Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a double-clutch transmission and a double-clutch speed changing method, which can effectively solve the problems.
The technical scheme adopted by the invention is as follows:
the invention provides a 1, a double clutch transmission, characterized by, including: the gear shifting mechanism comprises a motor (1), an input shaft (2), an intermediate shaft (3), an output shaft (4), a first-gear clutch assembly, a second-gear clutch assembly, a first-gear driving gear (5), a first-gear driven gear (6), a second-gear driving gear (7), a second-gear driven gear (8), a main reducer driving gear (9), a main reducer driven gear (10), a differential mechanism assembly (11), a clutch sleeve (12) and a gear shifting pull rod (13);
the output end of the motor (1) is linked with the input shaft (2); the input shaft (2), the intermediate shaft (3) and the output shaft (4) are arranged in parallel;
one end of the input shaft (2) is provided with an axial hole (A); a radial hole (B) communicated with the axial hole (A) is formed in the axial center of the input shaft (2); the gear shifting pull rod (13) is of a T-shaped structure, one end of the gear shifting pull rod (13) is located outside the input shaft (2), the other end of the gear shifting pull rod (13) penetrates into the axial hole (A), and a vertical rod (13-1) at the other end of the gear shifting pull rod (13) extends outwards from the radial hole (B); the clutch sleeve (12) can be sleeved outside the input shaft (2) in an axially sliding manner, and the clutch sleeve (12) is fixed with a vertical rod (13-1) of the gear shifting pull rod (13); when the gear shifting pull rod (13) moves along the axial direction, the clutch sleeve (12) is driven to move axially in the range of the radial hole (B);
the surface of the clutch sleeve (12) forms a left inclined surface (12-1) and a right inclined surface (12-2); the left end of the left inclined plane (12-1) is lower than the right end; the right end of the right inclined plane (12-2) is lower than the left end;
the first-gear clutch assembly is arranged on the right side of the clutch sleeve (12) and comprises a first-gear clutch shifting fork (14), a first-gear clutch driving disc (15) and a first-gear clutch driven disc (16); the driving disc (15) of the first-gear clutch is rigidly sleeved outside the input shaft (2), and the driven disc (16) of the first-gear clutch is nested on the right side of the driving disc (15) of the first-gear clutch; the first-gear clutch shifting fork (14) comprises a first shifting fork main body (14-1), a first roller (14-2) and a first connecting rod (14-3); the first shifting fork main body (14-1) is of an L-shaped structure, and the bent position of the first shifting fork main body (14-1) is hinged with the driving disc (15) of the first-gear clutch; one end of the first fork main body (14-1) is provided with the first roller (14-2), and the first roller (14-2) is in contact with the right inclined surface (12-2); the other end of the first shifting fork main body (14-1) is fixed with one end of the first connecting rod (14-3); the other end of the first connecting rod (14-3) penetrates through a first-gear clutch driving disc (15) and a first-gear clutch driven disc (16) and extends to the outside; when the first connecting rod (14-3) moves axially, the first-gear clutch driving disc (15) and the first-gear clutch driven disc (16) are driven to be engaged or disengaged;
the second-gear clutch assembly is arranged on the left side of the clutch sleeve (12) and is in a symmetrical structure with the first-gear clutch assembly, and the second-gear clutch assembly comprises a second-gear clutch shifting fork (17), a second-gear clutch driving disc (18) and a second-gear clutch driven disc (19); the second-gear clutch shifting fork (17) comprises a second shifting fork main body (17-1), a second roller (17-2) and a second connecting rod (17-3); wherein the second roller (17-2) is in contact with the left bevel (12-1);
the first-gear driving gear (5) is sleeved outside the input shaft (2) in a sliding mode and is rigidly connected with the first-gear clutch driven disc (16);
the second-gear driving gear (7) is sleeved outside the input shaft (2) in a sliding manner and is rigidly connected with the second-gear clutch driven disc (19);
the first-gear driven gear (6) is rigidly sleeved outside the intermediate shaft (3) and is meshed with the first-gear driving gear (5);
the second-gear driven gear (8) is rigidly sleeved outside the intermediate shaft (3) and is meshed with the second-gear driving gear (7);
the driving gear (9) of the main speed reducer is rigidly sleeved outside the intermediate shaft (3); the driven gear (10) of the main speed reducer is rigidly sleeved outside the output shaft (4) and is meshed with the driving gear (9) of the main speed reducer; the differential assembly (11) is rigidly sleeved outside the output shaft (4).
Preferably, the diameter of the first gear driving gear (5) is smaller than that of the second gear driving gear (7); the diameter of the first-gear driven gear (6) is larger than that of the second-gear driven gear (8).
Preferably, the gear ratio of the first-gear driven gear (6) to the first-gear driving gear (5) is a first transmission ratio; the gear ratio of the second-gear driven gear (8) to the second-gear driving gear (7) is a second transmission ratio; the first gear ratio is greater than the second gear ratio.
Preferably, the number of the first-gear clutch shifting forks (14) is three; the number of the second-gear clutch shifting forks (17) is three.
The invention also provides a double-clutch speed changing method based on the double-clutch gearbox, which comprises the following steps:
step 1, assuming that the current gearbox is in a second gear state, the working process is as follows:
step 1.1, when the gearbox is in a second gear state, the clutch sleeve (12) slides to a left limit position under the action of the gear shifting pull rod (13), at the moment, a second roller (17-2) of a second gear clutch shifting fork (17) is located at the highest point position of a left inclined plane (12-1) of the clutch sleeve (12), and at the moment, under the action of the second gear clutch shifting fork (17), a driving disc (18) and a driven disc (19) of a second gear clutch are in an engaged state;
meanwhile, a first roller (14-2) of the first-gear clutch shifting fork (14) is positioned at the lowest point of a right inclined plane (12-2) of the clutch sleeve (12), and at the moment, under the action of the first-gear clutch shifting fork (14), a driving disc (15) and a driven disc (16) of the first-gear clutch are in a disconnected state;
step 1.2, a motor (1) drives an input shaft (2) to rotate, and because a first-gear clutch driving disc (15) and a second-gear clutch driving disc (18) are both rigidly connected with the input shaft (2), the input shaft (2) drives the first-gear clutch driving disc (15) and the second-gear clutch driving disc (18) to rotate simultaneously, and the power of the input shaft (2) is respectively transmitted to the first-gear clutch driving disc (15) and the second-gear clutch driving disc (18);
step 1.3, as the driving disc (15) of the first-gear clutch and the driven disc (16) of the first-gear clutch are in a disconnected state, power is transmitted to the driving disc (15) of the first-gear clutch and then is stopped;
because the driving disc (18) of the second-gear clutch and the driven disc (19) of the second-gear clutch are in an engaged state, and the driving gear (7) of the second-gear clutch is rigidly connected with the driven disc (19) of the second-gear clutch, when the input shaft (2) rotates, the driving gear (7) of the second-gear clutch is driven to synchronously rotate through the driving disc (18) of the engaged second-gear clutch and the driven disc (19) of the second-gear clutch, and power is transmitted to the driving gear (7) of the second-gear clutch after passing through the driving disc (18) of the engaged second-gear clutch and the driven disc (19) of the second-gear clutch;
step 1.4, as the second-gear driving gear (7) is meshed with the second-gear driven gear (8), the second-gear driving gear (7) drives the second-gear driven gear (8) to rotate when rotating, and power is transmitted to the second-gear driven gear (8) through the second-gear driving gear (7);
step 1.5, because the second-gear driven gear (8) is rigidly connected with the intermediate shaft (3), the second-gear driven gear (8) drives the intermediate shaft (3) to rotate, and power is transmitted to the intermediate shaft (3) through the second-gear driven gear (8);
step 1.6, as the driving gear (9) of the main speed reducer and the first-gear driven gear (6) are both rigidly connected with the intermediate shaft (3), when the intermediate shaft (3) rotates, the driving gear (9) of the main speed reducer and the first-gear driven gear (6) are driven to synchronously rotate, and power is simultaneously transmitted to the driving gear (9) of the main speed reducer and the first-gear driven gear (6) from the intermediate shaft (3);
step 1.7, for the first-gear driven gear (6), the first-gear driven gear is meshed with the first-gear driving gear (5), but the first-gear driving gear (5) does not have power input, so that the first-gear driving gear (5) rotates along with the first-gear driven gear (6); because the first-gear driving gear (5) is rigidly connected with the first-gear clutch driven disc (16), the first-gear driving gear (5) drives the first-gear clutch driven disc (16) to synchronously rotate, but because the first-gear clutch driven disc (16) and the first-gear clutch driving disc (15) are in a disconnected state, a rotating speed difference is formed between the first-gear clutch driven disc (16) and the first-gear clutch driving disc (15), and the power is transmitted to the first-gear clutch driven disc (16) and is stopped;
for the main reducer driving gear (9), the main reducer driving gear (9) is meshed with the main reducer driven gear (10), so that the main reducer driving gear (9) drives the main reducer driven gear (10) to rotate, and power is transmitted to the main reducer driven gear (10) from the main reducer driving gear (9);
because the main reducer driven gear (10) is rigidly connected with the output shaft (4), the main reducer driven gear (10) drives the output shaft (4) to rotate, and power is transmitted to the output shaft (4) from the main reducer driven gear (10);
because the differential assembly (11) is rigidly connected with the output shaft (4), the final power is transmitted to the differential assembly (11) from the output shaft (4), and the second-gear working state is realized;
step 2, when the gear needs to be shifted from the second gear state to the first gear state, the following method is adopted:
step 2.1, under the condition that the motor (1) continuously works, a gear shifting pull rod (13) is pulled rightwards, and the gear shifting pull rod (13) pulls a clutch sleeve (12) from a left limit position to a right limit position;
2.2, in the movement process of the clutch sleeve (12) from the left limit position to the right limit position, a second roller (17-2) of the second-gear clutch shifting fork (17) slides from the highest point position to the lowest point position along a left inclined plane (12-1) of the clutch sleeve (12), so that a second shifting fork main body (17-1) rotates, a second connecting rod (17-3) is driven to move, a second-gear clutch driving disc (18) and a second-gear clutch driven disc (19) are gradually disconnected, and the second-gear power transmission is gradually reduced;
meanwhile, a first roller (14-2) of a first-gear clutch shifting fork (14) slides to a highest point position from a lowest point position along a right inclined plane (12-2) of a clutch sleeve (12), at the moment, under the action of the first-gear clutch shifting fork (14), a first-gear clutch driving disc (15) and a first-gear clutch driven disc (16) are gradually engaged, and first-gear power transmission is gradually increased;
and 2.3, driving the input shaft (2) to rotate by the motor (1), sequentially passing the force through the input shaft (2), the first-gear clutch driving disc (15) and the first-gear clutch driven disc (16) in a meshed state, the first-gear driving gear (5), the first-gear driven gear (6), the intermediate shaft (3), the main reducer driving gear (9), the main reducer driven gear (10) and the output shaft (4), and transmitting the force to the differential assembly (11) to realize a gear shifting process.
The double-clutch gearbox and the double-clutch speed changing method provided by the invention have the following advantages that:
1. the gear shifting is simple, and the gear shifting can be realized only by operating the gear shifting pull rod during the gear shifting;
2. the power is not interrupted when the gear is shifted, the motor continuously works, and the gear shifting is stable and has no impact.
3. The double clutch has high efficiency and long service life.
4. The size is small, the weight is light, and the arrangement is facilitated.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The invention provides a double-clutch gearbox and a double-clutch speed change method, which can realize multi-gear shifting of an electric automobile, and the power is not interrupted during shifting, and the shifting is stable and has no impact, so as to meet different requirements of the automobile on speed and torque under different road conditions or load conditions.
The invention provides a double-clutch gearbox, which is characterized in that a first-gear clutch assembly and a second-gear clutch assembly are oppositely arranged, when the first-gear clutch assembly is combined, the second-gear clutch assembly is separated, otherwise, when the first-gear clutch assembly is separated, the second-gear clutch assembly is combined. When the clutch device works, the clutch sleeve 12 is pulled by pulling the gear shifting pull rod 13, so that the separation and combination of the first-gear clutch assembly and the second-gear clutch assembly are controlled, and the gear switching of the first gear and the second gear is realized.
Referring to fig. 1, a dual clutch transmission comprising: the device comprises a motor 1, an input shaft 2, an intermediate shaft 3, an output shaft 4, a first-gear clutch assembly, a second-gear clutch assembly, a first-gear driving gear 5, a first-gear driven gear 6, a second-gear driving gear 7, a second-gear driven gear 8, a main reducer driving gear 9, a main reducer driven gear 10, a differential assembly 11, a clutch sleeve 12 and a gear shifting pull rod 13;
the output end of the motor 1 is linked with the input shaft 2; the input shaft 2, the intermediate shaft 3 and the output shaft 4 are arranged in parallel;
referring to fig. 3, one end of the input shaft 2 is provided with an axial hole a; a radial hole B communicated with the axial hole A is formed in the axial center of the input shaft 2; the gear shifting pull rod 13 is of a T-shaped structure, one end of the gear shifting pull rod 13 is positioned outside the input shaft 2, the other end of the gear shifting pull rod 13 penetrates into the axial hole A, and a vertical rod 13-1 at the other end of the gear shifting pull rod 13 extends out of the radial hole B; the clutch sleeve 12 can be sleeved outside the input shaft 2 in an axially sliding manner, and the clutch sleeve 12 is fixed with a vertical rod 13-1 of the gear shifting pull rod 13; when the gear shifting pull rod 13 moves along the axial direction, the clutch sleeve 12 is driven to move axially in the range of the radial hole B;
referring to fig. 2, the surfaces of the clutch sleeve 12 form a left bevel 12-1 and a right bevel 12-2; the left end of the left inclined plane 12-1 is lower than the right end; the right end of the right inclined plane 12-2 is lower than the left end;
referring to fig. 4 to 5, a first-gear clutch assembly is disposed at the right side of the clutch sleeve 12, and the first-gear clutch assembly includes a first-gear clutch fork 14, a first-gear clutch driving plate 15, and a first-gear clutch driven plate 16; a first-gear clutch driving disc 15 is rigidly sleeved outside the input shaft 2, and a first-gear clutch driven disc 16 is nested on the right side of the first-gear clutch driving disc 15; the first-gear clutch fork 14 comprises a first fork main body 14-1, a first roller 14-2 and a first connecting rod 14-3; the first shifting fork main body 14-1 is of an L-shaped structure, and the bent position of the first shifting fork main body 14-1 is hinged with a first-gear clutch driving disc 15; one end of the first fork main body 14-1 is provided with a first roller 14-2, and the first roller 14-2 is in contact with the right inclined surface 12-2; the other end of the first fork main body 14-1 is fixed with one end of a first connecting rod 14-3; the other end of the first link 14-3 extends to the outside through the first-gear clutch driving disk 15 and the first-gear clutch driven disk 16; when the first connecting rod 14-3 moves axially, the first-gear clutch driving disc 15 and the first-gear clutch driven disc 16 are driven to be engaged or disengaged;
the second gear clutch assembly is arranged on the left side of the clutch sleeve 12 and is in a symmetrical structure with the first gear clutch assembly, and the second gear clutch assembly comprises a second gear clutch shifting fork 17, a second gear clutch driving disc 18 and a second gear clutch driven disc 19; the second-gear clutch shift fork 17 comprises a second shift fork main body 17-1, a second roller 17-2 and a second connecting rod 17-3; wherein, the second roller 17-2 is contacted with the left inclined plane 12-1;
the first gear driving gear 5 is sleeved outside the input shaft 2 in a sliding mode and is rigidly connected with a first gear clutch driven disc 16;
the second gear driving gear 7 is sleeved outside the input shaft 2 in a sliding manner and is rigidly connected with a second gear clutch driven disc 19;
the first-gear driven gear 6 is rigidly sleeved outside the intermediate shaft 3 and is meshed with the first-gear driving gear 5;
the second-gear driven gear 8 is rigidly sleeved outside the intermediate shaft 3 and is meshed with the second-gear driving gear 7;
a driving gear 9 of the main reducer is rigidly sleeved outside the intermediate shaft 3; a driven gear 10 of the main speed reducer is rigidly sleeved outside the output shaft 4 and is meshed with a driving gear 9 of the main speed reducer; the differential assembly 11 is rigidly sleeved outside the output shaft 4.
In order to realize the stability of the gear shifting process, the number of the first-gear clutch shifting forks 14 is three; the number of the second-gear clutch forks 17 is three. Are all evenly distributed along the circumference.
Wherein, the diameter of the first gear driving gear 5 is smaller than that of the second gear driving gear 7; the diameter of the first-gear driven gear 6 is larger than that of the second-gear driven gear 8.
The gear ratio of the first-gear driven gear 6 to the first-gear driving gear 5 is a first transmission ratio; the gear ratio of the second-gear driven gear 8 to the second-gear driving gear 7 is a second transmission ratio; the first gear ratio is greater than the second gear ratio. Therefore, the speed change effect that the first gear is a low-speed gear and the second gear is a high-speed gear is realized.
The invention also provides a double-clutch speed changing method based on the double-clutch gearbox, which comprises the following steps:
step 1, assuming that the current gearbox is in a second gear state, the working process is as follows:
step 1.1, when the gearbox is in a second gear state, the clutch sleeve 12 slides to a left limit position under the action of the gear shifting pull rod 13, at the moment, a second roller 17-2 of a second gear clutch shifting fork 17 is positioned at the highest point of a left inclined plane 12-1 of the clutch sleeve 12, and at the moment, under the action of the second gear clutch shifting fork 17, a driving disc 18 and a driven disc 19 of a second gear clutch are in an engaged state;
meanwhile, the first roller 14-2 of the first-gear clutch shifting fork 14 is positioned at the lowest point of the right inclined plane 12-2 of the clutch sleeve 12, and at the moment, under the action of the first-gear clutch shifting fork 14, the driving disc 15 of the first-gear clutch and the driven disc 16 of the first-gear clutch are in a disconnected state;
step 1.2, the motor 1 drives the input shaft 2 to rotate, and because the first-gear clutch driving disc 15 and the second-gear clutch driving disc 18 are both rigidly connected with the input shaft 2, the input shaft 2 drives the first-gear clutch driving disc 15 and the second-gear clutch driving disc 18 to rotate simultaneously, and the power of the input shaft 2 is respectively transmitted to the first-gear clutch driving disc 15 and the second-gear clutch driving disc 18;
step 1.3, because the driving disk 15 of the first-gear clutch and the driven disk 16 of the first-gear clutch are in a disconnected state, power is transmitted to the driving disk 15 of the first-gear clutch and then is stopped;
because the driving disk 18 and the driven disk 19 of the second gear clutch are in an engaged state, and the driving disk 7 of the second gear clutch is rigidly connected with the driven disk 19 of the second gear clutch, when the input shaft 2 rotates, the driving disk 18 of the second gear clutch and the driven disk 19 of the second gear clutch which are engaged drive the driving disk 7 of the second gear to synchronously rotate, and power is transmitted to the driving disk 7 of the second gear clutch after passing through the driving disk 18 of the second gear clutch and the driven disk 19 of the second gear clutch which are engaged;
step 1.4, as the second-gear driving gear 7 is meshed with the second-gear driven gear 8, the second-gear driving gear 7 drives the second-gear driven gear 8 to rotate when rotating, and power is transmitted to the second-gear driven gear 8 through the second-gear driving gear 7;
step 1.5, because the second-gear driven gear 8 is rigidly connected with the intermediate shaft 3, the second-gear driven gear 8 drives the intermediate shaft 3 to rotate, and power is transmitted to the intermediate shaft 3 from the second-gear driven gear 8;
step 1.6, as the driving gear 9 of the main reducer and the first-gear driven gear 6 are both rigidly connected with the intermediate shaft 3, when the intermediate shaft 3 rotates, the driving gear 9 of the main reducer and the first-gear driven gear 6 are driven to synchronously rotate, and power is simultaneously transmitted to the driving gear 9 of the main reducer and the first-gear driven gear 6 from the intermediate shaft 3;
step 1.7, for the first-gear driven gear 6, the first-gear driven gear is meshed with the first-gear driving gear 5, but the first-gear driving gear 5 does not have power input, so that the first-gear driving gear 5 rotates along with the first-gear driven gear 6; since the first-gear driving gear 5 is rigidly connected with the first-gear clutch driven disc 16, the first-gear driving gear 5 drives the first-gear clutch driven disc 16 to rotate synchronously, but since the first-gear clutch driven disc 16 and the first-gear clutch driving disc 15 are in a disconnected state, a rotation speed difference is formed between the first-gear clutch driven disc 16 and the first-gear clutch driving disc 15, and power is transmitted to the first-gear clutch driven disc 16;
for the main reducer driving gear 9, because the main reducer driving gear 9 is meshed with the main reducer driven gear 10, the main reducer driving gear 9 drives the main reducer driven gear 10 to rotate, and power is transmitted to the main reducer driven gear 10 from the main reducer driving gear 9;
because the main reducer driven gear 10 is rigidly connected with the output shaft 4, the main reducer driven gear 10 drives the output shaft 4 to rotate, and power is transmitted from the main reducer driven gear 10 to the output shaft 4;
because the differential assembly 11 is rigidly connected with the output shaft 4, the final power is transmitted from the output shaft 4 to the differential assembly 11, and the second-gear working state is realized;
step 2, when the gear needs to be shifted from the second gear state to the first gear state, the following method is adopted:
step 2.1, under the condition that the motor 1 continuously works, the gear shifting pull rod 13 is pulled rightwards, and the gear shifting pull rod 13 pulls the clutch sleeve 12 from the left limit position to the right limit position;
2.2, in the process of moving the clutch sleeve 12 from the left limit position to the right limit position, sliding a second roller 17-2 of the second-gear clutch shifting fork 17 from the highest point position to the lowest point position along a left inclined plane 12-1 of the clutch sleeve 12, so that a second shifting fork main body 17-1 rotates, further driving a second connecting rod 17-3 to move, gradually disconnecting a second-gear clutch driving disc 18 and a second-gear clutch driven disc 19, and gradually reducing second-gear power transmission;
meanwhile, the first roller 14-2 of the first-gear clutch fork 14 slides from the lowest point position to the highest point position along the right inclined plane 12-2 of the clutch sleeve 12, at the moment, under the action of the first-gear clutch fork 14, the driving disc 15 of the first-gear clutch and the driven disc 16 of the first-gear clutch are gradually engaged, and the power transmission of the first gear is gradually increased;
and 2.3, driving the input shaft 2 to rotate by the motor 1, and transmitting the force to the differential assembly 11 after sequentially passing through the input shaft 2, the first-gear clutch driving disc 15 and the first-gear clutch driven disc 16 in an engaged state, the first-gear driving gear 5, the first-gear driven gear 6, the intermediate shaft 3, the main reducer driving gear 9, the main reducer driven gear 10 and the output shaft 4, so as to realize a gear shifting process.
The working principle can be described roughly as follows:
fig. 1 shows the first-gear state, in which the clutch sleeve 12 is in a position close to the first-gear clutch, the first-gear clutch fork 14 is pressed outward by the clutch sleeve 12, and the first-gear clutch driven plate 16 is engaged with the first-gear clutch driving plate 15. The second-gear clutch fork 17 is in a contracted state, and the second-gear clutch driven disc 19 is disconnected from the second-gear clutch driving disc 18.
At this time, the first-gear driving gear 5 drives the first-gear driven gear 6 to rotate, thereby driving the intermediate shaft and the output shaft to rotate. At this time, the second-gear driving gear 7 does not have power input and rotates with the second-gear driven gear 8, and simultaneously drives the second-gear clutch driven disc 19, and the second-gear clutch driven disc 19 and the second-gear clutch driving disc 18 form a rotation speed difference.
When the first gear is switched to the second gear, the gear shifting pull rod 13 is pushed leftwards, the clutch sleeve 12 moves towards the second gear clutch, the first gear clutch is gradually disconnected in the moving process, the first gear power transmission is gradually reduced, the second gear clutch is gradually engaged, and the second gear power transmission is gradually increased from 0. When the gear is switched, the power speed is switched stably without impact. When the shift rod 13 moves to a specified position, the power transmission of the first gear is completely disconnected. At this time, the second-gear driving gear 7 drives the second-gear driven gear 8 to rotate, thereby driving the intermediate shaft and the output shaft to rotate. At this time, the first-gear driving gear 5 does not have power input and rotates with the first-gear driven gear 6, and simultaneously drives the first-gear clutch driven disc 16, and the first-gear clutch driven disc 16 and the first-gear clutch driving disc 15 form a rotation speed difference.
The invention provides a double-clutch gearbox and a double-clutch speed changing method, which have the following advantages:
1. the gear shifting is simple, and the gear shifting can be realized only by operating the gear shifting pull rod during the gear shifting;
2. the power is not interrupted when the gear is shifted, the motor continuously works, and the gear shifting is stable and has no impact.
3. The double clutch has high efficiency and long service life.
4. The size is small, the weight is light, and the arrangement is facilitated.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and improvements can be made without departing from the principle of the present invention, and such modifications and improvements should also be considered within the scope of the present invention.