CN218440587U

CN218440587U - Friction plate type two-gear speed reducer

Info

Publication number: CN218440587U
Application number: CN202222372705.9U
Authority: CN
Inventors: 张宇荣
Original assignee: Wenling Huaxin Machinery Manufacturing Co ltd
Current assignee: Wenling Huaxin Machinery Manufacturing Co ltd
Priority date: 2022-09-07
Filing date: 2022-09-07
Publication date: 2023-02-03
Anticipated expiration: 2032-09-07

Abstract

The utility model discloses a friction plate type two-gear speed reducer, which belongs to the technical field of speed reducers and comprises an input shaft, a first-gear driving gear, a second-gear driving gear and a gear shifting mechanism, wherein the first-gear driving gear is arranged on the input shaft through a one-way clutch, and the second-gear driving gear is sleeved on the input shaft in an idle mode; the gear shifting mechanism comprises a gear shifting friction pair and a gear shifting thrust structure, the gear shifting friction pair comprises a plurality of driving gear shifting friction plates and driven gear shifting friction plates which are arranged at intervals, the driving gear shifting friction plates are connected with the input shaft, the driven gear shifting friction plates are at least indirectly connected with two driving gears, and the gear shifting thrust structure can compress the driving gear shifting friction plates and the driven gear shifting friction plates to enable the two driving gears to be locked with the input shaft to realize gear shifting. The utility model not only can take into account the dynamic property and the economical efficiency of the electric vehicle, reduce the energy consumption of the motor, prolong the service life, but also reduce the noise, the vibration and the part loss when the electric vehicle runs at high speed; and the gear shifting process has no power interruption, the gear shifting impact is small, and the gear shifting device has no pause and frustration.

Description

Friction plate type two-gear speed reducer

Technical Field

The utility model relates to a two keep off the reduction gear, especially a friction plate formula two keep off reduction gear belongs to reduction gear technical field.

Background

The development and application of new energy vehicles become development hotspots of the industry in the future. The rotating speed range of the driving motor is wider, generally about 0-18000 r/min, even up to 20000r/min, so that the single-stage speed reducer can meet the requirements of realizing large-torque driving at low rotating speed and realizing high-speed running of vehicles at high rotating speed, and the current global mainstream pure electric vehicles adopt a framework that the driving motor is matched with the single-stage speed reducer.

Although the single-stage speed reducer is simple in structure and low in cost, the single transmission ratio of the single-stage speed reducer cannot simultaneously take power performance and economy of a pure electric vehicle into consideration, and the driving motor cannot work in a high-efficiency area all the time, so that the motor is high in energy consumption and low in service life, and the whole vehicle is poor in climbing, starting capability and high-speed performance. In addition, when the vehicle runs at a high speed, the motor needs to maintain an extremely high rotating speed, which brings mechanical problems such as noise, vibration and the like, and causes great loss to parts of the speed reducer.

Therefore, in order to improve the electric driving efficiency and balance the cost of the motor and the battery, the electric vehicle uses a two-gear speed reducer as a main trend in the future.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that overcome above-mentioned problem, and provide a friction plate formula two keep off reduction gear, can provide two sets of speed reduction ratios, compromise the dynamic property and the economic nature of electric motor car, reduce the motor energy consumption, increase of service life reduces noise, vibration and part loss when going at a high speed simultaneously.

The technical scheme of the utility model is that:

the utility model provides a friction plate formula two keep off reduction gear, includes retarder housing, input shaft subassembly, intermediate shaft subassembly, gearshift and output shaft, the input shaft subassembly holds the input shaft of locating in the retarder housing and locates one on the input shaft and keep off driving gear, two fender driving gears including rotating, the input shaft is connected with the driving motor of whole car, the intermediate shaft subassembly includes keeps off driven gear, two fender driven gear with the parallel jackshaft of input shaft and fixed connection are epaxial in the jackshaft, one keep off driven gear with one keeps off driving gear meshing transmission, two keep off driven gear with two fender driving gear meshing transmission, the intermediate shaft subassembly passes through reduction gears and is connected its characterized in that with output shaft transmission: the first-gear driving gear is installed on the input shaft through a one-way clutch, an inner ring of the one-way clutch is fixedly connected with the input shaft, an outer ring of the one-way clutch is fixedly connected with the first-gear driving gear, the one-way clutch is set to allow the first-gear driving gear to rotate forward relative to the input shaft, otherwise, the one-way clutch is locked, and the second-gear driving gear is freely sleeved on the input shaft through a bearing I; the gear shifting mechanism is arranged at the right section of the input shaft and comprises a gear shifting friction pair and a gear shifting thrust structure, the gear shifting friction pair comprises a plurality of driving gear shifting friction plates and driven gear shifting friction plates which are arranged at intervals and are coaxial with the input shaft, the driving gear shifting friction plates are connected with the input shaft, the driven gear shifting friction plates are at least indirectly connected with the two-gear driving gear, and the gear shifting thrust structure can compress the driving gear and the driven gear shifting friction plates of the gear shifting friction pair to lock the two-gear driving gear and the input shaft to realize gear shifting.

Set up one and keep off owner, driven gear and two keep off owner, driven gear, provide two sets of reduction ratios, enlarged the high-efficient interval of motor, guarantee the efficiency of the big moment of torsion acceleration in-process of electric motor car low rotational speed, can reduce driving motor's rotational speed through shifting when the vehicle is gone at a high speed again to promote driving motor's availability factor, reduce the motor energy consumption, increase of service life reduces noise, vibration and part loss when going at a high speed simultaneously.

Utilize one way clutch to realize surmounting formula and shift, the problem of power interrupt can not appear like traditional AMT mechanical transmission in the process of shifting, adopts wet-type friction disc gearshift simultaneously, and not only the impact of shifting is little, does not have the feeling of setback, and the noise is little moreover, long service life. And the whole setting of gearshift is in the right section of input shaft, and the variable speed of shifting can only be influenced in the trouble, can not influence the normal driving of vehicle.

Furthermore, in the friction plate type two-gear speed reducer, the gear shifting mechanism further comprises a gear shifting shell, the gear shifting shell is coaxially arranged with the input shaft, the gear shifting friction pair is arranged in the gear shifting shell and attached to the inner side of the left end part of the gear shifting shell, and a driven gear shifting friction plate of the gear shifting friction pair is connected with the gear shifting shell; the left end of the gear shifting shell axially extends to form a first spline hub with an internal spline, the right end of the second gear driving gear is formed with a second spline hub with an external spline, and the gear shifting shell and the second gear driving gear are meshed and connected through the first spline hub and the second spline hub, so that the driven gear shifting friction plate is indirectly connected with the second gear driving gear through the gear shifting shell.

Further, in the friction plate type two-gear speed reducer, the shifting thrust structure comprises a shifting actuator, a front guiding friction pair and a front guiding actuating assembly which are sequentially arranged on the right side of the shifting friction pair; the gear shifting actuator is a relative rotation actuator and comprises a first cam disc, a second cam disc and a plurality of rolling parts which are circumferentially arranged between the first cam disc and the second cam disc, the first cam disc is circumferentially and fixedly sleeved on the input shaft through spline connection and is adjacent to the gear shifting friction pair, the second cam disc is provided with an external spline, and the second cam disc is axially and fixedly sleeved on the input shaft; the opposite end surfaces of the first cam disc and the second cam disc are respectively provided with a plurality of circular arc-shaped track grooves distributed along the circumference, the depth of each track groove changes along the circumferential direction, each rolling part is clamped between one track groove of the first cam disc and one track groove of the second cam disc, and the two cam discs rotate relatively to enable the rolling parts to roll in the track grooves to enable the first cam discs to generate axial displacement; the front guide friction pair is sleeved between the second cam disc and the gear shifting shell and comprises a plurality of driving front guide friction plates and driven front guide friction plates which are arranged at intervals, the driving front guide friction plates are connected with the gear shifting shell, and the driven front guide friction plates are connected with the second cam disc; the pilot actuating assembly is used for driving the driving pilot friction plate and the driven pilot friction plate of the pilot friction pair to press against each other, so that the second cam plate of the gear shifting actuator is connected with the gear shifting shell and rotates relative to the first cam plate, and the first cam plate moves axially to press the driving shift friction plate and the driven shift friction plate of the gear shifting friction pair.

The two-stage transmission force application of the guide actuating assembly, the guide friction pair and the gear shifting actuator causes the two-gear driving gear to be locked with the input shaft to realize gear shifting, and a large locking force is obtained with low power consumption required for controlling the guide actuating assembly, and the gear shifting device is high in response speed and stable and reliable in performance.

Further, in the friction plate type two-gear speed reducer, the front guiding actuating assembly comprises an electromagnet arranged outside the right end face of the gear shifting shell, the electromagnet is fixed with the speed reducer shell, and the electrification of the electromagnet can enable the driving front guiding friction plate and the driven front guiding friction plate of the front guiding friction pair to be mutually pressed. The electromagnetic control friction plate type gear shifting mechanism can realize manual and automatic gear shifting, effectively ensure the use stability and reliability, and has compact structure and small volume.

Further, in the friction plate type two-gear speed reducer, a support is formed in the speed reducer casing, the support divides the speed reducer casing into a speed changing cavity and a gear shifting cavity, a mounting hole is formed in the center of the support, the input shaft penetrates through the speed changing cavity and the gear shifting cavity through the mounting hole, the first-gear driving gear and the second-gear driving gear are arranged in the speed changing cavity, and the gear shifting mechanism is arranged in the gear shifting cavity; two keep off the driving gear and be connected with the support rotation through bearing two, the periphery of the spline hub one of the casing left end of shifting is connected with the support rotation through bearing three, and the center of support is sunken right and is formed the recess that is used for holding the bearing, and the mounting hole is located the center of recess, bearing two sets up in the recess, bearing three sets up in the mounting hole.

Further, in the friction plate type two-gear speed reducer, the second-gear driving gear includes a gear hub portion and a sleeve portion, the sleeve portion is in a stepped cylinder shape, the gear hub portion is formed in a first step section of a left end portion of the sleeve portion, the spline hub portion is formed in a third step section of a right end portion of the sleeve portion, the bearing sleeve is arranged outside the second step section of the sleeve portion, and the bearing first is arranged in the first step section of the sleeve portion; and a fourth bearing is arranged between the second gear driving gear and the input shaft and is arranged in the second stepped section of the sleeve part.

Further, in the friction plate type two-gear speed reducer, a right end cover is arranged at the right end of the speed reducer shell, a bearing seat is formed by the inner side of the right end cover in a protruding mode, the right end portion of the input shaft is rotatably supported in the bearing seat through a fifth bearing, a bearing mounting hole is formed by the right end portion of the gear shifting shell in an extending mode, and a sixth bearing is arranged in the bearing mounting hole and is rotatably connected to the periphery of the bearing seat through the sixth bearing; an annular electromagnet support is further formed in the inner side of the right end cover of the speed reducer shell in a protruding mode, the electromagnet support is located on the radial outer side of the bearing seat, and the electromagnet is fixed in the electromagnet support.

The utility model has the advantages that:

1. the two-gear speed reducer can provide two sets of speed reduction ratios, expand the efficient interval of the motor, consider both the dynamic property and the economical efficiency of the electric vehicle, reduce the energy consumption of the motor, prolong the service life and reduce the noise, vibration and part loss during high-speed running;

2. the overrunning type gear shifting is realized by utilizing the one-way clutch, the problem of power interruption cannot occur in the gear shifting process, and meanwhile, the wet friction plate gear shifting mechanism is adopted, so that the gear shifting impact is small, the pause and the frustration are avoided, the noise is low, and the service life is long;

3. the gear shifting device has the advantages of reasonable and compact structure, small volume, capability of realizing manual and automatic gear shifting, and effective guarantee of use stability and reliability.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

Fig. 2 is an enlarged view of fig. 1 at P.

In the figure: 1. a reducer housing; 1a, a speed change cavity; 1b, a gear shifting cavity; 11. a support; 12. a right end cap; 13. an electromagnet support; 14. a bearing seat; 15. a fifth bearing; 2. an input shaft; 21. a first gear driving gear; 22. a second gear driving gear; 23. a first bearing; 24. a second spline hub; 25. a second bearing; 26. a bearing IV; 27. a tooth hub portion; 28. a sleeve portion; 281. a first step section; 282. a second step section; 283. a third step section; 3. an intermediate shaft; 31. a first-gear driven gear; 32. a second driven gear; 4. a one-way clutch; 5. a gear shift mechanism; 50. a sixth bearing; 51. a gear shifting friction pair; 52. a shift housing; 53. a first spline hub; 54. a leading friction pair; 55. a first cam plate; 56. a second cam plate; 57. a ball bearing; 58. an electromagnet; 59. and a third bearing.

Detailed Description

The invention will now be further described with reference to the accompanying drawings and examples:

in the description of the present invention, it should be understood that the directions or positional relationships indicated by the terms "left", "right", "inside", "outside", and the like are the directions or positional relationships shown in the drawings, and are only for convenience of description of the present invention, and do not indicate or imply that the device or element referred to must have a specific direction, and therefore, should not be construed as limiting the present invention.

As shown in fig. 1, the present embodiment provides a friction plate type two-speed reducer, which includes a reducer case 1, an input shaft assembly, an intermediate shaft assembly, a gear shift mechanism 5, and an output shaft (not shown).

The input shaft assembly comprises an input shaft 2 which is rotatably supported in the reducer shell 1, a first gear driving gear 21 and a second gear driving gear 22 which are arranged on the input shaft 2, and the input shaft 2 is connected with a driving motor of the whole vehicle. A bracket 11 is formed in the reducer case 1, the bracket 11 divides the reducer case 1 into a speed changing chamber 1a and a gear shifting chamber 1b, and a mounting hole is formed in the center of the bracket 11. The input shaft 2 penetrates through the speed changing cavity 1a and the gear shifting cavity 1b through a mounting hole of the bracket 11, and the first-gear driving gear 21 and the second-gear driving gear 22 are arranged in the speed changing cavity 1 a. The jackshaft subassembly holds jackshaft 3 and a fender driven gear 31 of fixed connection on jackshaft 3 in locating reducer casing 1 including rotating, two keep off driven gear 32, jackshaft 3, one keeps off driven gear 31, two keep off driven gear 32 and all set up in speed changing chamber 1a, jackshaft 3 and input shaft 2 parallel arrangement, one keeps off driven gear 31 and keeps off driving gear 21 meshing transmission, two keep off driven gear 32 and two keep off driving gear 22 meshing transmission, the jackshaft subassembly passes through reduction gears and is connected with output shaft transmission. The shift mechanism 5 is provided in the right section of the input shaft 2, inside the shift chamber 1 b.

In order to realize the gear shifting function, the first-gear driving gear 21 is installed on the input shaft 2 through the one-way clutch 4, the inner ring of the one-way clutch 4 is fixedly connected with the input shaft 2, the outer ring of the one-way clutch 4 is fixedly connected with the first-gear driving gear 21, the one-way clutch 4 is set to allow the first-gear driving gear 21 to rotate in the positive direction relative to the input shaft 2, otherwise, the first-gear driving gear is locked, and the second-gear driving gear 22 is freely sleeved on the input shaft 2 through the first bearing 23. The gear shifting mechanism 5 comprises a gear shifting friction pair 51 and a gear shifting thrust structure, the gear shifting friction pair 51 comprises a plurality of driving gear shifting friction plates and driven gear shifting friction plates which are arranged at intervals and coaxial with the input shaft 2, the driving gear shifting friction plates are connected with the input shaft 2, the driven gear shifting friction plates are at least indirectly connected with the two gear driving gears 22, and the gear shifting thrust structure acts to press the driving gear shifting friction plates and the driven gear shifting friction plates of the gear shifting friction pair 51 so as to lock the two gear driving gears 22 and the input shaft 2 to realize gear shifting.

The principle of vehicle gear shifting is as follows: when a vehicle is in a first gear, a second-gear driving gear 22 is sleeved on an input shaft 2 in an empty mode, a driving motor drives the input shaft 2 to rotate in a forward direction, a first-gear driving gear 21 has a reverse rotation trend relative to the input shaft 2, the first-gear driving gear 21 is locked with the input shaft 2 under the action of a one-way clutch 4 and rotates in the forward direction along with the input shaft 2, the first-gear driving gear 21 drives the second-gear driving gear 22 to idle on the input shaft 2 through an intermediate shaft assembly, and meanwhile, the first-gear driving gear 21 drives an output shaft to rotate through the intermediate shaft assembly and a speed reduction mechanism, so that the vehicle advances at a low speed; when hanging two grades, the thrust structure action of shifting compresses tightly the owner of the friction pair 51 of shifting, driven friction disc of shifting, cause two fender driving gears 22 and 2 locking synchronous forward rotations of input shaft, two fender driving gears 22 pass through two fender driven gear 32, jackshaft 3, one keeps off driven gear 31 and drives one fender driving gear 21 forward rotations, process the second grade and accelerate, consequently one keeps off driving gear 21 rotational speed and is higher than input shaft 2 far away, one-way clutch 4 surmounts the unblock, one keeps off driving gear 21 relative input shaft 2 forward idle running, two keep off driving gear 22 simultaneously via jackshaft subassembly, reduction gears drives the output shaft rotation, the vehicle advances at a high speed.

As shown in fig. 1 and 2, the connection structure between the driven shift friction plate and the second gear driving gear 22 specifically includes: the shift mechanism 5 further comprises a shift housing 52, the shift housing 52 is arranged coaxially with the input shaft 2, a shift friction pair 51 is arranged in the shift housing 52 and abuts against the inner side of the left end portion of the shift housing 52, and a driven shift friction plate of the shift friction pair 51 is connected with the shift housing 52. The left end of the gear shifting housing 52 extends axially to form a first spline hub 53 with an internal spline, the right end of the second gear driving gear 22 is formed with a second spline hub 24 with an external spline, and the gear shifting housing 52 and the second gear driving gear 22 are in meshed connection through the first spline hub 53 and the second spline hub 24, so that the driven gear shifting friction plates are indirectly connected with the second gear driving gear 22 through the gear shifting housing 52.

The shift thrust arrangement described above includes a shift actuator, leading friction pair 54 and leading actuating assembly, which are in turn located to the right of shift friction pair 51. The gear shift actuator is a relative rotation actuator, in this embodiment a ball ramp type actuator, comprising a first cam plate 55, a second cam plate 56 and a plurality of rolling elements, in this embodiment balls 57, circumferentially arranged therebetween. The first cam plate 55 is adjacent to the shifting friction pair 51, is circumferentially and fixedly sleeved on the input shaft 2 through spline connection and rotates synchronously with the input shaft 2, and the second cam plate 56 is provided with an external spline which is axially and fixedly sleeved on the input shaft 2. The opposite end surfaces of the first cam disc 55 and the second cam disc 56 are respectively provided with a plurality of circular arc-shaped track grooves distributed along the circumference, the depth of each track groove changes along the circumferential direction, each ball 57 is clamped between one track groove of the first cam disc 55 and one track groove of the second cam disc 56, under the condition of no influence of other external force, the balls 57 are clamped at the deepest parts of the two track grooves, the first cam disc 55 drives the second cam disc 56 to synchronously rotate through the balls 57, and the two cam discs rotate relatively to enable the balls 57 to roll in the track grooves to enable the first cam disc 55 to generate axial displacement. It is within the scope of the present invention to replace the ball ramp actuator with other types of relative rotation actuators herein. The front guide friction pair 54 is sleeved between the second cam disc 56 and the shift housing 52 and comprises a plurality of driving front guide friction plates and driven front guide friction plates which are arranged at intervals, external teeth of the driving front guide friction plates are meshed with internal teeth arranged in the shift housing 52 to realize connection, and internal teeth of the driven front guide friction plates are meshed with external splines of the second cam disc 56 to realize connection. The pilot actuating assembly is used to drive the leading and trailing friction plates of the leading friction pair 54 into compression with one another, thereby connecting the second cam plate 56 of the shift actuator with the shift housing 52 for rotation relative to the first cam plate 55, causing the first cam plate 55 to move axially leftward to compress the leading and trailing drive friction plates of the shift friction pair 51.

The front guiding actuating component is an electromagnetic actuating mechanism and comprises an electromagnet 58 arranged outside the right end face of the gear shifting shell 52, the electromagnet 58 is fixed with the speed reducer shell 1, specifically, the right end of the speed reducer shell 1 is provided with a right end cover 12, the inner side of the right end cover 12 protrudes to form an annular electromagnet support 13, the electromagnet 58 is fixed in the electromagnet support 13, a conducting wire extends into the speed reducer shell 1 and is electrically connected with the electromagnet 58, and the electrification of the electromagnet 58 can cause the main and driven front guiding friction plates of the front guiding friction pair 54 to be mutually pressed.

The working principle of the gear shifting thrust structure is as follows: when the second gear is shifted, the electromagnet 58 is electrified to attract the driving and driven front friction plates of the front friction pair 54 to press against each other, so that the second cam plate 56 of the shift actuator is connected with the shift housing 52 and rotates relative to the first cam plate 55, the ball 57 is forced to move along the track groove to the shallow position to press the first cam plate 55, the first cam plate 55 axially moves leftwards to press the driving and driven shift friction plates of the shift friction pair 51, and the second gear driving gear 22 is locked with the input shaft 2 to realize the gear shifting.

The specific mounting structure of the second gear driving gear 22, the shift housing 52, and the input shaft 2 is as follows:

the second gear pinion 22 includes a gear hub portion 27 and a sleeve portion 28, the sleeve portion 28 has a stepped cylindrical shape, the gear hub portion 27 is formed in a first step 281 of a left end portion of the sleeve portion 28, the second spline hub portion 24 is formed in a third step 283 of a right end portion of the sleeve portion 28, and a second bearing 25 is sleeved on the second step 282 of the sleeve portion 28. A first bearing 23 is disposed in the first step 281 of the casing portion 28, and a second bearing 26, two bearings 26 in this embodiment, is disposed between the second gear pinion 22 and the input shaft 2 and side by side in the second step 282 of the casing portion 28. The second gear driving gear 22 is freely sleeved on the input shaft 2 through a first bearing 23 and a fourth bearing 26, and is rotatably connected with the bracket 11 of the speed reducer casing 1 through a second bearing 25. The center of the bracket 11 is recessed rightwards to form a groove for accommodating the bearing, the mounting hole of the bracket 11 is positioned at the center of the groove, and the second bearing 25 is arranged in the groove.

The outer periphery of the first spline hub 53 at the left end of the shift housing 52 is sleeved with a third bearing 59, the third bearing 59 is arranged in the mounting hole of the bracket 11, and the left end of the shift housing 52 is rotatably connected with the bracket 11 through the third bearing 59. The bearing seat 14 is formed by protruding the inner side of the right end cover 12 of the reducer casing 1, the bearing seat 14 is located on the radial inner side of the electromagnet support 13, the right end portion of the gear shifting casing 52 extends to form a bearing mounting hole, a bearing six 50 is arranged in the bearing mounting hole, and the right end of the gear shifting casing 52 is rotatably connected to the periphery of the bearing seat 14 through the bearing six 50. A bearing five 15 is arranged in the bearing seat 14, the right end part of the input shaft 2 is rotatably supported at the right end of the reducer casing 1 through the bearing five 15, and the left end of the input shaft 2 is connected with the driving motor and is rotatably connected with the left end of the reducer casing 1.

Finally, it is understood that various other changes and modifications can be made by those skilled in the art based on the technical idea of the present invention, and all such changes and modifications should fall within the scope of the claims of the present invention.

Claims

1. The utility model provides a friction plate formula two keep off reduction gear, includes retarder housing, input shaft subassembly, intermediate shaft subassembly, gearshift and output shaft, the input shaft subassembly holds the input shaft of locating in the retarder housing and locates one on the input shaft and keep off driving gear, two fender driving gears including rotating, the input shaft is connected with the driving motor of whole car, the intermediate shaft subassembly includes keeps off driven gear, two fender driven gear with the parallel jackshaft of input shaft and fixed connection are epaxial in the jackshaft, one keep off driven gear with one keeps off driving gear meshing transmission, two keep off driven gear with two fender driving gear meshing transmission, the intermediate shaft subassembly passes through reduction gears and is connected its characterized in that with output shaft transmission:

the first-gear driving gear is arranged on the input shaft through a one-way clutch, an inner ring of the one-way clutch is fixedly connected with the input shaft, an outer ring of the one-way clutch is fixedly connected with the first-gear driving gear, the one-way clutch is set to allow the first-gear driving gear to rotate in the positive direction relative to the input shaft, otherwise, the one-way clutch is locked, and the second-gear driving gear is sleeved on the input shaft through a bearing I in an empty mode;

the gear shifting mechanism is arranged at the right section of the input shaft and comprises a gear shifting friction pair and a gear shifting thrust structure, the gear shifting friction pair comprises a plurality of driving gear shifting friction plates and driven gear shifting friction plates which are arranged at intervals and are coaxial with the input shaft, the driving gear shifting friction plates are connected with the input shaft, the driven gear shifting friction plates are at least indirectly connected with the two-gear driving gear, and the gear shifting thrust structure can compress the driving gear and the driven gear shifting friction plates of the gear shifting friction pair to lock the two-gear driving gear and the input shaft to realize gear shifting.

2. The friction plate type two-gear speed reducer according to claim 1, wherein: the gear shifting mechanism further comprises a gear shifting shell, the gear shifting shell and the input shaft are coaxially arranged, the gear shifting friction pair is arranged in the gear shifting shell and attached to the inner side of the left end part of the gear shifting shell, and a driven gear shifting friction plate of the gear shifting friction pair is connected with the gear shifting shell; the left end axial extension of the casing of shifting forms the spline hub one that has the internal spline, and the right-hand member of keeping off the driving gear is formed with the spline hub two that has the external spline, and the casing of shifting passes through spline hub one, the meshing of spline hub two with two fender driving gears to be connected, causes driven gear shift friction disc to link together through the casing of shifting with keeping off the indirect of driving gear.

3. The friction plate type two-speed reducer according to claim 2, wherein: the gear shifting thrust structure comprises a gear shifting actuator, a front guide friction pair and a front guide actuating component which are arranged on the right side of the gear shifting friction pair in sequence;

the gear shifting actuator is a relative rotation actuator and comprises a first cam disc, a second cam disc and a plurality of rolling parts which are circumferentially arranged between the first cam disc and the second cam disc, the first cam disc is circumferentially and fixedly sleeved on the input shaft through spline connection and is adjacent to the gear shifting friction pair, the second cam disc is provided with an external spline, and the second cam disc is axially and fixedly sleeved on the input shaft; the opposite end surfaces of the first cam disc and the second cam disc are respectively provided with a plurality of circular arc-shaped track grooves distributed along the circumference, the depth of each track groove changes along the circumferential direction, each rolling part is clamped between one track groove of the first cam disc and one track groove of the second cam disc, and the two cam discs rotate relatively to each other so that the rolling parts roll in the track grooves to cause the first cam discs to generate axial displacement;

the front guide friction pair is sleeved between the second cam disc and the gear shifting shell and comprises a plurality of driving front guide friction plates and driven front guide friction plates which are arranged at intervals, the driving front guide friction plates are connected with the gear shifting shell, and the driven front guide friction plates are connected with the second cam disc;

the pilot actuating assembly is used for driving the driving pilot friction plate and the driven pilot friction plate of the pilot friction pair to press against each other, so that the second cam plate of the gear shifting actuator is connected with the gear shifting shell and rotates relative to the first cam plate, and the first cam plate moves axially to press the driving shift friction plate and the driven shift friction plate of the gear shifting friction pair.

4. The friction plate type two-gear speed reducer according to claim 3, wherein: the front guiding actuating assembly comprises an electromagnet arranged outside the right end face of the gear shifting shell, the electromagnet is fixed with the reducer shell, and the electromagnet is electrified to enable a driving front guiding friction plate and a driven front guiding friction plate of the front guiding friction pair to be mutually pressed.

5. The friction plate type two-speed reducer according to claim 2, wherein: a bracket is formed in the speed reducer shell, the speed reducer shell is divided into a speed changing cavity and a gear shifting cavity by the bracket, a mounting hole is formed in the center of the bracket, an input shaft penetrates through the mounting hole and penetrates through the speed changing cavity and the gear shifting cavity, a first-gear driving gear and a second-gear driving gear are arranged in the speed changing cavity, and a gear shifting mechanism is arranged in the gear shifting cavity; two keep off the driving gear and be connected with the support rotation through bearing two, the periphery of the spline hub one of the casing left end of shifting is connected with the support rotation through bearing three, and the center of support is sunken right and is formed the recess that is used for holding the bearing, and the mounting hole is located the center of recess, bearing two sets up in the recess, bearing three sets up in the mounting hole.

6. The friction plate type two-speed reducer according to claim 5, wherein: the second-gear driving gear comprises a gear hub portion and a sleeve portion, the sleeve portion is in a stepped cylinder shape, the gear hub portion is formed in a first step section of the left end portion of the sleeve portion, a spline hub portion is formed in a third step section of the right end portion of the sleeve portion, a bearing sleeve is arranged outside the second step section of the sleeve portion in a sleeved mode, and a bearing I is arranged in the first step section of the sleeve portion; and a fourth bearing is arranged between the second gear driving gear and the input shaft and is arranged in the second stepped section of the sleeve part.

7. The friction plate type two-speed reducer according to claim 4, wherein: the right end of the speed reducer shell is provided with a right end cover, the inner side of the right end cover is protruded to form a bearing seat, the right end part of the input shaft is rotatably supported in the bearing seat through a bearing five, the right end part of the gear shifting shell extends to form a bearing mounting hole, and a bearing six is arranged in the bearing mounting hole and is rotatably connected to the periphery of the bearing seat through the bearing six; an annular electromagnet support is further formed in the inner side of the right end cover of the speed reducer shell in a protruding mode, the electromagnet support is located on the outer side of the bearing seat in the radial direction, and the electromagnet is fixed in the electromagnet support.