CN210637485U

CN210637485U - Speed reduction transmission device of pure electric vehicle

Info

Publication number: CN210637485U
Application number: CN201920790961.5U
Authority: CN
Inventors: 梁道明
Original assignee: Chongqing Dongba Technology Co ltd
Current assignee: Chongqing Dongba Technology Co ltd
Priority date: 2019-05-29
Filing date: 2019-05-29
Publication date: 2020-05-29
Anticipated expiration: 2029-05-29

Abstract

A speed reduction transmission device of a pure electric vehicle comprises a hydraulic oil pump and a shell, wherein the shell is supported by an input shaft and a rotating shaft through a bearing, a high-speed driving gear and a low-speed driving gear are circumferentially fixed on the input shaft, a high-speed driven gear and a low-speed driven gear are sleeved on the rotating shaft in an empty manner, the high-speed driving gear is meshed with the high-speed driven gear, the low-speed driving gear is meshed with the low-speed driven gear, a synchronizer and an output gear are circumferentially fixed on the rotating shaft, an input gear of a differential mechanism supported on the shell is meshed with the output gear, the left end of the input shaft extends out of the shell and is supported on a box body, the output driving gear is circumferentially fixed at the left end of the input shaft, the right end of the box body is fixed with the shell, an output driven gear is sleeved on an output, the left end of the output shaft is fixed with the driving shaft of the hydraulic oil pump in the circumferential direction, and the pump shell of the hydraulic oil pump is fixed with the left end of the box body.

Description

Speed reduction transmission device of pure electric vehicle

Technical Field

The utility model relates to a pure electric vehicle field, in particular to speed reduction transmission of pure electric vehicle.

Background

With the requirement of environmental protection, the development of pure electric vehicles in the field of motor vehicles is accelerated. In general, a final drive of a pure electric vehicle outputs drive power only to wheels by decelerating the drive power. However, with the development of the pure electric vehicle, the requirement for additional auxiliary functions of the pure electric vehicle is also increased, for example, the electric vehicle needs to be added with an automatic unloading function, a lifting hydraulic cylinder needs to be arranged to push a container to turn over, hydraulic oil for driving the lifting hydraulic cylinder to work is provided by a hydraulic oil pump, power of the hydraulic oil pump needs to be driven by a motor, a motor is generally specially arranged for a vehicle with the lifting hydraulic cylinder to drive a hydraulic oil pump to work, the lifting hydraulic cylinder is arranged on the pure electric vehicle in such a way, two motors need to be arranged to respectively drive the vehicle to run and drive the hydraulic oil pump to work, and the power consumption of a battery needs to be increased when the two motors work, so that the cruising ability of the pure electric vehicle is seriously affected, and a lot of inconvenience is. And the layout of the vehicle is also influenced by the installation of the two motors, the design difficulty of the vehicle is increased, and the manufacturing cost is also increased.

Disclosure of Invention

The utility model aims at prior art not enough, provide a speed reduction transmission of electricelectric motor car, job stabilization is effective, it can through a motor drive, reduced the power consumption of battery, prolonged the continuation of the journey mileage, optimized the overall arrangement of vehicle.

The technical scheme of the utility model is that: a speed reduction transmission device of a pure electric vehicle comprises a hydraulic oil pump and a shell, wherein the shell is provided with an input shaft and a rotating shaft which are parallel to each other through a bearing support, the right end of the input shaft extends out of the shell and is used for connecting a motor, the input shaft circumferentially fixes a high-speed driving gear and a low-speed driving gear from right to left in sequence, the rotating shaft is sleeved with a high-speed driven gear and a low-speed driven gear in an air-to-air mode, the high-speed driving gear is meshed with the high-speed driven gear, the low-speed driving gear is meshed with the low-speed driven gear, a synchronizer and an output gear are circumferentially fixed on the rotating shaft and are positioned between the low-speed driven gear and the high-speed driven gear, the shell supports a differential mechanism through a bearing, the input gear and the output gear of the differential mechanism are meshed and are, the fixed output driving gear of this end circumference, the box right-hand member is connected fixedly with the casing, support an output shaft parallel with the input shaft through the bearing in the box, an output driven gear of output shaft free sleeve, this output driven gear and output driving gear meshing, output driven gear one end sets up the combination tooth, fixed and an axial sliding fit combination gear of output shaft circumference, the combination gear is used for meshing or separating with output driven gear's combination tooth by first shift fork drive, the fixed hydraulic oil pump that is used for output power drive of output shaft left end and hydraulic oil pump's drive shaft circumference, the hydraulic oil pump case is connected fixedly with the box left end.

The left end shaft center of the output shaft is provided with a spline hole, the end part of the driving shaft of the hydraulic oil pump is provided with a spline shaft extending axially, and the spline shaft is inserted into the spline hole of the output shaft to form circumferential fixed connection between the output shaft and the driving shaft.

The output shaft is installed in an axial sliding fit mode through the spline circumferential fixed combination gear and the combination gear.

And a ring groove matched with the first shifting fork is formed in the outer circumference of the combination gear.

The left end of low-speed driven gear sets up the low-speed combination tooth, and the right-hand member of high-speed driven gear sets up the high-speed combination tooth, low-speed combination tooth, high-speed combination tooth correspond with the combination facing of synchronous ware respectively, the combination facing is driven by the second shift fork, the combination tooth hub and the pivot circumference of synchronous ware are fixed.

The input shaft is circumferentially fixed with the high-speed driving gear and the output driving gear through splines, the input shaft and the low-speed driving gear are of an integrated structure, and spline teeth connected with a motor are arranged at the right end of the input shaft.

The combination tooth of output driven gear is the external tooth, and the combination gear is the internal tooth, or the combination tooth of output driven gear is the internal tooth, and the combination gear is the external tooth, or the combination tooth of output driven gear and combination gear are the face tooth.

The rotating shaft and the output gear are of an integrated structure.

The hydraulic oil pump is fixedly connected with the left end of the box body through a connecting plate.

The differential mechanism comprises a left half shaft gear, a right half shaft gear, an upper planetary gear and a lower planetary gear, wherein the two half shaft gears are in meshing transmission with the two planetary gears respectively, the two planetary gears are fixedly connected with a differential mechanism shell, the differential mechanism shell is fixedly connected with an input gear, and the two half shaft gears are connected with wheels through half shafts respectively to output power.

Adopt above-mentioned technical scheme: the hydraulic oil pump comprises a hydraulic oil pump and a shell, wherein the shell is supported by an input shaft and a rotating shaft which are parallel to each other through a bearing, the right end of the input shaft extends out of the shell and is used for connecting a motor, the input shaft is sequentially and circumferentially fixed with a high-speed driving gear and a low-speed driving gear from right to left, a high-speed driven gear and a low-speed driven gear are sleeved on the rotating shaft, the high-speed driving gear is meshed with the high-speed driven gear, the low-speed driving gear is meshed with the low-speed driven gear, a synchronizer and an output gear are circumferentially fixed on the rotating shaft, the synchronizer is positioned between the low-speed driven gear and the high-speed driven gear, the shell supports a differential mechanism through the bearing, the input gear and the output gear of the differential mechanism are meshed for outputting power to drive wheels to rotate, the shell extending, the box right-hand member is connected fixedly with the casing, support an output shaft parallel with the input shaft through the bearing in the box, an output driven gear of output shaft free sleeve, this output driven gear and output driving gear meshing, output driven gear one end sets up the combination tooth, fixed and an axial sliding fit combination gear of output shaft circumference, the combination gear is used for meshing or separating with output driven gear's combination tooth by first shift fork drive, the output shaft left end is used for exporting power drive hydraulic oil pump with the drive shaft circumference of hydraulic oil pump is fixed, the hydraulic oil pump case is connected fixedly with the box left end. The device works stably and effectively, and the main speed reducer and the hydraulic oil pump are driven by the same motor. When the synchronous device works, the combined gear sleeve of the synchronizer is firstly controlled to be meshed with the high-speed driven gear or the low-speed driven gear. The motor rotating shaft drives the input shaft to rotate, the high-speed driving gear and the low-speed driving gear start to rotate simultaneously, the high-speed driving gear drives the high-speed driven gear to rotate, and the low-speed driving gear drives the low-speed driven gear to rotate. The high-speed driven gear and the low-speed driven gear drive the rotating shaft to rotate through the synchronizer, if a combination gear sleeve of the synchronizer is combined with the high-speed driven gear, high-speed transmission is achieved, and if the combination gear sleeve is combined with the low-speed driven gear, low-speed transmission is achieved. The rotation of the output gear on the rotating shaft can drive the input gear of the differential mechanism to rotate, and the input gear drives the differential mechanism to work so as to output power to drive wheels of the vehicle to rotate. Meanwhile, the left end of the input shaft extends out of the shell and outputs power through the output driving gear. The output driving gear rotates to drive the output driven gear to rotate, the combination gear is controlled to be meshed with the combination teeth of the output driven gear through the first shifting fork, the combination gear drives the output shaft to rotate, and the driving shaft of the hydraulic oil pump is driven by the output shaft to rotate to drive the hydraulic oil pump to work. Therefore, the device can simultaneously drive the wheels to rotate and the hydraulic oil pump to work, so that the main speed reducer and the hydraulic oil pump are integrated, the overall layout of the vehicle is facilitated, and the processing and the assembly of the vehicle are facilitated. And the device can be driven by a motor, not only reduces the power consumption of the battery, prolongs the endurance mileage of the vehicle, but also reduces the vehicle parts, reduces the design difficulty, optimizes the vehicle structure and has low manufacturing cost of the vehicle. Meanwhile, the power input into the hydraulic oil pump by the device is stable and reliable, and the working stability of the lifting hydraulic cylinder is ensured. And through the output driving gear and the output driven gear that set up, increased the arrangement space of hydraulic oil pump, its is more nimble with being connected of casing, has avoided hydraulic oil pump and other spare parts of electricelectric motor car to take place the condition of interfering.

The left end shaft center of the output shaft is provided with a spline hole, the end part of the driving shaft of the hydraulic oil pump is provided with a spline shaft extending axially, and the spline shaft is inserted into the spline hole of the output shaft to form circumferential fixed connection between the output shaft and the driving shaft. The spline shaft is well matched with the spline hole, the circumferential limiting is stable and effective, and the assembly of the output shaft and the driving shaft is simple.

The output shaft is installed in an axial sliding fit mode through the spline circumferential fixed combination gear and the combination gear, the spline forms circumferential limiting on the combination gear, axial sliding of the combination gear can be guaranteed, and the combination gear and the output shaft are simple to assemble.

The outer circumference of the combination gear is provided with a ring groove matched with the first shifting fork, and the ring groove forms axial limiting between the combination gear and the first shifting fork, so that effective shifting of the first shifting fork to the combination gear is guaranteed.

The left end of low-speed driven gear sets up the low-speed combination tooth, and the right-hand member of high-speed driven gear sets up the high-speed combination tooth, low-speed combination tooth, high-speed combination tooth correspond with the combination facing of synchronous ware respectively, the combination facing is driven by the second shift fork, the combination tooth hub and the pivot circumference of synchronous ware are fixed. The high-speed and low-speed conversion can be realized by shifting the combination gear sleeve through the second shifting fork, during high-speed transmission, the combination gear sleeve of the synchronizer is combined with the high-speed combination gear of the high-speed driven gear, and during low-speed transmission, the combination gear sleeve is combined with the low-speed combination gear of the low-speed driven gear.

The input shaft circumferentially fixes the high-speed driving gear and the output driving gear through the spline, and the input shaft and the low-speed driving gear are of an integrated structure. The input shaft and the low-speed driving gear are integrated, so that the assembly is more convenient, and the assembly procedures are reduced. The right end of the input shaft is provided with spline teeth connected with the motor, and the spline teeth are connected with the motor, so that the connection is simple, quick, stable and effective.

The combination tooth of output driven gear is the external tooth, and the combination gear is the internal tooth, or the combination tooth of output driven gear is the internal tooth, and the combination gear is the external tooth, or the combination tooth of output driven gear and combination gear are the face tooth. The combination teeth of the output driven gear and the combination gear can be effectively meshed through the meshing of the inner teeth and the outer teeth or the meshing of the end face teeth, and the transmission is stable and reliable.

The rotating shaft and the output gear are of an integrated structure, the integrated structure is more stable, and the assembly of the rotating shaft is simplified.

The hydraulic oil pump is fixedly connected with the left end of the box body through the connecting plate, the connecting plate enables the structure of the hydraulic oil pump shell to be simpler, the machining of the hydraulic oil pump shell is simplified, and the connection between the hydraulic oil pump and the box body is better.

The differential mechanism comprises a left half shaft gear, a right half shaft gear, an upper planetary gear and a lower planetary gear, wherein the two half shaft gears are in meshing transmission with the two planetary gears respectively, the two planetary gears are fixedly connected with a differential mechanism shell, the differential mechanism shell is fixedly connected with an input gear, and the two half shaft gears are connected with wheels through half shafts respectively to output power. The differential case is supported on the case through a bearing, and the right and left driving wheels of the vehicle can rotate at different rotating speeds through the differential, so that the normal running of the vehicle is ensured.

The speed reduction transmission device of the pure electric vehicle is simple to assemble and stable and reliable in transmission, integrates the main speed reducer and the hydraulic oil pump together, optimizes the overall layout of the vehicle and facilitates the processing and assembly of the vehicle. And the power consumption of the battery is reduced, the endurance mileage of the pure electric vehicle is prolonged, vehicle parts are reduced, and the vehicle structure is optimized. And the hydraulic oil pump has large arrangement space and more flexible connection with the shell, and avoids the interference between the hydraulic oil pump and other parts of the vehicle.

The invention is further described with reference to the drawings and the specific embodiments.

Drawings

Fig. 1 is a schematic structural view of the present invention;

in the attached drawing, 1 is a shell, 2 is a connecting plate, 3 is an output shaft, 4 is an output driven gear, 4-1 is a combination gear, 5 is a combination gear, 6 is a first shifting fork, 7 is an output driving gear, 8 is a box body, 9 is an input shaft, 10 is a low-speed driving gear, 11 is a high-speed driving gear, 12 is a low-speed driven gear, 12-1 is a low-speed combination gear, 13 is a second shifting fork, 14 is a synchronizer, 14-1 is a combination gear sleeve, 15 is a high-speed driven gear, 15-1 is a high-speed combination gear, 16 is an output gear, 17 is a rotating shaft, 18 is a differential, 18-1 is an input gear, 18-2 is a half shaft gear, 18-3 is a planetary gear, 19 is a hydraulic oil pump, 19-1 is a driving shaft, and 19-2 is a spline shaft.

Detailed Description

Referring to fig. 1, the speed reduction transmission device of the pure electric vehicle comprises a hydraulic oil pump 19 and a shell 1, wherein the shell 1 supports an input shaft 9 and a rotating shaft 17 which are parallel to each other through a bearing. The right end of the input shaft 9 extends out of the shell 1 to be connected with the motor, the shaft section of the right end of the input shaft 9 extending out of the shell 1 is provided with spline teeth connected with the motor, and the motor is connected through the spline teeth, so that the connection is simple, rapid, stable and effective. The input shaft 9 is sequentially and circumferentially fixed with a high-speed driving gear 11 and a low-speed driving gear 10 from right to left, and a high-speed driven gear 15 and a low-speed driven gear 12 are sleeved on the rotating shaft 17 in an overhead manner. The high-speed driving gear 11 is engaged with the high-speed driven gear 15, and the low-speed driving gear 10 is engaged with the low-speed driven gear 12. Synchronizer 14, output gear 16 are fixed to the last circumference of pivot 17, pivot 17 and output gear 16 structure as an organic whole, and integrative structure is more stable, has also simplified the assembly of pivot 17. The synchronizer 14 is located between the low-speed driven gear 12 and the high-speed driven gear 15. The left end of the low-speed driven gear 12 is provided with a low-speed combination tooth 12-1, the right end of the high-speed driven gear 15 is provided with a high-speed combination tooth 15-1, the low-speed combination tooth 12-1 and the high-speed combination tooth 15-1 respectively correspond to a combination gear sleeve 14-1 of the synchronizer 14, the combination gear sleeve 14-1 is driven by a second shifting fork 13, an annular groove matched with the second shifting fork 13 is formed in the combination gear sleeve 14-1, and a combination gear hub of the synchronizer 14 is circumferentially fixed with the rotating shaft 17. The high-speed and low-speed conversion can be realized by shifting the combining gear sleeve 14-1 through the second shifting fork 13, during high-speed transmission, the combining gear sleeve 14-1 of the synchronizer 14 is combined with the high-speed combining gear 15-1 of the high-speed driven gear 15, and during low-speed transmission, the combining gear sleeve 14-1 is combined with the low-speed combining gear 12-1 of the low-speed driven gear 12. The shell 1 supports a differential 18 through a bearing, the differential 18 comprises an input gear 18-1, a left half shaft gear 18-2, a right half shaft gear 18-2, an upper planet gear 18-3 and a lower planet gear 18-3, the input gear 18-1 of the differential 18 is meshed with the output gear 16, the two half shaft gears 18-2 are respectively meshed with the two planet gears 18-3 for transmission, the two planet gears 18-3 are fixedly connected with a differential 18 shell, the differential 18 shell is fixedly connected with the input gear 18-1, and the two half shaft gears 18-2 are respectively connected with wheels through half shafts to output power to drive the wheels to rotate. The differential 18 shell is supported on the shell 1 through a bearing, and the right and left driving wheels of the automobile can rotate at different rotating speeds through the differential 18, so that the normal running of the automobile is ensured. The differential 18, the input gear 18-1, the output gear 16, the synchronizer 14, the high-speed driven gear 15, the low-speed driven gear 12, the high-speed driving gear 11 and the low-speed driving gear 10 are all located in an inner cavity of the shell 1. The left end of the input shaft 9 extends out of the shell 1 and is supported on a box body 8 through a bearing, the box body 8 is formed by connecting a left part and a right part through bolts, the shell 1 covers an inner cavity through a shell cover, and an output driving gear 7 is circumferentially fixed on a shaft section of the left end of the input shaft 9 extending out of the shell 1. The output driving gear 7 and the high-speed driving gear 11 are both fixedly connected with the input shaft 9 in the circumferential direction through splines, the low-speed driving gear 10 and the input shaft 9 are of an integrated structure, the input shaft 9 and the low-speed driving gear 10 are of an integrated structure, assembly is facilitated, and assembly procedures are reduced. The right end of the box body 8 is fixedly connected with the outer side wall of the left end of the shell 1 through a bolt, an output shaft 3 parallel to the input shaft 9 is supported in the box body 8 through a bearing, an output driven gear 4 is sleeved in the output shaft 3 in an empty mode, and the output driven gear 4 is meshed with an output driving gear 7. The output driven gear 4 one end sets up and combines tooth 4-1, output shaft 3 passes through spline circumference fixed and axial sliding fit a combination gear 5, and the spline has both formed the circumference spacing to combination gear 5, also can guarantee the axial slip of combination gear 5, and the assembly of combination gear 5 and output shaft 3 is also simple. The coupling gear 5 is driven by a first fork 6 for engagement with or disengagement from the coupling teeth 4-1 of the output driven gear 4. The combined teeth 4-1 of the output driven gear 4 are external teeth, the combined gear 5 is internal teeth, or the combined teeth 4-1 of the output driven gear 4 are internal teeth, and the combined gear 5 is external teeth, or the combined teeth 4-1 of the output driven gear 4 and the combined gear 5 are both end face teeth. The combination teeth 4-1 of the output driven gear 4 and the combination gear 5 can realize effective meshing between the output driven gear 4 and the combination gear 5 through meshing of inner teeth and outer teeth or meshing of end face teeth, and the transmission is stable and reliable. In the present embodiment, the coupling gear 4-1 of the output driven gear 4 is selected to be an internal gear, and the coupling gear 5 is selected to be an external gear. The outer circumference of the combination gear 5 is provided with a ring groove matched with the first shifting fork 6, and the ring groove forms axial limit between the combination gear 5 and the first shifting fork 6, so that effective shifting of the first shifting fork 6 to the combination gear 5 is guaranteed. The left end shaft center of the output shaft 3 is provided with a spline hole, the end part of a driving shaft 19-1 of the hydraulic oil pump 19 is provided with an axially extending spline shaft 19-2, and the spline shaft 19-2 is inserted into the spline hole of the output shaft 3 to circumferentially connect the output shaft 3 with the driving shaft 19-1 to fix the output power and drive the hydraulic oil pump 19. The spline shaft 19-2 is well matched with the spline hole, the circumferential limit is stable and effective, and the assembly of the output shaft 3 and the driving shaft 19-1 is simple. 19 shell of hydraulic oil pump is connected fixedly through connecting

plate

2 and 8 left ends of box, and connecting plate 2 can make the structure of 19 shells of hydraulic oil pump simpler, has simplified the processing of 19 shells of hydraulic oil pump, and the connection of 19 shells of hydraulic oil pump and box is also better.

The device works stably and effectively, and the main speed reducer and the hydraulic oil pump 19 are driven by the same motor. When the synchronous device works, the engaging gear sleeve 14-1 of the synchronizer 14 is firstly controlled to be meshed with the high-speed engaging gear 15-1 of the high-speed driven gear 15 or the low-speed engaging gear 12-1 of the low-speed driven gear 12. The motor shaft drives the input shaft 9 to rotate, meanwhile, the high-speed driving gear 11 and the low-speed driving gear 10 start to rotate, the high-speed driving gear 11 drives the high-speed driven gear 15 to rotate, and the low-speed driving gear 10 drives the low-speed driven gear 12 to rotate. The high-speed driven gear 15 and the low-speed driven gear 12 both drive the rotating shaft 17 to rotate through the synchronizer 14, if the engaging gear sleeve 14-1 of the synchronizer 14 is engaged with the high-speed engaging gear 15-1, high-speed transmission is performed, and if the engaging gear sleeve 14-1 is engaged with the low-speed engaging gear 12-1, low-speed transmission is performed. Rotation of the output gear 16 on the shaft 17 rotates the input gear 18-1 of the differential 18, and the input gear 18-1 drives the differential 18 to operate to output power to drive the wheels of the vehicle to rotate. Meanwhile, the left end of the input shaft 9 extends out of the housing 1 and outputs power through the output driving gear 7. The output driving gear 7 rotates to drive the output driven gear 4 to rotate, the first shifting fork 6 controls the combination gear 5 to be meshed with the combination teeth 4-1 of the output driven gear 4, the combination gear 5 drives the output shaft 3 to rotate, and the output shaft 3 drives the driving shaft 19-1 of the hydraulic oil pump 19 to rotate to drive the hydraulic oil pump 19 to work. Therefore, the device can simultaneously drive the wheels to rotate and the hydraulic oil pump 19 to work, so that the main speed reducer and the hydraulic oil pump 19 are integrated, the overall layout of the vehicle is facilitated, and the processing and the assembly of the vehicle are facilitated. And the device can be driven by a motor, not only reduces the power consumption of the battery, prolongs the endurance mileage of the vehicle, but also reduces the vehicle parts, reduces the design difficulty, optimizes the vehicle structure and has low manufacturing cost of the vehicle. Meanwhile, the power input into the hydraulic oil pump 19 by the device is stable and reliable, and the working stability of the lifting hydraulic cylinder is ensured. In addition, the arrangement space of the hydraulic oil pump 19 is increased through the arranged output driving gear 7 and the output driven gear 4, the connection between the hydraulic oil pump and the shell 1 is more flexible, and the situation that the hydraulic oil pump 19 interferes with other parts of the pure electric vehicle is avoided.

Claims

1. The utility model provides a speed reduction transmission of electricelectric motor car, includes hydraulic oil pump (19), casing (1), its characterized in that: casing (1) has input shaft (9), pivot (17) that are parallel to each other through the bearing support, input shaft (9) right-hand member extends casing (1) and is used for connecting the motor, fixed high-speed driving gear (11), low-speed driving gear (10) of circumference are in proper order from right to left in input shaft (9), the sky cover has high-speed driven gear (15), low-speed driven gear (12) in pivot (17), high-speed driving gear (11) and high-speed driven gear (15) meshing, low-speed driving gear (10) and low-speed driven gear (12) meshing, fixed synchronizer (14), output gear (16) of circumference on pivot (17), synchronizer (14) are located between low-speed driven gear (12), high-speed driven gear (15), casing (1) are through a bearing support differential mechanism (18), input gear (18-1) and output gear (16) meshing of differential mechanism (18) are used for exporting power The driving wheel rotates, the left end of the input shaft (9) extends out of the shell (1) and is supported on a box body (8) through a bearing, an output driving gear (7) is fixed to the left end in the circumferential direction, the right end of the box body (8) is connected and fixed with the shell (1), an output shaft (3) parallel to the input shaft (9) is supported in the box body (8) through a bearing, an output driven gear (4) is sleeved on the output shaft (3) in a hollow mode, the output driven gear (4) is meshed with the output driving gear (7), a combination tooth (4-1) is arranged at one end of the output driven gear (4), the output shaft (3) is fixed in the circumferential direction and is axially matched with a combination gear (5) in a sliding mode, the combination gear (5) is driven by a first shifting fork (6) and is used for being meshed with or separated from the combination tooth (4-1) of the output driven gear (4), and the left end of the output shaft (3) is fixed And a hydraulic oil pump (19) is driven by output power, and a shell of the hydraulic oil pump (19) is fixedly connected with the left end of the box body (8).

2. The pure electric vehicle reduction transmission device according to claim 1, wherein: the left end shaft center of the output shaft (3) is provided with a spline hole, the end part of a driving shaft (19-1) of the hydraulic oil pump (19) is provided with a spline shaft (19-2) extending axially, and the spline shaft (19-2) is inserted into the spline hole of the output shaft (3) to form circumferential fixed connection between the output shaft (3) and the driving shaft (19-1).

3. The pure electric vehicle reduction transmission device according to claim 1, wherein: the output shaft (3) is installed in an axial sliding fit mode through a spline circumferential fixed combination gear (5) and the combination gear (5).

4. The pure electric vehicle reduction transmission device according to claim 1, wherein: and a ring groove matched with the first shifting fork (6) is formed in the outer circumference of the combination gear (5).

5. The pure electric vehicle reduction transmission device according to claim 1, wherein: the left end of low-speed driven gear (12) sets up low-speed combination tooth (12-1), and the right-hand member of high-speed driven gear (15) sets up high-speed combination tooth (15-1), low-speed combination tooth (12-1), high-speed combination tooth (15-1) correspond with combination tooth cover (14-1) of synchronous ware (14) respectively, combination tooth cover (14-1) are driven by second shift fork (13), the combination tooth hub and pivot (17) circumference of synchronous ware (14) are fixed.

6. The pure electric vehicle reduction transmission device according to claim 1, wherein: the input shaft (9) is circumferentially fixed with the high-speed driving gear (11) and the output driving gear (7) through splines, the input shaft (9) and the low-speed driving gear (10) are of an integrated structure, and spline teeth connected with a motor are arranged at the right end of the input shaft (9).

7. The pure electric vehicle reduction transmission device according to claim 1, wherein: the combined gear (4-1) of the output driven gear (4) is an external gear, the combined gear (5) is an internal gear, or the combined gear (4-1) of the output driven gear (4) is an internal gear, the combined gear (5) is an external gear, or the combined gear (4-1) and the combined gear (5) of the output driven gear (4) are both end face teeth.

8. The pure electric vehicle reduction transmission device according to claim 1, wherein: the rotating shaft (17) and the output gear (16) are of an integral structure.

9. The pure electric vehicle reduction transmission device according to claim 1, wherein: the hydraulic oil pump (19) is fixedly connected with the left end of the box body (8) through the connecting plate (2).

10. The pure electric vehicle reduction transmission device according to claim 1, wherein: the differential mechanism (18) comprises a left half shaft gear, a right half shaft gear (18-2), an upper planet gear and a lower planet gear (18-3), the two half shaft gears (18-2) are respectively in meshed transmission with the two planet gears (18-3), the two planet gears (18-3) are fixedly connected with a differential mechanism (18) shell, the differential mechanism (18) shell is fixedly connected with an input gear (18-1), and the two half shaft gears (18-2) are respectively connected with wheels through half shafts to output power.