GB2187230A - Pull tab applicator for a machine for automatically assembling slide fastener sliders - Google Patents

Abstract

A pull tab applicator applies a pull tab (17) to a slider body (11) in a machine for assembling a slide fastener slider. A pair of grippers (27, 28) is movable relatively away from and toward each other and disposed to confront the face and back, respectively, of a supplied pull tab.The grippers (27, 28) have confronting surfaces (29, 30), respectively, at least one of the confronting surfaces (29, 30) having a slot (33) for receiving the pull tab therein. The slot (33) is inclined in a direction to bring down the pull tab as applied to the slider body (1 1). A driver is coupled to at least one of the grippers (27, 28) for moving said one gripper (28) between a first position close to the other gripper (27) to grip the pull tab in the slot (33) therebetween and a second position remote from the other gripper (27) to allow the pull tab to be brought down in an orderly manner. <IMAGE>

Description

SPECIFICATION Pull tab applicatorfora machine for automatically assembling slide fastener sliders Description: The present invention relates to a pull tab applicator for automatically applying pull tabs successively to slider bodies in an automatic assembling machine for successively assembling sliders for slide fasteners.

Japanese Patent Publication No. 57-41244 pub lishedonSeptember2, 1982 discloses a pull tab applicator for use with an assembling machine which assembles slide fastener sliders. The disclosed pull tab applicator has a hasa pairofgrippersforgrippingthe opposite side edges of a pull tab supplied onto a slider body in the assembling machine. Whilethegrippers are moving in a direction to bring down the pull tab, they are cammed apartfrom each other out of gripping engagement with the pull tab.

One problem with the prior pull tab applicator is as follows: During the spreading movementofthe grippers, the pull tab is liable to be tilted laterally toward one of the g rippers. This tendency of the pull tab is particularly strong where the pull tab is larger in its upper portion than in its lower portion, i.e. it has a high center ofgravity in its vertical position. The pull tab as it is applied to the slider body is also apttofall in the opposite direction due to vibration ofthe assemb ling machine. As a consequence, the pull tab supplied to the assembling machine tends to be improperly positioned, adversely affecting the subsequent pro cess of assembling the pull tab on the slider body.

According to the present invention, there is pro vided a pull tab applicatorforapplying a pull tab to a slider body in a machineforassembling a slide fastenerslider, comprising: a pairof grippers at least one of which is movable relatively away from and toward the other, said grippers being disposed to confronttheface and back, respectively, of a supplied pull tab, said grippers having confronting surfaces, respectively, at least one of said confronting surfaces having a slot for receiving said pull tab therein, said slot being inclined in a direction to bring down the pull tab towards a recumbent position as applied to the slider body; and a drivercoupledto at least one of said grippersfor moving said onegripperbetweenafirst position close to the othergripperto grip the pull tab in said slottherebetween and a second position remote from the othergripperto allowthe pull tabto be brought down in said direction.

It is believed possible by means of the present invention to provide a pull tab applicator capable to bring down a pull tab properly at all times by positively guiding the pull tab in the direction to bring down the pull tab.

The invention will be described by way of example with referencetothe accompanying drawings, where in like references referto like parts unless the context requires otherwise and wherein:- Figure lisa plan view, partlyin cross section, of a pull tab applicator embodying the present invention; Figure 2 is a front elevational view, partly in cross section, ofthe pull tab applicator shown in Figure 1; Figure3 is a plan view, partly in cross section, ofthe pull tab applicator, showing a condition immediately after a pull tab has started to be brought down towards a recumbent position; Figure 4 is a view similarto Figure 3, illustrating a condition inwhich the pull tab has completely been brought down tothe recumbent position;; Figure is a fragmentary vertical cross-sectional view of a slider body and front and rear grippers which are relatively positioned when a pull tab is suplied onto the slider body; Figure6isaviewsimilarto Figure 5, showingthe front and rear grippers immediately after they have started to bring down the pull tab; Figure 7 is a view similarto Figure 5, showing the front and rear grippers afterthe pull tab has fully been brought down; Figure 8 is a perspective view of a slider body and a pull tab as the latter is supplied onto the slider body; Figure 9 is a perspective view ofthe slider body shown in Figure 8 with the pull tab brought down thereon;; Figure loins a perspective view of the slider body of Figure 8with the pull tab assembledthereon; Figure 11 is a perspective view of another slider body and a pull tab as the latter is supplied onto the slider body; Figure 12 is a perspective view ofthe slider body shown in Figure 11 with the pull tab brought down thereon; Figure 13 is a perspective view ofthe slider body of Figure 11 with the pull tab assembled thereon; Figure 14 is a fragmentary plan view of front and rear grippers according to a modification of the present invention; and Figure 15 is a fragmentary plan view offront and rear grippers according to another modification ofthe present invention.

The principles ofthe present invention are particularly useful when embodied in a pull tab applicator generally designated by the reference numeral 10in Figures 1 and 2.

Priorto describing the pull tab applicator 10 in detail, a slider body and a pull tab to be assembled thereon will first be described with reference to Figures 8through 10. As shown in Figure 8, a slider body 11 is composed of a pair of upper and lower wings 12, 13 spaced from each other and intercon nected byaconnector(notshown),theupperand lower wings 1 2,1 3 defining therebetween a generally Y-shaped guide channel 14forguiding a pair of rows of slide fastener coupling elements (not shown). The upperwing 12supportsthereon a cantilevered lug 15 of a substantially inverted U-shapejoined at one end nearthe connector. The oppositefree end ofthe lug 15 is spaced from the upperwing 12, leaving a gap 16 therebetween. A rectangular pull tab 17to be assem bled on the slider body 11 has two holes 18 defined therein near opposite ends thereof. The pull tab applicator 10 essentially operates to supply the pull tab 17 sothatthe pull tab 17is held endways against the upperwing 12 with the lower hole 18 positioned closely to thefree end ofthe lug 15, as shown in Figure 8. Then, the pull tab 17 is translated toward the lug 15 until the lug 15 is insertedthrough the lower hole 1 8to a position 19 indicated bythetwo-dot-and-dash lines in Figure 8.Thereafter, the pull tab 17 is brought down into a recumbent position on the slider body 11 as illustrated in Figure 9. Atthis time, the pull tab 17 is tilted down in a direction away from the gap 16. After the pull tab 17 has been placed on the slider body 11 as shown in Figure 9,the lug 15 is deformed bya punch 20 (Figure 10) in an assembling machine so that the free end of the lug 15is pressed againstthe upper wing 12, closing the gap l6,-w'ereuponaslide fastenerslider21 is completed.

As shown in Figure l,a numberofsliderbodies 11 are placed respectively in recesses 22 defined at circumferentiallyspaced intervals in the upper surface of a circular base 23 rotatable by a central drive shaft 24, the recesses 22 being open upwardly and radially outwardly. The base 23 is intermittently rotated to bring oneoftheslider bodies 11 at a time to a pulltab applying position 25 where the pull tab applicator 10 is located radially outwardly of the base 23.

In the pull tab applying position 25, there is also located a pull tab supply chute 26 (Figure 2) slightly inclined for supplying a succession of pull tabs 17 to the pull tab applying position 25. The pull tab supply chute 26 and a pull tab feeder (not shown) combined therewith may be of any suitable construction which can feed pull tabs 17 successively one by one to the pull tab applying position 25.

As illustrated in Figures 1 and 2, the pull tab appiicator 10 has a pai r of front and rear g rippers 27, 28 which are relatively movable and have respective confronting surfaces 29,30 that are slightly inclined in line with the chute 26. The confronting surfaces 29,30 are normally held closelyto each other in a plane lying in alignmentwith the path of movement ofthe pull tabs 17 along the chute26. More specifically, the confronting surfaces 29,30 are disposed in facing relation to the face and back, respectively, ofthe pull tab 17 supplied from the chute 26 and positioned horizontally between the front and rear grippers 27,28 and positioned substantially vertically between the outlet31 ofthe chute 26 at its lower end and a pull tab applying area 32 on the slider body 11 received in one ofthe recesses 22, as better shown in Figure 5.

The surface 30 ofthe rear gripper 28 has a vertical slot 33 opening toward the surface 29 ofthefront griper 27. The slot 33 is open at its upper and lower ends and is substantially vertically aligned with the chute outlet31 and the pull tab applying area 32. The slot 33 is inclined in a direction in which to bring down the supplied pull tab 17 towards a recumbent position, as indicated by the arrows in Figure 2.

The rear gripper 28 is detachably coupled by a screw 34to the front end of a first slide 35 reciprocably slidably inserted in a first guide groove 36 defined in a support block 37 fixed to a machine base (not shown) by means of a plurality of screws 38. The first slide 35 has a rear end 39 coupled to a driver 40 which moves the first slide 35 back and forth in the firstguide groove 36.

The driver 40 comprises a connecting rod 41 vertically movably supported on the machine base and actuable by means of a suitable actuator such as an air cylinder or a motor, a link 42 pivotably joined to the upper end ofthe connecting rod 41, a shaft 43 fixed atoneendtothelink42and rotatablysupportedon the support block 37, a link44 having one end fixed to the other end of the shaft 43, and a shaft 45 attached to the rear end 39 ofthe first slide 35 and rotatablyfitted in an oblong hole 46 defined in the other end ofthe link 44. The driver40thus arranged can convert vertical reciprocating movement ofthe connecting rod 41 as indicated by the arrow B to horizontal back-and-forth movement ofthe first slide 35 as indicated by the arrow C.

The front gripper 27 is detachably coupled by a screw 47 to the front end of a second slide 48 reciprocablyslidably inserted in a second guide groove 49 defined in the support block 37 parallel to the first guide groove 36. The second slide 48 has a lateral arm 50 disposed nearthe front end ofthe second slide 48 and projecting remotely from the first slide 35. The arm 50 extends in confronting relation to the front end face 51 of the support block 37. The second slide 48 is normally urged to move toward the driver 40 by a tension spring 52 coupled to and extending between a pair of spring retainer pins 53,54 secured respectively to the arm 50 and the support block 37.The second slide 48 has a rear end face 55 which lies substantially flush with or slightly projects from the rear end face 56 ofthe support block 37 when the secondslide 38 is held at rest in its forward position as shown in Figures 1 and 2.

The rear end 39 of the first slide 35 has a lateral arm 57 projecting in confronting relation to the rear end face 55 ofthe second slide 38. The arm 57 supports thereon a pair of vertically spaced adjustment bolts 58, 59 that are th readed through the arm 57 and adjustably locked in position by means of respective nuts 60, 61 threaded over the adjustment bolts 58,59. The adjustment bolt 58 has its tip end held againstthe rear end face 56 ofthe support block37 to hold thefirst slide 35 in position with respect to the support block 37. The adjustment bolt 59 is held endways againstthe rear end face 55 ofthe second slide 48. When thefirst slide 35 is moved toward the base 23, the second slide 48 is also moved therewith by the adjustment bolt 59.

The projecting length of the adjustment bolt 58 which extends between the arm 57 and the rear end face 56 ofthe support block 37 can be adjusted by the nut 60 to adjustthe position of the first slide 35 with respect to the support block 37. The slot 33 can be positioned into accurate alignment with the outlet31 ofthe chute 26 by such adjustment ofthe bolt 58. The projecting length of the adjustment bolt 59 which extends between the arm 57 and the rear end face 55 ofthe second slide 48 is likewise adjustable by the nut 61 to adjust any gap between the confronting surfaces 29, 30 ofthe front and rear grippers 27,28.

Another adjustment bolt 62 is threaded through the arm 50 ofthe second slide 48 and has its tip end facing the front end face 51 of the support block 37. The length of the adjustment bolt 62 between the arm 50 and the front end face 51 of the support block 37 can be adjusted by means of a nut 63 threaded over the adjustment bolt 62. When the second slide 48 is moved toward the driver 40 underthe resiliencyofthe tension spring 52,thetip end ofthe adjustment bolt62 engagesthe front endface 51 ofthe support block 37 to stop the second slide 48 and hence the front gripper 27.

The pull tab applicatorlO oftheforegoing construction operates as follows: When one of the recesses 22 carrying the slider bodies 11 reaches the pull tab applying position 25, the base 23 is stopped, and the non-illustrated pull tab feeder is operated to cause one ofthe pull tabs 17 to slide down the chute 26 by gravity into the slot 33 between the confronting surfaces 29,30 ofthe front and rear grippers 27,28 which are held at rest as shown in Figures 1 and 2. The pull tab 17thus positioned in the slot 33 has its lower portion located in the pull tab applying area 32 on the slider body 11 and is retained between the front and rear grippers 27, 28 as shown in Figure 5.

Then, the connecting rod 41 is moved upwardly to causethe links 42, 44to move the first slide 35 in a direction away from the base 23 toward the driver 40.

Since the adjustment bolt49 is also moved with the first slide 35, the second slide 48 is allowed to move with the first slide 35 under the resiliency of the tension spring 52. The front and rear grippers 27,28 are therefore moved together in unison to displace the pull tab 17 to the position of Figure 6 (which is the same as the two-dot-and-dash-line position shown in Figure 8). Atthis time, the free end ofthe lug 15 passes through the lower hole 1 8 of the pull tab 1 7 with the lower end thereof moving through the gap 16.

Upon continued movementofthefirstandsecond slides 35,48 toward the driver 40, the adjustment bolt 62 on the arm 50 ofthe second slide 48 engagesthe front end face 51 ofthe support block 37, thereby stopping the second slide 48 and hence the front gripper 27, as shown in Figure 3. However, the first slide 35 keeps on moving until the rear gripper 28 is displaced far away from the front gripper 27 as illustrated in Figure 4. With the reargripper 28 moved away fro m th e fro nt g ri p per 27 as sh own i n Figure 7, the pull tab 17 is brought down in the direction ofthe arrow A into a substantially horizontal recumbent position on the slider body 11, as shown in Figure 9.

When the pull tab 17 is completely brought down, the connecting rod 41 of the driver 40 is lowered to enable the links 42, 44to move the first slide 35 toward the base 23. On the movement of the first slide 35 toward the base 23, the adjustment bolt 59 on the arm 57 ofthe first slide 35 engages the rear end face 55 of the second slide 48 and then pushes the second slide 48 toward the base 23 against the resilient forces ofthe tension spring 52. The movement of the first and second slides 35,48 is broughtto a stop when the adjustment bolt58 on the arm 57 of the firstslide 35 engages the rear end face 56 ofthe support block 37.

Before the first and second slides 35,48 are thus stopped, the base 23 is angularly moved by an angular interval equal to the pitch or angular spacing between adjacent recesses 22 for positioning the slider body 11 carried by the next recess 22 into the pull tab applying position 25 in preparation for receiving a next pull tab 17 from the chute 26. The preceding slider body 11 to which the pull tab 17 has been applied is delivered to a next processing station where the lug 15 is pressed downagainsttheupperwing 12 bythe punch 20 (Figure 19) to retain the pull tab 17 on the slider body 1 1.The pull tab applicator 1 then repeats the aforesaid cycle of operation.

ThethicknessWofthe pull tab 17 (Figure 8) can be met by adjusting the distance or gap between the confronting surfaces 29,30 ofthe front and rear grippers 27,28. Such adjustment can be effected by varying the projecting length of the adjustment bolt 58 to adjust the position in which the first slide 35 is to be stopped and also byvaryingthe projecting length of the adjustment bolt 59 to adjustthe position in which the bolt 59 pushes the rear end face 55 ofthe second slide 48. During this adjustment, the pull tab 17 is prevented from being laterally tilted since it is received fully or at least partly in the slot 33.

Figures 11 through l3showasliderbody65ofa different configuration having a pair of lugs 66,67 mounted on an upperwing 68 ofthe slider body 65. A pull tab 69 is positioned between the lugs 66,67 which are thereafter deformed by a punch 70 (Figure 13) to retain the pull tab 69 on the slider body 65. Since the pull tab 69 as itis supplied onto the slider body 65 is not required to be moved longitudinally on the slider body 65, the second slide 48 and hence the front gripper 27 should be kept immovabie with respect to the support block 37. To this end, the adjustment bolt 62 is adjusted to position its tip end against the front end face 51 of the support block37 when the second slide 48 is in the position shown in Figures 1 and 2.

Alternatively, the front gripper 27 and hence the second slide 48 may be fixed with respect to the support block 37, and onlythe reargripper28 and hence the first slide 35 may be moved back and forth with respect to the support block 37. According to a furtheralternative,thetip end of the adjustment bolt 62 may be slightly spaced from the front end face 51 to move the front gripper 27 slightly from the position of Figures 1 and 2 to start bringing down the pull tab 17.

Figure 14shows a modification in which a slot71 is defined in the surface 29 of the front gripper 27 in registry with the slot 33 in the surface 30 ofthe rear gripper 28. The pull tab is received jointly in the slots 33,71.

Where a pull tab has a pair of locking prongs,the surface 29 of the front gripper 27 may have a pairof grooves 72,73 (Figure 15) for receiving such locking prongs, respectively, when the pull tab is located in the slot 33 of the reargripper28.

As described above, the front and rear grippers 27, 28 are detachably fastened to the second and first slides 48,35, respectively. This is advantageous because the front and rear grippers 27,28 may be replaced with different grippers to meet various slider bodies and pull tabs of different shapes. Where slider bodies and pull tabs of only a particular design are contemplated, however, the front and rear grippers 27,28 may be permanently fixed to or integrally formed with the second and first slides 48,35, respectively.

Claims (8)

1. A pull tab applicatorforapplying a pull tab to a slider body ion a machineforassemblingaslide fastener slider, comprising: (a) a pair of grippers at least one of which is movable relatively away from and toward the other, said grippers being disposed to confronttheface and back, respectively, of a supplied pull tab, said grippers having confronting surfaces, respectively, at least one of said confronting surfaces having a slot for receiving said pull tab therein, said slot being inclined ion a direction to bring down the pulltabtowardsa recumbent position as applied to the slider body; and (b) a driver coupled to at least one of said grippers for moving said one gripper between a first position close to the other gripperto grip the pull tab in said slot therebetween and a second position remote from the other g ripper toal low the pull pull .ab to be brought down in said direction.

2. A pull tab applicator according to claim 1, said confronting surface being inclined in said direction.

3. A pull tab applicator according to claim 1 or2, said confronting surface of said other gripper having another slot defined in registry with said first- mentioned slot for receiving said pull tab.

4. A pull tab applicatoraccording to claim 1,2 or3, said confronting surfaceof said other gripper having a pair ofgroovesfor receiving a pair of locking prongs, respectively, ofthe pull tab.

5. A pull tab applicator according to any preceding claim, further including a support block having first and second guide grooves, a first slide reciprocably fitted in said first guide groove, and a second slide reciprocablyfitted in said second guide groove and operatively coupled to said first slide, said grippers being detachably mounted on said first and second slides, respectively, said first slide being coupled to said driver.

6. A pull tab applicator according to claim 5, said first slide having an arm supporting a pair of adjustment bolts engageable with said support block and said second slide, respectively, when said first slide is moved by said driver to displace said one grippertoward said othergripper.

7. A pull tab applicator according to claim 6, further including a spring acting between said second slide and said support blocltfor normally urging said other gripper to move with said one gripperwhile the latter is moving from said first position to said second position.

8. A pull tab applicator according to claim 7, said second slide having an arm supporting an adjustment bolt engageable with said support blockto limitthe movementofsaid othergripperwith said one gripper.