Three-planet row continuously variable transmission mechanism with stepped input and its shifting method

Abstract

The application discloses a three-planet-row stepless speed change mechanism with step input and a speed change method thereof, and belongs to the technical field of stepless speed changers. The three-planet-row stepless speed change mechanism comprises a first planet row, a second planet row, a third planet row and a transmission stage. The transmission stage comprises a transmission gear A and a transmission gear B. The transmission gear A and the transmission gear B are engaged through external teeth. A first gear ring on the first planet row is connected with a second planet carrier on the second planet row. The second planet carrier on the second planet row is connected with a third sun gear on the third planet row through a connecting shaft. A first planet carrier on the first planet row is connected with a second gear ring on the second planet row and a third gear ring on the third planet row. The transmission stage is arranged between a first input shaft and a transmission shaft of the three-planet-row stepless speed change mechanism. By changing the tooth ratio of the transmission gear A and the transmission gear B, the transmission ratio between a first driving member and the first sun gear is changed, and the power selection range of the first driving member is widened.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of continuously variable transmission, in particular to a three-planet-row continuously variable transmission mechanism with step input and a transmission method thereof. BACKGROUND

[0002] With the increasing demand for environmental protection, electric vehicle technology has become the mainstream research direction of major car companies. At present, electric vehicles mostly use fixed speed ratio reducers. Although a reducer with a large speed ratio can meet the power demand of the vehicle when starting and climbing, the large speed ratio limits the vehicle from reaching a high maximum speed, which is also the reason why the maximum speed of electric vehicles on the market is generally lower than that of fuel vehicles. In order to balance the maximum speed and climbing ability of the vehicle, many car companies have begun to install AMT transmissions on electric vehicles. However, AMT transmissions are inherently step-variable, which has the problems of gear shifting jerk and power interruption. The transmission ratio range of AMT transmissions is limited by the gear setting. When applied to heavy vehicles, a large number of gears need to be set in order to expand the transmission ratio range, which results in a slow gear shifting process and complex operation, making many heavy vehicle drivers reluctant to step on the brake. The gear shifting process of AMT transmissions relies on complex control strategies, making it difficult to grasp the accurate gear shifting timing, resulting in high energy consumption and low efficiency. The structure of AMT transmissions is complex, the manufacturing cost is high, and the maintenance is difficult. SUMMARY

[0003] The present application aims to solve the above problems and provides a three-planet-row continuously variable transmission mechanism with step input and a transmission method thereof.

[0004] To achieve the above-mentioned purpose, the present application provides a three-planet-row continuously variable transmission mechanism with step input, which comprises a first planetary row, a second planetary row, a third planetary row and a transmission stage. The transmission stage comprises a transmission gear A and a transmission gear B. The transmission gear A and the transmission gear B are engaged by external teeth. A first ring gear on the first planetary row is connected to a second carrier on the second planetary row. The second carrier is connected to a third sun gear on the third planetary row through a connecting shaft. A first carrier on the first planetary row is connected to a second ring gear on the second planetary row and a third ring gear on the third planetary row. A one-way stopper is arranged on the connecting body of the first carrier, the second ring gear and the third ring gear. A third carrier on the third planetary row is connected to an output component. A first sun gear on the first planetary row is connected to the transmission gear B through a transmission shaft. A second input shaft connected to a second sun gear on the second planetary row passes through the first sun gear, the transmission shaft and the transmission gear B and is connected to a second driving member. The transmission gear A on the transmission stage is connected to a first driving member through a first input shaft.

[0005] As a further explanation of the present application, the outer teeth of the first sun gear mesh with first planetary gears, the first planetary gears are mounted on the first planetary carrier, the first planetary gears mesh with the inner ring teeth of the first ring gear;

[0006] The outer teeth of the second sun gear mesh with second planetary gears, the second planetary gears are mounted on the second planetary carrier, the second planetary gears mesh with the inner ring teeth of the second ring gear;

[0007] The outer teeth of the third sun gear mesh with third planetary gears, the third planetary gears are mounted on the third planetary carrier, the third planetary gears mesh with the inner ring teeth of the third ring gear.

[0008] As a further explanation of the present application, the one-way stopper is used to limit the rotation direction of the first planetary carrier, the second ring gear and the third ring gear, the one-way stopper makes the rotation direction of the first planetary carrier, the second ring gear and the third ring gear consistent with the rotation direction of the second driving member only.

[0009] The present application also provides a speed changing method of the three planetary row stepless speed changing mechanism based on hierarchical input, the second driving member and the second sun gear are connected through the second input shaft, so that the rotation speed of the second driving member is the same as the rotation speed of the second sun gear; the first driving member and the first sun gear are connected through the first input shaft, the transmission stage and the transmission shaft, so that the rotation speed of the first driving member is proportional to the rotation speed of the first sun gear according to the transmission ratio of the transmission stage; the first planetary carrier, the second ring gear and the third ring gear are connected, so that the rotation speed of the first planetary carrier, the second ring gear and the third ring gear is the same; the first ring gear, the second planetary carrier and the third sun gear are connected, so that the rotation speed of the first ring gear, the second planetary carrier and the third sun gear is the same; the output member is connected with the third planetary carrier, so that the rotation speed of the third planetary carrier and the output member is the same; by adjusting and controlling the rotation speed of the first driving member and the rotation speed of the second driving member, the stepless continuous change of the rotation speed of the output member is realized, and in this process, the speed ratio also changes accordingly.

[0010] As a further illustration of the application, it is provided that the rotational speed of the second driving member and the rotational speed of the second sun gear is N2, the rotational speed of the first sun gear is N1, the transmission ratio of the transmission stage is i, the rotational speed of the first driving member is N1x i, the rotational speed of the first ring gear, the second carrier and the third sun gear is N3, the rotational speed of the first carrier, the second ring gear and the third ring gear is N4, the rotational speed of the third carrier and the output component is N5, the number of teeth of the first sun gear is Z1, the number of teeth of the first ring gear is Z2, the number of teeth of the second sun gear is Z3, the number of teeth of the second ring gear is Z4, the number of teeth of the third sun gear is Z5, the number of teeth of the third ring gear is Z6, when any two of the N1, N2, N3, N4 and N5 are determined, the other three values can be calculated by the proportional relationship of the line segments in the vector diagram; by adjusting and controlling the rotational speed N1 of the first sun gear and the rotational speed N2 of the second sun gear through driving the first driving member and the second driving member, the continuous stepless change of the rotational speed N5 of the output component can be realized; by adjusting and controlling the rotational speed N1 of the first sun gear and the rotational speed N2 of the second sun gear, the output state of the output component includes state A, state B, state C, state D and state E.

[0011] As a further illustration of the application, in the state A, the rotational speed of the first driving member driving the first sun gear is N1, the direction is reverse, the rotational speed of the second driving member driving the second sun gear is N2, the direction is forward, the ratio of the rotational speed N2 of the second sun gear and the rotational speed N1 of the first sun gear is equal to [Z1x (Z3+Z4)] / (Z2x Z3), the rotational speed N4 of the first carrier, the second ring gear and the third ring gear is 0, the direction of the rotational speed N5 of the output component is forward.

[0012] As a further illustration of the application, in the state B, the rotational speed of the first driving member driving the first sun gear is N1, the direction is reverse, the rotational speed of the second driving member driving the second sun gear is N2, the direction is forward, the ratio of the rotational speed N2 of the second sun gear and the rotational speed N1 of the first sun gear is greater than [Z1x (Z3+Z4)] / (Z2x Z3), the rotational speed N4 of the first carrier, the second ring gear and the third ring gear is forward, the direction of the rotational speed N5 of the output component is forward.

[0013] As a further illustration of the application, in the state C, the first driving member drives the first sun gear at a speed N1 in a reverse direction, the second driving member drives the second sun gear at a speed N2 in a forward direction, the ratio of the speed N2 of the second sun gear to the speed N1 of the first sun gear is less than [Z1×(Z3+Z4)] / (Z2×Z3), the speed N4 of the first carrier, the second ring gear and the third ring gear is in a reverse direction, and the speed N5 of the output member can be in a forward direction or a reverse direction. To prevent the speed N5 of the output member from being in a reverse direction, a one-way stopper is arranged on the connecting body of the first carrier, the second ring gear and the third ring gear to limit the speed N4 of the first carrier, the second ring gear and the third ring gear to be in a forward direction only. Thus, the speed N5 of the output member is always in a forward direction.

[0014] As a further illustration of the application, in the state D, the first driving member drives the first sun gear at a speed N1 of 0, the second driving member drives the second sun gear at a speed N2 in a forward direction, the speed N4 of the first carrier, the second ring gear and the third ring gear is in a forward direction, and the speed N5 of the output member is in a forward direction.

[0015] As a further illustration of the application, in the state E, the first driving member drives the first sun gear at a speed N1 and the second driving member drives the second sun gear at a speed N2, both of which are in a forward direction and have the same magnitude, the speed N4 of the first carrier, the second ring gear and the third ring gear is in a forward direction and has the same magnitude as the speed N1 and the speed N2, and the speed N5 of the output member is in a forward direction and has the same magnitude as the speed N1, the speed N2 and the speed N4. The transmission ratio of the state E is 1.

[0016] As a further illustration of the application, when the first driving member fails, the second driving member drives at a speed N2 in a reverse direction, the second sun gear drives at a speed N2 in a forward direction, the speed N4 of the first carrier, the second ring gear and the third ring gear has a reverse trend, and the one-way stopper limits the reverse trend of the speed N4 of the first carrier, the second ring gear and the third ring gear to be 0. The output member rotates in a forward direction at a speed N5. The power of the second driving member is transmitted through the second planetary gear set and the third planetary gear set to increase the torque and reduce the speed, and the transmission ratio is [(Z3+Z4)×(Z5+Z6)] / (Z3×Z5).

[0017] As a further illustration of the present application, when the second driving member fails, the first driving member drives the first sun gear at a speed of N1 in a reverse direction, and the first planetary carrier, the second ring gear and the third ring gear have a reverse rotation tendency, at which time the one-way clutch limits the reverse rotation to make the speed N4 of the first planetary carrier, the second ring gear and the third ring gear 0, and the output member rotates in a forward direction at a speed of N5, and the power of the first driving member is transmitted through the transmission system, the first planetary gear set and the third planetary gear set to be decelerated and increased in torque for output, and the transmission ratio is i x [Z2 x (Z5 + Z6)] / (Z1 x Z5).

[0018] The present application provides a three planetary gear set step input continuously variable transmission mechanism and a transmission method thereof, which changes the transmission ratio between the input end and the output end through the adjustment of the speed of the first driving member and the second driving member and the cooperation between the first planetary gear set, the second planetary gear set, the third planetary gear set and the one-way clutch, so as to realize the stepless transmission of the output end, and has the advantages of high transmission efficiency, large output torque, no power interruption, simple and reliable structure, low manufacturing cost, easy maintenance, simple and convenient speed adjustment and the like. In addition, the connection end of the first driving member and the second driving member is arranged on the same side of the continuously variable transmission mechanism, and the connection end of the output member is arranged on the other side of the continuously variable transmission mechanism, so that the positions of the input and the output can be better separated, the probability of mutual interference between the input end and the output member is reduced, and the space utilization can be greatly improved, so that the arrangement and space occupancy of the entire power equipment are more reasonable. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a schematic view of the three planetary gear set step input continuously variable transmission mechanism provided by the embodiment of the present application;

[0020] Figure 2 is a speed vector diagram of the first planetary gear set provided by the embodiment of the present application;

[0021] Figure 3 is a speed vector diagram of the second planetary gear set provided by the embodiment of the present application;

[0022] Figure 4 is a speed vector diagram of the third planetary gear set provided by the embodiment of the present application;

[0023] Figure 5 is a speed vector diagram of the combination of the first planetary carrier, the second ring gear and the third ring gear provided by the embodiment of the present application; Figure 2 , Figure 3 , Figure 4

[0024] Figure 6 is a speed vector diagram of the first planetary carrier, the second ring gear and the third ring gear when the speed N4 is 0 provided by the embodiment of the present application; ​

[0025] Figure 7 is a rotational speed vector diagram when the rotational speed N4 of the first carrier, the second ring gear and the third ring gear is less than 0 according to an embodiment of the present application;

[0026] Figure 8 is a rotational speed vector diagram when the rotational speed N1 of the first driving member is 0 according to an embodiment of the present application;

[0027] Figure 9 is a rotational speed vector diagram when the rotational speeds of the first sun gear and the second sun gear are the same according to an embodiment of the present application;

[0028] Figure 10 is a rotational speed vector diagram when the rotational directions of the rotational speeds N1 and N2 of the first sun gear and the second sun gear are both positive according to an embodiment of the present application;

[0029] Figure 11 is a rotational speed vector diagram when the rotational speed N4 of the first carrier, the second ring gear and the third ring gear is 0 in the reverse operation according to an embodiment of the present application;

[0030] Figure 12 is a rotational speed vector diagram when the rotational speed N4 of the first carrier, the second ring gear and the third ring gear is less than 0 in the reverse operation according to an embodiment of the present application;

[0031] Figure 13 is a rotational speed vector diagram when the rotational direction of the rotational speed N2 of the second sun gear driven by the second driving member is positive when the first driving member fails according to an embodiment of the present application;

[0032] Figure 14 is a rotational speed vector diagram when the rotational direction of the rotational speed N1 of the first driving member is reverse when the second driving member fails according to an embodiment of the present application.

[0033] Reference signs:

[0034] 1 - first planetary gear set, 101 - first sun gear, 102 - first carrier, 103 - first ring gear, 2 - second planetary gear set, 201 - second sun gear, 202 - second carrier, 203 - second ring gear, 3 - third planetary gear set, 301 - third sun gear, 302 - third carrier, 303 - third ring gear, 4 - transmission stage, 401 - transmission gear A, 402 - transmission gear B, 5 - one-way clutch, 6 - first input shaft, 7 - second input shaft, 8 - connecting shaft, 9 - output component, 10 - transmission shaft. DETAILED DESCRIPTION

[0035] First we have to explain the purpose of our invention embodiment, we are to solve the AMT transmission shift jerk, power interruption problems; AMT transmission ratio range is subject to gear settings, applied in heavy vehicles, in order to expand the range of transmission ratio, need to set a very large number of gear, shift process is slow, complex operation, resulting in many big car drivers reluctant to step on the brake; AMT transmission shift process depends on complex control strategy, it is difficult to grasp the accurate shift timing, there is high energy consumption, low efficiency problem; AMT transmission structure is complex, high manufacturing cost, maintenance difficulties and other existing problems, so a kind of three planetary row stepless speed change mechanism of hierarchical input is proposed to solve the existing problems.

[0036] The embodiments of the present application will be described in detail below with reference to the drawings. First, we will introduce the specific structure of the embodiments of the present application.

[0037] Referring to Figure 1 A kind of three planetary row stepless speed change mechanism of hierarchical input, including first planetary row 1, second planetary row 2, third planetary row 3 and transmission stage 4, the transmission stage 4 includes transmission gear A401 and transmission gear B402, the transmission gear A401 and the transmission gear B402 are engaged by external gear, the first ring gear 103 on the first planetary row 1 is connected with the second carrier 202 on the second planetary row 2, the second carrier 202 on the second planetary row 2 is connected with the third sun gear 301 on the third planetary row 3 through connecting shaft 8, the first carrier 102 on the first planetary row 1 is connected with the second ring gear 203 on the second planetary row 2 and the third ring gear 303 on the third planetary row 3, the connection body of the first carrier 102, the second ring gear 203 and the third ring gear 303 is provided with one-way stopper 5, the third carrier 302 on the third planetary row 3 is connected with output component 9, the first sun gear 101 on the first planetary row 1 is connected with transmission gear B402 through transmission shaft 10, the second input shaft 7 connected with the second sun gear 201 on the second planetary row 2 passes through the first sun gear 101, the transmission shaft 10 and the transmission gear B402 and is connected with second driving part, the transmission gear A401 on the transmission stage 4 is connected with first driving part through first input shaft 6.

[0038] Referring to Figure 1The outer teeth of the first sun gear 101 mesh with first planetary gears, the first planetary gears are installed on the first planet carrier 102, and the first planetary gears mesh with the inner ring teeth of the first ring gear 103; the outer teeth of the second sun gear 201 mesh with second planetary gears, the second planetary gears are installed on the second planet carrier 202, and the second planetary gears mesh with the inner ring teeth of the second ring gear 203; the outer teeth of the third sun gear 301 mesh with third planetary gears, the third planetary gears are installed on the third planet carrier 302, and the third planetary gears mesh with the inner ring teeth of the third ring gear 303.

[0039] Referring to Figure 1 The one-way stopper 5 is used to limit the rotation direction of the first planet carrier 102, the second ring gear 203 and the third ring gear 303, and the rotation direction of the first planet carrier 102, the second ring gear 203 and the third ring gear 303 is consistent with the rotation direction of the second driving member only.

[0040] Next, we need to combine the specific structure of the embodiment of the application to explain a speed change method of a three-planet row stepless speed change mechanism based on hierarchical input.

[0041] According to the basic principle of the planetary gear, the rotation speed of any two components of the sun gear, the ring gear and the planet carrier is determined, and the rotation speed of the other component is also determined, and their rotation speed relationship is in a corresponding proportional relationship according to the number of teeth of the sun gear and the number of teeth of the ring gear.

[0042] According to the basic principle of the planetary gear, the rotation speed of any two components of the sun gear, the ring gear and the planet carrier is the same, and the rotation speed of the other component is also the same.

[0043] Therefore, the rotation speed of the second driving member and the rotation speed of the second sun gear 201 are the same, and are set as N2; the rotation speed of the first driving member is set as N1x i, and the rotation speed of the first sun gear 101 is N1; the rotation speed of the first ring gear 103, the second planet carrier 202 and the third sun gear 301 is the same, and is set as N3; the rotation speed of the first planet carrier 102, the second ring gear 203 and the third ring gear 303 is the same, and is set as N4; the rotation speed of the third planet carrier 302 and the output component 9 is the same, and is set as N5; the number of teeth of the first sun gear 101 is set as Z1, the number of teeth of the first ring gear 103 is set as Z2, the number of teeth of the second sun gear 201 is set as Z3, the number of teeth of the second ring gear 203 is set as Z4, the number of teeth of the third sun gear 301 is set as Z5, and the number of teeth of the third ring gear 303 is set as Z6.

[0044] According to the rotation speed vector calculation method of the planetary gear, the rotation speed vector diagram of the first planet row 1 is obtained, as shown in Figure 2As shown. N1 is the speed of the first sun gear 101, N3 is the speed of the first ring gear 103, and N4 is the speed of the first planet carrier 102. The lengths of N1, N3, and N4 represent the speeds, and the arrows indicate the speeds. An upward arrow indicates forward speed, and a downward arrow indicates reverse speed. Set L2 / L3 = Z1 / Z2.

[0045] According to the planetary gear speed vector calculation method, the speed vector diagram of the second planetary gear 2 is obtained, as shown in the figure: Figure 3 As shown. N2 is the speed of the second sun gear 201, N4 is the speed of the second ring gear 203, and N3 is the speed of the second planet carrier 202. The lengths of N2, N3, and N4 represent the speeds, and the arrows represent the speeds. An upward arrow indicates forward speed, and a downward arrow indicates reverse speed. Set L2 / L1 = Z3 / Z4.

[0046] According to the planetary gear speed vector calculation method, the speed vector diagram of the third planetary gear 3 is obtained, as shown in the figure: Figure 4 As shown in the figure, N3 is the speed of the third sun gear 301, N4 is the speed of the third ring gear 303, and N5 is the speed of the third planet carrier 302. The lengths of N3, N4, and N5 represent the speeds, and the arrows indicate the direction of the speeds. An upward arrow indicates forward speed, and a downward arrow indicates reverse speed. Set L5 / L4 = Z5 / Z6.

[0047] exist Figure 2 、 Figure 3 and Figure 4 In the calculation, L1, L2, L3, L4, and L5 only need to satisfy the corresponding proportional relationship. The actual lengths of L1, L2, L3, L4, and L5 do not affect the calculation of the sizes of N1, N2, N3, N4, and N5. Figure 2 、 Figure 3 、 Figure 4 Merge Figure 5 , let L2=L4+L5.

[0048] See also Figure 5 , N2 is the rotational speed of the second sun gear 201, that is, the rotational speed of the second driving member; N1 is the rotational speed of the first sun gear 101; N3 is the rotational speed of the first ring gear 103, the second planetary carrier 202 and the third sun gear 301; N4 is the rotational speed of the first planetary carrier 102, the second ring gear 203 and the third ring gear 303; N5 is the rotational speed of the third planetary carrier 302 and the output component 9.

[0049] If any two of N1, N2, N3, N4, and N5 are determined, the remaining three values ​​can be calculated using the proportional relationship of the line segments in the vector diagram. Specifically, if the rotational speed N1 of the first sun gear 101 and the rotational speed N2 of the second sun gear 201 are determined, the rotational speed N5 of the output component 9 is also uniquely determined. By adjusting and controlling the rotational speeds N1 and N2 of the first sun gear 101 and 201 through the first and second drive elements, the rotational speed N5 of the output component 9 can be continuously and steplessly varied.

[0050] The speed change principle of the three-planet gear continuously variable transmission mechanism with graded input according to the embodiment of the present invention will be described below in conjunction with specific working conditions.

[0051] 1. Starting conditions

[0052] See also Figure 5 and Figure 6 When starting, the first driving member drives the first sun gear 101 at a speed of N1 and the direction is reverse, and the second driving member drives the second sun gear 201 at a speed of N2 and the direction is forward. The two driving members start to accelerate at the same time, and by controlling the ratio of the speed N2 of the second sun gear 201 to the speed N1 of the first sun gear 101 to be always greater than (such as Figure 5 ) or equal to (such as Figure 6 )[Z1×(Z3+Z4)] / (Z2×Z3), the speed N5 of the output component 9 can be gradually accelerated from 0 and turned to the forward direction. In this operating condition, the transmission ratio is maximized, and the power of the first and second drive components is coupled together, reducing speed and increasing torque output, accelerating the vehicle forward.

[0053] 2. Acceleration and deceleration conditions

[0054] The acceleration and deceleration process can be divided into three cases according to the direction of the first sun gear speed N1, including:

[0055] 1) Case 1

[0056] See also Figure 5 and Figure 6 The first drive element drives the first sun gear 101 at a rotational speed of N1, with the direction of rotation being reverse, and the second drive element drives the second sun gear 201 at a rotational speed of N2, with the direction of rotation being forward. By controlling the ratio of the rotational speed N2 of the second sun gear 201 to the rotational speed N1 of the first sun gear 101 to always be greater than or equal to [Z1×(Z3+Z4)] / (Z2×Z3), the first and second drive elements control the speed of increase or decrease of the rotational speeds N1 and N2 of the first and second sun gears 101 and 201, thereby gradually increasing or decreasing the rotational speed N5 of the output component 9, with the direction of rotation being forward, thereby accelerating or decelerating the vehicle forward.

[0057] 2) Case 2

[0058] Referring to Figure 8 , the first driving member drives the first sun gear 101 at a speed of N1, which gradually decreases to 0, and the second driving member drives the second sun gear 201 at a speed of N2, which is positive. By controlling the speed N1 of the first sun gear 101 and the speed N2 of the second sun gear 201, the output speed N5 can be gradually increased or decreased, and the vehicle can be accelerated or decelerated to move forward.

[0059] 3) Case three

[0060] Referring to Figure 10 , the first driving member drives the first sun gear 101 at a speed of N1, which is positive, and the second driving member drives the second sun gear 201 at a speed of N2, which is positive. By controlling the speed N1 of the first sun gear 101 and the speed N2 of the second sun gear 201, the output speed N5 can be gradually increased or decreased, and the vehicle can be accelerated or decelerated to move forward.

[0061] In addition, the speed regulation method of acceleration and deceleration can also be to maintain the speed N1 of the first driving member unchanged, and to regulate the speed N5 of the output member 9 by regulating the speed N2 of the second driving member; or to maintain the speed N2 of the second driving member unchanged, and to regulate the speed N5 of the output member 9 by regulating the speed N1 of the first driving member. In the process of realizing the acceleration or deceleration of the output member 9, the first driving member and the second driving member can be controlled according to the different high-efficiency working zones, and the control system can control the acceleration, deceleration and maintenance speed of the first driving member and the second driving member according to the current working condition. In this way, the first driving member and the second driving member can work in the respective high-efficiency working zones for a long time, so that the energy-saving effect is realized.

[0062] 3) Maximum vehicle speed working condition

[0063] Referring to Figure 9 and Figure 10 , the first driving member drives the first sun gear 101 at a speed of N1, which is positive, and the second driving member drives the second sun gear 201 at a speed of N2, which is positive. When the speed N1 of the first sun gear 101 and the speed N2 of the second sun gear 201 reach the maximum speed, the speed N5 of the output member 9 also reaches the maximum speed, and at this time the vehicle speed reaches the maximum speed. If the maximum speeds of the first sun gear 101 and the second sun gear 201 are the same, the maximum speed of the output member 9 is also the same as the maximum speeds N1 and N2 of the first sun gear 101 and the second sun gear 201, and at this time the transmission ratio is 1.

[0064] For the above starting conditions and acceleration and deceleration conditions, there is a dangerous condition that needs to be considered how to avoid.

[0065] Example: see Figure 7 When the first driving member drives the first sun gear 101 to rotate at a speed N1 in the reverse direction, the second driving member drives the second sun gear 201 to rotate at a speed N2 in the forward direction, and the vehicle is running in the starting stage or low-speed stage, if the first driving member and the second driving member speed control is not accurate or control failure, the ratio of the speed N2 of the second sun gear 201 to the speed N1 of the first sun gear 101 is less than [Z1×(Z3+Z4)] / (Z2×Z3), as shown in Figure 7 , the direction of the speed N5 of the output member 9 may appear to be in the reverse direction, at this time the vehicle suddenly appears to be running in reverse, which is prone to serious accidents. In order to prevent this situation from happening, by setting a one-way stopper 5 on the connecting body of the first planetary carrier 102, the second ring gear 203 and the third ring gear 303, the direction of the speed N4 of the first planetary carrier 102, the second ring gear 203 and the third ring gear 303 is limited to be forward only, not reverse. In this way, the direction of the speed N5 of the output member 9 is always forward. Therefore, when this dangerous condition occurs, since the one-way stopper 5 limits the direction of the speed N4 of the first planetary carrier 102, the second ring gear 203 and the third ring gear 303 to be forward only, not reverse, at this time the two driving members will drag each other, the ratio of the speed N2 of the second sun gear 201 to the speed N1 of the first sun gear 101 will always be equal to [Z1×(Z3+Z4)] / (Z2×Z3), the speed N4 of the first planetary carrier 102, the second ring gear 203 and the third ring gear 303 is equal to 0, the direction of the speed N5 of the output member 9 can only be forward, so there will be no sudden reverse driving situation.

[0066] 4. Reverse driving condition

[0067] See Figure 11 and Figure 12 , when reversing, the first driving member drives the first sun gear 101 to rotate at a speed N1 in the forward direction, and the second driving member drives the second sun gear 201 to rotate at a speed N2 in the reverse direction. Two driving members are started simultaneously and accelerated, by controlling the ratio of the speed N2 of the second sun gear 201 to the speed N1 of the first sun gear 101 to be always greater than (such as Figure 12 ) or equal to (such as Figure 11) / (Z2 x Z3), the rotation direction of the output member 9 can be reversed. If the rotation speed control of the first driving member and the second driving member is inaccurate or fails, and the ratio of the rotation speed N2 of the second sun gear 201 to the rotation speed N1 of the first sun gear 101 is less than [Z1 x (Z3 + Z4) ] / (Z2 x Z3), the rotation direction of the output member 9 can be positive, which can cause the vehicle to suddenly move forward and result in a serious accident. In order to prevent this situation, the one-way stopper 5 is arranged on the connecting body of the first planet carrier 102, the second ring gear 203 and the third ring gear 303, so that the rotation direction of the first planet carrier 102, the second ring gear 203 and the third ring gear 303 can only be reversed, but cannot be positive. In this way, the rotation direction of the output member 9 is always reversed.

[0068] In addition to the normal working condition and the dangerous working condition, some emergency working conditions also need to be coped with, and the embodiments of the present application have considered and solved the same.

[0069] For example, referring to Figure 13 When the first driving member fails, the rotation speed of the second driving member is N2, the rotation direction is positive, the rotation speed N4 of the first planet carrier 102, the second ring gear 203 and the third ring gear 303 has a reverse trend, at this time the one-way stopper 5 limits the reverse, so that the rotation speed N4 of the first planet carrier 102, the second ring gear 203 and the third ring gear 303 is 0, the rotation speed N5 of the output member 9 is positive, the power of the second driving member is output through the second planetary gear set 2 and the third planetary gear set 3, the transmission ratio is [(Z3 + Z4) x (Z5 + Z6) ] / (Z3 x Z5), so that the vehicle can continue to accelerate or decelerate to move forward.

[0070] For example, referring to Figure 14 When the second driving member fails, the rotation speed of the first driving member driving the first sun gear is N1, the rotation direction is reversed, the rotation speed N4 of the first planet carrier 102, the second ring gear 203 and the third ring gear 303 has a reverse trend, at this time the one-way stopper 5 limits the reverse, so that the rotation speed N4 of the first planet carrier 102, the second ring gear 203 and the third ring gear 303 is 0, the rotation speed N5 of the output member 9 is positive, the power of the first driving member is output through the transmission stage, the first planetary gear set 1 and the third planetary gear set 3, the transmission ratio is i x [Z2 x (Z5 + Z6) / Z1 x Z5], so that the vehicle can continue to accelerate or decelerate to move forward.

[0071] Therefore, when one driving member fails, the other driving member can still drive the vehicle to run, although the power is reduced, but one driving member can drive the vehicle to a repair site or a safe site, and the reliability of the vehicle can be greatly improved.

[0072] The three-planet row continuously variable transmission mechanism with hierarchical input and the transmission method thereof have the following advantages.

[0073] 1. The three-planet row continuously variable transmission mechanism with hierarchical input has no power interruption during speed regulation, and runs quietly and stably, so that users have a better driving experience, and the product can greatly meet the customer demand in the sense, and lays a very good foundation for the promotion and use of the product.

[0074] 2. The three-planet row continuously variable transmission mechanism with hierarchical input can realize large torque at the output end from low speed to high speed, so that the vehicle has the ability of rapid acceleration start during driving, and the large torque can climb a larger slope during climbing, and the large torque can meet the driving demand of more people, so that the audience of the product is larger.

[0075] 3. The three-planet row continuously variable transmission mechanism with hierarchical input can realize stepless and continuous change of the output speed, the input driving member can work in the high-efficiency interval for a long time, improves the work efficiency, and can be more energy-saving in the use of energy, and can make more contributions in energy saving.

[0076] 4. The three-planet row continuously variable transmission mechanism with hierarchical input has simple and convenient speed regulation, only needs to control the rotation speeds of the first driving member and the second driving member, can realize stepless and continuous change of the output speed, reduces the requirement of the vehicle on the control system, and makes the promotion and use range of the product more extensive, and guarantees the promotion and popularity of the product to a certain extent.

[0077] 5. The power of the first driving member and the second driving member is coupled together to drive the vehicle to run, when one driving member fails, the other driving member can still drive the vehicle to run, guarantees that the vehicle owner can drive the vehicle by relying on the other driving member even if one driving member fails, and drives the vehicle to a repair site in time, avoids the occurrence of calling a tow truck event, and better takes care of the driving experience of the vehicle owner.

[0078] 6. Compared with the traditional single drive component driving mode, the product using the embodiment of the present invention can not only be driven by dual drive components, but also can select drive components with smaller volume and lower speed to match. The small-volume drive components are more conducive to the layout design of the drive components in the vehicle body, and are more convenient for the aesthetic design of the vehicle body appearance in the later stage. In addition, the use of smaller drive components can save costs.

[0079] 7. The three-planet gear continuously variable transmission mechanism with graded input in the embodiment of the present invention has a high transmission rate. Under the same working conditions, a motor with lower power and lower speed can be selected as a driving part. Compared with high-power batteries, low-power batteries can better prevent the occurrence of battery overheating. The embodiment of the present invention indirectly improves the safety of battery use.

[0080] 8. The three-planet gear continuously variable transmission mechanism with graded input in the embodiment of the present invention adopts a three-planet gear transmission, which increases the transmission ratio and further increases the torque. It can be used on heavy vehicles such as trucks, dump trucks, and buses with larger loads, further broadening the scope of application of the embodiment of the present invention.

[0081] 9. The three-planet gear continuously variable transmission mechanism with graded input in the embodiment of the present invention arranges the first drive member and the second drive member on the same side of the continuously variable transmission mechanism, and arranges the output member 9 on the other side of the transmission mechanism, so that the input and output positions can be better separated, reducing the probability of mutual interference between the input end and the output member 9. Such a design can greatly improve the utilization rate of space, making the entire power equipment more reasonable in layout and space occupancy.

[0082] 10. The three-planetary gear continuously variable transmission mechanism with graded input in the embodiment of the present invention is provided with a transmission stage 4 between the first input shaft 6 and the transmission shaft 10. The transmission stage 4 changes the gear ratio of the transmission gear A401 and the transmission gear B402 to achieve the purpose of changing the transmission ratio between the first driving member and the first sun gear 101. Therefore, under the premise of achieving the same use effect, the transmission ratio provided by the transmission stage 4 broadens the power selection range of the first driving member.

[0083] The above technical solutions only reflect the preferred technical solutions of the technical solutions of the present invention. Any changes that may be made to certain parts thereof by those skilled in the art all reflect the principles of the present invention and fall within the scope of protection of the present invention.

Claims

1. A speed change method for a three-planet gear continuously variable transmission mechanism with graded input, characterized in that: The three-planetary gear continuously variable transmission mechanism with graded input comprises a first planetary gear (1), a second planetary gear (2), a third planetary gear (3) and a transmission stage (4), wherein the transmission stage (4) comprises a transmission gear A (401) and a transmission gear B (402), wherein the transmission gear A (401) and the transmission gear B (402) are meshed with external teeth, the first ring gear (103) on the first planetary gear (1) is connected to the second planetary gear carrier (202) on the second planetary gear (2), the second planetary gear carrier (202) is connected to the third sun gear (301) on the third planetary gear (3) via a connecting shaft (8), the first planetary gear carrier (102) on the first planetary gear (1) is connected to the second ring gear (203) on the second planetary gear (2) and the third planetary gear carrier ( 3), a one-way stopper (5) is provided on the connecting body of the first planet carrier (102), the second ring gear (203) and the third ring gear (303), the third planet carrier (302) on the third planetary gear (3) is connected with an output component (9), the first sun gear (101) on the first planetary gear (1) is connected to the transmission gear B (402) through a transmission shaft (10), the second input shaft (7) connected to the second sun gear (201) on the second planetary gear (2) passes through the first sun gear (101), the transmission shaft (10) and the transmission gear B (402) to be connected to the second driving member, and the transmission gear A (401) on the transmission stage (4) is connected to the first driving member through a first input shaft (6); The first planetary gear is meshed with the outer teeth of the first sun gear (101), the first planetary gear is mounted on the first planet carrier (102), and the first planetary gear is meshed with the inner ring teeth of the first ring gear (103); The second sun gear (201) is meshed with a second planetary gear on its outer teeth, the second planetary gear is mounted on the second planet carrier (202), and the second planetary gear is meshed with an inner ring gear of the second ring gear (203); The outer teeth of the third sun gear (301) are meshed with a third planetary gear, the third planetary gear is mounted on the third planet carrier (302), and the third planetary gear is meshed with the inner ring teeth of the third ring gear (303); The one-way stopper (5) is used to limit the rotation direction of the first planet carrier (102), the second ring gear (203) and the third ring gear (303), and the one-way stopper (5) makes the rotation direction of the first planet carrier (102), the second ring gear (203) and the third ring gear (303) only consistent with the rotation direction of the second driving member; The second driving member and the second sun gear (201) are connected via the second input shaft (7), so that the rotational speed of the second driving member is the same as the rotational speed of the second sun gear (201); the first driving member and the first sun gear (101) are connected via the first input shaft (6), the transmission stage (4), and the transmission shaft (10), so that the rotational speed of the first driving member and the rotational speed of the first sun gear (101) are proportional to the transmission ratio of the transmission stage (4); the first planet carrier (102), the second ring gear (203), and the third ring gear (303) are connected, so that the first planet carrier (102), the second The ring gear (203) and the third ring gear (303) have the same rotational speed; the first ring gear (103), the second planetary carrier (202) and the third sun gear (301) are connected so that the first ring gear (103), the second planetary carrier (202) and the third sun gear (301) have the same rotational speed; the output component (9) is connected to the third planetary carrier (302) so that the third planetary carrier (302) and the output component (9) have the same rotational speed; by adjusting and controlling the rotational speed of the first driving component and the rotational speed of the second driving component, the rotational speed of the output component (9) is continuously changed, and in this process, the speed ratio also changes accordingly.

2. The speed change method of the three-planet gear continuously variable transmission mechanism with stepped input according to claim 1, characterized in that: Assume that: the rotational speed of the second driving member and the rotational speed of the second sun gear (201) are N2, the rotational speed of the first sun gear (101) is N1, the transmission ratio of the transmission stage (4) is i, the rotational speed of the first driving member is N1×i, the rotational speed of the first ring gear (103), the second planetary carrier (202) and the third sun gear (301) is N3, the rotational speed of the first planetary carrier (102), the second ring gear (203) and the third ring gear (303) is N4, the rotational speed of the third planetary carrier (302) and the output member (9) is N5, the number of teeth of the first sun gear (101) is Z1, the number of teeth of the first ring gear (103) is Z2, the number of teeth of the second sun gear (201) is Z3, the second The number of teeth of the ring gear (203) is Z4, the number of teeth of the third sun gear (301) is Z5, and the number of teeth of the third ring gear (303) is Z6. When any two values ​​of N1, N2, N3, N4 and N5 are determined, the other three values ​​can be calculated through the proportional relationship of the line segments in the vector diagram; by driving the first driving member and the second driving member to adjust and control the rotation speed N1 of the first sun gear (101) and the rotation speed N2 of the second sun gear (201), the rotation speed N5 of the output component (9) can be continuously and steplessly changed; by adjusting and controlling the rotation speed N1 of the first sun gear (101) and the rotation speed N2 of the second sun gear (201), the output state of the output component (9) includes state A, state B, state C, state D and state E.

3. The speed change method of the three-planet gear continuously variable transmission mechanism with stepped input according to claim 2, characterized in that: In the state A, the first driving member drives the first sun gear (101) at a speed of N1, and the direction of rotation is reverse; the second driving member drives the second sun gear (201) at a speed of N2, and the direction of rotation is forward; the ratio of the speed N2 of the second sun gear (201) to the speed N1 of the first sun gear (101) is equal to [Z1×(Z3+Z4)] / (Z2×Z3); the speed N4 of the first planet carrier (102), the second ring gear (203) and the third ring gear (303) is 0; and the direction of rotation of the speed N5 of the output component (9) is forward.

4. The speed change method of the three-planet gear continuously variable transmission mechanism with stepped input according to claim 2, characterized in that: In the state B, the first driving member drives the first sun gear (101) at a rotational speed of N1, which is in the reverse direction; the second driving member drives the second sun gear (201) at a rotational speed of N2, which is in the forward direction; the ratio of the rotational speed N2 of the second sun gear (201) to the rotational speed N1 of the first sun gear (101) is greater than [Z1×(Z3+Z4)] / (Z2×Z3); the rotational speeds N4 of the first planetary carrier (102), the second ring gear (203) and the third ring gear (303) are in the forward direction; and the rotational speed N5 of the output component (9) is in the forward direction.

5. The speed change method of the three-planet gear continuously variable transmission mechanism with stepped input according to claim 2, characterized in that: In the state C, the first driving member drives the first sun gear (101) at a speed of N1, and the direction of rotation is reverse; the second driving member drives the second sun gear (201) at a speed of N2, and the direction of rotation is forward; the ratio of the speed N2 of the second sun gear (201) to the speed N1 of the first sun gear (101) is less than [Z1×(Z3+Z4)] / (Z2×Z3); the first planet carrier (102), the second ring gear (203) and the third ring gear (303) are The rotational speed N4 is in the reverse direction, and the rotational speed N5 of the output component (9) is in the forward direction or the reverse direction. In order to prevent this from happening, a one-way stopper (5) is provided on the connecting body of the first planetary carrier (102), the second ring gear (203) and the third ring gear (303), so as to limit the rotational speed N4 of the first planetary carrier (102), the second ring gear (203) and the third ring gear (303) to only be in the forward direction and not in the reverse direction, thereby ensuring that the rotational speed N5 of the output component (9) is always in the forward direction.

6. The speed change method of the three-planet gear continuously variable transmission mechanism with stepped input according to claim 2, characterized in that: In the state D, the rotational speed N1 of the first sun gear (101) driven by the first driving member is 0, the rotational speed N2 of the second sun gear (201) driven by the second driving member is positive, the rotational speed N4 of the first planet carrier (102), the second ring gear (203) and the third ring gear (303) is positive, and the rotational speed N5 of the output component (9) is positive.

7. The speed change method of the three-planet gear continuously variable transmission mechanism with stepped input according to claim 2, characterized in that: In the state E, the rotational speed N1 of the first sun gear (101) driven by the first driving member and the rotational speed N2 of the second sun gear (201) driven by the second driving member are the same in magnitude, and the directions of rotation are both positive; the rotational speed N4 of the first planetary carrier (102), the second ring gear (203) and the third ring gear (303) are the same in magnitude as the N1 and the N2, and the directions of rotation are both positive; the rotational speed N5 of the output component (9) is the same in magnitude as the N1, the N2 and the N4, and the directions of rotation are both positive; and the transmission ratio of the state E is 1.

8. The speed change method of the three-planet gear continuously variable transmission mechanism with stepped input according to claim 2, characterized in that: When the first driving member fails, the speed of the second driving member is N2, and the direction of rotation is reverse. The speed of the second sun gear (201) is N2, and the direction of rotation is forward. The speed N4 of the first planetary carrier (102), the second ring gear (203) and the third ring gear (303) has a reverse trend. At this time, the one-way stopper (5) limits their reverse rotation, so that the speed N4 of the first planetary carrier (102), the second ring gear (203) and the third ring gear (303) is 0. The speed N5 of the output component (9) rotates forward. The power of the second driving member is output through the second planetary gear (2) and the third planetary gear (3) with deceleration and torque increase. The transmission ratio is [(Z3+Z4)×(Z5+Z6)] / (Z3×Z5).

9. The speed changing method of the three-planet gear continuously variable transmission mechanism with stepped input according to claim 2, characterized in that: When the second driving member fails, the first driving member drives the first sun gear (101) at a speed of N1 in the reverse direction, and the speed N4 of the first planetary carrier (102), the second ring gear (203) and the third ring gear (303) has a reverse trend. At this time, the one-way stopper (5) limits the reverse rotation, so that the speed N4 of the first planetary carrier (102), the second ring gear (203) and the third ring gear (303) is 0, and the speed N5 of the output component (9) rotates in the forward direction. The power of the first driving member is decelerated and torque-increased through the transmission stage (4), the first planetary gear (1) and the third planetary gear (3), and the transmission ratio is i×[Z2×(Z5+Z6)] / (Z1×Z5).

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