CROSS-REFERENCE TO RELATED APPLICATION
This application is a U.S. National Phase Patent Application based on International Application No. PCT/EP2010/068061 filed Nov. 23, 2010, the entire disclosure of which is hereby explicitly incorporated by reference herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a device for setting fastening elements.
2. Description of the Related Art
One known device is disclosed by DE 10 2005 054 719 B3. The known device is provided with a set control link having a set control slot, and with a rivet ram connected to a set control pin which in turn engages in the set control slot. Also present is a feed shaft rod to which the set control link is non-rotatably mounted. The device is further equipped with a drive unit, by means of which the feed shaft rod can be driven to rotate in order to move the rivet ram between a retracted, pre-installation position and an extended, installation position. In this way, a fastening element embodied particularly as an expansion rivet can be set mechanically by, for example, pushing a rivet pin in between spring arms of an expansion rivet via the movement of the rivet ram. In this device, a rivet holding head connected to the feed rod protrudes relatively little beyond an end face of a receiving housing, thus resulting in an overall compact design.
SUMMARY OF THE INVENTION
The present invention provides a device for setting fastening elements, which is distinguished by the fact that fastening elements can be applied at the setting location with a relatively precisely defined setting force.
By virtue of the fact that a pressure force sensor unit is present and is connected directly to the feed shaft rod in the device according to the invention, the fastening elements can be set with pressing forces that can be measured very precisely directly at the spatially very limited application site.
In one form thereof, the present invention provides a device for setting fastening elements, including a rivet ram, a feed shaft rod, a drive unit by means of which the feed shaft rod can be driven to rotate, and at least one link and a link control that has a control pin assigned to the or a link and by means of which, when the feed shaft rod is rotated, the rivet ram is movable between a retracted, pre-installation position and an advanced, installation position, characterized in that mounted to the feed shaft rod is an axial force transmission element that is stationary in the axial direction relative to the feed shaft rod and in that a pressure force sensor unit is present, which, in a setting position of the feed shaft rod with the axial force transmission element, can be acted upon by a pressing force exerted on the feed shaft rod via a mechanical flux chain.
BRIEF DESCRIPTION OF THE DRAWINGS
The above mentioned and other features and objects of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a partially cut-away perspective view of an exemplary embodiment of a device according to the invention;
FIG. 2 is a perspective exploded view particularly of a feed shaft rod, a set control link and a feed link of the exemplary embodiment according to FIG. 1;
FIG. 3 is a view of the feed link composed of two feed link shells in the exemplary embodiment according to FIG. 1 and FIG. 2;
FIG. 4 is a partially cut-away perspective view of a pressure force sensor unit in the exemplary embodiment according to FIG. 1;
FIG. 5 is a perspective sectional view of the exemplary embodiment according to FIG. 1 with the feed shaft rod in a starting position;
FIG. 6 is a sectional perspective view of the exemplary embodiment according to FIG. 1 with the feed shaft rod in a breakout position;
FIG. 7 is a sectional perspective view of the exemplary embodiment according to FIG. 1 with the feed shaft rod in a setting position; and
FIG. 8 is a sectional perspective view of the exemplary embodiment according to FIG. 1 with the feed shaft rod in the setting position and a rivet ram in an advanced, installation position.
Corresponding reference characters indicate corresponding parts throughout the several views. Although the exemplifications set out herein illustrate embodiments of the invention, in several forms, the embodiments disclosed below are not intended to be exhaustive or to be construed as limiting the scope of the invention to the precise forms disclosed.
DETAILED DESCRIPTION
FIG. 1 shows, in a partially cut-away perspective view, an exemplary embodiment of a device according to the invention for setting fastening elements particularly in the form of expansion rivets 1 having a disk-shaped support disk 2, spring arms 3 formed on one side of the support disk 2, and a rivet pin 4 that can be shifted from a pre-installation position to a final installation position by being pushed through an opening in the support disk 2 and between the spring arms 3 to spread the latter.
The device according to FIG. 1 is configured as pistol-like and has a receiving housing 5 with a pistol-like grip 6, at the free end of which is disposed a battery compartment 7 for connection to a battery, not shown in the representation of FIG. 1, for supplying electrical energy. Provided on the opposite side of the grip 6 from the battery compartment 7 is a trigger button 8 by means of which a drive unit 10 having an electric motor and a transmission can be actuated via a control electronics 9.
The device according to the invention as represented in FIG. 1 is configured with a rivet holding head 11, which operates to hold an expansion rivet 1 by the rivet pin 4 protruding in the pre-installation position beyond the support disk 2 on the side facing away from the spring arms 3, and which is disposed at an end, directed away from the receiving housing 5, of a head sleeve 12, which by its end directed away from the rivet holding head 11 passes into the receiving housing 5 and surrounds a breakout link 13 of a link control.
The breakout link 13, in turn, is mounted non-rotatably to an end, directed toward the head sleeve 12, of a feed shaft rod 14 rotatably mounted in a bearing part 15. The end of feed shaft rod 14 directed away from breakout link 13 passes into a feed link 16 that is part of the link control and is disposed non-rotatably relative to the receiving housing 5.
Also present is an elongate rivet ram 17, which in the representation of FIG. 1 extends into the feed link 16, and runs from feed link 16 all the way through feed shaft rod 14 into the end of head sleeve 12 that carries rivet holding head 11.
It can further be seen from the representation of FIG. 1 that the device according to the invention comprises a pressure force sensor unit 18, which is disposed, in a mechanically protected manner, on the side of feed link 16 facing away from head sleeve 12 in the back section of the receiving housing 5 of the device according to the invention.
Finally, it can also be seen from the representation of FIG. 1 that the expansion rivets 1 are attached by their support disks 2 to two facing feed belts 19, which can be conveyed to the rivet holding head 11 via a rail arrangement disposed on the outside of the receiving housing 5.
FIG. 2 shows, in a perspective view, the head sleeve 12, the breakout sleeve 13, the feed shaft rod 14, the bearing part 15 and the feed link 16 according to the exemplary embodiment of FIG. 1. It can be seen from the representation of FIG. 2 that disposed at the end of head sleeve 12 surrounding the breakout link 13 is a breakout control pin 20, which is part of the link control and is adapted to engage in a breakout control slot 21 formed in the breakout link 13. The breakout control slot 21 has a circumferentially extending front section 22 disposed directly at the end of breakout link 13 directed toward rivet holding head 11, and an also circumferentially extending back section 23, which is offset away from rivet holding head 11 with respect to front section 22. Extending between front section 22 and back section 23 is an obliquely extending breakout slanted section 24.
It can also be seen from FIG. 2 that the bearing part 15 surrounding feed shaft rod 14 houses a drive gear 25, which is non-rotatably connected to feed shaft rod 14 and is coupled to the drive unit 10 (not visible in the representation of FIG. 2), in order to drive the feed shaft rod 14 to rotate. Also attached to bearing part 15 are connecting rods 26, 27 provided for displaceable engagement with feed link shells 28, 29 that form the feed link 16.
At its opposite end from the breakout link 13, feed shaft rod 14 comprises a feed bearing ring 30 and a set control link 31, which are also non-rotatably connected to feed shaft rod 14. The feed bearing ring 30 carries a feed control pin 32, which is part of the link control and protrudes radially past the feed bearing ring 30, and which also functions as an axial force transmission element, as will be explained in more detail subsequently below. Formed in set control link 31 is a set control slot 33, provided in particular with a set section 34 extending in the axial direction, with a clamping section 35 extending from the end directed away from the breakout link 13 spirally away from said breakout link 13, and with a holding section 36 extending substantially circumferentially from the end of the clamping section 35 directed away from set section 34 toward the end of set section 34 directed away from breakout link 13.
It can also be recognized from the representation of FIG. 2 that the feed link shells 28, 29 forming the feed link 16 are configured with a feed control slot 37, which is provided to engage with the feed control pin 32.
Disposed between the feed link shells 28, 29, is a hollow-cylindrical bearing sleeve 38, which carries a radially outwardly projecting slide block 39 and a radially inwardly extending set control pin 40 that is part of the link control and is provided to engage with the set control slot 33. Mounted centrally inside the bearing sleeve 38 is the rivet ram 17.
The rivet ram 17 is disposed centrally in bearing sleeve 38, whose slide block 39 is slid in a slide groove 41 extending in the axial direction in a feed link half-shell 28, to connect bearing sleeve 38 non-rotatably to feed link 16.
A setting compression spring 42 engages in the bearing sleeve 38 at its end directed away from the rivet ram 17, and bears at one end against the rivet ram 17 and at the other end against a stop plate 43 that faces the bearing sleeve 38.
FIG. 3 shows the feed link shells 28, 29 forming the feed link 16, in a view of the inner side that faces the feed control pin 32. It is clearly evident from the representation of FIG. 3 that the feed control slot 37 has a protrusion section 44 which in the intended arrangement faces the breakout link 13, and a retraction section 45 opposite the protrusion section 44, between which extend spirally extending, stepless, slanted feed sections 46, 47.
FIG. 4 is a partially cut-away perspective view of the pressure force sensor unit 18 of the exemplary embodiment shown in FIG. 1. It can be seen from FIG. 4 that the pressure force sensor unit 18, which is disposed in a bearing block 48, is provided with a sliding element in the form of a sliding sleeve 49, which is disposed displaceably in the longitudinal direction in a sleeve guide 50 formed in the bearing block 48, and one end of which confronts the feed control pin 32 forming the axial force transmission element. In the end of sliding sleeve 49 directed away from feed control pin 32, a press ram 51 is anchored tightly in the axial direction, and protrudes past the end of sliding sleeve 49 directed away from feed control sleeve 32 and is in contact with a pressure sensor 52 fixedly anchored in the bearing block 48. The pressure sensor 52 is connected via a measurement-value converter/amplifier unit to the control electronics 9, which in turn is connected to a release indicator 53, which in this exemplary embodiment functions optically.
By means of the release indicator 53, a release signal can be output as soon as the pressing force received via the pressure sensor 52 reaches or exceeds a setting force. This minimum pressing force corresponds to a predetermined setting force which the pressure sensor 52 reaches via a mechanical flux chain, specifically, in this exemplary embodiment, the link control, including the expansion rivet 1 to be set, the head sleeve 12, the breakout control pin 20, the breakout link 13, the feed shaft rod 14, the feed bearing ring 30, the feed control pin 32, the sliding sleeve 49 and, finally, the press ram 51.
The release display also serves to output a stop signal to prevent overload damage as soon as the pressing force received via the pressure sensor 52 exceeds a maximum setting force. This maximum pressing force corresponds to a predetermined maximum setting force which the pressure sensor 52 reaches via the mechanical flux chain. If the maximum setting force is exceeded, to prevent overload damage an inhibition signal is also sent to the control electronics 9 to suppress the triggering of a setting operation.
The manner of operation of the above-described exemplary device according to the invention will now be described with reference to the representations of FIG. 5 to FIG. 8.
FIG. 5 is a perspective sectional representation of the exemplary embodiment of FIG. 1 with the rivet ram 17 in a retracted, pre-installation position, in which the set control pin 40 is disposed in the holding section 36 of the set control slot 33 and the setting compression spring 42 is under maximum tension. The feed shaft rod 14 and thus also the head sleeve 12 mounted thereto are also in a retracted, starting position, in which the feed control pin 32 is disposed in the refraction section 45 of the feed control slot 37 and the slide block 38 is disposed in a slide rail 55 provided in a guide plate 54 and aligned with the slide slot 41, on the side of feed link 16 facing away from feed bearing ring 30. The rivet pin 4 of the expansion rivet 1 disposed at an exit face 56 of the device according to the invention passes through a slit dimensioned for this purpose and into the rivet holding head 11, the support disk 2 still being connected to the feed belts 19.
Owing to the arrangement of the breakout control pin 20 in the retraction section 23 of the breakout control slot 21, the head sleeve 12, in order to permit unimpeded entry by the rivet pin 4, is in a retracted, ready position in which the end face of the rivet holding head 11 facing the support disk 2 is spaced apart from the support disk 2.
FIG. 6 shows the arrangement of FIG. 5 during a setting cycle, in a transitional position of feed shaft rod 14 in which it is rotated with respect to the arrangement of FIG. 5, and in which the breakout control pin 20 is now disposed in the front section 22 of the breakout control slot 21 and, by corresponding advancement of the head sleeve 12, the expansion rivet 1 has been broken out of the feed belts 19 and the end of the rivet pin 4 directed away from the support disk 2 is surrounded by the rivet holding head 11. The feed shaft rod 14 is in the same position as in the representation of FIG. 4, since the feed control pin 32 is still in the retraction section 45 of the feed control slot 37 and the set control pin 40 is still in the holding section 36 of the set control slot 33.
FIG. 7 shows the arrangement according to FIG. 5 and FIG. 6 with the assembly comprised of head sleeve 12, feed control rod 14 and bearing sleeve 38 in an advanced, setting position, in which the expansion rivet 1 is now a relatively large distance from the exit face 56. This setting position, which permits very easy access even to deep-lying application sites or sites that would be hard to access with a shorter projecting length of head sleeve 12 past exit face 56, has been arrived at from the arrangement of FIG. 6 by further rotation of the feed shaft rod 14, brought about by the feed control pin 32 having moved from the retraction section 45 through a slanted feed section 46, 47 into the protrusion section 44. The setting compression spring 42 remains under tension, since the set control pin 40 is still positioned in the holding section 36 of the set control slot 33.
In the setting position of the feed shaft rod 14 and the pre-installation position of the rivet ram 17 depicted in FIG. 7, in an intended manipulation of the device according to the invention, the expansion rivet 1 is moved to the setting location and, for example, pressed against a support element (not shown in FIG. 7) placed on a carrier element (also not shown in FIG. 7), the spring arms 3 being engaged in openings provided in the carrier element and in the support element. By the pressing of the inventive device against the support element, the pressure sensor 52 is acted upon by a pressing force via the flux chain described in connection with FIG. 4. When the predetermined threshold value, as the minimum setting force, is reached or exceeded, thereby activating the release display 53, the trigger button 8 is unlocked via the control electronics 9.
FIG. 8 shows the arrangement of FIG. 5 to FIG. 7 after a pressing of the trigger button 8 has caused the feed shaft rod 14, with the rivet ram 17, to rotate from the arrangement of FIG. 7 to an advanced, installation position, the rivet pin 4 having been pushed in between the spring arms 3 of the now set expansion rivet 1. In this installation position, the setting compression spring 42 is in a relatively relaxed arrangement, after moving the rivet ram 17 abruptly away from the stop plate 43 once the set control pin 40 has been guided into the set section 34 of the set control slot 33.
Proceeding from the arrangement of FIG. 8, after the trigger button 8 is released, as a result of further rotation of the feed shaft rod 14 there is a return to the starting position and pre-installation position depicted in FIG. 5, and the next expansion rivet 1 is introduced into the rivet holding head 11 until the arrangement of FIG. 7 is reached again.
While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.
Patent Grant
9199300
