Manually disengageable wheel hub for towing and recovering a vehicle

Abstract

The invention relates to a device for torque-decoupling a wheel hub from a drive shaft of a vehicle, in particular a commercial vehicle, having - a driver element (1) with internal toothing (3) that can be permanently connected to the wheel hub; - a drive shaft section (5) with external toothing (7), wherein the external toothing (7) is designed to match the internal toothing (3) in order to be able to transmit torque between the external toothing (7) and the internal toothing (3) when the external toothing (7) and the internal toothing (3) are in contact; and - an operating means (9) designed to bring the internal toothing (3) of the driver element (1) and the external toothing (7) of the drive shaft section (5) into torque-transmitting engagement with one another or to separate them from one another, depending on the setting of the operating means (9).

Description

[0001] Manually detachable wheel hub for towing and recovering a vehicle

[0002] The invention relates to a device for torque decoupling a wheel hub from a drive shaft of a vehicle.

[0003] When towing a broken-down vehicle, it is important to ensure that no other components are damaged or people are injured during the towing process. Especially with battery-electric vehicles, it may be necessary to tow a vehicle more often if the battery is discharged.

[0004] In conventional vehicles, the drive shaft is typically either separated from the axle and secured to the chassis with tensioning straps or something similar to prevent it from dragging on the road. This requires someone to crawl under the vehicle. Or, the axle shafts are pulled out. This does not require someone to crawl under the vehicle, but there is no guarantee that the axle shafts (which are often around 70 cm long) can be pulled out safely. If the vehicle is parked on the side of the road, the guardrail on one side can be in the way and the flow of traffic can be disrupted on the other. In addition, a considerable amount of axle oil typically leaks out, and caps are needed to seal the wheel hubs.

[0005] DE 102021 118 755 A1 relates in a broader context to an autonomously driving commercial vehicle, comprising at least one interface for connecting to a, preferably peripheral, emergency control unit; wherein the interface is configured to receive control signals from the emergency control unit; and wherein the commercial vehicle is configured to be controllable in an emergency driving mode based on the control signals received from the emergency control unit.

[0006] The object of the invention is to simplify the towing and recovery of a vehicle. The invention is characterized by the features of the independent claims. Advantageous further developments and refinements are the subject of the dependent claims.

[0007] A first aspect of the invention relates to a device for torque decoupling of a wheel hub from a drive shaft of a vehicle, in particular a commercial vehicle, comprising

[0008] - a driving element with internal teeth that can be permanently connected to the wheel hub;

[0009] - a drive shaft section with external teeth, wherein the external teeth are designed to match the internal teeth in order to be able to transmit a torque between the external teeth and the internal teeth when the external teeth and the internal teeth are connected; and

[0010] - an operating means which is designed to bring the internal toothing of the driver element and the external toothing of the drive shaft section into torque-transmitting engagement with one another or to separate them from one another, depending on the setting of the operating means.

[0011] The drive shaft section is part of the drive shaft and can be designed as a single piece with the rest of the drive shaft, or in the case of a two-piece design of the drive shaft section and the rest of the drive shaft, both parts can be permanently connected to each other in a torque-resistant manner.

[0012] The operating means allows, in particular by manually performed settings, the internal toothing of the driver element and the external toothing of the drive shaft section to be selectively engaged with one another or disengaged from one another, so that no torque can be transmitted from the drive shaft to the wheel hub and vice versa.

[0013] One advantageous effect of the invention is that the drive train can be quickly and safely coupled and uncoupled at the wheel with relatively little effort. Operating the operating device also eliminates the need for the user to intervene underneath the vehicle. All parts required for reversible torque decoupling remain on the vehicle; at most, standard tools may be required to make the desired adjustment to the operating device. However, an adjusting screw of the same size and shape as the wheel nuts can also be provided on the operating device, so that torque decoupling can be easily performed if a suitable tool for the wheel nuts is carried in the vehicle or in a support vehicle such as a tow truck. There is no risk of operating fluids leaking out during torque decoupling.

[0014] According to an advantageous embodiment, the driver element is annular and coaxially surrounds the drive shaft section when the external toothing and internal toothing are connected, wherein the internal toothing is designed over a complete circumference.

[0015] According to a further advantageous embodiment, the operating means is a pulling element with a cylinder head screw, wherein the cylinder head screw is screwed into the end face of the drive shaft section on the one hand and is rotatably held on the driver element on the other hand.

[0016] According to a further advantageous embodiment, the tension element has a support screw which can be screwed into a cover of the driver element and which carries a ball bearing at its free shaft end, on which the cylinder head screw is rotatably mounted and held axially immovably.

[0017] According to a further advantageous embodiment, the support screw is designed as a hollow screw in which the ball bearing is accommodated in an annular recess, wherein the head of the cylinder head screw is supported on an end of the ball bearing facing away from the shaft.

[0018] According to a further advantageous embodiment, the operating means has a closure part which is inserted into the through-bore of the hollow screw and seals it.

[0019] According to a further advantageous embodiment, the closure part is designed as a screw which carries a sealing ring on the underside of the head and is screwed into an internal thread of the hollow screw.

[0020] According to a further advantageous embodiment, the closure part is designed as an elastic plug that is pressed into the through-bore of the hollow screw and preferably has a handle on its end face for removing the plug from the through-bore. According to a further advantageous embodiment, an annular seal is arranged on the underside of a head of the hollow screw, with which the hollow screw is sealingly supported against the outside of the cover of the driver element.

[0021] According to a further advantageous embodiment, the driver element is designed in two parts and has an annular base part provided with the internal toothing and a cover part which is detachably fastened, in particular screwed, to this base part and which, together with the end face of the drive shaft section, delimits a shaft release space.

[0022] Further advantages, features, and details will become apparent from the following description, which – where appropriate with reference to the drawings – describes at least one embodiment in detail. Identical, similar, and / or functionally equivalent parts are provided with the same reference numerals.

[0023] They show:

[0024] Fig. 1: A sectional drawing of a device for torque decoupling a wheel hub from a drive shaft of a vehicle according to an embodiment of the invention in the coupled state.

[0025] Fig. 2: The device for torque decoupling a wheel hub from a drive shaft of a vehicle according to Fig. 1, but in the decoupled state.

[0026] Fig. 3: Schematic parts of the device according to Fig. 1 and Fig. 2.

[0027] Fig. 4: A support screw of the operating means according to an embodiment of the invention for a device as shown in Fig. 1 to Fig. 2.

[0028] The representations in the figures are schematic and not to scale.

[0029] Fig. 1 shows a cross-sectional view of a device for decoupling the torque of a wheel hub from a drive shaft of an electric vehicle when the vehicle is to be towed. The hatched areas indicate that this is a cross-sectional view of the individual components. In Fig. 1 as well as in Fig. 2, the drawings are aligned such that, in the plane of the drawing, from the left, the wheel can be placed onto the still visible wheel hub, and to the right, the drive shaft runs into the vehicle. The device has a driver element 1 that can be permanently connected to the wheel hub, wherein the driver element 1 has internal teeth 3 that are not visible in Fig. 1 (see Fig. 3), since in Fig. 1 the internal teeth 3 engage with external teeth 7 of a drive shaft section 5 of the device.The drive shaft section 5 is radially raised relative to the rest of the vehicle's drive shaft so that the radii of the external gearing 7 and the internal gearing 3 (see Fig. 3) are coordinated and can be engaged with one another in order to transmit torque from the drive shaft to the wheel hub. This is the case during normal operation of the vehicle and in the position of the parts in Fig. 1. The drive shaft with the drive shaft section 5 is not screwed to the wheel hub for this purpose, but engages on the wheel side in a spline toothing created by intermeshing internal gearing 3 and external gearing 5 for normal operation of the vehicle. In this example, the cover 19 and driver element 1 are designed in two parts, positioned relative to one another via locating pins and fixed together with countersunk screws.This solution takes into account the fact that the internal toothing 3 in the driver element 1 must be heat-treated, which results in different material requirements than for the cover 19. A one-piece variant would also be feasible, but the production of the toothing is more complex. The cover 19 has a number of through-openings distributed around the circumference in an edge region of its front side, through which it can be screwed to the wheel hub using screws. The base part has first through-openings in this regard, which, when screwed, are aligned with the through-openings in the cover part. In addition, the base part has second through-openings through which the base part can be screwed to the cover part, with the corresponding screws inserting into blind screw holes in the cover 19.

[0030] In Fig. 2, however, the driver element 1 is shifted relative to the drive shaft section 5 such that the external toothing 7 of the drive shaft section 5 no longer engages with the internal toothing 3 of the driver element 1. This shift is effected by an operating means 9 which penetrates a cover 19. The operating means 9 can be operated manually by a user from the outside, i.e. from the wheel side, and for this purpose has a carrier screw 13 (cf. Fig. 4). A hexagon head of the hollow screw has the same wrench size as the wheel nuts; this ensures that no additional on-board tools are required. The use of the hollow screw has the advantage that it is accessible from the outside and can be unscrewed using on-board tools far enough to break the force-locking connection between the drive shaft and the wheel hub.

[0031] Fig. 3 shows a schematic exploded view of cover 19, driver element 1 with internal toothing 3, and drive shaft section 5 with external toothing 7. The driver element 1 is annular and coaxially surrounds the drive shaft section 5 when the external toothing 7 and internal toothing 3 are connected, wherein the internal toothing 3 and the external toothing 7 are designed over a respective complete circumference.

[0032] Fig. 4 shows the operating means 9 in more detail, inserted into a recess in the cover 19. The carrier screw 13 is designed as a hollow screw, which has a locking screw as the closure part 17. The locking screw is inserted into a through-hole in the hollow screw and closes it, sealing it. For this purpose, a sealing ring is arranged on the underside of a head of the locking screw and screwed into an internal thread of the hollow screw. This locking screw in the hollow screw simplifies assembly: A bearing is mounted in the hollow screw with an auxiliary retaining ring, the driver element 1 and cover 19 are screwed together, the hollow screw with the sealing ring is screwed in, and the auxiliary retaining ring is installed.The drive shaft can then be screwed to the drive shaft section 5 using a cylinder head screw 11 and a spacer sleeve (depending on the design of the drive shaft at this point, this can also be omitted), and the hollow screw is closed with a locking screw and sealing ring. The cylinder head screw 11 is thus screwed into the end face of the drive shaft section 5 on the one hand, and is also rotatably held on the driver element 1 by means of the deep groove ball bearing 15. For this purpose, the ball bearing 15 is received in an axially immovable manner in an annular recess in the hollow screw (support screw 13), with the head of the cylinder head screw 11 resting on an end of the ball bearing 15 facing away from the shaft. An annular seal is also arranged on the underside of a head of the hollow screw, with which the hollow screw is sealingly supported on the outside of the cover 19 of the driver element 1.A sealing ring between the support screw 13 and the cover 19 is preferably made of elastomer. If it needs to be replaced due to aging, it can be pulled over the hexagon of the hollow screw. Using a metal sealing ring would require the cover 19 to be removed.

[0033] This allows two states to be set: a) Drive state: The hollow screw holds the drive shaft section 5 of the drive shaft in the axial direction via the deep groove ball bearing 15. The drive shaft section 5 of the drive shaft engages the internal toothing 3 of the driver element 1, thus transmitting the torque from the vehicle's differential to the wheel hub. b) Axle shaft decoupled:

[0034] The banjo bolt is unscrewed until the locking ring 21 (visible on the outside of the banjo bolt in Fig. 4, axially between ball bearing 15 and cover 19) rests on the inside of the cover 19. The drive shaft is pulled out of the driver element 1 via the deep groove ball bearing 15 and fixed in this position. The drive shaft can now rotate freely and no torque is transferred from the differential to the wheel hub. While the drive shaft is completely disengaged from the toothing 3 of the driver element 1 during uncoupling and can therefore no longer exert any torque on the wheel hub, the drive shaft remains at the other end with a section in the toothing of the respective axle shaft gear and is thus still held in the transmission.

[0035] Although the invention has been illustrated and explained in detail by preferred embodiments, the invention is not limited by the disclosed examples, and other variations may be derived therefrom by those skilled in the art without departing from the scope of the invention. It is therefore clear that a multitude of variations exist. It is also clear that exemplary embodiments are truly only examples and should not be construed as limiting the scope, possible applications, or configuration of the invention in any way.Rather, the preceding description and the description of the figures enable the person skilled in the art to implement the exemplary embodiments in concrete terms. With knowledge of the disclosed inventive concept, the person skilled in the art can make various changes, for example, with regard to the function or arrangement of individual elements mentioned in an exemplary embodiment, without departing from the scope of protection defined by the claims and their legal equivalents, such as further explanations in the description. List of reference symbols.

[0036] 1 driver element

[0037] 3 Internal gearing

[0038] 5 Drive shaft section

[0039] 7 External gearing

[0040] 9 Controls

[0041] 11 cylinder head screw

[0042] 13 support screw

[0043] 15 ball bearings

[0044] 17 Locking part

[0045] 19 lids

[0046] 21 Retaining ring

Claims

Patent claims 1. Device for torque decoupling of a wheel hub from a drive shaft of a vehicle, comprising - a driver element (1) with an internal toothing (3) that can be permanently connected to the wheel hub; - a drive shaft section (5) with an external toothing (7), wherein the external toothing (7) is designed to match the internal toothing (3) in order to be able to transmit a torque between the external toothing (7) and the internal toothing (3) when the external toothing (7) and the internal toothing (3) are connected; and - an operating means (9) which is designed to bring the internal toothing (3) of the driver element (1) and the external toothing (7) of the drive shaft section (5) into torque-transmitting engagement with one another or to separate them from one another, depending on the setting of the operating means (9).

2. Device according to claim 1, wherein the driver element (1) is annular and coaxially surrounds the drive shaft section (5) when the external toothing (7) and internal toothing (3) are connected, wherein the internal toothing (3) is designed over a complete circumference.

3. Device according to one of the preceding claims, wherein the operating means (9) is a pulling element with a cylinder head screw (11), wherein the cylinder head screw (11) is screwed into the end face of the drive shaft section (5) on the one hand and is rotatably held on the driver element (1) on the other hand.

4. Device according to claim 3, wherein the tension element comprises a support screw (13) which is inserted into a cover (19) of the driver element (1) and carries a ball bearing (15) at its free shaft end, on which the cylinder head screw (11) is rotatably mounted and held axially immovably.

5. Device according to claim 4, wherein the support screw (13) is designed as a hollow screw in which the ball bearing (15) is received in an annular recess, wherein the head of the cylinder head screw (11) is supported on an end of the ball bearing (15) facing away from the shaft.

6. Device according to claim 5, wherein the operating means (9) has a closure part (17) which is inserted into the through-bore of the hollow screw and seals it.

7. Device according to claim 6, wherein the closure part (17) is designed as a screw which carries a sealing ring on the underside of the head and is screwed into an internal thread of the hollow screw.

8. Device according to claim 6, wherein the closure part (17) is designed as an elastic plug which is pressed into the through-bore of the hollow screw.

9. Device according to one of claims 5 to 8, wherein an annular seal is arranged on the underside of a head of the hollow screw, with which the hollow screw is sealingly supported on the outside of the cover (19) of the driver element (1).

10. Device according to one of the preceding claims, wherein the driver element (1) is formed in two parts and has an annular base part provided with the internal toothing (3) and a cover (19) detachably fastened, in particular screwed, to this base part, which delimits a shaft release space with the end face of the drive shaft section (5).

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