STEERING COLUMN FOR A MOTOR VEHICLE AND METHOD FOR PRODUCING A STEERING COLUMN

Abstract

A steering column for a motor vehicle may include a steering shaft that is rotatably supported in a cover unit, an interface for fitting a steering column switch fixed relative to the cover unit, and a transmission element connected to the steering shaft so as to conduct torque by way of a securing means. The transmission element may include actuation means that is movable into operational engagement with the steering column switch fitted to the interface. The transmission element may be constructed in one piece together with at least one securing means for a rotationally secure connection to the steering shaft.

Claims

1.-10. (canceled)

11. A steering column comprising: a steering shaft that is rotatably supported in a cover unit; an interface for fitting a steering column switch that is fixed relative to the cover unit; and a transmission element that is securely and rotatably connected to the steering shaft by way of securing means so as to conduct torque, wherein the transmission element is formed as an integral piece with the securing means, the transmission element comprising actuation means that is movable into operational engagement with the steering column switch fitted to the interface.

12. The steering column of claim 11 wherein the integral piece is a single piece.

13. The steering column of claim 11 wherein the securing means comprises a positive-locking element that engages in a corresponding positive-locking receiving member of the steering shaft.

14. The steering column of claim 11 wherein the securing means comprises a non-positive locking element that is connected to the steering shaft in a frictionally engaging manner.

15. The steering column of claim 11 wherein the securing means comprises a resilient element.

16. The steering column of claim 11 wherein the transmission element is annular and at least partially engages around the steering shaft in a peripheral direction.

17. The steering column of claim 11 wherein the securing means comprises a securing sleeve configured as a tubular portion.

18. The steering column of claim 11 wherein the transmission element is a sheet metal component.

19. The steering column of claim 11 wherein the interface comprises on the cover unit a receiving portion that is disposed in an axial direction adjacent to the transmission element.

20. A method for producing a steering column that includes a steering shaft that is rotatably supported in a cover unit, an interface for fitting a steering shaft switch that is fixed relative to the cover unit, and a transmission element that is connected in a torque-conducting manner to the steering shaft by way of securing means and that comprises actuation means configured to be brought into operational engagement with the steering shaft switch fitted to the interface, the method comprising: fitting the transmission element, which is formed as an integral piece with the securing means for connection to the steering shaft, in an axial direction to the steering shaft; and fixing the transmission element, without additional connection means, directly in a rotationally secure manner to the steering shaft so as to be self-retaining.

21. The method of claim 20 comprising, after fixing the transmission element to the steering shaft, fitting the steering shaft switch to the interface of the cover unit directly or indirectly, wherein the actuation means of the transmission element is brought into operational engagement with the steering shaft switch.

22. The method of claim 20 wherein the integral piece is a single piece.

Description

DESCRIPTION OF THE DRAWINGS

[0032] Advantageous embodiments of the invention are explained in greater detail below with reference to the drawings, in which:

[0033] FIG. 1 is a schematic, perspective illustration of a steering column having a steering shaft switch which is fitted thereto,

[0034] FIG. 2 is a detailed view of the steering column from FIG. 1,

[0035] FIG. 3 shows the steering column according to FIG. 1 in an axially separated state,

[0036] FIG. 4 is an axial view of the rear end of the steering column according to FIG. 1,

[0037] FIG. 5 is a partial longitudinal section in the direction of the longitudinal axis through the steering column according to FIG. 1,

[0038] FIG. 6 is a schematic perspective view of a steering shaft in a first embodiment,

[0039] FIG. 7 is an axial view of the steering shaft according to FIG. 6,

[0040] FIG. 8 is a schematic perspective view of a steering shaft in a second embodiment,

[0041] FIG. 9 shows the transmission element of the steering shaft from FIG. 8 in the removed state,

[0042] FIG. 10 shows the transmission element according to FIG. 9 in the separated state.

EMBODIMENTS OF THE INVENTION

[0043] In the different figures, identical components are always given the same reference numerals and are therefore generally also only set out or mentioned once.

[0044] FIG. 1 shows a steering column 1 according to the invention as a perspective view obliquely toward the rear end on which in the vehicle a steering wheel which is not illustrated in this instance is assembled.

[0045] Via the retention unit 11, the steering column 1 can be secured to a vehicle bodywork which is not illustrated in this instance. The retention unit 11 has two downwardly protruding side members 12 between which the outer cover pipe 14 of an actuation unit 13 is arranged. In the cover pipe 14, a steering shaft 15 is rotatably supported about the longitudinal axis 16 thereof. At the rear end region of the steering shaft 15, a portion 151 for fitting a steering wheel which is not illustrated is formed.

[0046] By means of a clamping device which has a clamping axle 17 which extends through both side members 12 transversely relative to the longitudinal axis 16, the side members 12 can be pressed by means of manual movement of an actuation lever 18 from the outer side against the cover pipe 14 and consequently tensioned. Different construction types of clamping devices which implement a rotational movement of the actuation lever 18 in order via the clamping axle 17 to pull the side members against each other are known in the prior art, for example, as cam or tilting pin clamping devices. In the secured state of the clamping device, the cover pipe 14 is clamped between the side members 12 and consequently the actuation unit 13 is connected to the retention unit 11 in a non-positive and/or positive-locking manner so that the steering wheel position is fixed in the vehicle inner space. In the released state of the clamping device, the clamping connection to the retention unit 11 is released so that the actuation unit 13 can be adjusted relative to the retention unit 11 in the direction of the longitudinal axis 16 and in most cases also transversely relative thereto in the vertical direction 19.

[0047] There is fitted to the actuation unit 13 a steering shaft switch 2 which is constructed as a steering shaft switch module which generally combines a plurality of electrical switching devices, in the illustrated embodiment, for example, an indicator switch 21 with a manually actuatable switch lever, and, for example, a headlight switch, also with a switch lever.

[0048] FIGS. 2 and 3 show detailed views of the steering column 1, wherein FIG. 3 shows a separated view prior to assembly. The steering shaft switch 2 has a continuous securing opening 22 which for assembly is placed from the rear parallel with the longitudinal axis 16 on an interface 3 which is formed on the actuation unit 13, as indicated in FIG. 3 with the arrow. The interface 3 has in the example illustrated a cylindrical receiving portion 31 on the cover pipe 14 which can be inserted coaxially in a positive-locking manner in a corresponding hollow-cylindrical counter-portion 23 in the securing opening 22. Furthermore, there may be provided on the cover pipe 12 assembly openings 32 which can be connected by means of corresponding assembly elements to the steering shaft switch 2.

[0049] On a securing portion 152 of the steering shaft 15, a transmission element 4 according to the invention is fitted in a rotationally secure manner in the region of the interface 3. The transmission element 4 is located in the direction of the longitudinal axis 16 adjacent to the receiving portion 31 so that it can be rotated together with the steering shaft 15 relative to the receiving portion 31 about the longitudinal axis 16.

[0050] The steering shaft switch 2 has a plurality of electrical switch elements which can be operated manually, including the indicator switch 21.

[0051] In the region of the through-opening 22, the steering shaft switch 2 has a carrier element 24 which in the assembly state shown in FIG. 2 is located in the region of the interface 3 so that it is in torque-conducting operational engagement with the transmission element 4. To this end, the carrier element 24 may have a journal 25 which protrudes radially inward into the through-opening 22 and which engages with respect to the peripheral direction in a positive-locking manner in a corresponding actuation means of the transmission element 4 which in the example illustrated is constructed as a radial formation 41 in the outer periphery of the transmission element 4. In order to improve the assembly of the steering shaft switch 2, an auxiliary assembly member 155 in the form of a profiled sleeve which is formed from plastics material can be used, wherein the auxiliary assembly member 155 is placed prior to the assembly of the steering shaft switch 2 on the portion 151 of the steering shaft 15. The auxiliary assembly member 155 comprises a guide channel 156 which narrows from the steering-wheel-side end of the steering shaft. The guide channel 156 guides the journal 25 of the steering shaft switch module 2 during the assembly to the formation 41 of the transmission element 4. Consequently, the guide channel 156 acts as an auxiliary introduction member for the coupling between the journal 25 and the formation 41. Consequently, the assembly can be carried out in a secure and simple manner. After the assembly of the steering shaft switch, the auxiliary introduction member 155 can be readily removed from the portion 151 of the steering shaft 15 and subsequently the steering wheel can be assembled.

[0052] The carrier element 24 acts as an actuator for a return device of the indicator switch 21 which is not illustrated in detail. The return device deactivates the switched-on indicator switch 21 independently when the steering shaft 15 is turned back after a turning maneuver.

[0053] FIG. 4 shows the assembled state from FIG. 2 again as an axial view from the rear. It can be seen how the carrier element 24 engages with the journal 25 radially in the formation 41 and is thereby connected to the transmission element 4 in a torque-conducting manner.

[0054] In FIG. 5, a longitudinal section through the actuation unit 13 in the region of the interface 3 is illustrated. It can be seen therein how the transmission element 4 is fitted on the securing portion 152 of the steering shaft 15 axially adjacent to the receiving portion 31 of the cover pipe 14. The coupling between the cover pipe 14 and the steering shaft switch 2 is, however, not carried out exclusively via the receiving portion 31.

[0055] In an embodiment which is not illustrated, the steering shaft switch is secured to a metal plate which is orientated orthogonally with respect to the longitudinal axis of the steering shaft and which is secured to the cover pipe. Other interfaces between the cover pipe and the steering shaft switch are also conceivable and possible and sufficiently known from the prior art.

[0056] The specific configuration of the transmission element 4 according to the invention becomes clear together with the illustrations in FIGS. 6 and 7. Accordingly, this embodiment of the transmission element 4 is constructed in an annular manner and has the basic shape of a flat circular ring or an annular disk which extends parallel with a radial plane of the steering shaft 15. This embodiment of the transmission element may, for example, be constructed as a molded sheet metal component, preferably from sheet steel.

[0057] As already mentioned above, the transmission element 4 has in the outer periphery thereof a radial formation 41 which forms an actuation means for torque-conducting coupling to the carrier element 24 of the indicator switch 21. There may be provided at least one other recess 42, where applicable also a plurality, for example, for actuating corresponding switch elements or the like. The recess 42 may also act as an auxiliary orientation member during the assembly of the transmission element 4 on the steering shaft 15.

[0058] For rotationally secure, that is to say, torque-conducting securing to the steering shaft 15, the transmission element 4 has a positive-locking element 43 which protrudes radially into the annular opening thereof, and which engages in the corresponding longitudinal groove 153 in the securing portion 152 in a positive-locking manner. In addition, additional positive-locking elements 44 which engage in longitudinal grooves 154 may be provided.

[0059] Furthermore, the securing means may comprise centering projections 45 which also protrude radially inward into the open annular cross-section. Preferably, a plurality, in the example shown, six, of the centering projections 45 are arranged in a state distributed over the periphery. The centering projections 45 do not engage in a positive-locking manner, but are instead supported in a radial direction on the cylindrical outer periphery of the steering shaft 15 and can ensure as non-positive-locking elements a frictionally engaging connection.

[0060] The positive-locking elements 43, 44 and the centering projections 45 form securing means according to the invention which are constructed in an integral manner with the transmission element 4. The transmission element 4 which is in the form of an annular disk in terms of its basic shape may be constructed as a stamped sheet metal component, preferably of sheet steel.

[0061] Another embodiment of a transmission element 4 according to the invention is illustrated in FIGS. 8, 9 and 10. This also has a flat annular disk 46 which has formations 42 in the outer periphery thereof. In place of the formation 41 of the first embodiment, there are provided in this instance engagement elements 47 to which there can be fitted in a radial direction an adapter piece 5 which itself has the formation 41 for coupling to the carrier element 24 of the steering shaft switch 2.

[0062] For connection to the transmission element 4, the adapter piece has connection openings 51 in which the engagement elements 47 can be received in order to position and retain the adapter piece 5. Furthermore, it comprises in an axial direction resilient locking elements 52 which can be brought axially into engagement with the through-opening of the annular disk 46 so that the adapter piece 5 is securely engaged on the transmission element 4.

[0063] There is on the annular disk 46 a tubular-portion-like, conically converging securing sleeve 48 which has multiple slots over the periphery thereof in order to form a plurality of segment-like resilient elements 49. The passage cross-section which is formed inside these resilient elements 49 is sized in such a manner that the securing sleeve 48 can be axially pressed onto the securing portion 152 of the steering shaft 15, wherein the resilient elements 49 as a result of their resilient force bring about a non-positive-locking connection of the transmission element 4 to the steering shaft 15, that is to say, form non-positive-locking elements for frictionally engaging connection and consequently securing means in the context of the invention.

[0064] According to the invention, the resilient elements 49 are constructed integrally with the transmission element 4. Preferably, the second illustrated embodiment of the transmission element 4 is also constructed as a sheet metal component, preferably as a cold-formed pressed and punched component of sheet steel or spring steel sheet.

[0065] The adapter component 5 which is optionally provided may, for example, be constructed as a plastics material injection-molded component which can be produced in a favorable manner and which enables particularly simple structural adaptation of a single-piece transmission element 4 according to the invention to different types of steering columns 1 or embodiments of steering shaft switches 2.

[0066] The solution according to the invention is not limited to a steering column which can be adjusted manually in a vertical and/or longitudinal direction. Instead, the solution according to the invention may, for example, also be used with steering columns which can be adjusted in a motorized manner or which are non-adjustable.

TABLE-US-00001 List of reference numerals 1 Steering column 11 Retention unit 12 Side member 13 Actuation unit 14 Cover pipe 15 Steering shaft 151 Portion 152 Securing portion 153 Longitudinal groove 154 Longitudinal groove 155 Auxiliary assembly member 156 Guide channel 16 Longitudinal axis 17 Clamping axle 18 Actuation lever 19 Vertical direction 2 Steering shaft switch 21 Indicator switch 22 Securing opening 23 Counter-portion 24 Carrier element 25 Journal 3 Interface 31 Receiving portion 32 Assembly opening 4 Transmission element 41 Formation 42 Recess 43 Positive-locking element 44 Positive-locking element 45 Centering projection 46 Annular disk 47 Engagement element 48 Securing sleeve 49 Resilient elements 5 Adapter piece 51 Connection opening 52 Locking element