DRIVE ARRANGEMENT HAVING AN ELECTRICAL MACHINE AND A GEAR AND COMPONENTS FOR SUCH A DRIVE ARRANGEMENT

Abstract

The present invention relates to a drive arrangement having an electrical machine and a gear that are in rotational driving connection with each other while forming at least one torque transmission path, wherein at least one element pair consisting of a torque-transmitting first element and a torque-transmitting second element that are in rotational driving connection with each other via a coupling device is arranged in the torque transmission path. The coupling device is designed as a slip clutch, such that the first and second element can be pivoted relative to each other when a pre-determined torque limit value is exceeded. The present invention additionally relates to components for such a drive arrangement.

Claims

1. Drive arrangement having an electrical machine and a gear which are in rotational driving connection with each other while forming at least one torque transmission path, wherein at least one element pair consisting of a torque-transmitting first element and a torque-transmitting second element which are in rotational driving connection with each other via a coupling device is arranged in the torque transmission path, wherein the coupling device is designed as a slip clutch, so that the first and second element can be pivoted relative to each another when a pre-determined torque limit value is exceeded.

2. Drive arrangement according to claim 1, wherein the slip clutch is arranged between the first and second element in the radial direction and preferably has a sleeve-like element arranged between the first and second element while radially pre-tensioned, wherein the sleeve-like element is particularly preferably arranged, with elastic deformation of the latter, between the first and the second element and optionally has elastically deformable radial ledges for this purpose.

3. Drive arrangement according to claim 2, wherein the sleeve-like element has a break in the circumferential direction and/or is made of metal and/or the radial ledges are formed as one part with the sleeve-like element, preferably formed by domes and/or tabs, particularly preferably generated by embossing a base body of the sleeve-like element.

4. Drive arrangement according to claim 1, wherein an element pair is provided, in which the first element is a rotor shaft connected to a rotor of the electrical machine in a manner fixed against rotation and the second element is an output shaft of the electrical machine, wherein the slip clutch is preferably arranged nested with the rotor and/or a stator of the electrical machine in the radial direction and is particularly preferably integrated into the electrical machine and/or is arranged in a housing of the electrical machine, out of which the output shaft optionally protrudes outward.

5. Drive arrangement according to claim 1, wherein an element pair is provided in which the first element is an output shaft of the electrical machine and the second element is an input shaft of the gear, wherein the input shaft of the gear preferably surrounds the output shaft of the electrical machine from outside in the radial direction with the interposition of the slip clutch, and the input shaft of the gear is particularly preferably mounted by way of a radial bearing, optionally a rolling bearing, arranged radially nested with the slip clutch.

6. Drive arrangement according to claim 1, wherein an element pair is provided, in which the first element is a preferably helical gear wheel of the gear and the second element is a gear shaft.

7. Drive arrangement according to claim 1, wherein the gear has a gear wheel which has a first radial section connected to a gear shaft in a manner fixed against rotation, optionally in a form-fit manner and/or not as one part, and a second radial section having a gearing, said radial section being arranged radially nested with the first radial section, wherein the first radial section forms the first element and the second radial section forms the second element of an element pair.

8. Drive arrangement according to claim 1, wherein the gear has an optionally switchable freewheel having a first race, a second race and clamping elements arranged between the first and the second race, wherein an element pair is provided in which the first element is a gear shaft of the gear and the second element is a freewheel hub connected to the first race in a manner fixed against rotation, or in which the first element is a freewheel hub connected to a gear shaft in a manner fixed against rotation, optionally in a form-fit manner and/or not as one part, and the second element is the first race.

9. Drive arrangement according to claim 1, wherein the gear has a gear wheel, arranged on a gear shaft and having a helical gearing and a first straight gearing, and a torque-transmitting sleeve arranged on the gear shaft and having a second straight gearing which is in rotational driving engagement with the first straight gearing, wherein the torque-transmitting sleeve forms the first element and the gear shaft forms the second element of an element pair, the first straight gearing is preferably an outer gearing, while the second straight gearing is an inner gearing, and the gear wheel particularly preferably is or can be supported on the gear shaft in the axial direction via a retaining ring, said retaining ring optionally being or being able to be radially supported on a locking ring and/or the torque-transmitting sleeve while preventing the retaining ring from widening.

10. Component for a drive arrangement according to claim 1 having a torque-transmitting first element and a torque-transmitting second element which are in rotational driving connection with each other via a coupling device, wherein the coupling device is designed as a slip clutch such that the first and second element can be pivoted relative to each another when a pre-determined torque limit value is exceeded, wherein the component is an electrical machine in which the first element is a rotor shaft connected to a rotor of the electrical machine in a manner fixed against rotation and the second element is an output shaft of the electrical machine, wherein the slip clutch is particularly preferably arranged nested with the rotor and/or a stator of the electrical machine in the radial direction and/or is integrated into the electrical machine and/or is arranged in a housing of the electrical machine out of which the output shaft protrudes outward, or a gear wheel, wherein the first element is a first radial section of the gear wheel that can be connected to a gear shaft in a manner fixed against rotation and the second element is a second radial section of the gear wheel having a gearing, arranged radially nested with the first radial section, or an optionally switchable freewheel having a first race, a second race and clamping elements arranged between the races, in which the first element is a freewheel hub that can be connected to a gear shaft in a manner fixed against rotation and the second element is the first race, or a torque-transmitting device that has a gear shaft, a gear wheel arranged on the gear shaft and having a helical gearing and a first straight gearing, and a torque-transmitting sleeve arranged on the gear shaft and having a second straight gearing which is in rotational driving engagement with the first straight gearing, wherein the torque-transmitting sleeve forms the first element and the gear shaft forms the second element.

Description

[0028] The invention is explained in more detail below using exemplary embodiments with reference to the attached drawings. In the following:

[0029] FIG. 1 shows a schematic depiction of an embodiment of the drive arrangement according to the invention for a motor vehicle for or within a motor vehicle,

[0030] FIG. 2 shows a front view of a sleeve-like element in a cut-away depiction,

[0031] FIG. 3 shows a side view of the sleeve-like element from FIG. 2,

[0032] FIG. 4 shows a schematic side view of a first embodiment of an element pair in the drive arrangement according to FIG. 1,

[0033] FIG. 5 shows a partial side view of a second embodiment of an element pair in the drive arrangement according to FIG. 1,

[0034] FIG. 6 shows a partial side view of a third embodiment of an element pair in the drive arrangement according to FIG. 1,

[0035] FIG. 7 shows a partial side view of a fourth embodiment of an element pair in the drive arrangement according to FIG. 1,

[0036] FIG. 8 shows a partial side view of a fifth embodiment of an element pair in the drive arrangement according to FIG. 1, and

[0037] FIG. 9 shows a partial side view of a sixth and seventh embodiment of an element pair in the drive arrangement according to FIG. 1 in a cut-away depiction.

[0038] FIG. 1 shows a schematic depiction of a drive arrangement 2. The drive

[0039] arrangement 2 has an electrical machine 4 such that the drive arrangement 2 can preferably be used in an electric motor vehicle. The electrical machine 4 or its output side is in rotational driving connection with a gear 6 or its input side. By contrast, the output side of the gear 6 is in rotational driving connection with the input side of a differential gear 8, wherein the differential gear 8 is assigned to the two half axles 10, 12 of a vehicle axle of the motor vehicle in a known manner. Although the differential gear 8 is here shown as a differential gear 8 spaced apart from the gear 6, the differential gear 8 can also be assigned to the gear 6 or form a gear section of the gear 6. The electrical machine 4, the gear 6 and the differential gear 8 thus form at least one torque transmission path with one another, via which a torque can be transmitted from the electrical machine 4 to the vehicle axle and vice versa. The gear 6 is preferably designed as a two or multiple speed gear.

[0040] To protect the gear 6, which is designed to be particularly rigid for electric vehicles, and the entire drive arrangement 2 and its components from an overload, at least one mechanical torque limiter is integrated into the drive arrangement 2.

[0041] Generally, at least one element pair 14 consisting of a torque-transmitting first element 16 and a torque-transmitting second element 18 is provided, which elements are in rotational driving connection with each other via a coupling device 20, wherein the first element 16, the second element 18 and the coupling device 20 are arranged in the torque transmission path of the drive arrangement 2. Before the different embodiments of the possible element pairs 14 are explained in more detail, the basic structure of these element pairs 14 will be explained in more detail in the following in connection with the coupling device 20.

[0042] The coupling device 20 is designed as a slip clutch, such that the first and second element 16, 18 can be pivoted relative to each other when a pre-determined torque limit value is exceeded. The coupling device 20 does not couple the first and second elements 16, 18 in a form-fit manner, but rather in a force-fit manner. The slip clutch is arranged between the first element 16 and the second element 18 in the radial direction and has a sleeve-like element 22 arranged radially pre-tensioned between the first and second element 16, 18, as can be understood from FIGS. 4 to 9. To be more precise, the sleeve-like element 22 is arranged, with elastic deformation of the latter, between the first and second element 16, 18, with the sleeve-like element 22 depicted in detail in FIGS. 2 and 3 having elastically deformable radial ledges 24 for this purpose.

[0043] In the depicted embodiment, the radial ledges 24 are formed as one part with the sleeve-like element 22 and formed by domes. It is here preferred if the domes are generated by embossing a base body of the sleeve-like element 22. It has also proved advantageous if the sleeve-like element 22 is made of metal and thus by analogy forms a sheet metal part. As an alternative to the radial ledges 24 in the form of the domes depicted, tabs are also considered as radial ledges, which can be partially stamped and bent out of the base body of the sleeve-like element 22. It is also possible, unlike the depiction in FIGS. 2 and 3, to allow the radial ledges 24 to protrude inward in the radial direction instead of outward in the radial direction as depicted. A break 26 is additionally designed in the sleeve-like element 22, such that the sleeve-like element 22 does not have a continuous course in the circumferential direction, but has a break 26, which is here designed in the form of a longitudinal slit in an advantageous manner.

[0044] In the following, different embodiments of an element pair 14 for the drive arrangement 2 according to FIG. 1 are described with reference to FIGS. 4 to 9, which can also represent components for use in the drive arrangement 2.

[0045] FIG. 4 shows a component for the drive arrangement 2 in the form of the electrical machine 4. The electrical machine 4 has a stator 30 and a rotor 32 within a housing 28. The rotor 32 is connected in a manner fixed against rotation to a rotor shaft 34 that forms the first element 16 of the element pair 14. By contrast, the second element 18 of the element pair 14 is formed by an output shaft 36 of the electrical machine 4 that protrudes outward out of the housing 28 via an opening so that it can be connected to the gear 6. The sleeve-like element 22 is arranged nested both with the rotor 32 and with the stator 30 of the electrical machine 4 in the radial direction, with the slip clutch formed by the sleeve-like element 22 being by analogy integrated into the electrical machine 4 or arranged in the housing 28 of the electrical machine 4.

[0046] As an alternative or in addition to the element pair 14 from FIG. 4, the element pair 14 from FIG. 5 can also be provided in the drive arrangement 2. In the second embodiment according to FIG. 5, the element pair 14 consists of a first element 16 in the form of the output shaft 36 of the electrical machine 4 and the second element 18 in the form of an input shaft 38 of the gear 6, between which elements the sleeve-like element 22 is arranged nested in the radial direction. It is here preferred if the input shaft 38 of the gear 6 surrounds the output shaft 36 of the electrical machine 4 from outside in the radial direction with the interposition of the slip clutch or the sleeve-like element 22, and the input shaft 38 of the gear 6 is further mounted by way of a radial bearing 40 arranged radially nested with the slip clutch. The mounting via the radial bearing 40, which is preferably designed as a rolling bearing, is particularly preferably achieved on a fixed housing or housing section, for example a housing of the gear 6.

[0047] FIG. 6 shows a third embodiment of an element pair 14 in the drive arrangement 2 which can be used as an alternative or in addition to one or several of the element pairs 14 according to FIGS. 4 and 5. In the third embodiment, the element pair 14 is formed by a first element 16 in the form of a helical gear wheel 42 of the gear 6 and a second element 18 in the form of a gear shaft 44, such that the sleeve-like element 22 of the slip clutch is arranged between the gear shaft 44 on the one hand and the gear wheel 42 on the other in the radial direction.

[0048] FIG. 7 shows a fourth embodiment of an element pair 14 for use in the drive arrangement 2 according to FIG. 1 that can be used as an alternative or in addition to the element pairs 14 according to FIGS. 4 to 6. The element pair 14 in the fourth embodiment is formed by a gear wheel 42 of the gear 6, wherein unlike in the embodiment according to FIG. 6, the gear wheel 42 has a first radial section 46 connected to a gear shaft 44 in a manner fixed against rotation and a second radial section 48 having a gearing and arranged radially nested with the first radial section 46. The first radial section 46 forms the first element 16 and the second radial section 48 forms the second element 18 of the element pair 14 such that the sleeve-like element 22 is arranged between the first and the second radial section 46, 48 in the radial direction. This embodiment is preferred to the embodiment according to FIG. 6 in as far as the sleeve-like element 22 can be arranged on a particularly large diameter, whereby a particularly high pre-determined torque limit value can be set. The first radial section 46 itself is preferably fixed to the gear shaft 44 in a manner fixed against rotation in a form-fit and/or force-fit manner, but particularly preferably not formed as one part with the gear shift 44. The gear shaft 44, the first radial section 46 and the second radial section 48 in connection with the sleeve-like element 22 also form a component for use within the drive arrangement 2 according to FIG. 1.

[0049] FIG. 8 shows a further element pair 14 or a further component for use in the drive arrangement 2 according to FIG. 1. The fifth embodiment according to FIG. 8 can find use as an alternative or in addition to the embodiments according to FIGS. 4 to 7 in the drive arrangement 2. According to FIG. 8, the gear 6 has a gear wheel 50 arranged on a gear shaft 44, wherein the gear wheel 50 has a helical gearing 52 and a first straight gearing 54 offset in the axial direction in relation to the helical gearing 52. There is no direct form-fit rotational driving connection between the gear wheel 50 and the gear shaft 44. A torque-transmitting sleeve 56 that has a second straight gearing 58 is additionally arranged on the gear shaft 44. As can be seen from FIG. 8, the first straight gearing 54 is designed as an outer gearing, while the second straight gearing 58 is designed as an inner gearing, wherein the first and second straight gearing 54, 58 are in rotational driving engagement with each other. In this arrangement, the torque-transmitting sleeve 56 forms the first element 16 and the gear shaft 44 forms the second element 18 of the element pair 14, such that an indirect rotational driving connection arises between the gear shaft 44 and the gear wheel 50, i.e., the rotational driving connection between the gear shaft 44 and the gear wheel 50 is made via the sleeve-like element 22 between the gear shaft 44 and the torque-transmitting sleeve 56 and the two straight gearings 54, 58 which are in rotational driving engagement with one another.

[0050] Additionally, the gear wheel 50 is or can be supported on the gear shaft 44 in the axial direction via a retaining ring 60, wherein the retaining ring 60 is or can be supported outward in the radial direction on a locking ring 62 while preventing the retaining ring 60 from widening. Alternatively, the torque-transmitting sleeve 56 can function as a locking ring on which the retaining ring 60 can be or is supported outward in the radial direction such that the separate locking ring 62 is not required.

[0051] The advantage of the embodiment according to FIG. 8 is that tangential forces substantially act on the torque-transmitting sleeve 56, and thus on the sleeve-like element 22, but not axial forces which could act in the axial direction on the gear wheel 50 and thus on the torque-transmitting sleeve 56 and the sleeve-like element 22 due to the helical gearing 52 on the gear wheel 50. This is prevented by the helical gearings 54, 58 and the support of the gear wheel 50 on the retaining ring 60 in the axial direction, however.

[0052] Two further embodiments of an element pair 14 or of a component for the drive arrangement 2 according to FIG. 1 are indicated in FIG. 9. In this embodiment, the gear 6 has a preferably switchable freewheel 64 having a first race 66, a second race 68 and clamping elements 70 arranged between the first and second race 66, 68. The element pair 14 is preferably formed by a first element 16 in the form of a freewheel hub 72 connected to a gear shaft 44 in a manner fixed against rotation and a second element 18 in the form of the first race 66, between which elements the sleeve-like element 22 of the slip clutch is arranged in the radial direction. The freewheel hub 72 is preferably connected to the gear shaft 44 in a form-fit and/or force-fit manner and/or not as one part.

[0053] Regardless, a variant is additionally indicated in FIG. 9 in which the element pair is formed of a first element in the form of the gear shaft 44 and a second element in the form of the freewheel hub 72 connected to the first race 66 in a manner fixed against rotation, wherein here tooanalogously with the previously described embodimentsthe variant with a sleeve-like element 22 arranged further out in the radial direction is preferred so that a particularly high pre-determined torque limit value can be achieved.

List of Reference Numerals

[0054] 2 drive arrangement [0055] 4 electrical machine [0056] 6 gear [0057] 8 differential gear [0058] 10 half axle [0059] 12 half axle [0060] 14 element pair [0061] 16 first element [0062] 18 second element [0063] 20 coupling device [0064] 22 sleeve-like element [0065] 24 radial ledge [0066] 26 break [0067] 28 housing [0068] 30 stator [0069] 32 rotor [0070] 34 rotor shaft [0071] 36 output shaft [0072] 38 input shaft [0073] 40 radial bearing [0074] 42 gear wheel [0075] 44 gear shaft [0076] 46 first radial section [0077] 48 second radial section [0078] 50 gear wheel [0079] 52 helical gearing [0080] 54 first straight gearing [0081] 56 torque-transmitting sleeve [0082] 58 second straight gearing [0083] 60 retaining ring [0084] 62 locking ring [0085] 64 freewheel [0086] 66 first race [0087] 68 second race [0088] 70 clamping element [0089] 72 freewheel hub