482


, the shuttle mechanism moves the next closure member into place on the chuck, thus beginning the cycle again. Because of its cyclical nature (e.g., the starting and stopping of the shuttle


496


), the above type of operation is generally referred to in the industry as an indexing operating The apparatus illustrated in

FIG. 17

, thus, is known as an indexing machine. This is in contrast to a rotary or continuous motion machine, such as that illustrated in

FIGS. 1-9

and


12


-


14


.




It is noted that, although the indexing system


410


of

FIGS. 17 and 18

has been illustrated as a single lane system for purposes of illustration and description, the system


410


could readily be configured as a multi-lane system in which a plurality of dispensing guns are provided in side-by-side relationship.




The shuttle mechanism of a conventional indexing machine is typically driven by a crank mechanism which, in turn, is driven by the main drive unit of the machine. It has been found that the use of such a crank mechanism limits the speed at which closure members can be loaded by the shuttle mechanism onto the chuck member for coating.

FIG. 26

illustrates motion characteristics for a typical crank driven shuttle mechanism. Referring to

FIG. 26

, crank rotation (in degrees) is illustrated on the x-axis


740


. The line


750


indicates the linear displacement of the shuttle mechanism in the directions


504


,


505


,

FIG. 17

, versus crank rotation. The line


770


indicates the linear velocity of the shuttle mechanism in the directions


504


,


505


versus crank rotation.




Referring again to

FIG. 26

, at a point


752


, crank rotation is equal to zero degrees and the shuttle is in its fully retracted position. Accordingly, at this point, shuttle displacement


750


is equal to zero. At a point


754


(where the crank has rotated 180 degrees), the shuttle is at its fully extended position. It is at this shuttle position that a closure member may be loaded onto the chuck of the sealant dispensing machine. The point


754


, thus, represents the point of maximum displacement of the shuttle in the direction


504


. As the crank continues to rotate to 360 degrees, the shuttle returns to its fully retracted position


752


.




As can be appreciated, as the shuttle initially begins to move from its fully retracted position


752


, shuttle velocity


770


is very low. Shuttle velocity


770


reaches its maximum value at a point


756


where crank rotation is equal to 90 degrees. This point


756


is also the point at which the shuttle has traveled half way between its fully retracted position


752


and its fully extended position


754


. As the shuttle moves from the half way point


756


to the fully extended position


754


, shuttle velocity


770


begins to decrease, until it reaches zero at the fully extended position


754


.




As can be appreciated from the above description, and with reference to

FIG. 26

, the shuttle moves at its maximum velocity


756


for only an instant during its movement. Accordingly, the average velocity of the shuttle is relatively low. This is disadvantageous because it limits the overall speed at which closure members can be processed. The present sealant dispensing system


410


overcomes this disadvantage by driving the shuttle mechanism


496


with a cam box


512


, rather than a crank device.





FIG. 27

illustrates the movement characteristics of the shuttle mechanism


496


over


360


degrees of rotation. Specifically, the line


800


illustrates the rotation of the chuck member


482


. The line


820


illustrates the lift of the chuck


482


in the directions


466


,


468


, FIG.


17


. The line


840


illustrates the displacement of the shuttle in the directions


504


,


505


in a manner similar to the line


750


of FIG.


26


. As can be seen, with reference to the line


840


, the shuttle


496


moves forward, in the direction


504


, in a rapid manner, reaching its fully extended position


842


in just 73 degrees of rotation. Accordingly, the entire forward stroke


844


of the shuttle


496


takes much less time than in a crank driven system. After completing its forward stroke, the shuttle mechanism


496


may dwell for a period


846


in the forward position. Thereafter, the shuttle mechanism


496


may move in the opposite direction


505


for a period


848


until it reaches its fully retracted position


852


. The shuttle mechanism may then dwell in the retracted position for a period


850


. As can be appreciated, this operation of the shuttle mechanism reduces the time required to load a closure member onto the chuck member


482


and, thus, decreases the overall cycle time to process a closure member.




The advantageous operation of the shuttle mechanism described above is enabled by the use of the cam box


512


in place of a conventional crank mechanism. The particular profile of the cam contained within the cam box


512


may be chosen to create the motion profile illustrated in

FIG. 27

in a conventional manner.





FIGS. 19-22

illustrate the upper assembly


416


of the sealant dispensing system


410


in further detail. Referring to

FIGS. 19 and 20

, upper assembly


416


may include a support member


600


extending upwardly from the upper surface


413


of the support structure


412


of the lower assembly


414


. A bracket


602


may be attached to the support member


600


, as best shown in

FIG. 20. A

cradle member


604


may be supported by the bracket


602


such that the cradle member is rotatable about the axis G—G. Cradle member


604


may include an elongated hole or slot


616


, as shown. Cradle member


604


may further include a threaded hole


606


,

FIG. 19. A

sealant dispensing gun


610


may be held within the cradle member


604


via a clamp member


608


which, in turn, may be secured to the cradle member


604


via a bolt


612


,

FIG. 20

, engaged within the threaded hole


606


. The dispensing gun


610


may, for example, be substantially identical to the dispensing gun


120


previously described with respect, e.g., to

FIGS. 6 and 7

.




As can be appreciated, the dispensing gun


610


, mounted in a manner as described above, is able to pivot in the directions indicated by the arrow


614


,

FIG. 19

, about the axis G—G. As can further be appreciated, the lower portion of the dispensing gun


610


will be located adjacent the chuck


482


of the lower assembly


414


and, thus, is able to apply sealant to closure members, such as the closure member


500


illustrated in

FIGS. 19 and 20

in a manner as previously described.




Referring again to

FIGS. 19 and 20

, upper assembly


416


may further include a support and drive assembly


630


. Support and drive assembly


630


may be mounted to the support member


600


in a manner as will be described in further detail herein. Generally, the support and drive assembly


630


includes a roller


694


which is forced to move in the linear directions indicated by the arrows


632


,


634


, FIG.


19


. The roller


694


, in turn, is captured within the slot


616


of the cradle member


604


. As can be appreciated, movement of the roller


694


in the direction


632


will cause the lower portion of the dispensing gun


610


to pivot in a counter-clockwise direction about the axis G—G. Conversely, movement of the roller


632


in the direction


634


will cause the lower portion of the dispensing gun


610


to pivot in a clockwise direction about the axis G—G.




With reference again to

FIGS. 19-22

, the configuration and operation of the support and drive assembly


630


will now be described in further detail. Support and drive assembly


630


may include an L-shaped support


636


,

FIGS. 20 and 21

, which may be attached to the support member


600


via a plurality of bolts, such as the bolt


638


, FIG.


20


. Referring to

FIG. 21

, a guide rail


642


may be attached to the L-shaped support


636


as shown. A slide member


644


may be slidingly attached to the guide rail


642


such that the slide member


644


, and components attached thereto, are moveable relative to the L-shaped support


636


in the directions indicated by the arrows


632


,


634


, FIG.


19


. The guide rail


642


and slide member


644


, together, may constitute a support mechanism


640


. Support mechanism


640


may, for example, be a conventional slide support mechanism, such as the type commercially available from THK America Inc. of Cypress, Calif. and sold as Model SSR-15W.




Referring again to

FIG. 21

, a rear L-shaped bracket


650


may be attached to the support mechanism slide member


644


as shown. A first top bracket


654


, in turn, may be attached to the rear L-shaped bracket


650


. A block


658


may be attached to the first top bracket


654


and may be further attached to an armature portion


662


of a drive mechanism


660


. A sensor bracket


670


may also be attached to the block


658


as shown. Sensor bracket


670


may include a linear encoder tape scale


672


.




With further reference to

FIG. 21

, a front bracket


676


may be attached to the L-shaped support


636


. An L-shaped bracket


678


, in turn, may be attached to the front bracket


676


. A support plate


680


may be attached to the L-shaped bracket


678


and may, in turn, support a sensor mechanism


674


as shown. Sensor mechanism


674


and tape scale


672


, together, comprise a sensor assembly


668


. In operation, the sensor mechanism


674


determines the position of the moveable sensor bracket


670


relative to the stationary sensor mechanism


674


. Sensor assembly


668


may, for example, be a conventional sensor assembly, such as the type commercially available from Anorad Corporation of Hauppauge, N.Y. and sold as Model MERS50-D1.




A U-shaped member


664


may be attached to the L-shaped support


636


and located between the L-shaped support


636


and the front bracket


676


as shown. A pair of stator members


665


,


666


may be supported by the U-shaped member


664


. U-shaped member


664


, stator members


665


and


666


, armature portion


662


and block


658


, together, may comprise a drive mechanism


660


. Drive mechanism


660


may be a conventional electromagnetic linear actuator in which the armature portion


662


(along with the components attached thereto) may be driven in the directions


632


,


634


,

FIG. 19

, via interaction between the stationary stator members


665


,


666


and the moveable armature portion


662


. Drive mechanism


660


may, for example, be of the type commercially available from Anorad Corporation of Hauppauge, N.Y. and sold as Model LEM-S-3-S-NC-TE-HET. Alternatively, drive mechanism


660


may be configured as any other type of linear actuator, such as pneumatic or hydraulic actuator.




Referring to

FIGS. 19 and 20

, a second top bracket


690


may be attached to the L-shaped rear bracket


650


and to the block


658


, as shown. A bracket


692


, in turn, may be mounted to the second top bracket


690


. Bracket


692


may support the roller


694


, as previously described, for rotation about the axis H—H.




As can be appreciated, activation of the drive mechanism


660


will cause the armature portion


662


and attached rear L-shaped bracket


650


to be selectively moved in the directions


632


and


634


, FIG.


19


. This movement will also cause the roller


694


, which is ultimately attached to the rear L-shaped bracket


650


, to move in the directions


632


,


634


. This movement of the roller


694


, in turn, will cause the dispensing gun


610


to pivot in the directions indicated by the arrow


614


,

FIG. 19

, in a manner as previously described. The sensor assembly


668


serves to detect the relative position of the sensor bracket


670


and, thus, is able to determine the relative position of the roller


694


and, accordingly, the direction and degree of pivoting of the dispensing gun


614


. The sensor assembly


668


, the drive mechanism


660


, the dispensing gun


610


and the servo motor


476


may all be connected to a controller device, not shown, in a conventional manner in order to control and coordinate the movement of all of the components. A sensor, not shown, may also be connected to the controller device in a conventional manner in order to sense when the chuck


482


is in its raised position.




In operation, the dispensing gun


610


pivots as the chuck


482


rotates. Accordingly, the dispensing gun


610


may apply sealant to non-circular closure members in a manner similar to that described previously with respect to the pivoting dispensing gun


120


, e.g.,

FIGS. 6 and 7

. The dispensing gun


120


, however, is pivoted by a rotary servo motor


230


and gearbox


232


. The use of such a rotary servo motor and gearbox arrangement has been found to be disadvantageous in some circumstances. Specifically, it has been found that, in some circumstances, the tolerances and flexure inherent in the gears and other moving parts of the gearbox can make reliable high-speed operation problematic. The use of a linear actuator to pivot a dispensing gun, as described with respect to

FIGS. 19-22

, overcomes these potential problems associated with rotary servo motors and gears.




It is noted that the pivoting dispensing gun/linear actuator arrangement of

FIGS. 19-22

has been described in conjunction with an indexing type sealant dispensing system (i.e., the system


410


,

FIG. 17

) for illustration purposes only. In use, the pivoting dispensing gun/linear actuator arrangement could readily, instead, be used in conjunction with a rotary sealant dispensing system, such as the rotary systems described herein with respect to

FIGS. 1-9

or

FIGS. 12-14

.





FIGS. 23-25

illustrate an alternative embodiment of the upper assembly


416


. The embodiment of

FIGS. 23-25

may be substantially similar to the pivoting dispensing gun/linear actuator described above with reference to

FIGS. 19-22

. Accordingly, like elements in

FIGS. 23-25

are afforded the same reference numerals as used in

FIGS. 19-22

. In the embodiment of

FIGS. 23 -25

, however, the dispensing gun


610


does not pivot. Instead, the gun


610


is rigidly attached to the support and drive assembly


630


. Accordingly, the dispensing gun


610


moves only in a linear fashion, i.e., in the directions indicated by the arrows


632


,


634


, FIG.


23


.




As can be appreciated, with reference to

FIG. 24

, the support and drive assembly


630


may be substantially identical to that previously described with respect to

FIGS. 19-22

except that the entire assembly


630


is mounted in the opposite orientation. In other words, the support mechanism


640


, in the embodiment of

FIGS. 23-25

, is located closer to the dispensing gun


610


, while the drive mechanism


660


is located further away. This orientation of the support and drive assembly


630


allows a bracket


700


to be attached directly to the L-shaped bracket


650


. The dispensing gun


610


, in turn, may be attached to the bracket


700


. Specifically, the dispensing gun


610


may be attached to the bracket


700


in a similar manner to that described with respect to the attachment of the dispensing gun to the cradle


604


in

FIGS. 19-22

. It is noted that, to facilitate this alternate mounting arrangement of the dispensing gun


610


, the height “i”,

FIG. 23

, of the support member


600


may be reduced relative to the height of the support member in the embodiment of

FIGS. 19-22

.




As can be appreciated, in the embodiment of

FIGS. 23-25

, the upper assembly


416


may function in a similar manner to that described with respect to

FIGS. 19-22

. In the embodiment of

FIGS. 23-25

, however, the dispensing gun


610


will move only in a linear fashion, i.e., in the directions


632


,


634


, FIG.


23


.




In a similar manner to the embodiment of

FIGS. 15 and 16

, as previously described, the linear motion dispensing gun of

FIGS. 23-25

is advantageous in that the dispensing gun opening does not move in an arcuate fashion and, thus, the dispensing angle of the gun remains constant relative to the closure member. The embodiment of

FIGS. 23-25

is further advantageous relative to the embodiment of

FIGS. 15 and 16

, however, in that the embodiment of

FIGS. 23-25

reduces the undesirable play and flexure characteristics of a gear and belt driven system, such as that described with respect to

FIGS. 15 and 16

.




It is noted that the linear motion dispensing gun/linear actuator arrangement of

FIGS. 23-25

has been described in conjunction with an indexing type sealant dispensing system (i.e., the system


410


,

FIG. 18

) for illustration purposes only. In use, the linear motion dispensing gun/linear actuator arrangement could readily, instead, be used in conjunction with a rotary sealant dispensing system, such as the rotary systems described herein with respect to

FIGS. 1-9

or

FIGS. 12-14

.




It is noted that the indexing system


410


of

FIGS. 17 and 18

has been described in conjunction with particular configurations for the upper assembly


416


(i.e., the configuration of

FIGS. 19-22

and the configuration of

FIGS. 23-25

) for exemplary purposes only. The indexing system could, alternatively, be configured having any type of upper assembly


416


, such as a pivoting dispensing gun/rotary actuator (e.g.,

FIGS. 1

,


2


,


4


,


6


,


7


and


12


) or a linear motion dispensing gun/rotary actuator (e.g, FIGS.


15


and


16


).




While an illustrative and presently preferred embodiment of the invention has been described in detail herein, it is to be understood that the inventive concepts may be otherwise variously embodied and employed and that the appended claims are intended to be construed to include such variations except insofar as limited by the prior art.



Claims
  • 1. A method of applying a fluid to a member, comprising:providing a fluid dispensing mechanism comprising an opening therein; dispensing said fluid from said opening in said fluid dispensing mechanism onto said member in a non-circular preprogrammed pattern by: a controlled rotating of said member about a rotation axis; and a controlled pivoting of said dispensing mechanism about a pivot axis; and wherein said member is a container closure member.
  • 2. The method of claim 1 wherein said fluid is a sealant.
  • 3. The method of claim 1 wherein said pivot axis is substantially perpendicular to said rotation axis.
  • 4. The method of claim 1 wherein said container closure member is non-circular.
  • 5. The method of claim 1 and further comprising:providing a rotatable support for supporting said member; moving said member onto said rotatable support, wherein said rotating said member further comprises rotating said rotatable support; and stopping rotation of said rotatable support before said member is moved onto said rotatable support.
  • 6. The method of claim 1 wherein said rotating said member comprises loading said member onto a rotatable support which is operatively attached to a servo motor and further comprising:rotating said rotatable support with said servo motor.
  • 7. The method of claim 1 wherein said pivoting comprises activating a servo motor operatively attached to said fluid dispensing mechanism.
  • 8. The method of claim 1 wherein said pivoting comprises activating a linear actuator operatively attached to said fluid dispensing mechanism.
Parent Case Info

This application claims the benefit of U.S. Provisional Application No. 60/110,036, filed Nov. 25, 1998, and U.S. Provisional Application No. 60/146,555, filed Jul. 30, 1999, both of which are hereby incorporated by reference for all that is disclosed therein.

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Non-Patent Literature Citations (1)
Entry
Alfons Haar Brochure, “Unround shape, single nozzle end lining maching”, date unknown, 1 page (no date).
Provisional Applications (2)
Number Date Country
60/110036 Nov 1998 US
60/146555 Jul 1999 US