US2483865A - Sinusoidal spring forming machine - Google Patents

Description

Oct. 4, 1949. F. R. zlMMl-:RMAN l y2,483,865

SINUSOIDAL SPRING FORMING MACHINE Fild Nov. 15, 1945 '7 sheets-sheet 1 INVEN TOR.

am y-/M/ Oct. 4, 1949. F, R. Z|MMERMAN 2,483,865

SINUSOIDAL SPRING FORMING MACHINE Filed Nov. 15, 1945 '7 sheets-sheet 2 A I INVENToR. edZzmmermam Y BWM /Qzr /m/ Oct. 4, 1949. F, R zlMMERMAN 2,483,865

SINUSOIDAL SPRING FORMING MACHINE Filed Nov. 15, 1945 7 Sheets-Sheet 3 M QZZK Oct. '4, 1949. F R zlMMERMAN 2,483,865

SINUSOIDAL SPRING E ORMING MACHINE Filed Nov. l5, 1945 `'7' Sheets-Sheet 4 KQ m . INVENTOR. Zz/316@ JZZ mmermn Oct. 4, 1949. l F, R, zlMMERMAN 2,483,865

SINUSOIDAL SPRING FORMING MACHINE Filed NOV. 15, 1945 7 Sheets-Sheet 5 Oct. 4, 1949. F; R. ZIMMERMAN j 2,483,865

vSINUSOIDAL SPRING FORMING' MACHINE l Filed Nov. 15, 1945 7 sheets-sheets INVENTOR. ed ZL'mmer/m.

Oct. 4, 1949. F. R. ZIMMERMAN 2,483,865

SINUSOIDAL SPRING FORMING MACHINE Filed Nov. 15, 1945 7 sheets-sheet 7 INVEN TOR.

Patented Oct. 4, 1949 SINUSOIDAL SPRING FRMING MACHINE Fred R. Zimmerman, Davenport, Iowa, assignor to Nichols Wire and Steel Company, Davenport, Iowa, a corporation of Iowa Application November 15, 1945, Serial No. 628,799

14 Claims. (Cl. 1411-71) This invention relates to spring-forming machines for forming from spring-wire stock an elongated fiat spring consisting of a series of successive oppositely directed lateral folds. Such springs are generally set with a longitudinal curvature or arch and are referred to as nonsagging springs.

Heretofore there have been proposed various types of machines for forming springs of the type described. Certain of these machines have comprised a plurality of ,f Jrming posts, one or more wire-folding element and means for operating the folding element or elements to foldA the wire successively in opposite directions about the several forming posts in succession. the posts being withdrawn from the loop at some time subsequent to its formation.

These spring-forming machines of the prior art have been subject to several limitations, particularly with respect vto the size or gauge of the wire which they were capable of forming into springs. In the first place, if it is attempted to form a properly tempered, heavy gauge wire into springs of the type described, there is a tendency for the wire to slip from the formers or the folding elements, or both. On the other hand, if these elements are grooved in orderto engage the spring-wire stock firmly, the forming posts cannot be withdrawn from the plane of the folds after they are for-med. Furthermore, the mechanisms heretofore devised f or this purpose have been very complex, involving a large number of intricate moving parts unsuitable for withstanding the large forces involved in forming springs from heavy gauge stock.

It is an object of the invention, therefore, to provide a new and improved machine for forming from spring-wire stock an elongated fiat spring consisting of a series of successive oppositely lateral folds which is simple and rugged in construction and capable of forming springs from stock of any desired gauge.

It is another object of the invention to provide` a new and improved spring-forming machine of the type described in which the formers and the folding arms are all movable substantially in a common plane, thus avoiding the necessity of withdrawing the formers from the spring folds in a direction normal to the plane `of the spring after the folds have been formed.

In accordance with the invention, a machine for forming from spring-wire stock an elongated fiat spring consisting of a series of successive oppositely directed lateral folds comprises a pair of formers and a pair of folding arms individually cooperating with the formers. The machine further includes a first means for moving the formers alternately into forming position and a second means operating in timed relation to the first means for actuating the folding arms alternately to fold a stock wire about their respective formers. In a preferred form of the invention, the'stock-engaging portions of the formers and the folding arms move in generally horizontal paths, that is substantially in a common plane, thus avoiding the necessity of withdrawing the formers from the spring folds in a direction normal to the plane of the spring.

For a better understanding of the invention, together with other and further objects thereof, reference is had to the following description taken in connection with the accompanying drawings while its scope will be pointed out in the appended claims.

Referring now to the drawings, Figs. 1 and 2 are schematic top and side views, respectively, of a complete apparatus embodying the invention for forming springs of the type described; Fig. 3 is a side elevation and Fig. 4 is a top plan view of the spring forming machine, per se; Fig. 5 is a horizontal sectional view along the lines 5-5 of Fig. 13; Fig. 6 is an end view andFig. 'l a transverse vertical sectional view along the lines 1--1 of the spring forming machine of Fig. 3; Figs. 8-.11, inc., are perspective simplified views of the lower portion of the spring forming machine in several successive phases of operation;

while Figs. 12-17, inc., are fragmentary top views of the stock-engaging portions of the formers and the folding arms in several successive phases of operation. of the machine.

Referring now to Figs. 1 and 2 of the drawings, there is represented a complete apparatus for forming a spring of the type described. This apparatus comprises a reel 20 rotatably supported from a standard 2| for supporting a roll 22 of spring-Wire stock and feeding it to the machine of the invention. The stock from the roll 22 is passed through a series of vertical straightening Wheels 24 and a series of horizontal straightening wheels 25 before being fed to the machine 26 of the invention. The spring-wire stockis formed in the machine 26 into an elongated fiat spring consisting of a series of successive oppositely directed lateral folds, as described hereinafter, and the formed spring is wound 'on a take-up reel 21 for subsequent cutting into desired lengths.

The details of the spring forming machine 2G.

l 3 per se, will be best understood by reference to Figs. 3-7, inc., of the drawings. This machine comprises a pair of similar opposed generally vertically extending formers and 30a having grooved stock-engaging portions 3| and 3|a, respectively, at their adjacent opposed ends. The machine also includes means for individually supporting the formers 30 and 30a for combined pivotal and translatory movement. This means comprises a rigid frame 28 which may bevmade up of castings, rolled shapes, or the like, of sufcient strength to withstand the considerable forces involved in the spring-forming operation. Secured to the frame 28 are the pairs of bearings 32, 32 and 32a, 32a in which are mounted the pivot shafts 33 and 33a, respectively, which are disposed for both pivotal and axial movement. The formers 30 and 30a are provided with extended hubs 34 and 34a, respectively, which are supported from and secured to the pivot shafts 33 and 33a, respectively.

The machine of the invention also includes a pair of generally horizontally extending folding arms 40 and 40a individually cooperating with the formers 30 and 30a, respectively, and havinggrooved stock-engaging portions 4| and 4|a, respectively, which may be in the form of grooved rollers or pulleys to reduce frictional drag during the spring forming operation. There are also provided means for individually pivotally supporting the folding arms 40 and 40a which may be in the form of pivot shafts 42 and 42a, respectively, supported in the frame 28, the arms 40 and 40a, respectively, being provided with hubs 43 and 43a, respectively, mounted upon and secured to the pivot shafts 42 and 42a, respectively.

The machine of the invention also includes means for intermittentlyl moving the stock-engaging portions 3| and 3|a of the formers alternately into forming positions substantially in a given plane, specifically in generally horizontal paths. To this end there are provided two pairs of cams 35, 35 and 35a, 35a for individually moving the formers 30 and 30a in "one direction. as for example pivotally moving them about the axes of their pivot shafts 33 and 33a, respectively. The pair of cams 35, 35, which are similar, are mounted on a cam shaft 50 with a 180 displacement. These cams cooperate with and act upon cam followers in the form of rollers 36, 36 disposed at opposite ends of a transverse arm 31 of the former 30. Similarly, the pair of cams 35a, 35a engage rollers 36a, 36a disposed at the opposite ends of a transverse arm 31a of former 30a. It will be apparent that, rather than employing the pairs of cams 35, 35 and 35a, 35a, a single pair of cams 35 and 35a may be utilized for actuating the formers 30 and 36a, respectively, in one direction, the return movement being effected by suitable biasing springs.

There is also provided asecond pair of cams 38 and 38a, mounted on cam shafts 50 `and 50a, respectively, for individually moving the formers 30 and 30a, respectively, normalto the rst di rection, that is to impart a translatory motion to the formers, as by axially sliding the formers and their associated pivot shafts 33 and 33a axially in their respective bearings.' The cams 38 and 38a engage cam followers in the form of rollers 39, 39a mounted in extensions of the hubs 34 and 34a of the formers 30 and 30a, respectively, :o eiTect axial movement of the formers 30 and 30a and their associated pivot shafts 33 and 33a, respectively. The cam's 38 and 36a are, however, single-acting and the return movement of the forming operation. Considering first the phase` formers 30 and 30a is eected by means of biasing compression springs 48 and 49a, respectively, surrounding their pivot shafts 33 and 33a and engaging corresponding ends of their hubs 84 and 34a, respectively. The cam shafts 50 and 50a are supported in bearings 5|, 5| and 5|a, 5|a, respectively, secured to the frame 26. The cams 35, 35, 38 and 35a, 35a. 38a are designed with such a configuration that the formers 30 and 30a are alternately moved into and out of forming positions in open, substantially u-shaped paths and are then simultaneously advanced to close the Us and advance the formed spring, as explained in detail hereinafter.

The spring-forming machine of the invention also includes means operating in timed relation to the means for actuating the formers 30, 38a for actuating the folding arms 40, 40a in generally horizontal arcuate paths; that is, substantially in the same plane as the paths of movement of the stock-engaging portions 3|, 3|a of the formers 30, 30a, respectively, alternately to fold the stock wire about the respective formers. This means may be in the ,form of actuating cams 45, a individually engaging and actuating extended arms 44, 44a of the folding arms 40 and 40a, respectively. In order to effect more positive withdrawal of the folding arms 40 and 40a after a fold-forming operation, these arms are also provided with extending arms 46 and 46a, respectively, engaging withdrawal cams 41 and 41a, respectively. Obviously the cams 45 and 45a are complementary to the cams 41 and 41a, respectively, so that they continuously engage their respective followers during the working and return strokes. The follower arms 44, 44a and 46, 46a may carry ' anti-friction rollers 48 and 48a engaging their respective cams in order to reduce frictional drag and wear. The cams 45 and 41 are mounted on a cam shaft 52 supported from bearings 53, 53 secured to the frame 28 while the cams 45a and 41a are secured to a cam shaft 52a supported in bearing 53a, 53a secured to the frame 28.

'I'here is also provided a common driving means for all of the above described cams. This common driving means may be in the form of a power input shaft 54 which is connected to drive the cam shaft a through the spur gearing 55. The cam shaft 50a, in turn, is connected to drive the cam shafts 52 and 52a through one-to-oneration bevel gearing 56 and 51, respectively, while the cam shafts 52 and 52a are both connected `to drive the cam shaft 50 through the one-to-oneration bevel gearing 58 and 59, respectively. In this way the cam shafts 50, 50a, 52 and 52a are all interlocked to insure synchronous operation at all times, while the very considerable forces required in the spring-forming operation are uniformly distributed through the several driving cam shafts. As stated above, the operation of the formers 38 and 30a is intermittent and, in order to minimize binding and cramping of the cams and cam followers driving the formers 3|! and 30a. the several cams are so designed that the folding arms 40 and 40a are active to fold a stock wire about the formers 30 and 30a only when the latter are at rest. f

Referring now to Figs. 8-17, inc., of the draw ings, there are represented schematically simplifled views of the various steps in the movement of the formers 30 and 30a and the folding arms 40 and 40a during the several phases of the spring represented by Figs. 8 and 12, it is seen that the stock-engaging portion 3io of the former 30a anchors and restrains-the preceding loop or fold of the spring while the folding arm 4|! moves through the angie a to fold or bend the wire stock about the portion 3| of the former 3 to form the next oppositely directed fold. During this folding operation, the folding arm 40a, remains at rest. The next phase in the operation is represented by Figs. 9 and 13. During this interval, the stock-engaging portion 3Ia of former. 30a moves along the dotted r'line U-shaped path b of Fig. 13 into the position just occupied by the stock-engaging portion 4| of former 40. Simultaneously the folding arm 40 is withdrawn through the angle a to the position shown in Figs. 9 and 13. The succeeding phase in the springforming operation is represented in Fig. 14 in which the stock-engaging 'portions 3| and Sla of the formers 3i) and 3a, respectively, are permit-- ted to advance in the direction of the arrows under the influence of their biasing springs 49 and 49a, respectively, thereby advancing thel formers by the distance of one fold. During this step the portions 3l and 3|a are moved in a direction to close the U-shaped path b of Fig. 13.

The succeeding step in the operation is represented -by Figs. and 15 which illustrate the pivotal movement of the folding arm 4'0a through an angle a' equal to the angle a traversed by the folding arm 40, as described above. During this step in the operation, the portion 3| engages the previous fold of the spring and restrains the spring and holds it in position while the arm 40a folds the spring stock about the former portion 3io..

In Figs. l1 and 16 is represented the relative positions of the parts after the next succeeding step in operation in which the folding arm 40a is withdrawn through the angle a' to its initial position, while the former portion 3| is moved along the U-shaped path c and into position to serve as a fulcrum for the next folding operation by the arm 40. Finally in Fig. 17 the former portions 3| and 3|a are permitted to advance in the direction of the arrows under the influence of the biasing springs 49 and 49a, respectively, and thereby advance the formed portion of the spring by the distance of one foid.

The various steps described in detail above represent one complete cycle during which two adjacent oppositely directed spring folds are formed and this cycle is repeated indefinitely to form a spring of the desired length. It is seen that the formers 30 and 30a are alternately moved into and out of forming position in open substantially U-shaped paths and are then simultaneously advanced to close the Us and to advance the formed spring. It is also to be noted that the motion of the folding arms 40 and 40a occurs only during intervals when the formers 30 and 30a are at rest. This is a distinct advantage in avoiding the vbinding and cramping, due to the -considerable forces involved in the spring-forming operation, which would be encountered if it were attempted to actuate the folding arms while the formers 30 or 3Ua were in motion At the same time, it is seen that the spring-forming machine described is extremely simple, involving essentially only four spring-forming parts, the formers 30 and 30a and the folding arms 40 and 40a and their associated driving cams. At the same time, the construction is such that all of the parts may be made extremely rugged and capable of withstanding ,the forces involved in forming a spring of even the heaviest gauge stock.

lil

6 While there has been described what is at present considered to be the preferred embodiment of the invention, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit or scope of the invention.

What is claimedas new is:-

1. A machine for forming from spring-wire stock an elongated fiat spring consisting of a series of successive oppositely directed lateral folds comprising, a pair of formers having supporting means therefor positioning the formers vto extend away from one another in opposite directions, said formers each having a forming porf f tion adjacent one another and a driven portion separated from one another, a pair of folding arms individually cooperating with said formers, a first means for intermittently moving said fornicrs'at the driven portions alternately into forming position, and a second means operating in timed relation to said first means for actuating said folding arms only while said formers are at rest alternately to fold a stock wire about their respective formers.

2. A machine for forming from spring-wire stool: an elongated fiat spring consisting of `a series of successive -oppositely directedA lateral folds comprising, a pair of formers having supporting means therefor positioning the formers to extend away from one another in opposite directions, said formers each having a forming portion adjacent one another and a driven portion separated from one another, a pairrof'folding arms individually cooperating with said formers, a pair of cams for individually moving said formers lat the driven portions alternately into forming position, a second pair of cams for individually actuating said folding arms alternately to fold a stock wire about their respective formers, and a common driving means for all of said cams. y

3. A machine for forming from spring-wire stock an elongated fiat-spring consisting of a series of successive oppositely directed lateral folds comprising, a pair of formers having supporting means therefor positioning the formers to extend away from one another in opposite directions, said formers each having a forming portion adjacent one another and a moving portion separated from one another, a pair of fold-y ing arms individually cooperating with said formers, a rst pair of cams for individually moving Said formers in one direction, a second pair of cams for individually moving said formers normal to said first direction, whereby said formers are alternately moved into and out of forming position, and a third pair of cams for.

individually actuating said folding arms alternately to fold a stock wire about their respective formers, and a common driving means for all of said cams.

- 4. A machine for forming from spring-wire stock an elongated flat spring consisting of a series of successive oppositely directed lateral folds comprising, a pair of formers having supporting means therefor positioning the formers to ,extend away from one another in opposite directions, said formers each having a forming portion adjacent one another and a moving portion separated from one another, means for individually supporting said formers for combined pivotal and translatory movement, a pair of folding arms individually cooperating with said formers, means for individually pivotally supporting said folding arms, a first pair of cams for individually pivotally moving said formers, a second pair of cams for individually translating said formers, whereby said formers are alternately moved into and out of forming position. and a third pair of cams for individually actuating said folding arms alternately to fold a stoel: wire about their respective formers, and a common driving means for all of said cams.

5. A machine for forming from spring wire stock an elongated fiat spring consisting of a series of successive oppositely directed lateral folds and capable of being self-supporting as it moves through the machine in the forming operation, said machine comprising a pair of formers extending away from one another in opposite directions, means individually supporting said formers for combined pivotal and translatory movement, a pairof pivoted folding arms individually cooperating with said formers, a first means for moving said formers alternately into forming position in open substantially U-shaped paths and for simultaneously advancing said formers to close the Us and advance the formed spring, and a second means operating in timed relation to said first means for moving said folding arms.

6. A machine for forming from spring wire stock an elongated flat spring consisting of a series of successive oppositely directed lateral folds comprising, frame means having generally two portions disposed laterally relative to one another with a cam and shaft assembly in each portion, a pair of oppositely disposed pivoted formers each positioned in a frame means portion and each having a forming portion at the inner end and a driven portion at the outer end, with the driven portion of each being driven by a corresponding one of said two cam and shaft assemblies, a pair of pivoted folding arms individually cooperating with said formers, and means for driving said folding arms each in an arcuate path in timed relation to said formers and in a path substantially intermediate the two portions of the frame means.

1. A machine for forming from spring wire stock an elongated fiat spring consisting of a series of successive oppositely directed lateral folds and capable of being self-supporting as it moves through the machine in the forming operation, said machine comprising frame .means having generally two portions disposed laterally relative to one another with driving means in each of said two portions, a pair of formers having a driven part in each of said frame portions and a former part adjacent to one another in a position intermediate said two frame means portions, means for supporting said formers so that they are driven by said driving means into forming position in open substantially U-shaped paths, pivoted folding armsmovable individually in an arcuate path in timed relation to said formers, and means for moving said folding arms.

8. A machine for forming from spring wire stock an elongated fiat spring consisting of a series of successive oppositely directed lateral folds comprising, frame means, two pairs of cam and shaft assemblies mounted on the frame means and each pair thereof including a pair of cam shafts and cam means with the cam shafts of one of said two pairs of assemblies mounted parallel to one another and in a position extending in a direction at right angles to the position of the cam shafts in the other pair of said assemblies. a pair of oppositely disposed pivoted formers each having a forming portion at one end and a driven portion at the other end driven by one of said pairs of assemblies, a pair of pivoted folding arms individually cooperating with said formers and driven by the other of said pairs of assemblies, and means for driving the cam shafts in each of said assemblies.

9. A machine for forming from spring wire stock an elongated fiat spring consisting of a series of successive oppositely directedlateral folds comprising, frame means, a vfirst pair of cam and shaft assemblies each including a shaft and cam means with such shafts mounted in a parallel position on the frame means, a second pair oi cam and shaft assemblies each including a shaft and cam means with such shafts mounted in a parallel position on the frame means and at right angles to said shafts in said first pair of assemblies, a pair of oppositely disposed pivoted formers each having a forming tip portion at the inner end thereof and having a portion at the other end portion thereof in engagement with the cam means of one of the pair of assemblies, a pair of pivotr'l folding arms individually cooperating with said formers and each having a portion in engagement with cam means of said other pairof cam and shaft assemblies, and means for driving the cam shafts.

10. A machine for forming from spring wire stock an elongated at spring consisting of a series of successive oppositely directed lateral folds comprising, frame means, a first pair of cam and shaft assemblies each including a shaft and cam means with such shafts mounted in a parallel position on the frame means, a second pair of cam and shaft assemblies each including a shaft and cam means with such shafts mounted in a parallel position on the frame means and at right anygles to the position of said shafts in said first pair of assemblies, a pair of oppositely disposed individually operated formers each having a forming tip portion at the adjacent ends thereof and each having a portion at the seperated ends thereof in engagement with cam means of one of each of the respective pair of assemblies, means individually supporting said formers for combined pivotal and translatory movement, a pair of pivoted folding arms individually cooperating with said formers and each folding arm having a portion in engagement with cam means of said other pair of cam and shaft assemblies, and means for driving the cam shafts.

11. A machine for forming a spring product from spring wire stock which is suiliciently heavy to be self-supporting as it moves through the machine to be formed into successive oppositely directed lateral folds, such machine including in combination a pair of oppositely extending formers each having a forming head thereon, means supporting each former for forming movement and in -a position such that the two forming Iheads are overlapping, a pair of oppositely extending folding arms, means supporting said folding arms in a position such that they each pivot in a single plane which extends through each of said forming heads, with said forming heads and said folding arms entirely supporting and forming spring wire stock as it m-oves through the machine, and driving means operatively connected to said formers and said folding arms t0 drive them in timed sequence.

12. A machine for forming successive oppositely directed folds in spring wire stock which is sumciently heavy to maintain its folded configuration without support, such machine comprising a pair of formers having forming heads respectively adapted to be disposed in proximity to the wire stock on opposite sides thereof, mounting devices respectively supporting said formers for reciprocatory movements of said forming heads transversely of the wire stock in the directions of the respective folds, a pair of movable folding arms respectively adapted to be disposed on opposite sides of the wire stock near said formers, and driving means operatively connected to said formers and to said folding arms for driving them in timed sequence to fold the wire stock about said forming heads.

13. A machine for forming successive oppositely directed folds in spring wire stock which is sufficiently heavy to maintain its folded conguration without support, such machine comprising a pair of formers having forming heads respectively adapted to be disposed in proximity to the wire stock on opposite sides thereof. mounting devices respectively supporting said formers for reciprocatory movements of said forming heads transversely of the wire stock in the directions of the respective folds and also supporting said formers for reciprocatory movements of said forming heads longitudinally of the wire stock, a pair of movable folding arms respectively adapted to be disposed on opposite sides of the wire stock near said formers, and driving means operatively connected to said formers and to said folding arms for driving them in timed sequence to fold the wire stock about said forming heads and to advance the formed wire, said driving means including portions for respectively moving said forming heads transversely and longitudinally of the wire stock in conformity with closed paths that are substantially U-shaped in part to follow the congurations of the respective folds.

14. A machine for forming successive oppositely directed folds in spring wire stock which is sufciently heavy to maintain its folded configuration without support, such machine comprising a pair of formers having forming heads respectively adapted to be disposed in proximity to the wire stock on opposite sides thereof, each of said forming heads being grooved to receive and grip the wire stock, mounting devices respectively supporting said formers for reciprocatory movements of said forming heads transversely of the wire stock in the directions of the respective folds, a pair of movable folding arms respectively adapted to be disposed on opposite sides of the wire stock near said formers, and driving means operatively connected to said formers and said folding arms for driving them in timed sequence to fold the wire stock about said forming heads.

FRED R. ZIMMERMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date '761,640 Annable June 7, 1904 820,510 Mallett May 15, 1906 1,042,756 Beeman et al. Oct. 29, 1912

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