US2444706A - Slide fastener machine - Google Patents

Description

S. LQEW SLIDE FASTENER MACHINE Filed Aug. 12. 1944 Patented July 6, 1948 SLIDE FASTENER. MACHINE Sigmund Loew, Windsor, Ontario, Canada Application August 12, 1944, Serial No. 549,236 In Canada July 25, 1944 s claims. 1

This invention relates in general to machines for the manufacture of slide fasteners, and more particularly to automatic machines for the manufacture of slide fastener stringers from which the finished slide fasteners are made.

The primary object of this invention is to provide a single machine for the complete manufacture of slide fastener stringers, wherein the operation is continuous.

Another object is to provide an improved machine for making slide fastener elements from stock wire with a minimum of waste.

Still another object is to provide greater precision in the attachment of the slide fastener elements to the Stringer tape.

It is also an object of this invention to provide a slide fastener stringer of more durable construction.

Still another object is to reduce cost of operation in the manufacture of slide fastener stringers.

The foregoing objects together with others will Ibe apparent from the following description considered in connection with the drawing in which:

Figure 1 shows a plan of the more important stages of operation.

Figure 2 shows an elevation of the main part of the machine.

Figure 3 is a diagram of the general arrangement of the machine in combination with a standard power press of which it is a part, and

Figure 4 is a front elevation of the spacer mechanism for spacing the fastener elements on the tape.

' The machine as shown in the drawings, consists of an upper die I and a lower die 2. The stock wire which is fiat is fed into the lower die 2 as shown at 3. When the wire 3 reaches the first station in the die 2 it is immediately over a forming die 4 which is supported on a spring or a plurality of springs 5. A punch 6 which is located in the die I constitutes the upper part of the die 4 so that when the die block i comes down, a cavity 'l is formed in the wire, generally of the shape shown in Figure 1. This cavity will hereinafter be referredto as the embryo.

The upper die I and lower die 2 are used in combination with a press. The upper die block i`s attached to the pitman of the press and the lower die block is fixed to the table of the press.

The lower die block 2 is provided with a reciprocating finger 8 which is pressed against the wire 3 at the point where cavity 'l has been formed, by means of a spring 9. The finger 9 is pivotally attached to a movable section I9 which is part of the die block 2. The section Ill is provided with a cam II, and the die block I is provided with a corresponding cam I2. When the die I comes down to punch the embryo l, the cam I2 slides against the cam II thus pushing section I0 with its attached finger 9 out of the way of the descending punch 6. When the punching operation of 6 is completed, the die I ascends allowing section I0 to move forward due to the action of spring I3. The finger 8 moves forward with the section I0. The point of the nger 8 is made so that it fits into the embryo 1, so that when the finger moves forward it pulls the wire 3 along with it so that the wire is advanced a predetermined distance. The distance the wire is advanced is determined .by the following arrangement. A threaded bolt Ii is screwed into a tapped Iblock I5 which is part of the die 2. One end of this bolt is provided with knurled head I6. and the other end of the bolt is provided with a stop I'I. The cam II is bored with a hole to permit the passage of the bolt Ill, but said hole is small enough to prevent the passage of the stop Il, so that by adjusting the length of the bolt I4 between'the block I5 and the cam I I, the movement of the section .I9 and the finger 8 is determined. A setscrew I8 locks the bolt I4 into position.

A plurality of embryos 'l are punched in the wire before said wire reaches the next stage of operation. At this stage the wire passes between a lower punching die I9 which is supported on a spring 29, and an upper die 2| which is part of the die block I. An enlarged diagram of this set of punching dies is shown in Figure 1, where the action between the die I9 and the die 2i punches out a serration 22 on either side of the wire 3. The punched scrap 23 is blown away by means of compressed air through the pipe 24' which is situated in the grooved part of the die punch 2l. The die 2i is also provided with a semi-circular cutting edge for the purpose of cutting out a semi-circular section as shown at 25, the use of which will be described in connection with the nal stage in the making of the slide fastener stringer.

The nal stage in the operation of the machine may be more fully comprehended by reference to both Figures 1 and. 2. The lower die block 2 is also provided with a guiding block 26 which has a slot 2l for guiding the stringer tape 28. As this tape is usually finished on one of its edges with a pair of rounded cords 29, a circular guide 30 is also provided in the block 26 to accommodate the said cords. When the wire 3 reaches the position where the cord 23 nests within the died out section 23 which forms the inner wall of the element, the jaws 3| become located between two opposite clamping hammers 32 and 33. The die I is provided at this point with a pair of cams 34, 34. On the downward stroke of the die i the cams 34, 34 compress the hammers 32 and 33 against both sides of the element jaw 3| so that the element becomes permanently clamped to the tape 23 at its corded edge.

Throughout this entire operation the individual element as indicated by 3l remains an integral part of the wire 3, and only after the jaws have been clamped onto the tape, the element 35 is severed from the wire 3 along the line 25 b y the die 2|. 'Ihis of course gives greater stability to the individual element than is provided in existing machines where such elements are individually and separately attached to the tape, thereby providing a greater degree of precision to the spacing of the elements on the tape.

The tape 23 is fed into the machine in a vertical position. It is held stretched to the required degree of tension between the reel on which it is originally wound and a spacing mechanism such as is shown in Figures 3 and 4. To an eccentric wheel 3B which" is attached to the press shaft 31, is pivotally attached an arm 38 whose length is adjustable by means of a. turnbuckle or some such mechanism 39. The arm 33 is also pivotally attached to a horizontal arm 43, the bearing at thisl point being on a movable block 4I for the purpose of adjusting the location of this bearing along -the arm 40. One end of the arm 40 is eccentrically attached to a friction clutch 43. Shaft 44 is supported by bearings 4S and 43 which are in turn supported by the walls of the press. -A knurled wheel 41 is mounted on the shaft 44 in a position above the guide block 24. The tape with the fastener elements attached thereto which will now be referred to as 28' rolls over the wheel 41 and is held tightly pressed against the knurls by an upper wheel 4B. v The wheel 41 is attached to the shaft 44 by means of a friction clutch 49 which is directly attached to the shaft 44, and the clutch 43 is similarly attached to the said shaft. The clutches 43 and 4l are so arranged as to provide rotation to the shaft 44 in one direction only so that one stroke caused by the eccentric 36 `turns the shaft 44 while the return stroke has no effect upon said shaft. Thus an intermittent movement is imparted to the tape. the intermissions providing the proper spacing to the fastener elements 35.

In actual practice the machine operates in the following manner, although it is not intended thereby to limit this invention to the specic ngures which follow. The flat wire is -fed into the die and is moved forward by the reciprocating finger pushing on the embryo which has been drawn in an inverted position in the first station of the die. After the wire has fed forward twenty-seven times it is now in a position for the notching dies to function. These also are inverted with themale die being in the lower portion. At this point the only blanking out of the entire process takes place, and the wire leaving this point has the embryo formed therein and serrated edges. The strip continues to be fed forward so that`it now lays on the die which blanks the element ofi the strip of wire. In order that the element that is to be cut off be held stationary while it is being attached to the tape, the

cams that close the hammers now engage the said hammers so that the closing of the element jaw upon the tape takes place before the shearing off of the element is completed. In order that the element remain on top of the blanking die. the wire which is progressing through the die has to go down under the blanking punch, notching punch, and the impresseion punch. These punches are all the same length and therefore carry the wire down evenly, while the wire is thus going down it is supported by spring loaded pads which on the upward stroke of the press return `to their normal level. The entire pro-l cedure is intermittently repeated.

The machine is also provided with a catch lili in the lower die block 2 at the entrance of the stock wire. This catch is pressed against the stock wire by a spring 5l. The catch is at an angle leaning away from the direction in which the wire 3 travels, so that the sharp edge of the said catch prevents the wire from backing out of die.

It is obvious that changes might be made in nonessentials of the structure of the machine while retaining the essentials of the invention and I do not consider it 1imited to the specic construction shown; therefore what I claim is:

1. An automatic machine for the manufacture of slide fastener stringers in combination with a press, comprising an upper die block which is attached to the pitman of the press and a lower die block which is xed to the table of the press. a series of upper and lower dies or punches for successively drawing an embryo cavity, serrating the edges, and punching of! individual elements from a stock wire, means for clamping said elements to a standard tape, and means for feeding said stock wire to the successive stages in the operation comprising a sliding section which is part of the lower die block, a reciprocatingv nger which pushes the stock wire by engaging the embryo cavity and which is part of said sliding section. a spring in compression which presses against one end of said finger to provide engagement between the finger and embryo in the stock wire. a cam in the upper die block which engages a corresponding cam on said sliding section which retains the reciprocating finger, a compression spring between said sliding section and a fixed part of the lower die block, reciprocating motion being provided by the action of said cam and spring. and means for controlling the extent of said motion including a threaded bolt which limits the motion of the sliding section imparted by the Acam on said sliding section.

2. A machine for the manufacture of slide fastener stringers comprising in combination upper and lower die blocks for relative movement toward and from one another with reciprocating motion, punch and die means carried by the respective die blocks and operable with each reciprocation of the die blocks to form an embryo cavity in fiat stock wire positioned between the die blocks, apparatus for feeding the stock wire forward including a finger that slides back and forth lengthwise of the fiat stock wire with each reciprocation of the die blocks and in constant contact with the stock wire and against metal displaced by the operation of the punch and die that form the embryo cavity, finger-supporting and reciprocating mechanism carried by one die block. abutment means carried by the other die block in position to operate said mechanism for ,moving the nnger with each reciprocation of the die blocks, and other die means carried by the die blocks, and to which the stock wire is fed by said linger, for shaping the end of the stock wire into one end of a slide fastener element, and for cutting off the end portion of the wire stockvto complete the slide fastener element after the element is 4in position astride a tape.

3. An automatic machine for the manufacture of slide fastener stringers including in combination a press, an upper die block attached to the pitman of the press and a lower die block xed to the table of the press, a series of cooperative punches and dies carried by the die blocks for successively forming an embryo cavity, shaping the edges, and punching off individual elements from a stock wire after said elements have been successively advanced to positions astride a tape, clamping mechanism carried by one of the die blocks for clamping individual elements to the tape, deciprocating feeding mechanism carried by one of the die blocks for feeding the stock wire with a step-by-step motion past the successive dies and punches and to said clamping means, abutment means on one of the die blocks for operating the clamping mechanism and the feeding mechanism carried by the other die block with each stroke of the press, a spring for returning the feed mechanism after each stroke, a finger comprising a part of the feeding mechanism with an end portion that engages metal displaced by the forming of the endmost embryo cavity, and means for holding said end portion of the finger-in contact with the stock wire.

4. A machine for the manufacture of slide fastener stringers comprising in combination with a press, a reciprocating finger operated by the movement of an upper die block connected to the pitman of the press for intermittently feeding the stock wire from which slide fastener elements are made, upper and lower die combinations for punching embryos in the stock wire,

a. notching die adjustably attached to the upperl die block and a complementary notching die in a lower die block supported by a compression spring, the upper and lower notching dies being for the purpose of serrating or notching the edges of the stock wire to form the outer contour of the jaw of the fastener element, said die combinations also including means for shearing oi the individual fastener elements from the rest'of the stock wire after each of said elements has been brought into a position astride a standard slide fastener tape, and means for attaching the elements to the standard slide fastener tape.

5. A machine for the manufacture of slide fastener stringers comprising in combination with a press, a reciprocating finger for feeding stock Wire, dies for drawing embryos in said wire, dies for forming the edges of said wire and punching the individual fastener elements from the said stock wire, means for clamping the said elements to standard Stringer tape, and means to feed the tape to space the fastener elements thereon including a shaft which is supported from the walls of the pressabove the upper die block, a knurled wheel mounted on said shaft by means of a friction clutch, a second friction clutch which is attached .to the end of the shaft, an oscillating ar'n which is attached eccentrically to the second friction clutch and operatively attached at its other end to said main shaft, and a connecting rod between the said eccentric on the press shaft and the osculating arm, so that upon the rotation of the press shaft an intermittent motion in one direction is imparted to the spacer shaft and the knurled wheel thereon, and to the slide fastener Stringer between the said knurled wheel and a pressure wheel provided for that purpose.

SIGMUND LOEW.

REFEBEN CES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,078,017 Poux Apr. 20, 1937 2,201,068 Wintritz May 14, 1940 2,287,507 Antinietta June 2, 1942 2,299,606 Wintritz Oct. 20, 1942 2,302,075 Ulrich Nov. 17, 1942 2,310,660 Ulrich Feb. 9, 1943 2,336,662 Wintriss Dec. 14, 1943 2,338,884 Ulrich Jan. 11, 1944

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