US3688918A

US3688918A - Stacking device for coil springs

Info

Publication number: US3688918A
Application number: US51455A
Authority: US
Inventors: Walter O Spuhl
Original assignee: Spuehl AG
Current assignee: Spuehl AG
Priority date: 1970-01-17
Filing date: 1970-07-01
Publication date: 1972-09-05
Anticipated expiration: 1989-09-05
Also published as: DE2002006B1; DE2002006C2

Abstract

A stacking device for helical coil springs which have a final coil at each end that terminates in a knot. The stacking devices is of the type having a frame with side walls and a floor defining a guide channel to which the coil springs are supplied by a transfer arm and within which the coil springs are advanced forwardly for stacking. The coil spring is received by rigid converging guide flaps which slightly compress the coil spring. Slide bars are provided which are reciprocally movable on the frame longitudinally of the guide channel. A pair of advancing plates are carried on the slide bars and are spaced inwardly of the guide channel side walls for receiving the coil spring in slightly compressed condition from the guide flaps. The slide bars are operative following reception of the coil spring by the advancing plates to move the advancing plates rearwardly causing the coil spring to slide off the advancing plates and expand axially for engagement with the guide channel side walls whereupon the slide bars are operative to move the advancing plates forwardly so that each of said advancing plates engages the knot in the final coil at the associated end of the coil spring to simultaneously partially rotate and advance the coil spring into stacking relationship with the preceding coil spring. Alignment means are provided including a normally raised striking element operative when the coil spring has been advanced into stacking relationship with the preceding coil spring to move downwardly against the coil spring urging the coil spring into contact with the floor of the guide channel.

Description

. United States Patent 1151' 3,688,918 Sept-5, 1972 Spiihl [72] Inventor: Walter O. Spiihl, St. Gallen, Switzerland v [73] Assignee: Spuhl AG, St. Gallen, Switzerland [22] Filed: July 1, 1970 [21] App]. No.: 51,455

[30] Foreign Application Priority Data Primary Examiner-Robert J. Spar Attorney-Wm. Marshall Lee and James B. Blanchard [57] ABSTRACT A stacking device for helical coil springs which have a final coil at each end that terminates in a knot. The

, stacking devices is of the type having a frame with side walls and a floor defining a guide channel to which the which the coil springs are advanced forwardly for stacking. The coil spring is received by rigid converging guide flaps which slightly compress the coil spring. Slide bars are provided which are reciprocally movable on the frame longitudinally of .the guide channel. A pair of advancing plates are carried on the slide bars and are spaced inwardly of the guide channel side walls for receiving the coil spring in slightly-compressed condition from the guide flaps. The slide bars are operative followingreception of the coil spring by the advancing plates to move the. advancing plates rearwardly causing the coil spring to slide off the advancing plates and expand axially for engagement with the guide channel side walls whereupon the slide bars are operative to move the advancing plates forwardly so that each'of said advancing platesengages the knot in the final coil at the associated end of the coil spring to simultaneously partially rotate and advance the coil spring into stacking relationship with the preceding coil spring. Alignment means are provided including a normally raised striking element operative when the coil spring has been advanced into stacking relationship with the preceding coil spring to move downwardly against the coil spring urging the coil spring into contact with the floor of the guide channel.

7CIaims,9DrawingFigures' Patented Sept. 5, 1972 4 Sheets-Sheet 1 Patented Sept. 5, 1972 4 Sha na-Sheet 2 Patented Sept. 5, 1972 Q 4 Sheets-Shoat 3 Patented Sept. 5,1912 3,688,918

4 Sheets-Sheet 4 I I STACKING DEVICE FOR COIL SPRINGS The invention concerns a stacking device for coil springs which have final coils that end in knots, the machine having a guide channel for the coilsprings which are automatically supplied with the knot lying on top, a slide bar which can be moved backwards and forwards in the guide channel and which is provided with advancing plates on both sides, an element which can be moved up and down in time with the slide bar movement approximately perpendicular to the plane in which the springs advance and which acts upon at least one of these, and also means in addition in order to ob tain a rotation of the knots by about 90 while making use of a coil guide caused by the springs which have already been stacked. Such a device has been shown in the German Pat. No. 1,241,403 by the same applicant. In the case of the well known device, the element which can be moved up and down has an oblique edge at the bottom which comes into contact with the knot of the one final coil of the spring which is supplied in the course of the downward motion of the element and thereby causes the rotation which screws in the spring into the springs which have already been stacked. The present invention has the object of improving and simplifying this device which was already very progressive compared to the earlier state of the art, namely with respect to an even tighter stacking and an even more reliable method of operation, particularly for the case that the springs are not sufficiently-free of defects. This is accomplished according to the invention by means of the fact that the final coils of the springs which at that moment are being supplied to an operating cycle are supported in the guide position on the advancing plates from which they slide off in the course of a backward movement of the slide bar whereupon they come to rest partially upon parts of the rigid frame and partially overlapping onto the final coils of the immediately preceding springs, while the body of the spring which is being supplied is still held in the supply position and that in the course of the forward movement of the slide bar which then follows, the front edges of the two advancing plates carry along the knots of the two final coils of the supplied springs which project toward the inside and thereby effect both the complete advance of the supplied springs in the guide channel as well as the rotation of the knots and that in addition, the element which can be moved up and down has a pressure foot in order to press down the immediately preceding spring onto the floor of the guide channel by means of striking upon at least one of its final coils during the operating cycle which is being considered. Therefore, the rotation is caused simultaneously on the knots of both final coils of the springs which are supplied and without any increased effort.

On the contrary, the advancing plates can now consist simply of a sheet of constant thickness and not, as previously, be made of relatively thick plates which are worked into a wedge shape.

Additional characteristics and advantages of the invention will be seen from the following description as well.

An exemplified embodiment of the object of the invention is shown schematically in the drawings. The drawings show the following:

FIG. 1, a longitudinal cross section through the stacking device in the vertical midplane of the guide channel in a first phase of its operating cycle,

FIG. 2, a portion of the device in a top view corresponding to FIG. 1,

FIG. 3, a portion of the device in a side view corresponding to FIG. 1,

FIG. 4, the same longitudinal section as in FIG. 1, but in a second operating phase,

FIG. 5, a portion of the device in a top view corresponding to FIG. 4,

FIG. 6, the same longitudinal cross section as in FIG. 1, but in a third operating phase,

FIG. 7, a portion of the device in a side view corresponding to FIG. 6,

FIG. 8, the same longitudinal cross section as in FIG. 1, but in a fourth operating phase, and

FIG. 9, a cross section according to line IXIX in FIG. 8.

In order to simplify the comparison, the same reference signs are used in the drawings for the corresponding parts as in the patent which was mentioned at the beginning.

The stacking device has a guide channel 1, the floor of which is formed by a base plate 2 which is attached rigidly to the frame, while its side walls, of which only one is shown in FIGS. 3 and 7, each have two

horizontal rods

3 and 4 which are parallel to each other. The rods of each side wall which are attached rigidly to the frame are connected with the base plate 2 and with each other at their right ends on the outlet side in FIG. 1 by one vertical post 5 each which is mounted externally on these rods and which has been omitted in FIGS. 3 and 7. At the left end of each pair of

rods

3 and 4, on the inlet side, a vertical, rectangular metal plate 7 is attached on the inside of the pair of rods over two vertical metal strips 41. An edge 42 on the right side (see FIG. 2) of plate 7 is bent slightly toward the

rods

3 and 4 corresponding to the thickness of the strips 41. However, plate 7 can also be fastened directly to

rods

3 and 4, in which case the inclined edge 42 is unnecessary. Two guide flaps 9 which diverge downward are provided below plates 7 and are fastened to rods 3 by means of flanges 43. which are bent around horizontally so that the upper edge 44 of the guide surface of flap 9 projects toward the inside somewhat beyond plate 7.

The guide flaps 9 serve to guide the two final coils 10 of a double-cone coil spring 11 which is held at its midpoint by the free end of an arm 12 of the transport device, for example, by means of a hook which has not been shown. The arm supporting the spring 11 rotates in a counterclockwise direction to FIG. 1 and thereby brings the spring in between the two guide flaps 9 by means of which the spring is lightly pressed together. In the course of further rotation of the arm, the final coils 10 of the spring 1 1 glide over the edges 44 onto two advancing plates 21 which belong to a slide bar 14.

means of a vertical strip 45 and at their ends on the right side by means of a vertical strip 46. A small block 20 is fastened above rod 15 on strip 45 and supports the plate 21 which has already been mentioned.

Strips

45 and 46 are located on the outside of the

rods

15 and 16 and, in contrast to a connection strip previously attached to their insides, do not participate in the progression of the springs 11 in the guide channel. On each side of the slide bar 14, two guides 23 shown only in FIGS. 4 and are shown between which there is a roller 24 which is mounted on the end of a lever 25 belonging to the transport device, the lever being moved periodically back and forth in the sense of the double arrow 26, whereby the slide bars 14 are shifted back and forth in the sense of the double arrow 27 along

rods

3 and 4.

In order to press down the springs 11 which are advanced forward in the guide channel by the slide bar 14 in a way which will be explained in more detail below and stacked in each other, a rocker arm 29 is provided which is provided at one end with a bearing eye 30 which is supported so that it can be moved on an offset peg 31 which is located at the upper end of the post 5 which is shown. A feeler roller 32 is attached to the rocker arm 29 by means of a screw 33, the bolt of which is cut 011' smoothly and upon which roller 32 can rotate. A pin 34 is screwed tight to the rocker arm 29, and the upper end of a tension spring 35 is fastened to the free end of the pin 34; the lower end of the tension spring, which is not shown, is fastened to the frame. The tension spring 35 holds the feeler roller 32 in contact with a profile cam 36 which is fastened to the upper rod which is visible in the figures and which has two

horizontal cam surfaces

36a and 36b which are present through a cam surface 360 falling in the advance direction of the springs l 1. It can be seen that the rocker arm 29 is movedup and down in the sense of the double arrow 37 by means of the movement of the slide bar 14 back and forth.

A plate 38 is fastened to the free end of rocker arm 29 and, by means of screws 47 which go through the adjustment slot 48 provided in plate 38, are fastened to the adjustment slot. In contrast to the previous case, plate 38 does not have any edge on its lower side which can grasp a knot 28 present in a final coil 10 of the spring 11 in question in order to rotate the knot into a position which is suitable for tight stacking of springs 11 and thereby screw in" this spring into the springs which have already been stacked. Instead of this, a bottom edge strip 49 has been bent out of the plane of plate 38 so that it forms a-pressure foot which, in the course of the downward movement of rocker arm 29, strikes upon the final coil 10 of the spring 11 which is in question and has already been moved forward and screwed into the preceding spring and presses the spring in question down to the floor 2 of the guide channel 1.

In the following section, the manner of operation of the device which is described will be explained in even greater detail.

As already mentioned above, the final coils 10 of the spring 11 which is held by the transport arm 12 and slightly compressed by the guide flaps 9 in the supply position according to FIGS. 1-3 first reach the slide plate 21 and not, as previously, the plates 7 which are fastened rigidly to the frame. The slide bar 14 which is operated by levers 25 through the rollers 24 and the guides 23 now moves from its initial position, not forward as previously, but backwards, that is, according to arrow 50 in FIG. 1 opposite to the direction of advance in the guide channel 1. In the course of this, spring 1 1 is still held tightly by arm 12 which remains in its position so that the final coils 10 finally slide off the slide plates 21 onto the plates 7 which are attached rigidly to the frame and thereby each come to lie overlapping on their right side on the left side of the corresponding final coil 10 of the preceding spring as is shown in FIGS. 4 and 5.

Of the springs 11 already located in the guide channel 1, only the final coils 10 with the accompanying knots 28 are represented in the drawings for the sake of clarity.

If the slide bar 14 now moves toward the front according to arrows 51 in FIGS. Sand 6 starting from its final position at the left, then its front edge 52 strikes upon the final coil 10 on the knot 28 ofspring 11 which projects inward from the final coil 10, the body of which is still located in the supply position, and thereby moves this forward in the guide channel or into the stacked springs which are already in the supply channel. By means of guiding the springs which are already stacked, the new spring will be screwed into these in the course of this, whereby knot'28 which is lying toward the top in the initial position is rotated by almost into the position of the knot designated with 28, in FIG. 1. It can therefore be seen that the edge 52 of the slide plate 21 surprisingly not only causes the advance of spring 11 but also the rotation of the knots which is required for tight stacking. For these functions, according to the patent which was mentioned at the beginning and which already provided great simplification compared to earlier technology, it was still necessary to have a slide bar 14 that acted upon the springs with two stages 7, 19 in two successive operating cycles and an oblique edge 38a of a plate-shaped element 38 which could be moved perpendicularly to the plane in which the springs were advanced, whereby the reference numbers given in parentheses refer to the drawings in the above mentioned patent. To be sure,

the present stacking device also has the plate 38 which can be moved up and down and which has a movement mechanism that is very similar to that of the previous plate-shaped element 380. However, plate 38 is not provided with an edge which is suitable for rotating the knots, but rather with a pressure foot 49 which, for example, could also be attached to the lower end of a vertically positioned rod. During the operating cycle under consideration, pressure foot 49 presses upon the final 'coil 10 of the spring which has advanced last and possibly also upon the final coil of the additional previously advanced spring on the floor of the channel as is shown in FIG. 4. This guarantees a very compact stacking of the springs which is corrected perfectly even in the vertical direction and even in the case of springs which have a diameter of the final coil that varies within a relatively large range.

The new stacking device stacks more compactly and, above all, more reliably than the previous stacking device, whereby the circumstance that the knots on both final coils of the springs are rotated and not only one of them is rotated has a favorable effect. In addition, the stacking is also perfect when the springs have defects, for example, as a result of deficient quality in the wire which was used or they have final coils which do not lie in planes exactly perpendicular to the axis of the spring because of incorrect adjustment of the spring manufacturing apparatus.

Finally, the construction of the slide bar is also more simple because the slide plates are simply punched sheet metal plates while relatively heavy tapered plates were provided previously which had to be processed on one side and were therefore considerably more expensive to acquire. This tapering which was necessary in order not to hinder the supply of springs received by the transport arm before the slide bar had reached its final position at the inlet side is naturally superfluous in the case of the device which is described.

What is claimed is:

1. In a stacking device for helical coil springs which have a final coil at each end that terminates in a knot, the stacking device being of the type having a frame with side walls and a floor defining a guide channel to which the coil springs are supplied by a transfer arm in an orientation with the knots on top and within which guide channel the coil springs are advanced forwardly for stacking, the combination with said frame comprismg:

entrance means affixed to said frame for receiving and slightly compressing a given coil spring being supplied to said guide channel on said transfer arm;

slide means reciprocally slidable on said frame longitudinally of said guide channel; and

a pair of advancing plates carried by said slide means and spaced inwardly of said guide channel side walls to receive said given coil spring on said transfer arm from said entrance means, said slide means being operative following reception of said given coil spring on said transfer arm by said pair of advancing plates to move said advancing plates rearwardly causing said given coil spring to slide off said advancing plates and expand for engagement with said guide channel side walls to permit release of said given coil spring by said transfer arm whereupon said slide means is operative to move said advancing plates forwardly so that each of said advancing plates engages the knot oriented at the top of the final coil of said given coil spring at the associated end of said given coil spring to simultaneously partially rotate and advance said given coil spring into stacking relationship with the preceding coil spring.

2. The combination defined in claim 1 further comprising alignment means including a normally raised striking element movable in a vertical plane, said alignment means being operable when said given coil spring has been advanced into stacking relationship with the preceding coil spring to cause said striking element to move downwardly against said given coil spring urging said given coil spring downwardly into contact with the floor of said guide channel.

3. The combination defined in claim 2 wherein said striking element includes a pressure foot for pressing against at least one of the final end coils of said given coil spring when said striking element moves downwardl a ains said ven coils 'n 4. The c m ination d ined in cl iin wherein said entrance means comprises a pair of rigid guide flaps affixed to said frame and converging toward said guide channel to slightly compress said given coil spring.

5. The combination defined in claim 4 wherein said guide flaps have upper edges which project inside the side walls of said guide channel so that the final end coils of said given coil spring slide from said guide flaps onto said advancing plates when said advancing plates receive said given coil spring from said entrance means.

6. The combination defined in claim 1 wherein said advancing plates have the same thickness everywhere.

7. In a stacking device for helical coil springs which have a final coil at each end that terminates in a knot, the stacking device being of the type having a frame with side walls and a floor defining a guide channel to which the coil springs are supplied by a transfer arm in an orientation with the knots on top and within which guide channel the coil springs are advanced forwardly for stacking, the combination with said frame comprismg:

a pair of rigid guide flaps affixed to said frame and converging toward the guide channel for receiving and slightly compressing a given coil spring being supplied to said guide channel on said transfer slide means reciprocally slidable on said frame longitudinally of said guide channel;

a pair of advancing plates carried by said slide means and spaced inwardly of said guide channel side walls .to receive said given coil spring on said transfer arm from said pair of rigid guide flaps, said slide means being operative following reception of said given coil spring on said transfer arm by said pair of advancing plates to move said advancing plates rearwardly causing said given coil spring to slide off said advancing plates and expand for engagement with said guide channel side walls to permit release of said given coil spring by said transfer arm whereupon said slide means is operative to move said advancing plates forwardly so that each of said advancing plates engages the knot oriented at the top of the final coil of said given coil spring at the associated end of said given coil spring to simultaneously partially rotate and advance said given coil spring into stacking relationship with the preceding coil spring; and

alignment means including a normally raised striking element movable in a vertical plane, said alignment means being operable when said given coil spring has been advanced into stacking relationship with the preceding coil spring to cause said striking element to move downwardly against said given coil spring urging said given coil spring downwardly into contact with the floor of said guide channel.

Claims

1. In a stacking device for helical coil springs which have a final coil at each end that terminates in a knot, the stacking device being of the type having a frame with side walls and a floor defining a guide channel to which the coil springs are supplied by a transfer arm in an orientation with the knots on top and within which guide channel the coil springs are advanced forwardly for stacking, the combination with said frame comprising: entrance means affixed to said frame for receiving and slightly compressing a given coil spring being supplied to said guide channel on said transfer arm; slide means reciprocally slidable on said frame longitudinally of said guide channel; and a pair of advancing plates carried by said slide means and spaced inwardly of said guide channel side walls to receive said given coil spring on said transfer arm from said entrance means, said slide means being operative following reception of said given coil spring on said transfer arm by said pair of advancing plates to move said advancing plates rearwardly causing said given coil spring to slide off said advancing plates and expand for engagement with said guide channel side walls to permit release of said given coil spring by said transfer arm whereupon said slide means is operative to move said advancing plates forwardly so that each of said advancing plates engages the knot oriented at the top of the final coil of said given coil spring at the associated end of said given coil spring to simultaneously partially rotate and advance said given coil spring into stacking relationship with the preceding coil spring.

3. The combination defined in claim 2 wherein said striking element includes a pressure foot for pressing against at least one of the final end coils of said given coil spring when said striking element moves downwardly against said given coil spring.

4. The combination defined in claim 1 wherein said entrance means comprises a pair of rigid guide flaps affixed to said frame and converging toward said guide channel to slightly compress said given coil spring.

7. In a stacking device for helical coil springs which have a final coil at each end that terminates in a knot, the stacking device being of the type having a frame with side walls and a floor defining a guide channel to which the coil springs are supplied by a transfer arm in an orientation with the knots on top and within which guide channel the coil springs are advanced forwardly for stacking, the combination with Said frame comprising: a pair of rigid guide flaps affixed to said frame and converging toward the guide channel for receiving and slightly compressing a given coil spring being supplied to said guide channel on said transfer arm; slide means reciprocally slidable on said frame longitudinally of said guide channel; a pair of advancing plates carried by said slide means and spaced inwardly of said guide channel side walls to receive said given coil spring on said transfer arm from said pair of rigid guide flaps, said slide means being operative following reception of said given coil spring on said transfer arm by said pair of advancing plates to move said advancing plates rearwardly causing said given coil spring to slide off said advancing plates and expand for engagement with said guide channel side walls to permit release of said given coil spring by said transfer arm whereupon said slide means is operative to move said advancing plates forwardly so that each of said advancing plates engages the knot oriented at the top of the final coil of said given coil spring at the associated end of said given coil spring to simultaneously partially rotate and advance said given coil spring into stacking relationship with the preceding coil spring; and alignment means including a normally raised striking element movable in a vertical plane, said alignment means being operable when said given coil spring has been advanced into stacking relationship with the preceding coil spring to cause said striking element to move downwardly against said given coil spring urging said given coil spring downwardly into contact with the floor of said guide channel.