Electric bridge drive system and vehicle

Abstract

The application provides an electric axle driving system and a vehicle. The transmission of the electric axle driving system comprises a planetary gear mechanism and a clutch mechanism, the torque of a motor is input from a sun gear of the planetary gear mechanism and output from a planet carrier, and a sliding engagement assembly of the clutch mechanism is arranged on a housing of the transmission in a sliding manner relative to the housing in the axial direction. The sliding engagement assembly can make the ring gear unable to rotate relative to the housing of the transmission, make the planet carrier unable to rotate relative to the housing of the transmission, or make the ring gear and the planet carrier able to rotate freely relative to the housing of the transmission. Therefore, the electric axle driving system can selectively be in three different states by sliding the sliding engagement assembly of the clutch mechanism along the axial direction, so that the functions of connecting or disconnecting the transmission connection between the wheels and the motor of the vehicle can be realized as desired without greatly affecting the overall layout.

Description

Technical Field

[0001] The present invention relates to the field of vehicles, and more particularly to an electric bridge drive system for a vehicle and a vehicle comprising the electric bridge drive system. Background Art

[0002] Currently, e-bridge drive systems integrate the motor control unit, motor, and transmission into a three-in-one layout. They can be used in both pure electric and hybrid vehicles to propel the vehicle. As a result, e-bridge drive systems offer compact design and flexible application.

[0003] An electric axle drive system includes a motor, a transmission, a differential, and two half-shafts. The sun gear of the transmission's planetary gear mechanism is drivingly coupled to the transmission's input shaft to receive torque from the motor via the input shaft. The ring gear of the planetary gear mechanism is permanently fixed relative to the transmission housing, preventing rotation relative to the housing. The planetary gear carrier of the planetary gear mechanism is drivingly coupled to the differential to transmit torque to the differential, thereby enabling transmission of torque to the two half-shafts and ultimately the vehicle's wheels.

[0004] In an e-axle drive system with the aforementioned structure, the motor is always connected to the vehicle's wheels via the transmission and differential, and the transmission connection between the motor and the wheels cannot be disconnected as needed. Adding traditional synchronizers, clutches, and other systems would significantly alter the overall e-axle drive system layout, increase the axial length of the transmission, and increase costs. Summary of the Invention

[0005] The present invention was developed in light of the aforementioned shortcomings of the prior art. One object of the present invention is to provide a novel electric bridge drive system that, while taking into account both the structure and cost of the electric bridge drive system, can disconnect the transmission connection between the motor and the vehicle's wheels as needed. Another object of the present invention is to provide a vehicle incorporating the aforementioned electric bridge drive system.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions.

[0007] The present invention provides the following electric bridge drive system, the electric bridge drive system comprising:

[0008] motors; and

[0009] A transmission comprising an input shaft, a planetary gear mechanism, a clutch mechanism, and a housing; the input shaft is drivingly coupled to the motor; the planetary gear mechanism comprises a sun gear, a plurality of planetary gears, a planetary gear carrier, and a ring gear; the sun gear is drivingly coupled to the input shaft; the planetary gear carrier is used to transmit torque to the outside of the planetary gear mechanism;

[0010] The clutch mechanism includes a sliding engagement assembly, which is arranged on the housing in a manner such that it cannot rotate relative to the transmission housing but can slide relative to the housing in the axial direction of the electric bridge drive system. The sliding engagement assembly can be in the following three positions in the axial direction:

[0011] a first position in which the ring gear is engaged with the sliding engagement assembly such that the ring gear cannot rotate relative to the housing;

[0012] a second position in which the planet wheel carrier engages the sliding joint assembly such that the planet wheel carrier cannot rotate relative to the housing; and

[0013] and a third position in which the ring gear and the planet carrier are both disengaged from the sliding joint assembly, such that the ring gear and the planet carrier are both rotatable relative to the housing.

[0014] Preferably, the sliding engagement assembly comprises a sliding member and an actuator assembled together, the sliding member is used to selectively engage with the ring gear or the planetary wheel carrier, and the actuator can drive the sliding member to slide in the axial direction.

[0015] More preferably, the sliding member is formed with a plurality of internal teeth,

[0016] The clutch mechanism also includes a first coupling member and a second coupling member, the first coupling member being arranged on the ring gear in a manner that cannot rotate relative to the ring gear, the first coupling member being formed with a plurality of first external teeth for engaging with the plurality of internal teeth, and the second coupling member being arranged on the planetary gear carrier in a manner that cannot rotate relative to the planetary gear carrier, the second coupling member being formed with a plurality of second external teeth for engaging with the plurality of internal teeth.

[0017] More preferably, the plurality of first external teeth and the plurality of second external teeth are spaced apart in the axial direction so that in the first position the plurality of internal teeth are engaged with the plurality of first external teeth, in the second position the plurality of internal teeth are engaged with the plurality of second external teeth, and in the third position the plurality of internal teeth are located axially between the plurality of first external teeth and the plurality of second external teeth.

[0018] More preferably, the ring gear is located between the step portion of the housing and a limiting assembly installed on the housing, so that the ring gear is fixed relative to the housing in the axial direction.

[0019] More preferably, the sliding joint assembly is driven by another motor to move in the axial direction.

[0020] More preferably, the planetary gear mechanism is a double planetary gear mechanism, the planetary gears include a first planetary gear and a second planetary gear fixed to each other in a coaxial manner, the first planetary gear is always in meshing state with the sun gear, the second planetary gear is always in meshing state with the ring gear, and the first planetary gear and the second planetary gear are both mounted on the planetary gear carrier.

[0021] More preferably, the rotor of the motor is mounted on the input shaft in a coaxial manner with the input shaft.

[0022] More preferably, the electric bridge drive system also includes a differential and two half-shafts extending from the differential toward both sides of the axial direction, the planetary wheel carrier is connected to the differential, the two half-shafts are arranged coaxially with the input shaft, and the input shaft is a hollow shaft, so that one of the two half-shafts passes through the input shaft and can rotate independently of the input shaft.

[0023] The present invention also provides a vehicle as follows, comprising the electric bridge drive system described in any one of the above technical solutions.

[0024] By adopting the above technical solution, the present invention provides a novel electric bridge drive system and a vehicle including the same. The transmission of the electric bridge drive system includes a planetary gear mechanism and a clutch mechanism. The torque of the motor is input from the sun gear of the planetary gear mechanism via the input shaft of the transmission and then output from the planetary carrier. The sliding engagement assembly of the clutch mechanism is arranged in the transmission housing so as to be non-rotatable relative to the transmission housing but axially slidable relative to the transmission housing. The sliding engagement assembly can be positioned in three positions during axial sliding: a first position in which the ring gear is engaged with the sliding engagement assembly, preventing the ring gear from rotating relative to the transmission housing while the planetary carrier is freely rotatable relative to the transmission housing; a second position in which the planetary carrier is engaged with the sliding engagement assembly, preventing the planetary carrier from rotating relative to the transmission housing while the ring gear is freely rotatable relative to the transmission housing; and a third position in which neither the ring gear nor the planetary carrier is engaged with the sliding engagement assembly, allowing the ring gear and the planetary carrier to rotate freely relative to the transmission housing.

[0025] Therefore, the electric bridge drive system according to the present invention utilizes the axial sliding of the sliding engagement assembly of the clutch mechanism to selectively position the electric bridge drive system in three different states. Not only is the clutch mechanism relatively simple and cost-effective, it also does not significantly affect the overall layout of the electric bridge drive system and can achieve desired functions such as connecting or disconnecting the transmission connection between the vehicle's wheels and the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 FIG. 1 is a schematic cross-sectional view of an electric bridge drive system according to an embodiment of the present invention, taken along an axial direction and including a central axis.

[0027] Figures 2a to 2c Shown respectively Figure 1 Schematic diagram of the enlarged area M of the electric bridge drive system in FIG, wherein the sliding engagement components of the clutch mechanism in each figure are in three different positions.

[0028] Description of Reference Numerals

[0029] EM motor SA input shaft

[0030] SU sun gear PL double planetary gear PL1 first planetary gear PL2 second planetary gear R ring gear P planetary gear carrier

[0031] H transmission housing H1 step part CU limit assembly

[0032] S clutch mechanism S1 sliding member S2 actuator S3 first engaging member S4 second engaging member T1 inner teeth T2 first outer teeth T3 second outer teeth

[0033] DM differential HS1 first half shaft HS2 second half shaft

[0034] AX is axial and RA is radial. DETAILED DESCRIPTION

[0035] The following describes exemplary embodiments of the present invention with reference to the accompanying drawings. It should be understood that these specific descriptions are only used to teach those skilled in the art how to implement the present invention, and are not intended to exhaust all possible embodiments of the present invention, nor to limit the scope of the present invention.

[0036] In the present invention, "transmission connection" refers to the connection between two components that can transmit driving force / torque. Unless otherwise specified, it can mean that the two components are directly connected or connected via a transmission structure such as a gear mechanism to transmit driving force / torque between the two components. In addition, in the present invention, "axial" and "radial" refer to the axial and radial directions of the input shaft of the transmission, respectively, and "axial side" refers to the Figure 1 The left side in the figure is the side where the motor is located, and the other side of the axis is Figure 1 to the right of the camcorder, opposite to the motor.

[0037] (Structure of an Electric Bridge Drive System According to One Embodiment of the Present Invention)

[0038] like Figure 1 As shown, the electric bridge drive system according to one embodiment of the present invention includes an electric motor EM, a transmission, a differential DM and two half-shafts assembled together.

[0039] In this embodiment, the motor EM is arranged axially to one side relative to the transmission. The motor EM may be a conventional motor having a stator and a rotor located radially inside the stator, the rotor being rotatable relative to the stator and outputting torque.

[0040] In this embodiment, the transmission includes a hollow input shaft SA, a double planetary gear mechanism, a clutch mechanism S, a limit assembly CU and a transmission housing H.

[0041] It should be understood that the component SA can be expressed as either the input shaft of the transmission or the output shaft of the motor EM. Whether the component SA is classified as belonging to the motor EM or the transmission does not affect the technical concept of the present invention and is within the scope of the present invention.

[0042] Specifically, the input shaft SA of the transmission is arranged coaxially with the rotor of the motor EM, and the input shaft SA is connected to the rotor in a manner that is non-rotatable relative to the rotor of the motor EM, so that when the rotor of the motor EM outputs torque, the input shaft SA can always rotate along with the rotor of the motor EM, thereby receiving torque from the rotor of the motor EM.

[0043] Furthermore, the double planetary gear mechanism is located radially outside the input shaft SA of the transmission, and the double planetary gear includes a sun gear SU, a plurality of double planetary gears PL (each double planetary gear PL includes a first planetary gear PL1 and a second planetary gear PL2 formed as one body), a ring gear R and a planetary gear carrier P.

[0044] The sun gear SU is coaxially arranged with the input shaft SA and is non-rotatably provided on the input shaft SA so that the sun gear SU can always rotate along with the input shaft SA and receive torque from the input shaft SA.

[0045] The multiple duplex planetary gears PL are located radially outward from the sun gear SU. The sun gear SU is constantly meshed with the first planetary gears PL1 of the multiple duplex planetary gears PL. The second planetary gears PL2 of the multiple duplex planetary gears PL are constantly meshed with the ring gear R. The first planetary gears PL1 are axially positioned to the side of the second planetary gears PL2. In practice, as long as each first planetary gear PL1 rotates with its corresponding second planetary gear PL2, it is not necessary for the first planetary gears PL1 and the corresponding second planetary gear PL2 to be integrally formed or rigidly connected.

[0046] A plurality of double planetary gears PL are mounted on a planetary gear carrier P, which is transmission-connected to a differential DM.

[0047] The ring gear R is located radially outward of the multiple duplex planetary gears PL and is always in meshing engagement with the second planetary gear PL2 of the multiple duplex planetary gears PL. The ring gear R is always fixed relative to the transmission housing H in the axial direction AX by the limiter assembly CU and the step portion H1 of the transmission housing H.

[0048] In this embodiment, the clutch mechanism S includes a sliding member S1 , an actuator S2 , a first engaging member S3 , and a second engaging member S4 .

[0049] Specifically, the sliding member S1 can take the form of a sliding sleeve, formed with a plurality of internal teeth T1, which are used to selectively engage with the first external teeth T2 of the first engaging member S3 fixed to the ring gear R or the second external teeth T3 of the second engaging member S4 provided on the planetary gear carrier P, thereby enabling the sliding member S1 to selectively engage with the ring gear R or the planetary gear carrier P. The actuator S2 can take the form of a shift fork, which can drive the sliding member S1 to slide in the axial direction AX. The sliding engagement assembly including both the sliding member S1 and the actuator S2 as a whole can slide in the axial direction AX relative to the transmission housing H but cannot rotate relative to the transmission housing H. The sliding engagement assembly is located axially on the other side of the ring gear R and radially outward of the planetary gear carrier P.

[0050] Furthermore, a first engaging member S3 is fixed to the other axial surface of the ring gear R, for example, by welding or other means. The first engaging member S3 is formed with a plurality of first external teeth T2 for engaging with the plurality of internal teeth T1 of the slider S1. A second engaging member S4 is fixedly mounted on the planetary carrier P in a manner fixedly secured to the planetary carrier P. The second engaging member S4 is formed with a plurality of second external teeth T3 for engaging with the plurality of internal teeth T1 of the slider S1. The second external teeth T3 are spaced apart from the first external teeth T2 in the axial direction AX, but are co-located with the first external teeth T2 in the radial direction RA.

[0051] By adopting the clutch mechanism S of the above structure, as Figures 2a to 2c As shown, the sliding joint assembly can be in the following first position (ie, working position, as shown in FIG. Figure 2a As shown), the second position (i.e. the parking position, as shown Figure 2c As shown) and the third position (i.e., the neutral position, as shown Figure 2b shown).

[0052] Reference Figure 1 and Figure 2aIn the first position, the multiple first external teeth T2 of the first engagement member S3 fixed to the ring gear R engage the multiple internal teeth T1 of the sliding engagement assembly S1, preventing the ring gear R from rotating relative to the transmission housing H. At this point, torque from the electric motor EM can be transmitted normally via the transmission input shaft SA and the duplex planetary gear mechanism to the differential DM, thereby driving the vehicle normally. The torque transmission path at this point is as follows: electric motor EM → input shaft SA → sun gear SU → duplex planetary gears PL → planetary carrier P → differential DM → two half-shafts HS1 and HS2.

[0053] Reference Figure 1 and Figure 2c In the second position, the plurality of second external teeth T3 of the second engagement member S4 provided on the planetary wheel carrier P engage with the plurality of internal teeth T1 of the sliding member S1 of the sliding engagement assembly, so that the planetary wheel carrier P cannot rotate relative to the transmission housing H. At this time, the vehicle realizes the parking function, and the vehicle's half-shafts HS1 and HS2 cannot rotate.

[0054] Reference Figure 1 and Figure 2b In the third position, neither the first engagement member S3 fixed to the ring gear R nor the second engagement member S4 provided on the planetary carrier P engages with the sliding member S1 of the sliding engagement assembly, thereby enabling both the ring gear R and the planetary carrier P to rotate relative to the transmission housing H. At this point, the internal tooth T1 of the sliding member S1 is located in the axial direction AX between the first internal tooth T1 of the first engagement member S3 and the second internal tooth T1 of the second engagement member S4. The entire transmission is in neutral, and torque from the electric motor EM is not transmitted to the differential DM. Rotation of the two half-shafts HS1 and HS2 (i.e., the wheels) does not affect the electric motor EM.

[0055] In this embodiment, the housing of the differential DM is fixedly mounted on the planetary carrier P of the double planetary gear mechanism, preventing rotation relative to the planetary carrier P. This allows torque from the planetary carrier P to be transmitted to the two half-shafts HS1 and HS2. The differential DM is integrated into the transmission housing H. Two half-shafts HS1 and HS2 extend axially from the differential DM. The first half-shaft HS1 extends axially from the differential DM to one side, passing through the hollow input shaft SA of the transmission and rotatable independently of the input shaft SA. The second half-shaft HS2 extends axially from the differential DM to the other side. This allows torque from the electric motor EM to be transmitted via the transmission to the differential DM, and then to the vehicle's half-shafts HS1 and HS2, ultimately to the wheels.

[0056] Furthermore, the transmission housing H is formed with a radially inwardly convex stepped portion H1. The electric axle drive system further includes a stopper assembly CU mounted on the transmission housing H and located axially to one side of the stepped portion H1. The stopper assembly CU includes a snap ring and a washer that abut against each other in the axial direction AX. The washer also abuts against the ring gear R from one axial side, causing the ring gear R to abut against the stepped portion H1 from the other axial side. Thus, the stopper assembly CU and the stepped portion H1 clamp a portion of the ring gear R in the axial direction AX, thereby preventing the ring gear R from moving relative to the transmission housing H in the axial direction AX.

[0057] In addition, the present invention also provides a vehicle including the electric bridge drive system of the above structure. The vehicle can be a pure electric vehicle or a hybrid vehicle.

[0058] The technical solution of the present invention has been described in detail in the above specific embodiments, and supplementary explanations are given below.

[0059] i. Although not explicitly described in the above specific embodiments, it should be understood that the clutch mechanism S of the electric bridge drive system according to the present invention makes very little change to the overall structural layout of the existing electric bridge drive system and does not require additional installation space.

[0060] In addition, since the clutch mechanism S is provided, the transmission can be placed in neutral position through the clutch mechanism S when the vehicle speed is too fast, so that the wheels cannot actively drag the motor EM, thereby avoiding the problem of motor EM failure caused by excessive vehicle speed.

[0061] ii. Although not explicitly stated in the above specific embodiments, it should be understood that the actuator S2 of the clutch mechanism S can be actuated by other driving sources (eg, another motor not shown).

[0062] iii. In the above embodiment, the differential DM and the two half-shafts HS1 and HS2 are integrated into the transmission housing H, which facilitates a compact structure of the entire electric axle drive system. However, the present invention is not limited to this embodiment; the differential DM and / or the two half-shafts HS1 and HS2 may be independent of the transmission as needed.

Claims

1. A bridge drive system, characterized in that: The electric bridge drive system includes: Electric machines (EM); and A transmission, comprising an input shaft (SA), a planetary gear mechanism, a clutch mechanism (S), and a housing (H); the input shaft (SA) is drivingly coupled to the electric motor (EM); the planetary gear mechanism comprises a sun gear (SU), a plurality of planetary gears (PL), a planetary gear carrier (P), and a ring gear (R); the sun gear (SU) is drivingly coupled to the input shaft (SA); the planetary gear carrier (P) is used to transmit torque to the outside of the planetary gear mechanism; The clutch mechanism (S) includes a sliding engagement assembly, which is arranged on the housing (H) in a manner such that it cannot rotate relative to the housing (H) of the transmission but can slide relative to the housing (H) in the axial direction (AX) of the electric bridge drive system. The sliding engagement assembly can be in the following three positions in the axial direction (AX): a first position in which the ring gear (R) is engaged with the sliding joint assembly so that the ring gear (R) cannot rotate relative to the housing (H); a second position in which the planet wheel carrier (P) is engaged with the sliding joint assembly so that the planet wheel carrier (P) cannot rotate relative to the housing (H); and a third position, in which the ring gear (R) and the planetary carrier (P) are not engaged with the sliding joint assembly, so that the ring gear (R) and the planetary carrier (P) are both able to rotate relative to the housing (H).

2. The electric bridge drive system according to claim 1, characterized in that: The sliding engagement assembly includes a sliding member (S1) and an actuator (S2) assembled together, wherein the sliding member (S1) is used to selectively engage with the ring gear (R) or the planetary gear carrier (P), and the actuator (S2) can drive the sliding member (S1) to slide in the axial direction (AX).

3. The electric bridge drive system according to claim 2, characterized in that: The sliding member (S1) is formed with a plurality of internal teeth (T1), The clutch mechanism (S) also includes a first engaging member (S3) and a second engaging member (S4), wherein the first engaging member (S3) is arranged on the ring gear (R) in a manner that cannot rotate relative to the ring gear (R), and the first engaging member (S3) is formed with a plurality of first external teeth (T2) for engaging with the plurality of internal teeth (T1), and the second engaging member (S4) is arranged on the planetary gear carrier (P) in a manner that cannot rotate relative to the planetary gear carrier (P), and the second engaging member (S4) is formed with a plurality of second external teeth (T3) for engaging with the plurality of internal teeth (T1).

4. The electric bridge drive system according to claim 3, characterized in that: The plurality of first external teeth (T2) and the plurality of second external teeth (T3) are spaced apart in the axial direction (AX) so that in the first position the plurality of internal teeth (T1) are engaged with the plurality of first external teeth (T2), in the second position the plurality of internal teeth (T1) are engaged with the plurality of second external teeth (T3), and in the third position the plurality of internal teeth (T1) are located between the plurality of first external teeth (T2) and the plurality of second external teeth (T3) in the axial direction (AX).

5. The electric bridge drive system according to any one of claims 1 to 4, characterized in that: The ring gear (R) is located between the step portion (H1) of the housing (H) and a limiting assembly (CU) installed on the housing (H), so that the ring gear (R) is fixed relative to the housing (H) in the axial direction (AX).

6. The electric bridge drive system according to any one of claims 1 to 4, characterized in that: The sliding joint assembly is driven by another motor to move in the axial direction (AX).

7. The electric bridge drive system according to any one of claims 1 to 4, characterized in that: The planetary gear mechanism is a double planetary gear mechanism, the planetary gear (PL) includes a first planetary gear (PL1) and a second planetary gear (PL2) fixed to each other in a coaxial manner, the first planetary gear (PL1) and the sun gear (SU) are always in meshing state, the second planetary gear (PL2) and the ring gear (R) are always in meshing state, and the first planetary gear (PL1) and the second planetary gear (PL2) are both mounted on the planetary gear carrier (P).

8. The electric bridge drive system according to any one of claims 1 to 4, characterized in that: The rotor of the electric motor (EM) is mounted on the input shaft (SA) in a coaxial manner with the input shaft (SA).

9. The electric bridge drive system according to any one of claims 1 to 4, characterized in that: The electric bridge drive system also includes a differential (DM) and two half-shafts (HS1, HS2) extending from the differential (DM) toward both axial sides. The planetary wheel carrier (P) is drivingly connected to the differential (DM). The two half-shafts (HS1, HS2) are coaxially arranged with the input shaft (SA), and the input shaft (SA) is a hollow shaft, so that one of the two half-shafts (HS1, HS2) passes through the input shaft (SA) and can rotate independently of the input shaft (SA).

10. A vehicle, characterized in that: The vehicle includes the electric axle drive system according to any one of claims 1 to 9.

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