US3662788A

US3662788A - Spring making machines and methods

Info

Publication number: US3662788A
Application number: US33271A
Authority: US
Inventors: Terence J L Clarke; Robert C Quarmby; Kenneth Dennis
Original assignee: Terence J L Clarke; Robert C Quarmby; Kenneth Dennis
Current assignee: Emhart Industries Inc
Priority date: 1970-04-30
Filing date: 1970-04-30
Publication date: 1972-05-16
Anticipated expiration: 1989-05-16

Abstract

The invention relates to machines and methods for use in forming attaching loops in generally longitudinal orientation at or from end portions of coil springs. A spring is supported by support means of a machine with an end portion to be looped projecting therefrom. The projecting portion is operated upon by means or tools to bend it away from the remainder of the spring as to form a loop and then impart a permanent set to a portion of the wire of the spring whereby to retain the loop in a desired orientation.

Description

United States Patent Clarke et al.

[451 May 16, 1972 [54] SPRING MAKING MACHINES AND METHODS [72] Inventors: Terence J. L. Clarke; Robert C. Quarmby; Kenneth Dennis, all of Union Works, Belgrave Road, Leicester, England 221 Filed: Apr. 30, 1970 211 Appl.No.: 33,271

[52] US. Cl ..140/103 [51] lnt.Cl. ..B21f35/02 [58] Field of Search 140/103 [56] References Cited UNITED STATES PATENTS 3,069,024 12/1962 Penny ..140/103 3,167,099 1/1965 Backman ..140/103 Bergevin et al 140/103 Wells 140/103 Primary Examiner-Lowell A. Larson Attorney-Richard A. Wise, Richard B. Megley and Cornelius A. Cleary [57] ABSTRACT The invention relates to machines and methods for use in forming attaching loops in generally longitudinal orientation at or from end portions of coil springs. A spring is supported by support means of a machine with an end portion to be looped projecting therefrom. The projecting portion is operated upon by means or tools to bend it away from the remainder of the spring as to form a loop and then impart a permanent set to a portion of the wire of the spring whereby to retain the loop in a desired orientation. 1

6 Claims, 9 Drawing Figures Patented May 16, 1972 3 Sheets-Sheet 2 Pi flaked May 16, 1972 3 Sheets-Sheet 5 SPRING MAKING MACHINES AND METHODS BACKGROUND OF THE INVENTION proved difiicult to provide machines capable of forming'such loops on both convenient and efiective bases. As a result'in many cases highly skilled labor is still necessary to-form the loops of acceptable quality. In this regard it has beenparticularly difficult on machines developed to date to provide the loops on springs, and even coil springs of an identical class with uniform and predetermined longitudinal orientation.

It is one of the various objects of the present .invention to provide an improved method for forming loops .at orfrom end portions of coil springs.

It is another of the various objects of the invention to ,provide an improved machine for forming .loops at or from end portions of coil springs.

SUMMARY OF THEINVENTION The present invention in oneaspect thereofcontemplates a method comprising supporting a spring bysupportmeans with an end portion of the spring projecting from the support means. A first portion of a first bending means or tool is moved transversely of the support means to separate -or reorient one or more coils or parts of coilsof the projecting portion from the remainder of the spring to provide aloop. A second portion of the first tool is then moved-transversely of the support means toengage the loop and bend or-.orient.it further again in longitudinal orientation. While the second portion of the first tool maintains theloop in :the further-bent position a second, setting or hammer meansortoolis moved toward the said second portionrof the first tooland =engagesa portion of the wire defining orforming .the loop or.a;portion thereof, between the second .tool and thesecondwportionof the first tool to impart atpermanent setto the wire and the longitudinal orientationofthe loop.

Preferably, incarryingout a method .as-set out :in the last preceding paragraph, itis arranged that after the-secondportion of the first tool has engaged the loop the firstxportion of the first tool is retracted so that it is clearofthe ;path..of the second tool. As a variation of that the first portion of .thefirst tool may be pushed from its innermostpositiontowards its outermost position by the second tool as it advances.

The present invention, in anotherof its aspects, contemplates a machinecomprisingsupport means including a-spring holder for supporting a spring with an end .portion of .the spring projecting from the support means. A .gage and preferably an adjustable gage means may .beincluded fonpositioning .the spring in the holder. The machinealso'includes a first or bending means or tool movabletransverselyofthe support means comprising a first portion .anda second portion movable along the same or ;parallel paths relative to each other transversely of the support means. The first :portion of the first tool has a leading end portion .adapted :tobe inserted between coils of a spring in the operation of the machine tosinitially separate orbend them away from the remainder of the spring and thus provide the endportion of-.the spring with oras a loop. The second portion of the first too] includesa bending face arranged so that during the transverse :movement .of that second portion it intersects a bending face of the leading end portion so that the loop separated by the leadingendportion-is engaged thereby and further bent. The machinealso includes a second, setting or hammer means or tool cooperative with the first tool in .the operation of the machine to impart a permanentset to the wire,,and more specifically a selected portion of the wire of the-spring whereby the loop retains the desiredposition or orientation introduced'to the same.

In apreferred embodiment of the. machine the first portion of the bending means or tool is at least partially accommodated ina slideway provided in the second .portion of the -bendingtoolto'facilitate movement .of thesame transversally of the support means. Specifically, in one manner forproviding that, the-first portion of the first tool is of T-shape cross section and includes a'plate portion arranged so that as the firstportion is moved transversely of the support means the plate portion slides over anend portion of a spring holder of the support-meansfrom which the, end portion of the spring at or from which'the loop is to be formed projects. The plate portion isthen disposed between said .end .portion of the spring holderand the second portionof the first or bending tool. The

first portion of;the first or bending-tool further includes a key projecting from the plate portion intoa groove providing a 'slideway for the'same'in said second portion with a leading end portion being provided by tapering the plate portion and :thekey'to a point lying in'theplane of the surface of the plate portion which slides overthe .end portion of the spring holder. .It is believed'that the plate'portion assists in controlling the remainder ofthe spring and in retaining the spring in the support means as the leading end :portion separates and bends the loop and during subsequent bending by the second portion of the first tool.

- The above and other of the-various objects and several features of the invention including various novel details of construction and combination of parts, will now be described in detail with reference to the accompanying drawings and pointed out in the claims. It will be understood that the described method and machine embodying the invention are shown by way of illustration only'and'not as a limitation of the invention. Specifically, in that regard, while the illustrative machine described is shown adapted for manual operation, it

in various and numerous embodiments without departing from the scope of the invention.

DESCRIPTION OF THE DRAWINGS In the accompanying drawings FIG. I is a view in'front elevation with parts broken away of the illustrative machine;

FIG. 2is aplan view withparts broken awayand in section of=the illustrative machine;

FIG. Bisaview in'sectionon the linelII-IIIof FIG. 2 showinga gage and aspring holder of theillustrativemachine;

FIG. 4a .to d are diagrammatic views broken away and in section showing .steps in the operation of the illustrative machine;

FIG. 5 is a view in front elevation partlybroken away and in section of a spring having a .loop formed by the illustrative machine; and

FIG.6 is a view in section on the line VI-VI of FIG. 2 showing-a tool holder and tools of aright hand tool block of the illustrative machine.

DESCRIPTION OF TH'E'ILLUSTRATED MACHINE As shown in the drawings, the illustrative machine comprisesabase 10 supporting a top member 11 which includes a groove 12, the groove .having a cross section in theform of an inverted T, see FIG. 3. A first right hand tool block 14 and a second left hand tool block 16 are located on top 11. The

tool blocks

14 and 16 each include a carrier '15 and a tool holder in the form of an inverted T extending across an upper face of the carriers 15, see FIG. 1 and 2. A projection 23 also in the fonn of an inverted T from the associated tool holder 17 is slidingly received in the groove 21, see also FIG. 1. The tool holders 17 may be readily locked at any desired position along the grooves 21 by means of lock bolts 19. The tool holders 17 along with their associated tools may readily be exchanged for other holders having different sets of tools, should this be required to accommodate different springs, by releasing the lock bolts 19, sliding the tool holders 17 out of the grooves 21 and sliding new tool holders in.

A bracket 20 secured to the carrier 15 of the right hand block 14, as viewed in FIG. 1, projects beyond a right hand end face 22 of the base and includes a downwardly projecting arm 24 into which is threaded an adjustable stop screw 26, see FIG. 1. A left hand end portion 28 of thescrew 26 abuts the end face 22 of the base 10 when the block 14 is in an innennost position and adjustment of the screw 26 accordingly affects that position. A compression spring 30 is supported by the screw 26 between the end face 22 and the arm 24 and urges the carrier and incidentally the block 14 towards the right, away from the innermost position, towards an outer position.

A bracket 44 secured to the carrier 15 of the left hand tool block 16 projects beyond a left hand end face 46 of the base 10. The bracket 44 includes a downwardly projecting arm 48, see FIG. 1. Located parallel with the groove 12 and secured to the base 10 is a screw member 50 which projects beyond the end face 46 and through a hole 52 in the arm 48. A nut 54 is threadably located on to the screw member between the arm 48 and the end face 46. Movement of the block 16 beyond an innermost position is prevented by engagement of the arm 48 with the nut 54. A second nut 56 is threadably located on an outer left hand end portion of the screw member 50, beyond the arm 48. Engagement of the arm 48 with the nut 56 prevents movement of the block 16 beyond an outermost position set by location of the nut 56 on the screw member 50.

The block 14 is shown having a horizontal operating lever 32 mounted for pivotal movement about a pivot pin 34, projecting upwardly from the bracket 20. A handle 36 is mounted on a front end portion of the lever 32, located forwardly of the pivot pin 34. A rear end portion of the lever 32 is pivotally mounted to an end portion of a link 38, the other end portion of which is mounted for pivotal movement about a pivot pin 40 carried by a boss 42 attached to the base 10. Similarly the block 16 is shown having an operating lever 33 pivotally mounted on the bracket 44 by a pin 35. The lever 33 is provided with a handle 37 at its front end portion. A rear end portion of the lever 33 is pivotally secured to a link 39 on a pivot pin 41 carried by a boss 43 attached to the base 10 in a manner similar to the mounting of the lever 32.

A groove 58 extends across a front face of the tool holder 17 of block 14, see FIG. 6, and an anvil plate 60 which provides a second portion of the first or bending tool is secured at the rear of that groove by a set screw 57. An anvil face portion 62 of the plate 60 projects beyond a left hand end face 64 of the block, see FIGS. 2 and 4c. A groove 67 extends across a front face of the anvil plate 60, see FIG. 6. A lifting tool 66 is also housed in the groove58 for sliding movement parallel to the movement of the block 14 in the groove 12 of the top 11. The lifting tool 66 comprises a first portion of the first or bending tool and comprises a plate portion 68 sliding in the groove 58; lips 61 prevent the first tool falling from the groove 58. A key 71 projects rearwardly from and extends across the plate portion 68 and is slidingly received in the groove 67 in the anvil plate which provides, as indicated above, a second portion of the first tool means. The lifting tool 66 also comprises a lifting finger 70 projecting beyond a left hand end of the plate portion and tapering to a point which lies in the plane of the front face of the plate portion 68, see FIG. 2.

A hammer 82 comprising a second or setting tool is mounted on the tool holder 17 of the left hand tool block 16, see FIGS. 1 and 4d. The hammer 82 constitutes a cylindrical rod 84 located in parallel relationship with the groove 12. A left hand end portion of rod 84 is received in a bore in the block 16 and locked therein by a set screw 88, see FIGS. 1 and 2. A right hand end portion of the rod 84 extends beyond a right hand end face of the block 16 and terminates in a notch 90, see FIG. 2.

A boss 92 is secured to a front edge portion of the base 10 at a central region thereof and projects above the top plate 11. A cylindrical passage, not legended, extends through the boss 92 so that the passage lies on a line extending generally from front to rear of the illustrative machine. A horizontal slit 102 extends inwardly from the left of the boss 92 and the plane in which the slit lies passes through the central axis of the passage. A screw 104 is threaded into a left hand upper portion of the boss 92 and extends across the slit 102 thus connecting the parts of the boss 92 at either side of the slit 102, see FIG. 1.

The boss 92 houses a tubular spring holder 106 having a spring-receiving bore 107. Attachment there is by means of screw 104. A front end portion of the spring holder 106 has a flange adapted to engage the boss in such a manner as to locate the spring holder 106 with its rear end portion projection rearwardly beyond the boss 92. A U-shaped notch 108 in the wall of the rear end portion of the holder 106 is aligned with the hammer 82 when the spring holder 106 is clamped to the boss by means of a peg 103 projecting forwardly from the boss 92, and carried in a notch 101 in the flange 100, see FIG. 1.

Mounted on a block 111 attached to the rear of the base 10 opposite the spring holder 106 in alignment therewith is an adjustable gage means comprising a tubular member 112 clamped to the block 111 between two arms 113 by means of a screw 115, see FIG. 2. The member 112 has a cylindrical bore in which a shank 114 of a locating member 116 is slidingly received, see FIG. 3.

The locating member 116 includes a head 118 secured by a screw 119 at a front end of the shank 114, see FIG. 2. A threaded rear end portion of the shank 114 projects beyond the tubular member 112 and a nut 120 is threaded on to that end portion. A compression spring 122 surrounds the shank 114 between the nut 120 and a rear end face of the tubular member 112 and urges the locating member rearwardly, see FIGS. 2 and 3.

Mounted beneath the tubular member 112 is a latch lever 124 which is capable of pivotal movement about a pivot pin 126 carried by a bracket secured to the member 112, see FIG. 3. A peg 128 secured to the shank 114 projects downwardly into a slot 130 in the tubular member 112 and thereby prevents rotation of the shank 114 with relation to the tubular member 112. A leaf spring 132 secured to the member 112 acts on a rear portion of the latch lever 124 to the rear of the pivot pin 126 to urge a latch portion of the lever 124 into the slot 130. The latch portion of the lever 124 comprises a shoulder 134 arranged to engage behind the peg 128 when the locating member 116 is in a locating, forward position with the spring 122 compressed whereby to hold the locating member 116 in the forward position, and, a nose portion 136 projecting beyond the shoulder 134 and resting against a lower portion of the peg 128 when the latch lever 124 is holding the locating member 116 in the forward position. A cam bar 138 is secured by bolts, not legended, to the rear of the left hand tool block 16 and projects to the right beneath the rear portion of the latch lever 124, see FIGS. 2 and 3. The cam bar 138 has a cam face 140 arranged to contact the rear portion of the lever 124 as the block 16 is moved to the left as it nears its outermost position whereby to pivot the lever 124 about the pin 126 and withdraw the shoulder 134 from the path of the peg 128 thus allowing the spring 122 to urge the locating member 116 rearwardly from its forward position to an extent determined by engagement of the head 118 with a front end of the tubular member 112.

The head 118 of the locating member 116 includes a front face 142 of generally spiral form from which projects forwardly a radial stop 144.

An upwardly projecting armof an L-shaped connecting bar 146 is secured to the front face of the lifting tool 66 and the other arm of the bar 146 extends leftwardly beneath the rear portion of the spring holder 106 behind the boss 92. A left hand end portion of that arm of bar 146 is connected to be slidable to an extent with the carrier of the lefthand tool block 16. A screw 152 located slidably in a slot 154 in the bar 146 and threaded into carrier 15 of tool block 16 provides for that. Screw 152 is then slidable in the slot 154 to the extent it engages a left hand end 156 or right hand end 158 of the slot 154. A tension spring 72 extends between a peg 74 projecting from a front face of the tool holder 17 of the tool block 14 and a peg 76 projecting from a plane front face of the connecting bar 146. The spring 72 urges the lifting tool 66 to the right to the extent determined by the effective length of the groove 58.

DESCRIPTION OF METHOD OF OPERATING THE ILLUSTRATED MACHINE When the illustrative machine is in a rest condition the right hand tool block 14 will normally be in the outer position to which it is urged by the spring 30 and the left hand tool block will be in a position intermediate the innermost and outermost positions set by the nut 54 and nut 56. A cycle of operation of the illustrative machine will now be described starting from the above rest condition.

The locating member 116 of the gage 110 is first moved to its forward position in which it is retained by engagement of the shoulder 134 of the latch lever 124 with the peg 128. A cylindrical coil spring 160 an end portion of which is to be looped is then inserted into the spring-receiving bore 107 of the spring holder 106 until the rear end of the spring engages the head 118 of gage means 110, see FIG. 4a. The spring 160 is then rotated in the bore 107 until the cut end of the wire of the spring engages the stop 144. The spring is thus located for the looping operation. In the setting up of the illustrative machine for fonning a particular type of loop in carrying out the illustrative method the locating member 116 of the gage and thespring holder 106 are arranged to allow a number .of coils of the spring to project beyond a rear end face of the spring holder 106 according to the number of coils to be used in forming the loop. The longitudinal position of the member 116 may accordingly be adjusted by slackening the screw 115, sliding the member 112 between the arms 113 until the head 118 is in a suitable position and tightening the screw 115 to reclamp the member 112, see FIGS. 2 and 3. The angular position of the radial stop 144 may be adjusted by releasing the screw 119, rotating thehead 118 on the shaft 114 and tightening the screw 119 according to the type of loop required, see again FIGS. 2 and 3.

The handle 37 of the operating lever 33 is then moved to the left thus drawing the block 16 to the left along the groove 12 towards its outermost position. The peg 152 slides the slot 154 of the connecting bar 146 until it engages the left hand end face 156 of the slot 154; further movement of the block 16 towards its outermost position moves the connecting bar 146 to the left and pulls the lifting tool 66 of the first tool to the left along the groove 58 against the action of the spring 72. The block 14 is kept stationary in the groove 12 by the action of the spring 30 which is stronger than the spring 72. As the block 16 nears its outermost position the cam face 140 of the cam bar 138 engages the latch lever 124 and pivots it to release the shoulder 134 from engagement with the peg 128 and allow the locating member 1 16 to be moved rearwardly by the spring 122 clear of the looping tools of the illustrative machine. The front face of the lifting tool 66 of the first tool then slides across the rear face of the springholder 106 and the point of the lifting finger 70 which is suitably shaped according to the spring 160 to be operated upon, engages between two of the coils of the spring 160 bending the rear one of the two (and anycoils to the rear of said rear one) away from the other to form a loop 162, the loop 162 sliding up the bending face 70 (see FIG. 4b). The outermost position of the block 16 is adjusted so that when it is reached, and, the tool 66 has reached an innermost position, the loop is bent sufficiently away-from the main body of the spring 160 for this particular part of the operation.

Next, with the block 16 held in its outermost position by means of the handle 37, the handle 36 of the operating lever 32 is moved leftwardly thus moving the right hand block 14 leftwardly away from its outer position towards its innermost position against the action .of the spring 30. As the block 14 nears its innermost position the anvil portion 62 of the anvil plate 60 of the first tool contacts the loop and bends it further to the left away from the remainder of the coil, see FIG. 40. The extent to which the anvil portion 62 bends the loop to the left depends on the innermost position of the plate 60, and, thusthe block 14. This is adjusted by positioning stop screw 26, see FIG. 1, according to the attitude of the final loop required and the size and strength of the wire of the spring 160.

The block 14 having reached its innermost position is maintained there, the handle 37 ismoved to the right thus moving the block 16 away from its outermost position to the right towards its innermost position. As the block 16 moves to the right the screw 152 in the slot 154, see FIG. 1, moves with the block 16 and allows thespring 72 to draw thelifting tool 66 and the connecting bar 146 to the right. As the lifting tool 66 is moved to the right the loop is maintained at the end of the spring 160 by the anvil portion 62 of the plate 60, see FIG. 4c. As the block 16 nears its innermost position the hammer 82 of the second tool passes through the notch 108 in the rear portion of the spring holder 106 and engages the wire of the spring at the region where the designated loop 162 joints the then remainder of the spring 160. The hammer 82 is so positioned that the wire in the region initiating or differentiating loop 162 is engaged in the notch at the end of the hammer 82 .to militate against the hammer 82 slipping past the wire of the spring 160. As the hammer 82 reaches its innermost position it moves in front of the front face of the anvil plate 60 and the wire is trapped between the hammer 82 and the anvil plate 60 and thereby pressed to give the wire at the indicated region of the same a permanent set, see FIG. 4d. The innermost position reached by the block 16 may be adjusted using the nut 54 on screw member 50, see FIG. 1, so that the hammer moves in front of the anvil plate sufficiently to impart a permanent set to the wire and thereby fix the loop 162 in a desired longitudinal orientation with respect to the remainder of the spring 160. The handle 36 may then be released and the block 14 is moved to its outer position by the spring 30. The handle 37 is then operated to move the block 16 to an intermediate position. The spring is then removed from thespring holder 106 of the illustrative machine and is found to have a loop connected at one end. The loop is longitudinally oriented with respect to the remainder of the spring. To state it again, it lies in a plane generally parallel to the axis of the coil of the spring 160. Loops may, however, be provided to have some other intermediate longitudinal orientation, if desired through adjustment of the illustrative machine, and specifically through adjustment of the tools of the same. If desired, by repeating the operation, a loop may be formed at the other end of the spring 160.

In a modified form of the machine, the anvil plate does not have a groove on its front face nor does the lifting tool have a key projecting rearwardly. In that form, the depth of the lifting finger from front to rear of the machine may be less than is possible using the groove arrangement. In order to form loops on a range of coil springs each made of wire of a different diameter a larger number of anvils, plates and lifting tools may be required using the modified form than would be required using the machine including the groove arrangement. However, the modified machine may advantageously be used in carrying out a method in accordance with the invention.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and, since certain changes may be made .in carrying out the above method and the constructions set forth without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in accompanying drawings shall be interpreted in an illustrative and not a limiting manner.

Having thus described our invention what we claim as new and desire to secure by Letters Patent of the United States is:

l. A method of forming a loop at an end portion of a coil spring which comprises the steps of supporting a spring by support means with a portion of the spring projecting from the support means, moving a first portion of a first tool transversely of the support means to bend at least a portion of a coil of the projecting portion away from the remainder of the spring to provide a loop, moving a second portion of the first tool transversely of the support means to an innermost position to engage the loop and bend it further, and maintaining the loop with the further bend with the second portion of the first tool in the innermost position while moving a second tool toward the second portion of the first tool to engage wire of the spring between the second tool and second portion of the first tool to impart a permanent set to the said wire.

2. A machine for forming a loop at an end portion of a coil spring comprising support means for supporting a spring with a portion of the spring projecting from the support means, and two tools, a first one of the tools being movable transversely of the support means and comprising a first portion and a second portion movable along parallel paths relative to each other, the first portion having a leading end portion adapted to be inserted between coils of a spring in the operation of the machine to initially bend them away from the remainder of the spring to provide a loop and the second portion having a bending face arranged to intersect during the transverse movement of the second portion a bending face of the leading end portion of the first portion so that the loop bent away by the leading end portion is engaged thereby and further bent away, and a second tool cooperative with the second portion of the first tool in an innermost position to impart a permanent set to wire of the spring to maintain the loop in a desired bent position.

3. A machine according to claim 2 wherein the first portion of the first tool additionally comprises a plate portion arranged so that as the first portion of the first tool is moved transversely of the support means in the operation of the machine the plate portion slides over an end portion of a spring holder of the support means from which the end portion of the spring projects, the plate portion being disposed between said end portion of the spring holder and the second portion of the first tool, and a key projecting from the plate portion into a groove providing a slideaway in said second portion, the leading end portion being provided by tapering the plate portion and key to the plane of the surface of the plate portion which slides over said end portion of the holder.

4. A machine according to claim 2 wherein adjustable means is provided for stopping transverse movement of said first portion of the first tool with the leading end portion thereof in a desired innermost position relative to a spring supported by the support means.

5. A machine according to claim 2 wherein adjustable means is provided for stopping transverse movement of said second portion of the first tool at a desired innermost position relative to a spring supported by the support means.

6. A machine according to claim 2 wherein adjustable means is provided for preventing transverse movement of the second tool beyond a selected innermost position relative to a spring supported by the support means.

Claims

1. A method of forming a loop at an end portion of a coil spring which comprises the steps of supporting a spring by support means with a portion of the spring projecting from the support means, moving a first portion of a first tool transversely of the support means to bend at least a portion of a coil of the projecting portion away from the remainder of the spring to provide a loop, moving a second portion of the first tool transversely of the support means to an innermost position to engage the loop and bend it further, and maintaining the loop with the further bend with the second portion of the first tool in the innermost position while moving a second tool toward the second portion of the first tool to engage wire of the spring between the second tool and second portion of the first tool to impart a permanent set to the said wire.