WO2007077325A1

WO2007077325A1 - Method and device for making a part comprising a swaged ring using progressive die stamping

Info

Publication number: WO2007077325A1
Application number: PCT/FR2006/002801
Authority: WO
Inventors: Christian Zug
Original assignee: Jtm
Priority date: 2005-12-26
Filing date: 2006-12-20
Publication date: 2007-07-12
Also published as: FR2895292A1; FR2895292B1

Abstract

The invention concerns a method whereby a ring (13) is inserted and swaged using a progressive stamping die (22) in a sequence of cutting and crimping operations (27, 28, 29), and including a step (31) of inserting and pre-crimping the ring and a separate final crimping step (33). The progressive stamping die (22) comprises means (4) for conveying and positioning the rings, guiding means (5) for axially guiding each ring, inserting means (6), sliding axially around the guiding means to introduce the ring in the hole of the part, and co-operating with the pre-crimping means (7) coaxially located facing the inserting means, to flare out the edge (15a) of the ring after it has passed through the hole, and crimping means (9), located downstream, in the moving direction of the sheet metal strip, of the guiding, the inserting and the pre-crimping means, to cause the ring to be completely crimped on the part.

Description

Method and device for manufacturing by progressive stamping of a part comprising a crimped ring.

The present invention relates to an improvement to presses for cutting-stamping metal parts and their implementation for the manufacture of stamped parts, provided in particular to include friction rings or the like, inserted and crimped in holes cut in these parts.

More specifically, it relates to mechanical presses cutting-stamping provided with a progressive tooling, general principle known per se, arranged to achieve a finished or semi-finished part by a succession of cutting and stamping operations performed on a strip of sheet fed into the press and progressively moved between the two parts of the tooling in different positions integrated in the same press tooling. During this movement, these different stations perform the successive operations of cutting and shaping that transform the flat sheet into a piece of three-dimensional shape. Often, these parts, such as for example the rod shown in Figures 1 and 2, must have rings, bearings or other similar elements crimped on the part. In the example shown in the drawings, the rod 1 comprises a split friction ring 13 inserted and crimped into a previously cut hole in the room. Commonly, the hole is punched during the manufacture of the part in the progressive tooling press, and the ring is inserted and crimped on the part during a specific subsequent operation, which therefore requires a recovery of previously cut parts and formed. This additional operation therefore entails unit costs important that it is desired to reduce, especially since the parts are manufactured in large series.

It is already known, from document US Pat. No. 3,588,990, to integrate, in a series of operations of making a part by cutting with a device of the progressive tooling type, steps of insertion and crimping of a ring. then a journal, by self-cutting and insertion force in a sheet, and guided on the ring and then ensure the positioning of the trunnion. Such a force insertion with cutting by the insert itself, can only be used in very particular configurations of the characteristics of the assembled parts for the implementation of such a method, and in particular not for the implementation of rings of reduced thickness.

It has already been proposed to incorporate, in the following cutting and shaping operations by progressive press tooling, a step of insertion and crimping of a fixing insert, nut, stud or the like. The documents EP-A-827804 and US2001 / 0010114 in particular describe such methods and shows tools provided for their implementation.

The system described in EP-A-827804 shows in particular a device adapted for the establishment of a self-sealing nut. In this system, a self-crimping nut is brought into position by a sliding drawer and then taken up in a housing formed by two half-rings clamped together by springs. Then the self-crimping nut is inserted and crimped in the sheet, in the same operation, by a striking performed by means of a punch actuated by the press. Such a method can not be used for setting up and crimping rings as referred to by the invention, that is to say slotted ring rings, of small thickness. Indeed such rings are much more fragile than the self-crimping nuts of the method above and can not be inserted and crimped by striking, without significant risk of being deformed before insertion into the hole of the sheet or at least during insertion, crimping can not be made under such conditions.

The system described in the document US2001 / 0010114 aims at the establishment of a stud set in a sheet. The tooling in place of the stud is complex and its size can make integration difficult in a progressive tool of the conventional type. In addition, this tooling supply would not be compatible with the establishment of rings as referred to in the present invention.

In fact the systems, as mentioned above, combining an implementation of an insert in a stamped part with the progressive stamping cutting operations, are essentially for the insertion and crimping of relatively large pieces, such as the nuts or studs mentioned above. Such parts can indeed be inserted and crimped without the need to ensure high positioning accuracy, and crimping can be done on the fly, under the effect of a significant force exerted by the press directly on the insert in the direction of the axis thereof. Such a procedure is inapplicable for parts whose small thickness and relative fragility resulting can not withstand shocks or forces as important without incommensurable uncontrollable deformation.

The present invention aims to solve the various problems mentioned above and aims in particular to allow the insertion and crimping of thin friction rings in sheet metal parts cut and stamped on a progressive tool press, and this in the normal course of the part manufacturing cycle, and using progressive tooling. The invention thus aims to eliminate the necessary recovery operation according to the prior art, and thus to significantly reduce the manufacturing costs of the finished part equipped with its crimped ring.

With these objectives in view, the subject of the invention is a process for manufacturing a stamped metal part comprising a ring set in a hole in the part, according to which the metal part is cut and stamped in a progressive tooling press. characterized in that the insertion and crimping of the ring are performed by means of the progressive tooling in the following operations of cutting and stamping, and comprise a step of insertion and pre-crimping of the ring and a separate step of final crimping.

The ring can thus be positioned precisely, inserted into the hole and pre-set without undergoing significant efforts that may deteriorate, the final crimping being provided on a separate station.

Preferably, a step of checking the presence of the ring is performed between the insertion and pre-crimping step and the final crimping step.

According to a preferred arrangement, the insertion and pre-crimping step comprises a phase of supply and positioning of the ring to bring the ring into an axial alignment position with a guide finger, and an insertion phase. and pre-crimping by a sliding insertion pin coaxially around the guide pin and arranged to insert the ring into the hole of the part and then pre-crimping by a flaring of the edge of the ring protruding from the workpiece, means of a pre-crimping die having a frustoconical scope, located coaxially and facing the insertion punch.

Note that the deformation of the ring for pre-crimping the piece begins only after the ring is fully inserted into the hole. This results from the fact that the ring is first inserted into the hole of the part, maintained in elevation relative to the pre-crimping die, and only then the part, which is supported by a vertically displaceable part plate, is lowered under the thrust exerted by the insertion punch on the ring until the lower edge of the ring comes into contact with said pre-crimping die and begins to flare thereon. In addition, until the end of pre-crimping, the guide finger remains present in the bore of the ring, which provides an additional guarantee against a possible risk of deformation of the ring under the inevitable axial forces due to the pre -sertissage

The subject of the invention is also a device for manufacturing a stamped metal part comprising a ring set in a hole in the part, the device comprising in particular a progressive cutting-stamping tool, comprising an upper plate and a lower plate, for to make said part from a strip of sheet driven in scrolling between said plates, characterized in that the progressive tooling comprises: means for supplying and positioning the rings, means for guiding the rings to guide each ring in the axial direction of the hole of the workpiece, insertion means, sliding axially around the guide means for introducing the ring into the hole, and cooperating with means of pre- crimping located coaxially and facing the insertion means, to flare the edge of the ring which has passed through the piece,

- Crimping means, located downstream, in the running direction of the sheet metal strip, guiding means, insertion and pre-crimping, to completely crimp the ring on the workpiece.

According to complementary arrangements: the insertion means comprise an insertion punch driven vertically by the upper plate of the tool and in which the guide means of the rings are slidably mounted and subjected to an axial thrust spring. the pre-crimping means comprise a pre-crimping die integral with the lower plate and comprising a frustoconical pre-crimped end.

- Control means are arranged between the guide means, insertion and pre-crimping and the crimping means, and preferably comprise a control matrix arranged on the lower plate to support the pre-set ring in the room and a probe slidably mounted on a guide secured to the upper plate and arranged to actuate a presence switch and correct insertion of the ring.

According to a first embodiment, the feeding and positioning means comprise a loading slide for moving each ring and placing it in axial alignment with the guiding and insertion means, resting on a set of support clamps, the insertion means comprising control cams for spreading the tongs during the descent of the means insertion, to allow the introduction of the ring in the hole of the room.

According to a first variant, the feeding and positioning means comprise a loading slide for moving each ring and placing it in axial alignment with the guiding and insertion means, the drawer carrying a ring support pawl and the ratchet being retractable to allow the introduction of the ring into the hole of the room.

According to a second variant, the feed and positioning means comprise a loading carriage carrying the insertion and guide means and movable horizontally, the guide means being arranged to move each ring and to align it axially with the means pre-crimping during a movement of the carriage controlled by the descent of the upper plate, the rings being supported during this movement by a fixed guide rail and the piece adjacent said rail.

Other characteristics and advantages will appear in the description which will be made, by way of non-limiting example, of a method and a cutting-stamping device according to the invention, for the production of a rod provided with of a friction ring.

Reference is made to the accompanying drawings, in which: FIG. 1 is a perspective view of the link,

FIG. 2 is a view in longitudinal section of said link,

FIG. 3 is an overall view of the press equipped with a progressive cutting-stamping tool comprising the ring insertion and crimping device, FIG. 4 is a view from below of the upper plate of the progressive tooling, FIG. 5 is a top view of the lower plate of the progressive tooling, FIG. 6 shows the sheet metal strip from which the links are realized, and more precisely the portion of this band located at a given moment in the grip of the progressive tooling,

FIG. 7 is a view of the device for feeding and positioning the rings, during the feeding phase,

FIG. 8 is a sectional view along the line A-A of FIG. 7,

FIG. 9 is a sectional view along line BB of FIG. 7, FIGS. 10 to 12 are views corresponding to FIGS. 7 to 9, during the positioning phase, FIGS. 13 and 14 are corresponding views. at the beginning of the insertion phase, FIGS. 15A, 15B, 15C illustrate the various stations of the progressive tooling, respectively of insertion and pre-crimping, of control of presence of the ring, and of final crimping, at at the same time, in the high stroke position of the press and therefore of the upper plate of the progressive tooling, FIGS. 16A, 16B, 16C similarly illustrate the various stations in the intermediate position,

FIGS. 17A, 17B, 17C similarly illustrate the different stations in the low position; FIGS. 18 to 20 illustrate a first embodiment of the means for bringing and positioning the ring, in the three successive positions of FIG. brought, positioning and return, Figures 21 to 23 illustrate the successive positions, during the descent of the upper plate, guide means and pre-crimping this first variant, Figures 24 to 26 illustrate a second embodiment of the supply means, positioning, and pre-crimping of the ring, in the three successive positions of brought, positioning and pre-crimping

The rod 1 shown in FIGS. 1 and 2 comprises a body 11 made of stamped and cut metal sheet, in which two holes 12 are punched, one receiving a split collar ring 13, the collar 14 pressing against one side of the connecting rod 1 and the end 15 of the ring opposite the flange being folded against the other side of the rod to ensure the crimping of the ring. By way of non-limiting example, the diameter of the ring 13 may be from 8 to 30 mm, with a wall thickness of the order of 0.5 mm.

Figure 3 schematically illustrates the assembly of the pressing press 2 stamping used to produce the rod 1, according to the invention. The press 2 comprises in particular a frame 21 which is placed a progressive tooling 22 comprising a lower plate 23 and an upper plate 24, between which the sheet metal strip 3, from which the rods 1 are made, scrolls so as to pass in each of the progressive tooling stations, in a manner known per se. Note the presence of two vibratory bowls 25, or similar devices similar parts distribution, which serve to bring the rings 13 to the progressive tooling 22, by means of two troughs 26 transport, which may be for example rails or flexible plastic tubes, where the rings are displaced by blowing or vibration. The progressive tooling, whose upper plates 24 and lower 25 are respectively shown, in a simplified manner, FIGS. 4 and 5, comprises, in a conventional manner, the tools necessary for cutting and shaping the rod, distributed on posts successive diagrammatically marked on the drawings, namely: pre-cutting stations 27, followed by stamping stations 28, and - complementary cutting and punching stations 29.

This first part of the progressive tooling has only elements of known type, aiming to gradually form in a manner also known, the rods 1 from the sheet metal strip 3, as shown in Figure 6, which shows the said sheet metal strip 3 in the state where it occurs during manufacture, making it possible to gradually see the rods 1, cut and stamped and still attached to the central drive band, from which the rods are permanently separated later , right out of the press.

According to the invention, the progressive tooling 22 comprises a second part located downstream, in the direction of travel of the band 3, of the first part, and intended for the positioning and crimping of the rings 1, and on which the chutes 26 for transporting the rings end, one of the chute 26a feeding the insertion device located on one side of the tool, and the other chute 26b supplying the insertion device located on the other side, as can be seen in particular in Figure 5.

The two sets of tools, used for setting up and crimping the rings on the rods located on both sides of the central drive band, being of identical constitutions, at one end. symmetry almost eventually, we will describe later only one of these sets of tools.

This set comprises three successive positions:

an insertion and pre-crimping station 31, a checkpoint 32,

- a final crimping station 33.

At the level of the insertion station, the tooling

means 4 for feeding and positioning the rings,

means 5 for guiding rings,

insertion means 6,

pre-crimping means 7.

The means 4 for feeding and positioning the rings comprise a slide 41 sliding in a housing 422 of a support block 42 and actuated by a jack 43. The support block 42 also comprises a guide path 421 on which connects the chute 26 and which opens into the housing of the drawer, in front of a chamber 411 formed in the drawer to receive a ring 13, when the slide 41 is in the retracted position as shown in Figure 7. A retaining finger 44 is guided in the support block 42 vertically above the guiding path 421 and movable vertically by a jack 45, so as to fit into the first ring 13a which remains in the guide path 421 when the slide 41 is moved, to retain said ring 13a, as can be seen in FIG 11, and thus prevent this ring is pushed against the slide 41 by the other rings from the dispensing device 25.

The support block also carries a set of support clamps 45 guided in translation horizontally on said block and pushed towards each other by springs 451. The clamps 45 comprise in their opposite parts, 452 forks which have a cutout 453 in a semicircle and whose upper face 454 is located at the bottom wall of the housing 422, which supports the ring moved by the slide 41. The forks 452 are thus arranged to support the ring 13 brought by the slide 41, as shown in Figures 10 and 12, said ring falling into the hole formed by said cutouts 453 of dimensions provided for this purpose, but being retained by its flange 14 resting on said forks 452. Note that the spool stroke, and the positioning of the forks are determined so that the hole formed by the cuts 453, and therefore the ring 13 when it is brought into this hole by the slide, are axially aligned with the guide means 5 and insertion 6 rings, as shown in Figure 15A and as will be explained later.

The guide means 5 for the rings comprise a guide pin 51 having a conical or frustoconical lower end 511 and a diameter substantially equal, with a minimum clearance, to the inside diameter of the rings 13.

The insertion means 6, which are rigidly connected to the upper plate 24 of the progressive tooling, comprise a tubular part constituting an insertion punch 62 whose lower end is of size and shape able to press and push on the flanges 14 of the rings, while having an outer dimension sufficiently small to pass into the chamber 411 of the drawer 41, as seen in Figures 14 and 16A.

The guide pin 51 is slidably mounted vertically coaxially in the insertion punch 62, and pushed downwards by a spring 52 placed in a bore 611 of the body 61 of the insertion means 6, this bore comprising a shoulder forming a stop for a flange 512 upper end of the guide pin.

The insertion means further comprise two vertical cam fingers 63 whose lower end 631 is tapered. The shapes and dimensions of these cam fingers are determined so that they can penetrate holes 455 of the support clamps 45, these holes also having a bevelled portion 456, so that by inserting into said holes 455 by downward movement when lowering the upper plate 24, the cam fingers 63 move the support tongs 45 away from each other, pushing them against the springs 451. The spacing value grippers caused by the cam fingers 63 is provided so that the forks 453, by moving apart, leave between them sufficient space for the passage of the flange 14 of the ring and the insertion punch, as seen in FIGS. 14 and 16A in particular.

The pre-crimping means 7 comprise a pre-crimping die 71, coaxial with the guide finger 51 and the insertion punch 62, and integral with the lower plate 23. The upper end of said die has a cylindrical stud 711, of diameter corresponding to the internal diameter of the ring 1, which is connected to the body of the matrix 71 by a frustoconical portion 712, substantially at 45 ° for example.

Furthermore, the sheet metal strip and the links in progress are supported by a workpiece plate 72, vertically movable and supported by springs 73. A pusher 74 secured to the upper plate 24 is arranged to press on the strip 3 and the door pan 72 when the top plate 24 descends. Thus the rods, which are in the upper stroke of the upper plate, supported at a level slightly higher than that of the upper end of the pre-crimping die 71, can go down so that the rings 13, after being inserted into the hole of the rod by the punch 62, can be inserted on said pin, and be flared on the frustoconical portion, as shown in FIG 17A and as this will be explained later.

At the control station 32, and as seen in FIG. 15B, the control tooling 8 comprises a control matrix 81, integral with the lower plate 23, and whose front end face comprises a bowl 811, adapted to receive the edge 15a of the ring partially flared after the pre-crimping A control probe 82 is mounted, coaxially aligned with the control matrix 81, sliding in a guide 83 secured to the upper plate and pushed down by a spring 84. The probe 82 has a lower end of diameter substantially equal to that of the flange 14 of the ring 13 and carries a probe finger 821, arranged to actuate a switch 85 when the sensor is pushed upwards. At the crimping station 33, as shown in FIG. 15C, the crimping tool 9 comprises a crimping die 91 integral with the lower plate 23, and whose upper end carries a crimping nipple 911 of diameter equal to the inside diameter of the crimping tool 9. the ring 13, and which is connected to the body of the matrix 91 by a crimping shoulder 912. A crimping punch 92 is mounted, coaxially aligned with the die 91 and secured to the upper plate, its lower end being arranged to press flat on the flange 14 of the ring 13 and having a clearance 921 adapted to be inserted and centered on the crimping nipple 911 in the bottom stroke of the upper plate, to finish the crimping of the ring by completely folding the flared edge 15a, the pin 911 preventing the central portion of the ring from deforming. We will now resume the entire sequence of operations performed for the crimping of a ring 13 on the rod 1, according to 1 invention. After a previous ring has been inserted into the hole of a link and pre-set, the upper plate 24 rises, and the slide 41 is returned to the position of FIGS. 7 and 8. The retaining finger 44 is lifted by the jack 441, allowing all the rings located in the trough 26 and the feed path 421 to advance, the ring 13 which was retained by the finger 44 then being housed in the chamber 411 of the drawer 41. The said retaining finger 44 resumes its place to hold the other rings (see Figure 11), and the slide 41 is then actuated by the jack 43, to bring the ring 13 over the forks 452 of the support clamps 45, as shown 10, the ring 13 falling by gravity in the hole formed between the forks but being retained thereon by its flange 14, as shown in Figures 12 and 15A. In this position the ring is already substantially centered on the axis of the hole of the rod 1, brought into position by the conventional conventional mechanisms of advance of the strip 3. The operations, which have just been described, of bringing into position of the ring 13 are performed in the normal course of the press operating cycle, between the moment when the raising of the upper plate, and therefore of the guide pin 51, allows the slide 41 to move back, and the moment when the descent the upper plate is again engage the guide pin in the ring positioned on the forks.

Due to the descent of the upper plate 24, the guide pin 51 engages in the ring 13, the conical end of the finger facilitating the centering of the ring. Simultaneously, the cam fingers 63 enter the holes 455 of the support clamps 45 and the apart, the ring can then descend to the rod 1 while remaining perfectly guided on the guide pin 511, whose pointed end itself itself to be centered in a conical hole 713 pre-crimping pin 711. The continuation of the lowering of the upper plate 24 causes the insertion punch 62 in contact with the flange 14 of the ring, and pushes the ring into the hole of the rod, as shown in Figure 16A. Note that at this time, the link remains supported by the door plate parts 72, the springs 73 being sized to resist without bending the insertion force of the ring.

Continued descent of the upper plate 24 then causes firstly the descent of the door plate parts 72 under the effect of the pusher 74, and simultaneously the insertion punch brings the ring 13, by sliding on the finger of 51, on the pre-press nipple and in contact with the frustoconical portion 712. It will be noted that the insertion punch and the pusher 74 are arranged in such a way that, during the downward movement, the ring remains well pushed into the hole of the rod with its flange 14 applied against the surface of the rod. Thus, when the lower edge 15a of the ring is pushed against the frustoconical portion 712 which will cause its flaring, as shown in FIG 17A, the rest of the ring, well maintained by the guide pin and the insertion punch, do not risk not to deform inadvertently despite the thinness of the ring. At the end of the stroke, the ring is thus pre-set on the link, with its flared bottom edge as shown in FIG. 17A, as it will be found at the next station, that is to say at the control station 32. where the control is illustrated by FIGS. 15B, 16B, 17B. For this control, the descent of the upper plate 24 brings the probe 82 into contact with the flange 14 of the ring 13, as shown in Figure 16B. The further descent of the upper plate 24 brings the rod 1 substantially in contact with the control matrix 81, the flared edge 15a of the ring being engaged in the bowl 811 of the control matrix 81, and resting at the bottom of this bowl as shown in Figure 17B. If the ring is in place, the probe 82 is found pushed back slightly in its guide 83, against the thrust exerted by the spring 84, this movement actuating the switch 85. In case of absence of ring, the probe may go lower, and the switch will not be operated. In the opposite case where the ring is not sufficiently inserted, the probe would then be pushed back, the contactor can also detect this movement greater than normal. It will also be noted that, in order to facilitate the detection despite the very small thickness of the flange 14, it is expected that, when the rod comes into contact with the control matrix, the ring may be slightly raised relative to the link, by example of the order of 1 mm, by the bottom of the bowl 811, so that the difference in positions of the probe between the case of normal ring presence and absence of ring is more sensitive. This slight axial displacement of the ring in the hole of the connecting rod remains possible at this stage because the flare of the edge 15a of the ring does not immobilize it yet completely on the link. The signal provided by the switch 85 may be used to either signal a defective part only or to stop the press in the event of a more serious problem of improper ring insertion.

At the crimping station 33, during a subsequent race of the press, the ring inserted and pre-crimped on the rod is found positioned axially aligned with the crimping die 91. The descent of the crimping punch brings it into contact with the flange 14 of the ring, as can be seen in FIG. 16C ₇ and the continuation of the descent, simultaneously with the lowering of the workpiece plate 72, causes the insertion of the ring on the crimping nipple 911 of the crimping die 91, and finally crimping by completely flattening the edge 15a to form the flanged edge 15 of the ring. It will be noted that during this final crimping, a deformation of the central part of the ring is avoided by the presence of the crimping stud 911, which guarantees the good internal diameter of the ring. In addition, the penetration of this stud into the clearance 921, visible in FIG. 17C, guarantees firstly the centering of the crimping punch 92 with respect to the die 91, and prevents any risk of backflow of the ring on the side of the flange. .

An alternative embodiment of the feed means and insertion and pre-crimping means is shown in FIGS. 18 to 23. The drawer and support clamp system described above is here replaced by a slide 46 which carries a pivoting ratchet 47, retractable in a housing 461 arranged for this purpose in the drawer, as shown in Figure 20, and pushed out of this housing, in an active position visible Figures 18 and 19, by a spring 462. The ratchet 47 to a hook shape 471, shaped to receive and support a ring 13, as can be seen in FIGS. 18 and 21. In the retracted position of the slide 46, illustrated in FIG. 18, the hook 471 is positioned so that the rings, coming from the guide path 421, can be placed in the hollow of the hook, the flange 14 being supported by the hook. The drawer is then moved by the jack 43, as illustrated in FIG. 19, to bring the ring into its position. insertion, aligned axially with the guide pin 55, as visible in FIG. 21.

After the guide pin 55 is inserted into the ring following the descent of the upper plate 24, the pawl 47 is retracted and the drawer is returned to the retracted position (Figure 20). The ring 13 is then centered by the guide pin 55, as can be seen in FIG. 22, and the further descent of the upper plate brings the insertion punch 65 into contact with the flange 14 of the ring, to insert the ring. in the rod and the pre-crimp, as shown in Figure 23, similarly to the example described above.

A second variant of the feed and insertion means is shown in FIGS. 24 to 26. In this variant, the insertion punch 67 is slidably mounted vertically on a loading carriage 48 that is movable horizontally, guided on a support 49 integral with the tray. 23. The guide pin 57 is mounted in the punch 67 in a manner similar to the previous examples.

The movement of the carriage 48 is controlled by the descent of the upper plate 24, for example by means of a cam 481 which enters a vertical hole 482 of the carriage, the inclined end of the cam acting to move the carriage against a return spring 483.

When the top plate 24 is in the up position, as shown in FIG. 24, the carriage 48 is pushed back by the spring 483 into a position where the guide pin 57 is located vertically above the first ring at the exit of the guide path 421. The descent of the upper plate brings it into contact with the insertion punch and pushes it downwards against a spring 671, thereby driving the guide finger which penetrates into the ring 13. The continuation of the descent of the plate 24 causes the cam 481 to move the carriage 48, thereby driving the ring 13 by means of the guide pin 57. Note that, despite the descent of the insertion punch, the guide pin does not descend from the fact that its lower tip is supported during the horizontal movement, first by the path or guide rail 421 and then by the rod itself. Similarly, the ring is supported first by the guide rail 421, then by the connecting rod adjacent the rail. When the guiding finger and the ring have arrived in the position of axial alignment with the pre-crimping die 71, the guide finger can pass into the hole of the link and focus on the said présertissage matrix, as previously described. , and illustrated in FIG. 25. It will be noted incidentally in this figure the presence of the retaining finger 44, which has moved to retain the rings waiting in the path 421.

Continued descent of the upper plate causes the insertion punch 67 to push the ring and pre-crimp it in the hole of the rod 1. During this last part of the descent, the carriage 48 remains stationary because of the fact that is then the vertical portion of the cam 481 which slides vertically in the hole 482 of the carriage, so without causing any horizontal displacement.

The invention is not limited to the embodiments and applications described above as examples. In particular, the supply rings could also be made by rigid vibrating rails or by tube and air blowing. The movements of the drawers, retaining fingers, support clips, could also be achieved by other means technologically equivalent to the cylinders and cams described. The contactor could also be replaced by equivalent probe position detection means.

Claims

1. A method of manufacturing a stamped metal part (1) comprising a ring (13) crimped in a hole of the part, wherein the metal part is cut and stamped in a press (2) with progressive tooling (22), characterized in that the insertion and crimping of the ring (13) is carried out by means of the progressive tooling (22) in the following operations

(27, 28, 29) and comprise a step (31) of insertion and pre-crimping of the ring and a step (33) separate final crimping.

2. Method according to claim 1, characterized in that a step (32) for checking the presence of the ring (13) is performed between the insertion and pre-crimping step and the final crimping step.

3. Method according to claim 1, characterized in that the inserting and prestressing step (31) comprises a supply and positioning phase of the ring (13) to bring the ring in the axial alignment position with a guide finger (51, 55, 57), and an insertion and pre-crimping phase by an insertion punch (62, 65, 67) sliding coaxially around the guide finger and arranged to insert the ring ( 13) in the hole of the piece then make a pre-crimping by a flare of the edge

(15a) of the ring protruding from the workpiece, by means of a pre-crimping die (71) having a frustoconical bearing surface (712) located coaxially and opposite the insertion punch.

4. Device for manufacturing a stamped metal part comprising a ring crimped into a hole in the part, the device comprising in particular a tool progressive cutting (22), comprising an upper plate (24) and a lower plate (23), for producing said piece from a strip of sheet metal (3) driven in scrolling between said plates, characterized in what progressive tooling includes:

means (4) for feeding and positioning the rings,

means (5) for guiding the rings to guide each ring in the axial direction of the hole in the part,

- insertion means (6), sliding axially around the guide means for introducing the ring into the hole, and cooperating with pre-crimping means (7) located coaxially and facing the insertion means, to flare the edge (15a) of the ring having passed through the piece,

- Crimping means (9), located downstream, in the running direction of the sheet metal strip, guiding means, insertion and pre-crimping, to completely crimp the ring on the workpiece.

5. Device according to claim 4, characterized in that the insertion means comprise an insertion punch (62, 65, 67) driven vertically by the upper plate (24) of the tool (22) and in which the means (51, 55, 57) for guiding the rings are slidably mounted and subjected to a spring (52) axial thrust.

6. Device according to claim 4, characterized in that the pre-crimping means comprise a pre-crimping die (71) integral with the lower plate (23) and having a truncated cone pre-end (712).

7. Device according to claim 4, characterized in that control means (8) are arranged between, on the one hand, the guide means, insertion and présertissage and, secondly, the crimping means, and comprise a control matrix (81) arranged on the lower plate (23) to support the ring ( 13) pre-set in the piece and a feeler (82) slidably mounted on a guide (83) integral with the upper plate (24) and arranged to actuate a contactor (85) for the presence and correct insertion of the ring.

8. Device according to claim 4, characterized in that the supplying and positioning means comprise a loading slide (41) for moving each ring and in axial alignment with the guide means (51) and insertion (62), the ring resting on a set of support clamps (45), the insertion means having control cams (63) for spreading the clamps during the descent of the insertion means, to allow the introduction of the ring in the hole of the piece.

9. Device according to claim 4, characterized in that the feeding and positioning means comprise a loading slide (46) for moving each ring and in axial alignment with the guide means (55) and insertion (65), the drawer carrying a ratchet (47) ring support and the pawl being retractable to allow the introduction of the ring in the hole of the room.

10. Device according to claim 4, characterized in that the feeding and positioning means comprise a loading carriage (48) which carries the insertion means (67) and guide (57) and which is movable horizontally, the guide means (57) being arranged to move each ring (13) and bring it in axial alignment with the pre-crimping means (71) during a movement of the control carriage by the descent of the upper plate (24), the rings being supported during this movement by a fixed guide rail (421) and by the part (1) adjacent said rail.