Normally closed wet clutch and execution system thereof

Abstract

The normally-closed wet clutch comprises an outer hub, an inner hub and a friction plate set and further comprises a pressing piece set and an elastic pressing element, the pressing piece set comprises a movable pressing piece located at the first axial end of the friction plate set and a fixed pressing piece located at the second axial end of the friction plate set, and the elastic pressing element is arranged between the movable pressing piece and the fixed pressing piece. The pressing piece set can press the friction piece set under the action of the elastic pressing element, and the inner hub and the outer hub can rotate synchronously. The push rod sequentially penetrates through the fixed pressing piece and the friction plate set and abuts against the movable pressing piece, the push rod can move towards the first end under the action of hydraulic oil and push the movable pressing piece to loosen the friction plate set, the inner hub and the outer hub can relatively rotate, and the elastic pressing element stores energy. According to the normally-closed wet clutch, an executing mechanism does not need to continuously provide pressing force, the system power consumption is reduced, the friction plate set is normally closed, the dragging torque is reduced, and the system energy loss is reduced; the wet clutch is large in torque, sliding friction and power gear shifting are supported, and smoothness is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of clutches, in particular to a normally closed wet clutch and an execution system thereof. Background Art

[0002] Multi-speed hybrid transmissions and reducers are becoming more and more a hot topic in current research. A shifting system is required for multiple gears. Traditional synchronizer-type shifting mechanisms have poor smoothness due to power interruptions. Modern cars have increasingly higher requirements for driving experience. Traditional synchronizers are not suitable for multi-speed hybrid transmissions and electric reducers. The normally open clutch requires a pump to continuously provide clamping force, and the system power consumption is relatively high. Utility Model Content

[0003] The utility model aims to provide a normally closed wet clutch and an execution system thereof, which can improve the ride comfort of the vehicle, reduce system power consumption, and have a compact structure, and are suitable for multi-speed hybrid transmissions and electric reducers.

[0004] In order to solve the above technical problems, the utility model provides a normally closed wet clutch, comprising an outer hub, an inner hub arranged inside the outer hub, and a friction plate group, wherein the friction plate group is arranged between the inner hub and the outer hub.

[0005] It also includes a pressing plate group and an elastic pressing element, both of which are installed on the inner hub, the pressing plate group includes a movable pressing plate located at the first axial end of the friction plate group, and a fixed pressing plate located at the second axial end of the friction plate group, the elastic pressing element is located at the first axial end of the movable pressing plate, the pressing plate group can press the friction plate group under the elastic force of the elastic pressing element, and the inner hub and the outer hub can rotate synchronously;

[0006] It also includes a push rod, which passes through the fixed pressure plate and the friction plate group in sequence, and abuts against the side wall of the movable pressure plate facing the second end. The push rod can move toward the first end under the pressure of the hydraulic oil, and push the movable pressure plate to release the friction plate group. The elastic clamping element stores energy, and the inner hub and the outer hub can rotate relative to each other.

[0007] In the normally closed wet clutch of this embodiment, in the natural state, the movable pressure plate and the fixed pressure plate press the friction plate group under the elastic force of the elastic pressure element, so that the inner hub and the outer hub rotate synchronously to realize the engagement of the clutch; when it is necessary to control the clutch to separate, the actuator controls the pressure of the hydraulic oil to increase, the push rod moves toward the first end under the pressure of the hydraulic oil, and pushes the movable pressure plate to loosen the friction plate group, the elastic pressure element is in an energy storage state, the inner hub and the outer hub can rotate relative to each other, and the clutch is separated; when the pressure of the hydraulic oil is removed, the movable pressure plate moves toward the second end under the restoring force of the elastic pressure element, the fixed pressure plate and the movable pressure plate re-press the friction plate group, and the clutch is re-engaged, the push rod moves toward the second end under the restoring force of the elastic pressure element, and returns to the initial position. The initial position mentioned here, that is, the position of the push rod when the clutch is in the engaged state, is also the limit position of the push rod moving toward the second end.

[0008] It can be seen that the normally closed wet clutch of this embodiment, in the natural state, the elastic pressing element applies the pressing force to achieve the engagement of the clutch, and there is no need for the actuator to continuously provide the pressing force, thereby reducing the system power consumption, and the friction plate group is normally closed, which can reduce the drag torque of the clutch and reduce the energy loss of the system; at the same time, the wet clutch has a large torque, can support sliding friction, support power shifting, improve smoothness, and is suitable for multi-speed hybrid transmissions and electric reducers.

[0009] In addition, in this embodiment, the push rod passes through the middle of the fixed pressure plate and the friction plate group and abuts against the movable pressure plate. The push rod does not need to occupy radial space alone, making the overall structure of the normally closed wet clutch of this embodiment more compact.

[0010] Optionally, it also includes a base and a clutch piston, the inner hub is rotatably connected to the base, a hydraulic oil channel is provided inside the base, the clutch piston portion is axially slidably installed inside the hydraulic oil channel and is circumferentially sealed, the clutch piston and the push rod are axially limitedly connected and can rotate relative to each other in the circumferential direction, and the clutch piston can move toward the first end under the pressure of the hydraulic oil.

[0011] Optionally, the push rod includes a circular ring portion and a plurality of rod portions, the circular ring portion is used to connect to the clutch piston, the rod portions are connected to an axial first end of the circular ring portion, and the rod portions are distributed at intervals along the circumference of the circular ring portion.

[0012] Optionally, the fixed pressing plate is provided with first through holes spaced apart along the circumferential direction, and the rod portion passes through the corresponding first through holes.

[0013] Optionally, the friction plate group includes friction plates and steel plates, the friction plates and the steel plates are staggered in the axial direction, the steel plates at both ends are located at the axial outermost ends of the friction plate group, the first one of the friction plates and the steel plates is connected to the inner hub, the friction plates and the first one of the steel plates are provided with second through holes spaced apart in the circumferential direction, and the rod portion passes through the corresponding second through hole;

[0014] The friction plate and the second one of the steel plates are connected to the outer hub, and the friction plate and the second one of the steel plates are located at the radial outer end of the rod portion.

[0015] Optionally, the base has an inner mounting hole and further comprises a support sleeve, wherein the support sleeve is partially connected to the interior of the inner mounting hole, and the inner hub is rotatably connected to the support sleeve.

[0016] Optionally, the support sleeve and the inner mounting hole are threadedly connected, and the inner hole of the support sleeve is provided with a driving spline.

[0017] The present embodiment also provides an actuation system of a normally closed wet clutch, comprising the aforementioned normally closed wet clutch, and also comprising an actuation mechanism, wherein the actuation mechanism comprises a motor, a transmission unit and an actuation master cylinder, wherein the transmission unit comprises a first transmission part and a second transmission part which are transmission-connected, wherein the first transmission part is connected to the output shaft of the motor, and the second transmission part is connected to the master cylinder push rod of the actuation master cylinder, wherein the transmission unit can convert the rotation of the output shaft of the motor into the axial movement of the master cylinder push rod, and the hydraulic oil passage of the actuation master cylinder and the normally closed wet clutch is connected.

[0018] The execution system of the normally closed wet clutch of this embodiment includes the normally closed wet clutch mentioned above, and thus has the same technical effects as the normally closed wet clutch mentioned above, which will not be described in detail here.

[0019] At the same time, compared with the traditional hydraulic control structure, the hydrostatic actuator of this embodiment has higher control accuracy, simple structure, lighter weight, no system leakage, and low energy consumption. In practice, the actuator can be arranged inside the housing of the gearbox, and the arrangement is flexible.

[0020] Optionally, a pressure sensor is further included, and the pressure sensor is arranged inside the actuator master cylinder.

[0021] Optionally, a displacement sensor is further included, wherein the displacement sensor is configured to detect the axial displacement of the master cylinder push rod. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 An axial cross-sectional view of a specific embodiment of a normally closed wet clutch provided in the present application;

[0023] Figure 2 for Figure 1 Schematic diagram of the structure of the push rod in the normally closed wet clutch;

[0024] Figure 3 for Figure 1 Schematic diagram of the local structure of a normally closed wet clutch;

[0025] Figure 4 A schematic structural diagram of a specific embodiment of the execution system of the normally closed wet clutch provided in this application;

[0026] in, Figure 1-Figure 4 The reference numerals in the figures are described as follows:

[0027] 10-normally closed wet clutch; 100-outer hub; 101-inner hub; 102-friction plate group; 1021-friction plate; 1022-steel plate; 103-elastic clamping element; 104-movable pressure plate; 105-fixed pressure plate; 106-base; 106a-hydraulic oil channel; 106b-pressure oil inlet; 107-clutch piston; 108-push rod; 1081-circular ring; 1082-rod; 109-release bearing; 110-support seat sleeve; 110a-driving spline; 111-connecting bearing; 112-circlip; a-first through hole;

[0028] 20-actuator; 200-motor; 201-transmission unit; 2011-first transmission part; 2012-second transmission part; 202-executor master cylinder; 2021-master cylinder push rod; 203-displacement sensor; 204-controller. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0030] The “plurality” mentioned herein generally means more than two; and when “plurality” is used to indicate the number of certain components, it does not indicate the relationship between the quantities of these components.

[0031] Please refer to Figure 1 , Figure 1 An axial cross-sectional view of a specific embodiment of the normally closed wet clutch provided in the present application.

[0032] This embodiment provides a normally closed wet clutch 10, including an outer hub 100, an inner hub 101 disposed inside the outer hub 100, and a friction plate group 102, wherein the friction plate group 102 is disposed between the inner hub 101 and the outer hub 100.

[0033] It also includes a pressing plate group and an elastic pressing element 103, both of which are installed on the inner hub 101, the pressing plate group includes a movable pressing plate 104 located at the first axial end of the friction plate group 102, and a fixed pressing plate 105 located at the second axial end of the friction plate group 102, the elastic pressing element 103 is located at the first axial end of the movable pressing plate 104, the pressing plate group can press the friction plate group 102 under the elastic force of the elastic pressing element 103, and the inner hub 101 and the outer hub 100 can rotate synchronously;

[0034] It also includes a push rod 108, which passes through the fixed pressure plate 105 and the friction plate group 102 in sequence, and abuts against the side wall of the movable pressure plate 104 facing the second end. The push rod 108 can move toward the first end under the pressure of the hydraulic oil, and push the movable pressure plate 104 to relax the friction plate group 102. The elastic clamping element 103 stores energy, and the inner hub 101 and the outer hub 100 can rotate relative to each other.

[0035] It should be noted that the fixed pressure plate 105 is relatively fixed to the inner hub 101 along the axial direction, and the movable pressure plate 104 is able to move along the axial direction of the inner hub 101 under the action of the push rod 108 or the elastic pressing element 103. In this way, the position of the fixed pressure plate 105 remains unchanged, and when the movable pressure plate 104 moves in the direction close to the fixed pressure plate 105, the fixed pressure plate 105 and the movable pressure plate 104 can gradually press the friction plate group 102 to achieve the engagement of the clutch; when the movable pressure plate 104 moves in the direction away from the fixed pressure plate 105, the fixed pressure plate 105 and the movable pressure plate 104 can gradually loosen the friction plate group 102 to achieve the disengagement of the clutch.

[0036] In the normally closed wet clutch 10 of this embodiment, in the natural state, the movable pressure plate 104 and the fixed pressure plate 105 press the friction plate group 102 under the elastic force of the elastic pressing element 103, so that the inner hub 101 and the outer hub 100 rotate synchronously to achieve the engagement of the clutch; when it is necessary to control the clutch to be separated, the actuator controls the pressure of the hydraulic oil to increase, the push rod 108 moves toward the first end under the pressure of the hydraulic oil, and pushes the movable pressure plate 104 to relax the friction plate group 102, the elastic pressing element 103 is in an energy storage state, the inner hub 101 and the outer hub 100 can rotate relatively to achieve the separation of the clutch; when the pressure of the hydraulic oil is removed, the movable pressure plate 104 moves toward the second end under the restoring force of the elastic pressing element 103, the fixed pressure plate 105 and the movable pressure plate 104 re-press the friction plate group 102, and the clutch is re-engaged, and the push rod 108 moves toward the second end under the restoring force of the elastic pressing element 103 and returns to the initial position.

[0037] The initial position mentioned here, i.e., the position of the push rod 108 when the clutch is in the engaged state, is also the limit position of the push rod 108 moving toward the second end.

[0038] It can be seen that the normally closed wet clutch 10 of this embodiment, in the natural state, is engaged by the elastic pressing element 103 applying the pressing force, and there is no need for the actuator to continuously provide the pressing force, thereby reducing the system power consumption, and the friction plate group 102 is normally closed, which can reduce the drag torque of the clutch and reduce the energy loss of the system; at the same time, the wet clutch has a large torque, can support sliding friction, support power shifting, improve smoothness, and is suitable for multi-speed hybrid transmissions and electric reducers.

[0039] In addition, in this embodiment, the push rod 108 passes through the middle of the fixed pressure plate 105 and the friction plate group 102, and abuts against the movable pressure plate 104. The push rod 108 does not need to occupy radial space alone, making the overall structure of the normally closed wet clutch 10 of this embodiment more compact.

[0040] In practice, there is no limitation on the structure of the elastic pressing element 103 . For example, the elastic pressing element 103 may be a butterfly spring, a diaphragm spring, or the like.

[0041] As mentioned above, the fixed pressing plate 105 and the inner hub 101 are relatively fixed along the axial direction. Specifically in this embodiment, Figure 1 As shown, the peripheral wall of the inner hub 101 is provided with an abutment wall facing the second end, the fixed pressing plate 105 is sleeved on the outer periphery of the inner hub 101, and the side wall of the fixed pressing plate 105 facing the first end abuts against the abutment wall, and also includes a retaining spring 112, which is fixedly sleeved on the outer periphery of the inner hub 101, and the side wall of the fixed pressing plate 105 facing the second end abuts against the retaining spring 112, thereby realizing axial fixation of the fixed pressing plate 105 and the inner hub 101.

[0042] like Figure 1 As shown, both the inner hub 101 and the outer hub 100 have connecting splines. In practice, one of the inner hub 101 and the outer hub 100 can be connected to a power mechanism, such as an engine or a motor; and the other can be connected to an output mechanism.

[0043] Furthermore, the normally closed wet clutch 10 of this embodiment also includes a base 106 and a clutch piston 107. The inner hub 101 is rotatably connected to the base 106. A hydraulic oil channel 106a is provided inside the base 106. The clutch piston 107 is partially slidably installed in the hydraulic oil channel 106a along the axial direction and is sealed along the circumferential direction. The clutch piston 107 and the push rod 108 are axially limitedly connected and can rotate relative to each other along the circumferential direction. The clutch piston 107 can move toward the first end under the pressure of the hydraulic oil.

[0044] In this way, the clutch piston 107 is directly affected by the pressure of the hydraulic oil. When the pressure of the hydraulic oil inside the hydraulic oil channel 106a increases, the clutch piston 107 can move toward the first end under the action of the pressure of the hydraulic oil, and drive the push rod 108 to move toward the first end synchronously; when the pressure of the hydraulic oil is removed, the clutch piston 107 moves synchronously toward the second end driven by the push rod 108 and returns to the initial position.

[0045] The initial position mentioned here, that is, the position of the clutch piston 107 when the clutch is in the engaged state, is also the limit position of the clutch piston 107 moving toward the second end.

[0046] It can be understood that since the push rod 108 passes through the fixed pressure plate 105 and the middle of the friction plate group 102, the push rod 108 can rotate synchronously with the inner hub 101. Therefore, the clutch piston 107 and the push rod 108 are axially limited and connected, and can rotate relative to each other in the circumferential direction, which can ensure that the clutch piston 107 and the push rod 108 move synchronously in the axial direction without affecting the rotation of the push rod 108, thereby ensuring the smoothness of the rotation of the push rod 108.

[0047] In practice, the base 106 is further provided with a pressure oil inlet 106 b , which is communicated with the hydraulic oil passage 106 a , and the pressure oil inlet 106 b is used to communicate with the actuator main cylinder in the actuator mechanism.

[0048] In addition, if Figure 1 As shown, in this embodiment, the pressure oil inlet 106b is arranged on the end wall of the second end of the base 106. When the actuator and the normally closed wet clutch 10 are connected, the actuator is located at the second end of the normally closed wet clutch 10, that is, the two are arranged axially, which can reduce the radial space occupancy of the entire system.

[0049] Further, as mentioned above, the clutch piston 107 and the push rod 108 are axially limited and connected, and can rotate along the circumferential direction. In this embodiment, Figure 1 As shown, the normally closed wet clutch 10 further includes a release bearing 109 , which is connected between the clutch piston 107 and the push rod 108 .

[0050] The arrangement of the release bearing 109 as above can ensure the reliable axial connection between the clutch piston 107 and the push rod 108, so that the clutch piston 107 and the push rod 108 can move synchronously along the axial direction without affecting the rotation of the push rod 108, thereby ensuring the smooth rotation of the push rod 108.

[0051] Please refer to Figure 1-Figure 2 , Figure 2 for Figure 1 Schematic diagram of the structure of the push rod in a normally closed wet clutch.

[0052] In this embodiment, the push rod 108 includes an annular portion 1081 and a plurality of rod portions 1082 . The annular portion 1081 is used to connect to the clutch piston 107 . The rod portions 1082 are connected to the axial first end of the annular portion 1081 . The rod portions 1082 are distributed at intervals along the circumference of the annular portion 1081 .

[0053] As configured above, the annular portion 1081 serves to connect the clutch piston 107, ensuring reliable connection between the push rod 108 and the clutch piston 107. The plurality of rod portions 1082 are distributed at intervals along the circumference of the annular portion 1081. The force from the hydraulic oil acts on the movable pressure plate 104 through the plurality of rod portions 1082, ensuring that the movable pressure plate 104 is subjected to balanced force along the circumferential direction, so that the movable pressure plate 104 can only move axially under the thrust of the rod portion 1082, thereby reducing the possibility of the movable pressure plate 104 producing other movements except axial movement.

[0054] Depend on Figure 1 It can be seen that in this embodiment, the clutch piston 107 is partially inserted into the annular portion 1081 , the inner ring of the release bearing 109 is connected to the clutch piston 107 , and the outer ring of the release bearing 109 is connected to the annular portion 1081 .

[0055] Among them, the inner ring of the release bearing 109 and the clutch piston 107 can be connected by interference fit, welding and other methods; the outer ring of the release bearing 109 and the annular portion 1081 can be connected by interference fit, welding and other methods.

[0056] In practice, the annular portion 1081 and the rod portion 1082 may be integrally formed, or may be separate structures that are then fixed together.

[0057] Please refer to Figure 3 , Figure 3 for Figure 1 Schematic diagram of the partial structure of a normally closed wet clutch.

[0058] In this embodiment, the fixed pressing plate 105 is provided with first through holes a spaced apart along the circumferential direction, and the rod portion 1082 passes through the corresponding first through hole a, that is, the first through hole a serves to avoid the rod portion 1082 .

[0059] Please continue to refer to Figure 1 In this embodiment, the friction plate group 102 includes a friction plate 1021 and a steel plate 1022. The friction plate 1021 and the steel plate 1022 are alternately arranged along the axial direction. The steel plates 1022 at both ends are located at the axial outermost ends of the friction plate group 102. The steel plate 1022 is connected to the inner hub 101. The steel plate 1022 is provided with second through holes distributed at intervals along the circumferential direction. The rod portion 1082 passes through the corresponding second through hole. The friction plate 1021 is connected to the outer hub 100. The friction plate 1021 is located at the radial outer end of the push rod 108.

[0060] As set above, the steel sheet 1022 is provided with second through holes distributed at intervals along the circumferential direction, which play the role of avoiding the rod portion 1082. The rod portion 1082 is partially inserted into the steel sheet 1022, and the rod portion 1082 and the steel sheet 1022 are limited circumferentially. The rod portion 1082 and the steel sheet 1022 can rotate synchronously with the inner hub 101, and the friction plate 1021 is located at the radial outer end of the push rod 108, that is, the friction plate 1021 has no connection relationship with the push rod 108, and the rod portion 1082 will not interfere with the rotation of the outer hub 100, so that when the clutch is in a disengaged state, the inner hub 101 and the outer hub 100 can rotate relatively.

[0061] At the same time, the steel sheets 1022 at both ends are located at the axial outermost ends of the friction plate group 102, that is, the fixed pressure plate 105 and the movable pressure plate 104 are in contact with the steel sheet 1022. Compared with the friction plate 1021, the steel sheet 1022 is not easy to wear, which can increase the service life of the friction plate group 102.

[0062] In practice, the friction plate 1021 and the steel plate 1022 can also have a second connection method, specifically: the friction plate 1021 and the steel plate 1022 are arranged alternately along the axial direction, and the steel plates 1022 at both ends are located at the axial outermost ends of the friction plate group 102, the friction plate 1021 is connected to the inner hub 101, and the friction plate 1021 is provided with second through holes distributed along the circumferential direction, and the rod portion 1082 passes through the corresponding second through hole, and the steel plate 1022 is connected to the outer hub 100, and the steel plate 1022 is located at the radial outer end of the push rod 108, which can also achieve the above-mentioned technical effects.

[0063] To sum up, in practice, the first one of the friction plate 1021 and the steel plate 1022 is connected to the inner hub 101, the first one of the friction plate 1021 and the steel plate 1022 is provided with second through holes distributed along the circumferential direction, the rod portion 1082 passes through the corresponding second through hole, the second one of the friction plate 1021 and the steel plate 1022 is connected to the outer hub 100, and the second one of the friction plate 1021 and the steel plate 1022 is located at the radial outer end of the push rod 108.

[0064] Please continue to refer to Figure 1 In this embodiment, the base 106 has an inner mounting hole and also includes a support seat sleeve 110 . The support seat sleeve 110 is partially connected to the inner mounting hole, and the inner hub 101 is rotatably connected to the support seat sleeve 110 .

[0065] In this way, the support sleeve 110 can play the role of installing the inner hub 101, thereby achieving a reliable connection between the base 106 and the inner hub 101.

[0066] The inner hub 101 is rotatably connected to the support sleeve 110. Specifically, Figure 1As shown, the inner hub 101 has a connecting portion, which is partially mounted on the outer periphery of the supporting sleeve 110, and also includes a connecting bearing 111, which is arranged between the connecting portion and the supporting sleeve 110, the inner ring of the connecting bearing 111 is connected to the supporting sleeve 110, and the outer ring of the connecting bearing 111 is connected to the connecting portion.

[0067] The arrangement of the connecting bearing 111 as above ensures that the connection between the inner hub 101 and the supporting seat sleeve 110 is stable and will not affect the rotation of the inner hub 101, thereby ensuring the smooth rotation of the inner hub 101.

[0068] In practice, the inner ring of the connecting bearing 111 and the supporting sleeve 110 may be connected by interference fit or welding fixation, etc.; the outer ring of the connecting bearing 111 and the connecting portion may be connected by interference fit or welding fixation, etc.

[0069] In this embodiment, the support seat sleeve 110 is threadedly connected to the inner mounting hole. Figure 1 As shown, the inner hole of the support seat sleeve 110 is provided with a driving spline 110a. During the installation process of the support seat sleeve 110, the driving spline 110a can cooperate with the spline of the tightening mechanism to achieve a torsion-resistant connection between the support seat sleeve 110 and the tightening mechanism, making it easier for the tightening mechanism to tighten the support seat sleeve 110.

[0070] Combination Figure 1 It is understood that during the installation of the inner hub 101, the tightening mechanism is usually located at the second end of the base 106, and the output shaft of the tightening mechanism extends from the second end to the first end, and passes through the inner mounting hole of the base 106 to enter the inner hole of the support seat sleeve 110. Therefore, in this embodiment, the drive spline 110a is arranged at the second end of the inner hole of the support seat sleeve 110 to facilitate connection with the tightening mechanism.

[0071] Of course, in practice, the support sleeve 110 and the base 106 are not limited to the above-mentioned threaded connection method. For example, the support sleeve 110 and the inner mounting hole may be welded and fixed, or fixed by a threaded connector. In this case, there is no need to set the above-mentioned drive spline 110a.

[0072] In practice, when the normally closed wet clutch 10 of this embodiment is arranged inside a gearbox, the base 106 can be connected to the housing of the gearbox by threaded connectors such as bolts.

[0073] Please refer to Figure 4 , Figure 4 This is a simplified structural diagram of a specific embodiment of the execution system of the normally closed wet clutch provided in this application.

[0074] The present embodiment also provides an actuation system of a normally closed wet clutch, comprising the aforementioned normally closed wet clutch 10, and also comprising an actuating mechanism 20, wherein the actuating mechanism 20 comprises a motor 200, a transmission unit 201 and an actuating master cylinder 202, wherein the transmission unit 201 comprises a first transmission part 2011 and a second transmission part 2012 which are transmission-connected, wherein the first transmission part 2011 is connected to the output shaft of the motor 200, and the second transmission part 2012 is connected to the master cylinder push rod 2021 of the actuating master cylinder 202, wherein the transmission unit 201 can convert the rotation of the output shaft of the motor 200 into the axial movement of the master cylinder push rod 2021, and the actuating master cylinder 202 is connected to the hydraulic oil passage 106a of the normally closed wet clutch 10.

[0075] The execution system of the normally closed wet clutch of this embodiment includes the normally closed wet clutch 10 mentioned above, and thus has the same technical effects as the normally closed wet clutch 10 mentioned above, which will not be described in detail herein.

[0076] Meanwhile, in the actuation system of the normally closed wet clutch of this embodiment, the actuation mechanism 20 is a hydrostatic actuation mechanism. Figure 4 It can be seen that, in practice, the actuator 20 also includes a controller 204, and the controller 204 is electrically connected to the motor 200. When the clutch needs to be disengaged, the controller 204 controls the output shaft of the motor 200 to rotate, and the transmission unit 201 converts the rotation of the output shaft of the motor 200 into an axial movement of the master cylinder push rod 2021, so that the pressure of the hydraulic oil in the main cylinder 202 and the hydraulic oil channel 106a increases, and the clutch piston 107 and the push rod 108 move toward the first end under the pressure of the hydraulic oil, so that the clutch is disengaged; when the clutch needs to be engaged, the controller 204 controls the output shaft of the motor 200 to rotate in the opposite direction, and the transmission unit 201 converts the rotation of the output shaft of the motor 200 into an axial movement of the master cylinder push rod 2021, so that the pressure of the hydraulic oil in the main cylinder 202 and the hydraulic oil channel 106a decreases, and the clutch piston 107 and the push rod 108 move toward the second end under the restoring force of the elastic clamping element 103, so that the clutch is engaged.

[0077] Compared with the traditional hydraulic control structure, the hydrostatic actuator of this embodiment has higher control accuracy, simple structure, lighter weight, no system leakage, and low energy consumption. In practice, the actuator 20 can be arranged inside the housing of the gearbox, and the arrangement is flexible.

[0078] In addition, the hydrostatic actuator of this embodiment can achieve high pressure (60 MPa) of the hydraulic system, which can reduce the number of friction plates 1021 of the clutch compared to ordinary hydraulic systems (15 MPa).

[0079] In this embodiment, the transmission unit 201 includes a ball screw transmission unit, which includes a screw and a nut connected by threads, wherein the screw forms a first transmission part 2011 for connecting to the output shaft of the motor 200, and the nut forms a second transmission part 2012 for connecting to the master cylinder push rod 2021 that executes the master cylinder 202. The output shaft of the motor 200 drives the screw to rotate, and under the action of the threaded cooperation of the screw and the nut, the nut moves along the axial direction of the screw, thereby realizing the axial displacement of the master cylinder push rod 2021.

[0080] In practice, the structure of the transmission unit 201 is not limited. For example, the transmission unit 201 may also be a worm gear transmission unit, a roller screw transmission unit, a trapezoidal screw transmission unit, a rack and pinion transmission unit, etc.

[0081] In this embodiment, the actuation system of the normally closed wet clutch further includes a pressure sensor, and the pressure sensor is disposed inside the actuation master cylinder 202 .

[0082] In this way, the size of the pressing force provided by the actuator 20 can be directly obtained through the pressure sensor, so as to realize system torque control and improve the accuracy of control.

[0083] Furthermore, if Figure 4 As shown, the execution system of the normally closed wet clutch in this embodiment further includes a displacement sensor 203 , and the displacement sensor 203 is configured to detect the axial displacement of the master cylinder push rod 2021 .

[0084] In this way, in the small torque section of the clutch (0-30N.m), since the pressure fluctuation will have a certain impact on the system control, displacement control can be used to improve the accuracy of control. The pressure signal in this working condition is used as a system redundancy check; in the large torque section of the clutch, the pressure fluctuation accounts for a small proportion of the pressure, and pressure control can be used to achieve system torque control. The displacement signal in this working condition is used as a system redundancy check.

[0085] The above is a detailed introduction to a normally closed wet clutch and its execution system provided by the utility model. This article uses specific examples to illustrate the principle and implementation method of the utility model. The description of the above embodiments is only used to help understand the method and core idea of ​​the utility model. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the utility model, the utility model can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the utility model.

Claims

1. A normally closed wet clutch, characterized in that: The invention comprises an outer hub (100), an inner hub (101) arranged inside the outer hub (100), and a friction plate group (102), wherein the friction plate group (102) is arranged between the inner hub (101) and the outer hub (100). It also includes a pressing plate group and an elastic pressing element (103), wherein the pressing plate group and the elastic pressing element (103) are both mounted on the inner hub (101), the pressing plate group includes a movable pressing plate (104) located at the first axial end of the friction plate group (102), and a fixed pressing plate (105) located at the second axial end of the friction plate group (102), the elastic pressing element (103) is located at the first axial end of the movable pressing plate (104), the pressing plate group can press the friction plate group (102) under the elastic force of the elastic pressing element (103), and the inner hub (101) and the outer hub (100) can rotate synchronously; It also includes a push rod (108), which passes through the fixed pressure plate (105) and the friction plate group (102) in sequence and abuts against the side wall of the movable pressure plate (104) facing the second end. The push rod (108) can move toward the first end under the pressure of hydraulic oil and push the movable pressure plate (104) to release the friction plate group (102). The elastic clamping element (103) stores energy, and the inner hub (101) and the outer hub (100) can rotate relative to each other.

2. The normally closed wet clutch according to claim 1, characterized in that: It also includes a base (106) and a clutch piston (107), wherein the inner hub (101) is rotatably connected to the base (106), a hydraulic oil passage (106a) is provided inside the base (106), the clutch piston (107) is partially slidably mounted inside the hydraulic oil passage (106a) along the axial direction and is sealed along the circumferential direction, the clutch piston (107) and the push rod (108) are axially limitedly connected and can rotate relative to each other along the circumferential direction, and the clutch piston (107) can move toward the first end under the pressure of the hydraulic oil.

3. The normally closed wet clutch according to claim 2, characterized in that: The push rod (108) comprises a circular ring portion (1081) and a plurality of rod portions (1082), wherein the circular ring portion (1081) is used to connect to the clutch piston (107), and the rod portions (1082) are connected to the axial first end of the circular ring portion (1081), and the rod portions (1082) are distributed at intervals along the circumference of the circular ring portion (1081).

4. The normally closed wet clutch according to claim 3, characterized in that: The fixed pressing plate (105) is provided with first through holes (a) distributed at intervals along the circumferential direction, and the rod portion (1082) passes through the inside of the corresponding first through hole (a).

5. The normally closed wet clutch according to claim 3, characterized in that: The friction plate group (102) comprises a friction plate (1021) and a steel plate (1022), the friction plate (1021) and the steel plate (1022) are arranged alternately in the axial direction, the steel plates (1022) at both ends are located at the axial outermost ends of the friction plate group (102), the first one of the friction plate (1021) and the steel plate (1022) is connected to the inner hub (101), the friction plate (1021) and the first one of the steel plate (1022) are provided with second through holes distributed at intervals in the circumferential direction, and the rod portion (1082) passes through the corresponding second through hole; The second one of the friction plate (1021) and the steel plate (1022) is connected to the outer hub (100), and the second one of the friction plate (1021) and the steel plate (1022) is located at the radial outer end of the rod portion (1082).

6. The normally closed wet clutch according to any one of claims 2 to 5, characterized in that: The base (106) has an inner mounting hole, and further comprises a support seat sleeve (110), wherein a portion of the support seat sleeve (110) is connected to the interior of the inner mounting hole, and the inner hub (101) is rotatably connected to the support seat sleeve (110).

7. The normally closed wet clutch according to claim 6, characterized in that: The support seat sleeve (110) is threadedly connected to the inner mounting hole, and the inner hole of the support seat sleeve (110) is provided with a driving spline (110a).

8. An actuation system for a normally closed wet clutch, characterized in that: The normally closed wet clutch (10) comprises a motor (200), a transmission unit (201) and an actuating master cylinder (202), wherein the transmission unit (201) comprises a first transmission part (2011) and a second transmission part (2012) in transmission connection, wherein the first transmission part (2011) is connected to the output shaft of the motor (200), and the second transmission part (2012) is connected to the master cylinder push rod (2021) of the actuating master cylinder (202), wherein the transmission unit (201) is capable of converting the rotation of the output shaft of the motor (200) into the axial movement of the master cylinder push rod (2021), and the actuating master cylinder (202) is connected to the hydraulic oil passage (106a) of the normally closed wet clutch (10).

9. The actuation system of the normally closed wet clutch according to claim 8, characterized in that: It also includes a pressure sensor, which is arranged inside the main actuator cylinder (202).

10. The actuation system of the normally closed wet clutch according to claim 9, characterized in that: It also includes a displacement sensor (203), wherein the displacement sensor (203) is configured to detect the axial displacement of the master cylinder push rod (2021).

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