PUSH/PULL ROD

Abstract

The invention relates to a push/pull rod (10) comprising at least one first fastening device (12) with a coupling element (12a) and a shank (12b) which is arranged on it, at least one first connection piece (18), wherein the first fastening device (12) is connected to the first connection piece (18) such that it can be rotated via a threaded arrangement (30) in order to change the length of the push/pull rod (10), a holding device with first and second holding elements interact, and are pressed against one another by means of a spring element (28), wherein the first holding element of the holding device is connected fixedly to the first connection piece (18) for conjoint rotation, and the second holding element is arranged fixedly on the first fastening device (12) for conjoint rotation.

Claims

1-16. (canceled)

17. Push/pull rod (10), comprising: at least one first fastening device (12) with a coupling element (12a) and a shank (12b) which is arranged on it, at least one first connection piece (18), wherein the first fastening device (12) is connected to the first connection piece (18) such that it can be rotated via a threaded arrangement (30) in order to change the length of the push/pull rod (10), a holding device with first and second holding elements which, as viewed in the axial direction, in each case face one another, interact and are pressed against one another by means of a spring element (28), wherein the first holding element of the holding device is connected fixedly to the first connection piece (18) for conjoint rotation, and the second holding element is arranged fixedly on the first fastening device (12) for conjoint rotation, wherein the spring element (28) is active between a region on the first connection piece (18) and a region on the second holding element, and the holding elements in the process releasably lock the rotational movement of the first fastening device (12) relative to the first connection piece (18) in a plurality of rotational positions by way of a predefined locking force, wherein the first connection piece (18) comprises a main body (34) and a sleeve (36) which reaches at least in regions around the two holding elements and the spring element (28), to which sleeve (36) the main body (34) is connected, wherein the sleeve (36) has an internal diameter which ensures a relative movement of the holding elements with respect to one another and of the spring element (28), wherein the sleeve (36) is fixed at least in the axial direction with respect to the main body (34), and wherein the first connection piece (18) holds the holding device with the spring element (28) in the two axial directions, the holding device is configured as a latching device (22) with a first latching element (24) and a second latching element (26), wherein the second latching element (26) has a plurality of latching lugs (26a) which engage into latching grooves (24b) of the first latching element (24), and the first latching element (24) likewise has a plurality of latching lugs (24a) which engage into latching grooves (26b) of the second latching element (26), characterized in that, in the case of the second latching element (26), at least one latching lug (40) is arranged fixedly on a spring element (28).

18. Push/pull rod according to claim 1, characterized in that the sleeve (36) is fixedly connected to the spring element (28) or to a plurality of spring elements.

19. Push/pull rod according to claim 1, characterized in that the sleeve (36), the spring element (28) and the latching lugs (40) of the second latching element (26) form a structural unit which is, in particular, formed in one piece.

20. Push/pull rod according to claim 1, characterized in that the structural unit is made of plastic.

21. Push/pull rod according to claim 1, characterized in that the spring elements (28) are formed as spring arms (38) which project inwardly from the inner wall of the sleeve (36) and have at least one latching lug (40) formed on them.

22. Push/pull rod according to claim 1, characterized in that the shank (12b) of the first fastening element has a groove (12c), the sleeve (36) has at least one projection, which in particular is directed radially inwardly, which projection engages into the groove (12c) of the shank (12b) and, in cooperation with the groove (12c), serves as an anti-rotation lock of the sleeve (36) and of the second fastening element connected to the sleeve (36) with respect to the shank (12b).

23. Push/pull rod according to claim 22, characterized in that the groove (12c) is parallel to the longitudinal axis of the shank (12b) and is formed to be at least as long as the maximum stroke enabled between the first fastening device (12) and the first connection piece (18) by way of the threaded arrangement (30).

24. Push/pull rod according to claim 1, characterized in that the sleeve (36) engages around the shank (12b) of the first fastening device (12), wherein the shank is fixed in the main body (34) so as to be rotatable therein via the threaded arrangement (30) and via the holding device.

25. Push/pull rod according to claim 1, characterized in that the main body (34) and the sleeve (36) are detachably or non-detachably connected to one another.

26. Push/pull rod according to claim 1, characterized in that the main body (34) and the sleeve (36) are connected to one another via a snap-fit connection.

27. Push/pull rod according to claim 1, characterized in that the sleeve (36) is rotatably mounted on the main body (34).

28. Push/pull rod according to claim 27, characterized in that the first connection piece has a groove (12c) on its outer circumference, into which the sleeve (36) engages in regions.

29. Push/pull rod according to claim 1, characterized in that a second fastening device (14) with a shank (14b) and a second connection piece (20) are provided.

30. Push/pull rod according to claim 29, characterized in that the two connection pieces (18, 20) are firmly connected to one another via a connecting rod (16).

31. Push/pull rod according to claim 29, characterized in that the first and second connection pieces (18, 20) are formed differently and that only the first connection piece (18) is provided with the holding device.

32. Push/pull rod according to claim 1, characterized in that the first and second connection pieces (18, 20) are inserted, in particular directly, into a connecting rod (16) and are firmly connected to it, in particular screwed and/or glued to it.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In the drawings,

[0032] FIG. 1 is a side view of an embodiment of a push/pull rod in its extended state;

[0033] FIG. 2 is a side view of the push/pull rod of FIG. 1 in its retracted state;

[0034] FIG. 3 is an exploded side view of the push/pull rod of FIG. 1;

[0035] FIG. 4 is an exploded side view of a connecting rod with the first and second connection pieces of the push/pull rod of FIG. 1 of a first embodiment of the invention, in which the first connection piece is shown without sleeve, spring element and second latching element;

[0036] FIG. 5a is a detailed perspective view of a first fastening device of the push/pull rod of FIG. 1 in which the first connection piece has been inserted, with the first and second latching elements still being offset during rotation, which view does not show the sleeve engaging around the latching device nor the spring element;

[0037] FIG. 5b is a detailed perspective view of the first fastening device of FIG. 5a with the two latching elements meshing;

[0038] FIG. 6 is a perspective exploded view of the front portion of the first connection piece;

[0039] FIG. 7 is a perspective view of the front portion of the first connection piece with the sleeve cut open;

[0040] FIG. 8 is a perspective exploded view of the front portion of a first connection piece and a first fastening device of one embodiment of the invention;

[0041] FIG. 9 is a perspective view of the sleeve of the connection piece of FIG. 8;

[0042] FIG. 10 is a cross-sectional view of the sleeve of FIG. 9;

[0043] FIG. 11 is a sectional view of the front portion of the first connection piece with the fastening device in the assembled state of FIG. 8;

[0044] FIG. 12 is a perspective view, taken at an angle from the front, of the fastening device with the connection piece of FIG. 11, and

[0045] FIG. 13 is a front view of FIG. 12,

DESCRIPTION OF THE INVENTION

[0046] In the description of the embodiments which follows below, identical reference signs or identical component designations are used to designate identical parts, and the disclosures contained in the entire description can be applied mutatis mutandis to identical parts for which identical reference signs or identical component designations are used. Also, the location information given in the description, such as top, bottom, side, etc., refers to the directly described and depicted drawing figure, and for any change of position, such location information is to be applied mutatis mutandis to the new position.

[0047] FIGS. 1 to 7 are views of an embodiment of a push/pull rod 10 which is of a modular design and has a first fastening device 12 at one end thereof and a second fastening device 14 at the second end thereof that is remote in the axial direction, said push/pull rod 10 further comprising a connecting rod 16 arranged between these fastening devices 12, 14 and having a first connection piece 18 on a first side thereof, a second connection piece 20 on a second side thereof, and at least one latching device 22 arranged in the first connection piece 18.

[0048] In the embodiment illustrated in FIGS. 1 to 7, the push/pull rod 10 has fastening devices 12 and 14 spaced apart from one another in the axial direction on both sides, with both fastening devices each comprising a coupling element 12a, 14a and a shank 12b, 14b arranged thereon in this case.

[0049] The latching device 22 is provided in the first connection piece 18 to prevent relative rotational movement of the first fastening 12 with respect to the first connection piece 18 after adjustment of the overall length of the push/pull rod 10. For this purpose, the latching device 22 has latching elements 24, 26 facing each other as viewed in the axial direction and cooperating with one another, which are pressed together or against one another by means of a spring element 28. Spacer washers or thrust washers can additionally be arranged on either side of the spring element 28 to prevent direct contact between the spring element 28 and the first connection piece 18. Such a thrust washer may be made of a stainless steel material to minimize friction between the spring element 28 and the first connection piece 18.

[0050] In addition, a first threaded arrangement 30 is provided between the first fastening device 12, in particular its shank 12b, and the first connection piece 18. Another threaded arrangement 32 is provided between the shank 14b of the second fastening device 14 and the second connection piece 20, see FIG. 3. In order to enable a relative counter-rotational adjustment of the two fastening devices 12 and 14 with respect to the respective associated connection piece 18 or 20, one of the two threaded arrangements, i.e. threaded arrangement 30 of the first connection piece 18 or threaded arrangement 32 of the second connection piece 20, for connection to the associated fastening device 12, 14 is formed as a right-hand thread and the respective other threaded arrangement 30 or 32 is formed as a left-hand thread. When the two fastening devices 12, 14 are in a coupled position relative to components not shown in greater detail here, the fact that the threaded arrangements 30 and 32 are oppositely threaded with respect to one another makes it easy to change the length of the entire push/pull rod 10 by rotating the connecting rod 16, which is firmly connected to the connection pieces 18, 20, relative to the two fastening devices 12, 14.

[0051] The threaded arrangements 30 and 32 have an opposing pitch. This thus allows a continuous adjustment of the distance between the ends of the fastening devices 12, 14. Since the fastening devices 12, 14 are coupled to the components to be supported via the respective coupling element 12a, 14a, they are held in a rotationally fixed manner relative to the associated connection piece 12, 14. Turning the connecting rod 16 with respect to the fastening devices 12, 14 results in a certain amount of tensioning between these parts, via the threaded arrangements 30, 32. To facilitate manual initiation of the rotational movement on the connecting rod 16, its surface may be designed to be grippy.

[0052] The first latching element 24 of the latching device 22 is securely connected to the first connection piece 18, see FIG. 6. The first connection piece 18, like the second connection piece 20, is inserted into the connecting tube 16 and screwed and/or bonded to it. The first latching element 24, the first connection piece 18, the connecting tube 16, and the second connection piece 20 thus form a structural unit. The second fastening device 14 is screwed into the second connection piece 20 via the second threaded arrangement 32a, 32b.

[0053] In this case, the thread 30a of the shank 12b is designed as an external thread and the thread 30b of the first connection piece 18 is designed as an internal thread. The thread 32a of the shank 14b is also formed as an external thread and the thread 32b as an internal thread. One of the two threads, i.e. thread 30b of the first connection piece 18 and the thread 32b of the second connection piece 20, is designed as a right-hand thread for connection to the respective fastening device 12, 14, and the respective other thread 30b, 32b is designed as a left-hand thread.

[0054] The second latching element 26 includes a pin-shaped projection 26c that engages into a groove 12c of the first fastening device 12. As a result, the second latching element 26 is connected to the first fastening device 12 for conjoint rotation, as can best be seen from a consolidated view of FIGS. 5a and 5b. Preferably, a plurality of projections 26c and a plurality of respective associated grooves12c can be provided over the circumference, for better and more stable force transmission.

[0055] The first and second latching elements, 24, 26 resp., are in the form of a latching disc. The first latching element 24 has latching lugs 24a and latching grooves 24b, and the second latching element 26 has latching lugs 26a and latching grooves 26b formed in the same manner as those of the first latching element 24. The latching elements 24 and 26 are mounted with their latching lugs 24a, 26a and latching grooves 24b, 26b facing each other. In this case, the latching lugs 24a of the first latching element 24 engage into latching grooves 26b of the second latching element 26, and the latching lugs 26a of the second latching element 26 engage into latching grooves 24b of the first latching element.

[0056] The latching elements 24, 26, which are designed as latching discs, each have a central opening which serves to receive the shank 12b of fastening device 12 or the shank 14b of fastening device 14.

[0057] The twist angle and the adjustment possibilities between the two latching elements 24, 26 depend on the size of the latter and on the number of latching lugs 24a, 26a and latching grooves 24b, 26b. If latching discs are provided that have a higher number of latching lugs 24a, 26a and latching grooves 24b, 26b, finer latching adjustment can be achieved than is possible with a smaller number of latching lugs 24a, 26a and latching grooves 24b, 26b.

[0058] Regardless of this, however, it would still be possible to provide the latching elements 24, 26 with a friction lining or the like, instead of latching grooves, thus allowing an even finer adjustment of the overall length of the push/pull rod 10. This can also be achieved by providing some kind of microstructure on the two surfaces of the latching elements 24, 26 that face one another.

[0059] The first connection piece 18 includes a main body 34 and a sleeve 36. The sleeve 36 engages around the outside of the latching elements 24, 26 and has its end facing the main body 34 firmly connected to the main body 34 on the end side facing the main body 34. On the side of the sleeve 36 that is remote from the main body 34, the sleeve 36 has an inwardly directed circumferential flange 36a which forms a support shoulder 36b for the spring element 28 on the inside, see FIG. 7.

[0060] The spring element 28 of the latching device 22 is supported via its first end 28a on the support shoulder 36b provided on the sleeve 36 of the first connection piece 18, and via its second end 28b on the second latching element 26. The spring element 28, the sleeve 36, the first and second latching elements 24, 26 are all arranged around the shank 12b of the first fastening device 12, which shank is screwed into the first connection piece 18. The first latching element 24 in turn, being firmly connected to the main body 34, is supported on the main body 34 of the first connection piece 18. Due to the spring element 28 being supported on the support shoulder 36b, and the thus resulting spring force on the latching elements 24, 26 and on the main body 34 and the sleeve 36 and thus on the first connection piece 18, radial anti-rotation lock is effected, via the latching latching lugs 24a and latching grooves 24b, of the external thread 30a on the shank 12b and of the internal thread 30b in the first connection piece 18. The sleeve 36 is spaced laterally from the latching elements 24, 26 and the spring element 28 so that it is free to move relative to the first connection piece 18 and in the axial direction against the spring force of the spring element 28 when the first fastening device 12 is rotated. Since the main body 34 on the one side and the sleeve 36 connected to the main body 34 on the other side hold the latching device 22 with the spring element 28 in the axial direction, the holding force acting on the latching device 22 will always be the same, regardless of the extended position of the first fastening device 12 relative to the first connection piece 18.

[0061] The latching elements 24, 26, which are designed as latching discs, are each independently arranged for conjoint rotation on different components of the push/pull rod 10 and are additionally braced against each other by the spring element 28. The second latching element 26 is slightly adjustable in the axial direction against the spring force of the spring element 28, whereby the second latching element 26 can perform a rotational movement of the first fastening device 12 relative to the first connection piece 18 when a torque is applied relative to the first latching element 24, and can releasably lock the first fastening device 12 in a plurality of rotational positions with a predefined locking force. In this case, the locking force corresponds to the spring force of the spring element 28, as the latching lugs 24a, 26a slide against each other, thereby axially displacing the second latching element 26 until the latching lugs 24a, 26a engage into the adjacent latching groove 24b, 26b. This is repeated as long as an appropriate torque is applied between the connecting rod 16 and the first fastening element 12, i.e. until the desired final adjustment of the push/pull rod 10 has been reached. As the first fastening device 12 rotates, it rotates into or out of the first connection piece 18, depending on the direction of rotation, via the threaded assembly 30. Accordingly, the second fastening device 14 also rotates into or out of the second connection piece 20, via the threaded arrangement 32.

[0062] In this process, the pin-shaped projection 26c of the second latching element 26 accordingly moves along in the groove 12c of the first fastening element 12. The groove 12c is designed to be as long as the maximum stroke of the first fastening element 12 relative to the first connection piece 18.

[0063] FIGS. 8 to 13 are views of an embodiment of the push/pull rod 10 according to the invention, and the same reference signs or component designations are again used to designate identical parts as in the preceding FIGS. 1 to 7. To avoid unnecessary repetition, reference is made to the detailed description provided above with reference to FIGS. 1 to 7.

[0064] The main body 34 of the first connection piece 18 is provided with a groove 34a adjacent to the first latching element 24, see FIG. 8 and FIG. 11. At its end facing the main body 34, the sleeve 36 is provided with inwardly directed pins 36c, and with slots 36d that are arranged on both sides adjacent to the pins 36c. The sleeve 36 is pushed over the latching element 24 via the pins 36c until the pins 36c snap into the groove 34a of the main body 34. As a result, the sleeve 36 is fixed in the axial direction, but is rotatably mounted relative to the main body 34.

[0065] The design of the first fastening device 12 is unchanged as compared to that of the first embodiment.

[0066] The sleeve 36 is provided with a single or a plurality of spring arm(s) 38, which is/are provided on the inside in the area of the end of the sleeve 36 facing away from the main body 34 and are directed inwards. Each spring arm 38 has a latching lug 40 provided thereon. The spring arms 38 with the latching lugs 40 are arranged in a circle and form a through opening 42 for the shank 12b of the first fastening device 12.

[0067] In addition, two projections 44 are provided between two adjacently disposed spring arms 38, with the two projections 44 being offset by 180° from each other. Accordingly, the grooves 12c in the shank 12b are also offset by 180° from each other. The projections 44, the spring arms 38 and the latching lugs 40 are preferably integrally formed from the same plastic material and form a structural unit. This unit can be manufactured in a simple way by plastic injection molding.

[0068] In both embodiments, the connection pieces 18 and 20 are firmly connected to the connecting rod 16, preferably screwed and/or glued to it. The connection piece 18 includes the latching device 22. The connection piece 20 does not have such a holding device. In this respect, the connection pieces 18 and 20 can have different designs.

LIST OF REFERENCE SIGNS

[0069] TABLE-US-00001 10 push/pull rod 12 first fastening device 12a coupling element 12b shank 12c groove 14 second fastening device 14a coupling element 14b shank 16 connecting rod 18 first connection piece 20 second connection piece 22 latching device 24 first latching element 24a latching lugs 24b latching grooves 26 second latching element 26a latching lugs 26b latching grooves 26c pin-shaped projection 28 spring element 28a first end of spring element 28 28b second end of spring element 28 30 threaded arrangement 30a threaded arrangement - part of shank 12b 30b threaded arrangement - part of the first connection piece 18 32 threaded arrangement 32a threaded arrangement - part of shank 14b 32b threaded arrangement - part of second connection piece 20 34 main body of first connection piece 18 34a groove 36 sleeve of first connection piece 18 36a flange of sleeve 36 36b support shoulder of sleeve 36 36c pin of sleeve 36 36d slot of sleeve 36 38 spring arm 40 latching lug 42 through hole 44 projection