SK4599A3 - Device for setting rivets, buttons or the like - Google Patents

Abstract

A device for setting rivets, buttons or the like has an upper tool (21) and a lower tool (5). The upper tool (21) can preferably be actuated by a tappet and one of the tools carries out an evading movement during riveting. In order to provide a device of this type characterised by an improved manoeuvrability, a correct riveting and a highly reliable operation, without altering the proven basic design, the extent of the evading movement is used to monitor the riveting operation.

Description

Device for attaching rivets, buttons or the like

Technical field

The invention relates to a device for attaching rivets, buttons or the like, comprising an upper tool and a lower tool, the upper tool preferably being operated by a slide and one of the tools performing a backward movement during the riveting process.

BACKGROUND OF THE INVENTION

A device of this kind is known, for example, from DE 44 31 948 A1. The contents of this patent application are fully incorporated in the contents of the present application, also in order to incorporate the features of this application into the claims of the present application. In this patent application a device is described in which the upper end of the slide which acts on the upper tool is pressed by a spring to the peripheral surface of the cam disc, which is axially located on the drive shaft of the engine. The rivets, buttons or the like to be mounted each consist of an upper part and a lower part. These upper and lower parts are kept in separate containers and are fed from these containers to the charging slider area by means of supply rails. The charging slider is displaceable in a horizontal direction and is equipped with an upper sliding bar and a lower sliding bar. The upper insertion strip always moves one upper part of the object to be inserted into the holding pliers associated with the upper tool, while the lower insertion bar aligns the lower parts of the insertion objects in the region of the lower tool with the upper part. The lower tool is pivotably mounted on the mounting plate such that the lower tool is seated on the underside of the fabric to lower the upper part with the lower part on the fabric by means of the lower part of the object to be placed in the lower tool. The lower part of the fitting is provided with serrations which, by pressing against the underside of the fabric, penetrate through the fabric. The lower tool can, depending on the thickness of the fabric, make a greater or lesser backward movement against the action of the compression spring during the riveting process, which is manifested by pivoting around the bearing pin of the lower tool.

SUMMARY OF THE INVENTION It is an object of the present invention to improve the construction of the described apparatus, while maintaining the proven basic principles, in order to improve the ability to control correct riveting and to increase the operational reliability of the apparatus.

SUMMARY OF THE INVENTION

The problem is solved and the drawbacks of known devices of this kind are largely eliminated by a device for applying threads, buttons or the like, which consists of an upper tool and a lower tool, the upper tool preferably being operated by a slide. The invention is based on the fact that the magnitude of the backward movement is used to follow the riveting process. Thanks to this embodiment, a device for attaching rivets, buttons or the like is achieved with an extremely simple construction and high reliability. The quality of the riveting depends, inter alia, on the depth of insertion of the teeth of the lower part of the fitting under the circumferential flange of the upper part of the fitting, which may be designed as a spherical or spring element. The desired dimensions, the so-called "pinch setting", which is the distance between the upper and lower sides of the thread, should not be exceeded. When threading the upper part with the lower part of the object to be inserted, i.e. a thread, a knob or the like, on a single or multilayer fabric, the tool recesses more or less against the force of the alignment spring. The path of the backward movement can be considered as a measure of the crimping strength.

An embodiment of the device in which the downward movement of the lower tool is used for monitoring is advantageous in that the sensor tracks the path of movement of the lower tool. By checking the recess rate, a check is obtained which, for example, gives an indicator to the operator f whether the depth of immersion of the teeth of the lower part into the peripheral flange of the upper part of the fitting object is sufficient.

In this case, a solution can be used in that the lower tool activates a contact switch which issues a fault message when the preset travel is exceeded. The embodiment in which the device is stopped in this case is preferred. In this way, the operator is instructed to inspect and / or repeat the riveting. The path of movement of the lower tool is preferably monitored by means of a sensor. This measuring sensor can be located, for example, on the alignment spring of the lower tool. The measuring sensor is z

then, in cooperation with the evaluation circuit, is able to reliably indicate whether the depth of insertion of the teeth of the lower part into the peripheral flange of the upper part of the fitting object is sufficient. This also makes it possible to make judgments about pinch setting, which corresponds to the distance between the upper and lower sides of the thread or the like after the riveting has taken place. Alternatively, a lower tool may activate a switch after exceeding a predetermined path of the recess movement. This switch can be designed as a contact switch or proximity sensor. If the preset maximum path is maintained, the switch located in the path of the lower tool is not activated. The riveting is correct in terms of the allowable distance between the lower and upper sides of the formed thread. However, if objects such as rivets, buttons or the like are applied to a multilayer fabric whose thickness causes the predetermined path of the downward movement of the lower tool to be exceeded, the lower tool is activated by a switch, for example a contact switch arranged in the path of the lower tool. As a result of the activation of this switch, the plug-in device is preferably stopped. The reliability of the measuring apparatus largely depends on the calibration after the tool or punch has been changed, the change of the fitting with a different tooth length of its lower part or the change of the circumferential flange pressure on the upper part of the fitting. It is therefore necessary, for example, to make calibration as simple as possible by means of optical indication and digital adjusting elements. Thus, for example, a scale or the like can be provided on the device by means of which a switch can be set according to the desired mutual distance between the lower and upper sides of the thread to be formed, which monitors the movement of the lower tool.

The invention also relates to an apparatus as described above, the apparatus comprising supply rails for conveying parts of threads or buttons. In order to achieve a reliable course of the riveting process, a solution is used here, characterized in that at least one supply rail is provided with a sensing device for monitoring the movement of the thread part or the knob. This sensing device senses the movement of the slide-on objects, the actual sensing can be ensured, for example, by a switch built into the supply rail or the like. However, an embodiment is preferred in which each supply rail for the upper and lower parts of the objects to be fitted is provided with a photocell. During the deployment cycle, the moving objects generate voltage pulses as they pass through the photocell area, which can be used so that an error message is sent in the absence of a pulse. Said fault may be caused either by blocking of the part in the supply rail or as a result of the depletion of the rivet supply in the container and / or in the supply rail. By means of this sensing device, not only the presence of the parts of the objects to be placed in the supply rails is monitored, but also the movement of these parts in the supply rails. In particular, the latter makes it possible to draw conclusions as to whether, in the previous deployment cycle, part of the object to be deployed has been removed from the track in question. If this is not the case, the following parts cannot be inserted. A tracking pulse is omitted, which is preferably used to stop the device.

The invention also relates to an apparatus in which the thread or knob part is guided by a lead rail into the movement path of the charging slider. The sensing device is located in the supply rail from the charging slider preferably at a distance corresponding to a plurality of threads or buttons. Due to this embodiment, the idling of the respective supply rail is avoided. If a light barrier is used as the sensing device, the light beam is preferably oriented transversely to the direction of movement of the parts of the objects to be mounted. For this purpose, a suitable light beam passage is provided at a suitable location of the preferably cured supply rail. Furthermore, the device according to the invention can advantageously be designed such that the separate supply rails from the respective containers, where the different upper parts of the objects to be placed, for example the spherical or spring elements already mentioned, are located, are parallel to each other. However, since only one or the other upper part of the object to be fed can be processed in one setting cycle, therefore, only the photocell associated with the top part being fed is activated.

in

A further advantageous embodiment of the device according to the invention consists in monitoring the reaching of the end position of the charging slider (16) in each riveting process.

An embodiment in which the forward end position of the charging slider is monitored is preferred. In this way, the path between the supply rail and the riveting area, i.e. the upper and lower tooling areas, is also monitored. For example, if during the movement of the part of the item to be fed from the supply rail to the riveting region by the charging slider, the part is jammed, the charging slider will not reach its front end position. The achievement of this end position is monitored, for example, by a sensor or switch which generates a signal in the event of a fault, preferably for disconnecting the entire device. Due to this embodiment, the pressure of the slide on the upper tool is prevented in the absence of a part of the object to be placed in the riveting region. Such blank riveting could, for example, result in damage to the fabric.

The invention also relates to a device of the type described above in which the riveting is carried out by means of a slide and the movement of the slide is monitored.

It is particularly advantageous if the movement monitoring of the slide is performed by monitoring the movement of the cam disc which controls the movement of the slide.

In practice, this can be accomplished by placing a control switch on the cam disk or detecting the course of the cam track. The monitoring of the slide movement is particularly advantageous in connection with the tracking of the supply rails, since the removal of the parts of the articles to be fed from the guide rails and thus the displacement of the subsequent parts only takes place at a certain, known interval of the deployment cycle. If the sensor or the like in the slide sensor detects an area of the cam track that is predefined for the feed rails, then the evaluation unit also expects a signal from the feed rail readers. Failure to receive the signals from the supply rail sensing devices at this interval will result in the entire system being stopped. As soon as the predefined area of the cam disc leaves the sensor to monitor the movement of the slide, the sensing devices on the supply rails are deactivated. The time dependence between the signal from the supply rails and the control signal from the cam disc is given by the position of the photocell relative to the parts of the mounted objects in the supply rail. A minimum angular distance of 30 ° is used.

Thus, the signal from the sensing device on the feed rails is monitored depending on the slide movement cycle. The control and monitoring devices described above may be used individually or in combination in the described device.

BRIEF DESCRIPTION OF THE DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS The invention is illustrated by the following non-limiting examples, which are described in the accompanying drawings, in which:

FIG. 1 is a side, partially broken-away view of a device for applying rivets, buttons or the like according to the invention, with the slide in the upper dead position;

FIG. 2 is a detailed view of the device of FIG. 1 in the region of the lower tool and the upper tool, with the slide also in the upper dead position;

FIG. 3 is a front view of the device of FIG. 1, there are shown cartridges for receiving parts of the articles to be mounted;

FIG. 4 is a view corresponding to FIG. 1, but with the tools for the riveting position;

FIG. 5 is a detailed view corresponding to FIG. 2, but showing the position of FIG. 4;

FIG. 6 is a greatly enlarged detail of a thread mounted on the fabric;

FIG. 7 is a further detailed view enlarged from FIG. 5, which shows correct riveting, wherein the boom that actuates the lower tool has released the control switch;

FIG. 8 is a detailed view corresponding to FIG. 7, but in the case where the riveting is not correct due to the excessively thick fabric, the lower tool boom is resting on the control switch;

FIG. 9 is an enlarged sectional view showing a perspective sectional view of an area of supply rails extending from the cartridges to the apparatus;

FIG. 10 is a view corresponding to FIG. 2, but showing a second embodiment of the tracking of the lower instrument;

FIG. 11 is a view corresponding to FIG. 5, but for the embodiment of FIG. 10;

and

FIG. 12 is a view corresponding to FIG. 11, but with incorrect knitting due to too much fabric thickness.

DETAILED DESCRIPTION OF THE INVENTION

The device or machine for putting rivets, buttons or the like according to the invention consists of a vertically oriented stand 2, which is supported by a base plate 1. On the stand 2 is mounted a U-shaped mounting plate 3 rotated 90 ° counterclockwise . The lower arm of this mounting plate 3 forms a boom 4.

At the free end of the boom 4 is located a lower tool 5, which in cross-section comprises a circular anvil 6 into which the lower end 7 of the object to be inserted is inserted.

The lower parts 7 of the push-on objects are previously housed in a magazine 8, which is located sideways from the mounting plate 3 and from which the supply rail 9 runs obliquely downwards towards the boom 4. The lower parts 7 of the push-on objects are formed by retaining elements. they can be connected to two different upper parts of the objects to be mounted. In the drawings, the upper part 10 of the object to be placed is shown. It serves as a functional part in the form of a spherical element and can be attached to the fabric 11 together with the bottom part 7. The two different shaped upper parts 10 of the object to be inserted, i.e. the spherical part and the spring part, are fed from the containers 12 and 13 arranged opposite The charging slider 16 is displaceable in a horizontal direction and is provided with an upper sliding bar 17 and a lower sliding bar 18. The upper sliding bar 17 moves the upper part 10 of the object to be inserted into the container. holding pliers 19, while the lower insertion strip 18 moves the lower part 7 of the fitting object into alignment with the anvil 6 of the lower tool 5. One or the other upper parts 10 of the fitting object can be fed from the magazine 12 or the magazine 13 into the region of movement. supply k The feeds 14 or 15 are controlled by the control solenoids (not shown).

The holding pliers 19 are in alignment with the lower tool 5 in the starting position of the device and are supported by a sliding stone which is guided at the lower end of the slide 20, which is positioned opposite the lower tool 5.

in

The slide 20 carries at its lower end a top tool 21 which in the upper dead position of the slide 20 of FIG. 1 to 3 ends above the bed for the upper part 10 of the object to be placed, which is located in the region of the holding tongs 19.

The slide 20 is provided at its upper end with a roller 22. This roller 22 is pressed by a compression spring 23 to the circumferential normal path of the cam disc 24, which is mounted on the drive shaft 25 of the electromotive drive 26. Thus, the slide 20 is rotated. move down and up again to the upper dead position. A boom 27 is also mounted on the slide 20, which carries the control roller 28. The arm 29 of the lever 31 protrudes against the underside of the control roller 28 and is pivotably mounted on a pin 30 on the mounting plate 3. the lever arm 32 of the lever 31 whose end in the position of FIG. 1 to 3 extends vertically and is provided at this point with a slider 33 into which the sliding block 34 extends. This sliding block is connected to a charging slider 16 which is in the form of a slide and is movable in the slide guide 35 on the stand side 1 .

At the lower end of the lever arm 32, a control path 36 is formed on which a sensor pulley 37 rests, which is located at the free end of the control lever 38. This control lever 38 is mounted on a pin 39 on the mounting plate 3. With a transverse arm 40 of the control lever 38 a tension spring 41 is engaged which presses the control lever 38 against the lever 31. which is consequently pressed by its arm 29 against the control roller 28 of the slide 20.

In contrast to the sensing pulley 37, a cam track 42 is formed on the control lever 38 near the pin 39, which cooperates with a pivot pin 43 that is secured against rotation and is guided in the laterally extending transverse arm 44 of the transfer lever 45. the spring 46 and in the thread of the adjustable counterparts 47 abut against the lower end of the transmission lever 45, which is formed essentially as an angle. The transmission lever 45 extends at the top of its knuckle on a transverse pin 48 on the boom 4. The free end of the transmission lever 45 extends below the lower tool 5. The transmission lever 45 extends angularly into the annular groove 50 at the lower end of the lower tool 5. 6. The return spring 51, which is mounted near the counter 47, acts on the transmission lever 45 so that its sensing pin 43 abuts the control lever 38, as shown in FIG. 1 to 3 in the region upstream of the cam track 42.

A projection lamp 52 serves to precisely fit the parts 7, 10 of the object to be placed onto the fabric 11. This is mounted on a stand 2 and, for example, forms a crosshair on the upper side of the fabric.

According to FIG. 1 to 3, the slide 20 assumes an upper dead position in relation to the respective rotation of the cam disc 24. The upper insertion piece 10 has been transferred to the retaining tongs 19 by the upper insertion strip 17, while the lower insertion strip 18 has moved the lower insertion part 7 into the lower tool 5.

By engaging the foot switch 53, which is located on the base plate I, the drive is switched on, which is associated with the rotation of the cam disc 24 in the direction of the arrow according to FIG. 3, as a result of which the slide 20 moves downwards. As a result, the holding pliers 19 also move downwards and stop at a certain distance from the lower tool 5.

Due to the downward movement of the slide 20, the control roller 28 engages the arm 29 of the lever 11 and deflects the lever H counterclockwise, which is associated with driving the charging slider 16 with its sliding bars 17 and 18. The lever arm 32 of the lever 31 acts during of this process to the sensing pulley 37 of the actuating lever 38 and deflects the actuating lever 38 in a clockwise direction. In this case, the pick-up pin 43 engages the cam track 42, which causes the transmission lever 45 to swivel by means of the transmission compression spring 46 so that the lower tool 5 moves approximately simultaneously with the holding pliers 19 and the slide 20 stopped. the downward slide of the slide 20 and the holding tongs 19 causes the holding tongs 19 to rest on the upper side of the fabric H. On the other hand, the slide 20 moves further downward in order to imitate the lower part 7 with the upper part 10 of the object to be placed. The teeth of the lower part 7 of the fitting object pierce the fabric 11 and slide under the peripheral flange of the upper part 10 of the fitting object.

The lower tool 5 can perform a sagging movement during this riveting process, the magnitude of the sagging movement being dependent on the thickness of the fabric U in the region of the riveting. This deflection movement is made possible by the non-rigid displacement of the transfer lever 45. The pressure equalization is thereby provided by the transfer compression spring 46, which is compressed to a degree corresponding to the deflection movement.

Said deflection movement is used to control the riveting process. For this purpose, in the first embodiment shown in FIG. 1 to 3, contact switch 54 used:

The quality of the riveting depends in particular on the depth of insertion of the teeth of the lower part 7 of the fitting object under the peripheral flange of the upper part 10 of the fitting object, which is designed as a spherical or spring element. This insertion depth is directly dependent on the thickness of the fabric 11 and the length of the teeth on the lower part 7 of the object to be placed. During riveting, a certain amount, which is given by the distance and between the upper and lower sides of the thread 55 after the riveting, must not be exceeded - see FIG. 6. When the lower part 7 and the upper part 10 of the fitting object in the monolayer or multilayer fabric 11 are riveted, the lower tool 5 and the transmission lever 45 associated therewith recede. The degree of this recession can be considered as a measure of the crimping strength.

Said contact switch 54 is displaceably positioned on the mounting plate 3. This makes it possible for this contact switch 54 to be set according to the maximum distance between the upper and lower sides of the thread 55, for example a scale or the like can be provided on the mounting plate 3 for this purpose.

In FIG. Figures 7 and 8 show schematically the interior of two fabrics 11 of different thicknesses. According to FIG. 7, the yarn 55 is mounted on the fabric 11, the thickness of which is such that a predetermined distance between the upper and lower sides of the yarn 55 is selected, which is selected depending on the length of the teeth on the lower part 7 of the fitting object. In this case, the lower tool 5 and the transmission lever 45 do not recede or recede only slightly, so that the control contact switch 54 used is not activated by the transmission lever 45. There is no signal.

According to FIG. 8, on the other hand, a fabric 11 is selected, the thickness of which, using the same bottom part 7 of the object to be set as in FIG. 7 causes the specified distance to be exceeded. The lower tool 5 and the transmission lever 45 recede to the extent that the contact switch 54 is actuated. This actuation generates a signal that can be used, for example, by an evaluation circuit to provide the operator with an optical knockout signal. It is preferred here that the signal causes the device to stop in order to allow checking and eventual repetition of the already performed riveting.

Alternatively to the contact switch 54, measuring sensors, proximity sensors or the like may also be used. In this way, the possibility of obtaining a maximum of simple calibration is possible by means of optical indication and digital input elements. This is particularly important because the reliability of the measuring apparatus depends largely on the calibration after the punch replacement, the change of the set-up objects with different tooth lengths or the pressure of the peripheral flange of the upper part.

In the riveting position, the charging slider 16 is also moved back so far that the sliding strips 17 and 18 are located in front of the fed parts 7 and 10 to be inserted. In this position, the workpiece parts 7, 10 are automatically moved in the supply rails 9, 14 and 15. In each case, the respective workpiece part 10, 7 is positioned in front of the respective sliding rail 17, 18. This displacement of the parts to be inserted 7, 10 is blocked during the remainder of the cycle, since the slide bars 17.

18 or the charging slider 16 are at this time in front of the orifices of the supply rails 9, 14, 15 and close these orifices.

According to the invention, the movement of the displaceable object parts 7, 10 in the supply rails 9, 14, 15 is monitored by a sensing device 56 formed by a light barrier 57, each supply rail 9, 14 and 15 having its own sensing device 56.

These sensing devices 56 sense the movement of the displaceable parts 7, 10 of the objects to be inserted as soon as the deployment process is started. Each deployment cycle generates a pulse in the sensing device 56 as the parts 7, 10 are displaced. This fact can be used to generate a fault message in the absence of a pulse. Such a failure can be caused either by blocking of the parts 7, 10 or also when the supply of parts 7, 10 in the supply rail 9, 14.15 or in the container 8, 12 is exhausted. but also the desired movement as the parts 7, 10 are moved in the retracted position of the charging slider 16.

The light barriers 57, which form the sensor device 56, act approximately transversely to the direction of movement of the parts 7, 10 or, alternatively, to the supply rails 9, 14, 15, which are provided in the supply rails 9, 14, 15. through the through holes 58.

As already mentioned, one of the reservoirs 12, 13 for the upper parts 10 of the objects to be inserted and thus also the respective supply rail 14 or 15 is activated by means of the control electromagnets, thereby also activating the sensor device 56 of the currently active supply rail 14 or 15. so that fault messages from the deactivated supply rail area 15 or 14 are thus avoided.

This control of the supply of the parts 7,10 of the objects to be operated further depends on the movement of the slide 20. Thus, the monitoring used is derived from the movement of the cam disc 24 by which the slide 20 is actuated. a switch 59. so that the signal from the sensing device 56 on the supply rail 9, 14, 15 is brought into temporal or angular dependence on the deployment cycle. The timing control switch 59 sends a signal to the evaluation unit, for example, if the retracted position of the charging slider 16 is detected due to the position of the cam disc 24. At this point, signals from activated sensor devices 56 must also be sent to the evaluation unit. 10 deployed objects. The evaluation unit checks the incoming signals and, in the event of an error message, preferably causes the entire deployment device to stop.

The sensing devices 56 are positioned in the region of the supply rails 9, 14, 15 so as to ensure that there are in each case a plurality of load-bearing parts 7, 10 between the sensing devices 56 and the charging slider 16. Thus it is ensured that the supply rails 9, 14, 15 also do not run completely idle. In the region between the sensing devices 56 and the charging slider 16, there is thus always a reserve of parts 7, 10 of the objects to be mounted.

Furthermore, the supply of the lower parts 7 and the upper parts 10 of the objects to be fed in the region of the lower tool 5 and the upper tool 21 is also monitored. For this purpose, for example, a sensor 60 is mounted on the mounting plate 3 which detects the front end position of the charging slider 16. For example, if the part 7, 10 of the object to be pushed up during the forward movement of the charging slider 16, for example, this leads to a stop of the charging slider 16 and the lever arm 32. This lever arm 32 thus does not reach the sensor area 60. in the event of a fault, it sends a signal. This signal is preferably used to stop the deployment device.

The above-described scanning and control devices can be used in the device according to the invention both individually and in combination.

In addition, depending on the course of the cycle, it is also possible to monitor the signals from the mutual distance between the lower and upper sides of the thread 55 and the signals of the position of the charging slider 16 derived from the position of the cam disc 24.

In FIG. 10 to 12, an alternative embodiment of tracking the distance between the lower and upper sides of the yarn 55 is schematically illustrated in another embodiment. To move the lower tool 5 to the riveting position by the cam disc 24, the linear displacement of the ejector 6L is utilized. A transfer compression spring 62, which is supported at the end opposite to the ejection element 61, rests on a plate 64 on the side of the transfer lever 63. Coaxially with this plate 64, a signal thumb 65 is formed on this plate 64 which passes through the compression spring 62 and the ejector. The free end of this signal finger 65 extends into the sensing area of the sensor 66, which is located on the stand 2.

In FIG. 11 shows a riveting position in which the predetermined distance between the lower and upper sides of the thread 55 is maintained due to the permissible fabric thickness 11. The signaling finger 65, which is directly connected to the plate 64 and the transfer lever 63, has left the sensor area 66 As a result, no signal is sent.

In FIG. 12, the thread 55 is to be mounted on a fabric 11 whose thickness causes a predetermined spacing between the lower and upper sides of the thread 55 to be exceeded. The lower tool 5 and accordingly the transfer lever 63 during the riveting recedes due to too much fabric thickness H. The compression spring 62 is compressed between the ejector element 61 which has not retreated and the plate 64 on the side of the transmission lever 63. The signal thumb 65, which is formed on the plate 64, on the other hand, moves toward the sensing area of the sensor 66, which in this situation sends a signal to turn off the device or at least to the indicator for informing the operator.

The features of the invention described in the foregoing description and claims, and illustrated in the drawings, may be relevant to the practice of the invention both individually and in any combination. All the features described are important to the invention. The scope of the invention is also determined by the content of the respective priority application, the full content of which is hereby claimed.

Claims (12)

PATENT CLAIMS A device for attaching rivets, buttons or the like, comprising an upper tool (21) and a lower tool (5), wherein the upper tool (21) is preferably operated by a slide (20) and one of the tools (21, 5) during the riveting process, a backward movement, characterized in that the amount of backward movement is used to follow the riveting process. Device according to claim 1, or in particular according to this claim, characterized in that the follow-up movement of the lower tool (5) is used for tracking. Device according to one or more of the preceding claims, or in particular according to these claims, characterized in that the sensor tracks the path of movement of the lower tool (5). Device according to one or more of the preceding claims, or in particular according to these claims, characterized in that the lower tool (5) activates a contact switch (54) when the predetermined path is exceeded. Apparatus according to one or more of the preceding claims, or in particular according to these claims, wherein the apparatus comprises supply rails (9, 14, 15) which are conveyed by thread or button parts (7, 10), characterized in that at least one supply rail. (9, 14, 15) is provided with a sensing device (56) for monitoring the movement of the thread or knob part (7, 10). Apparatus according to one or more of the preceding claims, or in particular according to these claims, wherein the thread (7, 10) part or button is guided by the supply rail (9, 14, 15) into the movement path of the charging slider (16), the sensing device (56) is disposed in the feed rail (9, 14, 15) from the charging slider (16) at a distance corresponding to a plurality of threads or buttons (7, 10). Device according to one or more of the preceding claims, or in particular according to these claims, characterized in that the end position of the charging slider (16) is monitored at each riveting process. Device according to one or more of the preceding claims, or in particular according to these claims, characterized in that the forward end position of the charging slider (16) is monitored. Apparatus according to one or more of the preceding claims, or in particular according to these claims, wherein the riveting is carried out by means of a slide (20), characterized in that the movement of the slide (20) is monitored. Apparatus according to one or more of the preceding claims, or in particular according to these claims, characterized in that the movement monitoring of the slide (20) is performed by monitoring the movement of the cam disc (24) which controls the movement of the slide. Apparatus according to one or more of the preceding claims, or in particular according to these claims, characterized in that a control switch (59) is provided on the cam disc (24). Apparatus according to one or more of the preceding claims, or in particular according to these claims, characterized in that the signal from the sensing device (56) on the supply rails (9, 14, 15) is monitored depending on the slide movement cycle (20).