Gear shifting structure and electric drive axle

Abstract

The utility model provides a gear shifting structure and an electric drive axle, the gear shifting structure comprises a first transmission shaft and a second transmission shaft, the first transmission shaft is rotatably connected with a floating gear, the second transmission shaft is fixedly connected with a gear shifting gear, and the gear shifting gear is meshed with the floating gear. According to the gear shifting structure and the electric drive axle, the gaps are reserved between the corresponding keys and the key grooves between the synchronous sleeve and the floating gear, a certain redundant space is provided when the synchronous sleeve and the floating gear are in key connection, and it is ensured that the keys on the synchronous sleeve and the floating gear rapidly enter the corresponding key grooves; furthermore, a tooth-missing positioning structure is arranged between the synchronous sleeve and the floating gear, the concentricity among the floating gear, the synchronous sleeve and the first transmission shaft is improved through abutting of the tooth-missing positioning structure and an opposite key, and the situation that direct connection is achieved in a flat key and spline mode, large friction is generated between keys due to errors, and the service life of the floating gear is prolonged is avoided. And the service life of the gear shifting structure is influenced.

Description

Technical Field

[0001] The utility model relates to the field of electric drive axles, in particular to a gear shifting structure and an electric drive axle. Background Art

[0002] The electric drive axle refers to a whole composed of a motor, a gearbox, etc., which is used to drive the wheels. For example, the transmission mechanism disclosed in publication number CN202098528U includes a motor, a gearbox and a half-axle. The electric drive axle generates power from the motor and transmits the power to the gearbox connected to it. The gearbox drives the vehicle through the half-axle connected to it, and a shifting structure is set in the gearbox to adjust the gear position.

[0003] In the existing shift structure, the shift fork drives the synchronous sleeve to connect with the target floating gear to achieve the switching of the target gear position, wherein the synchronous sleeve and the target floating gear are connected by a flat key and a spline. There are certain errors in the processing and assembly process, which leads to greater friction between the keys of the two when they come into contact, thus affecting the service life of the shift structure. Utility Model Content

[0004] The utility model aims to provide a shifting structure and an electric drive axle which facilitate the connection between a synchronous sleeve and a target floating gear key during the shifting process and can extend the service life of the shifting structure.

[0005] In order to achieve the above object, the utility model provides a shift structure, comprising:

[0006] a first transmission shaft and a second transmission shaft, the first transmission shaft being rotatably connected to the floating gear, the second transmission shaft being fixedly connected to the shift gear, the shift gear being meshed with the floating gear;

[0007] A synchronous sleeve, wherein the synchronous sleeve is slidably connected between the first transmission shaft and the floating gear in an axial direction of the first transmission shaft, the synchronous sleeve is engaged with the first transmission shaft in a circumferential direction of the first transmission shaft, and the synchronous sleeve is key-connected with the floating gear;

[0008] A missing tooth positioning structure is provided between the synchronous sleeve and the floating gear. In the radial direction, the corresponding keys and keyways between the synchronous sleeve and the floating gear are clearance-matched, the missing tooth positioning structure and the relative keys are in contact with each other, and the floating gear, the synchronous sleeve and the first transmission shaft are concentrically arranged.

[0009] Preferably, there are multiple groups of keys on the synchronous sleeve or the floating gear, the number of keys in each group is multiple and arranged at intervals along the circumferential direction, a missing tooth positioning structure is provided between two adjacent groups of keys, a limited position surface is provided on the missing tooth positioning structure, and the limited position surface is abutted against the relative key top surface.

[0010] Preferably, the missing tooth positioning structure is a step formed by extending the outer wall of the floating gear toward the radial outside, the top surface of the step is a limiting surface, and the limiting surface abuts against the top surface of the relative key.

[0011] Preferably, both side surfaces of the missing tooth positioning structure located on the axial direction of the floating gear are inclined toward the center.

[0012] Preferably, a first key is provided on the inner wall of the synchronous sleeve, a first key groove is provided between adjacent first keys, the first keys are arranged at intervals along the circumference of the synchronous sleeve, a second key is provided on the outer wall of the floating gear, a second key groove is provided between adjacent second keys, the second keys are divided into a plurality of groups, each group has a plurality of second keys, the second keys in each group are arranged at intervals along the circumference of the floating gear, wherein the second keys of adjacent groups have tooth-missing interval areas reserved in the circumference of the floating gear, and the tooth-missing positioning structure is provided in the tooth-missing interval area.

[0013] Preferably, there are a plurality of the missing tooth positioning structures, and the missing tooth positioning structures are arranged at equal intervals around the circumference of the floating gear.

[0014] Preferably, the first keys are arranged at equal intervals along the circumference of the synchronization sleeve, and the second keys in each group are arranged at intervals along the circumference of the floating gear. The length of the first keyway and the second key in the circumference of the floating gear is a, and the length of the second keyway and the first key in the circumference of the floating gear is b.

[0015] Preferably, the length of the tooth-missing interval area is 3a+2b, and the length of the limiting surface in the circumferential direction of the floating gear is not less than a.

[0016] Preferably, the shifting structure further includes:

[0017] A fixing ring, wherein the fixing ring is fixedly connected to the first transmission shaft, wherein in the circumferential direction of the first transmission shaft, the fixing ring and the synchronizing sleeve are connected by a key, and in the axial direction of the first transmission shaft, the fixing ring and the synchronizing sleeve are connected by a sliding manner;

[0018] A shift fork, the synchronous sleeve is rotatably connected to the shift fork, the shift fork is movably mounted on the housing of the gearbox, and the shift fork is drivingly connected to the synchronous sleeve.

[0019] The utility model also provides an electric drive axle, comprising the above-mentioned shifting structure, and further comprising:

[0020] A gearbox, the gearbox comprising a housing, the first transmission shaft and the second transmission shaft being rotatably mounted in the housing;

[0021] A bridge housing, the gearbox and the bridge housing are connected;

[0022] An axial flux motor is drivingly connected to the first transmission shaft or the second transmission shaft.

[0023] Compared with the prior art, this technical solution has the following advantages:

[0024] The shifting structure and electric drive axle reserve gaps between the corresponding keys and keyways between the synchronous sleeve and the floating gear, provide a certain redundant space when the synchronous sleeve and the floating gear are key-connected, and ensure that the keys on both quickly enter the corresponding keyways. A missing tooth positioning structure is further provided between the synchronous sleeve and the floating gear, and the missing tooth positioning structure abuts against the corresponding key to improve the concentricity between the floating gear, the synchronous sleeve and the first transmission shaft, avoiding the problem of direct connection using flat keys and splines, which causes greater friction between keys due to errors and affects the service life of the shifting structure.

[0025] The present invention is further described below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is an overall schematic diagram of the transmission structure of the utility model;

[0027] Figure 2 This is a schematic diagram of the connection between the shift fork, the synchronization sleeve and the floating gear of the utility model;

[0028] Figure 3 For this utility model Figure 2 The enlarged schematic diagram at A in the middle;

[0029] Figure 4 It is a cross-sectional schematic diagram of the transmission structure of the utility model;

[0030] Figure 5 It is an overall schematic diagram of the electric drive bridge described in the utility model.

[0031] In the figure: 100, gearbox; 110, housing; 123, first transmission shaft; 124, second transmission shaft; 125, floating gear; 1251, missing tooth positioning structure; 12511, limiting surface; 1252, second key; 1253, second keyway; 1254, missing tooth spacing area; 1255, synchronizer ring; 126, shift gear; 127, synchronizer sleeve; 1271, first key; 1272, first keyway; 128, fixing ring; 129, shift fork; 200, axial flux motor; 300, bridge housing. DETAILED DESCRIPTION

[0032] The following description is used to disclose the utility model so that those skilled in the art can implement the utility model. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the utility model defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the utility model.

[0033] like Figure 1-4 As shown, the utility model provides a shifting structure, comprising:

[0034] A first transmission shaft 123 and a second transmission shaft 124;

[0035] A floating gear 125, wherein the floating gear 125 is rotatably connected to the first transmission shaft 123, and optionally, the floating gear 125 is mounted on the outer side of the first transmission shaft 123 via a roller bearing, and a synchronization ring 1255 is provided on one side of the floating gear 125 in the axial direction;

[0036] A shift gear 126, the shift gear 126 is fixedly connected to the second transmission shaft 124, the shift gear 126 is meshed with the floating gear 125, and optionally, the shift gear 126 can be fixedly connected to the outer side of the transmission shaft by means of a spline or the like;

[0037] A synchronization sleeve 127, wherein the synchronization sleeve 127 is movably arranged along the axial direction of the first transmission shaft 123, and in the circumferential direction of the first transmission shaft 123, the synchronization sleeve 127 and the first transmission shaft 123 are engaged, and the synchronization sleeve 127 and the synchronization ring 1255 are key-connected; in the axial direction of the first transmission shaft 123, the synchronization sleeve 127 and the first transmission shaft 123 are slidably connected, and the synchronization sleeve 127 and the synchronization ring 1255 are slidably connected;

[0038] The corresponding keys and keyways between the synchronization sleeve 127 and the synchronization ring 1255 are clearance-matched in the radial direction. Specifically, the corresponding key top surfaces and keyway bottom surfaces between the synchronization sleeve 127 and the synchronization ring 1255 are clearance-matched.

[0039] There are multiple groups of keys on the synchronization sleeve 127 or the synchronization ring 1255, and the number of keys in each group is multiple and arranged at intervals along the circumferential direction. A missing tooth positioning structure 1251 is provided between two adjacent groups of keys. A limited position surface 12511 is provided on the missing tooth positioning structure 1251, and the limited position surface 12511 is abutted against the relative key top surface. The floating gear 125, the synchronization sleeve 127 and the first transmission shaft 123 are concentrically arranged.

[0040] When in use, by adjusting the axial position of the synchronization sleeve 127 on the first transmission shaft 123, the synchronization sleeve 127 is keyed to the synchronization ring 1255 and engages with the first transmission shaft 123, so that the first transmission shaft 123 is synchronized with the target floating gear 125 through the floating gear 125, and the gear shifting operation is realized. A gap is reserved between the corresponding keys and keyways between the synchronization sleeve 127 and the floating gear 125, and a certain redundant space is provided when the synchronization sleeve 127 and the floating gear 125 are keyed to ensure that the keys on both quickly enter the corresponding keyways. A toothless positioning structure 1251 is further provided between the synchronization sleeve 127 and the floating gear 125, and the toothless positioning structure 1251 is abutted against the corresponding key to improve the concentricity between the floating gear 125, the synchronization sleeve 127 and the first transmission shaft 123, thereby avoiding the problem of direct connection using flat keys and splines, which causes greater friction between keys due to errors and affects the service life of the gear shifting structure.

[0041] See also Figure 2 The missing tooth positioning structure 1251 is a step formed by the outer wall of the synchronization ring 1255 extending radially outward, and the top surface of the step is the limiting surface 12511. Designing the missing tooth positioning structure 1251 as a step can facilitate the processing of the limiting surface 12511. The specific step provides a clearer positioning and reference for the processing process, which helps to stabilize the processing tool.

[0042] As a preferred embodiment, both side surfaces of the missing tooth positioning structure 1251 located in the axial direction of the synchronization ring 1255 are inclined toward the center, so that when the key on the synchronization sleeve 127 contacts the missing tooth positioning structure 1251, the inclined side surfaces of the missing tooth positioning structure 1251 can guide the key. In one embodiment of the utility model, the cross-sectional size of the missing tooth positioning structure 1251 gradually decreases in a manner away from the synchronization ring 1255, and the missing tooth positioning structure 1251 is a missing tooth positioning structure 1251 in the shape of a quadrangular pyramid.

[0043] See also Figure 2 and 3A first key 1271 is provided on the inner wall of the synchronization sleeve 127, and a first key groove 1272 is provided between adjacent first keys 1271. The first keys 1271 are arranged at equal intervals along the circumference of the synchronization sleeve 127. A second key 1252 is provided on the outer wall of the synchronization ring 1255, and a second key groove 1253 is provided between adjacent second keys 1252. The corresponding first key 1271 and the second key 1252 are fitted on the side surface of the synchronization ring 1255 in the circumferential direction. The second keys 1252 are divided into several groups, and the number of the second keys 1252 in each group is multiple. The second keys 1252 in each group are arranged at equal intervals along the circumference of the synchronization ring 1255, wherein the second keys 1252 of adjacent groups are reserved with a missing tooth spacing area 1254 in the circumference of the synchronization ring 1255, and the missing tooth positioning structure 1251 is arranged in the missing tooth spacing area 1254.

[0044] To ensure that the missing tooth positioning structure 1251 can squeeze the key on the synchronization sleeve 127 at multiple angles, further, the missing tooth positioning structure 1251 is multiple in number, and the missing tooth positioning structures 1251 are arranged at equal intervals around the circumference of the synchronization ring 1255. As a preferred embodiment, the second key 1252 is divided into three groups, and the number of the missing tooth positioning structures 1251 is three.

[0045] The length of the first keyway 1272 and the second key 1252 in the circumferential direction of the synchronizer ring 1255 is a, the length of the second keyway 1253 and the first key 1271 in the circumferential direction of the synchronizer ring 1255 is b, and the limiting surface 12511 on the toothless positioning structure 1251 is arranged along the circumferential direction of the synchronizer ring 1255, and the length of the limiting surface 12511 in the circumferential direction of the synchronizer ring 1255 is not less than a. When the synchronizer sleeve 127 and the synchronizer ring 1255 are key-connected, the limiting surface 12511 on the toothless positioning structure 1251 can fully abut against the key on the synchronizer sleeve 127 to achieve a concentric effect.

[0046] As a preferred embodiment, the length of the tooth-missing spacing area 1254 is 3a+2b.

[0047] See also Figure 3 The missing tooth positioning structure 1251 is located at the center of the missing tooth spacing area 1254 in the circumferential direction of the synchronization ring 1255, wherein the first key 1271 is a first key 1271 in the shape of a quadrangular pyramid, and the second key 1252 is a second key 1252 in the shape of a quadrangular pyramid.

[0048] See also Figure 4 , the shifting structure also includes:

[0049] The fixing ring 128 is fixedly connected to the first transmission shaft 123. In the circumferential direction of the first transmission shaft 123, the fixing ring 128 and the synchronization sleeve 127 are key-connected. In the axial direction of the first transmission shaft 123, the fixing ring 128 and the synchronization sleeve 127 are slidingly connected. Specifically, a third key is provided on the outer wall of the fixing ring 128, and the third key corresponds to the first key 1271 on the synchronization sleeve 127. The fixing ring 128 is connected to the outer side of the first transmission shaft 123 through a spline.

[0050] The shift fork 129 is rotatably connected to the synchronization sleeve 127 . The shift fork 129 is movably mounted on the housing of the gearbox. The shift fork 129 is drivingly connected to the synchronization sleeve 127 .

[0051] It should be noted that the shift fork 129 is connected to the shift actuator, and the shift actuator drives the shift fork 129 to move in the gearbox 100. This is an existing mature technology and is well known to those skilled in the art, and no detailed description is desired here.

[0052] In addition, the utility model also provides an electric drive axle, including the above-mentioned shifting structure, and further comprising:

[0053] The gearbox 100 includes a housing 110 and a gear set and a differential disposed in the housing 110, wherein the gear set includes a shifting structure;

[0054] A bridge housing 300, the bridge housing 300 is connected to the housing 110, and the portion of the housing 110 corresponding to the installation of the differential is located inside the bridge housing 300;

[0055] The axial flux motor 200 is arranged outside the housing 110 and is drivingly connected to the gear set. The axial flux motor 200 has the advantage of small thickness, so that the electric drive axle has the advantage of small volume.

[0056] Specifically, the gear set includes:

[0057] An input shaft and an intermediate shaft, wherein the input shaft is rotationally connected in the housing 110, the intermediate shaft is rotationally connected in the housing 110, the input shaft, the intermediate shaft and the differential are sequentially transmission-connected, and the axial flux motor 200 is drivingly connected to the input shaft.

[0058] As a preferred embodiment, the first transmission shaft 123 is an intermediate shaft, and the second transmission shaft 124 is an input shaft.

[0059] To sum up, the speed change mechanism reserves a gap between the corresponding keys and keyways between the synchronization sleeve 127 and the synchronization ring 1255, and provides a certain redundant space when the synchronization sleeve 127 and the synchronization ring 1255 are key-connected, ensuring that the keys on both quickly enter the corresponding keyways, and further provides a missing tooth positioning structure 1251 between adjacent groups of keys, and the limiting surface 12511 on the missing tooth positioning structure 1251 abuts against the top surface of the key opposite thereto, so as to improve the concentricity between the floating gear 125, the synchronization sleeve 127 and the first transmission shaft 123, thereby avoiding the problem in the traditional design that the floating gear 125 and the synchronization sleeve 127 are directly connected by means of flat keys and splines, and errors due to production processes and other reasons lead to greater friction between keys, thereby affecting the service life of the shifting structure.

[0060] The embodiments described above are only used to illustrate the technical ideas and features of the utility model, and their purpose is to enable technicians in this field to understand the content of the utility model and implement it accordingly. The patent application scope of the utility model cannot be limited only by this embodiment, that is, any equivalent changes or modifications made according to the spirit disclosed by the utility model still fall within the patent scope of the utility model.

Claims

1. A gear shifting structure, characterized in that: include: A first transmission shaft (123) and a second transmission shaft (124), wherein a floating gear (125) is rotatably connected to the first transmission shaft (123), and a shifting gear (126) is fixedly connected to the second transmission shaft (124), and the shifting gear (126) is meshed with the floating gear (125); A synchronous sleeve (127), wherein the synchronous sleeve (127) is slidably connected between the first transmission shaft (123) and the floating gear (125) in an axial direction of the first transmission shaft (123); in the circumferential direction of the first transmission shaft (123), the synchronous sleeve (127) and the first transmission shaft (123) are engaged; and the synchronous sleeve (127) and the floating gear (125) are key-connected; A missing tooth positioning structure (1251) is provided between the synchronization sleeve (127) and the floating gear (125). In the radial direction, the corresponding keys and keyways between the synchronization sleeve (127) and the floating gear (125) are clearance-matched. The missing tooth positioning structure (1251) and the relative keys are in contact with each other. The floating gear (125), the synchronization sleeve (127) and the first transmission shaft (123) are concentrically arranged.

2. The shift structure according to claim 1, characterized in that: There are multiple groups of keys on the synchronization sleeve (127) or the floating gear (125), and the number of keys in each group is multiple and arranged at intervals along the circumferential direction. A missing tooth positioning structure (1251) is provided between two adjacent groups of keys, and a limited position surface (12511) is provided on the missing tooth positioning structure (1251), and the limited position surface (12511) is in contact with the corresponding key top surface.

3. The shift structure according to claim 2, characterized in that: The missing tooth positioning structure (1251) is a step formed by the outer wall of the floating gear (125) extending radially outward, and the top surface of the step is a limiting surface (12511).

4. The shift structure according to claim 1, characterized in that: The two side surfaces of the missing tooth positioning structure (1251) located on the axial direction of the floating gear (125) are both inclined toward the center.

5. The shift structure according to claim 2, characterized in that: A first key (1271) is provided on the inner wall of the synchronization sleeve (127), and a first key groove (1272) is provided between adjacent first keys (1271). The first keys (1271) are arranged at intervals along the circumference of the synchronization sleeve (127). A second key (1252) is provided on the outer wall of the floating gear (125), and a second key groove (1253) is provided between adjacent second keys (1252). The second keys (1252) are divided into a plurality of groups, and each group has a plurality of second keys (1252). The second keys (1252) in each group are arranged at intervals along the circumference of the floating gear (125), wherein adjacent groups of the second keys (1252) have reserved tooth-missing spacing areas (1254) on the circumference of the floating gear (125), and the tooth-missing positioning structure (1251) is arranged in the tooth-missing spacing areas (1254).

6. The shift structure according to claim 5, characterized in that: The number of the missing tooth positioning structures (1251) is plural, and the missing tooth positioning structures (1251) are arranged at equal intervals around the circumference of the floating gear (125).

7. The shift structure according to claim 5, characterized in that: The first keys (1271) are arranged at equal intervals along the circumference of the synchronization sleeve (127), the length of the first keyway (1272) and the second key (1252) in the circumferential direction of the floating gear (125) is a, and the length of the second keyway (1253) and the first key (1271) in the circumferential direction of the floating gear (125) is b.

8. The shift structure according to claim 7, characterized in that: The length of the tooth-missing spacing area (1254) is 3a+2b, and the length of the limiting surface (12511) in the circumferential direction of the floating gear (125) is not less than a.

9. The shift structure according to claim 1, characterized in that: Also includes: a fixing ring (128), the fixing ring (128) being fixedly connected to the first transmission shaft (123); in the circumferential direction of the first transmission shaft (123), the fixing ring (128) and the synchronizing sleeve (127) are key-connected; in the axial direction of the first transmission shaft (123), the fixing ring (128) and the synchronizing sleeve (127) are slidingly connected; A shift fork (129), the synchronous sleeve (127) is rotatably connected to the shift fork (129), the shift fork (129) is movably mounted on a housing (110) of a gearbox (100), and the shift fork (129) is drivingly connected to the synchronous sleeve (127).

10. An electric drive bridge, characterized in that: The gear shifting structure according to any one of claims 1 to 9 above further comprises: A gearbox (100), the gearbox (100) comprising a housing (110), the first transmission shaft (123) and the second transmission shaft (124) being rotatably mounted in the housing (110); A bridge housing (300), the gearbox (100) and the bridge housing (300) being connected; An axial flux motor (200) is drivingly connected to the second transmission shaft (124).

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