CA1263070A - Machine for production of coil springs - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
An apparatus for the production of coil springs con-sists of a transportation device having a series of radial grab arms for holding coil springs with frontal claws. The grab arms are driven in such a way that the coil springs are led, one after another and in sequence, to a series of work stations, arranged one after another in the sense of rotation of the grab arms. One work station is a spring coiling station, another following work station is a spring glowing station. The two terminal coils of the coil spring are provided with several spaced bending points, nearly arranged in U-shape by a bending station after the spring coiling station. The first bending station is followed by a sec-ond bending station of the same kind for the opposite terminal coil of the coil spring After having passed the spring glowing station, the finished coil springs are aligned in a spring align-ment station and led to a spring assembly machine.

Description

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The Inventlon relates to an apparatus for the produc-tlon of coll sprIngs.

Sprlny matresses for beds and seat furnlture generally 6 Include a number oF ~ouble-conlcal coll sprlngs, the ends of whlch are knotted In a known manner. The knots, for example, may be made by twlstlng the coll end wlth the ad.lacent sprlng coll.
In order to achleve an economlc productlon of such coll sprlngs, machlnes automatlcally wlnd the sprlngs from a wlre store, knot the two ends, and throw the flnIshed sprlngs Into a store channel whlch feeds an assembly machlne.

The Inventlon starts from such prlor art descrlbed In German Patent DE-PS 1 073 995 of the same applIcant.
U.S. Patent No. 2,581,6~6 dlscloses a sprlng core at whlch the free ends of the coll sprlngs are Interlaced wlth the termlnal colls of the adJacent coll sprlngs. Thls sprlng core Is not sultable for automatlc productlon slnce the Interlaclng of coil sprlngs Is a dlfflcult procedure.

In Brltlsh Patent 807,194, the coll sprlngs are con-nected to each other along rectlllnear, comparatlvely long side portlons. The productlon of such coll sprlngs Is relatlvely Intrlcate and needs a lot of wlre.

An obJect of the Inventlon Is to develop a ~achlne for the productlon of coll sprlngs accordlng to the German Patent DE-PS 1 073 995 In such a way that the coll sprlngs may be rapldly produced wlthout knottlng.

Accordlng to the present Inventlon there Is provlded anapparatus for the productlon of coll sprlngs formed from a length of wlre and havlng flrst and second free-endlng termlnal colls whlch are bent In a nearly U-shaped manner and whlch, In the dlrectlon of the sprlng axls, lle one upon the other, sald appa-,,~ \ ' ~

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ratus comprlslng a serles of rotatable, radlally extendlng grabarrns wlth claws for conveylng each coll sprlng to a serles of work statlons arranged one after ~e other reiatlve to the sense of rotatlon of the grab arms, one work statlon constltutlng a sprlng colllng statlon and another followlng work statlon constltutlng a sprlng glowlng statlon, a f Irst bendlng statlon arranged behlnd the sprlng colllng statlon In the sense of rotatlon of the grab arms for bendlng sald fIrst termlnal coll sharply In a nearly U-shaped manner at several spaced bendlng polnts, and a second bendlng statlon followlng the fIrst bendlng statlon for bendlng the second termlnal coll sharply In a nearly U-shaped manner at several spaced bendlng polnts, and sald sprlng glowlng statlon followlng the second bendlng statlon for rellev-!ng tenslon In the bent colls.
15, It Is an Important feature of the Inventlon that the knottlng devlces, descrlbed In German Patent DE-PS 1 073 g95, be replaced by bendlng statlons whlch bend the termlnal colls of the respectlve coll sprlng to ~n approxlmate U-shape and provlde the zO termlnal colls wlth a number of spaced bendlng polnts.

The precedlng round termlnal coll now wlll be bent to an approxlmately U-shaped termlnal coll. Thls has the advantage that the termlnal coll offers a larger bearlng surface to the upholstery and that the forces actlng under an angle wlth regard to the sprlng axls can be better absorbed.

The provlslon of bendlng polnts In the portlon of the termlnal colls of the coll sprlng has the further advantage that wlth the ald of these bendlng polnts, the coll sprlng can be very accurately posltloned In an assembly channel. As a result, the speed of a followlng sprlng assembly machlne can be substantlally Increased and the preclslon of assembly of the sprlng cores can be Improved.
~5 The replacement of dlfflcult producable knottlngs by :~2~3~7~

bendlng polnts has advantages as to the savlng of wlre stores as well as to Increase In the productlon speed o~ the coll sprIngs.
Moreover, the sprlngs can be very accurately allgned after pro-ductlon. Thls Increases t~le productlon speed of the -Fo I I ow I ng assembly machlne.

Two sprln~ bendlng statlons are opposltely dlsposed.
One statlon makes the bendlng polnts at one termlnal coll. The opposlte sprlng bendlng statlon provIdes the other terminal coll of the coll sprlng wlth the same bendlng polnts.
The apparatus wlll work wlth only one sole sprlng bendlng statlon. In thls case, after the productlon of one ter~
mlnal coll, the coll must be turned In order to make It posslble to bend the other termlnal coll by the same sprlng bendlng sta-tlon.

In a preferred embodIment pursuant, each bendlng sta-tlon conslsts of a control part, arranged at a toolplate, the termlnal of the coll sprlng belng placed upon the outslde clrcum-ference of the central part wlth a certaln radlal clearance.
Padlally dlsposed about the central part are provlded several bendlng tools, whlch are dlsplaceable In the dlrectlon towards the central part. Each bendlng tool Is movable towards the ~er-

2~ mlnal coll to be bent.

Preferably flve dlfferent bendlng polnts are provldedat the respectlve termlnal colls. Proceedlng from the ascendlng splral coll In dlrectlon towards the termlnal coll, a fIrst bend-Ing polnt can be provlded at the transltlon between the ascendlngsplral coll and the termlnal coll. After a fIrst slde portlon, a second bendlng polnt follows, followed by a thlrd bendlng polnt after a fIrst strap. The thlrd bendlng polnt Is followed by a fourth bendlng polnt after the passage of a second slde portlon and then followed by a fIfth bendlng polnt after a short passage of a second strap. The flfth bendlng polnt forms a bent end, ~;~63~7~

whlch Is bent out of the p~ane of the termlnal coll and takes an Incllned course relatlve to the sprlng axls.

The base of the termlnal coll, bent In U-shape, Is formed by the relatlvely long fIrst strap, to the two sldes of whlch Is Jolned a short fIrst slde portlon, ,and at the opposlte slde Is Jolned a larger- second slde portlon.

Thls second longer slde portlon Is followed by a second relatlvely short strap, followed by a bent end at an InclIned angle wlth the regard to the sprlng axls. The bent end Is bent Inwardly towards the sprlng axls and Is always dlrected towards the Interlor of the coll sprlng. Several advantages are simulta-neously obtalned. On the one hand, the bent end equalIzes wlrs ends wlth dlfferent lengths. When a longer wlre has been cut and manufactured, the extenslon wlll be placed In the bent end dlrected downwards at an Incllned angle relatlve to the sprlng axls. The bent end Is also Incllned Inwardly towards the sprlng axls In order to avold rubblng at the upholstery In the case of a composed sprlng coll.

Naturally, lt Is also posslble to make more or less than flve dlfferent bendlng polnts. ~owever, the proposed U-shape of the respectlve termlnal coll of the coll sprlng Is pre-ferred because the plane whlch Includes the termlnal coll Islarger than the plane whlch Is formed by the sprlng turns, whlch contlnue the termlnal coll. Thls results In that because of the larger plane of the termlnal coll, worklng forces In Inclined dlrectlon to the sprlng axls can be well transmltted to the smaller plane contalnlng the turns Iylng under the termlnal coll.
The provlslon of fIve dlfferent bendlng polnts In the portion of a U-shaped bent termlnal coll has the further advan~
tage that klnks are formed whlch can be used for the posltlonlng of the coll sprlng In an allgnment statlon.

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Dlagonally opposed bendlng polnts engage the allgnment cams of correspondent alIgnment levers of an alIgnment statlon so that the coll sprlng can be exactly allgned and conveyed to a f o I I ow Ing assembllng machlne.

An especlally preclse bendlng results when the termlnal coll of the coll sprlng is f I xed by the head of a holdlng-down appliance at the outslde clrcwnference of the central part durlng the whole bendlng process. Thls prevents the termlnal coli from falllng off the central part durlng the bendlng process.
Each bendlng tool can be fIxed to a slIde whlch Is dls-placeable In the radlal dlrectlon towards the central part. Each slIde rhythmlcally engages the termlnal coll one after another.
The termlnal coll Is fIxed by the holdlng down appllance at the central part.

It Is Important that only one central drlve be used for all slIdes and for the hold-down appllance. The cost of the machlnes, equlpment and malntenance are substantlally reduced.

Preferably, the resPectlve bendlng tool only dlsengages the termlnal coll sprlng when the respectlve followlng bendlng tool has already engaged ~he termlnal coll. As a result, one of 2~ the bendlng tools aIways makes posltlve contact wlth the termlnal coll of the coll sprlng. An Inadmlsslble movement and bendlng oF
the termlnal coll Is thereby prevented at the outslde c~rcumfer-ence of the central part.

Wlth only one central drlve, It Is posslble to drlve all slldes by only one curve dlsk. At each slIde Is arranged a revolvlng roller, the axls of revolutlon of whlch Is normal to the longltudlnal axls of the slIde and engages the closed curve path of a motor-drlven curve dlsk.
~5 The curve dlsk ls drlven by a sprlng-welghed engageable ~2~

and dlsengageable claw clutch In such a manner than the claw clutch connects the curve dlsk to the motor shaft for exactly one revolutlon, and dlsconnects after that. The fIve dl~ferent bend-lng polnts at the termlnal coll of the coll sprlng are made pre-clsely durlng one revolutlon of the curve dlsk, whereafter thecurved disk Is dlsconnected and stopped by the claw clutch of the motor shaft.

It Is an Important advantage of the present Inventlon that by provldlng approprlate bendlng polnts at the termlnal colls of the coll sprlng, a very exact posltlonlng of the coll sprlng Is posslble In a followlng sprlng allgnment statlon.

The sprlng allgnment statlon, at least In the portlon of a termlnal coll, can have two swlnglng alIgnment levers, on the swlnglng front ends of whlch are arranged an allgnment cam whlch respectlvely engages one bendlng polnt of the termlnal coll of the coll sprlng. Moreover, the allgnment cams engage dlago-nally opposed bendlng polnts of the termlnal coll; thls has the advantage that the termlnal coll, turned and fIxed by the allgn-ment cams, Is cla~ped In the conveyer ~elt exactly In thls posl-tlon and can be carrled to the assembly machlne by the conveyer belt.

The Inventlon wlll now be descrIbed In more detall by way of example only wlth re~erence to the accompanylng drawlngs, In whlch:-Flg. 1 Is a perspectIve vlew of a coll sprIng, the ter-mlnal colls of whlch are bent by a machlne accordlng to the Inventlon;

Flg. 2 Is a top vlew of the lower termlnal coll of the coll sprIng In FIg. 1, seen In the dlrectlon of arrow ll.

Flg. 3a Is a schematlcally drawn front vlew of a 7~

machlne accordlng to the Inventlon;

Flg. 3b Is a top vlew of the central part of a bendlng statlon wlth radlally arranged bendlng tools;

Flg. 4 Is a complete front vlew of a bendlng statlon accordlng to the Inventlon;

Flg. 5 Is a sectlonal vlew accordlng to the llne B-B In Flg- 4;
Flg. 6 Is a sectlonal vlew accordlng to the llne D-D In Flg. 4;

Flg. 7 Is a sec~lonal vlew accordlng to the llne A-A In Flg. 4;

Flg. 8 Is a sectlonal vlew accordlng to the llne C-C In Flg. 4;

Flg. 9 Is a vlew In the dlrectlon of arrow E In Flg. 5;

Flg. 10 Is a longltudlnal sectlon through the drlve of the curve dlsk for the radlal drlve of the bendlng tools;

Flg. 11 Is a sectlon through a control devlce for the control of the claw clutch;

Flg. 12 Is a slde vlew of the drlve devlce accordlng to Flg. 10;

Flg. 13 Is a further control devlce of the claw clutch;
.
Flg. 14 Is the locklng lever (shown In Flg. 11~ In another sectlonal vlew;

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Flg. 15 Is a schematlcally drawn slde vlew of the sprlng allgnment sta-tlon for the one terminal coll of the coll sprlng;

Flg. 16 Is a front vlew of the sprlng alIgnment statlon In Flg. 15;

Flg. 17 Is a top vlew of the sprlng allgnment statlon In the embodiment accordlng to Flg. 18; and Flg. 18 Is a slde vlew of the sprlng alIgnment statlon for the opposlte termlnal coll of the coll sprlng.

The coll sprlng 10 shown In FIg.s 1 and 2, whlch has a 16 double cone form, Is formed by a wlre plece havlng two opened termlnal colls 11 and two splral colls 15,16. The termlnal colls 11 at the front slde are U-shaped and lle one upon another as seen In the dlrectlon of the sprlng axls 17.

Comlng from the descendlng splral cGII 16, a fIrst bendlng polnt 5 Is provlded In the portlon of the termlnal coll 11 by means of apparatus accordlng to the present Inventlon, fol-lowed by a fIrst relatlvely short and curved slde portlon 13.
The slde portlon 13 Is flnlshed by a second bendlng polnt 6, fol-lowed by a relatlvely long curved sectlon 18, whlch Is termlnated by a thlrd bendlng polnt 7.

The thlrd bendlng polnt 7 Is followed by a second slde portlon 12, whlch Is opposlte and parallel to the fIrst portlon 13, but longer. The portlon 12 Is termlnated by a fourth bendlng polnt 8, followed by a short second sectlon 18a, the longltudlnal ~xls of whlch Is Incllned In relatlon to the longltudlnal axls of the fIrst strap 1~; the strap 18a Is fInlshed by a fIfth bendlng polnt ~, foilowed by the bent end 14, whlch Is bent out of the drawlng plane, Incllned, and dlrected upwards.

A

Flg. 2 shows that the plane whlch Includes the termlnal colls 11 Is larger than the plane whlch Includes the subJacent splral colls 15,16. Hence l-t follows that the termlnal colls 11 press agalnst the upholstery wlth a relatlvely large surface and, therefore, can well transmlt oblIque and lateral forces to the splral colls 15,1~.

The bent end 14, whlch Is always bent Inwardly In the dlrectlon of the sprlng axls 17, equallzes dlfferent sprlng lengths dur I ng the productlon of the coll sprlng 10.
In a subsequent sectlon It wlll be shcwn that, wlth the provlslon of the fIrst bendlng polnt 5 and the thlrd bendlng polnt 7, an exact alIgnment of the termlnal colls 11 Is a sprln0 allgnment statlon 200 Is posslble so that a sprlng wlth hlgh pre-clslon can be dellvered to a followlng sprlng assembly machlne.
Such a sprlng assembly machlne has been made dlsclosed, for example, In the 5erman Patent DE-PS 1 552 150 oF the same appll-cant.

The feedlng of the assembly machlne for sprlng cores wlth these sprlngs has been llkewlse made known by the German Offenlegungsschrlft DE-OS 3 101 014.

In Flg. 3a Is schematlcally Illustrated an apparatus for the productlon of such coll sprlngs 10 uslng the bendlng sta-tlons 178,17g accordlng to the present Inventlon.

At a motor-drlven rotatable dlsk 181 are arranged sev-30 eral grab arms 182 to 185, radlally and equally dlstrlbuted at - the clrcumference. The free end of each grab arm 182 to 185 Is provlded wlth a claw 187, whlch can be actlvated by a clamplng mechanlsm (not shown). The rotatable dlsk 181 wlth the grab arms 182 to 185 rotates In the sense of rotatlon 186; the coll sprlng 35 10, belng In productlon, Is grabbed by the claw 187 from a sprlng colllng statlon 177 and, In the sense of rotatlon 186, trans-~,~

ported to the flrst bendlng s~ation 178 where the termlnal coll 11 wlll be placecl on the central Part 66 shown In Flg. 3b. Wlth the ald o~ -the slldes, Illustrated In the Flgures 4 to ~, and the drlvlng devlce, Illustrated In Flgures 10 to 14, the fIve bendlng polnts 5 to 9 are then made at the flrst termlnal coll 11 of the coll sprlng 10. The grab arm 183 then moves In the sense of rotatlon 186 In the cadence of steps whereby the opposlte terml-nal coll 11 of the coll sprlng 10 comes to the reglon of the sec-ond bendlng statlon 179. There thls termlnal coll Is provlded wlth the fIve bendlng polnts ~ to 9. After the further rotatlon In steps of the rotatable dlsk 181 In the sense of rotatlon 186, the flnlshed coll sprlng 10 Is brought between the holdlng elec-trodes of a sprlng glowing statlon 180 where the tenslons caused by the cold deformatlon, are compensated at a temperature of 300C. The sprlng Is sllghtly twlsted so that an Immedlate con-veyance of the coll sprlng 10 to an assembly machlne would not be posslble. Therefore, the sprlng allgnment statlon 200, descrlbed In the Flgures 15 to 18, follows the sprlng glowlng statlon 180.
By means of the exlstlng bendlng po!nts In the portlon of the termlnal colls 11 of the coll sprlng lO and In the reglon of a conveyer belt 207, an exact alIgnment of the coll sprlng 10 Is posslble. The flnlshed sprlngs are successlvely put In the chan-nel for conveyance of a conveyer belt 207 and brought to an assembly machlne for sprlng cores accordlng to the technlcal teachlng of the German Offenlegungsschrlft DE-OS 3 101 014.

Flg. 3b schematlcally shows a portlon of the Illustra-tlon In ~Ig. 4, namely the coordlnatlon between the Indlvldual bending tools and the central part 6~. The termlnal coll 11, whlch Is to be provlded wlth the fIve bendlng polnts, Is lald on the outslde clrcumference wlth radlal clearance; by means of the grab arms 182 to 185 provlded wlth claws 187 accordlng to the Illustratlon In Flg. 3a.

The flrst bendlng polnt ~ Is made by a bendlng tool 78 that has two polnts whlch are separa~ed from each other by an A

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Intermedlate openlr)g 167. The above polnt In Flg. 3b Is formed as a slant 168 whlch lles Parallel to the coordlnated plane at the cen~ral part 66.

The openlng 167 Is nearly U-shaped and ends In a polnt 166 whlch obllquely engages the openlng 167. Thus, the flrst bendlng polnt 5 Is made by presslng and bendlng the termlnal coll 11 over the polnt 100 of the central part 66.

The second bendlng polnt 6 .s made by the bendlng tool 70, whlch Is dlsplaceable In dlrectlon of Its longltudlnal axls and radlally movable In relatlon to the central part 66. The bendlng tool also has a polnt 71 opposlte to an openlng In the central part. In the bendlng tool 70, the polnt 71 Is followed by an openlng 78 and a head 73, whlch Is opposlte an openlng In the central part 66. The polnt 71 and the head 73 of the radl-ally moved bendlng tool 70 engage In coordlnated openlngs of the central part 66 whllst the bendlng polnt 6 Is made by laylng the polnt 77 of the central part 66 agalnst the termlnal coll 11.

Before any bending tool beglns Its work, the hold-down appllance 23 engages wlth Its head 176 In the openlng 80 at the central part 66. As a resuIt the termlnal coll 11 of the coll sprlng 10 Is held fast under the head 176 of the hold-down appll-ance 23. Not before the termlnal coll 11 Is fIxed by thls manner at the central part, the bendlng tools push forward one after another agalnst the central part, the bendlng tools push forward one after another agalnst the central part, whereby the bendlng tool 78 makes the fIrst bendlng polnt 5, the bendlng tool 70 3Q makes the second bendlng polnt 6, and.the wedge-shaped bendlng tool 64 forms the thlrd bendlng polnt 7.

The fourth bendlng polnt 8 Is made by the bendlng tool 87 whlch Is radla~ly and inwardly dlsplaced towards the center of the central part 66, conJolntly wlth another bendlng tool 79.

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The bendlng tool 87 conslsts of two parallel edges 174 at the same level, Interrupted by an Intermedlate openlng 175.
The bendlng polnt 8 Is made by movlng the edges 174 Into respec-tlve openlngs at the central Part 66, whereby the bendlng of the termlnal coll Is executed over the polnt 173 of the central part 66.

The bendlng tool 79, slmultaneously pushlng forward wlth the bendlng tool 87, presses the resldual and the free end of the termlnal coll 11 on the surface of the bendlng tool 169, whlch Is formed llke an oblIque knlfe. The bendlng tool 169 In contrast to the bendlng tools prevlously descrlbed, extencls upwardly and normal to the drawlng plane In Flg. 3b and l~ mov-able so that the Inwardly bent end 14 o~ the termlnal coll 11 can be formed, The bendlng tool 169 lles upon a statlonary support 170.

The head 171 of the bendlng tool 1~9 enters Into the openlng 172 at the central part 66 In such a way that the wlre set down on the surface of the bendlng tool 169 can be surely grabbed from below.

Further detalls of the bendlng tools and the slIdes are Illustrated In Flgures 4 to 9.

The hold-down appllance 23 In the Flgures 4 and 5 Is movable In dlrectlon of Its longltudlnal axls.

: The axlal longltudlnal movement of the hold-down appll- ance 23 Is achleved by the lever 2, whlch passes through the tool plate 3 In the reglon of a gulde 21 and, on the back slde, by a bolt 24 wlth a control roller 26 engaglng the curve path of the rotatlng, motor-drlven curve dlsk 19.

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The upper part of Flg. 5 shows the sllde 1 that Is con-nected wlth the bendlng tool 169 (see Flg. 3b), maklng the bent end 14 at the termlnal coll 11. In Flg. 4, thls sllde I makes an oblIque movement normal to the drawlng plane, whlle the sllde In Flg. 5 moves In the dlrectlon of arrow 108. The swlvel polnt Is fIxed by a bolt 48, whereby the swlvelllng movement Is caused under the force of a pressure sprlng 61. The pressure sprlng Is arranged between a butt strap 31, fIxed by a screw 40, and a heavy tenslon pln 69 at the opposlte revolvlng part. The bolt 48 Is fIxed by a pln 54.
The swlvelllng movement of the bendlng tool 169 and of the sllde 1 In dlrectlon of arrow 108 Is performed by a cam 47 fIxed at the slIde 1 by means of a screw 41. The cam has a lower wedge plane to wh7ch Is coordlnated a wedge plane In the reglon of a oam 57 at the curve dlsk 19. When the two wedge planes meet, the cam 47 Is llfted and the slIde 1 tlIts around the axle 39 In the bolt 48.

The tlItlng movement Is llmlted by a stop 30 to whlch Is coordlnated a heavy tenslon pln 68 In the reglon of a gulde plate 32.

Each bendlng tool 64,70,78,87,169 Is connected wlth a 25 coordlnated sllde 1,35,45,55 whlch, respectlvely, grabs through the tool plate 3 and, accordlng to Flg. 7, has a bolt 36 at Its underslde wlth a rotatable roller 38.

The bolt 36 Is fIxed by a pln 54. The same Is provlded for the opposlte sllde In Flg. 7 wlth a bolt 37. Accordlng to the Flgures 7 and 4 the slldes are adJustable as to thelr longl-tudlnal dlsplacement In the dlrectlon towards the central part, whlle the lateral adJustment Is performed by lateral adJustlng of the screws 49 placed In correspondent lateral guldlng blocks.
Hereby, the tool plate conslsts of two pleces; on the relatlvely soft tool plate 3, there Is fIxed a harder Intermedlate plate 29 ~63~

by means of fIxlng screws 46; on the Intermedla~e plate 29, there Is arranged the gulde 27 for the dlfferent slldes, whereby the guide 27 has opposlte gulde grooves 60 whlch are provlded wlth addltlonal lubrlcatlng grooves 60 In whlch the slldes are gulded and dlsplaced In longltudlnal dlrectlon (see Flg. 8).

It Is stlll Important In Flg. 3 that the gulde 27 be tlghtly connected wlth the tool plate 3 by a screw 44, whlle the opposlte slde Is formed by a gulde block 63 whlch Is adJustable by means of two dlstant adJustlng screws 49 whlch pass through correspondent nuts 58. Thls makes an Indlrect adJustment of the sllde 35 posslble.
,) In FIg. 7, under the flanges of the bolts 37 can be seen the rollers 38, whlch engage correspondlng guldes of the curved dlsk 19.

The guldes 21 (Flg. 9) conslst of plastlc plates whlch are fastened to the tool plate by the ald of screws 42.

Moreover, the Flgures 4 and 5 show that, above the tool plate 3, a mountlng plate 4 serves for recelvlng the central part 66.

As to Flg. 4, the movement of the hold-down appllance 23 In dlrectlon of the longltudlnal axls of the hold-down appll-ance 23 and towards the central part 66 Is caused by the tenslon sprlng 62 whlch Is applled to the free outer end of the hold-down appllance 23 and connected by the other end wlth the houslng (not :30 detal led).
In the Flgures 10 to 14 are shown the detalls of the drlve of the curve dlsk 19; the drlve must have the followlng fundamental functlons:

The curve dlsk 19 must be drlven for Just one revolu-- 14 ~

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tlon; havlng completed the revolutlon, It must be stopped.

An overload coupllng mus~. exlst between the drlve and the curve dlsk 19 In or-der to separate the curve dlsk from the drlvlng motor If Inadmlsslbly hlgh movlng forces act upon the curve dlsk.

The drawlngs In Flgures 10 and 12 show only Indls-tlnctly that the curve dlsk 19 has Interlor curve paths 163 formed as open upward grooves as well as curve paths that run along the outslde clrcumFerence of the curve dlsk 19.

In Flg. 10 Is shown the flrm coupllr-g of the curve dlsk 19, havlng an eccentrlc outslde clrcumference, wlth an eccentrlc shaft 112 whereby the eccentrlc shaft Is connected wlth a stop eccentrlc 125 In the reglon of Its annular flange; the functlon of the stop eccenter wlll be detalled later on by means of the Flg. 14.

The eccentrlc shaft 112 Is rotatlvely supported In the drlve houslng 109 by two dlstant bushes 153,155.

The eccentric shaft 112 Is drIven by a claw clutch 154, wh Ich conslsts of two opposlte toothlngs 94,97 rotatlng Into one 25 another In the engaged state. The bush beionglng to the upper toothing 94 Is welghed by a pressure sPrlng 95 and presses agalnst the lower toothlng 97, provlded that the claw ciutch 154 has engaged.

The outslde clrcumference of the claw clutche 154 Is provided wlth an outer toothlng whlch engages a corresPondent toothed wheel 89 that Is flrmly connected wlth a shaft 122, which Is also rotatlvely supported In the drlve housing 109 by corre-spondent bushes 147,148.

The drIve of the shaft 122 Is performed by a further ~ ~D~

.
toothed wheel 1~99 whlch, however, Is not fIrmly connected wlth the shaft 122. Between thls toothed wheel 119 of the shaft 122 and a plnlon 12~7 f Irmly f Ixed at the motor shaft 84 Is arranged the overload clutch. Dlstrlbuted at the outslde clrcumference of the toothed wheel 119, there are arranged several fastenlng screws whlch engage a correspondent clutch rlng 110. Thls clutch rlng 110 Is flrmly conr1ected wlth the fastenlng screws. In rela-tlon to a hub 96, flrmly connected wlth thes shaft 122 by a wedge, the clutch rlng 110 Is rotatlvely supported by a needle bearlng 92.

Opposlte and coaxlally posltloned wlth regard to the clutch rlng 110, there Is provlded a second clutch rlng 102, whlch Is connected wlth the flrst clutch rlng 110 by sprlng-welghed rollers 91. The flrst clutch rlng Is supported In rela-tlon to the flange 121, whlch Is flrmly fIxecl at the houslng, by a dlstance dlsk 132 that captures the axlal forces.

The rollers 91 of the clutch rln~ 102 rotate In a U-shaped annular groove 93, whereby the rollers are pressed agatnstthe fIrst clutch rlng 110 by the force of a plate sprlng 8~. In dolng so, the plate sprlng 88 contacts wlth Its upper slde th~s underslde of the clutch rlng 102 and wlth Its opposlte slde a f lange 82, fIrmly f Ixed at the houslng.

The hub 96 Is fIxed at the front slde of the shaft 127 wlth the ald of a fastenlng screw 90.

If the torque at the shaft 122 becomes too great, for example because the curve dlsk 19 Is too much loaded, the rollers 91 run out of thelr annular grooves and the plate sprlng 88 Is compressed.

The clutch rlng 102 Is moved downwards In axlal dlrec-tlon, where, near the reference number 85, a contact swltch is provlded (not Illustrated) whlch stops the electrlc motor of the :

A

i~3~1t7Ci drIve.

The drive shaft of the electrlc motor drlves the motor shaft 84, whlch Is supported by two dlstant ball bearlngs sepa-rated agalnst one another by a rlng 140. The lower ball bearlngIs supported, by a dlstant rlng 137, agalnst a clutch rlng 99 of a further clutch, at whlch elastlc elements exlst whlch transmi~
the forces by full frlctlon. -rhe elements 98 engage correspond-lng paths o~ the annu~ar groove of a clutch 139 supported agalnst the drlve houslng 10~ In the axlal dlrectlon by a spacer rlng 138. Thls reglon Is covered by a.clutch bell 111, whereby at the bottom o$ the drlve houslng 109, a motor plate 114 Is arranged to whlch the electrlc motor Is flanged (not Illustrated).

~Ith reference to Flgures 12 and 13, the engaglng and dlsengaglng of the claw clutches 1~4 now wlll be explalned.

The engaglng of the claw clutch 154 Is performed ~y conductlng compressed alr to the cyllnder 115, whlch dlsplaces the clutch lever 118 In the dlrectlon to a stop In the houslng accordlng to the dash-dotted llne, whereby the center of motlon of the clUtch l~ver lles In a bolt 128.

The plvotlng movement of the clutch lever occurs agalnst the force of a sprlng 81.

The clutch lever 118 Is fIrmly connected wlth a control arm 116, whlch lles upon the outslde clrcumference of the tooth-lng 94 o~ the claw clutch 154. When the clutch lever 118 Is plv-oted accordlng to the drawn dash-dotted llne, the control arm 116 dlsengages the toothlng 94, and the claw clutch 154 engages by Its sleeve 1~6 under the force of the pressure sprlng 9~ so that the two toothlngs 94,97 can engage.

In order to stop the curve dlslc 19 after exactly one revolutlon, there Is provlded a stop devlce whlch wlll be : - 17 -descrIbed wlth reference to Flgures 11 and 14.

Beslde the prevlously descrlbed cylInder 115 for the engaglng of the claw clutch 154, there Is provlded a further cyllnder 117, whlch Is controlled by the same valve so that the two cylInders 115,117 are actuated at the same tlme. Accordlng ~o Flg. 11, the cyllnder ac~uates the stop lever 106 whlch Is turned around Its swlvel shaft 126. The swlvel shaft 126 con-slsts of a bolt th~t Is sup~orted by a base 101 whlch Is a con-stltuent part of the drlve houslng 109.

The swlvelIng movement of the stop lever 106 In clock-wlse dlrectlon caused by the cyllnder 117 occurs agalnst the force of a screw pressure sprlng 105, whlch acts upon a counter cam 104 of the stop lever 106. ~lereby, the free swlnglng front end of the stop lever 106 dlsengages the stop eccentrlc 1Z5 so that the curve dlsk 19 can exactly perform one revolutlon.

After the swlvelllng of the stop lever 106, the roller 135, arranged at the stop lever 106, runs along the outslde clr-cumference of the stop eccentrlc 125. Not before the complete revolutlon has flnlshed, that Is shortly before Its completlon, the stop lever engages control curve 127 by means of a screw pressure sprlng 105; the control curve 127 leads from the outslde clrcumference oF the dlsk-shaped stop eccentrlc 125 to the Inslde clrcumference.

The stop edge 161 at the opposlte end of the control curve 127 serves as a stop for the cor-respondlng control edge 162 of the stop lever 106. Havlng completed the revolutlon, the con-trol edge 162 o~ the stop lever 106 strlkes agalnst the corre-spondlng arrestlng plane of the stop edge 161. The whole curve dlsk 19 could unlntentlonally swlng back Into the opposlte dlrec-tlon. In order to prevent thls, there Is provlded a sprlng-welghed catch lever 144, whlch comes In an opposlte posltlon Inrelatlon to ~he stop edge 1~1. Thls avolds a swlng-back of the A

~3~

stop eccentrlc 125 and, by thls, of the curve dlsk 19. Wlth Its front slde, the catch lever 1~4 gears Into the dlsk 1~4 and strlkes agalnst the opposlte side of the stop edge 161 so that the stop edge wlll be I ocked by the stop lever 106 as we~l as by the catch lever 144.

1he stop occurs softly because the control edge 162 at the stop ~ever 106 Is a reslllent plate 134.

In Flg. 14 are shown the same condltlons once more, whereby the stop lever 106 Is represented as a sectlonal vlew, and It Is to be seen that the stop eccentrlc 125 conslsts of a dlsk 164 wlth an enlarglng dlameter, at the outslde clrcumference of whlch the control curve 127 Is arranged. The roller 135 of the stop lever 106 runs along the outer clrcumference of the dlsk 164 untll the roller reaches the reglon of the control curve 127.
Here~y, the stop lever 106 Is rotatlvely supported by a bolt 149.
The contact to the stop eccentrlc 125 occurs by the locklng block 131 whlch Is supported In the stop lever 106 by a reslllent plate 133.

The swlvel bearlng of the stop lever 108 Is Formed by the bolt 151 whlch Is flrmly fIxed In the base 101.

: 25 Referrlng to Flgures 12 and 13, the manual and the automatlc dlsengaglng of the claw clutche 154 now wlll be explalned more speclflcally.

Accordlng to Flg. 12, the claw clutch 154 has a counter cam 165 wlth a wedge-shaped Increaslng slant on whlch the corre-spondent slant of the cam 142, belng connected wlth the bush 146, runs up, so movlng upwards the bush 146 In the dlrection of arrow 103 and dlsengaglng the toothlngs 94,97. The counter cam 165 Is moved beyond the cam 142 by the curve dlsk 19, whlch Is stlll rotatlng; as a result the cam 142 falls downwards contrary to the dlrectlon of arrow 103, and the clutch Is ready for a new revolu-: -- 1 9 --`

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~63~

; tlon.
J
In order to avold a new engagement of the claw clutch 154 at thls moment, the control alr Is In the meantIme wlthdrawn 6 from the cyllnder 115. The piston rod returns to the rest posl-tlon, the clu-tch lever 118 ta~es the posltlon shown In Flg. 13 wlth full llnes and the control arm 116 engages the toothlng 94 and stops It.

; 10 Wlth the ald of the dlsengaglng lever 107, the claw ! clutch 154 may be d I sengaged, but not engaged. T~e dlsengaglng lever 107 Is rotatlvely supported by a bearlng 156 at the drlve houslng 109, and engages, wlth lts slantlng front end, In the reglon of the toothlng 94 of the bush 146, whlch Is dlsplaceable agalnst the force of the pressure sprlng 95.

Accordlng to Flg. 10, the pressure sprlng 95 Is sup-ported at Its upper end by a sprlng plate 145 whlch transfers Its axlal force to a bush 155. The bush 155 Is supported by a bear-20 Ing 124 In the drIve houslng 109.

The stop for the stop Içver 106 Is arranged at an angle 150 at the front slde of the drlve houslng. The stop lever strlkes wlth Its cover 130 agalnst the stop, provlded wlth rubber elements, when the cyllnder 117 Is actlvated.

The advan~age of the drlve devlce, descrlbed'by means of Flgures 10 to 14, Is that all slldes and ~ools of the bendlng devlce are actuated by the same central devlce. By thls, a rela-tlvely Inexpenslve and slmply produclble arrangement results,compared to four separate drlves whlch mUst be synchronlzed.
.
By means of Flgures 4 to 14, the whole functlon of the bendlng devlce for ~he productlon of the flve bendlng polnts at 36 the one termlnal coll 11 of the coll sprlng 10 has been explalned.

A

Accordlng to Flg. 3a, a second bendlng statlon 179 of the same klnd Is arranged behlnd the Flrst bendlng sta-tlon 17~.
In the second bendlng statlon 17g, the other termlnal coll 11 of the coll sprlng 10 Is provlded wlth the flve descrlbed bending polnts.

F I 9 . 3a shows that the coll sprlng, flnlshed by the second bendlng statlon 179, Is subsequently brought to a spring glowlng statlon 180. The two termlnal colls are contacted wlth the holdlng electrodes of the sprlng glowlng statlon 180. The coll sprlng 10 Is heated up to around 300C, whereby the tenslons due to the cold deFormatlon are equallzed. The coli sprlng wlll be sllghtly deformed, I.e. It wlll be twlsted and change Its length. Thls results In the fact that the flnlshed glowed coll sprlngs 10, lald down on the subsequent conveyer belt by the grab arm 185, are not exactly allgned.

The conveyer devlce is descrlbed In the German Offenle-gungsschrlft DE-OS 3 101 014. In the same descrlbed manner, the zO coll sprln~s are laId down onto a conveyer 207 that conslsts of two opposlte and synchronously drlven conveyer belts.

By means of Flgures 15 to 18, the sprlng allgnment sta-tlon 200, arranged In the reglon of the conveyer belt, wlll now be descrlbed. In thls sta~lon, the coll sprlng 10 Is exactly allgned, hereby utlllzlng the fIve bendlng polnts produced by the bendlng statlon accor~lng to the present Inventlon.

Flg. 15 shows one half of the conveyer belt 207 wlth Its belt runnlng In the dlrectlon of arrow 20~. The coll sprlng 10 Is only shown wlth one termlnal coll 11, whlch Is wound by the sprlng alIgnment statlon shown In Flgures 15 and 16. The oppo-slte termlnal coll 11 o~ the coll sprlng 10 Is wound by the sprlng allgnment statlon shown In Flgures 18 and 19.

The alIgnment of the coll sprlng Is performed by 3q~76~1 arranglng, at the machlne houslng, a statlonary sllde 210, whlch revolves around the axle 211, normally dlrected relatlve to the drawlng plane. The rotatlon Is achleved by a compressed alr cylInder 212, whlch works wlth Its plston rod 213 over a rubber element 214 upon the extended arm 215 of the control lever 216, whlch Is rotatlvely supported In the axle 211.

At the opposlte end of the control lever 216, the alIgnment lever 21~ Is fIxed wlth the ald of a fastenlng screw 217, the allgnment lever havlng the allgnment cam 219 at Its lower free end. Accordlng to Flg. 15, the allgnment cam engages the bendlng polnt 7 of the coll sprln~i 10; thus, the bendlng polnt serves as center of rotatlon and fIxlng polnt for the allgnment.

Opposlte to the allgnment lever 218 Is provlded a sec-ond alIgnment lever 221, whlch also has an alIgnment cam 222.
Thls allgnment lever 221 Is supported by the swlvelllng axle 224 at the machlne houslng and can be swlvelled In the dlrectlon of arrow 223 to the posltlon 221'.

When the alIgnment lever 221 Is swlvelled In the dlrec-tlon of arrow 223, the lower end of the coll sprlng comes to the drawn posltlon 10', whereby the alIgnment cam 222 engages the flrst bendlng polnt 5 of the termlnal coll 11 of the coll sprlng 10. Because the alIgnment cams 219,222 engage the bendlng polnts 5,7, whlch lle dlagonally opposed, a stable stralghtness of the coll sprlng Is obtalned, whlch Is exactly turned In such a way that the bendlng polnt 7 Is always at the top.

The swlvelllng of the lower alIgnment lever 221 Is per-formed by a compressed alr cyllnder 226, whlch, wlth Its plston rod Z27, over a hlnge plece 228 and a plvot bolt 229, Is plv-otally fIxed to the alIgnment iever 221. When the plston rod ~27 Is dlsplaced, the allgnment lever 221 can be brought In the drawn posltlon 221' In the dlrectlon of arrow 223.

¢~ ~

3~'7~ ~

There are provlded ieft- and rlght-slded stops 248~249/
whlch llmlt the respectlve f Inal posltlon of the ~ nment lever 221. In the Illustrated embodIment, a further compressed alr cylInder 230 Is provlde~, whlch by means of Its plston rod, presses the allgnment lever 221 outwards; thle allgnment lever Is deslgned as a leaf sprlng so that Its allgnm~ent cam 222 dlsenga-ges the term I nal coll 11 of the coll sprlng 10.

In a further, not Illustrated embodlment, the alIgnment lever 221 Is not deslgned as leaf sprlng but as a rlgld element whlch can be plvoted In a plvotlng bearlng, flxed at the machlne houslng, In the dlrectlon of arrow 232 and In the opposlte dlrec-tlon.

In Flgures 17 and 18 Is shown the opposlte sprlng allgnment statlon 200, where the allgnment of the opposlte terml-nal coll 11 of the coll sprlng 10 Is performed by the shown allgnment means.

Hereby a control sllde 233 Is agalh revolvable In nor-mal dlrectlon to the drawlng plane of Flgure 18. The control sllde 233 has a control cam 234, whlch engages the bendlng polnt 6 of the termlnal coll 11 of the coll sprlng 1Q. The swlvelllng of the coll sprlng 10 Into the posltlon 10', wlth the swlvel cen-ter In the portlon of the bendlng polnt 6 around the control cam 234, Is achleved by a control sllde 236 whlch Is dlsplaceable downwards In the dlrectlon of arrow 24Q In Flg. 18 and has a lower frontal control cam 237 that, In the portlon of the strap 18 of the termlnal coll 11 of the coll sprlng, strlkes agalnst the coll sprlng and turns the termlna! coll In the dlrectlon of arrow 235 Into the posltlon 10'.

The control slIde 236 is drlven by a compressed alr cyllnder 238 over a plston rod 239 and, accordlng to Flg. 18, Is dlsplaceable In the vertlcal dlrectlon.

~ ~ 3~t~

It Is Important that the control cam 237 contacts the termlnal coil 11 of the coll sprlng only at the outslde and that the coll has a cert~ln twlstlng clearance about the control cam ~34.

The allgnment statlon accordlng to Figures 1~ and 16 and the opposlte allgnment statlon accordlng to Figures 17 and 18 ~re synchronously drlven so that the allgnment oF the termlnal coll 11 of the coll spr~ng 10 Is made at the same tlme.

After the alIgnment has been made, the mentloned con-trol cams 219,222,234,237 dlsengage the correspondlng termlnal colls 11 of the coll sprlng by the coordlnated controi bars. The sprlng, allgned In thls way, Is transported In the dlrectlon of 15 arrow 208 by the conveyer belt 207 towards a transfer unlt, from where It Is carrled to the assembly machlne for sprlng cores. It should be mentloned that the control sllde 233 Is drlven by a compressed alr cyllnder 241, wh Ich Is shown In FIg. 18 In slde vlew and In Flg. 17 In plan vlew.

It Is also a feature of the present Inventlon that the provlslon of the bendlng polnts In the portlon of the two terml-nal colls of the coll sprlng occurs by a relatlvely slmple bend-lng machlne durlng the process of productlon of the coll sprlng, 2~ whereby the bendlng polnts, made by the bendlng machlne, are slmultaneously utlllzed for the exact allgnment of the coll sprlng for the purpose of feedlng a subsequent assembllng machlne.

3~

_ 24 -A

Claims (11)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. An apparatus for the production of coil springs formed from a length of wire and having first and second free-ending terminal coils which are bent in a nearly U-shaped manner and which, in the direction of the spring axis, lie one upon the other, said apparatus comprising a series of rotatable, radially extending grab arms with claws for conveying each coil spring to a series of work stations arranged one after the other relative to the sense of rotation of the grab arms, one work station con-stituting a spring coiling station and another following work station constituting a spring glowing station, a first bending station arranged behind the spring coiling station in the sense of rotation of the grab arms for bending said first terminal coil sharply in a nearly U-shaped manner at several spaced bending points, and a second bending station following the first bending station for bending the second terminal coil sharply in a nearly U-shaped manner at several spaced bending points, and said spring flowing station following the second bending station for reliev-ing tension in the bent coils.

2. An apparatus according to claim 1, wherein each bending station consists of a central part fixed to a tool plate, the terminal coil which is to be bent being carried at the out-side circumference of the central part and several radially arranged bending tools displaceable in the direction towards the central part, said bending tools being placed opposite the cen-tral part and being displaceable towards said terminal coil which is to be bent.

3. An apparatus according to claim 2, wherein, pro-ceeding from the ascending spiral coil in the direction towards the upper terminal coil of the coil spring, a first bending point is arranged at the transition between the ascending spiral coil and the upper terminal coil, followed by a second bending point after the passage of a first side portion, followed by a third bending point after the passage of a first intermediate section, followed by a fourth bending point after the passage of a second side portion, followed by a fifth bending point after a short passage of a second intermediate section, the fifth bending point forming a bent end which is bent out of the plane of the upper terminal coil and takes an inclined course relative to the spring axis.

4. An apparatus according to claim 1, wherein the ter-minal coils of the coil spring are fixed during the whole bending process by the head of a hold-down device at the outside circum-ference of the central part.

5. An apparatus according to claim 4, wherein each bending tool and the hold-down device are fixed on slides, each displaceable in the radial direction towards the central part and engaging the terminal coil in sequence one after another, the terminal coil being fixed by the hold-down appliance at the cen-tral part.

6. An apparatus according to claim 5, wherein the respective bending tool only disengages the terminal coil of the coil spring when the following bending tool has already engaged the terminal coil.

7. An apparatus according to claim 5, wherein at each slide is provided a revolving roller, the axis of revolution of which is normal to the longitudinal axis of the slide and which engages a closed curve path of a motor-driven curved disk.

8. An apparatus according to claim 7, wherein the curve disk is driven by a spring-weighed engageable and disen-gageable claw clutch such that the claw clutch connects the curve disk with the motor shaft exactly for one revolution and discon-nects it after that.

9. An apparatus according to claim 1, wherein the coil spring, after having passed the spring glowing station, is squeezed in a conveyer belt by the conjugated grab arms, the con-veyer belt bringing the coil spring to a spring alignment station in which the coil spring is exactly aligned before the insertion into an assembly machine.

10. An apparatus according to claim 9, wherein the spring alignment station, at least in the portion of a terminal coil, has two swinging alignment levers on the swinging front ends of which is respectively arranged an alignment cam which respectively engages one bending point of the terminal coil of the coil spring.

11. An apparatus according to claim 10, wherein the alignment cams engage diagonally opposed bending points of the terminal coil.