Friction clutch of multi-speed transmission and electric drive of vehicle

Abstract

The invention provides a friction clutch of a multi-speed transmission and an electric drive of a vehicle. A friction clutch of a multi-speed transmission (10) comprises: an actuation sleeve (26) seated on a shaft (18) and adapted to move linearly along the shaft (18); a first friction clutch unit (30) arranged on one side of the actuating sleeve (26) in the axial direction; a second friction clutch unit (34) arranged in the axial direction on a side of the actuating sleeve (26) opposite the first friction clutch unit (30), the actuating sleeve (26) generating a friction fit in the first friction clutch unit (30) in a first engaged state and generating a friction fit in the second friction clutch unit (34) in a second engaged state. An electric drive of a vehicle has a two-stage transmission and an electric motor coupled via a friction clutch (22) according to the invention.

Description

Technical Field

[0001] The invention relates to a friction clutch of a multi-speed transmission and an electric drive of a vehicle. Background Art

[0002] Multi-speed transmissions are increasingly being used in electric drives, in particular for the purpose of increasing efficiency.

[0003] An important requirement is to shift gears without load interruption. For this purpose, the previous prior art usually provides a double clutch, each having a clutch and an actuator assigned to the clutch for actuating the clutch.

[0004] However, this design is expensive to manufacture, complex, requires more space, and is heavy, especially due to the presence of two actuators.

[0005] Furthermore, a dual clutch transmission requires precise control of the actuators so that the clutches are opened or closed in precise synchronization with each other. Summary of the invention

[0006] Against this background, it is an object of the present invention to provide a clutch which enables gear shifting without load interruption and which at the same time can be produced cost-effectively and can be controlled in a simple and reliable manner.

[0007] The object is achieved by a friction clutch of a multi-stage transmission, the friction clutch comprising: an actuating sleeve, the actuating sleeve being seated on a shaft and being adapted to move linearly along the shaft between a first engagement state and a second engagement state; a first friction clutch unit, the first friction clutch unit being arranged on one side of the actuating sleeve in an axial direction and comprising a first clutch body, the first clutch body being rotatably mounted on the shaft; a second friction clutch unit, the second friction clutch unit being arranged on the side of the actuating sleeve opposite to the first friction clutch unit in an axial direction and comprising a second clutch body, the second clutch body being rotatably mounted on the shaft; a first spring unit, which is axially arranged between the actuating sleeve and the first friction clutch unit; a second spring unit, which is axially arranged between the actuating sleeve and the second friction clutch unit, the spring units axially prestressing the two friction clutch units when the actuating sleeve is in a neutral position, the actuating sleeve in a first engaged state producing a friction fit in the first friction clutch unit and thus a rotational connection between the shaft and the first clutch body, and the actuating sleeve in a second engaged state producing a friction fit in the second friction clutch unit and thus a rotational connection between the shaft and the second clutch body.

[0008] The basic idea of ​​the invention is to achieve a gear change without load interruption by moving the actuating sleeve from one engaged state via a neutral position into the other engaged state, so that the friction fit in one friction clutch unit is released and then the friction fit in the other friction clutch unit is immediately generated by a smooth transition.

[0009] This has the advantage that no coordination is required when one of the friction clutch units is opened and the other friction clutch unit is closed, since this is automatically controlled by moving the actuating sleeve.

[0010] Furthermore, the design according to the invention allows a particularly space-saving clutch to be realized, since only one actuator is required to move the actuating sleeve.

[0011] In one aspect, it is provided that the actuating sleeve has, at least on a side facing the friction clutch unit, an axial bearing assigned thereto, on which the corresponding elastic spring unit is supported in the axial direction.

[0012] This ensures that in the event of a speed difference between the actuating sleeve and the clutch body, no friction is generated or reduced which would lead to wear of the actuating sleeve, the spring unit or the friction clutch.

[0013] The axial bearing can be a needle roller bearing or a plain bearing which comprises a sliding disk, in particular a coated sliding disk.

[0014] If the axial bearing is designed as a needle roller bearing, this can provide a particularly robust and cost-effective axial bearing.

[0015] If the axial bearing is a sliding bearing, the space requirement of the axial bearing, in particular in the axial direction, is particularly low, so that the friction clutch itself can also be designed to be more compact.

[0016] Alternatively, additional bearings or sliding rings can be omitted by appropriately coating and / or hardening the components between which relative speeds may occur. In this alternative, the sliding bearing or roller bearing is thus formed by coating and / or hardening the contact components themselves.

[0017] Thus, for example, the actuating sleeve and / or the clutch body and / or the spring unit and / or the friction clutch can be coated and / or hardened.

[0018] Furthermore, in the neutral position of the actuating sleeve, at least approximately the same axial forces may act on the first friction clutch unit and the second friction clutch unit, respectively, which is caused by the associated first spring unit or second spring unit, which is respectively prestressed, located between the actuating sleeve and the first friction clutch unit or the second friction clutch unit.

[0019] On the one hand, this ensures that the actuating sleeve automatically assumes the neutral position without external forces, since the first spring unit and the second spring unit are also axially supported on the actuating sleeve.

[0020] On the other hand, the axial force acting on the first friction clutch unit or the second friction clutch unit via the first spring unit and the second spring unit in the neutral position can be selected such that even a slight movement of the actuating sleeve results in a friction fit in one friction clutch unit, which allows at least a certain minimum torque (of the drive) or also a maximum possible torque to be transmitted, without any friction fit no longer existing in the other friction clutch unit.

[0021] It can thus be ensured that the gear change can be performed almost instantaneously and at least approximately without load interruption when the actuating sleeve is moved from one engaged state to the other engaged state.

[0022] In addition, when the actuating sleeve is axially moved to the first engagement state, the magnitude of the axial force acting on the second friction clutch unit can be zero or reduced compared to the neutral position. Alternatively or additionally, when the actuating sleeve is axially moved to the second engagement state, the magnitude of the axial force acting on the first friction clutch unit can be zero or reduced compared to the neutral position.

[0023] It is particularly advantageous if the magnitude of the axial force drops to zero, since the friction in the non-actuated friction clutch unit due to the speed difference in the friction clutch can be reduced to a minimum, so that wear can also be reduced.

[0024] Any wear that may occur due to speed differences in the corresponding friction clutches can be reduced at least to a certain extent if the corresponding axial forces are at least reduced compared to the neutral position when the actuating sleeve is axially moved into engagement. However, since the neutral position hardly occurs in time, this wear can be ignored.

[0025] Furthermore, the first clutch body and / or the second clutch body may be coupled to the gear for common rotation therewith.

[0026] When the friction clutch is closed, the torque is automatically transferred from the shaft via the clutch body to the gear coupled to the clutch body. The direct coupling of the clutch body and the gear also enables a space-saving design.

[0027] The first friction clutch unit and / or the second friction clutch unit may comprise a multi-disk clutch.

[0028] Multi-disk clutches are particularly suitable for transmitting high torques, have low wear and require only a small amount of space in the axial direction.

[0029] The respective multi-disc clutch may have an outer disk carrier, which is formed by the respective clutch body or is coupled to the respective clutch body for co-rotation therewith. Furthermore, an outer disk and an inner disk may be arranged within the outer disk carrier, the outer disk being coupled to the outer disk carrier for co-rotation therewith, and the inner disk being coupled to the shaft for co-rotation therewith.

[0030] In the case where the outer plate carrier corresponds to the clutch body, the clutch body simultaneously assumes multiple tasks, so that no additional clutch body is required. This saves costs and installation space.

[0031] Furthermore, the outer disk of a corresponding multi-disk clutch can be provided with friction linings on both sides, and the inner disk can be a steel disk.

[0032] Furthermore, it is in particular possible that the disc package ends with an inner disc towards the actuating sleeve.

[0033] If there is no friction fit in the friction clutch unit, there may be a speed difference between the shaft and the outer disc carrier.

[0034] This also results in a speed difference between the outer disc coupled to the outer disc carrier and the inner disc coupled to the shaft.

[0035] Since the actuating sleeve is arranged on the shaft and can be connected to the shaft for co-rotation with the shaft, for example the actuating sleeve and also the elastic spring unit have the velocity of the shaft.

[0036] In order to minimize wear at the contact points between the friction clutch unit designed as a multi-disk clutch and the actuating sleeve or its elastic spring unit, it is advantageous if the disk package ends with an inner disk toward the actuating sleeve, since the inner disk has the same speed as the shaft.

[0037] Furthermore, it is advantageous if the disk package ends with a steel disk, here an inner disk, since the steel disk allows the axial forces acting from the actuating sleeve via the spring unit on the friction clutch unit to be introduced into the multi-disk clutch in a particularly uniform and planar manner.

[0038] This produces a uniform surface pressure and thus ensures a reliable friction fit when the actuating sleeve engages. In addition, any wear that may occur on the discs of the multi-disc clutch occurs evenly.

[0039] Furthermore, the first friction clutch unit and / or the second friction clutch unit may comprise a cone clutch.

[0040] The friction clutch unit may thus have a multi-disk clutch or a cone clutch or even a friction clutch and a cone clutch.

[0041] The advantage of a cone clutch is that particularly low actuation and holding forces can already be achieved due to the friction fit due to the cone angle. Therefore, lower axial forces are required compared to a multi-disk clutch.

[0042] Furthermore, it is also possible that, in the friction clutch, one friction clutch unit comprises a cone clutch and the other friction clutch unit comprises a multi-disk clutch.

[0043] For example, a multi-plate clutch may be used in a friction clutch that has to transmit a relatively high torque, whereas a cone clutch may be used in a friction clutch that has to transmit a relatively low torque.

[0044] Alternatively, the reverse is also possible, for example in the case of high friction power or limited friction energy.

[0045] If only identical friction clutch units, ie two multi-disk clutches or two cone clutches, are used in the friction clutch, this simplifies production and assembly.

[0046] Furthermore, a larger number of identical parts can reduce production costs.

[0047] The respective cone clutch may have an outer cone friction ring carrier coupled to the shaft for common rotation therewith and formed by the respective clutch body.

[0048] When the outer conical friction ring carrier corresponds to the clutch body, the clutch body simultaneously undertakes multiple tasks, so that there is no need to set up an additional clutch body, thereby saving costs and installation space.

[0049] Furthermore, at least one first conical friction ring element and at least one second conical friction ring element may be at least partially arranged within the outer conical friction ring carrier, the first conical friction ring element being coupled to the outer conical friction ring carrier for rotation therewith, and the second conical friction ring element being coupled to the shaft for rotation therewith, in particular, wherein the outer conical friction ring carrier has an inner conical surface against which the second conical friction ring element can rest, the second conical friction ring element being located between the outer conical friction ring carrier and the first conical friction ring element.

[0050] This arrangement allows a space-saving design of the cone clutch.

[0051] Furthermore, a plurality of friction surfaces may be provided, such that the cone clutch is suitable for transmitting higher torques than would be the case if only an outer conical friction ring carrier and a single conical friction ring element were provided.

[0052] Furthermore, the corresponding cone clutch may include a first cone friction ring element and two cone friction ring elements, the first cone friction ring element is located between the two cone friction ring elements, and the two cone friction ring elements each have a friction surface facing the first cone friction ring element.

[0053] This design allows the cone clutch to transmit higher torques than if it had only an outer conical friction ring carrier and a single conical friction ring element, as described above.

[0054] In addition, one of the second conical friction ring elements, which is coupled to the shaft for common rotation therewith, forms an axial end of the cone clutch toward the elastic spring unit.

[0055] The corresponding elastic spring unit can be supported on the radially innermost conical friction ring element.

[0056] If the radially innermost conical friction ring element is the second conical friction ring element, as described above, there is no speed difference with the elastic spring element, so there is no friction between the components and therefore no wear.

[0057] The first elastic spring unit and / or the elastic spring unit may comprise at least one wave ring, a spring or a combination of these elements.

[0058] Both disc springs and wave springs are particularly suitable for this purpose because when they are prestressed or compressed they apply an axial force to the friction clutch evenly along the entire circumference.

[0059] Furthermore, disc springs and wave springs are particularly cost-effective components.

[0060] Additionally, the actuation sleeve may be disposed on the shaft for common rotation therewith.

[0061] Alternatively, the actuating sleeve may be rotatably mounted on the shaft.

[0062] In case the actuating sleeve is arranged on the shaft for common rotation therewith, the friction clutch unit can be designed such that the actuating sleeve always applies an axial force via the spring unit to a portion of the friction clutch unit which is also coupled to the shaft for common rotation therewith so as not to generate a relative speed.

[0063] In the case of an actuating sleeve which is rotatably mounted on the shaft, the actuating sleeve can adopt the speed of the respective friction clutch when one of the friction clutches is actuated, thereby adjusting the speed in the event of a possible speed difference.

[0064] The actuation sleeve may be coupled to an electromechanical actuator or a hydraulic actuator or an electromagnetic actuator or a ball ramp actuator for actuation.

[0065] The electromechanical actuator allows precise movement and actuation of the actuation sleeve.

[0066] A particularly rapid displacement of the actuating sleeve can be achieved by means of a hydraulic actuator or an electromagnetic actuator.

[0067] By means of the ball ramp actuator, it is also possible to adjust particularly precisely to what extent the actuating sleeve is moved, wherein in this case the actuating sleeve itself can be designed in multiple parts.

[0068] The object mentioned at the outset is also achieved by an electric drive for a vehicle having a 2-speed transmission and an electric motor coupled via a friction clutch according to the invention.

[0069] The resulting advantages can be found in the above paragraphs. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] The invention will now be described with reference to one embodiment shown in the accompanying drawings, in which:

[0071] Figure 1 A schematic diagram of an electric drive according to the invention for a vehicle having a multi-speed transmission with a friction clutch according to the invention is shown;

[0072] Figure 2 shows a sectional view of a friction clutch according to the invention with a friction clutch unit according to a first alternative;

[0073] Figure 3 shows a sectional view of a friction clutch according to the invention with a friction clutch unit according to a second alternative;

[0074] Figure 4 shows a sectional view of a friction clutch according to the invention with a friction clutch unit according to a third alternative;

[0075] Figure 5 shows a cross-sectional view of a friction clutch according to the invention with an actuator according to a first option; and

[0076] Figure 6 A sectional view of a friction clutch according to the invention with an actuator according to a second option is shown. DETAILED DESCRIPTION

[0077] Among other things, Figure 1 An electric drive of a vehicle is shown, which has a multi-step transmission 10 for an electric motor 12 of the vehicle, which is designed as a two-step transmission.

[0078] The multi-speed transmission 10 has an input shaft 14 which is coupled to an electric motor 12 and which is coupled via a gear 16 to a gear 20 arranged on a shaft 18 .

[0079] Furthermore, a friction clutch 22 is arranged on the shaft 18 , by means of which it can be determined which of the gear stages formed by the gearwheels 16 and 20 is engaged.

[0080] The shaft 18 is in turn connected to an output shaft 24 via further gears.

[0081] In the following, reference will be made to Figure 2 The structure of the friction clutch 22 is explained in more detail.

[0082] The friction clutch 22 has an actuating sleeve 26 which is seated on the shaft 18 and can be moved linearly along the shaft 18 .

[0083] The actuating sleeve 26 may be disposed on the shaft 10 for co-rotation with the shaft 10, such as Figure 2 The situation in.

[0084] Alternatively, the actuating sleeve 26 can also be rotatably mounted on the shaft 18 .

[0085] An actuator 28 , which will be discussed in greater detail below, is provided to move the actuation sleeve 26 .

[0086] In addition, the friction clutch 22 includes a first friction clutch unit 30 which is arranged at one side of the actuating sleeve 26 in the axial direction and a first spring unit 32 which is axially disposed between the actuating sleeve 26 and the first friction clutch unit 30 .

[0087] The first friction clutch unit 30 has a first clutch body 33 which is rotatably mounted on the shaft 18 and is coupled to one of the gears 20 for common rotation therewith.

[0088] The friction clutch further comprises a second friction clutch unit 34 which is arranged on the side of the actuating sleeve 26 opposite to the first friction clutch unit 30 in the axial direction and a second spring unit 36 ​​which is axially disposed between the actuating sleeve 26 and the second friction clutch unit 34 .

[0089] The second friction clutch unit 34 has a second clutch body 38 which is also rotatably mounted on the shaft 18 and is coupled to the other of the two gears 20 for common rotation therewith.

[0090] The first spring unit 32 and the second spring unit 36 ​​may include a wave ring or a coil spring or a wave ring group or a coil spring group.

[0091] Figure 2 The friction clutch 22 shown in FIG. 1 corresponds to a first alternative, wherein the first friction clutch unit 30 and the second friction clutch unit 34 each comprise a multi-disk clutch 40 .

[0092] Each of the multi-disk clutches 40 has an outer disk carrier 42 which is formed by the respective clutch body 33 , 38 .

[0093] Alternatively, a separate outer plate carrier may also be provided which is respectively coupled to the clutch bodies 33 , 38 .

[0094] The outer disk 44 is correspondingly disposed within the outer disk carrier 42 and coupled to the outer disk carrier 42 for common rotation therewith.

[0095] Furthermore, an inner disc 46 coupled to the shaft 18 for common rotation therewith is disposed within each outer disc carrier 42 .

[0096] The inner disk 46 of the corresponding multi-disk clutch 40 has friction linings 48 on both sides, while the outer disk 44 is designed as a steel disk. This can also be designed in reverse.

[0097] There is also an axial bearing 50. The axial bearing 50 can be designed as a needle bearing 52 (see Figure 2 , the right side of the actuating sleeve 26) or can also be designed as a sliding bearing 54 with a sliding disk 56 (see Figure 2 , the left side of the actuating sleeve 26).

[0098] Alternatively, additional bearings or sliding rings can be omitted by appropriately coating and / or hardening the contact parts between which relative speeds may exist. For example, needle bearings 52 can therefore be omitted. In this alternative, the sliding bearing is therefore formed by coating and / or hardening of the parts themselves.

[0099] This allows the spring units 32, 36 to be supported on the respective axial bearings 50 and on axially opposite sides of the outer disk 44, as in Figure 2In the event of a speed difference between the actuating sleeve 26 and the outer disc carrier 42 and thus also the outer disc 44 , the axial bearing 50 allows the spring units 32 , 36 to move together with the actuating sleeve 26 .

[0100] This can prevent or at least reduce friction and thus also wear.

[0101] Alternatively, the inner disk 46 can also be designed as a steel disk, and the outer disk 44 can be provided with a friction lining 48. In this design, the disk package formed by the outer disk 44 and the inner disk 46 advantageously ends with the inner disk 46 facing the actuating sleeve 26 ( Figure 2 not shown).

[0102] It is thus ensured that the spring units 32, 36 are not affected by any relative speed if the actuating sleeve 26 is connected to the shaft 18 to rotate with the shaft 18 towards the multi-disc clutch, since the inner disk 46 is coupled to the shaft 18 like the actuating sleeve 26. An axial bearing is therefore not necessary in this design.

[0103] The following will refer to Figure 2 The movement of the friction clutch 22 by means of the actuating sleeve 26 is discussed.

[0104] exist Figure 2 In the embodiment of the present invention, the actuating sleeve 26 is in the neutral position.

[0105] In the neutral position of the actuating sleeve 26 , the two spring units 32 , 36 of the friction clutch units 30 , 34 are axially prestressed, so that an axial force acts on each of the multi-disk clutches 40 .

[0106] In the neutral position of the actuating sleeve 26 , due to the prestressed first spring unit 32 and second spring unit 36 ​​, axial forces of at least approximately the same magnitude act on the first friction clutch unit 30 and the second friction clutch unit 34 , respectively.

[0107] Starting from the neutral position, the actuating sleeve 26 can be moved towards the first friction clutch unit 30 (to the right) into a first engaged state.

[0108] This produces a friction fit in the first friction clutch unit 30 , so that there is a rotational connection between the shaft 18 and the first clutch body 33 , and therefore also between the shaft 18 and the gearwheel 20 .

[0109] When the actuating sleeve 26 is axially moved from the neutral position toward the first friction clutch unit 30 to the first engaged state, the magnitude of the axial force acting on the second friction clutch unit 34 is zero or at least reduced compared to the neutral position.

[0110] Therefore, when the actuating sleeve 26 is in the first engaged state, there is as little friction as possible in the second friction clutch unit 34 .

[0111] Furthermore, the actuating sleeve 26 can also be moved from the neutral position towards the second friction clutch unit 34 (to the left) into a second engaged state.

[0112] As a result, a friction fit is produced in the second friction clutch unit 34 , so that there is a rotational connection between the shaft 18 and the second clutch body 38 , and thus also between the shaft 18 and the gearwheel 20 .

[0113] Here too, in the case of the axial movement of the actuating sleeve 26 into the second engaged state, the amount of the axial force acting on the first friction clutch unit 30 is zero or is at least reduced compared to the neutral position.

[0114] As already explained with respect to the second friction clutch unit 34 , this applies in the first friction clutch unit in that as little friction as possible is generated in the first friction clutch unit 30 when the actuating sleeve 26 is in the second engaged state.

[0115] Furthermore, since movement of the actuating sleeve 26 causes the friction fit in one friction clutch unit to be released and actually immediately creates a friction fit in the other friction clutch unit, a "smooth" transition is achieved when the actuating sleeve moves from one engaged state to the other.

[0116] This allows "shifting" between gear stages without load interruption.

[0117] Figure 3 A friction clutch 22 is shown with friction clutch units 30 , 34 according to a second alternative.

[0118] and Figure 2 In contrast to the friction clutch 22 shown in FIG. 5 , the first friction clutch unit 30 and the second friction clutch unit 34 each have a cone clutch 58 .

[0119] Both cone clutches 58 comprise an outer cone friction ring carrier 60 which simultaneously forms the respective clutch body 33, 38. The outer cone friction ring carrier 60 is formed with a conical, radially inwardly directed friction surface (inner cone surface 66) which can be used for torque transmission.

[0120] Arranged within the outer conical friction ring carrier 60 of the cone clutch 58 is a first conical friction ring element 62 which is coupled to the outer conical friction ring carrier 60 for common rotation therewith.

[0121] Additionally, a second conical friction ring element 62 is provided in each of the outer conical friction ring carriers 60 , the second conical friction ring element being coupled to the shaft 18 for common rotation therewith.

[0122] The second conical friction ring element 64 is disposed between the outer conical friction ring carrier 60 and the first conical friction ring element 62 and can contact the inner conical surface 66 of the outer conical friction ring carrier 60 and the outer conical surface 68 of the first conical friction ring element 62 by applying an axial force to the cone clutch 58 .

[0123] Figure 4 A further friction clutch 22 is shown having friction clutch units 30 , 34 according to a third alternative.

[0124] and Figure 3 Compared to the friction clutch 22 shown in , the friction clutch unit 30 , 34 according to the third alternative has two second conical friction ring elements 64 which are coupled to the shaft 18 for common rotation therewith. Furthermore, no axial bearing is provided.

[0125] The first conical friction ring element 62 is arranged between two second conical friction ring elements 64, which have friction surfaces 70 facing the first conical friction ring elements 62. The corresponding inner conical surfaces 66 serve as bearing and friction surfaces on the outer side.

[0126] In addition, the spring units 32, 36 are also supported on the radially innermost conical friction ring element. Figure 3 In contrast to the friction clutch 22 shown in FIG. 6 , the radially innermost conical friction ring element is the second conical friction ring element 64 .

[0127] Since the actuating sleeve 26 and the second conical friction ring element 64 are coupled to the shaft 18 for common rotation therewith, the spring units 32 , 36 are not subject to any relative speeds which could cause friction and thus wear.

[0128] Therefore, this design does not require an axial bearing.

[0129] With regard to the displacement of the friction clutch 22 by means of the actuating sleeve 26 , the explanations regarding the first alternative also apply to the friction clutch units 30 , 34 according to the second and third alternatives.

[0130] Furthermore, it is also conceivable that one of the friction clutch units comprises a multi-disc clutch, the other friction clutch unit comprises a cone clutch, or that at least one of the friction clutch units comprises both a multi-disc clutch and a cone clutch (not shown in the figure).

[0131] As already indicated in the introduction, the actuating sleeve 26 can be moved via an actuator 28 .

[0132] Various types of actuators are contemplated for moving the actuation sleeve 26 .

[0133] By way of example only Figure 5 and Figure 6 , two possible actuators for a friction clutch 22 with a friction clutch unit 30 , 34 according to a third alternative are shown, but are also suitable for other embodiments.

[0134] To make it clearer, Figure 5 and Figure 6 In the drawings, only the most relevant components are provided with reference numerals.

[0135] like Figure 5 As shown in , the actuation sleeve 26 may be coupled to a ball ramp actuator 72 .

[0136] In this option, the actuating sleeve 26 is formed as part of a ball ramp actuator 72 which in turn has a drive 74 for moving the actuating sleeve 26 .

[0137] like Figure 6 As shown in , the actuation sleeve 26 may also be coupled to an electromagnetic actuator 76 .

[0138] The electromagnetic actuator 76 comprises a coil 78 , with the actuation sleeve 26 serving as a coil core and adapted to be moved axially along the shaft 18 by energizing the coil 78 .

[0139] Furthermore, it is also conceivable that the actuation sleeve 26 is coupled to an electromechanical actuator or a hydraulic actuator, although this is not shown in the figures.

Claims

1. A friction clutch of a multi-stage transmission (10), the friction clutch comprising: an actuating sleeve (26) seated on the shaft (18) and adapted to move linearly along the shaft (18) between a first engaged state and a second engaged state, a first friction clutch unit (30), which is arranged on one side of the actuating sleeve (26) in the axial direction and comprises a first clutch body (33), which is rotatably mounted on the shaft (18), a second friction clutch unit (34), which is arranged on the side of the actuating sleeve (26) opposite to the first friction clutch unit (30) in the axial direction and comprises a second clutch body (38), which is rotatably mounted on the shaft (18), a first spring unit (32), the first spring unit (32) being arranged axially between the actuating sleeve (26) and the first friction clutch unit (30), a second spring unit (36), the second spring unit (36) being arranged axially between the actuating sleeve (26) and the second friction clutch unit (34), The spring unit (32, 36) axially prestresses the two friction clutch units (30, 34) when the actuating sleeve (26) is in the neutral position. The actuating sleeve (26) produces a friction fit in the first friction clutch unit (30) in the first engaged state, and thus a rotational connection exists between the shaft (18) and the first clutch body (33), and The actuating sleeve (26) produces a friction fit in the second friction clutch unit (34) in the second engaged state, and thus a rotational connection exists between the shaft (18) and the second clutch body (38).

2. The friction clutch according to claim 1, characterized in that: At least on one side facing the friction clutch unit (30, 34), the actuating sleeve (26) has an axial bearing (50) assigned to the actuating sleeve (26), on which the respective spring unit (32, 36) is supported in the axial direction.

3. The friction clutch according to claim 2, characterized in that: The axial bearing (50) is a needle bearing (52) or a sliding bearing (54) including a sliding disk (56).

4. The friction clutch according to any one of the preceding claims, characterized in that In the neutral position of the actuating sleeve (26), at least approximately the same axial force acts on the first friction clutch unit (30) and the second friction clutch unit (34), respectively, which is caused by the associated first spring unit (32) or second spring unit (36) which is respectively prestressed between the actuating sleeve (26) and the first friction clutch unit (30) or the second friction clutch unit (34).

5. The friction clutch according to any one of the preceding claims, characterized in that When the actuating sleeve (26) is axially moved to the first engagement state, the magnitude of the axial force acting on the second friction clutch unit (34) is zero or reduced compared with the neutral position, and / or when the actuating sleeve (26) is axially moved to the second engagement state, the magnitude of the axial force acting on the first friction clutch unit (30) is zero or reduced compared with the neutral position.

6. A friction clutch according to any one of the preceding claims, characterised in that The first clutch body (33) and / or the second clutch body (38) are coupled to the gear (20) to rotate together with the gear (20).

7. A friction clutch according to any one of the preceding claims, characterised in that The first friction clutch unit (30) and / or the second friction clutch unit (34) comprises a multi-disk clutch (40).

8. The friction clutch according to claim 7, characterized in that: The corresponding multi-disc clutch (40) has an outer disk carrier (42), which is formed by the corresponding clutch body (33, 38) or is connected to the corresponding clutch body (33, 38) to rotate together with the corresponding clutch body (33, 38), and an outer disk (44) and an inner disk (46) are arranged in the outer disk carrier (42), the outer disk (44) is connected to the outer disk carrier (42) to rotate together with the outer disk carrier (42), and the inner disk (46) is connected to the shaft (18) to rotate together with the shaft (18).

9. The friction clutch according to claim 8, characterized in that: The outer disk (44) of the corresponding multi-disk clutch (40) is provided with friction linings (48) on both sides, and the inner disk (46) is a steel disk.

10. The friction clutch according to claim 9, characterized in that: The disc pack ends with an inner disc towards the actuating sleeve.

11. A friction clutch according to any one of the preceding claims, characterised in that The first friction clutch unit (30) and / or the second friction clutch unit (34) comprises a cone clutch (58).

12. The friction clutch according to claim 11, characterized in that: The respective cone clutch (58) has an outer cone friction ring carrier (60) coupled to the shaft (18) for common rotation therewith and formed by the respective clutch body (33, 38).

13. The friction clutch according to claim 12, characterized in that: At least a first conical friction ring element (62) and at least a second conical friction ring element (64) are at least partially arranged within the outer conical friction ring carrier (60), the first conical friction ring element (62) being coupled to the outer conical friction ring carrier (60) for common rotation therewith, and the second conical friction ring element (64) being coupled to the shaft (18) for common rotation therewith.

14. The friction clutch according to claim 13, characterized in that: The outer conical friction ring carrier (60) has an inner conical surface (66) against which the second conical friction ring element (64) can rest, the second conical friction ring element (64) being located between the outer conical friction ring carrier (60) and the first conical friction ring element (62).

15. The friction clutch according to claim 13 or 14, characterized in that: The respective cone clutch (58) comprises a first cone friction ring element (62) and two second cone friction ring elements (64), wherein the first cone friction ring element (62) is located between the two second cone friction ring elements (64), and the two second cone friction ring elements (64) each have a friction surface (70) facing the first cone friction ring element (62).

16. The friction clutch according to any one of claims 13 to 15, characterized in that: The respective elastic spring units (32, 36) are supported on the radially innermost conical friction ring elements (62, 64).

17. A friction clutch according to any one of the preceding claims, characterised in that The first elastic spring unit (32) and / or the second elastic spring unit (36) comprises at least one wave ring or a disc spring or a combination of these elements.

18. A friction clutch according to any one of the preceding claims, characterised in that The actuating sleeve (26) is arranged on the shaft (18) to rotate together with the shaft (18), or the actuating sleeve (26) is rotatably mounted on the shaft (18).

19. A friction clutch according to any one of the preceding claims, characterised in that The actuation sleeve (26) is coupled to an electromechanical actuator or a hydraulic actuator or an electromagnetic actuator (76) or a ball ramp actuator (72) for actuation.

20. An electric drive for a vehicle having a two-stage transmission and an electric motor (12) coupled via a friction clutch (22) according to one of the preceding claims.

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