US3010351A - Scoop removal and dispensing machine - Google Patents

Description

NOV. 28, 1961 FlRlNG SCOOP REMOVAL AND DISPENSING MACHINE 5 Sheets-Sheet 1 Filed Dec. 6, 1

INVENTOR llll llmlnlllllllhl llullnnumm l Osborne Firing BY ORNEY Nov. 28, 1961 o. FIRING SCOOP REMOVAL AND DISPENSING MACHINE 5 Sheets-Sheet 2 Filed Dec. 6, 1957 INVENTOR Osborne Firms ORNEY Nov. 28, 1961 o. FIRING SCOOP REMOVAL AND DISPENSING MACHINE 3 Sheets-Sheet 3 Filed D80. 6, 1957 INVENTOR Osbarne Firi BY A ORNEY Patented Nov. 28, 1961 3,010,351 SCOOP REMOVAL AND DISPENSING MACHINE Osborne Firing, Woodbury, Conn., assignmto Scovill Manufacturing Company, Waterbury, Conn., a corporation of Connecticut Filed Dec. 6, 1957, Ser. No. 701,175 4 Claims. (Ci. 83255) This invention relates to what has been called zipper dispensing machines. Such a machine is useful to a large volume manufacturer of garments who may purchase long lengths of continuous zipper chain and cut them up to him own requirements as to lengths and as to tape extensions which are free of metal fastener elements.

Although such a machine, broadly speaking, is not a new proposal, it presents such problems that those machines which heretofore have been designed for this purpose are complicated and expensive, relatively slow in operation and unreliable in use.

The object of my invention, therefore, is to provide a zipper dispensing machine involving a departure in the principles of operation so that it is simple in construc tion and can be operated at higher speeds. My improved machine results in a construction which has a minimum number of complications and in which the various essential parts are readily accessible. In this machine there is combined the principle of continuous feed rollers for the material with a clamping device which intermittently stops the movement of the zipper chain during operation of the fastener element removal tools and also of the severing tools which cut through the tape at a blank portion to sever the chain into individual fastener lengths. Upon release of the clamping device after operation of the element removal and severing tools, the continuously operated feed rollers again advance the chain. The clamping device is operated by cams on the same power shaft which operates directly the fastener element removal tools and shearing tools so that for each revolution of the shaft, a fastener length is produced and severed from the chain and these cams are adjustable to time the clamping device so as to stop the feed of the chain after it has advanced enough for the desired fastener length.

Another feature of my invention in this combination is that the feed rollers and the severing tools are mounted on a common carriage which is adjustable lengthwise along the power shaft to a position dependent on the length of the zipper to be made so that the shearing tools will operate at the desired place in the gap previously produced by the element removal tools.

While my machine has means to feed a measured length which is an improvement over prior machines, it also incorporates an improved device for giving a fine adjustment to the chain before operation of the element removal tools so as to register the same accurately with respect to those tools.

Other objects and advantages of my invention will hereinafter more fully appear. In the accompanying drawing, there is shown for the purpose of illustration, one embodiment which my invention may assume in practice.

In the drawings:

FIG. 1 is a front elevational view of my improved machine for removing fastener elements from a zipper chain with portions of the machine broken away to show the interior construction.

FIG. 2 is a left end view of the clamping device of this machine showing the device in clamped position.

FIG. 3 is a view similar to FIG. 2 showing the device in released position.

FIG. 4 is a partial elevation and section of the cam unit on the main shaft for operating the clamping device.

FIG. 5 is a right end view of the movable carriage in which are mounted the feed rollers and shearing tools with the cover plate removed.

FIG. 6 is a horizontal cross-sectional view of the movable carriage taken along the line 66 of FIG. 5.

FIG. 7 is an enlarged side view of the ratchet dog member forming a part of the element-removal tools.

FIG. 8 is a cross-sectional view of the same taken along the line 8-8 of FIG. 7.

FIG. 9 is a diagrammatic view of several parts of the machine units shown in relation to the zipper chain.

FIG. 10 is a right side view of the upper end of the element-removal tools with portion broken away.

The machine is adapted to operate upon a long length of continuous zipper chain, a piece of which, best shown in FIG. 9, is designated by the letter C. The chain C consists essentially of two parallel fabric tapes T having the usual beaded edges to which are secured the conventional separable fastener elements E interfitted with each other in staggered relationship.

The machine illustrated consists generally of a support table or frame 10 upon which is supported a pair of spaced standards 11 and 12 respectively designated left and right standards. These standards support a main drive shaft 13 and a tie rod 14. FIG. 1 from left to right, the respective units are a pay-01f reel 15, a chain clamping device 16, an element removal tool 17 and a movable carriage 18 which supports the feed rollers and shearing tools. The main drive shaft 13 is powered by a constant speed electric motor 19 through pulleys 20 and 21 and belt 22.

The pay-off reel 15 employs a drum 23 consisting of a hub 23a mounted to rotate freely upon the shaft 13 and end flanges 24 and 25. The right flange 25 is made secure to one end of the hub 23a while the left flange 24 is removable therefrom. For this purpose, the flange 24 is abutted against the outer face of the hub 23a and held thereagainst by a spring 26 compressed between said flange and a thrust bearing 27 backed up by the flanged end of a sleeve 28 slidable on shaft 13. A hand wheel 29 is attached to the outer end of the sleeve 28 and together have a bayonet lock connection 30 with the outer end of the shaft 13. The spring 26, bearing 27 and flanged end of sleeve 28 are housed with a protective cap 31. By turning the hand wheel 29 relative to its bayonet lock connection 30 with the shaft 13, the wheel 29, sleeve 28, bearing 27, spring 26 and reel flange 24 may be removed as a unit to permit an exhausted chaincontainer spool S to be removed from the hub 23a and a loaded spool replaced thereupon. The hub 23a and flange 25 are retained upon the shaft 13 during the interchange of spools by a collar 32 secured to said shaft and received in a suitable recess 23b in the adjacent end of hub 23a.

The reel 23 is adapted to be driven by a clutch plate 33 carried by the drive shaft 13 and abutted against the right reel flange 25. The flange 25 is held in frictional drive engagement with the clutch plate 33 by the compression spring 27 described above in connection with the removable flange 24 and normally urging the reel 23 to the right as seen in FIG. 1.

When the machine is not demanding any zipper chain from the pay-otf reel 15, it is necessary to stop the rotation of the drum 23 by disengaging it from the constantly driven clutch plate 33. For this purpose, a brake-andclutch release device is provided which consists specifically of a pair of brake shoes 35 pivotally carried by the yoke portion 36a of a lever 36 and normally bearing against the right reel flange 25, one on each side of said clutch plate 33. The upper end of the lever 36 is pivotally attached to the left end of the tie rod 14 as at 37 while its lower end is pivotally connected to a long rod 38, in turn connected to the intermediate portion of a short arm 39a of a bell crank lever 39 pivoted on a cross shaft 40 suitably mounted in the machine frame 10. The upper end of the arm 39a is tensioned to the right as by means of a light spring 41 and a turn-buckle 42 attached to the frame 10. The bell crank lever 39 has a long arm 39b that extends through a suitable opening in the left wall of the machine frame 16 and terminates with an eye 43 located directly below the drum 23 and through which the zipper chain C from the spool S is threaded and thence is directed upwardly to a pair of guide rollers 44 and 45 suitably supported above the machine. As will be more fully explained later, any slight pull upwardly on the eye 43 on the end of the long arm 3% by a tug on the chain C will cause the brake shoes 35 to be released from the spool flange 25 and permit the spool to be rotated by the clutch plate 33 connected to the drive shaft 13.

Chain clamping device The chain clamping device 16 (see FIGS. 2 and 3) consists of a bracket 46 pivoted at an intermediate portion on a stud shaft 47 supported by a pair of lugs 48 projecting from the left side of the standard 11 as viewed in FIG. 1. The upper end of the bracket 46 carries an integral plate 49 which supports a chain-engaging lower friction block 50. To one side of the plate 49 is pivoted a swinging arm 51 extending above and across the bracket plate 49 and to which is pivotally mounted a plate 52 complemental to the plate 49 and which in turn carries an upper friction block 53. The blocks 50 and 53 are adapted to grip opposite sides of zipper chain C and each block is provided with a longitudinal channel 50a and 53a on their adjacent faces for clearing the fastener elements E carried by the chain C.

The upper friction block 53 is normally urged downwardly against the lower friction block 50 to frictionally grip the chain C by a coil spring 54 tensioned between the pivot plate 52 and a pin connection 55 with the bracket 46 (see FIGS. 1 and 9). These friction blocks 50 and 53 thus normally serve as a chain tensioning device, when the chain is pulled through said blocks by the feed rollers 106 (later described in connection with carriage 18) when the plates 49 and 52 are in their unclamped position. The zipper chain C is guided into the friction blocks 50 and 53 from the upper guide roller 45 through an eye loop 56 and a guide roller 57 carried by an angle arm 58 integral with the bracket plate 49.

When the chain clamping device 16 is operated to clamp the chain C to arrest the movement of same against the pulling force of the feed rollers 106, it is necessary to firmly hold the friction blocks 50 and 53 against opposite sides of the chain tapes T. For this purpose, a latch piece 59 is secured to the free end of the arm 51 which piece cooperates with a catch 60 carried at the upper end of the long arm 61a of a bell crank lever 61. The catch 60 is engaged against the upper surface and urged downwardly against the latch piece 59 when it is desired to have the blocks 50 and 53 clamped against opposite sides of the chain tapes T with a sufiicient grip to overcome the pulling force of the feed rollers 106. To obtain the necessary required downward force for the catch 60 against latch piece 59, the bell crank lever 61 is pivoted at 62 to the free end of a swinging arm 63 in turn pivoted at 64 to the bracket 46 (see FIGS. 2 and 3). The bell crank lever 61 and the swinging arm 63 as a unit are normally urged downwardly pivoting clockwise on pivot 64 by a coil tension spring 65 having one end anchored to the frame and'its opposite end to a pin 66 located at an intermediate point on the short arm 61b of the lever 61. At the same time that the lever 61 and the arm 63 are pivoting clockwise about the pivot 64, said lever 61 is urged in a counter-clockwise direction as seen in FIG. 2 about the pin 62 to assure that the catch 60 will be retained in latched engagement with latch piece 59.

When it is desired to release-the catch 69 from the latch piece 59, a release cam 67 keyed to the main drive shaft 13 is provided with a projection 67a that contacts a roller 68 carried on the free end of the short arm 61b of the bell crank lever 61 and swings said lever 61 clockwise about its pivot 62 and consequently releases the catch 60 from the latch piece 59, allowing the bell crank and swinging arm unit to drop to the position shown in FIG. 3. This, of course, releases the clamping effect of the friction blocks 50 and 53 upon the chain tapes T and allows the chain to be pulled through said blocks under some degree of tension such as supplied by the spring 54. The downward movement of the bell crank lever 61 and the swinging arm 63 as a unit is limited by a control rod 69 anchored at its lower end to the pin 69a on swinging arm 63 and having its upper end extending through a stop lug 70 projecting from bracket 46 and carrying a pair of adjusting nuts 71 and a buffer block 72, such as rubber, interposed between said nuts 71 and stop lug 70.

The cam unit on shaft 13 for operating the bell crank 61 and swinging arm 63 as a unit, as best shown in FIG. 4, will now be described. A reset cam 73 is furnished with a relatively long hub 73b by means of which said cam is mounted on shaft 13 and keyed thereto as by a spline 73e. When it is desired to release the catch 60 with respect to the latch piece 59, the release cam 67 is rotatably mounted on the cam hub 73b and is secured to a dial plate 74 as by screws 74a. A friction plate 75 abuts the opposite face of the dial plate 74 and is keyed to the cam hub 73b at 75a. The friction plate 75 is forced against the dial plate 74 by a capstan nut 76 threaded upon hub 73b and consequently urges the cam 67 and dial plate 74 against the abutment shoulder 730 on hub 73b so that all parts mounted on the cam hub 73b are carried as a unit with the reset cam 73 when the capstan nut 76 is tightened up. The reset cam 73 is provided with. a projection 73a that contacts a roller 77, carried at an intermediate portion of the swinging arm 63 and forces the latter with its bell crank lever 61 as a unit upwardly from the position of FIG. 3 to the position of FIG. 2. The catch 60 is formed with an inclined cam face 60a that permits said catch to glide upwardly past the end of the latchblock 59 and catch thereover during the resetting operation under the influence of spring 65.

The release cam 67 and the reset cam 73 are mounted as described above so that upon a slight loosening of the capstan nut 76, the release cam 67 may be adjusted to a different position relative to the reset cam 73 as determined by the length of the stringer to be cut by the machine. For this purpose, the dial plate 74 is provided with suitable indicia 74b on its circumference that can be set with respect to an index mark 75b on the periphery of the friction plate 75, which setting must be coordinated with corresponding indicia 14a on the tie rod 14 as will be fully explained later in connection with the movable carriage 18.

Element removal unit The element removal unit 17 is associated with the left standard 11 on which is mounted a housing 80 having fixed therein a die 81 and an element-cutting blade 82 reciprocally mounted therein (see FIGS. 1 and 10). The blade 82 is suitably attached to a yoke unit which comprises an upper yoke 83 located above the housing 80, a pair of tie rods 84 and a lower yoke 85 attached to the lower ends of said rods and positioned within the standard 11. The rods 84 are slidably mounted in suitable bearings 84a in the standard 11 (see FIG. 1). The lower yoke 85 supports a roller 86 engaged against a cam 87 keyed to shaft 13. The yoke unit is normally urged upwardly by a pair of compression springs 88 surrounding buffer pins 89, the latter having suitable heads 89a resting against the top surface of the housing 80. The cam 87 operates to move the yoke unit downwardly against the influence of springs 88 and cause the blade 82 to shear 011 a predetermined number of elements E from chain C.

In order to assure that the elements E to be cut and removed from the chain tapes T are located in proper relationship with respect to the shear blade 82 so as to avoid cutting through only a portion of the elements, means are provided for accurately adjusting the chain with respect to the element removal tools just prior to the operation of such tools. For this purpose, a pair of ratchet dogs 90 are mounted on the lower end of an L- shaped carrier 91 slidably held against one side of the housing 80 by a cover plate 92. As best seen in FIG. 8, each dog 90 has a pair of teeth, and the dogs 90 are riveted in the carrier 91 so that their teeth will be in staggered relationship in conformity with the elements on the chain C. The carrier 91 is urged downwardly by a coil spring 93 positioned in a slot 91a in carrier 91 and having its upper end abutted against a stop pin 94 in housing 80. This construction permits the elements on the chain C to ratchet past the teeth on the dogs 90 as the chain passes to the right through the machine. The teeth on the dogs 90 are also adapted to catch in back of the elements on the chain that are disposed directly therebelow when the chain is arrested in ts travel through the machine and given a tug to the left by a swinging movement of the bracket 46 in a counter-clockwise direction about the stud shaft 47. To allow the above motion, the lower end of the bracket 46 supports a roller 95 controlled by the side face of a cam 96 on the drive shaft 13. The bracket 46 is normally urged to swing counter-clockwise about shaft 47 by a coil spring 97 located above said shaft and compressed between the bracket 46 and the adjacent face of the standard 11 (see FIGS. 1 and 9). The chain clamp ing tools on the upper end of bracket 46 are held against movement or in a state of rest in spite of the influence of the spring '97 by reason of the roller 95 hearing against the side face of the cam 96, until the roller 95 engages in a recess 96a in the cam face thereby causing clamping tools to move to the left. This movement of the tools by reason of the counter-clockwise motion of the bracket 46 assures that the elements on the tape T will be properly located below the blade 82 to avoid shearing through only a portion of an element.

The elements which are cut off the chain C by the die 81 and blade 82, which for the most part will be the heads of the elements, will drop by gravity through the opening in the die 81 into a chute 98 in standard 11 and directed outwardly thereof where they can drop by gravity into another chute 99 supported in the frame from which chute they are directed into a suitable scrap container. The legs of the elements that may be carried beyond the element-removal unit 17 and particularly those that are disposed on the upper side of the chain, may be removed by a suction head 100 and carried through a conduit 101 to a motorized suction unit 102 which will force them into the chute 99.

Movable carriage with feed rollers and shearing tools The movable carriage unit 18 comprises a housing 103 that is supported by the drive shaft 13 and tie rod 14 and movable to different positions therealong. Before the chain C is drawn into the unit 18, a star wheel 104 is mounted on a bracket 105 projecting from the housing 103 and is adapted to be operated by the passage of the chain thereover. The rotation of the star wheel 104 by the passage of the chain serves to vibrate said chain for the purpose of knocking off any of the cut elements that may perchance adhere to the lower surface of said chain.

In order to draw the chain C through the machine, two sets or pairs of power-driven feed rollers 106 and 107 are positioned to the front of the upper'portion of the housing 103 and are adapted to frictionally grip opposite sides of the chain tapes T therebetween. The first pair of rollers 106 in the carriage 18' on the entrance side of shearing tools 121 and 122' and the second pair of rollers 107 are mounted in said carriage on the other side of said shearing tools. The upper rollers of the sets 106 and 107, as best seen in FIG. 6 are carried by shafts 108 and 109 mounted on bearings 110 and 111 in housing 103. The shafts 108 and 109 are driven by helical gears 112 and 113 meshing with similar helical gears 114 and 115 on a drive shaft 116 having bearing mounts 117 in housing 103. The shaft 116 has a sprocket 118 on one end driven by chain 119 from a larger sprocket wheel 120 keyed to power shaft 13 (see FIG. 5). It will be understood that the lower rollers of the sets 106 and 107 are driven the same as the upper rollers through helical gears (not shown) meshing with the helical gears 114 and 115 on the drive shaft 116. This chain drive steps up the speed of the rollers as compared to the drive shaft 13 so that the rollers Will turn sufliciently for each revolution of said drive shaft to advance the tapes a distance equal to the maximum length of fastener length to be made.

The means for cutting the chain C to a predetermined length is best shown in FIGS. 1 and 5 and consist of a stationary anvil blade 121 and a movable cutting blade 122 which are located between the two sets of rollers 106 and 107 as explained above. The anvil blade 121 is made secure to an overhanging block 123- attached to the upper surface of the housing 103. The cutting blade 122 is carried by a reciprocating plunger 124 in housing 103 and derives its motion from a roller 125 engaging a cam wheel 126 keyed to power shaft 13. The roller 125 is connected to the plunger 124 by a shaft pin 127 having its end extending outwardly of said plunger, which ends are engaged by springs 128 and normally urge the roller 125 downwardly against the face of the cam wheel 126. The cam wheel 126 is formed with stepped hubs 129 on opposite sides thereof for engagement in bearings 130 mounted in housing 103. Projecting from the cam wheel 126 is a projection 126a that is adapted to contact the roller 125 once every revolution of the shaft 13 for the purpose of elevating the plunger 124 and cutting a measured length from the advanced end of the chain C to provide a stringer with element-free ends, such as shown at C1 in FIG. 9. The movable carriage unit 18 is supported in part upon the drive shaft 13 by hearing 130 and in part by the tie rod 14. The cam wheel 126 and sprocket wheel 124 have slidably keyed connections along the major length of drive shaft 13.

In order to move the carriage unit 18 to different adjusted positions relative to the machine frame 10, a screw shaft 131 is provided having its opposite ends rotatably mounted in the standads 1-1 and 12. The screw shaft 131 may be operated by hand wheel 132 attached to the right end thereof as viewed in FIG. 1. A suitable screw connection may be had with some portion of the housing 103 of the carriage unit 18 for the purpose of moving it to any adjusted position between the standard 12 and the chain clamping device 16. A suitable index finger 133 is carried by housing 103 that may be indexed with the indicia 14a on the tie rod 14 for obtaining the proper setting of the unit in accordance with the desired length of stringer tapes to be cut from the Zipper chain C.

Operation When the desired length of chain with element-free extension is determined, it is first necessary to adjust the carriage unit 18 along the power shaft 13 to a position where the index finger 133 on the housing 103 registers with the indicia 14a on rod 14 designating the length of chain to be cut. Also, it is necessary to adjust the release cam 67 by turning the dial plate 74 so that the indicia on said dial plate corresponding with like indicia on rod 14 will register with the index mark 75b on friction plate 75. After the chain spool S carrying the Continuous chain C is assembled to the pay-off reel 15, the chain C may be threaded through the various guide eyes, over the guide rollers and through the various operating units in the manner as clearly shown in FIG. 1 and then the machine is ready for operation.

As soon as the feed rollers 106 and 107 start drawing the chain C and slipping it through the clamping device 16, a slight upward tug on the chain that passes from the spool '8 through the eye 43 will cause the arm 3% of hell crank 39 to swing upwardly and release the brakes 35 from the drum flange 25 and cause the clutch 33 to operate the pay-off reel 15. Thus it will be understood that the drum 23 is power-driven during the time the feed rollers are drawing the chain through the machine. When the required length of chain has passed through the carriage unit 18, the reset cam 73 will raise the swinging arm 63 and bell crank 61 as a unit and cause the catch 60 to engage over the latch piece 59 which consequently will cause the friction blocks 50 and 53 to grip the chain C sufficiently to overcome the pulling force of the feed rollers 106 and 107 and thus arrest the movement of the chain through the machine. As soon as the movement of the chain is arrested, the eye 43 on the end of the bell crank 39 will drop because of slack in the chain causing the brakes 35 to re-engage the drum flange 25, stop its rotation and move it away I from the drive clutch 33, thus preventing any over-run ning of the pay-oil reel 15. With the movement of the chain arrested, the teeth on the ratchet dogs 90 will be interengaged with the elements E on the chain C after which the bracket 46 will next be given a slight counterclockwise movement about its pivot 47 by the joint action of cam 96 and spring 97 and causing the clamping tools carried by said bracket 46 to move slightly to the left thus assuring that the elements on the chain are in proper relationship to the cutting blade 82 in the elementrem-o-val unit 17.

Next, the element-removal unit 17 will operate to cut off several elements from the chain to provide the required element-free space on the chain and at a slightly different time the cutting blade 122 in the carriage unit 18 will operate to transversely cut the chain intermediate an element-free space that was produced during the previous cycle of operations. By designing the earns 87 and 126 on the drive shaft 13 so that the cut-off tools operate ahead of, or later than, the element-removal tools, excessive stresses on the shaft 13 and other parts of the machine are avoided. As soon as the chain severing operation has taken place, the severed length of chain will be ejected from the carriage unit by the second set or discharge rollers 107 and dropped into a suitable container, thus completing one cycle of operations, after which the release cam 67 will operate to release the clamping blocks 50 and 53 and another length of chain will be advanced through the machine.

While I have shown and described in this application one embodiment which my invention may assume in practice, it is to be understood that this embodiment is merely for the purpose of illustration and that various other forms may be devised within the scope of the invention.

What I claim is:

1. A zipper dispensing machine comprising fastener element removal tools, a main shaft carrying a cam for operating said tools upon each revolution of the shaft,

8 a carriage adjustable along the shaft and supporting feed rollers adapted to frictionally grip the zipper chain and also shearing tools to sever a fastener length from the end of the chain, a cam mounted in said carriage and slidably keyed to said shaft for operating said shearing tools upon each revolution of said shaft, said carriage being located forwardly of said element removal tools with reference to the direction of movement of the chain, a chain clamping'dev ice adjacent to and on the side of said fastener element removal tools opposite from the feed rollers, cam means on said shaft to operate said clamping device to clamp the zipper chain and hold it stationary during operation of the element removal tools and shearing tools, and means for continuously operating said feed rollers to intermittently advance the chain upon release of said clamping tools.

2. A zipper dispensing machine comprising a frame, a main shaft journalled in said frame, a fastener element removal unit attached to the frame and fixed against movement lengthwise of the shaft, fastener element removal tools in said unit for removing at least one group of fastener elements to provide a gap between groups of elements, a tie rod attached to the frame parallel to said shaft, a carriage mounted on said tie rod and shaft and adjustable in a direction parallel to said shaft, -a pair of feed rollers mounted in said carriage adapted to frictionally grip the zipper chain, means for continuously operating said feed rollers, shearing tools also mounted in said carriage to sever a fastener length from the end of the chaimsaid carriage being located forwardly of said element removal tools with reference to the direction of movement of the chain, cam means on said shaft for operating the element removal tools and other cam means slidably keyed to said shaft for operating said shearing tools, a chain clamping device attached to the frame on the side of the element removal tools opposite the feed rollers, cam means on said shaft to operate said clamping device to clamp the zipper chain and hold it stationary during operation of the element removal tools and shearing tools, and means for adjusting said clamp operating cam means to vary the fraction of the cycle during which the chain is clamped.

3. A zipper dispensing machine as defined in claim 2 wherein said clamping device includes a pair of friction blocks beaning on opposite sides of said chain, spring means normally pressing said blocks toward each other to place tension of the chain during movement thereof by said feed rollers, and cam operated means controlling said clam-ping device to apply greater pressure to said blocks to hold the chain stationary against the frictional pull of said feed rollers.

4. A zipper dispensing machine as defined in claim 2 having in combination therewith means for accurately adjusting the chain with respect to the element-removal tools just prior to operation of such tools, comprising a spring-held ratchet dog bearing against the fastener elements between the removal tools and the feed rollers, and means for moving said clamping device while it is clamping the zipper chain to move the chain backwardly and tighten the chainagainst said ratchet dog.

References Cited in the file of this patent UNITED STATES PATENTS 43,458 Moseley July 5, 1864 341,700 Stimson May 11, 1886 823,269 Feinblatt June 12, 1906 930,433 Stover Aug. 10, 1909 2,369,617 Somerville Feb. 13, 1945 2,519,669 Krag Aug. 22, 1950 2,572,137 Grieder Oct. 23, 1951 2,752,997 Soave July 3, 1956 2,798,549 Feitl July 9, 1957

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