阅读说明：本技术 电动车辆amt变速箱用摇臂式换挡驱动机构 (Rocker arm type gear shifting driving mechanism for AMT gearbox of electric vehicle ) 是由 陈永辉 宋文荣 于 2020-12-31 设计创作，主要内容包括：本发明涉及一种新能源汽车,具体涉及一种电动车辆AMT变速箱用摇臂式换挡驱动机构。一种电动车辆AMT变速箱用摇臂式换挡驱动机构,包括驱动电机、传动件、挡拨杆联动块、固定轴和挡拨杆,在驱动电机作用下所述传动件带动所述挡拨杆联动块以自转轴线为中心转动,所述挡拨杆联动块偏离所述自转轴线,所述固定轴轴线与所述自转轴线平行设置,所述挡拨杆一端与所述固定轴可转动固定,所述挡拨杆偏离固定轴处设有沿挡拨杆长度方向设置的条形孔,所述挡拨杆联动块一端伸入条形孔内,所述挡拨杆联动块另一端与所述传动件联动。本发明具有传动力矩大,能有效实现换挡的进行,能使变速箱内齿轮缓冲减震,能延长变速箱使用寿命,能保证变速箱正常使用的优点。(The invention relates to a new energy automobile, in particular to a rocker arm type gear shifting driving mechanism for an AMT (automated mechanical transmission) gearbox of an electric vehicle. The utility model provides an electric vehicle AMT is rocking arm formula actuating mechanism that shifts for gearbox, includes driving motor, driving medium, keeps off driving lever linkage piece, fixed axle and keeps off the driving lever, under the driving motor effect the driving medium drives it uses rotation from the pivot line as the center to keep off driving lever linkage piece, it is skew to keep off driving lever linkage piece from the pivot line, the fixed axle axis with pivot line parallel arrangement from the pivot line, keep off driving lever one end with the fixed axle is rotatable fixed, it is equipped with along keeping off the bar hole that driving lever length direction set up to keep off the skew fixed axle department of driving lever, it stretches into in the bar hole to keep off driving lever linkage piece one end, keep off driving lever linkage piece other end with the driving medium linkage. The invention has the advantages of large transmission torque, effective gear shifting, gear buffering and damping in the gear box, prolonged service life of the gear box and ensured normal use of the gear box.)

1. The rocker arm type gear shifting driving mechanism for the AMT gearbox of the electric vehicle is characterized by comprising a driving motor, a driving medium for receiving the torque of the driving motor, a shifting rod blocking linkage block, a fixed shaft and a shifting rod blocking part, wherein the driving medium drives the shifting rod blocking linkage block to rotate by taking an automatic rotating axis as a center under the action of the driving motor, the shifting rod blocking linkage block is deviated from the automatic rotating axis, the axis of the fixed shaft is parallel to the automatic rotating axis, one end of the shifting rod blocking part is rotatably fixed with the fixed shaft, the other end of the shifting rod blocking part extends to the side far away from the fixed shaft, a strip-shaped hole arranged along the length direction of the shifting rod is formed in the position of the deviating fixed shaft of the shifting rod blocking part, one end of the shifting rod blocking part extends into the strip-shaped hole, and the other.

2. The rocker arm type gearshift driving mechanism of an AMT gearbox of an electric vehicle as set forth in claim 1, wherein a swing link is fixed to the transmission member, one end of the swing link is fixed to the transmission member, the other end of the swing link extends away from the transmission member and is rotatably fixed to the gearshift lever linkage block, and when the transmission member rotates, the swing link swings about the rotation axis to move the gearshift lever linkage block.

3. The rocker arm type gear shifting driving mechanism for the AMT gearbox of the electric vehicle as recited in claim 1, wherein said deflector rod linkage block is arranged in a circular shape at the outer edge of the cross section of the inner end of the strip-shaped hole, and said strip-shaped hole is in a kidney-shaped hole structure with circular arc-shaped ends.

4. The rocker arm type shift drive mechanism for an AMT gearbox of an electric vehicle according to claim 1, wherein said rotation axis is relatively located between said fixed shaft and said strip-shaped hole.

5. The rocker arm type gear shifting driving mechanism for the AMT gearbox of the electric vehicle as recited in claim 1, wherein said driving motor output shaft is provided with a starting gear, and said transmission member is provided with a tooth structure engaged with said starting gear; an arc-shaped groove which gives way to the starting gear is arranged at the position, deviating from the self-rotating axis, of the transmission piece, the circle center of the arc-shaped groove is positioned on the self-rotating axis, and the tooth structure is arranged on the wall of the arc-shaped groove; the tooth structure is arranged on the wall of the arc-shaped groove deviating from the rotation axis.

6. The rocker arm type gear shifting driving mechanism of an AMT gearbox of an electric vehicle according to claim 1, wherein the driving member is composed of a first driving member and a second driving member, the driving lever linkage block is fixed with the first driving member, the second driving member receives driving motor torque, a linkage gap is arranged between the first driving member and the second driving member, a plurality of first convex bodies are arranged at intervals in the linkage gap, an elastic buffer block is further arranged in the linkage gap, the elastic buffer block is provided with a plurality of buffer parts which can be matched between adjacent first convex bodies of the linkage gap, the first convex bodies are fixed with the first driving member or the second driving member, and the second driving member rotates to push the first driving member to rotate through the elastic buffer block.

7. The rocker arm type gear shifting driving mechanism of the AMT gearbox of the electric vehicle as recited in claim 6, wherein said first transmission member and said second transmission member are sleeved with each other, said elastic buffer block is composed of a buffer block ring portion disposed annularly and said buffer portion fixed on said buffer block ring portion, said elastic buffer block is sleeved between said first transmission member and said second transmission member.

8. The rocker arm type gear shifting driving mechanism of the AMT gearbox of the electric vehicle as recited in claim 6, wherein an inner limiting portion is disposed at the middle of the first transmission member, the first transmission member is provided with a plurality of second protrusions annularly spaced around the inner limiting portion, a plurality of first protrusions are annularly spaced on the second transmission member, the elastic buffer block is sleeved outside the inner limiting portion, a first positioning groove matching with the second protrusion is formed on the buffer portion of the elastic buffer block, and a second positioning groove matching with the first protrusion is formed between two adjacent buffer portions; the first transmission piece or the second transmission piece is provided with an annular outer limiting part, and the elastic buffer block is positioned between the outer limiting part and the inner limiting part.

9. The rocker arm type gear shifting driving mechanism for an AMT gearbox of an electric vehicle according to claim 1, wherein a positioning shaft is arranged on the transmission member, the positioning shaft is coaxial with the rotation axis, the blocking lever is provided with an arc-shaped matching groove, the arc-shaped opening of the matching groove faces the fixed shaft, and one end of the positioning shaft, which is far away from the transmission member, is matched in the matching groove.

10. The rocker arm type gear shifting driving mechanism for an AMT gearbox of an electric vehicle according to claim 9, wherein the driving motor is fixed with a housing, two driving members are arranged in the housing, the two driving members are linked with a shift lever respectively, each driving member is provided with a positioning shaft, the two positioning shafts are coaxially arranged, each shift lever is provided with the matching groove, the adjacent end parts of the two positioning shafts are provided with a concave part and a convex part which are matched with each other, and the convex part extends into the concave part; the groove wall formed by the concave part is in clearance fit with the outer surface of the convex part; the two-gear shifting rod comprises a fixed part sleeved outside the fixed shaft and a shifting part provided with a strip-shaped hole, and the fixed parts of the two-gear shifting rod are attached to each other; the end faces of the two fixing parts, which are close to each other, are provided with corresponding and communicated abdicating grooves, lubricating oil is arranged in the abdicating grooves, and the abdicating grooves are annular and surround the circumferential outer side of the fixing shaft; the two-gear shifting rod can be rotatably fixed on the same fixed shaft.

Technical Field

The invention relates to a new energy automobile, in particular to a rocker arm type gear shifting driving mechanism for an AMT (automated mechanical transmission) gearbox of an electric vehicle.

Background

The gearbox includes AMT gearshift and speed change transmission mechanism, moves through AMT gearshift drive speed change transmission mechanism's shift fork to realize shifting. Wherein, current AMT actuating mechanism that shifts structure is very complicated, and transmission torque is not enough, and the stability in use is poor, need use high-power motor, perhaps increases among the AMT gearshift driving motor's the reduction ratio, can cause AMT gearshift volume grow, and AMT gearshift's spare part atress is bigger, and AMT gearshift's spare part is changeed and is damaged.

A plurality of gears are arranged in the gearbox, and dynamic synchronous deviation and instantaneous tooth engagement can happen occasionally during gear shifting; the gear can produce vibrations this moment to transmit power for AMT gearshift's fender driving lever through the shift fork, if AMT gearshift's fender driving lever does not match buffering damper, the condition of tooth can be had to the gear in the gearbox so, not only can cause gearbox gear excessive wear and tear, life is shorter, more serious damage gearbox internal gear, leads to gearbox function failure, still leads to the emergence of incident easily.

Disclosure of Invention

The invention aims to provide a rocker arm type gear shifting driving mechanism for an AMT (automated mechanical transmission) of an electric vehicle, which has larger transmission torque and can effectively realize gear shifting.

In order to achieve the purpose, the invention adopts the following technical scheme: the utility model provides an electric vehicle AMT is rocking arm formula actuating mechanism that shifts for gearbox, includes driving motor, is used for receiving driving motor moment's driving medium, keeps off driving lever linkage block, fixed axle and keeps off the driving lever, under the driving motor effect the driving medium drives it uses rotation axis to rotate as the center to keep off driving lever linkage block, it is skew to keep off driving lever linkage block from rotation axis, the fixed axle axis with rotation axis parallel arrangement, keep off driving lever one end with the fixed axle is rotatable fixed, keep off the driving lever other end and extend to keeping away from fixed axle side, it is equipped with the bar hole that sets up along keeping off driving lever length direction to keep off the skew fixed axle department of driving lever, it stretches into in the bar hole to keep off driving lever linkage block one end, keep off the driving lever linkage block other end with the driving medium linkage.

The output shaft of the driving motor rotates to enable the transmission piece to drive the shifting rod linkage block to move, so that the shifting rod linkage block moves in the strip-shaped hole of the shifting rod and pushes the shifting rod to swing with the fixed shaft as the center, and therefore the shifting rod is contacted with the shifting fork to achieve shifting. Compared with the existing gear shifting driving mechanism of the gearbox, the gear shifting driving mechanism of the gearbox has larger transmission torque, can realize effective gear shifting, can improve the use stability of the gearbox, and has longer service life.

Preferably, a swing rod is fixed on the transmission piece, one end of the swing rod is fixed with the transmission piece, the other end of the swing rod extends to the side far away from the transmission piece and is rotatably fixed with the driving blocking lever linkage block, and when the transmission piece rotates, the swing rod swings around the rotation axis to enable the driving blocking lever linkage block to move. The transmission part can be made smaller by the arrangement, the driving lever blocking linkage block can be rotatably fixed on the swing rod, resistance in the moving process of the driving lever blocking linkage block can be reduced, abrasion of the driving lever blocking linkage block can be reduced, and the service life of the transmission part can be prolonged.

Preferably, the outer edge of the cross section of the deflector rod linkage block, which is positioned at the inner end part of the strip-shaped hole, is circularly arranged, and the strip-shaped hole is of a kidney-shaped hole structure with two circular arc-shaped ends. The two ends of the strip-shaped hole are arc-shaped, the end part of the blocking deflector rod linkage block is circular, the contact area between the blocking deflector rod linkage block and the blocking deflector rod when the blocking deflector rod linkage block moves can be increased, and the blocking deflector rod linkage block can better push the blocking deflector rod to move.

Preferably, the rotation axis is relatively located between the fixed shaft and the strip-shaped hole. Above-mentioned setting is so that keep off the driving lever and have longer arm length, and it is littleer to enable to keep off the driving lever displacement angle, keeps off the driving lever stability higher to guarantee the reliability of shifting.

Preferably, a starting gear is arranged on an output shaft of the driving motor, and a tooth structure meshed with the starting gear is arranged on the transmission part; an arc-shaped groove which gives way to the starting gear is arranged at the position, deviating from the self-rotating axis, of the transmission piece, the circle center of the arc-shaped groove is positioned on the self-rotating axis, and the tooth structure is arranged on the wall of the arc-shaped groove; the tooth structure is arranged on the wall of the arc-shaped groove deviating from the rotation axis. Wherein, set up the arc wall in order to restrict the turned angle of driving medium. One side of the arc-shaped groove, which is far away from the axis of the rotation shaft, is arranged on a tooth structure meshed with the starting gear, so that the transmission of force is increased, and the output torque output to the gear shifting rod is larger.

Preferably, the transmission part comprises a first transmission part and a second transmission part, the driving lever linkage block is fixed to the first transmission part, the second transmission part receives the torque of the driving motor, a linkage gap is formed between the first transmission part and the second transmission part, a plurality of first convex bodies arranged at intervals are arranged in the linkage gap, an elastic buffer block is further arranged in the linkage gap, the elastic buffer block is provided with a plurality of buffer parts capable of being matched between adjacent first convex bodies in the linkage gap, the first convex bodies are fixed to the first transmission part or the second transmission part, and the second transmission part rotates to push the first transmission part to rotate through the elastic buffer block.

The transmission part comprises two parts, one part is used for receiving the torque of the driving motor, the other part is used for driving the shifting rod linkage block to move, an elastic buffer block is arranged between the two parts, and the elastic buffer block plays a role in shock absorption. When the gear in the gearbox bites the teeth, the force generated by the vibration of the gear in the gearbox is transmitted to the shift lever through the shift fork and then transmitted to the first transmission piece, so that the elastic buffer block is deformed, the second transmission piece is still, and the output shaft of the driving motor cannot be stressed. According to the invention, the elastic buffer block is arranged to reduce the impact and the vibration of the gear in the gearbox, so that the gear is prevented from being damaged, the service life of the gearbox is prolonged, and the normal use of the gear shifting function of the gearbox is ensured.

Preferably, the first transmission member and the second transmission member are sleeved with each other, the elastic buffer block is composed of a buffer block ring portion arranged in an annular shape and a buffer portion fixed on the buffer block ring portion, and the elastic buffer block is sleeved between the first transmission member and the second transmission member. The arrangement is such that the structure of the invention is more compact, so that the AMT can be made smaller.

Preferably, an inner limiting part is arranged in the middle of the first transmission part, the first transmission part is provided with a plurality of second convex bodies which are annularly arranged at intervals by taking the inner limiting part as a center, the plurality of first convex bodies are annularly arranged on the second transmission part at intervals, the elastic buffer block is sleeved outside the inner limiting part, a first positioning groove matched with the second convex bodies is formed in the buffer part of the elastic buffer block, and a second positioning groove matched with the first convex bodies is formed between every two adjacent buffer parts; the first transmission piece or the second transmission piece is provided with an annular outer limiting part, and the elastic buffer block is positioned between the outer limiting part and the inner limiting part. The inner limiting part is used for positioning the annular elastic buffer block, and the outer limiting part is used for protecting the elastic buffer block and other structures in the linkage gap. The arrangement is such that the structure of the invention is more compact, so that the AMT can be made smaller.

Preferably, the transmission part is provided with a positioning shaft, the positioning shaft is coaxial with the rotation axis, the blocking deflector rod is provided with an arc-shaped matching groove, an arc opening of the matching groove faces the fixed shaft, and one end, far away from the transmission part, of the positioning shaft is matched in the matching groove. The positioning shaft is used for supporting and guiding the blocking deflector rod so that the blocking deflector rod can move more stably.

Preferably, the driving motor is fixed with the shell, two transmission parts are arranged in the shell, the two transmission parts are respectively linked with a blocking deflector rod, the two transmission parts are respectively provided with a positioning shaft, the two positioning shafts are coaxially arranged, the two blocking deflector rods are respectively provided with the matching grooves, the end parts of the two positioning shafts, which are close to each other, are provided with a concave part and a convex part which are matched with each other, and the convex part extends into the concave part; the groove wall formed by the concave part is in clearance fit with the outer surface of the convex part; the two-gear shifting rod comprises a fixed part sleeved outside the fixed shaft and a shifting part provided with a strip-shaped hole, and the fixed parts of the two-gear shifting rod are attached to each other; the end faces of the two fixing parts, which are close to each other, are provided with corresponding and communicated abdicating grooves, lubricating oil is arranged in the abdicating grooves, and the abdicating grooves are annular and surround the circumferential outer side of the fixing shaft; the two-gear shifting rod can be rotatably fixed on the same fixed shaft.

The invention is provided with two groups of gear shifting driving mechanisms which do not influence each other, so as to be suitable for a three-gear or four-gear gearbox. The two positioning shafts are coaxial, the end part of one positioning shaft extends into a groove formed by the concave part of the other positioning shaft, when the shift lever touches the shift fork, the reaction force transmitted to the shift lever by the shift fork is transmitted to the other shift lever and a corresponding structure through the matching of the concave part and the convex part, so that the force transmitted by the shift fork is dispersed to each part, the stress of the part corresponding to the shift lever in contact with the shift fork is smaller, the possibility of shaking and gear punching is smaller, the structural stability of the gear-shifting mechanism is maintained, and the service life of the gear-shifting mechanism is prolonged. The fixing parts of the shift blocking rods are in contact with each other, so that the position of the other shift blocking rod is limited through the shift blocking rods, and the axial position of the shift blocking rods along the fixed shaft is limited without adopting other parts such as clamp springs and the like, so that the structure of the invention is more compact. The abdicating groove is used for reducing the contact area between the two shift levers and storing oil, so that the contact friction between the two shift levers is smaller. The two shifting rods are sleeved on the same fixed shaft, so that the assembly of the invention is convenient, the structure of the invention is simpler, the force transmission effect of the shifting rods after being stressed is better, and the use stability is better.

The invention has the advantages of large transmission torque, effective gear shifting, gear buffering and damping in the gear box, prolonged service life of the gear box and ensured normal use of the gear box.

Drawings

FIG. 1 is a schematic structural diagram of embodiment 1 of the present invention;

FIG. 2 is a sectional view of example 1 of the present invention;

fig. 3 is a schematic structural diagram of a shift lever according to embodiment 1 of the present invention;

fig. 4 is a schematic structural view of a link block of a swing link and a shift block lever according to embodiment 1 of the present invention;

FIG. 5 is a schematic structural diagram of embodiment 2 of the present invention

Fig. 6 is a schematic structural diagram of a shift lever according to embodiment 2 of the present invention

FIG. 7 is a schematic view of the positioning shaft of FIG. 5 showing a structure at the convex and concave portions

FIG. 8 is a schematic view of a transmission member according to embodiment 3 of the present invention;

FIG. 9 is a schematic structural view of the first transmission member according to embodiment 3;

FIG. 10 is a schematic structural view of the second transmission member according to embodiment 3;

FIG. 11 is a schematic view showing a structure of an elastic buffer block according to embodiment 3;

FIG. 12 is a schematic structural view of the elastic buffer block of embodiment 3 engaged with the second transmission member.

Detailed Description

The invention is further described below with reference to the figures and specific embodiments.

As shown in fig. 1 to 4, the rocker arm type gear shifting driving mechanism for the AMT gearbox of the electric vehicle of the invention comprises a driving motor 1, a driving member 2 for receiving the torque of the driving motor 1, a shift lever blocking linkage block 3, a fixed shaft 4 and a shift lever blocking 5, wherein the driving member 2 drives the shift lever blocking linkage block 3 to rotate around an automatic rotation axis under the action of the driving motor 1, the shift lever blocking linkage block 3 deviates from the automatic rotation axis, the axis of the fixed shaft 4 is parallel to the automatic rotation axis, one end of the shift lever blocking 5 is rotatably fixed with the fixed shaft 4, the other end of the shift lever blocking 5 extends to the side far away from the fixed shaft 4, a strip-shaped hole 51 is formed in the position of the shift lever blocking 5 deviating from the fixed shaft 4, one end of the shift lever blocking linkage block 3 extends into the strip-shaped hole 51, and the other end of the shift lever blocking. Wherein, the output shaft of the driving motor 1 is provided with a starting gear 11, and the transmission piece 2 is provided with a tooth structure 20 meshed with the starting gear 1. Wherein, the rotation axis is relatively positioned between the fixed shaft 4 and the strip-shaped hole 51.

The transmission piece 2 is provided with a positioning shaft 6 and a swing rod 7, the positioning shaft 6 is coaxial with the rotation axis, one end of the swing rod 7 is fixed with the positioning shaft 6, and the other end of the swing rod 7 extends to the side far away from the transmission piece and the positioning shaft and is rotatably fixed with the shifting rod blocking linkage block 3. The outer edge of the cross section of the end part of the deflector rod linkage block 3 in the strip-shaped hole 51 is arranged in a circular shape, and the strip-shaped hole 51 is in a waist-shaped hole structure with two arc-shaped ends.

Example 2

As shown in fig. 5 to 7, the present embodiment is applied to a three-gear or four-gear transmission case, and the transmission case of the present embodiment has two shift drive mechanisms. The driving motor 1 is fixed with the shell 100, the shell 100 is provided with two transmission parts 2, the two transmission parts 2 are respectively linked with a shift lever 5, the two transmission parts 2 are respectively provided with a positioning shaft 6, the two positioning shafts 6 are coaxially arranged, and the two shift levers 5 can be rotatably fixed on the same fixed shaft 4. The two-gear shift lever 5 is provided with an arc-shaped matching groove 52, the arc-shaped opening of the matching groove 52 faces the fixed shaft 4, and one end of the positioning shaft 6, which is far away from the transmission piece 2, is matched in the matching groove 52. Wherein the positioning shaft 6 is fixed in the housing by a bearing 60.

The adjacent end parts of the two positioning shafts 6 are provided with a concave part 61 and a convex part 62 which are matched with each other, the convex part 62 extends into the concave part 61, and the groove wall formed by the concave part 62 is in clearance fit with the outer surface of the convex part 61. Two keep off driving lever 5 including being used for the cover to establish the fixed part 501 outside fixed axle 4 and being equipped with the stirring portion 502 of bar hole 51, the fixed part 501 of two driving lever 5 pastes mutually, is formed with the groove 53 of stepping down that corresponds relatively and communicate on the terminal surface that two fixed parts 501 are close to each other, is equipped with lubricating oil in the groove 53 of stepping down, and the groove 53 of stepping down is the annular and centers on the fixed axle 4 circumference outside. The fixing portion 501 is provided with a guiding groove 54 to connect the receding groove 53 with the space in the housing 100.

Example 3

As shown in fig. 8 to 12, the transmission element 2 is composed of a first transmission element 21 and a second transmission element 22, the gearshift lever linkage block 3 is fixed to the first transmission element 21 via the positioning shaft 6 and the rocker lever 7, and the second transmission element 22 is configured to engage with the starting gear 11 to receive the torque of the drive motor 1. Wherein, the second transmission member 22 rotates to push the first transmission member 21 to rotate through the elastic buffer block 23.

Be provided with the linkage space between first driving medium 21 and the second driving medium 22, be equipped with the first convex body 221 that a plurality of interval set up in the linkage space, still be equipped with elastic buffer block 23 in the linkage space, elastic buffer block 23 has buffer block ring portion 231 and is the even interval setting of annular buffer portion 232 in the buffer block ring portion 231 outside, and a plurality of buffer portions 232 can cooperate between the adjacent first convex body 221 in linkage space.

The first protrusions 221 are fixed to the second transmission member 22, the second transmission member 22 is formed with an accommodating groove 220 for accommodating the elastic buffer block 23 and an outer limiting portion 222, and the first protrusions 221 are annularly and uniformly arranged on an inner wall of the outer limiting portion 222 (and an inner wall of the accommodating groove 220) at intervals.

The first transmission member 21 and the second transmission member 22 are sleeved with each other, and the elastic buffer block 23 is sleeved between the first transmission member 21 and the second transmission member 23. The middle part of the first transmission member 21 is provided with an inner limiting part 211, the first transmission member 21 is provided with a plurality of second convex bodies 212 which are arranged at intervals in a ring shape by taking the inner limiting part 211 as a center, the elastic buffer block 23 is sleeved outside the circumference of the inner limiting part 212 and is positioned in the outer limiting part 222 of the second transmission member 22 (namely positioned in the accommodating groove 220), a first positioning groove 233 matched with the second convex body 212 is formed on the buffer part 232 of the elastic buffer block 23, and a second positioning groove 234 matched with the first convex body 221 is formed between two adjacent buffer parts 232.

The elastic buffer block 23, the first transmission member 21 and the second transmission member 22 are all provided with through holes 63 for the positioning shaft 6 to pass through, wherein the positioning shaft 6 is linked with the first transmission member 21 through key fitting, and the first transmission member 21 is provided with a key groove 213 matched with the key.

This example also differs from examples 1 and 2 in that: an arc-shaped groove 224 which gives way to the starting gear 11 is arranged at the position where the second transmission piece 22 deviates from the rotation axis, the circle center of the arc-shaped groove 224 is positioned on the rotation axis, and a tooth structure 20 which is used for being meshed with the starting gear 11 of the driving motor 1 is arranged on the groove wall of the arc-shaped groove 224 which deviates from the rotation axis.

The invention has the advantages of large transmission torque, effective gear shifting, gear buffering and damping in the gear box, prolonged service life of the gear box and ensured normal use of the gear box.