US2075168A - Wire forming machine - Google Patents

Description

March 30, 1937. D. L. BROWN WIRE FORMING MACHINE 4 Sheets-Sheet 1 Filed April 29, 1935 RNEY % & i

March 30, 1937.

D. 1.. BROWN WIRE FORMING MACHINE Filed April 29, 1935 4 Sheets-Sheet 2 INVENTOR DAVID 1.. BROWN RNEY March 30, 1937. BROWN 2,075,168

WIRE FORMING MACHINE Filed April 29, 1935 4 Sheets-Sheet 3 INVENTOR DA W0 A. BROWN mxm.

A ORNEY March 30, 1937; BRQWN WIRE FORMING MACHINE Filed April 29, 1955 4' Sheets-Sheet 4 INVENTOR 04 V10 L. BROWN BY 8% RNEY Patented Mar. 30, 1937 UNITED STATES WIRE FORliflNG MACHINE David L. Brown, Summit, N. 3., assignor to Trussell Manufacturing Company, Poughkeepsie, N. Y., a corporation of New York Application April 29, 1935, Serial No. 18.7 34

23 Claims.

This invention relates particularly, though not exclusively, to the forming of wire with 'reverse bends, providing the effect of a strip of transversely extending wire fingers connected in spaced substantially parallel relation.

' By suitable bending operations these connected wire fingers may be shaped to form the holding elements of a ring binder.

. It is essential for such use that the wire fingers be practically parallel, so that in the final shape they will hold the sheets in the binder in proper register. To be practical also, this special wire strip material should be relatively inexpensive.

Important objects of the present invention are to enable production of strip material of the character referred to accurately, rapidly and inexpensively and to provide a machine for the purpose, which will be of as simple design and low cost as possible and which will be entirely practical and emcient for the purposes intended.

Additional objects and the novel features of construction, combinations and relations of parts by which the objects in view have been attained will appear and are set forth in detail in the 5 course of the following specification.

. The drawings accompanying and forming part of the specification illustrate certain practical embodiments of the invention, but it will be apparent as the specification proceeds that the structure may be modified and changed in various ways without departure from the true spirit and broad scope of the invention.

Fig. l is a broken planytview of one of the machines showing the wire of strip material going in through a stock straightener at the left hand side of the machine and coming out as a formed zig-zag binder strip at the opposite side of the machine.

Fig. 2 isa broken sectional view as on a generally central plane indicated by line 22 of Fig. 1 and illustrating in particular the feed slide and related parts.

Fig. 3 is a broken transverse sectional detail as on substantially the plane of line 3-3 of Fig. 1.

Fig. 4 is a similar view as on substantially the plane of line 4-4 of Fig. 1.

Fig. 5 is an enlarged broken detail illustrating .in solid and in broken lines particularly the operation of the reversely acting bending fingers.

Fig. 6 is a broken sectional detail of hold-down plungers as on substantially the plane of line 5-5 of Fig. 1.

Fig, '7 is a broken sectional detail on a larger scale as on substantially the plane of line 'I'| of F18. 5.

Fig. 8 is a broken bottom plan of the bending fingers in the cooperating relation forming the final bend.

Fig. 9 is a perspective view of one of the dies for holding and imparting the final set to the bends in the formed strip of material.

Fig. 10 is a broken plan view illustrating modification of details of forming dies and stock holding clamp.

Fig. 11 is a broken and part sectional side ele- 1 vation of the latter mechanism.

For a quick understanding of the general principles of the invention, attention is first directed to Fig. 1, where the final product of the machine is indicated at the right issuing from a guide 15, 1 as a strip composed of substantially parallel transverse lengths of wire l6, connected by narrow bends l1, and forming fingers connected in spaced relation by the wider bends l8.

The wider bends are made around the point of 5 a holding and setting die 19, by an arcuately acting bending finger 20, and the narrower bends are made around the point 2|, of this first bending finger by a second sequentially acting bending finger 22.

After these bends are thus made, the bending fingers 22 and 20, may open up in this reversed order and the die IS, with the co-acting' die 23, which have held the previously finished bends, separate to permit the work being advanced one step by the feed slide 24.

As the bending and holding dies 19, 23, open up, a pad 25 on the feed slide comes down and grips the work, so that it will be advanced with the slide.

In some instances, a holddown plunger indicated at 26 comes down to momentarily grip the work as the dies I9, 23 separate.

To aid in the feeding operation and to overcome any tendency of the finished stock to drag 4 the work out of the machine, there may be provided a spring feeding and detent pawl 21, on the inner end of the feed slide for engaging the strands of the finished strip.

The strip stock, which in this case is the wire, 4 is shown at the left in Fig. 1, at 28, entering between straightener rolls 29, on the feed slide and passing thence through a relatively wide wire guiding throat 30, for holding the wire down to a constant level while being acted on by the bend- 5 ing fingers.

Previous to entering the machine, the stock preferably is carefully straightened and in the machine, care is taken to deflect it only at points where bends are to be located. In carrying out 5 this idea of preserving the parts which are to be straight in their original straight condition and bending the stock only at the intended points of bend, the bending fingers are made to engage the wire at those exact points where bends are to be located. Forming is thus accomplished without wiping along the wire and hence the bends are definitely and exactly located without any creeping effect.

Considering details, the base of the machine illustrated, comprises a table structure 3|, on which the various parts described are mounted and which has at the sides of the same the front, back, left and right hand cam shafts 32, 33, 34, 35, respectively, connected by bevel gearing 36.

As shown particularly in Figs. 2, 3 and 4, the feed slide 24, is reciprocated longitudinally of the wire line in a guide channel 31, by the reversely acting earns 38, 39, on the left hand cam shaft 34, engaging the spaced cam rolls 46, 4|, on the underside of the slide.

The pad or clamp 25 for holding the work down on the feed slide is shown as carried by an arm 42, pivoted on the slide at 43, and tensioned by an overstanding spring 44.

In the first form of the invention disclosed, the work clamp of the feed slide is raised as in Fig. 4, by being wedged up to that position by the bevelled ends 45, at the inner ends of the dies I9, 23, acting as wedges engaging beneath the angularly undercut sides 46, of the pad.

In the second form of the invention as illustrated in Figs. 10 and 11, the feed slide clamp is lifted by means of a cam 41, on the right hand cam shaft 35, acting on a lever 48, having a lifting engagement with the work holding pad lever at 49.

The timing of this cam is such as to lift the pad on the outward retractive stroke of the feed slide and to lower the pad at the end of this outward movement to effect the feed of the stock on the inward stroke of the slide. I

The first bending and holding die I9 is shown carried by a slide 50, Figs. 1 and 4, having a cam roll 5|, engaged by cam 52, on the back cam shaft 33.

Similarly, the companion bending and holding die 23, is showncarried by a slide 53, carrying a roll 54, engaged by cam 55, on the front cam shaft 32.

In the first form of the invention Shown, the companion bending and holding dies I9, 23, are of multiple design, the first having duplicate bending and holding fingers |9a and SD and the second having a second duplicate bending and holding finger 23a, these mating or meshing as indicated particularly in Fig. 1.

In the'simpler form of the invention shown in Fig. 10, only two mating die fingers are employed, these being simply designated l9 and 23. The

latter view illustrates also how these die fingers may be shaped to produce relatively abrupt angu lar bends instead of the more rounded bends produced in the first form of the machine.

As shown particularly in Figs. 2, 4 and '1, the companion die fingers are formed at thebottom with mating wire receiving grooves 56, along the sides and about the ends of the same to receive, position and positively hold the wire.

In similar fashion, the first bending and forming finger 20, is grooved at 51, entirely about the lower edge of the same, as appears in the detail view, Fig. 8, and the second bending finger 22 is grooved at 58, along the edge facing the back or outer portion of the first bender and about the point of the same.

As shown in Fig. 7, the forming dies and bending fingers operate immediately over the smooth fiat top surface of the feed slide 24, so that the latter thereby forms a closure to the mating wire receiving grooves 66, 51, 56, in the lower edges of these forming tools. As appears also in this view, the second .bending finger has a mating engagement at 69, beneath a correspondingly shaped overstanding shoulder on the back of the first forming tool 20. This assures accurate register and .coaction of the two so-called bending fingers.

The first or front bending finger 26 is shown as pivoted on a stud 66, on a transversely acting slide 6|, having a cam roll 62, engaged by a cam 63, on the front cam shaft 32. A spring 64, thrusts this finger outwardly against a roll 66, on a stationary mounting bracket 66, the outer vedge of the finger thus riding over this roll as a camin the reciprocating movement of the slide 6|.

The parts are designed so that upon the inward movement of the slide 6|, the tip of the first bending finger 26, will engage the wire extending out from around the die l3, at the point 61, indicated in the broken line position Fig. 5, and will carry that point on the are 63, to the outer shoulder 63, at the root of the shaping die I8. One bend is thus made about the tip of the stationary die l9, and a second bend is started at a definite point 61, on the wire without any slipping or wiping action.

The second bending finger 22 is shown pivoted on a stud on a slide 1|, having a roll 12, engaged with cam 13, on the back shaft 33. This second finger is shown as actuated from a cam 14, on the left hand camshaft 34, Fig. l, engaging a roll 15, on an upright lever 16, pivoted at its lower end at 11, Fig. 2, and having a universal fitting 18, at its upper end pivotally connected with the bending finger by an adjustable link 13.

The two cams described are related to effect the operation in broken lines indicated in Fig. 5, that is, to bring the tip of this second forming lever into contact at 80, with the stretch of wire extending out around the tip 2|, of the first bending finger and to carry this contacted point on the wire on the arc 8|, closely into the curve of the shoulder 82, Fig. 8, at the root of the first bending finger.

Accordingly, the third bend of the stock is accomplished, starting at the point of bend and without slipping or wiping that bend along the wire.

Thus by the means described, the wire is kept straight except right at those points where bends are required and the bending is started and finished at those contacted points. In the forming operations therefore, no undesired bends or bending tendencies are applied or imparted to the otherwise straight wire and the lengths of wire between the bends are permitted to remain in their original straight condition.

The bends placed in the wire through the described coaction of dies and bending fingers are fixed and given a permanent set in the step-bystep action of the interfitting overlappingdies I3, 23, etc.

If found desirable, the bending fingers may break the wire slightly beyond true parallelism of the transverse strands, so that any remaining spring will simply bring these strands back to true parallelism, which is fixed in the subsequent engagement of the same in the co-acting sliding dies.

As will be noted particularly in'Figs. 2 and 11, the wire guiding slot 80, holds the wire down to the plane of the feed slide and directly in line with the wire confining grooves 56, 51, 58. In the latter view, an overstanding wide flange 83, confines the wire down in this plane as it is swung back and forth first by one and then by the other bending finger.

The device for holding the finished work heretofore referred to in a general way as the plunger 28, actually consists in the form illustrated in Figs. 1, 2, 6 and 7, of a pair of plunger stems ll, carried by a head 85, on the end of a rock lever 88, and operating down through guides 81,.

to grip parallel strands of the finished material. This lever is shown in Figs. 1 and 2, as pivoted at 88, and carrying a roll 89, in engagement with cam 90, on the right hand cam shaft 35, and as being tensioned in the work gripping direction by spring 9|. When used, this work holding clamp may be timed to grip that part of the work which is clear of the sliding dies only when there is no advancing movement of the work.

The work feeding and detent pawl 21, Figs. 1, 5 and 7, may be simply in the form of an overstanding spring strip on the end of the feed slide, shaped substantially as indicated in Fig. 'I, to engage between the strands of finished work to aid in advancing the material out through the guide l5, and to prevent the weight of any length of finished material hanging from the guide exerting too much of a pull on the work passing through the machine.

Ordinarily, it is unnecessary to have a series of the interfitting die fingers as at l9, l9a, Nb and 23, 23a, Fig. 1, just two of these reversely operating coacting fingers being sumcient as indicated in Fig. 10.

Also under average conditions, the work holding clamp 26, Figs. 1 and 2 may be dispensed with. These latter two conditions make it possible in a construction like that shown in Figs. 10 and 11, to set the work holding pad 25, on the feed slide in the space 92, provided between the opposing ends of the two die slides. Fig. 10 also shows how the second bending die 23, may be made of less than full length and the pad be out out at the corner at 93, to accommodate this short finger and be extended for the rest of its width close up in back of the first bending die 19. This thus locates the clamp as close as possible to the actual forming operations.

The bending tools may be shaped to form more nearly angular than the curved bends shown. The finished strip material may feed out of the machine in continuous lengths and be wound on reels or otherwise handled. If desired, the

strip material may be cut in predetermined lengths in the machine. The machine may be adapted to and employed for handling other forms of strip stock than wire. While particularly adapted for producing a strip product for binders, it will be understood that the machine may be used for producing various other kinds of material or articles. Also, it will be appreciated that while the structures shown are considered as preferred embodiments of the invention, many changes may be made all within the broad scope of the following claims. I

When the stock is straightened before reaching the machine, as is desirable, the straightener rolls 29, may be set and used primarily as a guide and as a means for applying a certain tension or drag" to the stock, thus to keep the wire taut and free of any slack while the tools are operating on the same.

It is to be noted that the formed portion of the stock remains attached to the supply length of stock. The operation can thus be continuous and uninterrupted. The coacting dies I9, 23, hold the immediate previously formed portion of the strip stock, the wire grooves 56, about the bases of the same providing passage for the wire to which this portion remains attached. The operation of the first forming or bending tool 20, is then simply to break this issuing portion of wire about the point of the first die member and lay the first strand of a newly formed section into the groove along the outer or exposed face ofthe first die member. The forming face of the first bending tool is in effect a continuation of the exposed forming surface of the first die member, so that as the second bending tool 22, comes in from the reverse direction on an arc intersecting the arc of travel of the first tool, the second strand of wire will then be lapped over the back or outer face of the first bending tool to complete the forming operation. The reciprocating and swinging forming tools 20 and 22 instead of opening up in the reversed order indicated, may both slide outwardly substantially simultaneously and substantially parallel with the strands which they have just formed. This is permissible for the second bending finger 22, by the control exercised by the cam 14, and such movement is also possible for the first bending tool 20, by the cam edge of that tool leaving the roll 85. This straight outward sliding movement of the first tool is also governed in the illustration by the overlying portion at 59, of the second tool which serves as a confining guide during such outward sliding movement of the first tool.

The dies I9, 23, may start opening substantially simultaneously with the opening action of the bending tools. During such opening movements the formed stock is retained in position by the wire receiving grooves or channels sliding outwardly over the parallel strands of formed product and this control may be maintained while the feed slide 24 is being retracted from beneath the same and up to the moment when the clamp 25 or 26, if the latter be used, comes down to grip the work on the slide.

These operations are effected smoothly and rapidly, producing the desired accurate product at low cost. The forming operations are accomplished without injuring or straining the stock, the bending tools approaching from opposite directions and working sequentially on intersecting arcs having the effect simply of folding the stock first in one direction and then in the opposite direction, around forming surfaces which at the time are stationary. These actions are simple and free of any abrupt changes of movement so that the power factor is low and the machine operates quietly.

What is claimed is:

1. A forming machine of the character disclosed, comprising in combination, cooperating dies for holding formed strip stock attached to a supply length of stock and one having an outer face for partial formation of an attached portion of the stock thereover, a tool provided with a companion forming face and having a movement to carry the attached portion of stock about said outer forming face of the die, said forming tool having an outer forming face in continuation of the opposed forming face of said die and a second sequentially acting tool provided with a companion forming face and having a movement opposite that of said first forming tool to carry a successive portion of the extending stock about said continuation forming face of said first tool.

2. A combination as'i'n claim 1, in which said forming surfaces are composed in part of the mating portions of stock receiving grooves in the opposed edge portions of said members and in which/said grooves are closed by a feed slide in cooperative relation to all said members.

3. A construction as in claim 1, in which said dies and forming tools have companion faces all in substantially the same plane and in which said members have stock receiving grooves about their edges at said plane and a member having a substantially plane surface disposed to provide a closure to said stock receiving grooves.

4. A combination as in claim 1, with mechanism for relatively opening and closing said dies and for advancing and retracting said forming tools and intermittently operating feed slide mechanism for gripping and advancing the formed stool; when said dies and forming tools are retracted.

5. A combination as in claim 1, including means for advancing the forming tools in arcuate paths and for retracting same in substantially parallel relation.

6. A combination as in claim 1, including means for effecting retractive movements of said forming tools and in which the second forming tool has an overlying portion for confining and guiding the first forming tool in the retractive movements of the tools.

'7. The construction of claim 1, in which said forming tools approach from opposite sides of the stock line and have sequential movements on intersecting arcs to fold the stock first in one and then in the opposite direction and means for imparting said sequential arcuate movements to said forming tools and for then retracting said forming tools along substantially parallel lines.

8. The combination of claim 1, in which said forming tools engage and retain their engagement with the stock at the exact points of bend therein.

9. A combination as in claim 1, in which the dies are mounted on oppositely reciprocating slides, the forming tools are pivotally mounted on op-' positely working slides at one side of the die slides and in which means ape provided for positively shifting the forming tools on their pivotal mountings toward said die slides in the reciprocation of said forming tool slides.

10. A combination as in claim 1, in which the dies are mounted on oppositely reciprocating slides, the forming tools are pivotally mounted on oppositely working slides at one side of the die slides and in which means are provided for shifting the forming tools on their pivotal mountings in the reciprocation of said forming tool slides and a reciprocating feed slide operating at an angle between the opposed die and forming tool slides.

11. A forming machine, comprising in combination, cooperating members for holding stock material with part of such stock protruding from between the same, a forming tool having a swinging movement toward said holding members for folding a portion of such protruding stock over the outer face of one of said members and a sequentially acting forming tool having a swinging movement opposite that of said first forming tool and in a direction toward said first forming tool for then folding the successive portion of said protruding stock in reverse direction'about the exposed face of said first forming tool.

12. A combination as in claim 11, including mechanism for efiecting approach and separation of said holding members and forming tools'and feed mechanism for intermittently advancing the formed stock between said holding members in time with the separation of said members.

13. A forming machine, comprising opposed reciprocating slides, cooperating holding dies on said slides, opposed reciprocating slides at one side of said die slides, stock forming tools pivotally mounted on said second slides and cam mechanism for shifting said forming tools on their pivotal mountings in the reciprocating movements of the slides carrying the same.

14. A forming machine, comprising opposed reciprocating slides, cooperating holding dies on said slides, opposed reciprocating slides at one side of said die slides, stock forming tools pivotally mounted on said second slides, cam mechanism for shifting said forming tools on their pivotal mountings in the reciprocating movements of the slides carrying the same, a feed slide operating beneath said first mentioned slides at an angle to the movement of the same, a clamp on said feed slide for engaging the work at a point adjacent said dies and means for efi'ecting the lifting and lowering of said work engaging clamp in timed relation with the movement of said dies and forming tools.

15. A machine for forming strip stock in reversely facing bends connected by substantially parallel transverse strands, comprising transversely acting dies reciprocating in line with said transverse strands to alternately grip and release the same, one of said dies having substantially parallel inner and outer faces, a former for folding stock over the parallel outer face of said die and provided itself with a substantially parallel outer face, a second former having a movement reverse to the movement of the first former for folding the stock over said parallel outer face of the first former and mechanism for carrying said formers inwardly in sequence in intersecting generally arcua'te paths and for retracting said formers in substantial parallelism with the substantially parallel strands formed thereby.

16. In combination, a horizontally reciprocat ing feed slide having a plane upper surface, opposed sequentially acting formers operating over said plane upper surface ofsaid feed slide, co-

acting dies for the formed stock operating in opposition over said plane upper surface of the feed slide and means for actuating said feed slide, formers and dies in definite timed relation.

17. In combination, a horizontally acting feed slide, a guide for formed stock at the end of said feed slide, a detent for the formed stock on the end of said feed slide at the entrance to said guide and means operating over said feed slide to form strip stock in zig-zag formation in position to enter said guide.

18. In combination, a feed slide having a plane upper surface and a strip guiding throat in line with said surface, formers at opposite sides of said feed slide and operating in reverse directions over said plane upper surface of the feed slide and holding members for the formed stock operating in reverse directions over the plane surface of the feed slide in advance of said formers.

19. In a forming machine, a feed slide, a stock ward movement of the slide mounting the same,

a link connected with the other forming tool, cam means for operating said link to advance said tool over the first forming tool in the inward movement of the slide mounting said second forming tool, slides reciprocating transversely in opposite directions at oppositesides of said feed slide in advance of the forming tool slides, dies carried by 'said latter advance position slides shaped to engage the formed stock and to cooperate with the first former in imparting the desired form to the stock and means for reciproeating all said slides in timed relation.

21. A machine for forming zig-zag bends in previously straight wire stock and comprising alternately operating swinging forming fingers successively engaging the stock from opposite sides of the same on intersecting arcs and in overlapping relation and having stock forming faces to bend the stock alternately in reverse relations and to leave the stock between the bends in its original straight condition and operating means for swinging said forming fingers together into said overlapping relation and for then relatively separating the same on substantially straight line movements to clear said straight lengths of wire thus laid between said swinging forming fingers.

22. A forming machine "of the character disclosed, comprising in combination opposed companion dies for holding between them formed strip stock, a forming tool for cooperating with one of said dies, a second forming tool for cooperating with said first forming tool, said holding dies and forming tools having mating stock receiving grooves in their opposed edge portions and all in a common plane and a member having a plane surface disposed to form a closure to said stock receiving grooves and said member having a movement parallel to said plane surface and said dies and forming tools having movements parallel to said plane surface, whereby said member serves as a closure to said stock receiving grooves in the edges of the dies and forming tools in all positions of said member and in all positions of said dies and tools,

23. In a machine of the character set forth, the combination of stock forming tools, oppositely acting slides on which said tools are pivotally mounted, a relatively stationary abutment engageable by one of said tools to shift the same laterally with respect to the slide on which it is mounted, the other forming tool being constructed and operated to overlap said first forming tool in the laterally displaced position of the same, a link connected with said second forming tool and power means operating said link to positively force the second forming tool against the first forming tool and operating means for approaching and separating the slides supporting said forming tools.

DAVID L. BROWN.

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