A three-gear transmission power transmission system for a pure electric heavy commercial vehicle

Abstract

The application discloses a kind of pure electric heavy commercial vehicle three-gear transmission axle power transmission systems, including drive motor, transmission, reducer and differential;The transmission is composed of three parallel shafts, four sets of gear pairs and two sets of gear shifting actuators;The first shaft includes coaxially arranged first shaft section and second shaft section, the first shaft section is connected with the output shaft end of drive motor, the first shaft section is provided with combination tooth A, and the combination tooth A is engaged with the second shaft section;Four sets of gear pairs are gear pair I, gear pair II, gear pair III and gear pair IV respectively;Two sets of gear shifting actuators are the first set of gear shifting actuators and the second set of gear shifting actuators respectively;By adopting three parallel shafts, four sets of gear pair mechanisms and two sets of gear shifting actuators, a high-integration multi-stage three-gear transmission is formed, which realizes a large speed ratio while having the advantages of short axial width, small motor front suspension, compact structure, light weight and space saving.

Description

Technical Field

[0001] This invention belongs to the field of new energy heavy-duty commercial vehicle technology, and relates to a three-speed transmission system for a pure electric heavy-duty commercial vehicle. Background Technology

[0002] There are three new types of electric axles in the power transmission system of new energy heavy commercial vehicles: hub motor, wheel-side motor, and mid-mounted motor drive axle. The above-mentioned electric drive axles generally use direct drive reduction, and the single-speed transmission needs to take into account both high and low speed performance, which places high demands on the performance of the motor. During low-speed driving, the motor's working efficiency is only 60% to 70%.

[0003] Currently, the power transmission systems commonly used in the market fall into two categories: one is a separate arrangement of the motor, transmission, drive shaft, and electric vehicle axle reducer assembly; the other is an integrated arrangement of the motor and a variable-speed reducer with an idler shaft. The former has more power transmission components, a longer transmission chain, lower transmission efficiency, larger size, and is more difficult to arrange; the latter, due to the presence of the idler shaft, is relatively difficult to arrange, has more gear transmission stages, and lower transmission efficiency. Therefore, there is significant room for improvement in the power transmission systems of electric drive axles for heavy-duty commercial vehicles. Summary of the Invention

[0004] The purpose of this invention is to provide a three-speed transmission system for pure electric heavy-duty commercial vehicles, which solves the problems of existing power transmission systems, such as multiple power transmission links, long transmission chains, low transmission efficiency, large size, and difficult layout.

[0005] The technical solution adopted in this invention is a three-speed transmission system for a pure electric heavy-duty commercial vehicle, including a drive motor, a transmission, a reducer and a differential.

[0006] The transmission consists of three parallel shafts, four sets of gear pairs, and two sets of shift actuators;

[0007] The three parallel shafts are shaft I, shaft II, and shaft III, and shaft I includes shaft I segment and shaft II segment arranged coaxially. Shaft I segment is connected to the output shaft end of the drive motor. Shaft I segment is provided with engagement tooth A, which engages with shaft II segment.

[0008] The four gear pairs are gear pair I, gear pair II, gear pair III, and gear pair IV. Gear pair I includes a meshing driving gear ZⅠ1 and a driven gear ZⅠ2. Gear pair II includes a meshing driving gear ZⅡ1 and a driven gear ZⅡ2. Gear pair III includes a meshing driving gear ZⅢ1 and a driven gear ZⅢ2. Gear pair IV includes a meshing driving gear ZⅠ1 and a driven gear ZⅣ2. The driving gear ZⅠ1 is fixed on shaft I, and the driven gear ZⅠ2 is fixed on shaft II. The driving gear ZⅡ1 is fixed on shaft II, and the driven gear ZⅡ2 is loosely fitted on shaft II. The driven gear ZⅡ2 is also provided with a engagement tooth B. The driving gear ZⅢ1 is fixed on shaft II, and the driven gear ZⅢ2 is loosely fitted on shaft III. The driven gear ZⅢ2 is also provided with a engagement tooth C. The driven gear ZⅣ2 is loosely fitted on shaft III. The driven gear ZⅣ2 is also provided with a engagement tooth D.

[0009] The two sets of shift actuators are the first set of shift actuators and the second set of shift actuators;

[0010] The reducer includes a constant mesh gear pair, which includes a constant mesh driving gear and a constant mesh driven gear that mesh with each other. The constant mesh driving gear is fixed on the third shaft, and the constant mesh driven gear is fixed on the differential.

[0011] Furthermore, the first set of shifting actuators includes a splined hub I and a sliding engagement sleeve I; the second set of shifting actuators includes a splined hub II and a sliding engagement sleeve II. The splined hub I is fixed on the second shaft segment and arranged between the driving gear ZⅠ1 and the driven gear ZⅡ2, and the sliding engagement sleeve I is slidably connected to the splined hub I; the splined hub II is fixed on the third shaft and arranged between the driven gear ZⅢ2 and the driven gear ZⅣ2, and the sliding engagement sleeve II is slidably connected to the splined hub II.

[0012] Furthermore, the drive motor and the driving gear ZⅠ1 of gear pair I are coaxially arranged.

[0013] Furthermore, gear pairs I, II, III, IV and the constant meshing gear pairs are all external meshing gear pairs, and the gears are all helical cylindrical gears.

[0014] The beneficial effects of this invention are:

[0015] This invention relates to the design of a multi-speed transmission system for pure electric heavy-duty commercial vehicles. By adopting a highly integrated multi-stage three-speed transmission composed of three parallel shafts, four sets of gear pairs, and two sets of shifting actuators, it achieves a large speed ratio while having the advantages of short axial width, small motor front overhang, compact structure, light weight, and space saving. Moreover, it reduces the number of parts, has high transmission efficiency, high shifting efficiency, and fast speed adjustment response, thus ensuring high reliability and achieving optimal cost. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the three-speed transmission axle power transmission system for a pure electric heavy-duty commercial vehicle according to the present invention;

[0017] Figure 2 This is a schematic diagram of the first power transmission route of the three-speed transmission axle power transmission system for pure electric heavy-duty commercial vehicles according to the present invention.

[0018] Figure 3 This is a schematic diagram of the second power transmission route of the three-speed transmission axle power transmission system for pure electric heavy-duty commercial vehicles of the present invention;

[0019] Figure 4 This is a schematic diagram of the third power transmission route of the three-speed transmission axle power transmission system for pure electric heavy-duty commercial vehicles according to the present invention;

[0020] In the diagram, 1. Drive motor, 2. Driven gear ZⅣ2, 3. Gear pair IV, 4. Driving gear ZⅠ1, 5. Shaft I, 6. Shaft segment I, 7. Engaging gear A, 8. Gear pair I, 9. Transmission, 10. Shaft II, 11. Driven gear ZⅠ2, 12. Driving gear ZⅡ1, 13. Gear pair II, 14. Sliding engagement sleeve I, 15. Engaging gear B, 16. Shaft segment II, 17. Driving gear ZⅢ1, 18. Splined hub I 19. Gear pair III, 20. First set of shifting actuator, 21. Driven gear ZⅡ2, 22. Splined hub II, 23. Driven gear ZⅢ2, 24. Engaging gear C, 25. Sliding meshing sleeve II, 26. Second set of shifting actuator, 27. Engaging gear D, 28. Constant mesh driven gear, 29. Reducer, 30. Differential, 31. Half shaft, 32. Constant mesh gear pair, 33. Third shaft, 34. Constant mesh driving gear. Detailed Implementation

[0021] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0022] like Figure 1 As shown: A three-speed transmission system for a pure electric heavy-duty commercial vehicle includes a drive motor 1, a transmission 9, a reducer 29 and a differential 30.

[0023] The transmission 9 consists of three parallel shafts, four sets of gear pairs, and two sets of shift actuators;

[0024] The three parallel shafts are the first shaft 5, the second shaft 10 and the third shaft 33, and the first shaft 5 includes the first shaft segment 6 and the second shaft segment 16 arranged coaxially. The first shaft segment 6 is connected to the output shaft end of the drive motor 1. The first shaft segment 6 is provided with a engagement tooth A7, which engages with the second shaft segment 16.

[0025] The four gear pairs are respectively gear pair I 8, gear pair II 13, gear pair III 19 and gear pair IV 3; gear pair I 8 includes a driving gear ZI 14 and a driven gear ZI 211 that mesh with each other; gear pair II 13 includes a driving gear ZII 112 and a driven gear ZII 221 that mesh with each other; gear pair III 19 includes a driving gear ZIII 117 and a driven gear ZIII 223 that mesh with each other; gear pair IV 3 includes a driving gear ZI 14 and a driven gear ZIV 22 that mesh with each other; the driving gear ZI 14 is fixed on the first shaft section 6, and the driven gear ZI 211 is fixed on the second shaft 10; the driving gear ZII 112 is fixed on the second shaft 10, the driven gear ZII 221 is sleeved on the second shaft section 16, and the driven gear ZII 221 is also provided with engaging teeth B 15; the driving gear ZIII 117 is fixed on the second shaft section 16, the driven gear ZIII 223 is sleeved on the third shaft 33, and the driven gear ZIII 223 is also provided with engaging teeth C 24; the driven gear ZIV 22 is sleeved on the third shaft 33, and the driven gear ZIV 22 is also provided with engaging teeth D 27.

[0026] The two shift actuators are respectively the first set of shift actuator 20 and the second set of shift actuator 26;

[0027] The reducer 29 includes a constant mesh gear pair 32, the constant mesh gear pair 32 includes a constant mesh driving gear 34 and a constant mesh driven gear 28 that mesh with each other, the constant mesh driving gear 34 is fixed on the third shaft 33, and the constant mesh driven gear 28 is fixed on the differential 30.

[0028] The first set of shift actuator 20 includes a spline hub I 18 and a sliding engagement sleeve I 14; the second set of shift actuator 26 includes a spline hub II 22 and a sliding engagement sleeve II 25. The spline hub I 18 is fixed on the second shaft section 16 and is arranged between the driving gear ZI 14 and the driven gear ZII 221, and the sliding engagement sleeve I 14 is slidably connected to the spline hub I 18; the spline hub II 22 is fixed on the third shaft 33 and is arranged between the driven gear ZIII 223 and the driven gear ZIV 22, and the sliding engagement sleeve II 25 is slidably connected to the spline hub II 22.

[0029] The drive motor 1 and the driving gear ZI 14 of the gear pair I 8 are coaxially arranged.

[0030] The gear pair I 8, gear pair II 13, gear pair III 19, gear pair IV 3 and the constant mesh gear pair 32 are all external meshing gear pairs, and the gears are all helical cylindrical gears.

[0031] The mutually combined shifting actions are performed by the shifting actuator. The power output by the driving motor is adjusted in terms of speed and torque through the transmission, achieving multi-stage three-speed shifting and transmitting the power to the reducer. After further reducing the speed and increasing the torque, the reducer transmits the power to the differential. The two output ends of the differential output the power to the two half shafts, and the half shafts transmit the power to the wheels connected thereto, thereby driving the vehicle to travel.

[0032] As Figure 2 shown, for the three-speed power transmission system, the first transmission route is as follows: the sliding engaging sleeve I 14 of the first set of shifting actuators 20 moves to the left and engages with the engaging tooth B15 of the driven gear ZII221 of the gear pair II 13. The sliding engaging sleeve II 25 of the second set of shifting actuators 26 moves to the left and engages with the engaging tooth C24 of the driven gear ZIII223 of the gear pair III 19. The driving gear ZII112 and the driven gear ZII221 of the gear pair II 13 transmit power, and the driving gear ZIII117 and the driven gear ZIII223 of the gear pair III 19 transmit power. The power output by the driving motor 1 is transmitted to the reducer 29 through the gear pair I 8, the gear pair II 13, and the gear pair III 19. After further reducing the speed and increasing the torque, the reducer 29 transmits the power to the differential 30 and then outputs the power, ultimately achieving four-stage deceleration;

[0033] As Figure 3 shown, for the three-speed power transmission system, the second transmission route is as follows: the sliding engaging sleeve I 14 of the first set of shifting actuators 20 moves to the right and engages with the engaging tooth A7 of the first shaft section 6. The sliding engaging sleeve II 25 of the second set of shifting actuators 26 moves to the left and engages with the engaging tooth C24 of the driven gear ZIII223 of the gear pair III 19. The first shaft section 6 and the second shaft section 16 rotate synchronously, and the driving gear ZIII117 and the driven gear ZIII223 of the gear pair III 19 transmit power. The power output by the driving motor 1 is transmitted to the reducer 29 through the gear pair III 19. After further reducing the speed and increasing the torque, the reducer 29 transmits the power to the differential 30 and then outputs the power, ultimately achieving two-stage deceleration;

[0034] As Figure 4As shown, in the three-speed transmission system, the third transmission route is as follows: the sliding engagement sleeve I14 of the first set of shift actuators 20 is set not to mesh with the engagement tooth A7 of the first shaft segment 6 and the engagement tooth B15 of the driven gear ZⅡ221 of the gear pair II 13. The sliding engagement sleeve II25 of the second set of shift actuators 26 moves to the right and meshes with the engagement tooth D27 of the driven gear ZⅣ22 of the gear pair IV 3. The driving gear ZⅠ14 and the driven gear ZⅣ22 of the gear pair IV 3 transmit power. The power output by the drive motor 1 is transmitted to the reducer 29 through the gear pair IV 3. The reducer 29 further reduces speed and increases torque before transmitting power to the differential 30 and outputting power, ultimately achieving two-stage reduction.

Claims

1. A three-speed transmission system for a pure electric heavy-duty commercial vehicle, characterized in that, It includes a drive motor (1), a transmission (9), a reducer (29), and a differential (30); The transmission (9) consists of three parallel shafts, four sets of gear pairs and two sets of shifting actuators; The three parallel shafts are the first shaft (5), the second shaft (10) and the third shaft (33), and the first shaft (5) includes the first shaft segment (6) and the second shaft segment (16) arranged coaxially. The first shaft segment (6) is connected to the output shaft end of the drive motor (1). The first shaft segment (6) is provided with a engagement tooth A (7), which engages with the second shaft segment (16). The four gear pairs are gear pair I (8), gear pair II (13), gear pair III (19) and gear pair IV (3); gear pair I (8) includes the meshing driving gear ZⅠ1 (4) and driven gear ZⅠ2 (11); Gear pair II (13) includes a driving gear ZⅡ1 (12) and a driven gear ZⅡ2 (21) meshing with each other; gear pair III (19) includes a driving gear ZⅢ1 (17) and a driven gear ZⅢ2 (23) meshing with each other; gear pair IV (3) includes a driving gear ZⅠ1 (4) and a driven gear ZⅣ2 (2) meshing with each other; the driving gear ZⅠ1 (4) is fixed on the first shaft segment (6), and the driven gear ZⅠ2 (11) is fixed on the second shaft (10); the driving gear ZⅡ1 (12) is fixed on On the second shaft (10), the driven gear ZⅡ2 (21) is loosely fitted on the second shaft section (16), and the driven gear ZⅡ2 (21) is also provided with engagement teeth B (15); the driving gear ZⅢ1 (17) is fixed on the second shaft section (16), the driven gear ZⅢ2 (23) is loosely fitted on the third shaft (33), and the driven gear ZⅢ2 (23) is also provided with engagement teeth C (24); the driven gear ZⅣ2 (2) is loosely fitted on the third shaft (33), and the driven gear ZⅣ2 (2) is also provided with engagement teeth D (27); The two sets of shift actuators are the first set of shift actuators (20) and the second set of shift actuators (26); The reducer (29) includes a constant mesh gear pair (32), which includes a constant mesh driving gear (34) and a constant mesh driven gear (28) that mesh with each other. The constant mesh driving gear (34) is fixed on the third shaft (33), and the constant mesh driven gear (28) is fixed on the differential (30).

2. The three-speed transmission system for a pure electric heavy-duty commercial vehicle according to claim 1, characterized in that, The first set of shifting actuators (20) includes a splined hub I (18) and a sliding engagement sleeve I (14); the second set of shifting actuators (26) includes a splined hub II (22) and a sliding engagement sleeve II (25); the splined hub I (18) is fixed on the second shaft segment (16) and arranged between the driving gear ZⅠ1 (4) and the driven gear ZⅡ2 (21), and the sliding engagement sleeve I (14) is slidably connected to the splined hub I (18); the splined hub II (22) is fixed on the third shaft (33) and arranged between the driven gear ZⅢ2 (23) and the driven gear ZⅣ2 (2), and the sliding engagement sleeve II (25) is slidably connected to the splined hub II (22).

3. The three-speed transmission system for a pure electric heavy-duty commercial vehicle according to claim 1, characterized in that, The drive motor (1) and the driving gear ZⅠ1 (4) of the gear pair Ⅰ (8) are coaxially arranged.

4. The three-speed transmission system for a pure electric heavy-duty commercial vehicle according to claim 1, characterized in that, The gear pairs I (8), II (13), III (19), IV (3) and constant meshing gear pairs (32) are all external meshing gear pairs, and the gears are all helical cylindrical gears.

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