CN217197777U

CN217197777U - Electric gear shifting actuating mechanism and electric bridge driving system

Info

Publication number: CN217197777U
Application number: CN202220229649.0U
Authority: CN
Inventors: 蔚帅; 王海波
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2022-01-27
Filing date: 2022-01-27
Publication date: 2022-08-16
Anticipated expiration: 2032-01-27

Abstract

The application provides electronic actuating mechanism and electric bridge actuating system of shifting, electronic actuating mechanism of shifting includes: the motor (1) is provided with a motor shaft (11), and the output end of the motor shaft (11) is provided with a first external gear (12); a gear member (2) including a first internal gear (21) and a second external gear (22), the first external gear (12) meshing with the first internal gear (21) to form an internally meshing gear pair; and a transmission unit (3), wherein the second external gear (22) is meshed with the gear of the transmission unit (3) to transmit power to the transmission unit (3). Thus, the manufacturing cost of the electric shift actuator can be greatly reduced.

Description

Electric gear shifting actuating mechanism and electric bridge driving system

Technical Field

The present application relates to the field of electric bridge driving systems, and more particularly, to an electric shift actuator and an electric bridge driving system.

Background

An electric bridge (e-Axle) drive system is widely used in electric vehicles and the like. Fig. 1 shows a cross-sectional view of an electric shift actuator of a possible bridge drive system. As shown in fig. 1, the electric shift actuator includes a motor 91, a pinion 93 connected to a motor shaft 92 of the motor 91 via a spline or the like in a non-rotatable manner, a crown gear 94 meshing with the pinion 93, a screw 95 connected to the crown gear 94 in a non-rotatable manner, and a nut 96 converting a rotational motion of the screw 95 into a linear motion, wherein the screw 95 and the nut 96 together constitute a ball screw pair.

When the electric shift actuator is operated, the motor 91 rotates the motor shaft 92, transmits torque to the pinion 93, and then to the crown gear 94, the lead screw 95, and the nut 96, thereby linearly moving the nut 96. When the nut 96 is moved linearly, a shift fork, not shown, for example, connected to the nut 96 is moved, so that a shift actuating function is performed.

The motor in the electric gear shifting actuating mechanism is a special motor with small volume, which causes high production cost and poor competitiveness of the electric gear shifting actuating mechanism. It is desirable to be able to use mass-produced general-purpose motors instead of the above-described special-purpose motors.

SUMMERY OF THE UTILITY MODEL

Problem to be solved by utility model

It is an object of the present application to overcome or at least alleviate the above-mentioned deficiencies of the prior art and to provide an electric shift actuator and a bridge drive system using the same.

Means for solving the problems

The application provides an electronic actuating mechanism that shifts, includes: the motor is provided with a motor shaft, and the output end of the motor shaft is provided with a first external gear; a gear member including a first internal gear and a second external gear, the first external gear meshing with the first internal gear to form an internally meshing gear pair; and a transmission unit to which the second external gear is engaged with a gear of the transmission unit to transmit power.

In at least one aspect, the first external gear has a diameter or number of teeth smaller than that of the first internal gear, and the first external gear is inserted into the first internal gear eccentrically with respect to a central axis of the first internal gear.

In at least one embodiment, the first external gear is integrally formed with an output end of the motor shaft, the first internal gear is provided at one axial end of the gear member, the second external gear is provided at the other axial end of the gear member, and the first internal gear and the second external gear are arranged in a staggered manner in the axial direction of the gear member.

In at least one aspect, the electric shift actuator further includes a housing for at least partially housing the motor, the gear member, and the transmission unit, and a bearing is provided on an outer periphery of one end of the gear member in an axial direction, the bearing rotatably supporting the gear member within the housing.

In at least one aspect, the transmission unit includes a sliding screw transmission pair including a screw and a nut for converting a rotational motion of the screw into a linear motion.

In at least one technical scheme, the nut includes working of plastics and metalwork, the inner periphery of working of plastics be formed with the transmission external screw thread of screw rod carries out screw thread drive's transmission internal thread, the metalwork is located the periphery of working of plastics, the metalwork is equipped with the lug that is used for being connected with the shift fork of shifting.

In at least one technical scheme, the inner periphery of the metal piece is provided with a groove, the outer periphery of the plastic piece is provided with a protruding part, and the protruding part is embedded into the groove to prevent the metal piece and the plastic piece from moving axially relative to each other.

In at least one aspect, the plastic member and the metal member are formed as one body by insert molding.

In at least one aspect, an end of the metal piece is non-circular in shape.

The application also provides an electric bridge driving system, which comprises the electric gear shifting actuating mechanism in any one of the technical schemes.

Effect of the utility model

By adopting the technical scheme, the gear part with the first internal gear and the second external gear which is newly designed is adopted, so that the special motor can be replaced by the universal motor without greatly changing the overall structure of the electric gear shifting actuating mechanism. Thus, the manufacturing cost of the electric shift actuator can be greatly reduced.

Drawings

FIG. 1 shows a cross-sectional view of one possible electrical shift actuator.

Fig. 2 shows a cross-sectional view of an electric shift actuator according to an embodiment of the present application.

Fig. 3 shows a front view of a gear member of an electric shift actuator according to an embodiment of the present application.

Fig. 4 shows a cross-sectional view of a gear member of an electric shift actuator according to an embodiment of the present application.

Fig. 5A, 5B and 5C show a perspective view, a perspective cutaway view and a cross-sectional view, respectively, of a transmission unit of an electrical shift actuator according to an embodiment of the present application.

Fig. 6A, 6B, 6C and 6D show a perspective view, a perspective cutaway view, a cross-sectional view and a rear view, respectively, of a nut of a transmission unit of an electric shift actuator according to an embodiment of the present application, wherein fig. 6D is viewed from the right side in fig. 6C.

Description of the reference numerals

91 a motor; 92 motor shaft; 93 a pinion gear; 94 crown gears; 95 lead screw; 96 nuts; 1, a motor; 11 motor shaft; 12 a first external gear; 2, a gear piece; 21 a first internal gear; 22 a second external gear; 23, a boss; 24 grooves; 25, a snap ring; 26 bearings; 3 a transmission unit; 31 a crown gear; 32 ball bearings; 33 sliding screw transmission pair; 34 a screw rod; 341 external transmission thread; 35 a nut; 36 a plastic part; 361 driving the internal thread; 362 a projection; 37 a metal member; 371 lug; 372 grooves; 4, a shell.

Detailed Description

Exemplary embodiments of the present application are described below with reference to the accompanying drawings. It should be understood that the detailed description is intended only to teach one skilled in the art how to make and use the present application, and is not intended to be exhaustive or to limit the scope of the application.

In the following description, the direction X, which coincides with the axial direction of the motor 1 and the axial direction of the gear member 2 in the electric shift actuator, and the direction Y, which coincides with the axial direction of the screw 34, are used.

The application provides an electric bridge driving system, and this electric bridge driving system includes electric gear shifting actuating mechanism, and electric gear shifting actuating mechanism is used for carrying out the actuating function that shifts of vehicle, and this vehicle can be pure electric vehicles or hybrid vehicle.

As shown in fig. 2 to 6D, the present application provides an electric shift actuator, which includes a motor 1, a gear member 2, and a transmission unit 3. Furthermore, the electric shift actuator comprises a housing 4 for at least partially housing the electric motor 1, the gear member 2, the transmission unit 3. The outer dimensions of the housing 4 are the same as those of the conventional case, and the inner dimensions thereof are appropriately adjusted by the motor 1, the gear member 2, and the transmission unit 3.

The motor 1 of the present application employs a general-purpose motor produced in mass production instead of the special motor 91 in fig. 1. The motor 1 of the present application has a motor shaft 11, and an output end (a lower end in fig. 2, 3, 4) of the motor shaft 11 is provided with a first external gear 12. In the illustrated embodiment, a plurality of teeth are formed on the outer circumference of the output end of the motor shaft 11 as the first external gear 12, that is, the first external gear 12 is integrally formed with the output end of the motor shaft 11. However, the present invention is not limited to this, and the first external gear 12 may be fixed to the output end of the motor shaft 11 via splines or the like as an independent member. The first external gear 12 meshes with a first internal gear 21 of a gear member 2 described later, and transmits power of the motor 1 to the gear member 2.

Further, since the motor 1 of the present invention is a general-purpose motor that is mass-produced, mass-produced parts can be used for the static electricity prevention cap, screws for fixing the motor 1 to the housing 4, and the like, which are not shown, and this contributes to a reduction in the manufacturing cost of the electric shift actuator.

As one feature of the present application, the present application employs the first external gear 12 and the gear member 2 instead of the pinion gear 93 in fig. 1. Specifically, in order to use a general-purpose motor 1 produced in large quantities instead of the special-purpose motor 91 in fig. 1 while ensuring the same shift stroke/load as in the case of using a special-purpose motor, the present application designs a completely new gear member 2, as shown in fig. 2, 3 and 4.

The gear member 2 of the present application includes a first internal gear 21 and a second external gear 22. In the illustrated embodiment, the gear member 2 has a plurality of internal teeth formed on the inner periphery thereof as the first internal gear 21, and a plurality of external teeth formed on the outer periphery thereof as the second external gear 22. However, the present invention is not limited to this, and the gear member 2 may be configured by integrally connecting the first internal gear 21 and the second external gear 22, which are separate members.

Further, it is preferable that the first internal gear 21 is provided at one end (upper end in fig. 2, 3, and 4) of the gear member 2 in the axial direction (i.e., direction X), the second external gear 22 is provided at the other end (lower end in fig. 2, 3, and 4) of the gear member 2 in the axial direction (i.e., direction X), and the first internal gear 21 and the second external gear 22 are arranged to be shifted in the axial direction (i.e., direction X) of the gear member 2.

The first external gear 12 of the motor shaft 11 meshes with the first internal gear 21 of the gear member 2 to form an internally meshing gear pair. Specifically, the output end of the motor shaft 11 is inserted into the gear member 2, and the first external gear 12 is engaged with the first internal gear 21, thereby transmitting the power of the motor shaft 11 to the gear member 2. Preferably, the first external gear 12 is inserted into the first internal gear 21 eccentrically with respect to the central axis of the first internal gear 21. In other words, the number of teeth or the diameter of the first external gear 12 is smaller than that of the first internal gear 21.

The second external gear 22 meshes with a gear (i.e., a crown gear 31) of the transmission unit 3 described later, and transmits power to the transmission unit 3.

Further, a bearing 26 is provided on the outer periphery of one end of the gear member 2 in the axial direction, and the bearing 26 is used to rotatably support the gear member 2 in the housing 4. Specifically, a boss 23 for providing a bearing 26 and a groove 24 for fixing a snap ring 25 are provided on the outer periphery of the gear member 2, and the bearing 26 is attached to the outer periphery of the gear member 2 via the boss 23 and the snap ring 25.

The transmission unit 3 of the present application includes a crown gear 31 and a sliding screw transmission pair 33. The crown gear 31 transmits the power of the gear member 2 to the transmission unit 3 by meshing with the second external gear 22 of the gear member 2. Further, a ball bearing 32 is press-fitted to the outer periphery of the crown gear 31, and the crown gear 31 is rotatably supported in the housing 4 via the ball bearing 32.

As a further feature of the present application, the present application employs a sliding screw drive pair 33 instead of the ball screw pair of fig. 1, which is comprised of a screw 95 and a nut 96. Specifically, as shown in fig. 5A to 5C, the sliding screw pair 33 of the present application includes a screw 34 connected to the crown gear 31 in a rotationally fixed manner and a nut 35 for converting the rotational motion of the screw 34 into a linear motion. The threaded spindle 34 is connected in a rotationally fixed manner to the crown gear 31, for example by way of a press fit. A nut 35 is located on the screw 34 to transmit torque. The assembly process of the sliding screw transmission pair 33 is much simpler than the condition of adopting a ball screw pair in the past, the manufacturing cost is low, and the later maintenance is simple.

As shown in fig. 6A to 6D, the nut 35 includes a plastic piece 36 and a metal piece 37, and the plastic piece 36 and the metal piece 37 are formed integrally by insert molding. As will be described later, the plastic member 36 and the screw 34 are driven to reduce the driving friction; further, by connecting the metal fitting 37 to the shift fork, the transmission can be performed efficiently while securing rigidity.

The plastic member 36 has an inner peripheral surface formed with an inner drive screw 361 for screw-driving with the outer drive screw 341 of the screw 34. The internal driving thread 361 may be a trapezoidal thread or a rectangular thread, and correspondingly, the external driving thread 341 of the screw 34 may be a trapezoidal thread or a rectangular thread.

The metal fitting 37 is manufactured by forging or the like, for example, and is provided on the outer periphery of the plastic member 36 by insert molding, and the metal fitting 37 is provided with a lug 371 for coupling with a shift fork, not shown. Specifically, two lugs 371 are located on opposite sides of the metal piece 37 for providing sufficient contact area for a shift fork, not shown, to grip.

When the motor 1 is operated, power is transmitted from the motor 1 to the shift fork via the gear member 2, the crown gear 31, the screw 34, and the nut 35, and a shift actuating function is performed. The end surface of one end of the metal piece 37 (i.e., the end where the lug 371 is not provided) is non-circular in shape, and in the illustrated embodiment is hexagonal. Accordingly, the rotation of the metal fitting 37 can be easily restricted by bringing the outer peripheral surface of the metal fitting 37 into contact with a rotation prevention pin, not shown, attached to the housing 4, and the nut 35 can be moved only linearly without being rotated.

In addition, the inner circumference of the metal piece 37 is provided with a groove 372, the outer circumference of the plastic piece 36 is provided with a protrusion 362, and the protrusion 362 is embedded into the groove 372 to prevent the metal piece 37 and the plastic piece 36 from moving relatively in the axial direction. In addition, as shown in FIG. 6D, the end surface of one end of the plastic member 36 (i.e., the end remote from the tab 371) has a non-circular shape, which in the illustrated embodiment is hexagonal. Accordingly, the overall shape of the protruding portion 362 on the outer periphery of the plastic member 36 and the concave groove 372 on the inner periphery of the metal member 37 can be hexagonal, and relative displacement between the plastic member 36 and the metal member 37 in the circumferential direction due to torque in the circumferential direction can be suppressed.

Some advantageous effects of the above-described embodiments of the present application will be briefly described below.

(i) The electric gear shifting actuating mechanism adopts the gear piece 2 which is brand-new and is provided with the first internal gear 21 and the second external gear 22, can replace a special motor with a general motor on the premise that the overall structure of the electric gear shifting actuating mechanism is not changed greatly, and can ensure that the gear shifting stroke/load is the same as the condition of using the special motor. Therefore, by using the universal motor and other mass-produced parts (such as a motor fixing screw, an anti-static cap and the like), the manufacturing cost of the electric gear shifting actuating mechanism can be greatly reduced, and the universal use of product parts is facilitated. In addition, the assembly process is basically the same as that of the traditional electric gear shifting actuating mechanism, and the manufacturing cost is favorably controlled.

(ii) This application adopts sliding screw transmission pair 33 to replace ball screw in the past vice, from this, can reduce manufacturing cost effectively, and can simplify the assembling process, and the maintenance in later stage also becomes simply. Further, by forming the nut 35 of the sliding screw pair 33 by the plastic member 36 and the metal member 37, the plastic member 36 can reduce the transmission friction, and the metal member 37 can ensure the rigidity of the entire nut 35.

(iii) Through the overall improvement, the manufacturing cost of the electric gear shifting actuating mechanism can be greatly reduced, and in a specific example, the manufacturing cost can be controlled within one third of that of the traditional electric gear shifting actuating mechanism.

The present application is not limited to the above-described embodiments, and those skilled in the art can make various modifications to the above-described embodiments of the present application without departing from the scope of the present application under the teaching of the present application.

Claims

1. An electric shift actuator, comprising:

the motor is provided with a motor shaft, and the output end of the motor shaft is provided with a first external gear;

a gear member including a first internal gear and a second external gear, the first external gear meshing with the first internal gear to form an internally meshing gear pair; and

and the second external gear is meshed with the gear of the transmission unit to transmit power to the transmission unit.

2. The electrical shift actuator of claim 1,

the first external gear has a diameter or number of teeth smaller than that of the first internal gear, and is inserted into the first internal gear eccentrically with respect to a central axis of the first internal gear.

3. The electrical shift actuator of claim 1 or 2,

the first external gear is integrally formed with an output end of the motor shaft,

the first internal gear is arranged at one axial end of the gear piece, the second external gear is arranged at the other axial end of the gear piece,

the first internal gear and the second external gear are arranged to be offset in the axial direction of the gear member.

4. The electrical shift actuator of claim 3,

the electrical shift actuator further includes a housing for at least partially housing the motor, the gear member, and the transmission unit,

a bearing is provided on an outer periphery of one end of the gear member in the axial direction, the bearing rotatably supporting the gear member within the housing.

5. The electrical shift actuator of claim 1,

the transmission unit comprises a sliding screw transmission pair,

the sliding screw transmission pair comprises a screw and a nut for converting the rotary motion of the screw into linear motion.

6. The electrical shift actuator of claim 5,

the nut includes working of plastics and metalwork, the inner periphery of working of plastics be formed with the transmission external screw thread of screw rod carries out screw thread drive's transmission internal thread, the metalwork is located the periphery of working of plastics, the metalwork is equipped with and is used for the lug of being connected with the shift fork of shifting.

7. The electrical shift actuator of claim 6,

the inner periphery of the metal piece is provided with a groove, the outer periphery of the plastic piece is provided with a protruding part, and the protruding part is embedded into the groove to prevent the metal piece and the plastic piece from moving axially relative to each other.

8. The electrical shift actuator of claim 6 or 7,

the plastic member and the metal member are formed integrally by insert molding.

9. The electrical shift actuator of claim 6 or 7,

one end of the metal piece is in a non-circular shape.

10. An electric bridge drive system, characterized in that it comprises an electric shift actuator according to any one of claims 1 to 9.