US3575303A

US3575303A - Means for transferring nested coil springs

Info

Publication number: US3575303A
Application number: US810492A
Authority: US
Inventors: Edward M Fischer; Edwin G Krakauer
Original assignee: Kay Manufacturing Corp
Current assignee: Leggett and Platt Inc
Priority date: 1967-07-19
Filing date: 1969-03-26
Publication date: 1971-04-20
Anticipated expiration: 1988-04-20

Abstract

Entire rows of coil springs are successively inserted into a conventional spring assembling machine by an individual unit for each spring of the row. Versatile grippers are operated to approach and recede from the row of springs to grip, invert, advance and rotate the row for the insertion of the entire row simultaneously and in the required position into the assembling machine which receives the row.

Description

3 B l l 4 l 2 position into X m, 6 m w 2 springs are successively ssembling machine by an e row. Versatile grippers e from the row of springs the row for the insertion of References Cited UNITED STATES PATENTS 5/1934 Christensen..................

spring a y and in the required ch receives the row.

9/1934 Shillinger 4/1969 Nowicki 3,438,515 3,232,446 2/1966 Primary Examiner-Gerald M. Forlenza Assistant ExaminerGeorge F. Abraham Attorney-Harry Jacobson ABSTRACT: Entire rows of coil inserted into a conventional individual unit for each spring of th are operated to approach and reced to grip, invert, advance and rotate the entire row simultaneous] the assembling machine whi 214/1, 294/87 B660 l/28 214/1 (B),

= O O 0 o O D COIL oslyn Heights, N.Y.

O O O O 0 SPRING Edward M. Fischer Kew Garden Hills; Edwin G. Krakauer, R [21] Appl. No. 810,492

M 1: 7 6 Division of Ser. No. 654,413, July 19, 1967, Pat. N0. 3,441,064. [45] Patented Apr. 20, 1971 Kay Manufacturing Corp. Brooklyn, N.Y.

l(B2),l(B3),1(B4) SPRINGS 11 Claims, 18 Drawing Figs.

United States Patent [72] Inventors [22] Filed [73] Assignee [54] MEANS FOR TRANSFERRING NESTE [50] Field ofSearch.....................

PATENTED APRZOIQYI 3575303 SHEET 1 0F 4 INVENTORS EDWARD M. FISCHER EDWIN G. KRAKAUER PATENTED APR 20 I971 SHEET 2 (1F 4 INVENTORS EDWARD M FISCHER EDWIN G KRAKAUER ATTORNEY PATENTED m0 m1 SHEET 3 [IF 4 INVENTORS EDWARD M. FISCHER EDWIN G. KRAKAUER ATTORNEY PATENTED APR 20 Ian SHEET 5- UF (i1 INVENTORS EDWARD M. FISCHER EDWIN G. KRAKAUER ATTORNEY MEANS FOR TRANSFER tr NESTED COIL SPRINGS This is a division of application Ser. No. 654,413 filed Jul. 19, 1967, now Pat. No. 3,441,064.

In conventional spring assembling machines for making the inner spring units of mattresses, box springs and furniture cushions, an operator usually inserts one spring at a time until an entire row of springs is formed ready for tying as by a helical tie wire. The operator obtains the springs from a supply of nested springs accumulated by a coiler and separates them manually.

Since the primary function of the assembling machine is to tie the rows together and since the machine cannot perform such function until it has received an entire row of springs, there results a considerable time lag between tying operations or machine cycles which can be considerably reduced by automatically positioning an entire transverse row of springs outside of the machine while the machine ties and advances the previously inserted rows. The preassembled row could then be inserted into the machine immediately after the assembling machine or other suitable receiver for the row has completed its cycle and is cleared for the reception of the newly prepared row.

Various mechanisms have been devised to denest a row of springs preparatory to the insertion of the row into the receiver for the row. One such mechanism is for example, that disclosed in our said US. Pat. No. 3,44l ,064. After denesting or'other ways in which a row of springs is formed, the entire row is advanced to the assembling machine.

The present invention is directed to the provision of an automatic machine which rapidly and efficiently transfers a row of coil springs to a receiver which is arranged in longitudinal spaced relation to the row by means of individual grippers for positively gripping the end coils of the respective springs of the row to grip, invert and advance all the springs of the row simultaneously.

Further objects of the invention include the provision of spring-loaded end coil grippers to grip and releasably lock the top and bottom coils of each spring of the row positively at points spaced circumferentially away from the knots of said coils, thereby insuring accurate positioning and protection of the springs against damage and distortion, the grippers being rotatable about three different axes not only to rotate the gripped spring about the axis of the spring to position the knots as required, but also to swing toward and from each other to compress or to tension the gripped spring and to operate on springs differing in height and otherwise, the grippers being mounted to swing bodily as a unit about a remote axis parallel to the row, enough to invert and advance the spring gripped thereby, the grippers also being given a horizontal reciprocatory movement in proper sequence to the rotary movements.

The above and other objects of the invention will be clear from the description which follows and from the drawings, in which FIG. I is a diagrammatic top plan view of the row arranging and transferring machine showing in dash-dot lines a fragment of the associated spring assembling machine and of some of the grippers in the positions assumed thereby when the transferred row of springs is inserted into the assembling machine.

FIG. 2 is an elevational view of a typical knotted coil spring showing one of the knot-aligning guideways and showing in dash lines, a flared type of end coils, the knots being offset on opposite sides of the spring axis shown in dash-dot lines.

FIG. 3 is a diagrammatical view of one form of a cooperating pair of grippers for the end coils of a longer spring than that of FIG. 2;

FIG. 4 is a step by step diagram of the various positions assumed by the escapement pins at the discharge end of the guideway for each unit.

FIG. 5 is a fragmentary side elevational view of a guideway as well as of a modified form of the grippers and of the mounting therefor, the grippers being shown in the positions wherein the leading spring has been grasped preparatory to its withdrawal, the arrows showing the directions in which the grippers are next moved first linearly and then inverted.

FIG. 6 is a top plan view thereof partly in section and with some parts omitted.

FIG. 7 is a view similar to FIG. 5 but showing the grippers and gripper mounting inverted and about to be again advanced linearly.

FIG. 8 is a plan view of FIG. 7 with some parts omitted, the arrow showing the direction of the succeeding rotation of the grippers and its mounting.

FIG. 9 is a view similar to FIG. 7 with the grippers advanced to the assembling machine and partly closed toward each other to compress the spring and showing the grippers rotated to position the knots preparatory to releasing the spring.

FIG. 10 is a top plan view of FIG. 9.

FIG. II is a combined vertical sectional view and side elevational view of the gripper for the bottom coil of the spring and of part of the gripper-carrying arm.

FIG. I la is a fragmentary front elevational view thereof.

FIG. 12 is a side elevational view partly in section and with parts broken away of the means at each guideway for vertically and horizontally reciprocating the separating and advancing blades for each batch of springs.

FIG. 13 is a fragmentary vertical sectional view transversely through some of the guideways.

FIG. M is a fragmentary top plan view of some of the guideways showing the knot-aligning means therein.

FIG. 15 is a side elevational view of the means for simultaneously and vertically reciprocating all of the individual mechanisms shown in FIG. I2 for operating the blades.

FIG. 16 is a view similar to FIG. 13 of the discharge ends of some of the guideways, showing at the left the outermost or releasing positions of the escapement pins, and at the right, the holding position of the pins.

FIG. 17 is an enlarged fragmentary side elevational view of the lower toothed separating blade of each unit showing the teeth exaggerated in fully meshed position in the spring coils, all of the lower coils of the springs except the parts in contact with the blade being omitted.

In that embodiment of the invention shown by way of example, a batch of knotted and already nested springs as 20 (FIG. 2) of the desired size, shape and wire and such as are commonly accumulated as they leave the coiler, are mechanically or manually inserted into a guideway 21 (FIG. I) of each of a group of units as 22 which are coextensive and are arranged side by side in a transverse row. As has been indicated, in addition to the guideway and the mechanism associated therewith, each unit 22 comprises a pair of

similar grippers

23, 24. The upper gripper 23 engages and temporarily locks therein at the proper time, the top coil 25 of a leading spring 26 at the front end of the batch 27. When the batch consists of knotted as well as nested springs, the end coil is grasped by the gripper at a side point in circumferential spaced relation to the knot. The lower gripper 24 does the same with the bottom coil 28, all as will be explained in more detail hereinafter with respect to the typical unit 22 of the transverse row of such units.

The guideway 21 is long enough to receive and advance batches of a sufficient number of springs to insure the presence of a leading spring at the discharge end of the guideway where the escapement 29 is located, which spring must be ready for the beginning of the cycle of movements of the

grippers

23, 24 in the gripping positions of the grippers and said spring. A suitable sensor (not shown) may obviously be arranged in the gripper to signal and to inactivate the grippers in the absence of a leading spring in the gripping position and to signal and inactivate the grippers should they fail to unlock and release the spring delivered to the assembling machine. Another sensor, such as one of a lever type operating a suitable switch, may similarly and obviously be arranged longitudinally in the guideway to signal and to inactivate the grippers should the batch 27 of springs in the guideway become unduly depleted.

In any case, the guideway 21 is arranged at any convenient slope, but is preferably horizontal and functions to retain groups or batches 27 of knotted and nested springs in position awaiting the arrival of the

grippers

23, 24 at the discharge end of the guideway. Said guideway also functions to accept springs to its capacity in successive batches of any convenient number of springs each, which are randomly loaded into the guideway with the knots thereof approximately preferably forward but unaligned. Through their progress through the guideway, the knots are automatically aligned by the guideway itself to arrange them out of the way of the grippers. The guideway further functions by cooperating with the guideway of an adjacent unit to hold the springs properly while the positive separation and advance of the batch of springs proceeds.

As shown, the guideway is associated with mechanism for advancing the springs in a manner independent of gravity. It comprises an upper horizontal angle member 30 (best seen in FIGS. 12-16) having a horizontal leg 31 and an upright leg 32. Said leg 32 is removably secured to the fixed support bar 33 best seen in FIGS. 14 and 15, to permit the substitution of an angle member of different dimensions to correspond to the different dimensions of springs other than the springs 20. The individual bars 33 extend longitudinally of the guideways and are in turn adjustably connected at the entrance ends of the guideways to the rails 34 (FIGS. and 16) by means of the clamps 35, the rails being fixed to the end frames 36, 37 (FIG. I) of the machine. At the discharge ends of the guideways, the bars 33 are adjustably secured to the fixed support bar 38 by suitable clamps 39. Consequently, the distances between the angle members 30 and the legs 32 thereof may readily be changed to correspond to the diameters of the end coils of the selected springs and to the desired spacing between the springs in the transverse row to be tied, whether the spacing is uniform or irregular.

By making the angle member thin enough, such spacing between the top coils of adjacent springs may readily be reduced to about one thirty-second of an inch.

In order that the upper and

lower knots

40, 41 of the batch 27 be aligned out of the way of the grippers, the horizontal leg 31 of the angle member is tapered outwardly from a point at the entrance end of the guideway to about the halfway point of its length to form the aligning edge 42 (FIGS. 1 and 14) which enters the exterior angular space or notch at the knot and urges the knot circumferentially around the axis of the spring as the spring advances. With respect to the lower coil 28, the leg 48 of the lower angle member 44 enters the notch at the knot 41 whereby the inclined edge of said leg 48 serves to position said knot. The vertical leg 43 is supported by a bar 33 in the same manner as is the upper angle member 30. Frequently, as shown in FIGS. 2 and 3, the

knots

40 and 41 are not in vertical alignment with each other, but the

inclined edges

42 and 48 rotate the springs enough to one side to arrange them out of the way of the grippers. It will be understood that each of the units 22 is substantially symmetrical about the horizontal middle plane thereof, the lower half being of parts identical with those of the upper half except for the angle members of the guideway. It will also be noted that a pair of adjacent vertical legs of the upper angle members 30 are in contact with and guide and constrain opposite sides of the upper coils of the spring batch. Similarly, the upright legs 43 of adjacent lower angle members 44 guide the lower coils 28.

Adjustment of the spacing between a pair of upper legs 32 and also between a pair of adjacent lower legs 43 to accommodate end coils of different diameter, is easily attained by merely loosening the

clamps

35 and 39 and moving them to the required positions along the rails 34 and bars 38 respectively. Since the

angle members

30 and 44 are removably attached to their supports 33, said members may readily be replaced by others of different dimensions, especially of the horizontal legs, as required when changing to different springs. Adjustment of the spacing between the springs of a row can be attained as above described and by removal of selected angle members and their supports from certain guideways and the substitution of upright plates as 45 in the required space relation to the retained angle members. Each plate 45 is attached to an auxiliary longitudinal bar 46 which in turn is fastened with the spacer therebetween to the adjacent support bar 33.

Associated with each guideway of the unit and constituting the means for separating and initially advancing the batch of springs and preventing overloading and packing of the guideway, are the upper and lower similar

toothed blades

50 and 51 respectively (FIG. 12). The teeth 59 thereof are generally triangular (FIG. 17) and sufficiently sharp to be easily wedged between end coils of the springs. As shown in FIGS. 12 and 15, the blades are moved in unison in the same direction through what is normally a substantially rectangular path, first up, then forward, then down, then back to the starting positions. However, a yieldable takeup or lost motion connection to the actuating means for the blades prevents forward motion of the blades when such motion is sufficiently resisted, as in the case of overloading, jamming, breakage or the like. For this purpose, each blade has guide lugs 53, 54 projecting from the side thereof, the lugs being inserted into the elongated slit 52 in the plate 55, the plate being mounted for both vertical and horizontal reciprocation. Between the end wall of the slot 52 and the adjacent end of the lug 53 is interposed the compression spring 56 which urges the blade toward the right as viewed in FIG. 12 into its forwardmost position relatively to the plate 55. Suitable screws as 57 (FIGS. 12 and 13) passing through the guide plate 58 and into the plate 55 secure the blades to said plate 55 while permitting only horizontal movement of the plate 55 relatively to the blade in both directions when movement of the blade 55 is effectively resisted.

Said plate 55 is driven by the outer reciprocating plate 60 to which it is operatively connected by the torsion springs 61, 62, the springs urging the two plates apart. The rollers 63 on the riving plate 60 operate in the inclined slots 64 in the driven plate 55, and when held by the springs 61, 62 at the outer ends of the slots, prevent relative movement of said plates, and assure vertical movement of the plates in unison until the blades enter and are meshed with the coils of the batch of springs and vertical movement of the blades is consequently halted. Continued vertical movement of the driving plate in the same direction earns the rollers toward the inner ends of the slots and thereby moves the driven plate 55 and the blades connected thereto forwardly to advance the springs engaged by the blade teeth.

On the first part of the return vertical stroke of the driving plate 60, the driven plate also moves vertically under the pull of the springs to retract the blade teeth from the coil springs of the batch. When the blade teeth have been completely freed of the end coils of the springs during the last part of the outer vertical movement of the driving plate, then the rollers 63 move to the outer ends of the slots 64 to move the freed driven plate 55 and the blades back to the positions shown in FIG. 15.

Connected to the plate 60 in each guideway as by the bolt 65 is an adjustable connecting bar 66 movable along the reciprocating rails 67 to the required position in the guideway (FIGS. 1, I2 and 13). As shown in FIG. 15, said rails 67 for actuating the upper and lower blades are secured by the clamps 68 to the same reciprocating frame 69 arranged outside of the machine frames 36, 37. In this form of drive, all rails 67 reciprocate together so that the upper blades 50 are all retracted while the lower blades 51 are meshed with the coils. It will be understood, however, that the

blades

50 and 51 may obviously be so driven as to reciprocate in opposite directions to mesh with the end coils at the same time and to act together to advance the coils at the same time. This may obviously be done by separating the frame into two parts, an upper part 6% and a lower part 69b. One set of connecting rods 70 are shown in FIG. 15 as fixedly connecting the frame parts 69a and 6%, but obviously a separate pair of such rods may be used for each of said parts to operate in the bearings 7-1 (FIGS. 1 and projecting from the machine frames 36, 37, and the part 69b and the members connected thereto may be suitably counterbalanced. The cam follower 72 of the frame part 69a is shown in engagement with the high part of the cam 73 while the corresponding cam follower engages the low part of the cam to move the rigid frame 69. However, a second cam, identical with the cam 73 may be mounted on the common shaft 74 so that both cam followers are at the high parts of the respective cams at the same time and both at the low parts of the cams at the same time as would be permitted by the duplication of the cams and connecting rods.

A suitable motor 75 drives the cam shaft 74 through the pulley 76, chain 77 and suitable sprocket wheels. The frame 69 and its operating mechanism is duplicated at both ends of the machine as shown in FIG. 1. The frequency of reciprocation of the frame 69 is such that a leading spring 26 is always in place at the discharge end of the guideway and in the gripping position when the

grippers

23, 24 are also in the gripping position. When advance of the batch of springs is sufficiently resisted as hereinbefore indicated, the blades merely reciprocate vertically, the spring 53 yielding in the slot 52 and the blade teeth maintaining the coil springs in predetermined spaced relation.

In FlG. 1 is diagrammatically shown the steps in the operation of the escapement 29 which acts as a releasable stop to engage the leading spring 26 and to hold back the remainder of the batch 27 including the succeeding spring 80. The escapement also acts in the proper sequence to release only the leading spring for advance by the grippers, then to permit the advance of the succeeding spring to become the leading spring in turn. The rear parts of the top and

bottom coils

25 and 28 usually overlap the respective front parts of the top and bottom coils of the succeeding spring 81) as the springs advance in the guideway (FIGS. 5, 6 and 14). While in such overlapped position, a pair of escapement pins are reciprocated to enter and leave the coils, by means of the respective rails 83 and running the length of the machinebetween the

frames

36 and 37, and suitably reciprocated in opposite directions to each other by the respective air cylinders b6 and $7. The escapement pins are adjustably secured to the rails by the clamps 65 (FIGS. 12 and 16).

In FIG. d, the cross sectioned circles merely represent the end coils diagrammatically, it being intended to show how the pins come into contact with the foremost and rearrnost parts of said coils at the overlap, alternately to hold them against advance and to release them. When the pin 31 is in the inner of its positions as shown at A, FIG 4, to hold back the spring which has become the leading spring, the pin 32 is in its outer or releasing position of the spring 311, and about to move inwardly into the position shown at B. At position B, both springs 26 and 911 are momentarily held back, the pin 81 moving outwardly into position C as soon as the pin 82 has reached its holding place. At position C, the pin 81 has moved out to release the spring 26 which is grasped by the grippers and withdrawn whereatter the pin 81 moves inwardly into position D to block the succeeding spring 911 while the pin 82 moves outwardly to make way for said spring to reach and to be halted by the pin 111, as shown at position E. The arrows at position E show the direction of movement of the springs which bring them back to position A ready for the repetition of the operation.

To reciprocate the escapement pins, the rails 83 are suitably reciprocated in sequence with the operation of the grippers 213, 2 1 by the air cylinders 96 while the rails are similarly reciprocated by the similar air cylinders 87.

The grippers 23, M for each unit are quite versatile. Each is so mounted as to be made to swing about three different axes, one as represented by the gripper pivot pin 91) (H0. 11) extending into the gripper carrying arm 91, a second being the axis about which said arm is swung and a third being the axis about which said arm and the parts carried thereby are inverted, as will be more fully described hereinafter. In FIG.

11 is shown the lower gripper 24 and its gripper arm, but it will be understood that the upper gripper and its mounting are substantially identical with the lower shown except for the positions thereof in the assembled gripping mechanism.

Each gripper comprises a hollow casing 92 in which is pivoted the lever 94 by means of the pin 93. Said lever carries at its rear end the latching pin 95 and at its front end caries the diaphragm engaging member 96. A suitable spring 97 urges the latching pin 95 into its coil-latching position and also urges the member 96 against the diaphragm 98 stretched across the opening 99 in the casing. Said opening is closed at one end by the cover plate 100 and is closed at the other end by the cover plate 101 for the casing, said opening communicating with a source of compressed air through the inlet 102. Part of the rear end portion of the casing 92 is beveled to provide the flared coil-receiving recess 103 into which the latching pin 95 projects, said pin being long enough to enter the hole 104 in the cover plate 101 forming one side of the recess 103 until removed by the lever to unlock the captive coil.

To rotate the gripper about its pivot 90, a suitable grooved pin 105 is fixed to the casing and receives in the circumferential groove thereof, a screw 106 which engages a connection to the reciprocating operating rod 107 for all the grooved pins 1115 of the various grippers. To operate said rod (FIG. 1), adjustable stroke air cylinders 103 are operated during the advance of the grippers. The stroke limit stop out 124 controls the gripper rotation to position the spring as desired in the assembly machine. Said cylinders are provided with aligning joints connecting them at one end to a bracket fixed to the transfer bean 109 and at the other end to the rod 107 thereby permitting the grippers to be given the various movements required.

In the coil gripping position of the grippers shown in FIGS. 5 and 6, they have been swung about their respective pivots to reach for the end coils of the leading spring in the guideway on the side opposite to the knots of the coils and the end coils have entered the recesses 103. The lever 94 can be cammed out of the way of the coils by the action of the coils on the latching pins or be opened by air pressure through the inlet 102. After passing the latching pins, the coils are locked at the ends of the recesses by said pins as the spring 97 acts to return the levers and the pins carried thereby to the coil-locking positions thereof shown FIG. 11. It should be understood that while the grippers are shown in FIG. 5 in a substantially horizontal position for ease of illustration, such position is neither necessary nor normal and depends largely on the overall length of the spring which is advanced. In FIG. 3 the gripper arms 191 and the grippers carried thereby have been spread apart to the limit permitted by the adjustable stops 111 associated with the transfer beam 109, by the spring between the gripper arms. Said stops are mounted on the holder 112 for each unit. The holder is adjustablysecured to the T-beam 109 extending throughout the length of the machine, by the clamps 113. The

gripper arms

91 or 191 are themselves mounted on the shaft 114 which is supported by the side plates 115 secured to the holder 112 (FIGS. 5 and 11a). Each gripper arm terminates in a hub 116 extending about halfway across the supporting shaft 114 as best seen in FIGS. 6 and 11a.

The transfer beam 109 oscillates about in each direction in timed relation to the operation of the grippers and also reciprocates linearly in the proper sequence as it moves between the guideways and the assembling machine. Said beam terminates in, and is supported at each end by, a short shaft 117 (FIG. 1) which is rotated by a suitable rotary air cylinder 123 of a well-known type and is mounted in the carriage 11% carrying the wheels 119 which roll on the track 1211. Said carriage is linearly reciprocated by the air cylinder 121 through the desired stroke at the proper time to advance and retract said beam as well as the grippers carried thereby and the entire row of springs held by the grippers, thereby to transfer the springs and to insert them into the assembling machine 122.

It is the rotation of the grippers and the transfer beam about the axes of the shafts 117 from the position of FIGS. 5, 6 to that of FIGS. 7, 8 during the advancing movement of the beam, which enables the interposition of the grippers between the guideways 21 and the receiver 122 for the row of springs. Such rotation together with the linear motion of the transfer beam reduces the space needed for the transfer mechanism, while the additional rotation of the grippers about their pivots 90 constituting other axes of rotation, permits accurate control of the positions of the knots of the springs, the further partial rotation of the gripper arms around their shafts 114 enabling not only the adjustment of the grippers to springs of various lengths but also pennitting the grippers to compress or extend the springs of the row for the proper insertion thereof into their exact required positions in the assembling machine for tying by said machine.

After the grippers have grasped the leading springs 26 in the guideways, the air cylinders 121 are actuated to advance the transfer beam 109 linearly sufficiently to withdraw the row of said springs from their guideways. Then during such advance, the rotary air cylinder 123 are actuated to rotate the beam about its shafts 117 from the position of FIG. to that of FIG 7 thereby inverting the row of springs held by the grippers and also inverting the grippers. During the continued linear advance of the transfer beam in its inverted position, the grippers are rotated through the rods 107 about their pivots 90 sufficiently to bring all of the

knots

40 and 41 to a position at one side of the end coils as shown in FIG. out of the way of the tying helical of the assembling machine. The final linear advance of the transfer beam causes the gripper to enter the flared entrance spaces 121 of the assembling machine and to move inwardly toward each other and compress the springs in the row as said spaces decrease in height. As best seen in FIG. 9, the greater potions of the end coils are firmly held in somewhat compressed condition by the assembling machine and all that is needed to repeat the cycle of operations is to release the latching pins 95 from their locking positions and to retract the freed grippers to the gripping positions thereof.

Such release is accomplished by means of suitable valve connected to the air duct 102 of each gripper. The valve is automatically opened immediately after the row of springs has been positioned properly in the assembling machine, thereby introducing compressed air through the opening 99 against the flexible diaphragm 98, which yields to swing the lever 94 against the action of the spring 97 to retract the latching pin from the recess and to free the grippers from the end coils of the springs, for their return movements by the action of the air cylinders 121 on the transfer beam. The various return movements of the beam, gripper arms and grippers proceed in inverse order and reverse directions from the transferring movements above described.

During the movements of the grippers back to their gripping positions, the separation and advance of the nested springs in the guideways and the replenishment of such springs in batches, go on independently of the transfer and return movements of the grippers, though the escapement pins 81 hold back all the springs (FIG. 4A). The arrival of the grippers at the guideways causes the escapement cycle to begin after the latching pins 95 have been retracted by air pressure through the air inlet 102. The end coils therefore enter the recesses 103 of the grippers, past the latching pins 95 which are held out of the way of said end coils until the end coils have passed, the pins coming to rest in front of said coils under the pressure of the springs 97 when the air pressure has been exhausted, thereby to lock the coils in place against dislocation, distortion or damage.

Since the design of the circuits controlling the actuation of the various air operated parts is well within the skill of those familiar with such circuits. and include such well-known devices as sensors, solenoid valves, switches, relays, magnetic clutches and the like, such circuits and devices have not been illustrated or described in detail.

While certain specific forms of the invention have herein been shown and described, various obvious changes are contemplated and may be mad therein without departing from the spirit of the invention defined in the appended claims.

We claim:

1. In a machine for transferringa row of coil springs to a receiver for the row, gripper means for each spring of the row to grip and to release a spring, and gripper operating means for moving the gripper means to invert the spring end for end and to advance the spring toward the receiver, the gripper means comprising a gripper for each spring, a lockable latch in each gripper for retaining a coil of the spring in its gripper and means to unlock the latch to release the coil for withdrawal from the gripper, the gripper operating means rotating and also reciprocating the gripper means.

2. The spring row transferring machine of claim 1, the gripper operating means rotating each gripper about a pair of axes perpendicular to each other and also about a third axis remote from the grippers and extending transversely of the machine.

3. The spring row transferring machine of claim 1, the end coils of the springs having knots therein, the latch of each gripper gripping one of the end coils, the gripper operating means rotating each gripper in a curvilinear path to position the knots at points in predetermined circumferential spaced relation to the initial positions of the knots.

4. In a machine for transferring to a receiver a row of coil springs, gripper means for each spring of the row adapted to enter, to grip and to release a coil of each spring and gripper operating means to control and to impart sequential linear and curvilinear movements to said gripper means in successive advancing and retracting strokes, first to advance the gripper means linearly for a predetermined distance, the to invert while further advancing the gripper means, then to further advance the gripper means linearly thereby to complete the advancing stroke and to insert the row of springs into the receiver, then on the retracting stroke to retract the gripper means linearly for a predetermined distance, then to reinvert while continuing the retraction of the gripper means and then to retract the gripper mans further linearly through a predetermined stroke to the point of the beginning of the linear advancing movement.

5. The spring row transferring machine of claim 4, the gripper means comprising a pair of similar grippers facing each other, a common pivot for said pair of grippers, the gripper operating means including means to swing the grippers toward each other about said pivot to compress a spring held between the pair of grippers and to swing the grippers away from each other to release said spring and thereby to permit said spring to expand.

6. The spring row transferring machine of clam 5, each of the end coils of the spring having a tying knot therein, each of the grippers having a second pivot, the gripper operating means including means for rotating the grippers simultaneously about the respective second pivots therefor thereby to change the angular positions of the knots relatively to the line of movement of said second pivots prior to the insertion of the row of springs into the receiver.

7. The spring row transferring machine of claim 4, the gripper operating means including a support beam for the row of gripper means and also including mechanism for automatically imparting to said beam said sequential linear and curvilinear movements.

8. The spring row transferring machine of claim 4, the gripper means comprising a lockable latch for each end coil of each spring of the row and means to unlock the latches to release the row of springs to permit expansion of the springs and for withdrawal of said row of springs from the gripper operating means at the end of the movement of the gripper means toward the receiver and prior to the retraction of the gripper means.

9. The spring row transferring machine of claim 4, the gripper operating means including a beam parallel to and carrying the row of gripper means and constituting the inversion axis of the gripper means, mechanism to rotate the beam to swing the gripper means from one side to the opposite side of said beam and mechanism to move the beam linearly during the end portions of the advancing and of the retracting movements of the gripper means.

10. The spring row transfering machine of claim 4, the gripper means comprising a latch, a casing for the latch having an entrance recess for the reception of that part of the end coil of a spring in circumferential spaced relation to a knot of the end coil, the latch comprising a movable member in the casing extending into the recess and carrying a latching pin and urged into a coil-locking position across the recess and into the path of withdrawal of the end coil from the recess, and means to unlock the latch comprising means to move said member in a direction to withdraw the pin out of said path after the transfer of said row of springs to the receiver.

11. In a machine machine transferring a row of coil springs to a receiver for the row, gripper means for each spring of the row entering, gripping and retaining releasably a coil of a spring, and gripperoperating means expansion reciprocating the gripper means toward and from the receiver in a path in part substantially linear and in part curvilinear to invert the gripper means and the row of springs end to end and to retract and thereby to reinvert and to reverse the movement of, the gripper means along said path after the row of springs has been released by the gripper means, the gripper means being interposed between the row of springs to be transferred and the receiver for the row and each comprising a pair of arms swingable toward and from each other and each carrying a lockable latch adapted to grip and to release an end coil of a spring, the gripper operating means including a pivot for said arms.

Claims

1. In a machine for transferring a row of coil springs to a receiver for the row, gripper means for each spring of the row to grip and to release a spring, and gripper operating means for moving the gripper means to invert the spring end for end and to advance the spring toward the receiver, the gripper means comprising a gripper for each spring, a lockable latch in each gripper for retaining a coil of the spring in its gripper and means to unlock the latch to release the coil for withdrawal from the gripper, the gripper operating means rotating and also reciprocating the gripper means.

11. In a machine machine transferring a row of coil springs to a receiver for the row, gripper means for each spring of the row entering, gripping and retaining releasably a cOil of a spring, and gripper operating means expansion reciprocating the gripper means toward and from the receiver in a path in part substantially linear and in part curvilinear to invert the gripper means and the row of springs end to end and to retract and thereby to reinvert and to reverse the movement of, the gripper means along said path after the row of springs has been released by the gripper means, the gripper means being interposed between the row of springs to be transferred and the receiver for the row and each comprising a pair of arms swingable toward and from each other and each carrying a lockable latch adapted to grip and to release an end coil of a spring, the gripper operating means including a pivot for said arms.