US3690533A

US3690533A - Feeding apparatus for wire and like elongated material

Info

Publication number: US3690533A
Application number: US158694A
Authority: US
Inventors: Otto Bihler
Original assignee: Otto Bihler KG
Current assignee: Otto Bihler KG
Priority date: 1970-07-08
Filing date: 1971-07-01
Publication date: 1972-09-12
Anticipated expiration: 1989-09-12
Also published as: FR2101612A5; DE2033940A1; JPS5248386B1

Abstract

Wire or like elongated material is fed forward in uniform increments by jaws mounted on a slide which is reciprocated in the direction of wire elongation by a crank drive. The jaws are opened and closed in synchronization with the slide movement by an operating member longitudinally slidable in the hollow connecting rod of the crank drive and carrying a cam follower which engages a radial cam fixed on the crank pin of the drive. Movement of the operating member is transmitted to one of the jaws by a wedge-shaped cam on the operating member engaging a cam follower on the movable jaw.

Description

United States Patent Bihler [54] FEEDING APPARATUS FOR WIRE AND LIKE ELONGATED MATERIAL [72] Inventor:

many

[73] Assignee: Otto Bihler KG, I-Ialblech-Fussen, Germany [22] Filed: July 1, 1971 [2]] Appl. No.: 158,694

[30] Foreign Application Priority Data Otto Bihler, I-lalblech-Fussen, Ger- 7 Sept. 12, 1972 3,486,676 12/1969 Bruns ..226/ 165 X Primary Examiner-Allen N. Knowles Attorney-Kelman and Berman [5 7] ABSTRACT Wire or like elongated material is fed forward in uniform increments by jaws mounted on a slide which is reciprocated in the direction of wire elongation by a crank drive. The jaws are opened and closed in synchronization with the slide movement by an operating member longitudinally slidable in the hollow connecting rod of the crank drive and carrying a cam follower which engages a radial cam fixed on the crank pin of the drive. Movement of the operating member is transmitted to one of the jaws by a wedgeshaped cam on the operating member engaging a cam follower on the movable jaw.

9 Claims, 2 Drawing Figures PATENTEDSEP 12 1912 saw 1 or 2 INVEITGR Ofi'o 3/h/u BY WM M M,

AGENTS PATENTEDSE 2 I972 3.690.533

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2 or 2 INVE NTOR Of /'0 75/6 1 FEEDING APPARATUS FOR WIRE AND LIKE ELONGATED MATERIAL This invention is concerned with feeding apparatus for wire and like elongated, and normally endless, material which is advanced in small, equal increments toward a tool or the like.

It is known to provide such a feeding apparatus with a slide guided in the direction of material elongation and reciprocated by a suitable drive arrangement. Jaws on the slide are closed to engage the material while the slide moves in one direction and release the material during opposite movement of the slide. The jaws are operated in synchronization with the slide movement.

The force required for closing the jaws is relatively high, and is transmitted tothe slide in the known devices in such a manner as to increase the contact pressure between the slide and the guides which hold the slide in the desired path during its reciprocating movement. Wear of the engaged guiding surfaces is an important factor in determining the useful life of the known feeding arrangements.

A primary object of this invention is the provision of a feeding apparatus of the type described which is free from the shortcomings of the known devices and has a long and troublefree life.

Other features, additional objects, .and many of the attendant advantages of this invention will readily become apparent from the following detailed description of a preferred embodiment when considered in connection with the appended drawing in which:

FIG. 1 shows a feeding apparatus of the invention in top plan view; and

FIG. 2 illustrates the apparatus of FIG. 1 in sideelevational section on its vertical plane of symmetry.

Referring now to the drawing in detail, there is seena slide I mounted on two round guide bars 41, 42. The moving mechanism which reciprocates the slide 1 on the bars 41, 42, as indicated by a double arrow in FIG. 1, includes a circular disc 12 mounted on an upright drive shaft 16 which is turned at uniform speed counterclockwise, as viewed in FIG. 1, during operation of the apparatus. The disc 12 functions as the web of a crank drive also including a crank pin 18 whose axis is parallel to and offset from the axis of the drive shaft 16.

A tubular elongated connecting rod 29 is'provided with a fixed bottom end bearing 9 which engages the pin 18 for angular movement of the rod 29 about the axis of the pin 18. A rubber sleeve 10 is interposed between the bearing shell and the body of the bottom end bearing 9 to permit very limited movement of the crank pin 18 while the connecting rod 29 stands still.

The top end of the connecting rod 29 is secured to the slide 1 by a hinge arrangement which permits the rod 29 to pivot about yet another axis parallel to the afore-mentioned axes of the shaft 16 and the crank pin 18. The hinge arrangement includes a bracket 6 which is secured to the slide 1 by a hinge pin 11 and may swing in an opening 20 of the slide 1 while threadedly attached to the connecting rod 29.

In the illustrated condition of the apparatus, the path of the slide 1, which is determined by the guide bars 41, 42 and rectilinear, is parallel to a line or plane drawn through the axes of the shaft 16, the crank pin 18, and the hinge pin 1 1.

A fixed clamping jaw 38 on the slide 1 cooperates with a movable jaw 32 pivotally mounted on the slide 1 to define a passage 2 whose width is narrowest in the illustrated position of the apparatusand slightly narrower than the thickness of the material that it is desired to feed, the jaws illustrated being particularly suitable for flat wire or strip of metal or other slightly resilient stock.

The operating mechanism which holds the jaw 32 in the illustrated position closely adjacent the fixed jaw 38 while the slide moves away from the-disc '12, and holds the jaw 32 sufficiently remote fromthe jaw 38 during movement of the slide in the opposite direction to release the material being fed includes a radial cam 23 fixedly mounted on the crank web or disc 12 in coaxial relationship to the crank pin 18 by a flanged sleeve 21 fixed on the crank pin 18.

An elongated, round, operating bar 28 is longitudinally slidably received in the bore of the tubular connecting rod 29. A fork 37 fixedly attached to one terminal portion of the operating bar 28 carries a cam follower roller 24 which is held in rolling contact with the cam face of the cam 23 by a helical compression spring 27 coiled about the afore-mentioned terminal portion of the bar 28 and abuttingly interposed between respective surfaces of the bottom end bearing 9 and the fork 37. It will be appreciated that the bottom end bearing 9 and the top end of the connecting rod 29 are on a common horizontal level in the illustrated apparatus, and that the terms bottom end and top en are merely chosen by analogy to automotive applications to designate the ends of a connecting rod near and remote from a crank pin respectively.

The other terminal portion of the operating bar 28 carries a wedge-shaped cam 4 which slides on a guide face of the bracket 6. The underside of the movable jaw 32 is provided with a recess 39 which conforrningly receives a bearing ball 31. The downward movement of the ball 31 out of the recess 39 is limited by a metal strip 33 provided with an opening 5 only slightly smaller than the largest cross section of the ball 31, but sufiicient to permit engagement of the ball with the face of the cam 4 obliquely inclined relative to the direction of elongation of the bar 28 in all operative positions of the cam. A strong leaf spring 30 has one end fixedly attached to the bracket 6 while the free end abuts against the jaw 32 and biases the jaw away from the fixed jaw 38, thereby holding the ball 31 engaged with the earn 4.

The crank pin 18 is fixedly mounted on a slide 40 received in dovetail engagement between two segmentshaped guide plates 15. The guide plates are fastened to the disc 12 by clamping screws 35, 36 which pass through arcuate slots in the guide plates and therefore permit limited angular adjustment of the guide plates. The position of the slide 40 in the dovetail slot extending along a diameter of the disc 12 between the guide plates 15 is determined by a threaded spindle l7 engaging a threaded bore in the slide 40 and rotatably secured against axial movement in a yoke 19 which connects the guide plates 15 at one end of the dovetail slot. When the spindle 17 is turned, the axis of the crank pin 18 is shifted toward or away from the axis of the drive shaft 16 to vary the throw of the crank drive, and thereby to vary the length of the wire increments fed during each cycle of reciprocating movement of the crank l. v

The cam 23, as is best seen in FIG. 1, has a cam face which extends in a closed loop about the axis of the crank pin 18. The cam face has two almost semicircular sections of different radius connected by steep, short flanks.

As shown in FIG. 1, the slide 1 is in its end position most remote from the axis of the drive shaft 16, and the cam follower roller 24 holds the operating bar 28 against the force of the springs 27 and 30 (FIG. 2) in such a position that the ball 31 engages the highest point on theoblique face of the cam 4, thereby holding the movable jaw 32 closely adjacent the jaw 38. The

passage 2 is at its smallest cross section. The cam follower 24. abuts against the face portion of the cam 23 of larger radius.

When the shaft 16 turns the disc 12 counterclockwise from the position shown in FIG. 1, the cam follower roller 24 drops to the face portion of the cam 23 of smaller radius, thebar 28 is moved toward the shaft 16 by the combined effects of the

springs

27 and 30, the ball 31 rolls downward along the oblique face of the earn 4 and thereby permits the spring30 to pivot the jaw 32 away from the jaw 38. During continued rotation of the shaft 16 and of the attached disc 12, the connecting rod 29 pulls the slide 1 toward the shaft 16, and the opened jaws 32, 38 slide along the non-illustrated, releasedflat wire or strip received in the passage 2. When the disc 12 has turned through an angle of 180, the slide 1 is nearest the shaft 16, the cam follower roller 24 returns to the cam face portion of greater radius on the cam 23, and the jaws 32, 38 are closed about the non-illustrated wire or strip. During subsequent return of the apparatus to the illustrated position, the wire or strip is taken along and fed forward, that is, to the left as viewed in the drawing.

Because the axes of the drive shaft 16, the crank pin 18, and the hinge pin 11 are aligned in the direction of slide movement on the guide bars 41, 42, the slide 1 moves in its rectilinear path only to a minimal extent while the disc 12 moves into and out of the position shown in the drawing. The jaws .32, 38 are being opened and closed during the feeding cycle .while the slide 1 almost stands still. If so desired, stops (not illustrated) may be provided to engage the slide 1 immediately before it would normally reach the end positions of its stroke of which only one is seen in the drawing. The shortening of the slide stroke, without any other changes in the apparatus, results in compression of the rubber sleeve 10, and the compressibility of the sleeve determines the length by which the stroke of the slide 1 may be shortened. When the slide 1 engages one of the non-illustrated stops, it stands still while the crank pin 18 continues turning about the axis of the shaft 16, and the cam follower 24 travels along the face of the cam 23. The jaws 32, 38 thus are opened and closed whilethe slide 1 is stationary, a mode of operation which is often desirable.

While the sleeve 10 hasbeen shown to be interposed between the connecting rod 29 and the crank pin 18, it may obviously be provided anywhere else in the motion transmitting train connecting the crank web 12 and the slide 1 and constituted essentially by the crank pin 18, the connecting rod 29, and the hinge arrangement including the bracket 6 and the hinge pin 11, without significantly affecting its operation.

Other modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. A feeding apparatus for wire and like elongated material comprising, in combination:

a. a slide member;

b. guide means guiding said slide member in a path;

c. moving means for reciprocating said slide member in said path between two terminal positions, said moving means including 1. a crank web member,

2. drive means for rotating said crank web member about a first axis,

3. a crank pin member on said crank web member, said crank pin member having a second axis spaced from said first axis,

4. a tubular, elongated connecting rod having one end portion engaging said crank pin member for angular movement about said second axis, and

5. hinge means securing the other end portion of said connecting rod to said slide member for pivoting movement about a third axis;

. two clamping jaw members mounted on said slide member; and I operating means for holding one of said jaw members adjacent the other jaw member while said slide member moves in one direction in said path thereof, and for holding said one jaw member remote from said other jaw member while said slide member moves in the opposite direction, said operating means including 1. a cam member mounted on said crank web member,

2. an elongated operating member longitudinally movable in said connecting rod,

3. cam follower means operatively connected to one longitudinally terminal portion of said operating member and. engaging said cam member, and

4. connecting means connecting the other terminal portion of said operating member to said one jaw member.

2. An apparatus as set forth in claim 1, wherein said path is substantially rectilinear and parallel to a line through said second and third axes when said slide member is in one of said terminal positions.

3. An apparatus as set forth in claim 1, wherein said cam member has a cam face extending in a closed loop, two portions of said cam face being substantially semicircular about said second axis and of different radius.

4. An apparatus as set forth in claim 3, wherein said cam follower means include a cam follower member mounted on said one terminal portion and yieldably resilient means biasing said cam follower member toward engagement with said cam face.

5. An apparatus as set forth in claim 3, further comprising adjusting means for shifting said crank pin member relative to said crank web member and for thereby varying the spacing of saidfirst and second axes.

6. An apparatus as set forth in claim 5, wherein said crank pin member, said connecting rod, and said hinge means jointly constitute members of a motion transmitting train connecting said crank web member to said slide member, said train further including a resilient buffer interposed between two members of said train for permitting limited movement of said crank web member while said slide member stands still.

7. An apparatus as set forth in claim 1, wherein said one jaw member is movably mounted on said slide member, the other jaw member being fixedly mounted on said slide member.

8. An apparatus as set forth in claim 7, wherein said

Claims

1. A feeding apparatus for wire and like elongated material comprising, in combination: a. a slide member; b. guide means guiding said slide member in a path; c. moving means for reciprocating said slide member in said path between two terminal positions, said moving means including 1. a crank web member, 2. drive means for rotating said crank web member about a first axis, 3. a crank pin member on said crank web member, said crank pin member having a second axis spaced from said first axis, 4. a tubular, elongated connecting rOd having one end portion engaging said crank pin member for angular movement about said second axis, and 5. hinge means securing the other end portion of said connecting rod to said slide member for pivoting movement about a third axis; d. two clamping jaw members mounted on said slide member; and e. operating means for holding one of said jaw members adjacent the other jaw member while said slide member moves in one direction in said path thereof, and for holding said one jaw member remote from said other jaw member while said slide member moves in the opposite direction, said operating means including 1. a cam member mounted on said crank web member, 2. an elongated operating member longitudinally movable in said connecting rod, 3. cam follower means operatively connected to one longitudinally terminal portion of said operating member and engaging said cam member, and 4. connecting means connecting the other terminal portion of said operating member to said one jaw member.

2. drive means for rotating said crank web member about a first axis,

2. an elongated operating member longitudinally movable in said connecting rod,

3. cam follower means operatively connected to one longitudinally terminal portion of said operating member and engaging said cam member, and

5. An apparatus as set forth in claim 3, further comprising adjusting means for shifting said crank pin member relative to said crank web member and for thereby varying the spacing of said first and second axes.

5. hinge means securing the other end portion of said connecting rod to said slide member for pivoting movement about a third axis; d. two clamping jaw members mounted on said slide member; and e. operating means for holding one of said jaw members adjacent the other jaw member while said slide member moves in one direction in said path thereof, and for holding said one jaw member remote from said other jaw member while said slide member moves in the opposite direction, said operating means including

8. An apparatus as set forth in claim 7, wherein said connecting means include a cam member having a cam face obliquely inclined relative to the direction of elongation of said operating member and mounted on said other terminal portion, said one jaw member being mounted on said slide member for pivoting movement, and cam follower means on said one jaw member movably engaging said obliquely inclined cam face.

9. An apparatus as set forth in claim 8, wherein said connecting means further include yieldably resilient means biasing said one jaw member away from said other jaw member.