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Publication numberUS2287507 A
Publication typeGrant
Publication dateJun 23, 1942
Filing dateJan 22, 1941
Priority dateJan 22, 1941
Publication numberUS 2287507 A, US 2287507A, US-A-2287507, US2287507 A, US2287507A
InventorsStephen Antonietta
Original AssigneeStephen Antonietta
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Slide fastener machine
US 2287507 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

3 Sheets-Sheet 1 n s. ANTONIE TTA SLIDE FASTENER MACHINE Filed Jan. 22, 1941 June 23, 1942.

5 INVENTOIR.

, BY 2 v v Ammvzx' June 23, 1942. s. ANTONIET TA SLIDE} FASTENER MACHINE Filed Jan. 22, 1941 5 Sheets-Sheet 2 INVENTOR.

June 23, 1942. I v 5 ANTQNIETTA SLIDE FASTENER MACHINE Filed Jan. 22', 1941 s sheets-sheet 5 INYENTOR.

Patented June 23, 1942 UNITED STATES PATENT OFFICE SLIDE FASTENER MACHINE Stephen Antonietta, Port Richmond,- Staten Island, N. Y.

Application January 22, 194-1, Serial No. 375,377

6 Claims.

This invention relates to the manufacture of slide fasteners.

One object of the 'inventionis to provide for the improved, simplified manufacture of slide fasteners by a continuous machine whereby floor space is conserved and constant checking of ac- 'heads and simultaneously indented along U- shaped lines defining the headed fastener elements that were subsequently formed. A high degree of pressure 'was required to provide the heads and the U-shaped depressions, these being formed'simultaneously for speed and accuracy.

The ribbon or flat wire was then wound into rolls which were stocked away, thus completing the first stage of the manufacture. It is pertinent to state that the pressure referred to was applied by means of rolls, which were consideredto ive more accurate reproduction of the die portions in forming the heads than was possible with reciprocatin'g dies, and of course extreme accuracy in the-spacing of, the heads was more readily assured by the use of pressure rolls. The high degree of pressure already referred to required that the rolls be quite massive and powerfully- Inounted so that this apparatus was expensive. Accordingly, the best plant'layout called for a set of pressure rolls for several machines each of which severed the headed flat wire stock into the fastener elements along the U-shaped depressions, and clamped said elements on the stringer tape, completing the second and final stage of the process. Obviously this plant lay-- out required that the pressure rolls be operated at very high speed, which in turn unduly increasedthe wear and stress thereon.

It is therefore an object of the invention to provide a machine whereby the laying up of a stock of headed wire rolls is eliminated and aneven greater speed of production attained, and the cost of the machinery .for the process maintained within reasonable limits, this including wear and replacement of parts.

Another object of the invention is to provide an improved machine whereby relatively light, slowly operating rolls form only the heads, and not the U-shaped depressions, with the headed wire fed directly and continuously to anothq station at which the manufacture is completed, Sometimes the wire members were not fed to the pressurerolls with the extreme accuracy re-' quired and consequently many rolls of the de- ,fective headed wire would be produced and stocked away and the error would not be discovered until they were later used in forming the finished slide fastener. In practise, the latter is frequently inspected as it comes out of its machine.

' It is therefore another object of the invention to avoid this difficulty and this I accomplish by using the headed wire continuously as produced, so that an inspection of the slide fastener manufactured will directly indicate whether an adjustment 'isneeded at the pressure rolls, thus obviating defective slide fasteners and consequent waste.

Whereas the formation ofthe U-shaped depressions according to the first stage of manu- 1 results attained by avoiding the distortion andwinding of the headed wire into rolls, and by a straight line clamping of the elements on the stringer, and by other improvements hereinafter described, including causing the pressure rolls to bear down fiat on the area surrounding the head while the wire was being stretched and deformed to produce the head.

I further found that by providing a set of pressure rolls individual to each cutting and clamping station of the process and thus slow ing up-the heading operation, the heads produced were so much more accurate than before that a feeding device which engages the heads for gaging the feed operates with such accuracy that the initial U-shaped depression formerly caused by the pressure rolls as a guide in cutting out the fastener elements can be dispensed with, and

' extreme accuracy and even greater smoothness assured.

' It is therefore a further object of -theinvention-to provide an improved process which shall embody all the observations noted, and avoid the difliculties while assuring the advantages referred to.

' variations in speed at the corresponding stations.

Another object of the invention is to provide a machine which is of simplified, improved nature for faster omration and greater durability,

-ments on the stringer;

and which costs less to produce and maintain.

Other objects ofthe invention are to provide a machine having improved, more easily adjustable means for clamping the slide fastener eleimproved means for mounting and feeding the stringer tape to' avoid deflection of its support; under strain; improved means for operating the feeding, cutting and clamping means of the second stage by usinga common shaft; simplified cams and connections therefor afiording a high degree of compactness and speed; and in general to provide an improved machine which is particularly adapted to develop the advantages of the new'process.

Other objects and advantages of the invention will become apparent as the specification roceeds.

With the aforesaid objects in view, the invention consists in the novel combinations and arrangements of parts hereinafter described in their preferred embodiments, pointed out in the subjoined claims, and illustrated in the annexed drawings, wherein like parts are designated by the same reference characters throughout the several views.

In the drawings: Figure l is a view in side elevation with parts removed and other parts in dot-dash lines, showing a device embodying the invention.

Fig. 2 is a top plan view thereof.

Fig. 3 is a vertical sectional view taken on the line 33 of Fig. 4.

Fig. 4 is a vertical sectional view taken on the line 4-4 of Fig. 3.

Fig. 5 is an enlarged fragmentary view taken approximately on the line 5-5 of Fig. 2.

Fig. 6 is a bottom plan view of Fig. 5. Fig. '7 is a sectional view on the line 1-1 of Fig. 5.

The advantages of ,the invention as here out lined are best realized when all of its features and instrumentalities. are combined in one and the same structure, but, useful devices may be produced embodying less than the whole.

Itwill be obvious to those skilled in the art to which the invention appertains, that the same may be incorporated in several different constructions. The accompanying drawings, therefore, are submitted merely as showing the pre-' movably mounted a rotary shaft l4 carrying a' reel IS on which is wound a round wire I6. Carried by the top of the frame is a plate H on which is fixed an upright arm l8 carrying a rigid horizontal arm I3, the arms l8, l9 forming any suitable bracket. Rotatably mounted at 20 thereon is a guide roller 2| for the member l6, whereby the latter is fed to the successive wire straightening devices. 22 and 23. These are exactly alike in principle and are used to eliminate kinks in the wire. Thus the device 22'ccmprises a series of rollers 24 mounted on a plate 25 which is affixed to the bracket arm l9, and the device 23 comprises a series of rollers 26 mounted on stub shafts 21 aflixed to said arm I9. The rollers 24 afford a pressure actingon the opposite sides of the wire member |6, and the rollers 26 afford a pressure path acting on other opposite sides of the wire member l6. Both sets of staggered succession of dies.

rollers 24 and 26 are formed with V grooves to receive the wire.

When the wire member l6 has passed through the kink removing rollers 24 and 26, it is received 7 in a heading mill 28, having any guides 28a for the wire at the entrance and exit thereof. The mill may comprise a support 29 and a removable support 2911 fixed on the plate I! and carrying shafts 30, 3| on which are fixedthe pressure rolls 32, 33 respectively, which rotate in the direc tions indicated by the arrows. The rolls 32, 33 form a succession of dies, as the roll 33 is a male and the roll 32 a female member. Thus the roll '32 may have equally spaced cavities 32a in the periphery thereof, and the roll 33 may have equally spaced heads 33a in the periphery thereof to mate with the cavities 32a. to thus form the About the cavities 32, 33 the rolls are cylindrical and are designed to flatten out the round wire member l6. This is facilitated by the working ofthe metal as the heads 33a push the metal into the cavities 32a in forming the heads 34 of the headed wire 35. Moreover, these heads 34 are formed with perfect accuracy, because of the angular engagement and disengagement of the die sections due to the rolling, and because the rolls clamp the wire member tightly around the head 34 that is being formed. Thus the wire is worked and considerably stifi'ened. Further, the rolls 32, 33 may operate at a relatively low degree of pressure, because no other deformation is being pressed out in the wire member, but only the heads 34. And finally, accuracy in a high degree is assured, because while the rolls 32, 33 operate quite rapidly, they do not function at that extreme speed heretofore required by prior processes, for reasons hereinafter apparent.

To drive the mill 28, I mayprovide an electric motor 36 having a pinion 31 engaging a large gear 38 on the shaft 30, which shaft carries a pinion 39 engaging a gear 40 on the shaft 3| so that both rolls 32, 33 are driven with equal power and speed.

From the mill 28, which constitutes the first station, at which the first stage of work is completed, the headed wire 35 is passeddirectly to the second station which comprises the unit 4| which completes the slide fastener as hereinafter described. The unit 4|, for the second stage of the work, is driven by independent means. If the mill 28 produces the headed wire faster than the unit 4| can use it, an automatic switch 42 cuts out the motor 36 to stop the mill. This switch 42 is operated by an arm 43 which is movably responsive to the sag or curve of the wire 35 as shown. This sag or surve is maintained so slight or at a minimum that the path of the stiffened wire may be considered to be substantially straight to avoid bending or distortion as where the. headed wire was wound on reels in the prior art.

The unit 4| may comprise a drive means including a single main shaft 44 which is journaled in a plurality of hubs 45 projecting from the under side of the plate ll which may be of varying thickness for clearance. A drive pulley 46 and a flywheel 41 may be connected to said shaft externally of the machine.

Fixed on the main' shaft 44 are a plurality of like cam blocks spaced from each other. Each of these'eam blocks comprises three cam portions, including an eccentricelement 43 and cam portions 43 and 50 on the opposite sides of the eccentric element. The eccentrics 48 are surrounded by the collars or arms of connecting rods 52 which are of generally U-shaped form as shown in Fig. 4. Thus the lower horizontal arms form the yokes or collars 5I, while the upper horizontal arms 53 are interconnected by a pin I 86 for downwardly bearing on a punching or cutting head I83 as hereinafter in detail described. The cam portions 58 engage rollers 56 on the horizontal arms 51 of the Leshaped lever 58 which is pivotally mounted at 59 on a housing or wall structure 68 that is formed on the plate II. An expansion coil spring 6| between the lever 58 and a wall 68a of the housing 68 causes the roller 56 to be maintained in engagement with its cam 58. Thus the lever 58 operates a feeding means for the headed Wire 35 as hereinafter described. Rollers 62 on levers 63 follow the cam portions 49, being retained in engagement therewith by expansion coil-springs 64 that bear on the'levers, with the latter being pivotally mounted at 65 on the frame or housing 68. The levers 63, which oscillate in planes parallel to the drive shaft 44 carry-at their upper ends opposed adjustable set screws 66 which are thus movable toward and away from each other in a common plane'for operatingthe opposed clamping jaws 61 as hereinafter described. Also eccentrically connected to the main shaft 44 at 68 is a connecting rod 69 which leads to a tape feeding device hereinafter described. Enclosing the main shaft and the different cams and eccentrics is a crank case 18 which may be filled with lubricant.

Mounted on the plate II is a frame II which is in the form of a yoke, and the arms of which are angular as shown in Fig. 3. Formed at the apices of the arms are the bearings I2 for a shaft I3. On this shaft are fixed a taper or stringer feed roller I4 and a ratchet wheel I5. Interme- ,diate thereof, a disc or plate I6 is freely journaled,

against the feed wheel I4 by an expansion coil spring 84 that extends around the guide rod 82. This shoe presses thestringer against the feed wheel to assure proper gripping of the stringer by the latter. If it be desired to relieve the pressure of the shoe 83, to stop the feed of the stringer, a cam lever 85 may be pivotally mounted at 86 on the rod 82, so that when the lever is -swung upward the cam engages the frame porv tion 8| to press downward and pull up the shoe 83 against the tension of the spring- 84.

By mounting the feed Wheel I4 closely adjacent to the ratchet wheel and to the bearings 12, no spring of the shaft'l3 will occur.

In order to assure a proper tension on the stringer, a tensioning device is provided at the lower part of the unit 4|. Preferably a slot 81 hence on the die 88 is adjusted. Thus the latter can frictionally grip the stringer to produce different degrees of tension with the feed wheel I4, which rolls up the finished slide fastener.

The feeding means for the headed strip comprises an L-shaped feed arm 93 disposed within a slot 94 in the lever 58. This slot 94 results in a pair of upward extending arms which form a part of the lever 58, and carry a cross pin 95 havin fixed thereon a cam or eccentric 96 on which the upper end of the feed arm 93 is journaled or pivoted. Thus by turning the pin 95 the eccentric moves the feed arm 93 relative to the pivot 59 of the lever to adjust the throw of the arm during oscillation of the lever, and hence the feed is adjusted. The free end of the horizontal portion of the L-shaped arm 93 rigidly carries a hardened steel feeder head 91 whose bottom overlies the headed wire 35 and is formed with equally spaced cavities for accurately receiving the adjacent heads 34 of the headed wire 35. Accordingly, oscillation of the lever 58 causes a reciprocatory movement of the arm 93 to inter-- mittently feed the headed wire 35 toward the right in Fig. 4, and as hereinafter more fully described.

If it be desired to lock the feed arm 93 out of engagement with the headed wire 35, as in case the stringer is being formed therein, a cam lock may be employed like that at 85. This may comprise a rod 98 connected to the feeder arm 93 and slidable in a plate 99 that is mounted on the top end of the lever 58. Pivotally mounted on the top end of the rod 99 is a cam lever I88 which may be swung upward to upwardly move the rod 99 and hence to upwardly tilt the arm 93 to clear the headed Wire 35. Normally an expansion coil spring I8I- acts between the plate 99 and the feed arm 93 to hold the latter down on the headed are subsequently clamped around the marginal bead of the stringer, I employ a cutter head I83 which is suitably guided by means of side rails I84 and by a center post I84a integral with the members I84 and defining with the latter grooves that receive'the rods 52 and the cutter I833 the members I84 being integral with the casing 68. This cutter is formed with a slot I85 to receive a pin I86 that is fixed to the connecting rods 52,

' while an expansion coil spring I8'I acts between a. top plate I83a attached to the cutter and the member I84 a so as to normally maintain the pin I86 in the lower end of the slot I85. If noslide fastener elements are being .cut, as in the case 'where the machine merely feeds the stringer, it

is desirable that the cutter shall not reciprocate.

' ,In thatcase, the spring I81 is maintained dehaving a large angular entrance is formed in the plate II, this slot leading to a split die 88 which conforms to the shape of the stringer. One half of this die 88 is fixed on a lever 89 pivoted at 98 and actuatedby a tension coil spring 9| connected to an adjustable screw comprising the head 92, whereby the tension on the spring and pressed by any suitable means, not shown, and hence when the connecting rods 52 move upward they will not elevate the cutter, particularly as the vertical length of the slot I is greater than the path of reciprocation of the pin I86.

' It will be noted that the pin I86 is offset horizontally relative to the axis of the shaft 44 so as to produce an increased delayed action at the upper and. lower points in thestroke of the cutv as clearly shown in Fig. 4, the block having an edge conforming accurately to the edge I08 and being in register therewith. The die block I09 may be retained in part by block IIO,,see Figs.

and 7, which afford an open ended keyhole slot III for guiding the stringer and slidably retaining' the bead thereof in the head of the keyhole slot. The blocks 'H0 are in turn returned by plate H2, see Figs. 4 and 5. The arrangement is such that when the headed wire 35 is cut to form a slide fastener element, the latter appears and is positioned as shown at H3 and in register with the head of the keyhole slot I II so that the stringer bead is thus directly received in the fastenerelement H3 between the arms thereof in position for the clamping operation.

To facilitate locking and'releasing engagement between the feeder arm 33 at the head 91 thereof and the headed wire 35, a plunger I I4 is mounted within the die block I09, the plunger having a downward extending rod H5 which is upwardly acted on by a compression coil spring H6. Accordingly the spring H6 elevates the plunger I I4 and hence the overlying portion of the headed wire 35 sol that the heads thereof are in snug engagement with the feederarm 93. Thus the latter can feed the said wire to the cutter. But

.when the cutter I03 moves downward and sev'ers the arms of the fastener element H3 around the stringer bead; then upon the next cycle of the machinathe stringer having moved upward one step, the bars 61 upon their next reciprocation cause their upper jaws I I8 to more tightly clamp the arms of the fastener element around the stringer bead and produce a final shaping thereof. For retracting the bars 61 and keeping them in contact with the set screws 66, tension coil springs IIS are connected to upright pins on the clamp bars 61 and on their adjacent levers 63.

It is seen that the clamping bars 61 move in a straight path, being always alined with each Moreover, the clamping action along a straight an element H3, the cutter depresses the adjacent part of the headed wire 35 and hence the plunger H'4 against the force of the spring H6. This depressing of the headed wire is just suflicient to disengage the heads thereof from the feeder arm 93, and the latter is simultaneously retracted. When the cutter moves upwardthe plunger HI raises the headed wire back into engagement with the-feeder arm 93, and the latter is simultaneously moved to feed another portion of the headed wire to the cutter I 03.

It will be noted that the cutter I03 and the die I09 perform the cutting operation although the headed member has not been previously formed with a U-shaped depression as a guide or starting line for the cutter. This is rendered possible in part by extreme precision of the parts and by causing the cutter face at the right in Fig. 4 to wipe closely. against the base of the head 34 of the element 35, the head being actually of somewhat conoidal form with its maximum area being at the base. By such close cuttingat the base, the mass of metal forming the head facilitates a smooth, clean and accurate cut by the cutter I03 so that the results attained are as good as those'obtained with the preformed U'- shaped depression heretofore used.

For clamping the fastener element H3 on the stringer bead in the position of Fig. 4, the set screws 56, see Figs. 3 and 5, carried by the levers 63, actuate .the clamping bars 01 which are slidably mounted in the fixed blocksHI, each bar 61 having a lower and upper jaw H0, see also Fig.4, the upper jaws being longer and hence closer together than the lower jaws. The purpose of this arrangement is that the lower jaws HI cause the first clamping action by Squeezing line permits attainment of a high degree of clamping, with the pressure localized at the precise points desired, as against the angular clamping pressures heretofore employed. Moreover, this straight clamping pressure is peculiarly adapted for use with fastener elements H3 which have been cut without a preformed U-shaped depression in the headed wire35, because if any roughness results due to dulling of the cutter edge, this straight line clamping pressure is better adapted to cause the jaws to press down and smooth out any roughness of the fastener elements that may result.

As the slide fastener is produced and is being wound on the .feed wheel I4, the operator can readily inspect theslide fastener from time to time and ascertain whether it. is wholly accurate or whether the mill 23 requires adjustment, as in the event that the heads 34. are not being formed along the true center line-of the wire 35. This avoids a condition which formerly occurred where many reels of defective headed wire were produced,'and the error was not discovered until the headed wire was actually used to make the slide fastener. the mill 28 works in conjunction with one'unit ll it operates at less speed, assuring greater accuracy, but this in turn permits the unit 4| to operate at a higher speed than heretofore for this and the other reasons herein indicated.

Since only one main shaft l4 operates all the moving parts of the unit I, and since all the parts as well as their motions are relatively simple, the speed of the unit II is greater than was heretofore possible. All the lineal movements are not in excess of approximately one sixteenth of an inch, reducing vibration and prov longing the life of the machine. I

It is now seen that 1 have provided a highly advantageous continuous process for the manufacture of slide fasteners with the use of a relatively light mill 20 which is thus sufficiently cheap so that one can be used-with each unit ll,

for the respective first and second stages of the requiring storage thereof and without distortion:

of the headed wire, while the condition of the latter as produced may be readily checked and adjusted by the customary inspection of the finished slide fastener as produced. with the Iother features herein described in detail, the

It is also noted that since-v process is rendered operative and advantageous in a high degree.

With the process according to this invention, the mill 28 of course produces the heads facing in the proper direction for operative mounting on the-stringer. In the prior art process, where the headed wire was rolled up on reels, the heads were formed in reversadirection, in other words, as if a ratchet wheel were turned around for reverse operation, the heads 34 being shaped somewhat like ratchet teeth. The slope of the heads 34 is gradual at their left and steep on the right, and this also allows for easier separtion of the roll 32 from engagement of 'its cavities with the heads 34.

I claim:

1. A machine for making slide fasteners having U-shaped headed fastener elements spaced along a stringer on which they are clamped, including a first means for feeding a headed wirelike member step by step according to the spacing of the heads along the member, a second means for cutting said member into said U- shaped elements, a third means for clamping said elements on a stringer, a-shaft, and cam means thereon including a plurality of like spaced cam blocks each having cam portions for actuating the first, second and third means.

2. A machine for making interlocking headed slide fasteners secured on stringers, including feeding means for a wire having spaced fastener heads thereon comprising an element oscillating back and forth, an arm pivotally mounted on said'element and having. a portion for engaging over the heads to feed the wire forward step by step according to the oscillation of said element, and means for adjusting the arm, said the latter being spaced along the stringer path so that one of the clamps secures an element on- 5. A machine for making slide fasteners in-- cluding a die comprising a cutter, a plunger for actuating the cutter, means for intermittently feeding to the die a wire having spaced heads so that the cutter shall sever the wire to form a succession of fastener elements to be secured to a stringer, the feeding means being movable to inoperative position, means for feeding a stringer, reciprocatory means for actuating the plunger, lost-motion means interconnecting the plunger and the reciprocating means, said lost-motion means having a limit of relative movement between the plunger and the reciprocatory means, resilient means acting between-the latter and the plunger to maintain a relative position at said limit of movement such that the plunger shall be actuated by the reciprocatory means to operate the cutter, said plunger being adapted to be retained against the force of the resilient means cooperating with the arm and the element to vary the stroke of said feeder portion, said means including an eccentric member about the axis of the pivot of said arm, said member being rotatably adjustable.

3. A slide fastener machine including means for horizontally feeding a rod having spaced fastener heads, including *an upright lever, an

-rectly between the cam and the plunger for L-shaped arm pivotally mounted at its upper end on said lever above the pivotal mounting of the lever, the arm having a horizontal portion extending away from the lever, said horizontal portion having a head engaging portion adjacent to its free end, an eccentric at the pivot of said 1 arm for adjusting the stroke of said head engaging portion, and means for causing oscillation of said lever.

4. A machine for making slide fasteners including means for clamping the legs of the slide fastener elements on a. stringer, means for intermittently feeding said elements in one path and the stringer in a path at an angle thereto, the clamping means comprising a pair of members movable toward and away from each other, each member having at least two stepped jaws and the jaws on the different members cooperating with each other to form a plurality of clamps,

means in a different position relative to the plunger so that reciprocation of the reciprocatory means shall not cause actuation of the plunger, and a common means for operating the reciprocatory means. and the feeding means, whereby the feeding of the stringer can continue without the production of fastener elements by the cutter in the inoperative position of the feeding means.

6. A machine for making slide fasteners including a die for severing from a headed wirefastener elements to be secured to a stringer, a vertically acting plunger for actuating the die, a shaft having a cam, a connecting member dicausing reciprocation of the latter upon rotation of said shaft, said plunger making one reciprocation for each rotation of the cam to thus provide a dwell at the upper and lower ends of the plunger path, and means engaging the connecting member with the plunger at a point offset from the vertical plane passing through the axis of said shaft to thus provide a leverage for accentuating the dwell caused by said cam, means for feeding said wire to the die including a reciprocating head engaging'member for said wire for releasably successively engaging differentheads to feed the wire, and common means for operating the feeding means and the shaft, whereby the plunger affords ample dwell to permit disengagement of said heads and retraction of said member when the plunger is lowered past cutting position and to permit engagement of other heads and advance of the wire by said member when the plunger is in retracted upper position.

STEPHEN ANTONIETI A.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2444706 *Aug 12, 1944Jul 6, 1948Loew SigmundSlide fastener machine
US2744561 *Nov 25, 1949May 8, 1956W E Cuckson & Son LtdMachine for use in the manufacture of zip fasteners
US2753182 *May 3, 1950Jul 3, 1956Anchor Slide Fastener CorpFeeding disks in slide fastener machines
US4809414 *Nov 13, 1987Mar 7, 1989Yoshida Kogyo K. K.Apparatus for manufacturing bidirectionally openable slide fasteners
US6073699 *Mar 6, 1998Jun 13, 2000Weatherford/Lamb, Inc.Single joint elevator
DE971235C *Jan 1, 1949Dec 31, 1958David SilbermannVerfahren und Vorrichtung zur Herstellung von Reissverschlussgliederstreifen
Classifications
U.S. Classification29/33.2
International ClassificationB21D53/00, B21D53/50
Cooperative ClassificationB21D53/50
European ClassificationB21D53/50