US3581781A

US3581781A - Wire forming apparatus

Info

Publication number: US3581781A
Application number: US820812A
Authority: US
Inventors: Alton O Demlow
Original assignee: Demlow and Son
Current assignee: Demlow and Son
Priority date: 1969-05-01
Filing date: 1969-05-01
Publication date: 1971-06-01
Anticipated expiration: 1988-06-01

Abstract

A wire forming apparatus for use on a continuous length of generally flat sinuously bent wire. Drive mechanism including a motor driven star wheel gear discharges the wire onto one end of a longitudinally ending guide track. An adjustment device is provided for manually rotating or adjusting the rotative position of the star wheel gear to increase or decrease the tension force on the wire. A vertically movable crowning block is positioned over the star wheel gear. A longitudinally extending arm is positioned above a portion of the guide track. If the wire moving along the guide track reaches a predetermined vertical elevation above the guide track, movement of the arm operatively stops the drive mechanism. Shearing mechanism for cutting the wire is positioned adjacent the other end of the guide track and control mechanism is provided for actuating the shearing mechanism at predetermined intervals.

Description

United States Patent [72] inventor Alton 0. Demlow Adrian, Mich.

[21] Appl. No. 820.812

[22] Filed May 1,1969

[45] Patented June 1, 1971 [73] Assignee Demlow & Son Clayton, Mich.

[54] WIRE FORMING APPARATUS 11 Claims, 10 Drawing Figs.

Primary Examiner- Lowell A. Larson Attorney-Owen and Owen ABSTRACT: A wire forming apparatus for use on a continuous length of generally flat sinuously bent wire. Drive mechanism including a motor driven star wheel gear discharges the wire onto one end of a longitudinally ending guide track. An adjustment device is provided for manually rotating or adjusting the rotative position of the star wheel gear to increase or decrease the tension force on the wire. A vertically movable crowning block is positioned over the star wheel gear A longitudinally extending arm is positioned above a portion of the guide track. if the wire moving along the guide track reaches a predetermined vertical elevation above the guide track, movement of the arm operatively stops the drive mechanism. Shearing mechanism for cutting the wire is positioned adjacent the other end of the guide track and control mechanism is provided for actuating the shearing mechanism at predetermined intervals,

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WIRE FORMING APPARATUS BACKGROUND OF THE INVENTION Attempts have been made in the past to provide a satisfactory wire forming apparatus for the forming of uniform lengths of sinuously bent wire which is used, for example, as springs in automobile seats. U.S. Pat. No. 2,830,646 discloses one such prior art device.

Many of the prior art devices were suitable for use upon wire ofa single gauge and in situations where the radius of curvature of a length of the sinuously bent wire remained constant.

However, in the prior art devices problems arose when the wire gauge or the radius of curvature was changed. When this changeover was made, jamming of the prior art machines sometimes occurred resulting in production down time.

SUMMARY OF THE INVENTION The present invention solves the major problems of the prior art machines by providing a wire forming apparatus which is easily adjusted to accommodate sinuously bent wire of different wire gauges and is also readily adjustable to change the radius ofcurvature ofthe wire.

A wire forming apparatus, according to the present invention, is suitable for use on a continuous length of generally flat sinuously bent wire, such bent wire having a plurality of generally parallel center portions joined together by semicircular end sections. The apparatus includes drive means for advancing the wire at a predetermined and constant rate. A longitudinally extending guide track receives and guides the wire as it is discharged from the drive means. Adjusting means are operatively connected to the drive means and are effective to place a predetermined tension force on a length of the wire. Crowning means are positioned adjacent the drive means and are effective to bend a portion of the generally flat wire into an arcuate configuration ofa predetermined radius.

The apparatus also includes safety means mounted on the guide track for stopping the drive means when the wire reaches a predetermined vertical elevation above the guide track. Shearing means adjacent the guide track are provided to cut the wire into predetermined lengths and control means are provided for actuating the shearing means at predetermined intervals.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a side view in elevation of a wire forming apparatus, according to the present invention, being used in tandem with a wire bending machine which does not form a part of the present invention;

FIG. 2 is a vertical sectional view, shown on an enlarged scale, taken along the line 2-2 of FIG. 1;

FIG. 3 is a vertical sectional view taken along the line 3-3 of FIG. 2;

FIG. 4 is a fragmentary, top view of a wire forming apparatus, according to the present invention;

FIG. 5 is a fragmentary, side elevational view of the apparatus shown in FIG. 4;

FIG. 6 is an enlarged top view, of a portion of the apparatus shown in FIG. 4, showing in particular a safety means;

FIG. 7 is a vertical, sectional view taken along the line 7-7 of FIG. 6;

FIG. 8 is a fragmentary, elevational view ofa portion of the apparatus shown in FIG. 5, and showing in particular control means for actuating the shearing means;

FIG. 9 is a fragmentary, vertical sectional view taken along the line 9-9 of FIG. 8; and

FIG. 10 is a diagrammatic view of a portion of the electrical and mechanical control means for actuating the shearing means.

DESCRIPTION OF THE PREFERRED EMBODIMENT Apparatus for forming sinuously bent wire, according to the present invention, is generally indicated in FIG. 1 by the reference number 20. A wire bending machine is generally indicated by the reference number 21. The wire bending machine 21 is not a part of the present invention. Rather, the wire forming apparatus 20, according to the present invention, is normally used in tandem with the wire bending machine 21. However, in the present embodiment, a common drive mechanism is utilized. A motor 22 is mounted within a housing 23 of the wire bending machine 21. A drive chain 24 is operatively connected to the motor 22 by an intermediate drive chain 25 and an intermediate pulley 26.

Wire 27 is withdrawn from a coil 28 positioned on a holder 29 and is fed through the wire bending machine 21. Referring to FIG. 4, the machine 21 bends the wire 27 into a continuous length of generally flat sinuously bent wire. The wire 27, after being bent, has a plurality of generally parallel central portions 30 which are joined together by semicircular end sections 31.

The wire forming apparatus 20, according to the present invention, is capable of forming and cutting sinuously bent wire of varying wire gauges. For example, the present embodiment of the apparatus 20 is suitable for use upon wire of between thirteen gauge and nine gauge.

The wire forming apparatus 20 includes a floor mounted base frame 33 having a rearwardly extending frame member 34 which in the present embodiment extends between the floor mounted base frame 33 and the wire bending machine 21. Referring to FIG. 2, a support frame 35 having vertical, spaced sidewalls 36 and a top member 37 is mounted on the rearwardly extending frame member 34.

Drive means for advancing the sinuously bent wire 27 at a predetermined rate includes the motor 22, the intermediate drive mechanism including the

drive chains

24 and 25, the pulley 26, and a horizontal shaft 38 which is journaled in bearings 39 mounted in the sidewalls 36 of the support frame 35. A star wheel gear 40 is positioned between the sidewalls 36 and is keyed to the shaft 38. The star wheel gear 40 has a plurality of circumferentially positioned teeth 41 which are effective to drive the sinuously bent wire 27. Referring to FIG. 5, the teeth 41 engage successive ones of the parallel central portions 30 and move the sinuously bent wire 27 at a predetermined and essentially constant rate of speed.

Referring in particular to FIG. 2, the drive means also includes a drive ring 42 which is connected to a drive gear 43. The drive chain 24 extends around and drives the drive gear 43.

An important feature of the present invention is an adjusting means which is operatively connected to the drive means and which is effective to place a predetermined tension force on a portion of the sinuously bent wire. Referring to FIG. 4, sometimes the central portions 30 of the sinuously bent wire 27 are not parallel. The adjusting means allows the operator to either increase or decrease the tension in the sinuously bent wire between the star wheel gear 40 and the wire bending machine 21 ro place the central portions 30 of the sinuously bent wire 27 into a parallel relationship.

The adjusting means includes a plurality of serrated teeth 44 located on the outer periphery of the drive ring 42. The drive ring 4 is rotatably mounted on a bushing 45 which in turn is mounted on the shaft 38. The drive ring 42 and the drive gear 43 also define a plurality of openings 46 which are positioned parallel to the shaft 38 and which extend completely through the drive ring 42 and the drive gear 43. A driven ring 47 is rotatably mounted on the shaft 38 adjacent the drive ring 42. The driven ring 47 has a plurality of teeth 48 on its outer periphery suitable for mating with the teeth 44 of the drive ring 42. A back plate 49 is keyed to the shaft 38 and is held adjacent one end of the shaft 38 by a washer 50 and nut 51. However, the back plate 49 is longitudinally movable along the shaft 38 in the direction opposed to the nut 51. Movement of the back plate 49 in this direction is resisted by a plurality of radially spaced springs 52 which are mounted between the driven ring 47 and the back plate 49. Drive pins 53 (see FIG. 3) extend between the driven ring 47 and the back plate 49. A handwheel 54 is mounted on the opposite end of the shaft 38 by a washer 55 and lock nut 56.

Clutch means are provided for separating the drive ring 42 and the driven ring 47 to enable the shaft 38 to be rotated to adjust the rotative position of the star wheel gear 40. This adjusts or changes the tension on the sinuously bent wire which extends between the star wheel gear 40 and the wire bending machine 21.

In the present embodiment, the clutch means includes a clutch plate 59 which is rotatably mounted on the shaft 38 adjacent the drive ring 42. The clutch plate 59 is in an opposed relationship to the driven ring 47. A plurality of clutch pins 60 extend between the clutch plate 59 and the driven ring 47. The clutch pins 60 extend through the openings 46 which are provided in the drive ring 42 and the drive gear 43.

A handle 61 is pivotally mounted on projections 62 which extend outwardly from one of the sidewalls 36 of the support frame 35. In the present embodiment, the handle 61 has a bifurcated lower end 63 which extends downwardly on both sides ofthe shaft 38.

During a normal operation, the motor 22 is actuated and drives the drive chain 24 through the intermediate drive mechanism. The drive chain 24 directly drives the drive gear 43 and the connected drive ring 42. The drive ring 42 transfers force to the driven ring 47 by means of the mating

serrated teeth

44 and 48 located on the respective members. The drive pins 53 transfer the force from the driven ring 47 to the back plate 49 which is keyed to the shaft 38. Rotation of the shaft 38 rotates the star wheel gear 40 which, acting through the teeth 41, drives the sinuously bent wire at a predetermined rate of speed.

To adjust the tension in the wire, the motor 22 is deenergized stopping rotation of the shaft 38. The clutch handle 61 is moved upwardly moving the clutch plate 59 to the left (see FIG. 2) against the clutch pins 60. The ends of the clutch pins 60 engage a bearing washer 64 and move the driven ring 47 to the left against the bias of the springs 52. This disengages the meshing relationship of the drive ring 42 and the driven ring 47. The disengagement of the driving or meshing relationship between the drive ring 42 and the driven ring 47 allows the handwheel 54 to be rotated to either advance or retard the rotative position of the star wheel gear 40. This either increases or decreases the tension force on the wire 27. When the handle 61 is released the bifurcated lower portion 63 moves to its rest position adjacent the sidewall 36 of the support frame 35 and the springs 52 located between the back plate 49 and the driven ring 47 urge the driven ring 47 into a complementary or meshing relationship with the drive ring 42.

Referring to FIG. 5, a longitudinally extending guide track 66 has one end pivotally mounted on projections 67 which extend outwardly from the support frame 35. The guide track 66 includes a generally flat bottom 68 and a pair of opposed

parallel sidewalls

69 and 70. Referring to FIG. 4, the free end ofthe guide track 66 terminates in a plurality of fingers 71.

Referring to FIGS. 1, 5, and 9, a support bracket 73 extends upwardly from the floor mounted base frame 33 and mounts a pair of vertical support walls 74 and 75 (see FIG. 9). The vertical support wall 74 defines a slot 76 which receives a horizontally extending shaft housing 77. The housing 77 journals an idler shaft 78 having a star wheel gear 79 keyed to one end and a chain gear 80 fixed to its other end. Referring to FIG. 9, the housing 77 mounts a guide track extension 81 which includes a pair of fingers 82. The fingers 82 mate with the fingers 71 at the end of the guide track 66. The guide track extension 81 has a pair of inwardly directed lips 83 which define a guideway 84 for the passage of the sinuously bent wire 27. As the wire 27 passes through the guideway 84 and along the guide track extension 81, it engages the star wheel gear 79 and causes the gear to rotate. This in turn rotates the idler shaft 78 and the chain gear which is a portion of a control means which will be described in detail below.

Referring to FIG. 1, a punch press, generally indicated by the reference number 85 is positioned adjacent the guide track 66 and the guide track extension 81 and is used to cut the sinuously bent wire 27 into predetermined lengths. Referring to FIG. 4, the punch press 85 has a cutoff die 86 which includes a lower anvil member 87 and an upper vertically movable shear member 88. A plurality of guide rods 89 mate with complementary openings 90 defined in the lower member 87 to align and hold the length of the wire 27in its proper cutoff position (see FIG. 4).

Referring to FIGS. 4, 5, and 7, crowning means are generally indicated by the reference number 92. In the present embodiment, the crowning means 92 includes an opening 93 (see FIG. 7) which is defined through the top member 37 of the support frame 35. An adjustment nut 94 is seated in the opening 93 and threadedly receives a vertically extending ad justment screw 95. A crowning block 96 having a contoured lower surface 97 depends from the lower end of the adjustment screw -95. As the sinuously bent wire travels around the star wheel gear 40 it is urged against the lower surface 97 of the crowning block 96. The crowning means 92, including the lower surface 97 of the crowning block 96, is effective to bend the wire into an arcuate shape ofa predetermined radius. This radius varies between a radius as short as 6 inches to a very large radius where the wire remains essentially flat.

An adjustment handle 98 is attached to the adjustment screw at a location above the top member 37 ofthe support frame 35. The adjustment handle 98 is effective to vertically move the adjustment screw 95 which in turn vertically moves the crowning block 96. Movement of the crowning block 96 varies the radius of the sinuously bent wire 27.

Referring to FIGS. 6 and 7, safety means are generally indicated by the reference number 100. The safety means 100 is mounted adjacent the guide track 66 and is effective to stop the drive means when the sinuously bent wire 27 reaches a predetermined vertical elevation above the guide track 66. In the present embodiment, the safety means 100 includes a longitudinally extending arm 101 which is fixed to a horizontal pivot rod 102. The rod 102 is mounted for rotation through the

sidewalls

69 and 70 of the guide track 66. A generally flat striker member 103 (see FIG. 4) is mounted on the outer end ofthe arm 101.

Referring to FIGS. 6 and 7, switching means generally indicated by the reference number 105 are mounted adjacent the sidewall 69 of the guide track 66. In the present embodiment, the switching means 105 includes a cam 106 which is fixed to the pivot rod 102. The cam 106 has a circular recess 107 in its periphery. A switch activating member 108 having an outer circular periphery complementary with the recess 107 is mounted for movement parallel to the guide track 66. The member 108 includes an outwardly extending striker post 109. A microswitch having a switch plunger 111 is mounted in a manner such that the movement of the post 109 engages the switch plunger 111 and activates the microswitch 110. The microswitch 110 is operatively connected to the motor 22. During normal operation, the striker member 103 rides above the sinuously bent wire 27 as it moves along the guide track 66. If for some reason the apparatus 20 jams and the wire 27 builds up in the guide track 66, the buildup of the wire will move the striker member 103 upwardly and this in turn will rotate the pivot rod 102. The cam 106 is rotated forcing the switch activating member 108 out of its position within the recess 107. This moves the switch activating member 108 to the left as shown in FIG. 7. When the striker member 103 has reached a predetermined vertical elevation above the bottom 68 of the guide track 66, the post 109 (see FIG. 6) has moved sufficiently to activate the switch plunger 111 and the microswitch 110. This deenergizes the motor 22. After the jam or malfunction is corrected, and the safety means 100 is returned to its normal operating position, wherein the switch activating member 108 is positioned within the cam recess 107, the motor circuit is closed and the wire bending and cutoff apparatus resumes normal operation.

Referring to FIG. 1, a pivot frame 114 has a lower end 115 pivotally connected to the floor mounted base frame 33. An upper end 116 of the pivot frame 114 (see FIG. 9) mounts the cylindrical housing 77 which in turn mounts the guide track extension 81 as described above.

The pivot frame 114 defines a vertically extending slot 118. An idler sprocket wheel assembly 119 is mounted for vertically adjustable movement along the slot 118. Referring to FIG. 1, the chain gear 80 and the wheel of the sprocket wheel assembly 119 mounts a measuring chain 120. The measuring chain 120 is sized in direct proportion to the desired length of the wire, for example, a wire length 121 (see FIG. 1). If the length of the wire is to be increased, links are added to the measuring chain 120 and if it is to be decreased, links are removed from the chain 120. Referring to FIG. 8, a lug 122 is mounted on the continuous measuring chain 120.

An arm 123 (see FIG. 8) extends from the upper end 116 of the pivot frame 114 and defines a generally horizontal slot 124. A bolt 125 operatively connects the arm 123 to the support bracket 73. When necessary, the bolt 125 is loosened and the pivot frame 114 is moved to adjust the position of the guide track extension 81. These adjustments are made to insure that the sinuously bent wire 27 is correctly positioned within the cutoff die 86, as shown in FIG. 4.

Referring to FIG. 8, a pawl mechanism 127 is mounted adjacent the arm 123. The pawl mechanism 127 includes a pawl 128 which is biased by a spring 129 to the right, as shown in FIG. 8. The pawl mechanism 127 also includes a solenoid assembly 130 having a plunger 131. A switch 132 having a switch finger 133 is spaced from the pawl mechanism 127. As the measuring chain 120 moves in its counterclockwise direction, the chain lug 122 engages the pawl 128. The chain continues its counterclockwise movement until the pawl 128 has been moved sufficiently to the left (see FIG. 8) to engage and activate the switch finger 133. At this time, movement of the continuous measuring chain 120 stops and the wire 27 is correctly positioned within the cutoff die 86.

Referring to FIG. 10, when the switch 132 is closed, it energizes a punch press solenoid 134 which is operatively connected to a switch 135 in an electrical circuit to a punch press motor 136. The punch press 85 is activated and the upper vertical movable member 88 of the cutoff die 86 descends to shear the wire 27 which is positioned within the lower anvil member 87 of the die 86. A cam member 138 of the punch press 85 rotates approximately 180 and activates a switch 139. When this occurs, the solenoid assembly 130 is activated (see FIG. 8), the plunger 13] descends and rocks the pawl 128 as indicated by the dashed lines in FIG. 8. This releases the lug 122 and the chain 120 begins to rotate. The spring 129 returns the pawl 128 to its rest position.

While the chain 120 is stopped, during the above-described punch press operation, the sinuously bent wire 27 within the guide track 66 backs up. However, it does not reach such a vertical elevation above the guide track 66 as to activate the safety means 100.

The above-described apparatus is capable of bending and shearing the sinuously bent wire at a rate in excess of 50 feet a minute.

What I claim is:

1. A wire forming apparatus, for use on a continuous length of generally flat sinuously bent wire, such bent wire having a plurality of generally parallel central portions joined together by semicircular end sections comprising, in combination, drive means for advancing such wire at a predetermined rate, a longitudinally extending guide track positioned adjacent said drive means for receiving and guiding the wire discharged from said drive means, adjusting means operatively connected to said drive means and effective to place a predetermined tension force on such wire, crowning means adjacent said drive means effective to bend a portion of such generally flat wire into an arcuate shape of a predetermined radius, safety means mounted on said guide track for stopping said drive means when such wire reaches a predetermined vertical elevation above said guide track, shearing means adjacent said guide track for cutting such wire into predetermined lengths, and control means adjacent said shearing means for actuating said shearing means at predetermined intervals.

2. A wire forming apparatus, according to claim 1, wherein said drive means includes a horizontal shaft rotatably mounted above said guide track, a star wheel gear mounted on said shaft, whereby such bent wire is pushed along said guide track by said star wheel gear, and motor means operatively connected to said shaft.

3. A wire forming apparatus, according to claim 2, wherein said adjusting means includes, a drive ring rotatably mounted on said shaft, said drive ring having a plurality of serrated teeth adjacent one periphery, a driven ring rotatably mounted on said shaft adjacent said drive ring, said driven ring having a plurality of teeth on one periphery suitable for mating with the teeth of said drive ring when in a drive position, a back plate fixably mounted on said shaft and spaced from said driven ring, a plurality of springs mounted between said back plate and said driven ring for urging the driven ring teeth into meshing relationship with the drive ring teeth, at least one drive pin extending between said driven ring and said back plate, and clutch means for separating said drive ring and said driven ring, whereby said shaft may be rotated to adjust the rotative position of said star wheel gear.

4. A wire forming apparatus, according to claim 3, including a handwheel mounted on said shaft for manually rotating said shaft.

5. A wire forming apparatus, according to claim 4, wherein said clutch means includes a clutch plate rotatably mounted on said shaft adjacent said drive ring and in opposed relation to said driven ring, a plurality of clutch pins operatively connected between said clutch plate and said driven ring, and a handle operatively connected to said clutch plate, whereby said handle is effective to move said clutch plate and disengage the meshing relationship of said drive ring and said driven ring.

6. A wire forming apparatus, according to claim 2, wherein a support frame is mounted at a first end of said guide track, said support frame having opposed parallel sidewalls and a top member extending between said sidewalls, said horizontal shaft extending through said sidewalls, said star wheel gear being positioned between said sidewalls, said crowning means comprising a vertically movable crowning block positioned above said star wheel gear, said crowning block having a contoured lower surface, an adjustment screw having its lower end attached to said crowning block and having an" upper portion operatively connected to said top member of said support frame, and means for vertically adjusting said crowning block.

7. A wire forming apparatus, according to claim 6, wherein said top member defines an opening therethrough and wherein said means for vertically adjusting said crowning block comprises an adjustment nut positioned in such opening, said nut threadedly receiving said adjustment screw and an adjustment handle mounted adjacent the upper end of said adjustment screw.

8. A wire forming apparatus, according to claim 2, wherein said safety means includes a longitudinally extending arm positioned above said guide track, a rod extending transversely across and above said guide track, said arm having a first end fixably mounted on said rod, a striker member mounted on the other end of said arm, and switching means mounted adjacent said rod effective to deenergize said motor means when said striker member is moved a predetermined vertical distance above said guide track.

9. A wire forming apparatus, according to claim 8, wherein said switching means includes a cam mounted on said rod, a switch activating member positioned adjacent said cam, and a switch positioned adjacent said switch activating member, said switch being operatively connected to said motor means, whereby when said striker member moves such predetermined vertical distance above said guide track the rotation of said rod and said cam moves said switch activating member activating said switch.

10. A wire forming apparatus, according to claim 1, wherein said shearing means includes a punch press mounted adjacent said guide track and wherein said control means includes a revolution of said continuous chain said lug engages said pawl which in turn activates said switching means.

11. A wire forming apparatus, according to claim 10, including a pivot frame mounted adjacent one end of said guide track, said one end ofsaid guide track terminating in a plurality of fingers, said pivot frame mounting a guide track extension having mating fingers complementary with said guide track fingers, said pivot frame having its lower end pivotally mounted and means for adjusting the upper end of said pivot member to change the spacing relationship of said complementary fingers.

Claims

6. A wire forming apparatus, according to claim 2, wherein a support frame is mounted at a first end of said guide track, said support frame having opposed parallel sidewalls and a top member extending between said sidewalls, said horizontal shaft extending through said sidewalls, said star wheel gear being positioned between said sidewalls, said crowning means comprising a vertically movable crowning block positioned above said star wheel gear, said crowning block having a contoured lower surface, an adjustment screw having its lower end attached to said crowning block and having an upper portion operatively connected to said top member of said support frame, and means for vertically adjusting said crowning block.

10. A wire forming apparatus, according to claim 1, wherein said shearing means includes a punch press mounted adjacent said guide track and wherein said control means includes a continuous chain of a predetermined length mounted adjacent said guide track, a lug mounted on said chain, means for moving said continuous chain in response to the movement of said wire along said guide track, a pawl mounted adjacent said continuous chain, switch means mounted adjacent said pawl effective to operate said shearing means, whereby during each revolution of said continuous chain said lug engages said pawl which in turn activates said switching means.

11. A wire forming apparatus, according to claim 10, including a pivot frame mounted adjacent one end of said guide track, said one end of said guide track terminating in a plurality of fingers, said pivot frame mounting a guide track extension having mating fingers complementary with said guide track fingers, said pivot frame having its lower end pivotally mounted and means for adjusting the upper end of said pivot member to change the spacing relationship of said complementary fingers.