Vehicle electric drive system and vehicle

Abstract

The invention provides a vehicle electric drive system and a vehicle, and relates to the field of vehicle parts, the vehicle electric drive system and the vehicle comprise a speed reducer and a brake, the speed reducer comprises an input gear, a fixed gear and an output gear, the input gear and the fixed gear are coaxially arranged, and the brake is used for being installed on an electric drive shell and used for being combined with the fixed gear; the output gear is located on the outer side of the input gear and the outer side of the fixed gear, the output gear is a duplicate gear, and two gears of the output gear are meshed with the input gear and the fixed gear respectively. Compared with an existing speed reducer with an inner gear ring, the design of the inner gear ring is omitted, the machining problem of the tooth surface of the inner gear ring does not need to be considered, the machining difficulty is small, the machining precision is high, the machining quality of the speed reducer or an electric drive system is better guaranteed, and the problem that the inner gear ring and an electric drive shell are abraded due to spline fit of the inner gear ring and the electric drive shell does not exist; the input gear and the fixed gear are coaxially arranged, and the space occupied by the speed reducer, namely the whole electric drive system, is small.

Description

Technical Field

[0001] The present invention relates to the field of vehicle parts, and in particular to a vehicle electric drive system and a vehicle. Background Art

[0002] With the rapid development of automobiles, especially new energy vehicles, people have put forward higher requirements on the service life and processing quality of their electric drive systems. The electric drive system usually uses a reducer with an inner gear ring, such as an input gear, a first inner gear ring and a second inner gear ring. The first inner gear ring is fixed on the electric drive housing, and the motor is connected to the input gear drive. The input gear is a double gear. One of the gears of the double gear is meshed with the first inner gear ring, and the other gear is meshed with the second inner gear ring. The second inner gear ring is used as the output end to realize the power transmission of the motor. First, an inner gear ring is required. The tooth surface of the inner gear ring is difficult to process and the processing accuracy is low, which makes the processing quality of the reducer or the electric drive system low. Second, the outer peripheral wall of the inner gear ring is fixed to the electric drive housing through spline matching. When the hardness difference between the two is large and the inner gear ring is subjected to multi-directional forces, the inner gear ring and the electric drive housing are very easy to wear, which makes the service life of the electric drive system low. Summary of the invention

[0003] The present invention aims to solve the technical problems of low processing quality and low service life of the existing electric drive system.

[0004] On the one hand, the present invention provides a vehicle electric drive system, including a reducer and a brake, the reducer including an input gear, a fixed gear and an output gear, the input gear and the fixed gear are coaxially arranged, the brake is used to be installed on the electric drive housing and to be combined with the fixed gear, the output gear is located on the outside of the input gear and the fixed gear, the output gear is a double gear, and the two gears of the output gear are respectively meshed with the input gear and the fixed gear.

[0005] Optionally, the input gear, the fixed gear and two gears of the output gear are all helical gears.

[0006] Optionally, the vehicle electric drive system further comprises a motor, a motor shaft of which is coaxially and fixedly connected to the input gear.

[0007] Optionally, the reducer further includes a fixed shaft, the fixed shaft is movably sleeved on the outside of the motor shaft, the fixed shaft is coaxially fixedly connected to the fixed gear, and the brake is used to be combined with the fixed shaft.

[0008] Optionally, the vehicle electric drive system also includes a planetary carrier and a differential. Along the extension direction of the motor shaft, the differential and the brake are respectively located on both sides of the reducer, and the differential is located on the side of the reducer away from the motor. The output gear of the reducer is transmission-connected to the differential through the planetary carrier, and the planetary carrier is rotationally connected to the electric drive housing.

[0009] Optionally, the differential includes a first sun gear, a second sun gear, a first planetary gear and a second planetary gear, the first sun gear and the second sun gear are both coaxially arranged with the input gear, the first planetary gear and the second planetary gear are both movably mounted on the planetary carrier, the second planetary gear is located on the outer side of the second sun gear and meshes with the second sun gear, and the first planetary gear is located on the outer side of the second planetary gear and the first sun gear, and meshes with the second planetary gear and the first sun gear respectively.

[0010] Optionally, the first sun gear, the second sun gear, the first planet gears and the second planet gears are all spur gears.

[0011] Optionally, the planetary carrier includes a plurality of connecting frames arranged around the first sun gear and the second sun gear, the connecting frames include a first connecting shaft, a connecting part and a second connecting shaft connected in sequence, the output gear and the first planetary gear are both movably mounted on the first connecting shaft, the second connecting shaft is parallel to the first connecting shaft, and the second planetary gear is movably mounted on the second connecting shaft.

[0012] Optionally, the interior of the motor shaft is provided with a through hole extending through the motor shaft along its axial direction, and the vehicle electric drive system also includes two half-shafts, one of which passes through the through hole and has its two ends respectively connected to the first sun gear and the first wheel, and the other half-shaft has its two ends respectively connected to the second sun gear and the second wheel.

[0013] On the other hand, the present invention provides a vehicle, comprising the above-mentioned vehicle electric drive system.

[0014] The vehicle electric drive system and vehicle of the present invention have at least the following advantages compared to the prior art:

[0015] The input gear of the reducer can be connected to a driving mechanism such as a motor. When the brake is combined with the fixed gear, the fixed gear is relatively fixed to the electric drive housing, and the driving force output by the motor shaft of the motor is transmitted to the input gear of the reducer. Since the output gear is a double gear, and its two gears are respectively engaged with the input gear and the fixed gear, the output gear can rotate stably around the fixed gear driven by the input gear, thereby realizing power output. Compared with the reducer with an internal gear ring, the output gear of the present invention is located on the outside of the fixed gear and the input gear, and the two gears of the output gear are respectively meshed with the fixed gear and the output gear, that is, the two gears of the output gear, the input gear and the fixed gear are all external gears, thus eliminating the design of the internal gear ring and the need to consider the processing of the tooth surface of the internal gear ring. Only ordinary external tooth surface gears need to be processed, which is less difficult and more accurate. The processing quality of the reducer or the electric drive system is more guaranteed, and there is no wear problem of the internal gear ring and the electric drive housing caused by the spline matching of the internal gear ring and the electric drive housing, so the service life of the electric drive system is longer. In addition, the input gear and the fixed gear are coaxially arranged, so the space occupied by the reducer, that is, the electric drive system as a whole, is smaller. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of a vehicle electric drive system according to an embodiment of the present invention.

[0017] Description of reference numerals:

[0018] 1. Reducer; 11. Input gear; 12. Fixed gear; 13. Output gear; 131. Large gear; 132. Small gear; 14. Fixed shaft; 2. Brake; 3. Motor shaft; 31. Through hole; 4. Planetary carrier; 41. Connecting frame; 411. First connecting shaft; 412. Connecting part; 413. Second connecting shaft; 5. Differential; 51. First sun gear; 52. Second sun gear; 53. First planetary gear; 54. Second planetary gear; 6. Half shaft; 7. Bearing. DETAILED DESCRIPTION

[0019] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0020] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "matched" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] In addition, it should be noted that in the description of the present invention, it should be noted that the terminology nouns in the various embodiments, such as "upper", "lower", "front", "back" and other words indicating directions, are only for simplifying the description of the positional relationship based on the drawings in the specification, and do not mean that the referred elements and devices must be operated in accordance with the specific directions and defined operations and methods and structures in the specification. Such directional nouns do not constitute limitations on the present invention.

[0022] like Figure 1 As shown, a vehicle electric drive system according to an embodiment of the present invention includes a reducer 1 and a brake 2, wherein the reducer 1 includes an input gear 11, a fixed gear 12 and an output gear 13, wherein the input gear 11 is coaxially arranged with the fixed gear 12, the brake 2 is used to be installed on the electric drive housing and to be combined with the fixed gear 12, the output gear 13 is located on the outside of the input gear 11 and the fixed gear 12, the output gear 13 is a double gear, and the two gears of the output gear are respectively meshed with the input gear 11 and the fixed gear 12.

[0023] Specifically, the brake 2 is a prior art, which can be purchased directly and installed on the electric drive housing. The brake 2 is used to combine with the fixed gear 12 to keep the fixed gear 12 stationary relative to the electric drive housing. The input gear 11 can be connected to a driving mechanism, such as a motor, and the motor shaft 3 of the motor can be extended along the direction indicated by the Y axis, that is, the left and right direction of the vehicle. A plurality of output gears 13 can be arranged at intervals along the circumference of the input gear 11. The driving force transmitted to the input gear 11 by the driving mechanism can simultaneously drive multiple output gears 13 to rotate, thereby improving the stability of the power output. The output gear 13 is a double gear, which may include a large gear 131 and a small gear 132 arranged coaxially, the large gear 131 meshing with the input gear 11, and the small gear 132 meshing with the fixed gear 12.

[0024] In this embodiment, when the brake 2 is combined with the fixed gear 12, the fixed gear 12 and the electric drive housing can be relatively fixed, and the driving force output by the motor shaft 3 of the motor is transmitted to the input gear 11 of the reducer 1. Since the output gear 13 is a double gear, and its two gears are respectively engaged with the input gear 11 and the fixed gear 12, the output gear 13 can be driven by the input gear 11 to stably rotate around the fixed gear 12 and the input gear 11, thereby realizing power output. Compared with the existing reducer with an internal gear ring, in this embodiment, since the output gear 13 is located on the outside of the fixed gear 12 and the input gear 11, and the two gears of the output gear 13 are respectively meshed with the fixed gear 12 and the input gear 11, that is, the two gears of the output gear 13, the input gear 11 and the fixed gear 12 are all external gears, the design of the internal gear ring is omitted, and there is no need to consider the processing problem of the tooth surface of the internal gear ring. Only ordinary external tooth surface gears need to be processed, which has low processing difficulty and high processing accuracy. The processing quality of the reducer or the electric drive system is more guaranteed, and there is no wear problem of the internal gear ring and the electric drive housing caused by the spline matching of the internal gear ring and the electric drive housing, and the service life of the reducer or the electric drive system is longer; in addition, the input gear and the fixed gear are coaxially arranged, and the space occupied by the reducer, that is, the electric drive system as a whole, is smaller.

[0025] Optionally, the two gears of the input gear 11, the fixed gear 12 and the output gear 13 are all helical gears. Compared with the meshing of spur gears, the meshing of helical gears has a larger contact area of ​​the tooth surface, and the contact occurs gradually during meshing, which reduces the impact and vibration, and the transmission process is smoother. Here, the two gears of the input gear 11, the fixed gear 12 and the output gear 13 are helical gears, which can enhance the power transmission stability of the reducer 1, and is conducive to improving the NVH and durability of the electric drive system, wherein NVH refers to the comprehensive performance index of "noise, vibration and harshness".

[0026] like Figure 1 As shown, optionally, the reducer 1 further includes a fixed shaft 14 , which is movably sleeved on the outside of the motor shaft 3 , and the fixed shaft 14 is coaxially and fixedly connected to the fixed gear 12 , and the brake 2 is used to be combined with the fixed shaft 14 .

[0027] Specifically, the fixed shaft 14 is coaxially arranged with the motor shaft 3, that is, it is extended in the direction indicated by the Y axis. The interior of the fixed shaft 14 is hollow, and the fixed shaft 14 can be sleeved on the outside of the motor shaft 3. The movements of the two do not interfere with each other. One end of the fixed shaft 14 is fixed to the fixed gear 12. The brake 2 includes two parts for contacting and rubbing with each other, one of which is fixed on the electric drive housing, and the other is fixed on one end of the fixed shaft 14 away from the fixed gear 12. The two parts of the brake 2 are used for contact braking, so that the fixed gear 12 remains stationary.

[0028] In this embodiment, the fixed gear 12 can be conveniently coupled to the brake 2 on the electric drive housing through the fixed shaft 14. The fixed shaft 14 is sleeved outside the motor shaft 3 of the motor, which can save axial arrangement space.

[0029] like Figure 1 As shown, optionally, the vehicle electric drive system also includes a planetary carrier 4 and a differential 5. Along the extension direction of the motor shaft 3, the differential 5 and the brake 2 are respectively located on both sides of the reducer 1, and the differential 5 is located on the side of the reducer 1 away from the motor. The output gear 13 of the reducer 1 is transmission-connected to the differential 5 through the planetary carrier 4, and the planetary carrier 4 is rotationally connected to the electric drive housing.

[0030] Specifically, the planet carrier 4 can be rotatably connected to the electric drive housing through the bearing 7, the inner ring of the bearing 7 is interference fit with the planet carrier 4, and the outer ring of the bearing 7 is clearance fit with the electric drive housing. The output gear 13 of the reducer 1 rotates around the input gear 11, which can drive the planet carrier 4 to rotate around the input gear 11, thereby transmitting the driving force to the planet carrier 4. The planet carrier 4 can rotate relative to the electric drive housing. During the rotation process, the planet carrier 4 drives the planetary gear of the differential 5 to rotate around the sun gear to achieve power transmission.

[0031] The motor includes a motor body and a motor shaft 3, the brake 2 is located between the motor body and the reducer 1, and the differential 5 is located on the side of the reducer 1 away from the motor body, that is, the brake 2, the reducer 1 and the differential 5 are arranged in sequence along the extension direction of the motor shaft 3 to optimize the spatial layout and avoid interference between the differential 5 and the brake 2.

[0032] like Figure 1As shown, optionally, the differential 5 includes a first sun gear 51, a second sun gear 52, a first planetary gear 53 and a second planetary gear 54, the first sun gear 51 and the second sun gear 52 are both coaxially arranged with the input gear 11, the first planetary gear 53 and the second planetary gear 54 are both movably mounted on the planet carrier 4, the second planetary gear 54 is located on the outer side of the second sun gear 52 and meshes with the second sun gear 52, and the first planetary gear 53 is located on the outer side of the second planetary gear 54 and the first sun gear 51, and meshes with the second planetary gear 54 and the first sun gear 51 respectively.

[0033] Specifically, the size of the first sun gear 51 is larger than that of the second sun gear 52. The second sun gear 52 is coaxially arranged with the first sun gear 51, and the second sun gear 52 is located on one side of the first sun gear 51. The outer side of the second sun gear 52 can engage with multiple second planetary gears 54. The sum of the radius size of the second sun gear 52 and the diameter size of the second planetary gears 54 is equal to the radius size of the first sun gear 51, so that the outermost first planetary gear 53 can engage with the first sun gear 51 and the second planetary gear 54 at the same time.

[0034] The output gear 13 of the reducer 1 revolves around the input gear 11 to drive the planet carrier 4 to revolve around the input gear 11. Since the first sun gear 51 and the second sun gear 52 are both coaxially arranged with the input gear 11, the planet carrier 4 drives the first planet gear 53 and the second planet gear 54 to revolve around the first sun gear 51 and the second sun gear 52 during the rotation process. The first planet gear 53 and the second planet gear 54 also rotate on their own during the revolution process, thereby driving the first sun gear 51 and the second sun gear 52 to rotate smoothly. It should be noted that the first planet gear 53 has a larger size along its axial direction, that is, the circumferential tooth surface of the first planet gear 53 is longer, and can mesh with the first sun gear 51 and the second planet gear 54 at the same time.

[0035] The reducer 1 transmits the driving force to the first planetary gear 53 of the differential 5 through the planetary carrier 4. The driving force is then divided into two parts. One part drives the first sun gear 51 to rotate, and drives one of the wheels to rotate through the half shaft 6 corresponding to the first sun gear 51. The other part drives the second planetary gear 54 to rotate the second sun gear 52, and drives the other wheel to rotate through the half shaft 6 corresponding to the second sun gear 52, thereby realizing differential driving of the left and right wheels.

[0036] Optionally, the first sun gear 51 , the second sun gear 52 , the first planetary gears 53 and the second planetary gears 54 are all spur gears.

[0037] In this embodiment, the first sun gear 51, the second sun gear 52, the first planetary gear 53 and the second planetary gear 54 are all spur gears, and the first sun gear 51 and the second sun gear 52 are coaxially arranged, the first planetary gear 53 is located on the outside of the first sun gear 51 and the second sun gear 52, the first sun gear 51 is meshed with the first planetary gear 53, and the second sun gear 52 is meshed with the first planetary gear 53 through the second planetary gear 54, that is, the axis of the first planetary gear 53 is relatively parallel to the axis of the first sun gear 51 and the axis of the second sun gear 52. Compared with the existing bevel gear differential in which the axis of the planetary gear is perpendicular to the axis of the sun gear, the first sun gear 51 and the second sun gear 52 can be closer in the axial direction, thereby reducing the space occupied by the differential or the vehicle electric drive system as a whole along its axial direction, and the structure is more compact.

[0038] like Figure 1 As shown, optionally, the planetary carrier 4 includes a plurality of connecting frames 41 arranged around the first sun gear 51 and the second sun gear 52, the connecting frame 41 includes a first connecting shaft 411, a connecting portion 412 and a second connecting shaft 413 connected in sequence, the output gear 13 and the first planetary gear 53 are both movably mounted on the first connecting shaft 411, the second connecting shaft 413 is parallel to the first connecting shaft 411, and the second planetary gear 54 is movably mounted on the second connecting shaft 413.

[0039] Specifically, the planet carrier 4 is generally cylindrical, and includes a plurality of connecting frames 41 arranged at intervals along its own circumference, each connecting frame 41 corresponds to an output gear 13, a first planetary gear 53 and a second planetary gear 54, and the output gear 13, the first planetary gear 53 and the second planetary gear 54 are sleeved on the connecting frame 41, and can rotate around the connecting frame 41, and can also revolve around the straight line where the motor shaft 3 is located under the drive of the connecting frame 41. The connecting frame 41 can be a bent shape, so that the first planetary gear 53 and the second planetary gear 54 sleeved and fixed on the connecting frame 41 at the same time can be arranged on different axes, or to be more precise, the first planetary gear 53 can mesh with the second planetary gear 54.

[0040] The first connecting shaft 411 and the second connecting shaft 413 of the connecting frame 41 are arranged parallel to the motor shaft 3 and are both extended in the direction indicated by the Y axis. The second connecting shaft 413 is located between the first connecting shaft 411 of the corresponding connecting frame 41 and the motor shaft 3. One end of the first connecting shaft 411 passes through the output gear 13 and is rotatably connected to the electric drive housing through a bearing. The other end of the first connecting shaft 411 passes through the first planetary gear 53. The output gear 13 and the first planetary gear 53 are both sleeved on the first connecting shaft 411. The output gear 13 and the first planetary gear 53 can rotate around the first planetary gear 53. The connecting shaft 411 rotates on its own and can also revolve around the axis of the motor shaft 3 driven by the first connecting shaft 411; the first connecting shaft 411 passes through one end of the first planetary gear 53 and is connected to the second connecting shaft 413 via the connecting portion 412, and the second sun gear 52 is located on the side of the first sun gear 51 away from the motor body, and the second sun gear 52 is meshed with the second planetary gear 54, that is, the second planetary gear 54 is located on the side of the first sun gear 51 away from the motor body, so that the second planetary gear 54 can be easily fixed to the second connecting shaft 413, and the spatial arrangement is more reasonable.

[0041] like Figure 1 As shown, optionally, the interior of the motor shaft 3 is provided with a through hole 31 extending through the motor shaft 3 along its axial direction, and the vehicle electric drive system also includes two half-shafts 6, one of the half-shafts 6 passes through the through hole 31, and its two ends are respectively connected to the first sun gear 51 and the first wheel, and the other half-shaft 6 is respectively connected to the second sun gear 52 and the second wheel at both ends.

[0042] In this embodiment, one of the first and second wheels is the left wheel, and the other is the right wheel. Since the differential 5 is located on the side of the reducer 1 away from the motor, and the two sun gears of the differential 5 need to be connected to the left and right wheels through the corresponding half-axles, it is necessary to set a through hole 31 that penetrates along the axial direction of the motor shaft 3, so that the half-axle 6 connected to the first sun gear 51 can pass through the through hole 31 to connect to the first wheel, and the half-axle 6 connected to the second sun gear 52 can be directly connected to the second wheel to transmit the driving force of the differential 5 to the corresponding wheel to drive the wheel to run. Here, the motor shaft 3 is loosely sleeved on the outside of the corresponding half-axle 6 through the through hole 31, and the movements of the two do not interfere with each other. The half-axle 6 can be splined with the corresponding sun gear, and the assembly is simple.

[0043] Another embodiment of the present invention provides a vehicle, comprising the above-mentioned vehicle electric drive system. The vehicle is a new energy vehicle, and the advantages of the vehicle motor compared to the prior art are the same as those of the above-mentioned vehicle electric drive system, which will not be described again.

[0044] Although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A vehicle electric drive system, characterized in that: The invention comprises a reducer (1) and a brake (2), wherein the reducer (1) comprises an input gear (11), a fixed gear (12) and an output gear (13), wherein the input gear (11) and the fixed gear (12) are coaxially arranged, the brake (2) is used to be installed on an electric drive housing and to be combined with the fixed gear (12), the output gear (13) is located outside the input gear (11) and the fixed gear (12), the output gear (13) is a double gear, and the two gears of the output gear (13) are respectively meshed with the input gear (11) and the fixed gear (12).

2. The vehicle electric drive system according to claim 1, characterized in that: The input gear (11), the fixed gear (12) and the two gears of the output gear (13) are all helical gears.

3. The vehicle electric drive system according to claim 1, characterized in that: It also comprises a motor, wherein the motor shaft (3) of the motor is coaxially fixedly connected to the input gear (11).

4. The vehicle electric drive system according to claim 3, characterized in that: The reducer (1) also includes a fixed shaft (14), the fixed shaft (14) is movably sleeved on the outside of the motor shaft (3), the fixed shaft (14) is coaxially fixedly connected to the fixed gear (12), and the brake (2) is used to be combined with the fixed shaft (14).

5. The vehicle electric drive system according to claim 3, characterized in that: The invention also comprises a planet carrier (4) and a differential (5); along the extension direction of the motor shaft (3), the differential (5) and the brake (2) are respectively located on both sides of the reducer (1), and the differential (5) is located on the side of the reducer (1) away from the motor; the output gear (13) of the reducer (1) is transmission-connected to the differential (5) through the planet carrier (4), and the planet carrier (4) is rotationally connected to the electric drive housing.

6. The vehicle electric drive system according to claim 5, characterized in that: The differential (5) comprises a first sun gear (51), a second sun gear (52), a first planetary gear (53) and a second planetary gear (54); the first sun gear (51) and the second sun gear (52) are both coaxially arranged with the input gear (11); the first planetary gear (53) and the second planetary gear (54) are both movably sleeved on the planet carrier (4); the second planetary gear (54) is located on the outer side of the second sun gear (52) and meshes with the second sun gear (52); the first planetary gear (53) is located on the outer side of the second planetary gear (54) and the first sun gear (51), and meshes with the second planetary gear (54) and the first sun gear (51) respectively.

7. The vehicle electric drive system according to claim 6, characterized in that: The first sun gear (51), the second sun gear (52), the first planetary gear (53) and the second planetary gear (54) are all spur gears.

8. The vehicle electric drive system according to claim 6, characterized in that: The planetary carrier (4) comprises a plurality of connecting frames (41) arranged around the first sun gear (51) and the second sun gear (52); the connecting frame (41) comprises a first connecting shaft (411), a connecting portion (412) and a second connecting shaft (413) connected in sequence; the output gear (13) and the first planetary gear (53) are both movably sleeved on the first connecting shaft (411); the second connecting shaft (413) is parallel to the first connecting shaft (411); and the second planetary gear (54) is movably sleeved on the second connecting shaft (413).

9. The vehicle electric drive system according to claim 6, characterized in that: The motor shaft (3) is provided with a through hole (31) penetrating along its axial direction inside, and the vehicle electric drive system further comprises two half shafts (6), one of the half shafts (6) passes through the through hole (31), and two ends of the half shafts (6) are respectively connected to the first sun gear (51) and the first wheel, and two ends of the other half shaft (6) are respectively connected to the second sun gear (52) and the second wheel.

10. A vehicle, characterized in that: Comprising a vehicle electric drive system as described in any one of claims 1-9.

Images