Blind Rivet Fastener Placement Device

Abstract

The invention relates to a blind rivet fixing element placement device (1) having a housing (2), a feed spindle (4) and a drive motor (3) which is connected to the feed spindle (4) via a transmission device (11 - 15), wherein the transmission device (11 - 15) has a driven spindle nut (11) which is in engagement with the thread on the feed spindle (4). It is desired to be able to use such a blind rivet fixing element placement device in a simple manner, not only for placing blind rivets but also for placing blind rivet nuts. For this purpose, it is provided that the transmission device (11 - 15) has a switching coupling (18) which torsionally connects the feed spindle (4) to the housing (2) in a first switching position and torsionally connects the spindle nut (11) to the feed spindle (4) to each other in a second switching position.

Description

Field of the Invention

[0001] The present invention relates to a blind rivet fastener placement device having a housing, a feed spindle, and a drive motor that is connected to the feed spindle via a transmission device, wherein the transmission device has a driven spindle nut that engages with a thread on the feed spindle. Background Art

[0002] A blind rivet fastener is a joining element that is inserted from one side into a hole formed in a workpiece or a stack of workpieces until its placement head abuts against a free surface. When the feed spindle is then actuated, it pulls at the rivet mandrel or the feed mandrel, so that the end of the blind rivet fastener arranged on the other side of the workpiece or the stack of workpieces is immersed and a closing head is formed, so that the blind rivet fastener remains in the workpiece or the stack of workpieces.

[0003] The blind rivet fastener can be configured as a blind rivet or a blind rivet nut. In the case of a blind rivet, the formation of the closing head is achieved by the rivet mandrel, which is pulled by the feed spindle. In the case of a blind rivet nut, the formation of the closing head is achieved by the feed mandrel, which is screwed into the internal thread of the blind rivet nut.

[0004] When a blind rivet is to be placed, it is sufficient for the placement device to be able to grasp the rivet mandrel in order to apply the required pulling force. When a blind rivet nut is to be placed, it is necessary to first screw the feed mandrel provided with an external thread into the blind rivet nut. For this, a rotational movement of the threaded feed mandrel, which is also referred to as the "spindle", is required.

[0005] The screwing of the feed mandrel into the blind rivet nut can be done by hand. However, this is relatively cumbersome and time-consuming. For this reason, it is known that blind rivet fastener placement devices are also used for the spindle.

[0006] When placing a blind rivet, the rivet mandrel detaches or even pulls out of the placed blind rivet. This rivet mandrel must then be removed and disposed of. For this reason, it is advantageous for the feed spindle to have a through-channel or at least one receiving space into which the detached or pulled-out rivet mandrel can enter. This is not necessary in the case of placing a blind rivet nut.

[0007] The different requirements make it difficult to configure a blind rivet fastener placement device such that it can place both blind rivets and blind rivet nuts. Summary of the Invention

[0008] The present invention is based on the task of configuring a blind rivet fastener placement device such that it is suitable for placing both blind rivets and blind rivet nuts with less effort.

[0009] This task is solved in the case of a blind rivet fixing device of the type mentioned at the beginning in that the drive has a switching coupling which, in a first switching position, torsionally connects the feed spindle to the housing and, in a second switching position, torsionally connects the spindle nut and the feed spindle to one another.

[0010] With such a fixing device, blind rivets can be fixed in a simple manner. For this, the switching coupling must be brought into the first switching position. The feed spindle is then torsionally connected to the housing. When the spindle nut is rotated by the drive motor, this rotation causes an axial movement of the feed spindle, which cannot rotate due to its torsional connection to the housing. In the same way, blind rivet nuts are also fixed. However, the drive motor can previously be used to screw the feed mandrel into the blind rivet nut. For this, the switching coupling must only be brought into the second switching position. When the spindle nut and the feed spindle are torsionally connected to one another, the rotation of the spindle nut caused by the drive motor then also causes a corresponding rotation of the feed spindle and thus of the feed mandrel, so that the feed mandrel can be screwed into the blind rivet nut. If necessary, when wanting to transition from fixing blind rivets to fixing blind rivet nuts or vice versa, the feed mechanism acting on the blind rivets or blind rivet nuts must be replaced.

[0011] Preferably, the switching coupling has a switching bush which can be axially displaced on the feed spindle. The switching bush then, depending on its position, axially either torsionally connects the feed spindle to the housing or torsionally connects the spindle nut and the feed spindle to one another.

[0012] In a preferred design, the switching bush is torsionally connected to the feed spindle. Thus, in each switching position only one further connection has to be established.

[0013] Preferably, the switching coupling generates a force fit and / or a form fit between the switching bush and the spindle nut and / or the housing. The switching coupling thus either generates a force fit between the switching bush and the housing in the first switching position and a force fit between the switching bush and the spindle nut in the second switching position, or it generates a form fit instead of the force fit or two form fits instead of the two force fits accordingly.

[0014] Preferably, the switching bush has a first engagement geometry which can engage with a second engagement geometry at the housing. The two engagement geometries form a form fit when they engage with one another.

[0015] It is also advantageous that the switching bush has a third engagement geometry which can engage with a fourth engagement geometry at the spindle nut. Again, the third engagement geometry and the fourth engagement geometry then generate a form fit.

[0016] Preferably, at least one of the engaging geometries is arranged at such a radial distance from the rotational axis of the feed spindle that corresponds to the radius of the switching bush. The engaging geometries are thus arranged radially relatively far outwards. As a result, a larger lever arm is obtained, so that a larger torque can be transmitted. The engaging geometries do not have to correspond exactly to the radial distance from the rotational axis of the feed spindle here. A deviation of ±25% is permitted here.

[0017] Preferably, the housing has a mating support which is torsionally connected to the feed spindle in the first switching position. The housing can then be constructed relatively simply. The mating support forms a rotational stop.

[0018] Preferably, the mating support has a bearing assembly in which the feed spindle is rotatably supported. The mating support can be axially fixed on the spindle, for example, and is arranged axially displaceably in the housing.

[0019] Preferably, the feed spindle has a through longitudinal channel. Through the longitudinal channel, the shed or pulled-out rivet mandrel can then be removed after the blind rivet has been placed.

[0020] Preferably, the channel has an inner contour that is different from a circular shape at least in sections adjacent to its ends. This particularly relates to the ends of the channel which are adjacent to the nozzle through which the rivet mandrel is guided in the case of a blind rivet or the feed mandrel is guided in the case of a blind rivet nut. The inner contour can be constructed polygonally, for example. The inner contour can then be used for torque transmission.

[0021] It is also advantageous if the feed mandrel or an intermediate piece connected thereto has an outer contour that matches the inner contour of the channel at least in the region arranged in the channel. In this case, particularly good torque transmission is achieved between the feed spindle and the feed mandrel or the intermediate piece connected thereto, so that the feed mandrel can be rotated as required to engage with the blind rivet nut.

[0022] It is also advantageous if the channel has a stop against which a spring acts on the feed mandrel or the intermediate piece. The spring is particularly useful in the case of using an intermediate piece. It presses the intermediate piece into the feed mandrel and thus ensures a torsionally resistant connection between the intermediate piece and the feed mandrel.

[0023] Preferably, the spindle nut is constructed as a ball screw nut (Kugelgewindemutter). The ball screw nut operates with relatively low friction and thus relatively low wear, so that the placement device can be operated for a relatively long period of time even in the case of using a battery as an energy source.

[0024] Advantageously, a feed device acting on a feed mandrel is connected to a feed spindle and a nozzle-shaped part is fixed in a housing through which the feed mandrel is guided, wherein the nozzle-shaped part has an extension pointing to the head of the feed mandrel against which the feed mandrel with the head of the feed mandrel abuts, and wherein the extension generates a predefined spacing between the head of the feed mandrel and the feed device. In the case of placing a blind rivet nut, the feed device must exert a tensile force on the feed mandrel. For this purpose, the feed spindle must be driven in the feed direction. However, a relatively small electric motor has difficulties in exerting the required tensile force at rest. Therefore, it is expedient to first start the motor (hochlaufen). In this case, the feed device can pass through an idle path or an idle stroke (Leerhub) in which no deformation of the blind rivet nut has occurred yet. This idle path is realized in such a way that the feed mandrel is held at a certain distance from the feed device by designing the nozzle-shaped part. Description of the Drawings

[0025] The invention will subsequently be described with reference to preferred embodiments in conjunction with the drawings. Among them:

[0026] Figure 1 A schematic view of a blind rivet fixing device is shown,

[0027] Figure 2 A schematic view of the transmission device of the placement device in the first switching position of the switching coupler is shown,

[0028] Figure 3 A schematic view of the transmission device according to Figure 2 in the second switching position of the switching coupler is shown, and

[0029] Figure 4 A schematic view of the blind rivet fixing device in a state in which it is suitable for placing a blind rivet nut is shown.

[0030] In all the figures, the same and corresponding elements are provided with the same reference signs. Detailed Description of the Invention

[0031] Figure 1 A blind rivet fixing device 1 with a housing 2 is schematically shown, in which a drive motor 3 is arranged. The drive motor 3 is an electric motor which can be supplied with electrical energy by a battery not shown in more detail. Alternatively, of course, a cable can also be provided via which the motor can be connected to an external current source.

[0032] The mounting device 1 has a feed spindle 4 configured as a threaded spindle, which is connected to a feed mechanism 5 presented only schematically. The feed mechanism 5 is arranged in a housing head 6, which has an end side 7 with an opening 8. The housing head 6 can be screwed onto the housing 2. For this purpose, the housing 2 has a thread 9. Another type of fixation is possible, for example a snap connection or a connection with an overnut (Überwurfmutter, sometimes also called an external nut).

[0033] The feed spindle 4 has an external thread 10, with which a ball screw nut 11 is in engagement. The ball screw nut 11 forms part of a transmission device. The ball screw nut 11 has an external toothing 12, which is in engagement with a toothed shaft 13. The toothed shaft 13 is connected to a gear 14, which is connected to another gear 15, which is arranged on the output shaft 16 of the motor 3.

[0034] The feed spindle 4 is rotatably, but axially fixed, supported at its end facing away from the feed mechanism 5 in a mating bracket 17. The mating bracket 17 is arranged torsionally rigid, but axially displaceably, in the housing 2.

[0035] A switching coupling 18 is arranged between the mating bracket 17 and the spindle nut 11, which has a switching bush 19, which can be moved in the direction of the double arrow 20 parallel to the axis of the feed spindle 4.

[0036] Figure 2 The switching bush 19 of the switching coupling 18 in the first switching position is shown. In this first switching position, the feed spindle 4 is torsionally rigidly connected to the mating bracket 17. For this purpose, the switching bush 19 can be axially displaced, but is torsionally rigidly connected to the feed spindle 4. The feed spindle 4 has a non-circular shape in the region of the switching bush 19 in the circumferential direction of the feed spindle 4, for example in the form of a polygon or a multi-wedge assembly 21, so that the switching bush 19 cannot be twisted on the feed spindle 4, but the holding torque acting on the switching bush 19 also acts on the feed spindle 4.

[0037] The switching bush 19 has a first engagement geometry 22, which can engage with a second engagement geometry 23 at the mating bracket 17. When the first engagement geometry 22 and the second engagement geometry 23 are in engagement with each other, a form-fit is formed between the switching bush 19 and the mating bracket 17.

[0038] The switching bush 19 has a third engagement geometry 24. The spindle nut 11 has a fourth engagement geometry 25. As shown in Figure 3As presented, when the third engagement geometry 24 engages with the fourth engagement geometry 25, there is a form - fit connection between the switching sleeve 19 and the spindle nut 11. This is the case which results in the second switching position of the switching sleeve 19. In this case, the spindle nut 11 and the feed spindle 4 are torsionally connected to each other.

[0039] Instead of a form - fit, a force - fit can also be generated, for example by corresponding mating of friction surfaces.

[0040] The mating support 17 has a support assembly 26 which is constructed such that on the one hand it enables a rotational movement of the feed spindle 4 relative to the mating support 17 and on the other hand axially fixes the feed spindle 4 with respect to the mating support 17. The mating support 17 can then be axially moved in the housing 2.

[0041] When a blind rivet is to be placed, its rivet mandrel engages with the engagement structure 5. The placement head of the blind rivet then abuts against the end side 7 of the housing head 6. The switching sleeve 19 is in Figure 2 the first switching position as presented. If then the motor 2 is put into operation, it generates a rotational movement of the spindle nut 11. Since the feed spindle 4 is torsionally held relative to the mating support 17 and thus relative to the housing 2 by the switching sleeve 19, the rotational movement of the spindle nut 11 is converted into a feed movement of the feed spindle 4. The rivet mandrel is pulled and a closing head is formed on the blind side of the blind rivet.

[0042] The feed spindle 4 has a through - channel 27 through which the rivet mandrel can be cleared when it breaks off or is pulled out of the blind rivet.

[0043] When a blind rivet nut is to be placed instead, it is necessary beforehand to screw the feed mandrel 30 with its external thread into the blind rivet nut and, if necessary, modify the part of the feed mechanism 5 acting on the feed mandrel. For this, the feed mandrel 30 ( Figure 4 ) engages with the feed mechanism 5 and the switching sleeve 19 of the switching coupling 18 is brought to Figure 4 the second switching position as presented, in which the spindle nut 11 is torsionally connected to the feed spindle 4. When the motor 3 is put into operation at this time, the feed spindle 4 also rotates together with the spindle nut 11 so that the feed mandrel can be screwed into the blind rivet nut. This helical or spindle movement is not limited to a pre - determined number of rotations here. Also, the feed spindle 4 does not move in the axial direction in this section of the operation of the placement device 1. Figure 3 Once the feed mandrel is screwed far enough into the blind rivet nut, the switching sleeve 19 moves into the first switching position (

[0044] Figure 2 ​), so that another rotation of the spindle nut 11 causes the feed spindle 4 to move in the feed direction and forms the closing head of the blind rivet nut.

[0045] The spindle nut 11 is preferably configured as a ball screw nut with a row of balls 28 in order to keep the friction between the spindle nut 11 and the feed spindle 10 small.

[0046] The motor 3 can be put into operation via an operating device 29 in the form of, for example, a key.

[0047] The switching bushing 19 can be manually or otherwise manipulated.

[0048] Figure 4 A view of the blind rivet fixing device 1 in a state is shown, in which state it is suitable for the placement of blind rivet nuts. For this purpose, the feed mechanism 5 has a feed device 31, which is connected to the feed spindle 4. The feed mandrel 30 is guided through the nozzle-shaped part 32 and screwed into the housing head 6. The nozzle-shaped part 32 has an extension 33, which points into the interior of the housing head 6. The extension 33 holds the feed mandrel head 34 of the feed mandrel 30 at a predetermined distance relative to the feed device 31, that is to say the feed device 31 can, when the feed spindle 4 starts to move, first perform an idle stroke before it reaches the feed mandrel head 34. In other words, the drive motor 3 driving the feed spindle 4 can first start and reach a certain rotational speed before it starts to apply a tensile force to the feed mandrel head 34. The following is therefore particularly advantageous: The drive motor 3 is configured as an electric motor. When the feed device 31 abuts against the feed mandrel head 34, the deformation of the blind rivet nut begins.

[0049] The feed mandrel head 34 can be arranged in the adapter 35. The adapter 35 fills the intermediate space between the feed mandrel head 34 and the inner wall of the feed device 31, so that the feed mandrel head 34 is always held in a defined position in the feed device 31. In the case of using the adapter 35, when the device 31 abuts against the adapter 35, the deformation of the blind rivet nut begins.

[0050] In the present embodiment, the feed mandrel 30 is connected to the feed spindle 4 via an intermediate member 36. The feed mandrel head 34 has, for example, an internal hexagonal edge 37, and the intermediate member 36 can be engaged therein with a corresponding hexagonal edge cross-section 38. The channel 27 also has an inner contour at its end adjacent to the nozzle-shaped part 32, which is different from a circular shape and is suitable for transmitting torque. The intermediate member 36 has an outer contour matching the inner contour of the channel 27. The inner contour of the channel 27 and the outer contour of the intermediate member 36 can be configured, for example, in a hexagonal shape as well.

[0051] Alternatively, it is also feasible to design the feed mandrel 30 with a projection that reaches into the channel 27 and has an outer contour that matches the inner contour of the channel for torque transmission, so that in this way a torsion-resistant connection between the feed spindle 4 and the feed mandrel 30 can be created.

[0052] In addition, a pressure spring 39 is arranged in the channel 27. The pressure spring bears against a stepped piece 40, which is formed by a reduction in the diameter of the channel 27. The pressure spring 39 is responsible for the fact that the intermediate piece 36 is always in engagement with the feed mandrel head 34. The pressure spring 39 can be compensated within certain limits, so that the feed mandrel 30 can move slightly relative to the feed spindle 4 in the axial direction, that is to say in the feed direction.

Claims

1. A blind rivet fixing device (1) with a housing (2), a feed spindle (4) and a drive motor (3), wherein the drive motor is connected to the feed spindle (4) via a transmission device (11 - 15), and wherein the transmission device (11 - 15) has a driven spindle nut (11) which engages with the thread on the feed spindle (4). Wherein, the transmission device (11 - 15) has a switching coupling (18) which non - rotatably connects the spindle nut (11) and the feed spindle (4) to each other in a second switching position, characterized in that the switching coupling (18) non - rotatably connects the feed spindle (4) to the housing (2) in a first switching position.

2. The blind rivet fixing device according to claim 1, characterized in that, the switching coupling (18) has a switching bush (19) which is axially movable on the feed spindle (4).

3. The blind rivet fixing device according to claim 2, characterized in that, the switching bush (19) is non - rotatably connected to the feed spindle (4).

4. The blind rivet fixing device according to claim 2 or 3, characterized in that, the switching coupling (18) generates a force fit and / or a form fit between the switching bush (19) and the spindle nut (11) and / or the housing (2).

5. The blind rivet fixing device according to claim 2 or 3, characterized in that, the switching bush (19) has a first engagement geometry (22) which can engage with a second engagement geometry (23) at the housing (2).

6. The blind rivet fixing device according to claim 2 or 3, characterized in that, the switching bush (19) has a third engagement geometry (24) which can engage with a fourth engagement geometry (25) at the spindle nut (11).

7. The blind rivet fixing device according to claim 5, characterized in that, at least one of the first engagement geometry (22) and the second engagement geometry (23) is arranged at a radial distance from the rotational axis of the feed spindle (4), and the radial distance corresponds to the radius of the switching bush (19).

8. The blind rivet fixing device according to any one of claims 1 to 3, characterized in that, the housing (2) has a mating bracket (17) which non - rotatably connects to the feed spindle (4) in the first switching position.

9. The blind rivet fixing device according to any one of claims 1 to 3, characterized in that, the feed spindle (4) has a continuous longitudinal channel (27).

10. The blind rivet fixing device according to claim 9, characterized in that, The channel (27) has an inner contour different from a circular shape at least in sections adjacent to its ends.

11. The blind rivet fixing device according to claim 10, characterized in that the feed mandrel (30) or an intermediate member (36) connected thereto has an outer contour at least in the region arranged in the channel (27), and the outer contour matches the inner contour of the channel (27).

12. The blind rivet fixing device according to claim 11, characterized in that the channel (27) has a stop (40) against which a spring (39) acting on the feed mandrel (30) or the intermediate member (36) abuts.

13. The blind rivet fixing device according to any one of claims 1 to 3, characterized in that the spindle nut (11) is configured as a ball screw nut.

14. The blind rivet fixing device according to any one of claims 1 to 3, characterized in that a feed device (31) acting on the feed mandrel (30) is connected to the feed spindle (4) and a nozzle-shaped member (32) is fixed in the housing (2), the feed mandrel (30) is guided through the nozzle-shaped member (32), wherein the nozzle-shaped member (32) has an extension (33) pointing towards the feed spindle (4), against which the feed mandrel (30) with a feed mandrel head (34) abuts, and wherein the extension (33) creates a pre-determined spacing between the feed mandrel head (34) and the feed device (31).

15. The blind rivet fixing device according to claim 14, characterized in that the feed mandrel head (34) abuts against the extension via an adapter (35).

16. The blind rivet fixing device according to claim 6, characterized in that at least one of the third engagement geometry (24) and the fourth engagement geometry (25) is arranged at a radial distance from the rotational axis of the feed spindle (4), and the radial distance corresponds to the radius of the switching bush (19).

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