Shifting fork assembly

Abstract

The invention relates to a shifting fork assembly which comprises a shifting fork (100) and a shifting fork (200). The mounting seat (200) is fixedly connected with the shifting fork (100) and is provided with a through hole (210); the screw rod (300) is arranged in the through hole (210) in a penetrating manner; the rolling body unit (400) comprises a base (410) and a first ball (420), the base (410) is fixedly connected with the mounting base (200), a containing groove (411) is formed in the base (410), one part of the first ball (420) is contained in the containing groove (411), the other part of the first ball (420) penetrates out of the containing groove (411) and abuts against the threaded groove of the screw (300), and the first ball (420) can freely rotate between the containing groove and the threaded groove. According to the gear shifting fork assembly, by means of the combination of the screw and the rolling body units, the number of parts is small, the structure is simple, assembling is easy, and therefore cost is low.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle parts, and in particular to a shift fork assembly. Background Art

[0002] The shift fork assembly is applied to devices that require shifting, such as a gearbox, a transfer case, a disconnect mechanism, etc., to achieve the shifting function. In the prior art, the shift fork assembly is driven by a hydraulic mechanism, a shift hub or a ball screw, and the cost of these is very high. Summary of the invention

[0003] The object of the present invention is to provide a shift fork assembly with lower cost.

[0004] According to one aspect of the present invention, there is provided a shift fork assembly, which includes: a shift fork; a mounting seat, which is fixedly connected to the shift fork and is provided with a through hole; a screw rod, which is inserted into the through hole; and a rolling element unit, which includes a base and a first ball, the base is fixedly connected to the mounting seat, and the base has a receiving groove inside, a part of the first ball is accommodated in the receiving groove, and the other part thereof passes through the receiving groove and abuts against the thread groove of the screw rod, and the first ball can rotate freely between the receiving groove and the thread groove.

[0005] According to an embodiment of the present invention, the rolling element unit further comprises a plurality of second balls, each of which is freely rotatably abutted against the receiving groove and freely rotatably abutted against the first ball, and the diameter of the second ball is smaller than the diameter of the first ball.

[0006] According to an embodiment of the present invention, the shift fork assembly comprises a plurality of rolling element units, which are respectively located at different circumferential positions in the circumferential direction and / or at different axial positions in the axial direction.

[0007] According to an embodiment of the present invention, the mounting seat is provided with a through hole, the through hole is communicated with the through hole, and the rolling element unit is penetrated in the through hole.

[0008] According to an embodiment of the present invention, the rolling element unit further includes a locking portion connected to the base and configured to prevent the plurality of second balls from falling out of the receiving groove.

[0009] According to an embodiment of the present invention, the locking portion is connected to the base at the opening of the receiving groove and is configured as an annular flange.

[0010] According to an embodiment of the present invention, the shift fork assembly further comprises a support shaft, which is fixedly connected to the shift fork and arranged parallel to the screw rod.

[0011] According to an embodiment of the present invention, the support shaft has a support shaft body and wear-resistant components, and the wear-resistant components are installed at both ends of the support shaft body.

[0012] The shift fork assembly of the present invention utilizes a combination of a screw and a rolling element unit, has fewer parts, a simple structure, and has low requirements on the accuracy and surface roughness of the screw thread groove. The screw is easy to manufacture, so the cost is low. At the same time, the first ball and the second ball are both confined in the receiving groove of the rolling element unit, and will not roll out during installation and movement, thereby improving the convenience of assembly and the life of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a perspective view showing a shift fork assembly according to an embodiment of the present invention.

[0014] Figure 2 is an exploded view showing a shift fork assembly according to an embodiment of the present invention.

[0015] Figure 3 is a cross-sectional perspective view showing a shift fork assembly according to an embodiment of the present invention.

[0016] Figure 4 is a cross-sectional view showing a rolling element unit according to an embodiment of the present invention.

[0017] Numbers in the figure:

[0018] 100, shift fork; 110, shift fork foot; 111, free end; 112, connecting part; 113, jack; 120, wear-resistant sheet;

[0019] 200, mounting seat; 210, through hole; 220, perforation;

[0020] 300, screw;

[0021] 400, rolling element unit; 410, base; 411, receiving groove; 420, first rolling ball; 430, second rolling ball; 440, locking portion;

[0022] 500, bearings;

[0023] 600, support shaft; 610, support shaft body; 620, wear-resistant component; 611, small diameter portion; 612, large diameter portion;

[0024] 700. Magnet mounting member; 710. Magnet. DETAILED DESCRIPTION

[0025] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. The described embodiments are only possible technical implementations of the present invention, not all possible implementations. Those skilled in the art can fully combine the embodiments of the present invention to obtain other embodiments without creative work, and these embodiments are also within the scope of protection of the present invention.

[0026] Herein, the “axial direction” refers to the direction of the central axis of the screw, the “circumferential direction” refers to the direction extending around the screw, and the “radial direction” refers to the direction perpendicular to the central axis.

[0027] Figure 1 is a perspective view showing a shift fork assembly according to an embodiment of the present invention, Figure 2 is an exploded view showing a shift fork assembly according to an embodiment of the present invention, Figure 3 is a cross-sectional perspective view showing a shift fork assembly according to an embodiment of the present invention.

[0028] like Figures 1 to 3 As shown, the shift fork assembly includes a shift fork 100, a mounting seat 200, a screw rod 300 and a rolling element unit 400. The mounting seat 200 is fixedly connected to the shift fork 100 and is provided with a through hole 210, and the screw rod 300 is inserted into the through hole 210. The rolling element unit 400 includes a base 410 and a first ball 420. The base 410 is fixedly connected to the mounting seat 200, and the base 410 has a receiving groove 411 inside. A part of the first ball 420 is accommodated in the receiving groove 411, and another part of the first ball 420 extends out of the receiving groove 411 and abuts against the thread groove of the screw rod 300, and the first ball 420 can rotate freely between the receiving groove 411 and the thread groove.

[0029] When the screw rod 300 rotates, the first ball 420 abutting against the thread groove is pushed to move linearly in the axial direction under the extrusion force of the thread. Since the mounting seat 200 is fixedly connected to the base 410 accommodating the first ball 420, and the shift fork 100 is fixedly connected to the mounting seat 200, the shift fork 100 moves linearly in the axial direction under the drive of the first ball 420, thereby realizing the shifting function.

[0030] Compared with the ball screw transmission method in the prior art, the shift fork assembly of the present invention utilizes a combination of a screw rod 300 and a rolling element unit 400, has fewer parts, a simple structure, and is easy to assemble, so the cost is low.

[0031] The shift fork 100 has two shift fork legs 110, and a fork opening is defined between the two shift fork legs 110. For example, the fork opening is in an arched shape. The free end 111 of the shift fork leg 110 and the axial sides of the connecting portion 112 of the two shift fork legs 110 are constructed as planes, such as machined surfaces, so as to have good flatness. The free end 111 and the connecting portion 112 are provided with a socket 113 penetrating in the axial direction, for example, the number of the sockets 113 is two. A wear-resistant sheet 120 made of, for example, plastic material is installed at the free end 111 and the connecting portion 112. The two pins of the wear-resistant sheet 120 can be inserted into the two sockets 113 one by one, and the pins and the sockets 113 are interference fit, and then the two pins of the wear-resistant sheet 120 are connected together by ultrasonic welding to ensure that the wear-resistant sheet 120 will not fall off during the movement of the shift fork.

[0032] The shift fork 100 can be mounted on the synchronizer sleeve to shift the synchronizer sleeve to connect or disconnect different transmission gear pairs, thereby achieving a shifting function. The wear-resistant sheet 120 can protect the shift fork 100, for example, to prevent the shift fork 100 from being worn and to relieve the collision between the synchronizer sleeve and the shift fork 100.

[0033] The mounting seat 200 may be substantially cylindrical, and the axis of the cylindrical mounting seat 200 is perpendicular to the plane where the two fork legs 110 of the fork 100 are located. The mounting seat 200 is fixedly connected to the fork 100, for example, the mounting seat 200 and the fork 100 are formed integrally.

[0034] The mounting seat 200 has a through hole 210 extending in the axial direction, a middle portion of the screw rod 300 is accommodated in the through hole 210, and both ends of the screw rod 300 extend out of the through hole 210. For example, the through hole 210 has a cylindrical inner surface.

[0035] Bearings 500 are respectively installed at both ends of the screw 300. The bearings 500 can be installed in the bearing holes in the gearbox housing, and the bearings 500 are interference fit with the bearing holes. The screw 300 can be connected to the rotating shaft of the motor to transmit the rotation of the motor to the screw 300. Under the support of the bearings 500, the screw 300 only rotates, and its position in the gearbox remains unchanged.

[0036] The base 410 has a receiving groove 411, and the receiving groove 411 has, for example, an approximately hemispherical inner surface. The base 410 is fixedly mounted on the mounting seat 200, and the mounting seat 200 is fixedly connected to the shift fork 100. Therefore, the base 410 and the shift fork 100 are relatively stationary.

[0037] Figure 4 2 is a cross-sectional view showing a rolling element unit according to an embodiment of the present invention. Figure 4As shown, the rolling body unit 400 also includes a plurality of second balls 430. The diameter of the first ball 420 is greater than the diameter of the second ball 430. Each second ball 430 can abut against the inner surface of the receiving groove 411 and abut against the first ball 420. In other words, the second ball 430 is in point contact with the inner surface of the receiving groove 411 and the outer surface of the first ball 420 at the same time. Therefore, the friction impedance between the first ball 420 and the screw 300 is reduced. The plurality of second balls 430 and the first ball 420 can all rotate freely. Thereby, when the screw 300 rotates, driven by the first ball 420, the fork 100 can move smoothly in a straight line along the axial direction together with the mounting seat 200. The first ball 420 and the second ball 430 can be steel balls.

[0038] The shift fork assembly includes a plurality of rolling element units 400. The number of rolling element units 400 can be determined according to the load-bearing capacity of the rolling element units 400 and the magnitude of the driving force. Figures 1 to 3 In the illustrated embodiment, the shift fork assembly includes three rolling element units 400. In the circumferential direction, the plurality of rolling element units 400 are respectively located at different circumferential positions, and / or in the axial direction, the plurality of rolling element units 400 are respectively located at different axial positions, so as to ensure that the screw rod 300 is subjected to balanced forces in the circumferential direction. Thus, it can be ensured that the movement of the shift fork 100 will not be stuck.

[0039] The mounting seat 200 has a through hole 220, which is connected to the through hole 210, and the rolling body unit 400 is inserted into the through hole 220. During the assembly process, the rolling body unit 400 can be inserted into the through hole 220 from the outside of the mounting seat 200, and the first ball 420 abuts against the threaded groove. Thereby, the installation of the rolling body unit 400 can be facilitated. The through hole 220 can extend perpendicularly to the axial direction and have a cylindrical inner surface. For example, the base 410 is interference fit with the through hole 220, so that the base 410 is fixedly connected to the mounting seat 200.

[0040] The rolling element unit 400 further includes a stopper 440, which is connected to the base 410 and is configured to prevent the plurality of second balls 430 from falling out of the receiving groove. The stopper 440 is connected to the base 410 at the opening of the receiving groove and is configured as an annular flange. Further, the stopper 440 can be configured to prevent the entire first ball 420 from falling out of the receiving groove 411. The inner diameter of the annular flange is smaller than the diameter of the first ball 420. The stopper 440 can be connected to the base 410 in one piece.

[0041] The shift fork assembly also includes a support shaft 600, which is fixedly connected to the fork 100 and arranged parallel to the screw rod 300. The support shaft 600 matches the shaft hole of the housing, and the support shaft 600 can move in the axial direction relative to the shaft hole. The support shaft 600 and the screw rod 300 are arranged in a double parallel shaft type, and the support shaft 600 plays a supporting role and bears the main shifting load together with the fork 100. Therefore, the screw rod 300 is subjected to less force and is not easily deformed, ensuring that the shift fork assembly will not get stuck.

[0042] The support shaft 600 includes a support shaft body 610 and a wear-resistant component 620, and the wear-resistant component 620 is located at both ends of the support shaft body 610. The support shaft body 610 has a cylindrical small diameter portion 611 and a cylindrical large diameter portion 612, the small diameter portion 611 is respectively located at both ends of the support shaft body 610, and the large diameter portion 612 is located between the two small diameter portions 611. The wear-resistant component 620 can be sleeved on the small diameter portion 611, and has an interference fit with the small diameter portion 611, and the wear-resistant component 620 can be pressed onto the small diameter portion 611. The wear-resistant component 620 is used to cooperate with the shaft hole of the housing to prevent the support shaft 600 from being worn. For example, the wear-resistant component 620 is made of plastic. The support shaft body 610, the fork 100 and the mounting seat 200 can be formed integrally.

[0043] The shift fork assembly further includes a magnet mounting member 700 for mounting a magnet, and the magnet mounting member 700 is fixedly mounted to the support shaft 600. The magnet 710 is used to cooperate with a sensor mounted on, for example, a transmission housing to detect the position of the shift fork 100. The magnet 710 can be mounted on the magnet mounting member 700 by screws. The magnet mounting member 700 can be formed integrally with the support shaft body 610.

[0044] The above are only some embodiments of the present application, and do not limit the present application in any form. Any simple modification, equivalent changes and modifications made to the above embodiments still fall within the scope of protection of the technical solution of the present application.

Claims

1. A shift fork assembly, comprising: Fork(100); A mounting seat (200) which is fixedly connected to the shift fork (100) and is provided with a through hole (210); A screw rod (300) is inserted into the through hole (210); as well as A rolling element unit (400) comprising a base (410) which is fixedly connected to the mounting base (200), and the base (410) has a receiving groove (411) inside, and A first ball (420) has a portion contained in the containing groove (411) and another portion passing through the containing groove (411) and resting against the thread groove of the screw rod (300). The first ball (420) can rotate freely between the containing groove (411) and the thread groove.

2. The shift fork assembly according to claim 1, wherein: The rolling body unit (400) further comprises a plurality of second balls (430), each of the second balls (430) being freely rotatably abutted against the receiving groove (411) and freely rotatably abutted against the first ball (420), and the diameter of the second ball (430) being smaller than the diameter of the first ball (420).

3. The shift fork assembly according to claim 1, wherein: The shift fork assembly comprises a plurality of rolling element units (400), In the circumferential direction, the plurality of rolling element units (400) are respectively located at different circumferential positions, and / or In the axial direction, the plurality of rolling element units (400) are respectively located at different axial positions.

4. The shift fork assembly according to claim 1, wherein: The mounting seat (200) is provided with a through hole (220), the through hole (220) is connected to the through hole (210), and the rolling body unit (400) is penetrated in the through hole (220).

5. The shift fork assembly according to claim 2, wherein: The rolling element unit (400) further comprises: A locking portion (440) is connected to the base (410) and is configured to prevent the plurality of second rolling balls (430) from falling out of the receiving groove (411).

6. The shift fork assembly according to claim 5, wherein: The locking portion (440) is connected to the base (410) at the opening of the accommodating groove (411) and is configured as an annular flange.

7. The shift fork assembly according to claim 1, further comprising: A support shaft (600) is fixedly connected to the shift fork (100) and is arranged parallel to the screw rod (300).

8. The shift fork assembly according to claim 7, wherein: The support shaft (600) comprises a support shaft body (610) and a wear-resistant component (620), wherein the wear-resistant component (620) is installed at both ends of the support shaft body (610).

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