EP0120309A2 - Pneumatic-hydraulic setting tool for blind rivet nuts - Google Patents

Abstract

A tool for setting blind rivet nuts has a housing having a head defining a head axis, a pulling rod extending along and rotatable about the head axis, projecting axially forwardly from the head, and threadable into a blind rivet nut, and a hydropneumatic actuator including a rear air chamber and a source of air under pressure for axially displacing the rod along the axis between an extended position projecting axially relatively far from the head and a withdrawn position axially therebehind. A pneumatic motor connected to the pulling rod for rotating same in one sense to screw it into a rivet nut and for rotating the rod in the opposite sense direction to screw it out of the nut. A manually operable valve is connected to the motor unit for rotating the rod in the one sense and an automatic valve independent of the manual valve unit is connected to the rod and between the rear chamber and the motor for feeding air from the air chamber to the motor unit and thereby automatically rotating the rod in the opposite sense on displacement of the rod by the hydropneumatic actuating unit from the extended to the withdrawn position.

Description

The invention relates to a pneumatic-hydraulic setting device for blind rivet nuts consisting of a pneumatic-hydraulic transmission system and a pneumatically and hydraulically connected device head, in which a pulling device that carries a mandrel protruding from the mouthpiece of the device head for processing (setting) one the threaded rivet screwed-on blind rivet nut can be moved axially against a restoring force, the part of the pulling device carrying the threaded mandrel for driving up and down the blind rivet nut being drivable by a compressed air motor accommodated in the device head, the compressed air before the actual riveting process for drilling the blind rivet nut and after the riveting process Compressed air can be supplied to drill off the blind rivet nut, and a valve arrangement.

Blind rivet nuts are fastening elements that enable a screw connection for parts that are only accessible from one side, but also allow a rivet connection. In the unprocessed state, a blind rivet nut consists of a hollow cylindrical rivet shaft, at one end of which it is radial stretching setting head is formed and the opposite end of which has an internal thread, as described, for example, in German utility model 72 08 625. To process such a blind rivet nut, the blank is screwed with the setting head first onto a threaded mandrel firmly connected to the pulling device of a blind riveting device, the internal thread of the blind rivet nut and the external thread of the threaded mandrel of course having to correspond. The rivet shank is then inserted with the threaded section first into the drill hole of the material to be joined until the setting head rests on the latter. By actuating the blind riveting tool, the threaded mandrel is moved backwards by the pulling device, the rivet shaft being compressed between its threaded section and the back of the material to be joined, with the formation of a radially extending, annular swelling bead (swaging, "closing head"). Then the threaded mandrel of the pulling device of the blind riveting tool must be unscrewed from the blind rivet nut. The finished rivet connection then offers the possibility of a screw connection. Blind rivet nuts are particularly suitable for creating the possibility of a detachable screw connection on thin materials into which a thread cannot be cut due to their small thickness, if necessary even without a special rivet connection, by using the blind rivet nut only in one of the parts to be detachably connected.

For processing, i.e. Various devices are already known for setting such blind rivet nuts. There are different versions of purely mechanical devices for different work areas, determined by the size of the blind rivet nuts, which can be operated in the manner of lever pliers; these devices contain a manually operated drilling device connected to the pulling device for screwing and loosening the threaded mandrel carried by the pulling device into or out of the blind rivet nut.

In the setting tool for blind rivet nuts described in the already mentioned German utility model 72 08 625, the thread is cut open directly on the section of a draw bolt protruding from the mouthpiece of the device, which is rotatable and axially displaceable within a bore of the mouthpiece and by means of its opposite the threaded section, radially widened head end can rest in the starting position on a step of the bore. A hexagonal recess is also provided in the head end, into which an expedient drive device for rotating the draw bolt can engage. According to the proposal of the utility model, the draw bolt can either be used with a Hexagon wrench can be turned by hand or with the aid of an air motor, which is housed in a housing that can be connected to the mouthpiece and drives a hexagon shaft that engages with the draw bolt. Compressed air is supplied to the compressed air motor by actuating a switch on and off via a compressed air line, which can be initiated by means of a control button for left and right rotation of the motor, which then drives the draw bolt via the hexagonal shaft. In this way, the threaded portion of the draw bolt is first screwed into the blind rivet nut with its entire length protruding from the mouthpiece, so that during the subsequent riveting process the mouthpiece rests against the setting head of the blind rivet nut with a conical projection surrounding the threaded draw bolt and can widen and further enlarge it firm engagement with the setting head prevents rotation of the blind rivet nut; because according to the proposal of the utility model, the subsequent riveting process should also be carried out by the drive of the compressed air motor, for which purpose the rotary movement of the compressed air motor must be converted into a pulling movement of the pull bolt, as a result of which the blind rivet nut on the back of the material to be joined is compressed to form a rivet or closing head becomes. After the riveting process is completed, reversing the direction of rotation of the compressed air motor turns the threaded draw bolt out of the blind rivet nut loosened. While screwing the blind rivet nut up and down on and off the threaded draw bolt with the aid of a compressed air motor does not cause any difficulties, in order to be able to apply the tensile force required for the actual riveting process, the compressed air motor must correspond to the inflowing compressed air at a given pressure offer a large contact surface so that the required torque can be applied and the compressed air motor does not stop during the riveting process or is stalled. On the other hand, the device is not designed for the processing of blind rivet nuts of all materials in terms of engine power; when using blind rivet nuts of softer materials than steel, such as aluminum alloy, there is a risk that the thread of the blind rivet nuts will tear during the riveting process. The coupling provided in the drive system must be adjusted according to the blind rivet nuts to be processed. The performance of the device can be impaired by compressed air fluctuations. At the end of the utility model specification, the possibility is also indicated of being able to effect the pulling movement of the threaded pull bolt to the rear without further rotation thereof, for example using a cam provided with a lever or with the aid of a media-operated piston-cylinder unit. However, no more precise instructions are given; in particular, remains open as pneumatically actuated in the case of _{'Kolban-Zylinderein-} unit is to be diverted from the air motor to the piston-cylinder unit after the twisting process. However, it is clear that in order to be able to apply the required tensile force, in the one case a relatively long lever and in the other case a piston-cylinder unit is required, which offers the inflowing compressed air the correspondingly large area of action, which requires large external dimensions. Since the pull thread is cut directly onto the pull bolt, the device could only be converted to different sizes of blind rivet nuts by replacing the entire threaded pull bolt. It should also be noted that blind rivet nuts with a larger diameter require a greater tensile force for the riveting process.

From DE-PS 23 20 080 a setting tool for blind rivet nuts is known, in which the threaded mandrel in turn protrudes from the mouthpiece of the pistol-shaped housing and is fixedly connected to the pulling device which is rotatably and axially displaceably mounted in the housing. For the riveting process, the pulling device is moved axially in the housing by a drive, which is not described in detail. In order to facilitate the handling of the setting tool, especially when the blind rivet nut is being twisted onto the mandrel, and one operator's hand not by performing a double function, namely holding the To overwhelm the tool and the insertion of the threaded mandrel into the blind rivet nut and the simultaneous actuation of a drilling device while the other hand holds the blind rivet nut, a friction wheel is rotatably arranged on the side of the housing, which rotates with the pulling device through a recess in the housing, for example via a V-belt connected is. To untwist the blind rivet nut, the operator should then hold the blind rivet nut in one hand and the tool in the other hand, insert the mandrel into the blind rivet nut and roll the friction wheel against a wall or other friction surface so that it is transferred to the pulling device Rotational movement of the mandrel is screwed into the rivet nut. This solution cannot satisfy; This is because the friction wheel protruding from the side of the housing can be a hindrance for riveting work, especially in places that are difficult to access. After the riveting process has been completed, the friction wheel must be driven by hand in the sense that the mandrel is screwed out of the rivet nut again because the tool is connected to the material to be joined via the mandrel and the rivet nut. Really quick, energy-saving and time-saving work is not possible in this way because of the dependence on a suitable friction surface.

Also known are two different pneumatic-hydraulic riveting tools sold by the applicant for setting blind rivet nuts. By both of these devices, the device head comprising the mouthpiece and containing the pulling device is at a (right) angle to the pneumatic-hydraulic amplifier. After an unprocessed blind rivet nut (a blank) has been twisted onto the threaded mandrel of the pulling device protruding from the mouthpiece, the riveting process is brought about by actuating a pulling lever by admitting compressed air into a pneumatic chamber, where it presses a pneumatic piston against a restoring force. Connected to the pneumatic piston during this movement is a plunger plunging into a chamber filled with hydraulic medium. The displaced hydraulic medium acts against the force of a return spring on an annular piston surface of the pulling device within the device head and thus causes a pulling movement of the pulling device including the mandrel by an adjustable stroke. For the twisting and untwisting of the mandrel, one of these devices has a coiled twist rod that runs on balls in the extended device head, running on the longitudinal axis of the pulling device and connected to the extension of the threaded mandrel that protrudes into the device head and rotates relative to the pulling device and can be pushed or pulled by hand in both directions of rotation using a rotary knob, the threaded mandrel being rotated accordingly. In the other of the two devices mentioned, the thread mandrel is twisted on and off using a in the extended device head accommodated compressed air motor, which via a planetary gear and a twist coupling rotates the mandrel in the device head and relative to the traction device, with which there is a connection acting only in the axial direction. Compressed air is fed to the compressed air motor through a special air line via a regulator that can be adjusted by an air regulating screw, which, according to the actuation of two control valves accommodated in the device head between the air connection and the compressed air motor, is introduced into the compressed air motor for the right and left rotation for the twisting and untwisting process can. The control valves are actuated with the help of two trigger buttons arranged side by side on the device head. However, the last-mentioned device has the disadvantage that it places special demands on the skill of the operator in handling the device when the blind rivet nut is screwed on and off on the mandrel and the operator is basically overwhelmed in this respect because one has to open and close it Drilling actually requires "three hands". The unprocessed blind rivet nut (the blank) must be held in the left hand for the drilling; in your right hand you hold the blind riveting tool and insert the mandrel into the rivet shaft with an internal thread, and with it you have to press one of the two release buttons to initiate the pressure in the pressure Operate the air motor for the correct direction of rotation and you have to operate the trigger for the riveting process in order to allow compressed air to flow into the pneumatic-hydraulic amplifier. After the riveting process has been completed, the other release button for reversing the compressed air driving the compressed air motor must be actuated for the drilling process. All of this stands in the way of a quick, undisturbed workflow. The different actuation handles, which are to be carried out at the same time in part, require a great deal of attention and dexterity from the operator and make it necessary for the device for the up and down drilling process to be placed on a base in order to free one hand for actuating the release buttons . The device is equipped with a storage area on its pneumatic cylinder.

DE-OS 31 12 711 describes a pneumatic-hydraulic blind riveting device for setting blind rivets consisting of a rivet sleeve and a pull-off mandrel that can be torn off.

The object of the invention is to provide a lightweight and handy, easy-to-use, power-operated setting tool for blind rivet nuts, in which the up and down drilling more or less automatically, largely automatically, in connection with the processing of the blind rivet nuts the actual riveting process takes place, whereby great time savings can be achieved in the setting process and the operator is considerably relieved. The device should therefore have an actuating device which reduces the number of necessary switching operations to be carried out by the operator compared to the known devices. The device should work in an energy-saving manner and it should be able to process all commercially available thread sizes of blind rivet nuts in all possible materials such as aluminum alloy, steel, stainless steel, brass, etc.

This object is achieved in that the valve arrangement is assigned a control valve which is connected to the compressed air motor and that after the riveting process has been completed, the compressed air motor can be connected to the pneumatic chambers of the pneumatic part of the translation system by relieving the actuating member.

The control valve can be switched on in a pneumatic connection between the compressed air source and the compressed air motor.

The control valve can preferably be actuated by pressure.

In a preferred embodiment, the valve body of the control valve protrudes to a certain extent from its housing in the rest or shut-off position.

Advantageously, an actuating lever extending over the control valve is pivotally articulated laterally on the housing of the control valve, which engages with light pressure on its free end against the valve body projecting from the valve housing, as a result of which the control valve can be actuated.

In a further advantageous embodiment, the control valve can be arranged in a valve housing which can be rotated around the housing of the compressed air motor.

By actuating the control valve switched into the pneumatic connecting line between a first inlet opening of the compressed air motor and the compressed air source, compressed air can be supplied to the compressed air motor for rotation in one direction of rotation before the actual riveting process, and it can be used for the riveting process itself in the pneumatic-hydraulic After the riveting process has been carried out and / or after the traction device has been reset, the compressed system can be fed to the compressed air motor through a second inlet opening for rotation in the other direction of rotation.

This means that only one actuating means has to be operated for the drilling process and for the actual riveting process itself. The drilling process takes place automatically after the riveting process by redirecting the compressed air stored during the riveting process, this being additionally used twice in an advantageous manner.

By turning the valve housing around the motor housing, the valve or its actuating lever can be brought into the most favorable position for actuation. The actuating lever, which is only to be operated for the twisting-on process, does not have to be operated from the edge, but can, after being brought into the correct position by turning the valve housing, by light pressure, e.g. against the chest, in front of which the operator holds the device anyway during the twisting process, or against the forearm. This relieves the hands of the operator, and it is possible to work quickly and undisturbed without having to put the device out of his hand for the up and down drilling process in order to press buttons for reversing the compressed air to the compressed air motor. The operator can concentrate entirely on the actual point of his work on the material to be joined, and his attention is not claimed by the actuation of several actuating means and by various manipulations associated with this on the device.

The control valve is preferably a 3/2-way valve.

In an advantageous embodiment of the invention, between the outer wall of the motor housing and the inner wall of the valve housing of the control valve, which is rotatable about the same, there is an annular space which is sealed on both sides and is constantly connected to the compressed air source by a pneumatic connection; In this annular space opens a hole penetrating the wall of the valve housing, in which the valve body of the control valve is slidably arranged, and from this hole a connecting hole leads to another, sealed on both sides annular space between the outer surface of the motor housing and the inner surface of the valve housing and from there connecting holes in the motor housing and in the one bearing flange of the compressed air motor to its first inlet opening.

Both the inner edge and the outer edge of the bore penetrating the wall of the valve housing can be designed as a valve seat for the valve body of the control valve; on the inner valve seat located in the annular space, the valve body interrupts the connection between the first inlet opening of the compressed air motor and the compressed air source in its unactuated position, and in its actuated position it produces it; on the outer valve seat, in its unactuated position, it establishes the connection between the first inlet opening of the compressed air motor and the atmosphere and interrupts them in its actuated position.

The annular space between the motor housing and valve housing is advantageously expanded in the region of the bore receiving the valve body of the control valve by an annular groove in the inner surface of the valve housing and / or in the outer surface of the motor housing.

In another, preferred embodiment of the setting tool for blind rivet nuts according to the modified variant described above, the control valve can be actuated by compressed air.

The control valve can be integrated in the device head and consist of a valve housing with a valve body arranged coaxially movable therein.

The valve body of the control valve can be actuated by means of an actuating element which is arranged in the region of or near the actuating element (s) for initiating the riveting process of the setting tool and which is accommodated, for example, in the hand protection of the setting tool.

The valve body can advantageously be actuated by connecting compressed air by means of its actuating member.

In this case, the actuating member for the control valve can be arranged in a bore in, on or near the tool head of the setting tool, and means can be provided by means of which a compressed air flow can be prevented.

The actuating element of the control valve can consist of at least one sleeve, by means of which a pressure spring can be brought into the block position by finger pressure and the compressed air flow can thus be prevented.

In this embodiment, there is preferably a pneumatic connection from the actuating member to the valve body of the control valve and from there to an inlet opening to the rotor of the compressed air motor, and the pneumatic connection between the actuating member of the control valve and the one inlet opening to the rotor of the compressed air motor can in turn provide a pneumatic connection to the compressed air source to have.

The valve body of the control valve can advantageously be kept in the starting position (ready position) by means of compressed air.

For this purpose, an annular space closed at its rear end can exist between the valve body and valve housing, the valve body in this annular space approximately in its central region against the Be sealed valve housing and have an external gradation behind this seal and compressed air from the pneumatic connection to the compressed air source can be introduced into the subspace of the annular space thus formed.

When compressed air is switched on by means of the actuating member of the control valve, the valve body can be movable into its switching position in order to initiate the untwisting of the blind rivet nut due to the area ratio between the front surface and the smaller area of the outer gradation of the valve body.

With the above-described embodiment of the setting tool for blind rivet nuts, an actuating means must also be operated for the drilling process and for the actual riveting process, and the drilling process takes place automatically after the riveting process by redirecting the compressed air stored during the riveting process, which is also more advantageous - Used twice. However, there may be a very welcome additional advantage that the actuator for the control valve is located in the area of the actuator of the setting tool for initiating the riveting process, in the exemplary embodiment in the hand protection of the setting tool, so that without the loading servant would have to change the handle of the hand on the setting tool, they can operate the actuator for the control valve with the same finger of the same hand with which they actuated the actuator for initiating the riveting process.

In both of the above-described embodiments of the setting tool for blind rivet nuts, there is preferably a pneumatic connection from the second inlet opening of the compressed air motor to the one connection of the valve arrangement, by actuating it for the actual riveting process, compressed air into the one located on the back of the pneumatic pressure piston of the pneumatic-hydraulic translation system Pneumatic chamber can be introduced, and in its initial position, the valve arrangement connects the pneumatic chamber located on the rear side of the pneumatic pressure piston to the pneumatic connecting line to the second inlet opening of the compressed air motor, while it separates it from it in the actuated state. The drilling process is inevitably connected to the actual riveting process and automatically follows it, because both processes are controlled by the valve arrangement in its two positions, and even the compressed air of the riveting process is used.

The pneumatic connection between the second one The opening of the compressed air motor to the one connection of the valve arrangement can be through a longitudinal bore in the motor housing, the housing space behind the pulling device for the threaded mandrel, through the pulling device into a surrounding housing ring space of the device head, sealed in both longitudinal directions, and from there through a hole in the housing of the pneumatic-hydraulic transmission system. In this way, the connection runs in an advantageous and space-saving manner in the housing and between parts of the device, and there are no annoying connecting lines on the outside of the device.

For this purpose, the pulling device can advantageously be constructed in several parts and essentially consist of a hollow pulling piece, in one end of which the threaded mandrel protruding from the mouthpiece of the device head is screwed in and in the other end a shaft which can be driven by the compressed air motor engages, and one this traction piece, leaving a fit space in a ring-surrounding traction piston which can be moved tightly on the housing wall, the traction piece bearing a stop ring in front of the pull piston and the pull piston resting in the opposite direction on a stop (a casing ring arranged in the housing and sealed against the housing wall) can and the fit space part of the pneumatic connection between represents the second inlet opening of the air motor and the valve assembly.

Preferably, the pulling piston, opposite to the pulling direction, has a tubular extension, which also maintains the fitting space with respect to the pulling piece, against which the hydraulic chamber containing the hydraulic loading surface of the pulling piston is sealed by a (rod) seal arranged in the stop (casing ring), the connecting bore from The hydraulic chamber of the pneumatic-hydraulic booster opens the hydraulic chamber and the connecting hole leading to the valve arrangement into the housing ring space on the other side of the stop (casing ring).

In the pulling direction in front of the pulling piston, an annular return piston, which can be pressurized with compressed air against the pulling direction, is advantageously arranged so as to be tightly displaceable against the housing wall and the pulling piece, and an annular space surrounded by it and open to the pulling piston and thus to the fit space is provided with a duct pipe which projects through the pneumatic chamber between the reset piston and the motor housing a connecting bore leading to the second inlet opening of the compressed air motor in the motor housing.

In a further embodiment of the invention, there can be a pneumatic connection between the second inlet opening of the compressed air motor and the compressed air source, into which a compressed air can be actuated (opened) which is closed in the rest position and after the riveting process has been completed by the compressed air previously introduced and stored in the pneumatic-hydraulic translation system for the riveting process ) Make-up valve can be switched on. The compressed air previously stored in the pneumatic-hydraulic transmission system is sufficient to remove normal blind rivet nuts. However, the make-up valve provided according to the invention ensures that additional compressed air for the drilling process, namely from the compressed air source, is automatically supplied, so that e.g. Blind rivet nuts of longer lengths in all common sizes, e.g. M3 to "M12; and in all common materials such as aluminum alloys, steel, stainless steel, brass etc. can also be processed.

The make-up valve preferably has a valve body designed as a differential piston, the smaller application area of which lies in a valve chamber at the bottom of the valve housing that is permanently connected to the compressed air source, and the larger application area of which after the riveting process has been completed by the valve arrangement with the pneumatics located on the rear side of the pneumatic pressure piston chamber of the pneumatic-hydraulic translation system connectable space. After the riveting process has been completed, the valve body of the make-up valve is automatically lifted from its seat due to the area ratio of its application surfaces, and the make-up connection between the compressed air motor and the compressed air source is established.

The larger area of action of the valve body can be in the pneumatic chamber located in front of the pneumatic pressure piston.

The actuation stroke and thus the closing time of the valve body can advantageously be set by an externally accessible adjusting screw on the bottom of the valve housing or the valve chamber.

The valve body of the make-up valve can be displaceable in a stepped valve cylinder and, when the valve body is raised, can be moved with the valve chamber on the housing base, i.e. annular space connected to compressed air can be connected through bores in the valve cylinder to an annular space in the lateral surface of the valve cylinder, which in turn is connected to a pneumatic connecting bore.

The make-up valve is preferably a 2/2-way valve.

The valve arrangement already mentioned at the beginning can be a 4/2-way valve.

Further details and advantages of the invention result from the following description of a preferred embodiment of the invention with reference to the attached drawing.

• Fig. 1 shows schematically the overall view of the setting tool according to the invention.
• 2a and 2b together show a longitudinal section through the setting tool according to the invention on an enlarged scale compared to FIG. 1, the left-hand side of FIG. 2b being immediately to the right of FIG. 2a.
• 3 shows, on a scale enlarged compared to FIGS. 2a and 2b, a cross section through the setting tool according to the invention along the line CD in FIG. 2b, viewed in the direction of the arrow, the parts belonging to the hydraulic part of the pneumatic-hydraulic translation system being omitted are.
• FIG. 4 shows a section through the setting tool according to the invention along an enlarged scale compared to FIGS. 2a and 2b 3 in the line of sight indicated by the arrows, in particular a longitudinal section through the make-up valve according to the invention lying in one of the several sectional planes.
• Fig. 5 shows a longitudinal section through the tool head and part of the handle of another embodiment of the setting tool according to the invention according to Fig. 2a (and on the same scale as this), in which the actuating member for the control valve is arranged in an area near the actuating member for the setting tool is.
• FIG. 6 shows, on an enlarged scale compared to FIG. 5, a cross section through the setting tool according to the invention along the line EF in FIG. 5, viewed in the direction of the arrow, with the housing of the tool head, adapter and sleeve indicated.

Fig. 1 shows schematically an overall view of the setting tool according to the invention on a scale of 1: 2 of a device of natural size, such as is placed on a footprint such as a table. The setting tool, which has a pneumatic-hydraulic drive, consists of the tool head A, from which the threaded mandrel 7 protrudes, the hydraulic one Part of the drive system enclosing handle B and the pneumatic part C. Furthermore, 96 the compressed air hose, via which the setting tool is connected to a compressed air source, 119 'the control button for initiating the riveting or setting process, 62 the actuating lever for the control valve 55 in Fig 2a and 128 a hand protection. D is a suspension bracket for the setting tool.

2a and 2b show the details of the setting tool in longitudinal section.

The essentially hollow cylindrical housing 1 of the device head A is preferably made of hard-coated aluminum. At its front end, with the aid of an adapter 5 and secured by a locking ring and a cylindrical pin, a sleeve 3 with an inner diameter reduced by a certain amount compared to the housing 1 is fastened, which preferably consists of steel. The inner diameter of the sleeve 3 is reduced again at its front end by a gradation, and in this area, with the help of a lock nut 6, this is for different thread sizes (metric, in inches or in another thread dimension) of blind rivet nuts - for example from M3 to M12 (Thread diameter from 3mm to 12mm) - interchangeable mouthpiece 2 screwed in. A hollow cylindrical tension piece 4, whose outer diameter is significantly smaller than the inside diameter of the mouthpiece 2, extends from directly behind the narrowed opening of the mouthpiece 2 coaxially into the housing 1. The threaded mandrel 7 projects from the narrowed opening of the mouthpiece 2. The threaded mandrel 7 in the exemplary embodiment is a corresponding to the various Sizes of blind rivet nuts - e.g. from M3 to M12 - also interchangeable DIN screw with hexagon socket, which is screwed into the front end of the tension piece 4, which has an internal thread in this area. A hexagon rod 8, which extends coaxially within the hollow tension member 4, is snapped into the hexagon socket as a spline shaft in the exemplary embodiment, which, as will be explained further below, can be driven by a compressed air motor and rotated in both directions of rotation, the threaded mandrel 7 also rotating. The hexagonal rod 8 is guided in the traction element 4 by means of a guide 8 'so that it cannot rotate. In the exemplary embodiment, the guide 8 'is a screw with an internal hexagon and an external thread, which engages in an internal thread present there in the tension piece 5, wherein the guide 8' and tension piece 4 can be glued together in the area of this thread for the purpose of secure adhesion. The compression spring 50 rests on the guide 8 '. The hexagonal rod 8 is also fixed within the tension piece 4 with the aid of a tightly fitting locking piston 48. Between the locking piston 48 and, as already mentioned, the Guide 8 'is arranged the compression spring 50 surrounding the hexagonal rod 8. The hexagonal rod 8 and the locking piston 48 are firmly connected to one another in the exemplary embodiment. At a distance from the locking piston 48 there is a stopper 49 with a central bore inside the hollow tension member 4, through which, when the device is connected to compressed air, compressed air can penetrate, which acts on the locking piston 48 and thus the compression spring 50 as in FIG. 1 shown keeps excited. If the device is completely separated from the compressed air source, the compression spring 50 relaxes, and the locking piston 48 moves up to the stopper 49. At the junction of the mouthpiece 2 with the sleeve 3, the end of the mouthpiece 2 forms together with a step in the inner wall the sleeve 3 has an annular surface, behind which a thrust bearing for the tension member 4 is arranged. The bearing balls 9 are located between a thrust washer 4 enclosing and resting on the said annular surface and a pressure ring 11 secured by a snap ring on the outer surface of the tensile member 4. At a distance from the ball bearing and in the area of the connection between the sleeve 3 and the Housing 1 is a hollow cylindrical part 12 which surrounds the pulling element 4 at a short distance, the outer surface of which is stepped and which is held at this step on an undercut 13 of the inner wall of the housing. In its radially larger Be rich is this hollow cylindrical part 12 sealed on its outer wall against the inner wall of the housing and on its inner wall against the tension member 4 in each case by an O-ring lying in an annular groove. While maintaining a fit space 14, the pull piece 4 is surrounded by a pull piston 15 designed as an annular piston, which in the direction of the mouthpiece 2 has a tubular extension 16 that maintains the same fit space 14 and ends at a distance from the hollow cylindrical part 12. On its outer surface, the tension piston 15 is sealed against the housing wall 1 by means of a piston seal (groove ring) 17. An annular piston 18 is fastened to the tubular extension 16 of the pulling piston 15 shortly before its end by means of a securing ring. The outer diameter of the annular piston 18 is significantly smaller than the inner diameter of the housing 1 surrounding it. A 0-ring 22 is located in a groove in the outer surface of the annular piston 18. In the starting position of the device, the pulling piston 15 lies with its one annular surface firmly on the housing 1 arranged jacket ring 19, which is sealed against the housing wall with an O-ring 21 and against the tubular extension 16 of the tension piston with a rod seal 23. Below the jacket ring 19 there is a thin-walled cylinder sleeve 24 with its jacket surface resting against the housing wall, the inside diameter of which at its end facing the jacket ring 19 and resting against it by an end Paragraph 25 is reduced to the outer diameter of the tubular extension 16 of the tension piston 15. In an annular groove of this paragraph 25 there is an O-ring 26 sealingly attached to the tubular extension 16. The cylinder sleeve 24 extends shortly before the annular piston 18. As will be described in more detail below, the annular piston moves during an actuation stroke of the pull piston 15 18 into the cylinder sleeve 24, the 0-ring 22 then sealingly engaging the inner wall of the cylinder sleeve 24 and sealingly separating the annular spaces lying inside the cylinder sleeve 24 in front of and behind the annular piston 18.

In the direction of actuation in front of the pulling piston 15, a stop ring 27 is fastened to the pulling piece 4 projecting through it with the aid of a snap ring, against which the pulling piston 15 strikes during an actuating stroke and in this way can pull the pulling piece 4 with it when it moves. In addition, in front of the pulling piston 15, lying on its annular surface, the annular return piston 28 is arranged, which is sealed on its outer surface by an O-ring 29 against the housing wall and whose inside diameter is larger than the outside diameter of the stop ring 27. At a distance from the stop ring 27, the inner diameter of the restoring piston 28 is reduced to the outer diameter of the pull piece 4 by a radial projection and here against the outer surface of the pull piece 4 by a 0-ring 30 sealed so that an annular space 31 lying in front of the tension piston 15 and essentially delimited by the return piston 28 is created, which has a connection with the fit space 14 between the tension piston 15 and tension piece 4. The pull piece 4 ends a little behind the return piston 28. At a distance from the return piston 28, the motor housing 32 is inserted, preferably screwed, into the end of the housing 1, in which the twist drive for twisting the blind rivet nut up and down on and from the threaded mandrel 7 located. A valve housing 33 is arranged to rotate freely around the motor housing 32, a small annular space 52 remaining sealed off to the outside by O-rings 34, 35 remaining between the outer wall of the motor housing 32 and the inner wall of the valve housing 33. At the end of the motor housing 32, a bearing flange 36 for the compressed air motor 37, 38 is sealed against its inner wall. The second bearing flange 39 is located in the cylindrical end section 43 of the motor housing 32. The cylindrical end section 43 of the motor housing 32 has an external thread and is closed by a screw cap 41. Between the screw cap 41 and the valve housing 33 there is the muffler 40, which here forms a further part of the housing of the device head A in the region of the compressed air motor 37, 38. In the interior of the motor housing 32 between the two bearing flanges 36 and 39 is the one from the rotor 37 with the rotor blades 42 and the stator 38 existing air motor. The two ends of the stator 38 are fitted in the motor housing 32. The rotor shaft is rotatably supported in the ball bearings housed in the bearing flanges 36 and 39. A pinion 44 protrudes from the rotor shaft into the motor housing 32 and engages with a planetary gear 45 accommodated there. The planet carrier 46 is rotatably mounted in the motor housing 32 and continues as a shaft which extends through the central housing bore of the motor housing 32. The shaft is sealed against the wall of the bore at a narrowed point in the housing bore. In the exemplary embodiment, the shaft merges into a hexagonal shaft 47, which can also be a spline shaft. It protrudes through the motor housing 32 into the housing 1 of the device head A, where it engages with the tension piece 4, which is designed as an internal hexagon in its end section in the exemplary embodiment. In this way, can be driven by the air motor 37, 38 via the planetary gear 45, the hexagonal shaft 47 and the tension member 4 of the hexagonal rod 8 fixed within the tension member 4, which itself is in engagement with the hexagon socket of the mandrel 7 and consequently for the opening - and unscrewing the blind rivet nut turns. So that the compressed air motor 37, 38 can be driven once to the right and once to the left to twist it up and down, it has two different inlet openings for the compressed air driving it.

The interior of the motor housing 32, which receives the planetary gear 45, is connected to the through a lateral longitudinal bore in the motor housing 32, in which a channel tube 51 is tightly displaceable, which projects with its other end into a connecting bore in the return piston 28 opposite the motor housing 32 annular space 31 enclosed by reset piston 28.

The small annular space 52 between the motor housing 32 and the valve housing 33 which is rotatable about the same and which has bores 60, 61 in the motor housing 32 in connection with the space 73 between the motor housing 32 and the return piston 28 is approximately halfway up the valve housing 33 through an annular groove in the inner wall of the valve housing 33 and possibly expanded by a second annular groove in the outer wall of the motor housing 32 that overlaps this annular groove. Above this enlarged annular space 52 ′, the valve housing 33 is sealed against the motor housing 32 by an O-ring 53 lying in an annular groove. A valve bore 54 which penetrates the wall of the valve housing 33 and into which the valve body 55 of the control valve is inserted opens into the enlarged annular space 52 '. Both the edge of the valve bore 54 on the outer wall of the valve housing 33 and the edge on the enlarged annular space 52 'are designed as valve seats, on which the valve body 55 depends Actuating position can sit sealingly. In the rest position of the valve body 55, it seals on the inner valve seat of the enlarged annular space 52 '. If the valve body 55 is pushed into the valve bore 54 by pressure from the outside, it lifts off the inner valve seat and comes into sealing contact with the outer valve seat on the outer wall of the valve housing 33. A longitudinal bore 56 leads from the valve bore 54 into a further annular groove 57 located above the seal (0-ring) 53 in the inner wall of the valve housing 33. From this annular groove 57, a transverse bore 58 in the motor housing 32 leads further into a blind bore 59 in the front Bearing flange 36 of the compressed air motor 37, 38, which has a connection to the first of the two inlet openings of the compressed air motor 37, 38.

To actuate the control valve, i.e. of the valve body 55, an actuating lever 62 is pivotally articulated on the side of the valve housing 33, which, as soon as it is moved towards the valve housing 33, bears against the valve body 55 which protrudes from the valve bore 54 to a certain extent and, upon further actuation, into the valve bore 54 pushes in. It is a 3/2-way valve.

An essentially cylindrical extension 63 of the housing 1 projects laterally from the device head A. This Extension 63 is surrounded by the handle B, leaving an intermediate space 64, which is flared at both ends. From the free end of the extension 63, it is screwed to it and consequently to the housing 1 with the aid of a sealing ring socket 65. The intermediate space 64 is sealed on the sealing ring frame 65 by sealing rings 66, 67 against the inner wall of the grip piece B and by a sealing ring 68 against the outer wall of the extension 63. The sealing ring 68 also prevents hydraulic medium from entering the intermediate space 64 from the hydraulic space 69, which is formed by a cylindrical bore in the extension 63. The space 64 is widened at the joint between the handle B and the device head A on the side facing the compressed air motor 37, 38 to form a cavity 70 and sealed to the outside by a flat seal 71. A bore 72 in the wall of the device head A connects to the annular space 73 between the motor housing 32 and the reset piston 28 in the housing 1.

The already mentioned hydraulic chamber 69, formed by a blind bore in the extension 63 of the housing 1, has a bore 74 connecting it to the hydraulic chamber 75 located in the housing 1 between the casing ring 19 and the tension piston 15. Outside the extension 63, in the drawing of the connecting bore 74 directly Opposite, a refill hole to the hydraulic chamber 75 is provided in the housing wall 1, which is sealed by a refill screw 76 and with the help of a sealing ring 77. Hydraulic medium can be refilled easily through this refill hole if the refill screw 76 has been removed, without any complicated assembly work.

The cylinder pot 79 of the pneumatic part C of the drive system is connected to the flange of the handle B facing away from the device head A by means of eight long screws 78. The cylinder pot is preferably made in several pieces. According to FIG. 2b, it consists of the actual cylinder pot 79a, a jacket 79b surrounding it and a base plate 79c, into which the screw heads of the screws 78 are countersunk. A stand rubber 80 running around the bottom of the cylinder pot also covers the screw heads and also partially encompasses the casing 79b. If the device is out of operation, it can advantageously be placed upright on the bottom of the cylinder pot, ie the base plate 79c or the rubber stand 80. A central opening is provided in the bottom of the cylinder pot 79a and in the bottom plate 79c which is in contact with it from the outside, and with the cylinder pot bottom is a compensating piston 81 which is open on both sides and is coaxial with the cylinder pot 79 firmly connected, which protrudes through the entire cylinder pot 79 into the flange part of the handle B. In the illustrated embodiment, the central opening in the bottom of the actual cylinder pot 79a is bent inwards and the hollow compensating piston 81 is held therein.

An annular disk-shaped pneumatic pressure piston 82 is arranged in the cylinder pot 79 so as to be tightly displaceable against the cylinder wall. Its inner diameter is larger than the outer diameter of the compensating piston 81, and coaxial to the compensating piston 81 and to the pneumatic pressure piston 82, a hollow plunger 83 is fixedly connected to the latter, with its closed, free end through the central opening of the sealing ring holder 65 into the Hydraulic medium-filled hydraulic space 69 protrudes. The hydraulic chamber 69 is through a rod seal 84 between the sealing ring socket 65 and the plunger 83 against the pneumatic cylinder cup 79 and through the already mentioned sealing ring 68 between the outer wall of the housing extension 63 and the sealing ring socket 65 screwed thereon against the intermediate space 64 between the housing extension 63 and the handle B sealed. Between the rod seal 84 and a radial one. inward extension 86 of the sealing ring socket 65, a guide ring 85 for the plunger 83 is arranged. On the one facing the pneumatic cylinder 79 On the side of the extension 86, a sealing ring 87 which tightly surrounds the plunger 83 is located in the sealing ring socket 65 and seals the pneumatic chamber 88 lying in front of the pneumatic pressure piston 82 in the actuating direction. The compensating piston 81, which concentrically projects into the hollow plunger 83 while maintaining a radial space, is sealed at its free end against the inner wall of the plunger 83. In the embodiment shown in the drawing, the compensating piston 81 consists of two parts, namely a relatively thin-walled tube 81a, which is fixedly connected to the bottom of the cylinder pot, and a sleeve 81b pushed onto the free end of the tube 81a _' , in the outer wall of which the Annular groove for the sealing ring 89 sealing against the inner wall of the plunger 83.

The open end of the plunger 83 connected to the annular pneumatic pressure piston 82 is inserted into the central opening of the pressure piston 82. On the side lying in the actuating direction of the pressure piston 82, there is a stop ring 90 lying thereon and surrounding the plunger 83, which is held and secured in place by a snap ring 91.

In the part of the handle B facing away from the device head A and its part connected to the cylinder pot 79 The pneumatic control for the drive of the device is housed in the flange. In the reinforced flange part there is a 4/2-way pneumatic valve 92, preferably negative control, lying transversely, not visible in FIG. 2b. Fig. 3, which shows a cross section through the flange part along the section line C - D in Fig. 2b, shows a longitudinal section through this 4/2-way valve 92. Fig. 3 shows the cross section through the flange part of the handle B, before it is pushed onto the lateral extension 63 of the housing 1, so that the central circular line E in Fig. 3, the outer wall of the space 64 between the handle B and the extension 63 according Fig. 2a marked. Laterally on said flange part is connected in a stepped bore 93 by means of a connecting sleeve 94 and a connecting sleeve 95, the compressed air hose 96, which can also be seen in FIG. 2b, the other end of which is connected to a compressed air source. The connection bore 93 has through bores direct connection to the intermediate space 64 at 97, to a cylindrical opening (valve housing) 98, in which a refill valve 120 according to the invention, described in more detail below with reference to FIG. 4, is accommodated at 99 and to the cylindrical opening (valve housing ) 100, in which the 4/2 - \ 'ege valve 92 is housed, at 101. The valve housing 100 is divided into two sections with different diameters by a bevel in the wall knife divided. At the bottom of the section with the smaller diameter, the connection 101 opens laterally from the compressed air connection bore 93. In the further section of the valve housing 100, a control cylinder 102 is accommodated, which is closed on its side facing away from the bottom of the valve housing 100, but towards the bottom is open. In its outer wall, the control cylinder 102 has an annular groove 103; on both sides of this annular groove 103 it is sealed against the wall of the valve cylinder 100 by sealing rings. The annular groove 103 is connected through a bore 104 in the wall of the control cylinder 102 to the cylinder space 105 thereof. A control slide 106 is tightly displaceable in the cylinder space 105 of the control cylinder 102 and projects into the narrower section of the valve housing 100, on the bottom of which it can come to rest against a stop disk 107. The spool 106 has four sections with three different diameters; The first section with the largest diameter, which is tightly guided in the control cylinder 102, is followed by a second section reduced by a gradation to a smaller diameter, and this is followed by a third section, which is reduced in diameter by a bevel, and this is followed by the second section Diameter of the second section expanded fourth section. If the control slide 106 rests on the housing base, there are its second to fourth section in the narrower part of the valve housing 100. The control slide 106 is pierced in the longitudinal direction from both sides; the two boreholes are connected to one another by a throttle opening 108, through which the cylinder space 105, via the bore 104 the annular groove 103 and an invisible bore are supplied with compressed air which is present at the valve 119, 119 '. The throttle opening 108 is dimensioned such that it prevents the outflow of an undesirable excess of compressed air through the valve 119, 119 'to the outside when the valve 119, 119' is actuated. In the narrower part of the valve housing 100, three receiving rings 109, 110, 111 are arranged, one 109 a short distance from the housing base, one 110 directly at the end of the narrower part of the valve housing 100 and one 111 approximately in the middle between the receiving ring 109 and the receiving ring 110. Each of the receiving rings 109, 110, 111 is sealed on its outer surface against the valve housing 100 and also has an annular groove in its inner surface, in each of which there is a sealing ring sealing against the second and fourth sections of the control slide valve -106. There are thus four valve spaces, the first 112 between the housing base and the first receiving ring 109, the second 113 between the first 109 and the middle receiving ring 111, the third 114 between the middle 111 and the last receiving ring 110, and the fourth 115 arises from a recess in the wall of the control cylinder 102 resting on the last receiving ring 110 with its annular surface. These four valve spaces 112, 113, 114, 115 are connected to one another or separated from one another in different ways, depending on the position of the control slide 106. The first valve chamber 112 is connected to the compressed air connection through the connecting bore 101 opening at the bottom of the valve housing 100. The second valve chamber 113 is connected to the pneumatic chamber located on the back of the pneumatic pressure piston 82 in the pneumatic cylinder 79. This connection is established by a channel tube 117 which extends longitudinally through the cylinder pot 79 and passes through the pressure piston 82. An annular groove running in the through opening of the pressure piston 82 receives a sealing ring 118 which seals against the outer surface of the channel tube 117, so that the pressure piston 82 moves is tightly guided on the sewer pipe 117 (see Fig. 2b). The third valve chamber 114 is connected to the pneumatic chamber 88 located in front of the pneumatic pressure piston 82 and also (see FIG. 2a) via a bore 116 in the handle B, which comes from the pneumatic chamber 88 at the joint between the handle sealed by an annular seal B and device head A continues in the latter, and by a puncture in the cylinder sleeve 24 arranged in the housing 1 with that surrounded by this cylinder sleeve 24 Annulus. The puncture opens directly under the paragraph 25 of the cylinder sleeve 24 in this annular space. The fourth valve chamber 115 is connected to the atmosphere. The annular space 103 formed by the annular groove 103 in the circumferential surface of the control cylinder 102 is connected to a 2/2-way valve 119, which can be actuated by the actuating member designed as an operating button 119 ', via a connecting bore which is not visible in the drawing. The preferably negative control of the control slide 106 in the cylinder space 105 of the 4/2-way valve 92 described above takes place via the annular space 103 and the bore 104 in the wall of the control cylinder 102.

According to the invention, a pressure-area-dependent make-up valve 120 is also arranged in the flange part of the handle B connected to the cylinder pot 79 in a longitudinally extending valve housing 98. This make-up valve 120 can be seen in the longitudinal section in the sectional drawing according to FIG. 4 following the broken section line A - B in FIG. 3, that is to say as it is represented in a broken longitudinal section through the flange part of the handle piece B.

In a cylindrical valve housing 98 open in the direction of the pneumatic chamber 88 lying in front of the pneumatic pressure piston 82 in the cylinder pot 79, with the The cylinder part 79 connected to the flange part of the handle B is pressed in a valve cylinder 121 which bears on its two end sections against the valve housing 98 and has a circumferential recess between the two end sections in its lateral surface which forms an annular space 122 with the wall of the valve housing 98. This annular space 122 is connected to the pneumatic chamber 88, which in turn has a connection with the pneumatic connection bore 116 in the handle B (see FIG. 2a) when the 4/2-way valve 92 is in the appropriate position. By stepping to about half the height of its inner wall, the valve cylinder 121 has two sections with different wall thicknesses. The thin-walled section is the pneumatic chamber 88, the section with the thicker wall faces the bottom of the valve housing 98. Between the bottom of the valve housing 98 and the valve cylinder 121 there is an intermediate space 123 (valve space), which has a permanent connection to the compressed air connection 93 through the bore 99 visible in FIG. 3. The annular space 122 is connected to its narrow cylinder space by at least one, preferably two or more connecting bores 124 in the thick-walled section of the valve cylinder 121. The inner edge of the annular surface of the valve cylinder 121 facing the bottom of the valve housing 98 is designed as a valve seat, and a difference that is displaceable in the valve cylinder 121 Piston-shaped valve body 125 can rest on this valve seat with a sealing surface formed at one end, for example a sealing ring located in an annular groove, so that the intermediate valve space 123 is tightly separated from the interior of the valve cylinder 121. Behind this valve seat, the essentially cylindrical and in the form of a stepped piston valve body 125 has an annular groove in the area of the connecting bores 124 of the thick-walled section of the valve cylinder 121, which forms an annular space 126 with the inner wall of the valve cylinder 121, which through the connecting bores 124 connects with the Annulus 122 is connected between the outer surface of the valve cylinder 121 and the valve housing 98. The annular space 126 can be sealed on the one side on the valve seat described above and on the other side on the lateral surface of the valve body 125 against the inner wall of the thick-walled section of the valve cylinder 121 with the aid of a sealing ring. Behind this seal, the valve body 125 extends into the thin-walled section of the valve cylinder 121 and is only radially expanded at its end at a distance from the step in the inner wall of the valve cylinder 121 and sealed against the cylinder wall. The distance between the widened end of the valve body 125 and the gradation of the cylinder inner wall allows the valve body 125 in the valve cylinder 121 to be displaced into the opening direction of the valve formed at the other end as described above.

Opposite the valve body 125, the bottom of the valve housing 98 is pierced in the flange part; An externally accessible adjusting screw 127 is screwed into this bore, with which the stroke of the valve body 125 can be adjusted.

Provided underneath the handle B is a hand guard 128 which extends from the device head A to the flange part of the handle B connected to the pneumatic cylinder 79 (cf. also FIG. 1).

The preferred use of plastic for various components of the device, such as the handle B, the handguard 128 and the cylinder pot 79, together with light metal (aluminum) for various metal parts, such as the housing 1 and other parts in the device head A, the entire device is light and yet extremely powerful. It has a pulling force of around 1.5 tons and can process all common sizes of blind rivet nuts.

The use of plastic for various components has the particular advantage that they are injection molded as plastic molded parts which can then be assembled without post-processing. In addition, these plastic parts can be colored as external parts in the desired color during manufacture, so that the device does not have to be painted.

The plastic used is preferably a glass fiber reinforced plastic made from one of the polyamides.

• Die Zeichnung Fig. 2a und Fig. 2b zeigt das Setzgerät bzw. die anhand Fig. 3 und 4 beschriebenen Ventile (4/2-Wege-Ventil 92, Nachspeiseventil 120) in Bereitschaftsstellung, d.h. bei über den Druckluftschlauch 96 anstehender Druckluft aus einer Druckluftquelle, aber im unbetätigten Zustand des Gerätes. Das 4/2-Wege-Ventil 92 arbeitet, wie bereits erwähnt, mit negativer Steuerung; bei unbetätigtem Bedienungsknopf 119' steht Druckluft von der Druckluftquelle durch den Druckluftschlauch 96 über die Verbindungsbohrung 101, den durch den ersten Aufnahmering 109 begrenzten ersten Ventilraum 112, die Drosselöffnung 108, den Zylinderraum 105, die'Bohrung 104, den Ringraum 103 und die nicht sichtbare Bohrung am Ventil 119, 119' an. Dabei beaufschlagt sie in dem Zylinderraum 105 des 4/2-Wege-Ventils 92 die größere Beaufschlagungsfläche des Steuerschiebers 106 und hält diesen in der in Fig. 3 gezeigten Stellung, und die Druckluft beaufschlagt dort die kleinere Ringfläche des Steuerschiebers 106. Wegen des Flächenverhältnisses der beiden entgegengesetzten Flächen des Steuerschiebers 106 wird dieser aber in der dargestellten Stellung gehalten. In dieser Stellung sind die beiden entfernt voneinander liegenden Ventilräume des 4/2-WegeVentils 92, der mit Atmosphäre in Verbindung stehende Ventilraum 115 und der mit Druckluft verbundene Ventilraum 112 durch die Dichtwirkung der von den beiden voneinander entfernt liegenden Aufnahmeringen 109, 110 getragenen Dichtung an den beiden Abschnitten mit dem mittleren Durchmesser des Steuerschiebers 106 gegenüber den beiden zwischen ihnen liegenden Ventilräumen 113, 114 abgedichtet, während diese beiden benachbarten Ventilräume, von denen der eine 113 mit der Pneumatikkammer auf der Rückseite des Pneumatik-Druckkolbens 82 und der andere 114 mit der vor dem Druckkolben 82 liegenden Pneumatikkammer 88 und außerdem mit der pneumatischen Verbindungsbohrung 116 im Griffstück B verbunden ist, auch miteinander Verbindung haben, weil sich der Abschnitt des Steuerschiebers 106 mit dem geringsten Durchmesser im Bereich des mittleren Aufnahmerings 111 befindet, hier also keine Abdichtung stattfindet. Es besteht-somit zwischen den Pneumatikkammern auf beiden Seiten des Druckkolbens 82 eine pneumatische Verbindung über die mittleren Ventilräume 113, 114 des 4/2-Wege-Ventils 92.

The operation of the setting tool for blind rivet nuts described above is as follows:

• The drawing Fig. 2a and Fig. 2b shows the setting tool or the valves described with reference to Figs. 3 and 4 (4/2-way valve 92, make-up valve 120) in the ready position, ie when compressed air from the compressed air hose 96 comes from a compressed air source , but when the device is not operated. As already mentioned, the 4/2-way valve 92 operates with negative control; When the operating button 119 'is not actuated, compressed air is available from the compressed air source through the compressed air hose 96 via the connecting bore 101, the first valve chamber 112 delimited by the first receiving ring 109, the throttle opening 108, the cylinder chamber 105, the' bore 104, the annular chamber 103 and the invisible one Bore on valve 119, 119 '. In doing so, it acts in the cylinder space 105 of the 4/2-way valve 92 for the greater application Surface of the control spool 106 and holds it in the position shown in Fig. 3, and the compressed air acts there on the smaller annular surface of the control spool 106. Because of the area ratio of the two opposite surfaces of the control spool 106, this is held in the position shown. In this position, the two valve chambers of the 4/2-way valve 92, which are located at a distance from one another, the valve chamber 115, which is connected to the atmosphere, and the valve chamber 112, which is connected to compressed air, are supported by the sealing effect of the seal carried by the two receiving rings 109, 110 which are at a distance from one another the two sections with the average diameter of the control slide 106 are sealed off from the two valve spaces 113, 114 located between them, while these two adjacent valve spaces, one of which 113 with the pneumatic chamber on the rear side of the pneumatic pressure piston 82 and the other 114 with the Pneumatic chamber 88 located in front of the pressure piston 82 and is also connected to the pneumatic connecting bore 116 in the handle B, also have a connection because the portion of the control slide 106 with the smallest diameter is in the region of the central receiving ring 111, so there is no sealing here . There is thus a pneumatic connection between the pneumatic chambers on both sides of the pressure piston 82 middle valve spaces 113, 114 of the 4/2-way valve 92.

Through the continuation 97 of the compressed air connection bore 93 (FIG. 3), there is also a continuous compressed air connection to the intermediate space 64 between the extension 63 of the device head A and the handle piece B surrounding it. The compressed air can initially still spread from here through the bore 72 in the Housing 1 of the device head A to the annular space 73 between the reset piston 28 and the motor housing 32 (cf. FIG. 2a); here it acts on the rear ring surface (facing the motor housing 32) of the return piston 28 and holds it in contact with the pull piston 15. From here, the compressed air can also pass the hexagon 47 past the inside of the pull piece 4 and penetrate through the central bore of the stopper to act on the locking piston 48 and to hold the compression spring 50 tensioned. From the annular space 73 there is also a compressed air connection through the bores 60, 61 in the motor housing 32 to the annular space 52 to the enlarged annular space 52 'between the motor housing 32 and the valve housing 33 which rotatably surrounds it, where the further connection is seated on its inner valve seat Valve body 55 is interrupted in this unactuated state of the device.

In this state there is also compressed air above the

Fig. 3 visible connection bore 99 directly from the compressed air connection in the space 123 of the valve housing 98 of the make-up valve 120 (see FIG. 4), acts on the surface of the valve body 125 located there and keeps the valve closed on its valve seat formed on the valve cylinder 121.

If the device is now to be operated - although it must of course be assumed that the hydraulic system is completely filled with hydraulic medium - the operator takes the blind rivet nut in his left hand, grips the setting tool on handle B with his right hand and guides the blind rivet nut and mandrel 7 of the setting tool together. To twist the blind rivet nut onto the threaded mandrel 7 with the aid of the compressed air motor 37, 38, the control valve 55 must be actuated, which is done with the aid of the actuating lever 62 which is pivoted on the side of the valve housing 33.

An advantage of the setting tool according to the invention is that the operator does not have to move this actuating lever 62 by hand. The valve housing 33, which is rotatable around the motor housing 32, is brought into the appropriate position so that the actuating lever 62, for example, by lightly pressing against the chest, at the height of which the operator holds the device during this process anyway, or against the lower part arm can be operated. The actuating lever 62 comes into contact with the valve body 55, which protrudes correspondingly from the valve housing 33, lifts it off its inner valve seat and brings it sealingly into contact with its outer valve seat. Thus, a passage for the compressed air from the enlarged annular space 52 'into the valve bore 54, from there through the connecting bore 56 in the valve housing 33 in the annular space 57 and through the connecting bores 58, 59 in the lower bearing flange 36 of the compressed air motor 37, 38 to one of them Entry opening released. The rotor 37 of the compressed air motor 37, 38 is set in clockwise rotation by the inflowing compressed air, and this drives the pulling element 4 to the right via the planetary gear 45 and the hexagon 47, so that the threaded mandrel 7 carried by the pulling element 4 is turned to the right and thus the blind rivet nut can be drilled onto the mandrel 7.

If the blind rivet nut is drilled up to the mouthpiece 2 of the setting tool and lies there, the force of the air motor (drillers) 37, 38 is not so great that the blind rivet nut can be deformed. The compressed air motor 37, 38 is rather stalled and stops. The actuating lever 62 on the valve housing 33 can be released again. Then the mandrel 7 with the blind rivet nut twisted on until the setting head is seated in the drill hole provided in the material to be joined is inserted and the operator actuates the 2/2-way valve 119 by depressing the control button 119 'to negatively actuate the 4/2-way valve 92. In its actuated position, the 2/2-way valve Valve 119 connects between the annular space 103 on the control cylinder 102 of the 4/2-way valve 92 and the atmosphere, so that the compressed air escapes from the cylinder space 105 of the control cylinder 102 and the application of the large contact area of the control slide 106 stops, so that the compressed air which is constantly present at the smaller actuating surface of the control slide 106 in the space 112 can now push the control slide 106 to the left into the control cylinder 102. This results in the middle receiving ring 111 being sealed on the fourth (outer) section of the control slide 106 with the medium diameter, while the two outer sealing rings 109, 110, one 109 in front of the control slide 106, the other 110 in the area of the section reach the smallest diameter of the spool 106, so that no more sealing takes place on them. Thereafter, the two outer valve spaces 112 and 115 are connected to the respectively adjacent valve spaces 113 and 114, while the two middle valve spaces 113 and 114 are tightly separated from one another. Accordingly, the in front of the pneumatic pressure piston 82 receives in the Pneumatic chamber 88 located in cylinder chamber 79 via the valve chambers 114 and 115 communicates with the atmosphere, while compressed air can pass through valve chambers 112 and 113 and via the channel pipe 117 connected to valve chamber 113 in cylinder chamber 79 into the pneumatic chamber on the rear side of pressure piston 82 and thus acts on the pressure piston 82 in the actuating direction (arrow P in FIG. 2b) on its surface F1. The pneumatic pressure piston 82 thus moves together with the immersion piston 83 firmly connected to it in the direction of the arrow P (without however coming into contact with the handle B), the air contained in the pneumatic chamber 88 lying in front of it being able to escape to the atmosphere . The plunger 83 is tightly guided on the free end of the compensating piston 81, which is reinforced by a sleeve 81b in the exemplary embodiment shown. At the same time, the compensating piston 81, which is open at the bottom of the cylinder pot, ensures pressure equalization in the interior space which widens when the plunger 83 moves and is determined by the plunger 83 and the compensating piston 81. The plunger 83 penetrates into the hydraulic space 69 filled with hydraulic medium and displaces the hydraulic medium through the housing bore 74 into the annular space 75 between the fixedly fixed casing ring 19 and the annular pressure surface of the pull piston 15 in the housing 1. The hydraulic medium acts on the pull piston 15 in the pulling direction. This arrives, depending on

Stroke sooner or later, after the start of its movement in abutment against the stop ring 27 fastened behind it on the pull piece 4 and thus takes the pull piece 4, which carries the threaded mandrel 7, in its movement. The restoring piston 28 resting on the pulling piston 15 is also moved by the stroke required for the riveting process against the pneumatic force acting on the restoring piston 28. The compressed air previously introduced into the annular space 73 between the reset piston 28 and the motor housing 32 is thereby displaced. The duct tube 51 fastened in the reset piston 28, which produces a pneumatic connection between the annular space 31 enclosed by the reset piston 28 and a bore in the motor housing 32 leading into the planetary gear 45, can be pushed into this bore accordingly during this pulling movement. In the pulling movement described, the blind rivet nut is deformed as a result of the screw engagement of the threaded mandrel 7, and the setting process is carried out with the formation of a closing head on the side of the material to be joined facing away from the device. With the pulling movement of the pulling piece 4, the annular piston 18 attached to its circumference also reaches the inside of the cylinder sleeve 24 and lies sealingly against the inner surface thereof. When the setting process is complete, the control button 119 'is released and the 2/2-way valve 119 returns to its starting position, so that the cylinder chamber 105 penetrates as described above Compressed air can return control spool 106 to the starting position shown in FIG. 3 against the force acting on its smaller, opposing loading surface. The pneumatic chambers of the cylinder pot 79 lying on both sides of the pneumatic pressure piston 82 are connected to one another again via the two middle valve spaces 113, 114 of the 4/2-way valve 92, and the setting tool begins to return to its starting position or standby position . The arrangement of the compensating piston 83 in the cylinder braid 79 brings the two surface sizes of the ring surfaces F1 'in front and F1 behind the pressure piston 82 to approximately the same values. The compressed air previously introduced into the pneumatic chamber on the back of the pneumatic pressure piston 82 now also reaches the front pneumatic chamber 88 and from there via the bore 116 in the handle B, which continues in the housing 1 of the device head A, and by a puncture in the Cylinder sleeve 24 in the sealed space created during the pulling movement between the shoulder 25 of the cylinder sleeve 24 and the annular piston 18. By pressurizing both the annular piston 18 on its annular surface F4 and the reset piston 28 on its annular surface F3 'with compressed air in the same direction, a special area ratio is created which enables the reset piston 28 to pull the pull piston 15 together with the pulling element 4 and the threaded mandrel 7 into the outlet position to move back. The hydraulic medium located in the annular space 75 of the device head A is therefore pushed back into the hydraulic space 69, as a result of which the plunger 83, by acting on its surface F2, and thus also the pneumatic pressure piston 82 are pushed back into their starting position. Air displaced from the plunger can escape through the interior of the open compensating piston 81.

The compressed air of the previous riveting process is in the switching position described above, in which the two pneumatic chambers in front of and behind the pressure piston 82 and the space created between the shoulder 25 of the cylinder sleeve 24 and the ring piston 18 are connected at the same time on the two ring surfaces F1 'and F1 of the pressure piston 82 and the annular surface F4 of the annular piston 18. When the device is connected to compressed air via the bore 97 (FIG. 3), the intermediate space 64 and the bore 72 (FIG. 2a), compressed air is always present on the return piston 34 with its annular surface F3 ', while on the other hand against the annular surface F3 of the tension piston 15 the hydraulic medium acts in the opposite direction.

beaufschlagt. Da diese Kraft größer ist als die ihr entgegenwirkende Kraft aus

werden der Tauchkolben 83 mit dem Druckkolben 82 in Richtung Zylindertopfboden und das Zugstück 4 mit dem Gewindedorn 7 in Richtung Mundstück 2 bzw. aus ihm heraus bewegt, so daß trotz der im Gerät verbliebenen Druckluft des vorangegangenen Setzvorgangs ein Rücklauf des Kolbensystems in seine Ausgangsstellung erfolgt. Es gilt daher:

The force from (F3 'of the return piston and F4 of the ring piston) x pressure now acts in the direction of the mouthpiece 2 on the amount of oil in the hydraulic chamber 75 between the tension piston 15 and the casing ring 19 and pushes it back into the hydraulic chamber 69. In this case, the plunger 83 is released by the force via its piston surface F2 directed against the hydraulic medium

acted upon. Because this force is greater than the counteracting force

the plunger 83 with the pressure piston 82 in the direction of the cylinder head base and the pulling piece 4 with the threaded mandrel 7 in the direction of the mouthpiece 2 or out of it, so that despite the compressed air remaining in the device of the previous setting process, the piston system returns to its starting position. The following therefore applies:

Return force in the starting position.

For the working stroke, however, the following applies:

As long as the ring piston 18 moves sealingly within the cylinder sleeve 24 during the resetting of the pulling device 4, 15, the previously introduced compressed air is present on it. Towards the end of the return movement, the annular piston 18 leaves the cylinder sleeve 24. The stored compressed air now flows around the annular piston 18, enters the annular space 20 surrounding it outside the cylinder sleeve 24 and also the end of the tubular extension 16 of the pulling piston 15, from there through the fit space 14 between the pulling piece 4 and the pulling piston 15 with extension 16 further into the annular space 31 surrounded by the return piston 28 and further through the sewer pipe 51 into the interior of the motor housing 32 and finally through the planetary gear 45 and a bore (not shown in the drawing) in the planetary gear 45 adjacent bearing flange 36 to the other inlet opening of the compressed air motor 37, 38. The compressed air entering the compressed air motor 37, 38 drives the rotor 37 thereof to the left. The compressed air that is present is sufficient to make a few left turns of the rotor 37 and thus of the tension member 4 together with the mandrel 7, that is to say the mandrel 7 by a few. Unscrew the rotations from the blind rivet nut. However, it is not sufficient to always ensure safe, complete drilling; because the number of rotations depends on the volume of the air previously stored in the pneumatic cylinder 79.

To ensure that the drilling process can be carried out reliably after each setting process, the make-up valve 120 already described above with reference to FIG. 4 is provided in the flange part of the handle B connected to the cylinder pot 79.

As already explained, the pressure prevailing in the pneumatic chamber 88 located in front of the pneumatic pressure piston 82 lies on the larger pressure surface F6 of the valve body 125, while its smaller pressure surface F5 lies in the space 123 between the make-up valve 120 and the bottom of its valve housing 98 is constantly acted upon by compressed air from the compressed air source through the connecting bore 99. As long as the pneumatic chamber 88 is depressurized, the valve body 125 is accordingly held in its seat on the valve cylinder 121. If, after the riveting process has been completed, as a result of the reversal of the 4/2-way valve 92, the two pneumatic chambers located in front of and behind the pressure piston 82 are connected to one another, the compressed air previously introduced to actuate the device reaches the rear of the pressure piston 82 , for example. 6 bar, also in the pneumatic chamber 88 lying in front of it and here now also acts on the valve body 125 on its larger contact surface F6. Because of of the area ratio of the two acting surfaces F5: F6, the compressed air entering the pneumatic chamber 88 can move the valve body 125 against the force acting from the compressed air connection on the smaller acting surface F5 in its valve cylinder 121 and lift it off its valve seat. Now the compressed air from the compressed air source in the space 123 can pass through the open make-up valve 120 into its annular space 126 and through the connecting bores 124 in the valve cylinder 121 into the annular space 122 on its outer surface and from there has a connection again via the housing bore 116, the annular space 20 in Housing 1, the fitting space 14, the annular space 31 in the return piston 28, the sewer pipe 51, the planetary gear 45 and the bearing flange 36 for the inlet opening of the compressed air motor 37, 38 for left-hand drive. Thus, via the make-up valve 120, the compressed air required for the complete and safe removal of the threaded mandrel 7 by the blind rivet nut is provided from the compressed air connection, that is to say from the compressed air source.

The twisting movement is ended by a pressure reduction in the pneumatic chamber 88 lying in front of the pressure piston 82, consequently the valve body 125 of the make-up valve 120 gradually or decelerates back to its seat due to the compressed air acting on its smaller acting area F5 is pressed. The degree of deceleration is determined by the degree of the previous opening, which can be varied by the adjusting screw 127.

Another embodiment of the setting tool according to the invention is shown in FIGS. 5 and 6, in which the actuating member for the control valve is arranged in a region near the actuating member for the setting tool.

Fig. 5 shows a longitudinal section through the tool head A and part of the handle B of this embodiment of the setting tool according to the invention as shown in Fig. 2a (and on the same scale as this). The same parts as in Fig. 2a are given the same reference numerals in Fig. 5, so that to avoid repetition of these parts reference can be made to the description of Fig. 2a.

FIG. 6 shows, on an enlarged scale compared to FIG. 5, a cross section through the setting tool according to the invention in the area of the hand protection 128 along the line EF in FIG. 5, viewed in the direction of the arrow. The representation is kept in relation to a practical embodiment on a scale of 2: 1. 6 shows at the same time a longitudinal section through the actuating element 62 'for the control valve, and there are also indicated the housing 1 of the device head A, the adapter 5 and the sleeve 3, which lie behind the actuating member 62 '.

5 and 6, the actuator 62 'for the control valve in the hand guard 128 is arranged near the device head A. It can thus comfortably by the operator, who holds this on the handle B with his hand when working with the setting tool and for initiating the riveting process, depresses the control button 119 "with a finger of the hand, usually with the index finger, also preferably by same finger operated.

As can be seen from FIGS. 5 and 6, the actuating element 62 'is accommodated in a horizontal bore 129 (with a circular setting cross-section through the hand guard 128 when the setting tool is parked on a contact surface), namely in the end part of the hand guard 128 towards the tool head A before it goes into a ring shape merges, which encompasses the device head A at its front end. As seen from its two openings, a compression spring (coil spring) 130 is inserted into the center of the bore 129. Two cylindrical sleeves 62 'serve as the actuating member, each of which already performs the actuating function for itself and which can be actuated selectively, for example by a right-hander who holds the setting tool in the right hand, with the index finger of the right hand, from a left hand holding the setting tool in the left hand with the index finger of the left hand. 6 from the left or from the right in each case in one of the openings of the bore 129, in such a way that a space remains between the inner ends in the bore 129 and that the outer ends thereof protrude a certain amount from the hole. The sleeves 62 'each have, at a distance from their inner end, a collar 131, the outer diameter of which is somewhat smaller than the inner diameter of the bore 129. The compression spring 130 rests on the collars 131. From the collars 131, the inner ends of the sleeves 62 'still protrude to a certain extent (from a few spring windings) into the space surrounded by the compression spring 130, that is to say into the compression spring 130. Outside the region of the collars 131, the outer diameter of the sleeves 62 'is smaller than the inner diameter of the bore 129 to such an extent that between the bore 129 and the sleeves 62', in the exemplary embodiment, hollow rivet-shaped receiving sleeves 132 are press-fitted into the bore 129, which the Hold the sleeves 62 'in position in the bore 129 in such a way that the sleeves 62' are held in the receiving sleeves 132 so tightly that they can each be pressed against their outer end by means of a finger, preferably the index finger, which is also the control button 119 'actuated, bring the compression spring 130 into the block position, overcoming its spring force. Consequently Both sleeves 62 'each protrude from the associated receiving sleeve 132 by at least the amount required to bring the compression spring 130 out of its (relaxed) starting position into a block position by means of one of the sleeves 62'.

In the area of the compression spring 130, FIG. 6 also shows the opening 133 of the bore 134 shown in FIG. 5 in the hand guard 128, which bore 134 opens into the compression spring 130 approximately in the central region of the bore 129.

In Fig. 5, the essentially hollow cylindrical valve housing 33 '(in contrast to the embodiment according to Fig. 2a not rotatable) is fixed between the housing 1 of the device head A and the muffler 40' and thus simultaneously has the function of a further housing part of the device head A. Within the Valve housing 33 'is coaxially arranged with an essentially hollow cylindrical valve body 55' of the control valve as a slide, and within valve body 55 'coaxially with it the motor housing 32 at least partially surrounded by valve body 55'. Between the outer wall of the motor housing 32 and the inner wall of the valve body 55 'remains a small annular space as a clearance 135, which is sealed off from the outside by O-rings 136 and 137. Between the outer wall of the valve body 55 'and the A small annular space 138 is likewise formed on the inner wall of the valve housing 33 ', which is closed off by a rear 0-ring 139 and in the approximately central region of which the outer wall of the valve body 55' is sealed against the inner wall of the valve housing by a further 0-ring 140. In the region of the front stop of the valve body 55 ', the annular space 138 is conically widened outward on an extension of the motor housing 32 to be described, up to a bore in the front end of the valve housing 33'; In this hole and in a further hole or a lateral slot in the housing 1 of the device head A, a tube 141 is embedded, which extends through a hole in the housing 1 at the front end of the ring-shaped part of the hand protection 128 into this ring-shaped part and there opens into a circumferential groove 142 which runs approximately at the height of the bore 129 in the hand guard 128 in the inner wall of the annular part and which is sealed inwards against the front end of the housing 1 by means of an O-ring 143, but which is directed outwards the groove 142 does not completely fill out, so that in the groove 142, for example, if it approximates the cross section of a partial oval, for example a circumferential free space 144 with a cross section of approximately quarter moon can be formed, which has connection 128 with the bore 134, in the hand guard which bore 134, as already described, in turn in bore 129 for Recording the actuators 62 '(see. Fig. 6) opens.

5, the valve body 55 'in front of the (approximately middle) 0-ring 140 has a fine bore (puncture) 145, through which, as will be explained in more detail, compressed air from the fit clearance 135 between the motor housing 32 and the valve body 55' is always present. into the annular space 138 between the valve body 55 'and the valve housing 33' and from there through the tube 141, the free space 144 in the groove 142 and the bore 134 in the area of the compression spring 130 into the bore 129, from where the compressed air passes through the sleeves 62 ', when these are in the unactuated state, flows outwards.

FIG. 5 shows this embodiment of the setting tool according to the invention in the ready position (as in FIG. 2a the embodiment there). The air in the annular space 73 passes through the bores 61, 60 'into an outer groove 146 of the motor housing 32 and into the clearance 135 between the motor housing 32 and the valve body 55' and through the fine bore 145 in the valve body 55 'in the (here through the 0-ring 140 sealed to the rear) annulus 138 between valve body 55 'and valve housing 33', further through the tube 141, the free space 144 in the groove 142 located in the annular part of the hand guard 128 and the bore 134 in the hand guard 128 in the bore 129 for receiving the actuators 62 ', from where they are in the the unactuated state of the setting tool constantly flows to the outside.

Behind the (approximately middle) 0-ring 140, which is held in a circumferential outer groove of the valve body 55 ', there is an outer step 147 of the valve body 55'; From this step 147 to the rear end, the valve body 55 'has an outer diameter which is reduced compared to the outer diameter of the part of the valve body 55' which lies in front of the outer step 147. Immediately behind this outer step 147 there is another bore (puncture) 148 through the valve body 55 '. The (part of) the annular space 138 between the valve body 55 'and the valve housing 33' located behind the (approximately middle) 0-ring 140 is sealed to the rear by the 0-ring 137. Compressed air thus passes through the second bore 148 in the valve body 55 'from the clearance 135 between the motor housing 32 and the valve body 55' into the (part of the) annular space (s) 138 located behind the (approximately middle) 0-ring 140 between the valve body 55 ' and valve housing 33 'and there acts on the valve body 55' on its outer step 47 and holds it in its switching position according to the drawing in FIG. 5 (ready position).

If one of the two actuating members 62 'is now actuated by finger pressure, that is to say from the bore 129 in the hand guard 128 protruding end of the actuator 62 'while overcoming the force of the compression spring 130 in the bore 129 in the hand guard 128 pressed into the bore 129, the compression spring 130 is brought into the block position after the actuator 62' has traveled a relatively short distance , wherein the windings of the compression spring 130 abut each other in such a way that compressed air can no longer get into the interior of the compression spring 130 from the opening 133 of the bore 134 in the hand guard 128, as a result of which the above-described constant outflow of compressed air through the actuating member 62 'is prevented. As a result, compressed air builds up in the bore 134, the free space 144, the tube 141 and the part of the annular space 138 located in front of the (approximately middle) 0-ring 140, which now also intensifies between the front (annular) surface Fa of the valve body 55 'and the rear (ring) surface Fb of the annular disk-shaped extension 149 formed as a front stop for the valve body (slide) 55' penetrates in the front end region of the motor housing 32. Since the front surface Fa of the valve body 55 'is larger than the (ring) surface Fc of the outer step 147 of the valve body 55' behind the (approximately middle) 0-ring 140, the compressed air builds up on the front surface Fa of the valve body 55 'a switching of the valve body 55' against the smaller force of the compressed air present on the smaller area Fc of the outer step 147 such that the valve body (slide) 55 'to its rear stop on the silencer 40'. Before this switching position of the valve body 55 'is reached, the rear 137 of the two 0-rings 136 and 137 which seal the clearance 135 between the motor housing 32 and the valve body 55' has a plurality of bores 150 provided in the rear region of the motor housing 32 (in the exemplary embodiment shown in FIG. 5) there are eight holes 150) distributed over the circumference of the motor housing, so that there is now a connection from the annular space 73 via the holes 61, 60 'and the outer groove 146 to the clearance 135 and from there through the plurality of holes 150, a transverse hole 58' , the blind bore 59 and the first of the two inlet openings to the rotor 37 of the compressed air motor 37, 38 and thus compressed air from the clearance 135 between the motor housing 32 and valve body 55 'through the plurality of holes 150 in the motor housing 32 and the short transverse bore 58' (in the motor housing 32 and bearing flange 36) in the blind bore 59 in the front bearing flange 36, the connection with the first n of the two inlet openings of the compressed air motor 37, 38, so that the rotor 37 of the compressed air motor 37, 38 is set in clockwise rotation by the inflowing compressed air, thus starting the drilling process for the drilling of the blind rivet nut onto the mandrel 7.

If the twisting-on process (as in the exemplary embodiment according to FIGS. 2a and b) has ended, the actuating member 62 'in the hand guard 128 can be released again, so that the compression spring 130 in the bore 129 in the hand guard 128 is relieved and compressed air is continuously released from the actuating member 62 'can flow off. At the same time, the valve body 55 'returns to its initial position (ready position) shown in FIG. 5.

This is followed by the insertion of the threaded mandrel with the blind rivet nut twisted into the borehole provided in the material to be joined and the initiation of the riveting process by actuating the operating button 119 'of the setting tool. These and all other processes, including the drilling off of the blind rivet nut, are carried out in the manner described for the exemplary embodiment in FIGS. 2a and b, the structural design of the modified embodiment described here corresponding to the exemplary embodiment of the setting tool according to the invention described there. It was therefore also possible to dispense with the fact that the further part of the handle B not shown in FIG. 5 and the pneumatic part C according to FIG. 2b are shown separately in the drawing. The same applies to the parts described above for FIGS. 3 and 4.

As from the description of both embodiments of the Setting tool for blind rivet nuts according to the invention can be seen, only two actuating elements 62 or 62 'and 119' have to be actuated on the setting device for screwing the blind rivet nuts onto the threaded mandrel, for the actual riveting process and for unraveling the blind rivet nut. The riveting process is initiated by the actuation of the actuating member for the control valve, and the riveting process is carried out by depressing the operating button 119 '. After the riveting process has been completed, the mandrel is automatically drilled out, in some cases in an energy-saving manner with the compressed air introduced and stored in the device for the riveting process, in part via the make-up valve according to the invention with compressed air from the connected compressed air source, in order to ensure complete unraveling, and that too Make-up valve is automatically actuated by the previously stored compressed air after the riveting process. By the actuating member for the control valve and thus for the twisting operation according to one embodiment as a lever being articulated laterally on a valve housing 33 which can be rotated around the device head A, after the valve housing 33 has been brought into the correct position, it can be pressed, for example by lightly pressing against it the chest are operated, and there are no frictional movements against the wall as in known devices for drilling. After the other In one embodiment, the actuating member for the control valve and the twisting process is arranged in the hand guard 128, and thus still in the area of the operator's finger, which also initiates the riveting process by depressing the operating button 119 '. The setting tool can thus be held continuously in the hand at work; it does not have to be put out of hand for the up and down drilling process in order to be able to initiate the drilling process, since there is no need to operate the drilling device by hand. The actuations of the control elements for the drilling and riveting processes follow one another in the work cycle, and the operator has his other hand free to insert the mandrel with the blind rivet nut in the drill hole provided in the material to be joined. This enables rapid, undisturbed working with the setting tool according to the invention, which results in considerable time savings when setting blind rivet nuts. The operator can concentrate entirely on the actual point of their work, the connection points of the material to be joined, and their attention is not called upon by various manipulations which are necessary on the riveting device and which require an alternating gripping and setting down of the device.

As safe by the make-up valve according to the invention is that the compressed air motor 37, 38 is always supplied with sufficient compressed air for the drilling process, blind rivet nuts can be processed over the wide range of all common sizes - e.g. from M3 to M12 - and in all common materials such as aluminum alloys, steel, stainless steel, brass, etc. will.

With reference again to Fig. 2a it should be mentioned that the distance L of the undercut 2 'behind the front part of the mouthpiece 2 to the lock nut 6 is adjustable, and this adjustable distance L is the tool stroke (the drag length) for the riveting process. The distance L corresponds to the maximum device stroke in the exemplary embodiment shown in FIG. 2a. The setting is made by turning the mouthpiece 2. If the mouthpiece 2 is brought into contact with the counter nut 6 by turning it to the right with its undercut 2 ', the distance L and thus the device stroke are zero (zero position). On the way to this position, the mouthpiece 2 moves over the thrust washer 10, the bearing balls 9 and the pressure ring 11, the pull piece 4 and thus the stop ring 27 backwards, ie in the direction of the compressed air motor 37, 38. From the zero position, in turn, by turning the left Mouthpiece 2, the distance L can be set to the desired dimension, up to the maximum device stroke, thrust washer 10, bearing balls 9, thrust ring 11, pull piece 4 and stop ring 27 in opposite directions Move direction. The annular space 31 offers the necessary space for the forward and backward movement of the stop ring 27.

Claims (34)

1. Pneumatic-hydraulic setting device for blind rivet nuts consisting of a pneumatic-hydraulic translation system and a pneumatically and hydraulically connected device head, in which a pulling device, which carries a mandrel protruding from the mouthpiece of the device head, for processing (setting) one on the mandrel screwed-on blind rivet nut can be moved axially against a restoring force, the part of the pulling device carrying the threaded mandrel for the screwing on and off of the blind rivet nut being driven by a compressed air motor accommodated in the device head, the compressed air before the actual riveting process for untwisting the blind rivet nut and after the riveting process compressed air for The blind rivet nut can be drilled off, as well as a valve arrangement, characterized in that the valve arrangement (92) is assigned a control valve (55) which is connected to the compressed air motor (37, 38) and that after the riveting process has taken place ch relief of the actuating member (119 ') of the compressed air motor (37, 38) can be connected to the pneumatic chambers (88) of the pneumatic part (C) of the translation system. 2. Setting tool according to claim 1, characterized in that the control valve (55) is switched on in a pneumatic connection (64, 72, 73, 61, 60, 52, 56, 57, 58, 59) between the compressed air source and the compressed air motor (37, 38). 3. Setting tool according to claim 1 or 2, characterized in that the control valve (55) can be actuated by pressure. 4. Setting tool according to one of claims 1 to 3, characterized in that the valve body (55) in the rest or shut-off position protrudes to a certain extent from the housing (33) of the control valve (55). 5. Setting tool according to claim 4, characterized in that laterally on the valve housing (33) an actuating lever (62) extending over the control valve (55) is pivotably articulated, which, when lightly pressed on its free end, is connected to the valve housing (33 ) protrudes valve body (55), whereby the control valve (55) can be actuated. 6. Setting tool according to one of claims 1 to 5, characterized in that the control valve (55) is arranged in a around the housing (32) of the compressed air motor (37, 38) rotatable valve housing (33). 7. Setting tool according to one of claims 1 to 6, characterized characterized in that the actuation of the control valve (55) switched on in the pneumatic connecting line (64, 72, 73, 61, 60, 52, 56, 57, 58, 59) between a first inlet opening of the compressed air motor (37, 38) and the compressed air source ) the compressed air motor (37, 38) can be supplied with compressed air for rotation in one direction of rotation before the actual riveting process and that the compressed air introduced and stored for the riveting process itself into the pneumatic-hydraulic translation system (C, B) after the riveting process has been completed during and / or after resetting the pulling device (4, 15, 27) the compressed air motor (37, 38) can be fed through a second inlet opening for rotation in the other direction of rotation. 8. Setting tool according to one of claims 1 to 7, characterized in that the control valve (55) is a 3/2-way valve. 9. Setting tool according to one of claims 1 to 8, characterized in that between the outer wall of the motor housing (32) and the inner wall of the valve housing (33) rotatable about the same, a bilaterally sealed annular space (52, 52 '), which consists of a pneumatic Connection (60, 61, 73, 72, 70, 64, 97, 93) is permanently connected to the compressed air source and in which the wall of the valve housing (33) penetrating bore (54) opens into which the valve body of the control valve (55) is slidably arranged, and that from this bore (54) a connecting bore (56) to another, sealed on both sides annular space (57) between the outer surface of the motor housing (32 ) and the inner surface of the valve housing (33) and from there connecting bores (58, 59) in the motor housing (32) and in the one bearing flange (36) of the compressed air motor (37, 38) lead to its first inlet opening. - 10. Setting tool according to claim 9, characterized in that both the inner edge and the outer edge of the wall of the valve housing (33) penetrating bore (54) are designed as a valve seat for the valve body of the control valve (55) and this on the inner, in Annular space (52, 52 ') located valve seat interrupts the connection between the first inlet opening of the compressed air motor (37, 38) and the compressed air source in its unactuated position and establishes it in its actuated position and on the outer valve seat the connection between the first inlet opening of the compressed air motor (37 , 38) and the atmosphere in its unactuated position and interrupts in its actuated position. 11. Setting tool according to one of claims 3 to 10, characterized in that the annular space (52) between the motor housing (32) and valve housing (33) in the region of the valve body of the control valve (55) receiving bore (54) through an annular groove in the The inner surface of the valve housing (33) and / or in the outer surface of the motor housing (32) is expanded (52 '). 12. Setting tool according to one of claims 1 to 3, characterized in that the control valve (55 ') can be actuated by compressed air. 13. Setting tool according to claim 12, characterized in that the control valve is integrated in the tool head (A) and consists of a valve housing (33 ') with a valve body (55') arranged coaxially movable therein. 14. Setting tool according to claim 12 or 13, characterized in that the valve body (55 ') of the control valve by means of a in the region of or near (128) the actuating member (s) (119') arranged for the initiation of the riveting process of the setting device ( 62 ') can be actuated. 15. Setting tool according to one of claims 12 to 14, characterized in that the valve body (55 ') by connecting compressed air by means of its loading actuating member (62 ') can be actuated. 16. Setting tool according to one of claims 12 to 15, characterized in that the actuating member for the control valve (55 ') is arranged in a bore (129) in, on or near the tool head (A) of the setting tool and that means (62' , 130) are provided, by means of which a compressed air flow can be prevented. 17. Setting tool according to claim 16, characterized in that the actuating member consists of at least one sleeve (62 '), by means of which a compression spring (130) can be brought into the block position by finger pressure and the compressed air flow can thus be prevented. 18. Setting tool according to one of claims 12 to 17, characterized by a pneumatic connection (129, 133, 134, 144, 141, 138, 145, 135) from the actuating member (62 ') to the valve body (55') of the control valve and from this (through 150, 58 ', 59) to an inlet opening to the rotor (37) of the compressed air motor (37, 38). 19. Setting tool according to claim 18, characterized in that the pneumatic connection between the actuating member (62 ') of the control valve (55') and the one inlet opening to the rotor (37) of the compressed air motor (37, 38) in turn pneumatic Ver binding (135, 146, 60 ', 61, 73, 72, 64) to the compressed air source. 20. Setting tool according to one of claims 12 to 19, characterized in that the valve body (55 ') of the control valve by means of compressed air in the starting position (standby position) is stable. 21. Setting tool according to claim 20, characterized in that between the valve body (55 ') and valve housing (33') there is an annular space (138) closed at its rear end, that the valve body (55 ') in this annular space (138) approximately in its central region is sealed (140) against the valve housing (33 ') and has an external step (147) behind this seal (140) and that compressed air from the pneumatic connection (135, 146 , 60 ', 61, 73, 72, 64) can be introduced to the compressed air source. 22. Setting tool according to one of claims 12 to 21, characterized in that when compressed air is switched on, by means of the actuating member (62 ') of the control valve, the valve body (55') as a result of the area ratio between the front face (Fa) and the smaller area ( Fc) the outer step (147) of the valve body (55 ') in its switching position to initiate the untwisting Blind rivet nut is movable. 23. Setting tool according to one of claims 6 to 22, characterized in that from the second inlet opening of the compressed air motor (37, 38) there is a pneumatic connection (51, 31, 14, 20, 116) to the one connection of the valve arrangement (92) , by its actuation for the actual riveting process compressed air can be introduced into the pneumatic chamber located on the back of the pneumatic pressure piston (82) of the pneumatic-hydraulic translation system (C, B), and that the valve arrangement (92) in its initial position Pneumatic chamber located on the back of the pneumatic pressure piston (82) connects to the pneumatic connecting line (51, 31, 14, 20, 116) to the second inlet opening of the compressed air motor (37, 38) and separates it from it in the actuated state. 24. Setting tool according to claim 23, characterized in that the pneumatic connection between the second inlet opening of the compressed air motor (37, 38) to the one connection of the valve arrangement (92) through a longitudinal bore (51) in the motor housing (32), behind the pulling device (4, 15) for the threaded mandrel (7) lying housing space (31), through the pulling device (4, 15) into a surrounding housing ring sealed in both longitudinal directions space (20) of the device head (A) and from there through a hole (116) in the housing of the pneumatic-hydraulic translation system (B, C). 25. Setting tool according to claim 24, characterized in that the pulling device (4, 15) is constructed in several parts and essentially consists of a hollow pulling piece (4), in one end of which the threaded mandrel projecting from the mouthpiece (2) of the tool head (A) (7) is screwed in and in the other end engages a shaft (47) which can be driven by the compressed air motor (37, 38), and from a pulling piston (4) which surrounds this pull piece (4) while leaving a fit space (14) and can be moved tightly on the housing wall (15), wherein the pull piece (4) carries a stop (27) in front of the pull piston (15) in the pulling direction and the pull piston (15) can rest on a stop (19) in the opposite direction and the fit space (14) has a part represents the pneumatic connection between the second inlet opening of the compressed air motor (37, 38) and the valve arrangement (92). 26. Setting tool according to claim 25, characterized in that the pulling piston (15) opposite to the pulling direction a pull piece (4) also the fit space (14) maintaining tubular extension Set (16) against which the hydraulic chamber (75) containing the hydraulic pressure surface of the tension piston (15) is sealed by a (rod) seal arranged in the stop (casing ring 19), the connecting bore (74) being separated from the hydraulic chamber (69 ) of the pneumatic-hydraulic translation system (C, B) into the hydraulic chamber (75) and the connecting bore (116) leading to the valve arrangement (92) opens into the housing ring space (20) located on the other side of the stop (casing ring) (19). 27. Setting tool according to claim 25 or 26, characterized in that in the pulling direction in front of the pulling piston (15) a pressurized with the compressed air, annular reset piston (28) against the housing wall and pull piece (4) is arranged tightly displaceable and one surrounded by this , to the traction piston (15) and thus to the fit space (14) open annular space (31) through a through the pneumatic chamber (73) between the return piston (28) and motor housing (32) channel tube (51) with a to the second inlet opening of the compressed air motor (37, 38) leading connection hole in the motor housing (32) is connected. 28. Setting tool according to one of claims 1 to 27, characterized in that between the second entry opening of the compressed air motor (37, 38) and the compressed air source, there is a pneumatic connection (51, 31, 14, 20, 116, 99) into which a riveting process which is closed in the rest position and after the riveting process has been completed by the riveting process in the pneumatic-hydraulic Translation system (C, B) initiated and stored compressed air actuated make-up valve (120) can be switched on. 29. Setting tool according to claim 28, characterized in that the make-up valve (120) has a valve body (125) designed as a differential piston, the smaller application area (F5) of which in a valve chamber (123) permanently connected to the compressed air source at the bottom of the valve housing (98). lies and whose larger application area (F6) lies in a space (88) which can be connected to the pneumatic chamber of the pneumatic-hydraulic transmission system (B, C) on the back of the pneumatic pressure piston (82) after the riveting process has been completed. 30. Setting tool according to claim 29, characterized in that the larger application area (F6) of the valve body (125) lies in the pneumatic chamber (88) lying in front of the pneumatic pressure piston (82). 31. Setting tool according to claim 29 or 30, characterized shows that the actuation stroke of the valve body (125) can be adjusted by an externally accessible adjusting screw (127) on the bottom of the valve housing (98) or the valve chamber (123). 32. Setting tool according to one of claims 29 to 30, characterized in that the valve body (125) is displaceable in a stepped valve cylinder (121) and that when the valve body (125) is raised with the valve chamber (123) on the housing base, i.e. annular space (126) connected to compressed air through bores (124) in the valve cylinder (121) is connected to an annular space (122) in the lateral surface of the valve cylinder (121), which in turn is connected to a pneumatic connecting bore (116). 33. Setting tool according to one of claims 28 to 32, characterized in that the make-up valve (120) is a 2/2-way valve. 34. Setting tool according to one of claims 1 to 33, characterized in that the valve arrangement (92) is a 4/2-way valve.

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