Novel synchronizer and synchronizing method suitable for electric drive axle and electric automobile

Abstract

The invention discloses a novel synchronizer suitable for an electric drive axle and an electric automobile and a synchronizing method, and relates to the technical field of automobile transmission, the novel synchronizer comprises a joint sleeve, the inner side of the joint sleeve is coaxially meshed with a splined hub, the outer edge of the splined hub is concaved inwards in the radial direction to form a mounting cavity, and a mounting seat is arranged in the mounting cavity and connected with the joint sleeve; the pre-synchronization assembly is arranged in the mounting base. In the electronic synchronization process, zero rotating speed difference and zero rotating angle difference between the joint sleeve and the gear position gear do not need to be achieved any more, and when the preset rotating speed difference is achieved between the joint sleeve and the gear position gear, synchronization operation can be started. And meanwhile, the rotating speed of the joint sleeve is adjusted, and the joint sleeve moves towards the joint gear and is in butt joint, so that the synchronization time is shortened. When the joint sleeve is connected with the combination gear to generate axial and angular impact, the impact can be counteracted through the spring, so that the gear shifting impact is greatly reduced, and the gear shifting quality of the AMT of the electric drive axle is improved.

Description

Technical Field

[0001] The invention relates to the technical field of automobile transmission, and in particular to a novel synchronizer and a synchronization method suitable for an electric drive axle and an electric vehicle. Background Art

[0002] The motors in electric vehicles and electric drive axles have excellent low-speed control capabilities and precise working mode switching capabilities. In order to simplify the structure, reduce manufacturing costs and improve integration, electric vehicles and electric drive axles are currently developing towards clutchless AMT (automatic mechanical transmission). The shift quality of clutchless AMT transmission is mainly reflected in the shift time and shift impact. Due to the defect of power interruption when AMT shifts, the shift time should be shortened as much as possible. However, shortening the shift time will bring greater shift impact. Therefore, while shortening the shift time, reducing the shift impact is the key to improving the shift quality of electric drive axle AMT.

[0003] Studies have shown that the speed synchronization phase accounts for nearly 50% of the entire shift time. Shortening the speed synchronization phase can significantly shorten the shift time.

[0004] The method of combining mechanical synchronization and electronic synchronization is the best speed synchronization method at present. The relative speed is actively controlled by the motor, while the synchronizer components inside the transmission are retained. Generally, the motor is used to control the pre-synchronization, so that the clutch and the gear gear reach "zero speed difference" and "zero angle difference", and then mechanical synchronization is used to achieve precise synchronization. It has the following defects: ① The mechanical synchronization part directly uses the traditional synchronizer, which has a complex structure. In addition, the current electric vehicles have eliminated the clutch, resulting in large inertia and severe wear of the mechanical synchronizer.

[0005] ② The electronic synchronization part needs to meet the requirements of "zero speed difference" and "zero angle difference", which makes the electronic synchronization control algorithm complex and the precise synchronization control difficult, which in turn causes the shifting time to be prolonged.

[0006] In view of this, how to provide a synchronizer and a synchronization method that can shorten the time of the speed synchronization stage and reduce the gear shifting shock is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0007] The purpose of the present invention is to provide a new synchronizer and synchronization method suitable for electric drive axles and electric vehicles to solve the problems existing in the prior art.

[0008] To achieve the above object, the present invention provides a novel synchronizer suitable for an electric drive axle and an electric vehicle, comprising: The inner side of the engagement sleeve is coaxially meshed with the spline hub, and the outer edge of the spline hub is radially concave to form a mounting chamber; the engagement sleeve is drivingly connected to the shift motor; A gear is provided on one side of the corresponding engagement sleeve, the engagement sleeve can move axially and mesh with the engagement gear, the gear is connected to the drive motor by transmission; the spline hub is connected to the transmission shaft by splines, and a bearing is provided between the transmission shaft and the gear; A mounting seat, disposed in the mounting chamber and connected to the engagement sleeve; A pre-synchronization component is arranged in the mounting seat, with its connecting end facing the engaging gear, and a convex tooth groove is provided on the side of the engaging gear corresponding to the connecting end; when the speed difference between the engaging sleeve and the engaging gear reaches a preset speed difference, the shifting motor drives the engaging sleeve to approach the engaging gear axially, and the convex tooth groove rotates to a position corresponding to the connecting end, and the connecting end is stuck in the convex tooth groove.

[0009] Further, the pre-synchronization component includes: A pre-synchronization column, the front end of which is a connection end, and the rear end is connected to a spring washer through a spring; A cavity matching the shape of the pre-synchronization column is defined in the mounting seat, the pre-synchronization column, the spring and the spring gasket are all located in the cavity, the spring gasket is fixedly connected to the mounting seat, and the front end of the pre-synchronization column extends out from the cavity.

[0010] Furthermore, a clamping portion is provided at the front end of the pre-synchronization column, and the engaging gear is radially concave to form the convex tooth groove. When the engaging sleeve approaches the engaging gear axially, the convex tooth groove rotates to a position corresponding to the clamping portion, and the clamping portion is engaged with the wall surface of the convex tooth groove.

[0011] Furthermore, the angular width of the convex tooth groove is greater than the angular width of the clamping portion.

[0012] Furthermore, the gear gear includes a high gear gear and a low gear gear, the engagement sleeve is located between the high gear gear and the low gear gear, the engaging portion corresponding to the high gear gear tilts in a counterclockwise direction, and the engaging portion corresponding to the low gear gear tilts in a clockwise direction.

[0013] The present invention also provides a synchronization method applicable to an electric drive axle and an electric vehicle, and the method uses the novel synchronizer applicable to the electric drive axle and the electric vehicle, comprising the following steps: S1: The engagement sleeve is in the neutral position, the drive motor adjusts the speed of the engagement gear toward the target speed, and the shift motor drives the engagement sleeve to move toward the engagement gear; S2: The drive motor starts to release torque and does not actively output torque; when the speed difference between the engagement sleeve and the engagement gear reaches the preset speed difference, the engagement sleeve approaches the engagement gear, the clamping portion of the pre-synchronization column is clamped into the convex tooth groove and engages with the wall surface of the convex tooth groove, and the drive motor starts to output torque; S3: The driving motor continues to maintain the state of not actively outputting torque; the shifting motor drives the coupling sleeve to continue to move toward the engaging gear, and the spring is compressed; the outer gear ring of the engaging gear meshes with the coupling sleeve, and synchronization ends.

[0014] Further, in step S1: the target speed of the clutch is ;

[0015] in, is the resistance torque of the vehicle moving forward, is the equivalent moment of inertia of the output end of the electric drive axle.

[0016] Further, in step S2, the preset speed difference is ;

[0017] in, To drive the motor power output to the intermediate transmission ratio of the engaging gear, is the equivalent moment of inertia of the electric drive axle input, The output torque of the driving motor is is the resistance torque of the vehicle moving forward, is the equivalent moment of inertia of the output end of the electric drive axle. The torque generated for pre-synchronizing the pre-synchronizing column with the engaging gear.

[0018] Further, in step S2, when the engaging sleeve is connected to the engaging gear and the convex tooth groove corresponds to the clamping portion, the clamping portion is clamped into the convex tooth groove.

[0019] Further, in step S2, when the engaging sleeve is connected to the engaging gear and the convex tooth groove does not correspond to the clamping portion, the clamping portion is connected to the side of the engaging gear; the engaging gear and the engaging sleeve rotate relative to each other, and when the convex tooth groove rotates to correspond to the clamping portion, the clamping portion is clamped into the convex tooth groove.

[0020] The present invention discloses the following technical effects: 1. A pre-synchronization component is embedded in the coupling sleeve. During the electronic synchronization process, it is no longer necessary to achieve "zero speed difference" and "zero angle difference" between the coupling sleeve and the gear. When the preset speed difference is reached between the coupling sleeve and the gear, the synchronization operation can begin.

[0021] 2. The present invention adopts a method of simultaneously performing mechanical synchronization and electronic synchronization, that is, simultaneously performing speed adjustment of the engagement sleeve and movement and docking of the engagement sleeve toward the engagement gear, thereby shortening the synchronization time.

[0022] 3. To address the gear shift shock, the present invention adopts a pre-synchronization component consisting of a pre-synchronization column, a spring and a spring gasket. When the coupling sleeve is connected with the engaging gear to generate axial and angular shocks, the shocks can be offset by the spring, thereby greatly reducing the gear shift shock and improving the gear shift quality of the electric drive axle AMT.

[0023] 4. Compared with the existing mechanical synchronization based on the friction principle, the present application adopts a synchronization structure and a synchronization method in which the pre-synchronization column clamping part is clamped with the engaging gear, which improves the power transmission efficiency and reduces the heat generation of the electric drive axle. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 It is a schematic diagram of the coordination of the high gear, the engaging gear and the pre-synchronization assembly (after synchronization); Figure 3 It is a schematic diagram of the cooperation between the pre-synchronization component, the spline hub and the coupling sleeve (after synchronization); Figure 4 It is a schematic diagram of the cooperation between the mounting seat and the pre-synchronization component; Figure 5 It is a schematic diagram of the pre-synchronization component; Figure 6 It is a schematic diagram of the installation of two sets of pre-synchronization components corresponding to the high gear and the low gear respectively; Figure 7 It is an assembly cross-sectional view of the engagement gear and the engagement sleeve; Figure 8 It is a schematic diagram of the pre-synchronization column being inserted into the convex tooth groove; Fig. 9 It is a cross-sectional view of the structure after the engagement sleeve and the engagement gear are synchronized; Fig.10 It is a schematic diagram of the pre-synchronization column and the engaging gear being connected when the pre-synchronization column and the convex tooth groove do not correspond to each other; Fig.11 It is a structural schematic diagram when the convex tooth groove rotates relatively to correspond to the pre-synchronization column; Among them, 1. coupling sleeve; 2. spline hub; 3. high gear; 4. low gear; 5. coupling gear; 501. convex tooth groove; 6. mounting seat; 7. pre-synchronization column; 701. clamping part; 8. spring; 9. spring gasket; 10. transmission shaft. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] The embodiment of the present invention provides a novel synchronizer suitable for an electric drive axle and an electric vehicle, comprising: The outer side of the engagement sleeve 1 cooperates with the shifting operation structure, and the inner side is coaxially meshed with the spline hub 2. The outer edge of the spline hub 2 is radially concave to form a mounting chamber, and there are three mounting chambers that are evenly spaced. The engagement sleeve 1 is transmission-connected to the shifting motor, and the shifting motor is used to drive the engagement sleeve 1 to move toward the engagement gear 5. The gear is provided with an engaging gear 5 on one side of the corresponding engaging sleeve 1. The engaging sleeve 1 can move axially and mesh with the engaging gear 5 to achieve the gear-engaging function. The gear is connected to the driving motor, and the driving motor can drive the gear to rotate. The spline hub 2 is connected to the transmission shaft 10 through the spline. Its function is to output the power transmitted by the coupling gear to the transmission shaft 10 through the spline, and also provide support for the entire synchronizer. A bearing is provided between the transmission shaft 10 and the gear. A mounting seat 6, disposed in the mounting chamber and connected to the coupling sleeve 1; The pre-synchronization component is arranged in the mounting seat 6, and its connecting end faces the engaging gear 5. A convex tooth groove 501 is provided on the side of the engaging gear 5 corresponding to the connecting end. When the speed difference between the engaging sleeve 1 and the engaging gear 5 reaches the preset speed difference, the shifting motor drives the engaging sleeve 1 axially close to the engaging gear 5, and the convex tooth groove 501 rotates to a position corresponding to the connecting end, and the connecting end is inserted into the convex tooth groove 501.

[0029] In this embodiment, the pre-synchronization component includes: The front end of the pre-synchronization column 7 is a connection end, and the rear end is connected to the spring gasket 9 through a spring 8; the spring 8 adopts a high-strength compression spring 8, and is connected to the pre-synchronization column 7 through a certain tension; A cavity matching the shape of the pre-synchronization column 7 is defined in the mounting seat 6. The pre-synchronization column 7, the spring 8 and the spring gasket 9 are all located in the cavity. The spring gasket 9 is fixedly connected to the mounting seat 6, which helps the spring 8 to evenly distribute pressure, avoids failure or wear of the spring 8 due to uneven pressure, and can also reduce the friction between the spring 8 and the engaging gear 5 or other components, thereby extending the service life of the synchronizer. The front end of the pre-synchronization column 7 extends from the cavity to the outside, ensuring that the front end of the pre-synchronization column 7 can preferentially connect with the engaging gear 5 during the gear shifting process. The cavity of the mounting seat 6 matches the shape of the pre-synchronization column 7, and can play a guiding role in the movement of the pre-synchronization column 7, ensuring a smooth synchronization process. In this embodiment, a clamping portion 701 is provided at the front end of the pre-synchronization column 7, and the engaging gear 5 is concave inwardly in the radial direction to form a convex tooth groove 501. When the engaging sleeve 1 approaches the engaging gear 5 in the axial direction, the convex tooth groove 501 rotates to a position corresponding to the clamping portion 701, and the clamping portion 701 is clamped with the wall surface of the convex tooth groove 501.

[0030] In this embodiment, the angular width of the convex tooth groove 501 is greater than the angular width of the clamping portion 701, which can reduce the gear impact in the pre-synchronization stage and increase the pre-synchronization speed.

[0031] In this embodiment, the gears include a high gear 3 and a low gear 4, the coupling sleeve 1 is located between the high gear 3 and the low gear 4, the clamping portion 701 corresponding to the high gear 3 is tilted in the counterclockwise direction, and the clamping portion 701 corresponding to the low gear 4 is tilted in the clockwise direction.

[0032] In this embodiment, two sets of pre-synchronization components are respectively arranged in the coupling sleeve 1 corresponding to the high-gear gear 3 and the low-gear gear 4 , and the two sets of pre-synchronization components are symmetrically arranged in the cavity of the same mounting seat 6 .

[0033] The present invention also provides a synchronization method applicable to an electric drive axle and an electric vehicle, using a new type of synchronizer applicable to the electric drive axle and the electric vehicle, comprising the following steps: S1: the drive motor stops outputting torque, and the sensor determines that the output torque of the drive motor is zero, the engagement sleeve 1 is in the neutral position, the drive motor adjusts the speed of the engagement gear 5 to the target speed, and the shift motor drives the engagement sleeve 1 to move toward the engagement gear 5; S2: the driving motor starts to release the torque and does not actively output the torque; when the speed difference between the engagement sleeve 1 and the engagement gear 5 reaches the preset speed difference, the engagement sleeve 1 approaches the engagement gear 5, the clamping portion 701 of the pre-synchronizing column 7 is clamped into the convex tooth groove 501 and is engaged with the wall surface of the convex tooth groove 501, and the driving motor starts to output the torque; S3: The driving motor continues to maintain the state of not actively outputting torque; the shifting motor drives the coupling sleeve 1 to continue to move toward the coupling gear 5, and the spring 8 is compressed; the outer gear ring of the coupling gear 5 meshes with the coupling sleeve 1, and the synchronization ends.

[0034] In step S1: the target speed of the clutch sleeve 1 is ;

[0035] in, is the resistance torque of the vehicle moving forward, is the equivalent moment of inertia of the output end of the electric drive axle.

[0036] In step S2, the preset speed difference is ;

[0037] in, To drive the motor power output to the intermediate transmission ratio of the engaging gear, is the equivalent moment of inertia of the electric drive axle input, The output torque of the driving motor is is the resistance torque of the vehicle moving forward, is the equivalent moment of inertia of the output end of the electric drive axle. The torque generated by the pre-synchronization of the pre-synchronization column and the engaging gear is determined by the shifting force applied to the engaging sleeve by the shifting motor, the position and size of the convex tooth groove on the engaging gear, and the inclination angle.

[0038] Compared with the high precision requirement of zero speed difference of electronic synchronization, the embodiment of the present invention allows the electronic synchronization stage to exist The speed difference is tested and found that the speed difference tolerance can reach about 25% by using this embodiment.

[0039] Mechanical synchronization is divided into two working conditions: ideal and non-ideal. In the ideal state, the engagement sleeve 1 is connected to the engagement gear 5 and the convex tooth groove 501 corresponds to the clamping portion 701. Figure 7 As shown, the clamping portion 701 is directly clamped into the convex tooth groove 501. Figure 8 As shown, after the synchronization is completed, Fig. 9 shown.

[0040] In a non-ideal state, the engagement sleeve 1 is connected to the engagement gear 5 and the convex tooth groove 501 does not correspond to the clamping portion 701. Fig.10 As shown, the clamping portion 701 is first connected to the side of the engagement gear 5; there is relative rotation between the engagement gear 5 and the engagement sleeve 1 (formed based on the speed difference), when the convex tooth groove 501 rotates to correspond to the clamping portion 701, the clamping portion 701 is clamped into the convex tooth groove 501 as shown in FIG. Fig.11 As shown, the following state changes are the same as Figure 7-Figure 9 .

[0041] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0042] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A new type of synchronizer suitable for electric drive axles and electric vehicles, characterized in that: include: An engagement sleeve (1) has an inner side coaxially meshed with a spline hub (2), and an outer edge of the spline hub (2) is radially concave to form a mounting chamber; the engagement sleeve (1) is drivingly connected to a gear shifting motor; A gear shift gear, an engaging gear (5) being arranged on one side corresponding to the engaging sleeve (1), the engaging sleeve (1) being movable in the axial direction and meshing with the engaging gear (5), the gear shift gear being transmission-connected to the driving motor; the spline hub (2) being connected to the transmission shaft (10) via a spline, a bearing being arranged between the transmission shaft (10) and the gear shift gear; A mounting seat (6) disposed in the mounting chamber and connected to the coupling sleeve (1); A pre-synchronization component is arranged in the mounting seat (6), with a connection end facing the engagement gear (5), and a convex tooth groove (501) is provided on a side surface of the engagement gear (5) corresponding to the connection end; when the speed difference between the engagement sleeve (1) and the engagement gear (5) reaches a preset speed difference, the shifting motor drives the engagement sleeve (1) to approach the engagement gear (5) in the axial direction, and the convex tooth groove (501) rotates to a position corresponding to the connection end, and the connection end is engaged in the convex tooth groove (501).

2. A novel synchronizer suitable for electric drive axles and electric vehicles according to claim 1, characterized in that: The pre-synchronization component comprises: A pre-synchronization column (7), the front end of which is a connection end, and the rear end of which is connected to a spring washer (9) via a spring (8); A cavity matching the shape of the pre-synchronization column (7) is defined in the mounting seat (6); the pre-synchronization column (7), the spring (8) and the spring gasket (9) are all located in the cavity; the spring gasket (9) is fixedly connected to the mounting seat (6); and the front end of the pre-synchronization column (7) extends outward from the cavity.

3. A new type of synchronizer suitable for electric drive axles and electric vehicles according to claim 2, characterized in that: The front end of the pre-synchronization column (7) is provided with a clamping portion (701), and the engaging gear (5) is radially concave to form the convex tooth groove (501); when the engaging sleeve (1) approaches the engaging gear (5) in the axial direction, the convex tooth groove (501) rotates to a position corresponding to the clamping portion (701), and the clamping portion (701) is clamped with the wall surface of the convex tooth groove (501).

4. A new type of synchronizer suitable for electric drive axles and electric vehicles according to claim 3, characterized in that: The angular width of the convex tooth groove (501) is greater than the angular width of the clamping portion (701).

5. A novel synchronizer suitable for electric drive axles and electric vehicles according to claim 4, characterized in that: The gears comprise a high gear (3) and a low gear (4); the engagement sleeve (1) is located between the high gear (3) and the low gear (4); the engaging portion (701) corresponding to the high gear (3) tilts in a counterclockwise direction, and the engaging portion (701) corresponding to the low gear (4) tilts in a clockwise direction.

6. A synchronization method applicable to an electric drive axle and an electric vehicle, characterized in that: A novel synchronizer applicable to an electric drive axle and an electric vehicle according to any one of claims 3 to 5 is applied, comprising the following steps: S1: the engagement sleeve (1) is in a neutral position, the drive motor adjusts the rotation speed of the engagement gear (5) toward the target rotation speed, and at the same time the shift motor drives the engagement sleeve (1) to move toward the engagement gear (5); S2: the driving motor starts to release torque and does not actively output torque; when the speed difference between the engagement sleeve (1) and the engagement gear (5) reaches a preset speed difference, the engagement sleeve (1) moves closer to the engagement gear (5), and the engaging portion (701) of the pre-synchronizing column (7) engages with the convex tooth groove (501) and the wall surface of the convex tooth groove (501); S3: the driving motor continues to maintain a state of not actively outputting torque; the shifting motor drives the coupling sleeve (1) to continue to move in the direction of the coupling gear (5), and the spring (8) is compressed; the outer gear ring of the coupling gear (5) meshes with the coupling sleeve (1), and synchronization ends.

7. A synchronization method applicable to an electric drive axle and an electric vehicle according to claim 6, characterized in that: In step S1: the target speed of the clutch sleeve (1) is ; in, is the resistance torque of the vehicle moving forward, is the equivalent moment of inertia of the output end of the electric drive axle.

8. A synchronization method applicable to an electric drive axle and an electric vehicle according to claim 6, characterized in that: In step S2, the preset speed difference is ; in, The intermediate transmission ratio for outputting the power of the driving motor to the engaging gear (5) is is the equivalent moment of inertia of the electric drive axle input, The output torque of the driving motor is is the resistance torque of the vehicle moving forward, is the equivalent moment of inertia of the output end of the electric drive axle, The torque generated by pre-synchronizing the pre-synchronizing column (7) with the engaging gear (5).

9. A synchronization method applicable to an electric drive axle and an electric vehicle according to claim 6, characterized in that: In step S2, when the engagement sleeve (1) is connected to the engagement gear (5) and the convex tooth groove (501) corresponds to the clamping portion (701), the clamping portion (701) is clamped into the convex tooth groove (501).

10. A synchronization method applicable to an electric drive axle and an electric vehicle according to claim 6, characterized in that: In step S2, when the engagement sleeve (1) is connected to the engagement gear (5) and the convex tooth groove (501) does not correspond to the clamping portion (701), the clamping portion (701) is connected to the side surface of the engagement gear (5); the engagement gear (5) and the engagement sleeve (1) rotate relative to each other, and when the convex tooth groove (501) rotates to correspond to the clamping portion (701), the clamping portion (701) is clamped into the convex tooth groove (501).

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