US2553796A

US2553796A - Spring coiling machine

Info

Publication number: US2553796A
Application number: US107973A
Authority: US
Inventors: Stussi Jacques
Original assignee: MARCHANT CALCULATING MACHINE
Current assignee: MARCHANT CALCULATING MACHINE; MARCHANT CALCULATING MACHINE Co
Priority date: 1949-08-01
Filing date: 1949-08-01
Publication date: 1951-05-22
Anticipated expiration: 1968-05-22

Description

May 22, 1951 J. sTussl SPRING coILING MACHINE 2 Sheets-Sheet l Filed Aug. l, 1949 L Flr-:11-25 INVENTOR.- Jacques Suss/ May 22, 1951 J. sTUssl 2,553,796

` SPRING coILING MACHINE Filed Aug. l, '1949 2 Sheets-Sheet 2 3l E-LLEJ;

I N VEN TOR.-

@E Jacques Suss/ Patented May 22, 1951 f UNITED STATES SPRING COILDIG MACHINE Jacques Stussi, Berkeley, Calif., assignor to Marchant Calculating Machine Company, a corporation of California Application August 1, 1949, Serial No. 107,973

6 Claims. (Cl. 153-67) The present invention relates to spring coiling machines and more particularly to machines for making small torsion springs. The invention also provides means for collecting finished springs on a length of wire or the like.

Machines for making torsion springs are well known in the art. In such machines, the free end of a length of wire stock is usually inserted between a mandrel and a coiling pin which is 'rotated to wind or coil the free end of the wire around the mandrel and produce a spring having one or more convolutions.

One requirement of a spring machine of this type is that during the coiling of the wire around the mandrel, the coiling pin and what is generally termed a coiling head upon which the pin is usually mounted, must be moved along the axis of the mandrel to permit each successive convolution of the spring to lie adjacent the previous convolution. Another requirement is that a positive contact must be maintained between the coiling pin and the wire throughout the coiling operation. g

' With respect to the axial movement of the coiling head and pin relative to the mandrel, such movement is not at a constant rate throughout the spring coiling operation since no axial movement is necessary or desirable during the winding of the rst convolution until the free end of the wire crosses over the held end of the wire. Thereafter each successive convolution follows the previous convolution and the axial movement of the coiling head and driving pin is at a Xed rate which, for each convolution, is equal to the diameter of the wire. If 'the axial movement is controlled by cams or other positive positioning means,then the cam must be designed to provide the different rates of axial movement described above for the rst and successive convolutions of the spring, and furthermore a dierent cam must be provided for different diameters of wire stock used in making the springs.

With respect 'to the requirement for holding the driving pin in contact with the wire at all times during the spring coiling operation, it will be noted that after the first convolution of the spring is formed, the wire is constrained between that convolution and the coiling head thus holding the wire in contact with the coiling pin. During the coiling of the first convolution, however, there is no previous convolution to guide the free end of the wire, and if the coilingl head and pin are moved axially relative to the mandrel to permit the crossover of the wire ends, there -is danger of the coiling pin losing contact with the wire. If, on the other hand, the coiling pin` is made long enough to prevent such loss of con-l tact, then the pin conflicts with the held end ci the Wire during the crossover.

The present invention provides an improved organization of mechanism for controlling the free end of the spring stock, particularly during the critical period when the rst convolution is being coiled and at the time of the flrst crossover. Thereafter, the mechanism automatically responds to the formation of the previous convolution to move the coiling pin and head axially at a rate which is determined by the ,progress of the coiling operation regardless of what diameter of wire stock is used.

'I'his is accomplished in the present invention by providing a deflecting member which has an angular surface for guiding the free end of the spring wire as it swings around the axis of the mandrel during the coiling of the first con-l volution. 'I'he aforementioned coiling head which, in the present invention may be more aptly termed the coil control head, also has an angular surface. The control head is spring urged toward the deflecting member and presses the spring stock between the two mating angular surfaces of the head and member to thereby deflect the free end of the wire out of the plane of the first convolution. Since the held endv of the length of wire stock is in the plane of the rst convolution, the free end passes over the held end without interference thereby during the rst crossover. During the coiling of subsequent convolutions, the spring urged control head yields axially relative to the mandrel as each convolution is coiled upon the other, and the previous convolution serves as the guide lfor, the free end to prevent interference thereof during subsequent crossovers. The spring pressure of the control head against the wire also serves to' maintain the coiling pin in contact withv the wire at all times. y

The primary requirements of machines of this class are therefore met by the simple expedients described above without requiring any cams or other positive positioning means for causing the axial movement of the coiling pin and head during the coiling operation.

The present invention is therefore based upon the principle of coiling the wire stock between two members, and yieldably urging these two members toward each other to deflect the free end of the wire stock out of the plane of the rst` convolution and the held end of the spring wire stock while the free end is coiled around a mandrel.

Another feature of the present invention is the provision of means for collecting finished torsion springs on a length of wire, or the like, thus preventing the springs from becoming entangled with one another. This is accomplished by providing a hollow or tubular mandrel around which the spring is coiled, and by inserting a collector Wire or rod through the center of the mandrel so that when the coiling of the spring is completed and the spring is ejected by any well known means such as a stripper or air jet, the completed spring will fall under the urge of gravity and be collected on the central wire or rod.

It is therefore a principal object of the invention to collect springs on a wire or rod which is inserted through a central hole of the coiling mandrel.

It is a further object of the invention to provide improved means for controlling the path of the free end of the length of wire stock to prevent interference between the free end and the held end of the wire during the coiling of a torsion spring.

It is a further and more specific object to guide the free end of a length of spring wire stock by the mating deflecting surfaces of two coil control members and to yieldably urge said Vcontrol mem bers toward each other during the coiling operation.

Other objects of the invention will become apparent from a detailed description of the invention in which:

Fig. l is a top view of a spring coiling machine showing the principal elements thereof. In this view the front of the machine is at the right side of the drawing.

Fig. 2 is an enlarged top view, partly in section, showing the cutting tool holding one end of the wire while the coiling pin and the free end of the wire are shown in progressively advanced positions of rotation around the mandrel.

Fig. 3 is an enlarged front view, partly in section, showing the means for yieldably holding the control head and coiling pin in ycontact with the free end of the wire.

Fig. 4 is a front view showing the coiling pin and the free end of the wire rotated 270 from its initial position and also showing the means for collecting the springs upon completion thereof.

Fig. 5 is a side view showing the control head holding the Wire against the member which deilects the free end of the wire in a selected path during the coiling of the rst convolution of the spring.

Fig. 6 is an enlarged perspective of the deilecting member or yoke shown in Fig. 5 with the wire shown in its initial position after the feeding operation.

The spring coiling operation is controlled by three cams I, 2 and 3 (Fig. l) which are fixed to a drive shaft 4, suitably mounted in the framework of the machine. The three cams operate through cam followers to control the respective movements of a yoke 5, a cut-olf blade 6, and a gear segment I which drives the coiling pin. The yoke and the cut-olf blade are mounted for endwise sliding movement in respective channels in a guide block 33 fixed to the frame of the machine. The segment 'I is freely pivoted on shaft I9 carried by the framework of the machine and is urged counterclockwise by' a spring,

Rotation of shaft 4 (Fig. 1) either by hand crank or motor, rotates cam I which operates through a follower 8 to move the yoke 5 toward the right as seen in Fig. 1 into embracing relationship with a stationary mandrel 9 (Figs. 2, 3 and 6) which mandrel is xed to a frame plate 25 (Fig. 3).

The wire stock I8 (Fig. 1) is then fed either manually or mechanically through a guide channel II in a block I2 and passes between the mandrel 9 (Fig. 2) and the coiling pin I3. The forwardly extending ends 5a of the yoke 5 (Fig. 6) have their upper surfaces cut away to permit feeding of the wire l0 between the yoke and the coil control head I4 (Figs. 2 and 5).

After the ydesired length of wire is fed out, cam 2 (Fig. 1) operates through a follower I5 to move the blade 5 toward the right to out olf the wire ID (Fig. 2). The end of the blade enters a recess I6 in the block I2, and bends over the end of the cut wire. Cam 2 (Fig. l) is designed to hold the blade in its rightmost position as seen in Fig. 2 and retain the out end of the wire in the recess throughout the spring coiling operation.

Cam s operates through a roller I8 to rock the gear segment clockwise about shaft I9. The gear segment 'I drives through the double idler gears 2li and 2I to rotate a Wide pinion 22 (Figs. l and 3). A hub 35 (Fig. 3) of pinion 22 is xed to a hub 23 of the coil control head I4 so that the latter rotates with the former.

The control head I4 and the pinion 22 are freely mounted on the mandrel v9 for rotation by rack 'I as explained above, and may also move axially relative to the mandrel. A fork in the right end of a member 24 (Fig. 3) embraces the hub 23 and lies in an annular groove formed by the top of the control head I4 and the hub 35 of pinion 22. A post 25 (Figs. 1 and 3)', fixed to` the frame plate 26, is provided with a slot With-A in which the member 24 is freely montedgon astud 28. A spring 3| urges member 24 Clockwise against a limit stop 21 (Fig. 3). This ari-"ange-l ment provides a yieldable means for holding the control head I4 and coiling pin in contact with the wire I0.

The rotation of the pinion 22 and the head I4 from the initial position shown in Fig. 2 causes the pin i3 to rotate clockwise and coil the free end of the wire around the mandrel S progressively from the initial position Ia to the positions indicated by the

dotted lines

28, 29, and 30. Between

positions

29 and 30 the free end of the wire must cross over the held end of the wire; therefore, the path of the wire must be controlled to move the free end out of the plane of the held end by the time such crossover occurs. Yoke 5 which serves as a deiiecting member has two surfaces for controlling the path of the wire. Surface 5a (Figs. 5 and 6) is provided to permit the wire to enter between the yoke and the coil control head when the wire stock is fed into 'the machine as previously explained, While surface 5b (Fig. 6) is concave and acts in cooperation with the control head I4 (Fig. 5) to deflect the free end of the wire upwardly in a path which is out of the plane of the held end of the Wire. At such` time, the spring 3! (Fig. 3) holds the control head against the wire and maintains contact between the coiling pin 5 and the wire. It will be noted that the movement of the .free end of the wire from surface 5a to surface 5b occurs between the full line position |50. shown in Fig. 2 and the dotted line positionl 2,8., The camming surface 5b s (Fig. 6) may be designed, how-ever, to cause the deflecting action to occur at any rotated position of the wire, the only requirement being that such deflection occur before the crossover of the ends of the wire. It will be noted further that the camming surface b may be designed to move the free end of the wire in any path, up to the time of cross over, to avoid conict with various parts of the machine.

During the crossover of the wire the free end of the wire which forms the rst convolution of the spring is cammed upwardly by the held end of the wire, and in so doing the spring 3| yields and the control head I4 (Fig. 4) is raised by an amount equal to the diameter of the wire. Dur-- ing the coiling of the succeeding convolutions the free end of the Wire follows each preceding convolution, and the control head I4 yields upwardly throughout the coiling of each convolution of the spring.

1 The wire may be coiled around the mandrel a selected number of times as determined by the displacement of the gear segment l (Fig. l) and the ratios of gears 2B, 2| and 22. A given amount of overdrive of the pin I3 is provided to give the finished spring a permanent set, with the two ends of the spring in a pre-determined angular relation.

When the cams l, 2 and 3 return to the initial position shown in Fig. l, the yoke 5 and the blade 6 are retracted to release the completed spring, and the segment l is returned to its initial position.

It will be noted that the upper lportion of the control head l@ as seen in Fig. 2 is ground away to permit an air jet (not shown) to blow the iinished wire spring off of the mandrel after the yoke 5 is withdrawn. Such means for removing a spring from the mandrel is optional however, and the springs may be removed by any other means or permitted to fall by gravity if so desired, the air jet merely being preferred in the design of the present embodiment.

Normally the completed springs drop off of the mandrel into a receptacle and vbecome entangled with one another and it has been found that the value of time required to untangle the spring often time equals the cost of manufacturing the springs. In the present case, however, the springs are collected on a wire. This is made possible by providing a hollow mandrel 9 (Fig. 4) and passing a wire or rod 32 through the same. Wire 32 is then bent over at either end as shown in Fig. 4 and the air jet drives the completed spring onto the lower end of the wire where the springs are collected. In this manner the springs are prevented from becoming entangled during storage or shipment and may be easily removed from the collector wire when needed for use.

summarizing the present invention provides means for holding the coiling pin in driving engagement with the free end of a length of wire throughout the spring coiling operation. This means comprises (l) a delector member which embraces the mandrel for positive control of the path of the free end of the Wire during the coiling of the rst convolution thereof, and (2) a means which yieldably holds the coil control head and coiling pin against the wire, thereby maintaining the driving relationship during the forming of the first convolution of the wire regardless of the path described by said free end thereof, and regardless of the diameter of the wire, which yieldable means is effective after the forming of said `iirst convolution to hold the wire between the coil control head and the previous convolu-f tion of the wire and maintain said driving rela# tionship throughout the remainder of the spring? coiling operation. As each spring is completed"- and ejected from the machine, a wire or the like" which passes through the hollow mandrel around??- which the spring is coiled, collects the springs toy prevent entanglement thereof.

I claim:

1. In a machine of the class described, the com-y bination of a mandrel around which a spring is to be coiled, a coiling element to revolve about the axis of said mandrel, means to guide spring wire stock between the mandrel and the coiling element, and means operable to hold one end of said wire, with a deflecting member having a surface for controlling the path of movement of the free end of said wire stock, said surface ylosing so formed as to `deflect the free end of thewire out of the plane of the helfl end thereof during the coiling of the first convolution of the spring, a coil control head mounted for rotation with the coiling element during the revolution of the latter about the axis of said mandrel and also mounted for axial movement upon said mandrel, and yieldable means urging said control head axially to press the wire stock against the deecting memoer.

2. In a machine of the class described having a mandrel around which a spring is to be coiled, a coiling element, drive means to revolve said element about the axis of said mandrel, means for guiding spring wire stock between the mandrel and the coiling element, and means operable to hold one end of said wire; the combination of a coil control head mounted for rotation with the coiling element during the revolution of the latter about the axis of the mandrel, a deilecting member having an efective position in which it connes the wire between said control head and the deecting member, a deflecting surface on said member and having such a contour as to deilect the free end of the wire out of the plane of the held end thereof during the coiling of the rst convolution of the spring, with means operable prior to operation of the driving mechanism to move said deflecting member to said effective position, and means operable subsequent to operation of the driving mechanism. to move the deflecting member from said effective position to an ineffective position to release the completed spring from the confinement of said member and said control head.

3. In a machine of the class described having a mandrel around which a spring is to be coiled,

and means for holding one end of a length of wire stock; the combination of a coiling element mounted for axial and revolving movements relative to the mandrel, said element having a driving engagement with the wire during such movements, driving mechanism for revolving said element to coil the wire around the mandrel and in so doing to cause the free end of the wire to cross over theheld end thereof during the coiling of each convolution of the spring upon the preceding convolution, and spring means for restraining the axial movement of said element and yieldable during the coiling and crossover movements of the free end of the wire to maintain said element in driving engagement with the wire throughout the axial and revolving movements of said element.

4. In a machine of the class described having a mandrel around which a spring is to be coiled, a device for holdingone end of a length of wire 7 stock, a coil control head mounted for rotation about the axis of said mandrel, and a coiling element mounted on said control head adjacent said wire and operable to engage the wire during the revolution of the element around the axis of the mandrel with said control head; the combination of, a restraining member movable from a remote position to an effective position adjacent said control head and into Contact with the wire stock to hold the wire against the control head and coiling element during the coiling operation, with releasing means operable at the end of the coiling operation to release said holding device and to remove said restraining member from said effective position to said remote position to thereby release said spring for free axial movement relative to said mandrel, an aperture through said mandrel substantially parallel to the axis thereof, and a spring collecting member inserted through said aperture and effective to receive the comf pleted spring when released from the restraining member and holding device by said releasing means.

5. In a machine of the class described having a mandrel around which a spring is to be coiled, a device for holding one end of a length of wire stock, a coil control head mounted for rotation about the axis of said mandrel, and a ceiling element mounted on said control head adjacent said wire and operable to engage the Wire during the revolution of the element around the axis of the mandrel with said control head; the combination of, a restraining member movable from a remote position to an effective position adjacent said control head and into contact with the wire stock to hold the wire against the control head and coiling element during the coiling` operation, a concave surface on said restraining member to deflect the wire and to cause the free end of the wire to cross over the held end thereof during the coiling operation, and yieldable spring means for allowing relative movement between the coil control head and restraining member in the direction of the axis of the mandrel to allow one convolution of the spring to be coiled upon the preceding convolution, with releasing means operable at the end of the coiling operation to release the holding device and to remove the restraining member from said eilective position to said remote position to thereby release the spring for free axial movement relative to said mandrel, an aperture through said mandrel, and a spring collecting member inserted through said aperture and eiective to receive the completed spring 4when released from the restraining member and hold- 5 ing device by said releasing means.

6. In a machine of the class described having a mandrel around which a spring is to be coiled, a device for holding one end of a length of wire stock, a coil control head mounted for rotation about the axis of said mandrel, and a coiling element mounted on said control head adjacent said wire and operable to engage the wire during the revolution of the element around the axis of the mandrel with said control head; the combination of, a restraining member having a bifurcated end mounted for movement in a plane substantially perpendicular to the axis of said mandrel from a remote position to a position astraddle the mandrel and into contact with the wire to hold the Wire against the control head and coiling element during the coiling operation, and yieldable spring means for allowing relative movement between the coil control head and restraining member in the direction of the axis of the mandrel to allow one convolution of the spring to be coiled upon the preceding convolution, with releasing means operable at the end of the coiling operation to release said holding device and to remove said restraining member from said efective position to said remote position to thereby release the spring for free axial movement relative to said mandrel, an aperture through said mandrel, and a spring collecting member inserted through said aperture and effective to receive the Completed spring when released from the restraining member and holding device by said releasing means.

JACQUES STUSSI.

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

UNITED STATES PATENTS Number Name Date 399,160 Rice Mar. 5, 1889 556,318 Roux Mar. 10, 1896 718,409 Wilson Jan. 13, 1903 `957,203 Gail May 10, 1910 1,078,707 Tevander Nov. 18, 1913 1,212,437 Bates Jan. 16, 1917 1,368,297 Sleeper Feb. l5, 1921 1,831,777 Nunamaker Nov. 10, 1931 1,878,233 DeWald Sept. 20, 1932 2,119,513 Peterson June 7, 1938 2,173,077 Minkel Sept, 12, 1939 2,241,893 Tuttle May 13, 1941 2,442,908 Sirp June 8, 1948 FOREIGN PATENTS Number Country Date 121,073 Australia Jan. 26, 1931 1,288 Germany Dec. 13, 1877