A single-output parallel multi-mode continuously variable transmission with dual-flow synchronous transmission during gear shifting and its shift control method.

Abstract

This invention discloses a single-flow output parallel multi-mode continuously variable transmission (CVT) with dual-flow synchronous transmission during gear shifting. It includes an input shaft assembly, a mechanical transmission mode assembly, a hydraulic transmission mode assembly, and an output shaft transmission assembly. The input shaft assembly includes a clutch. Both the mechanical and hydraulic transmission mode assemblies are equipped with synchronizers, forming two parallel power transmission paths. Power is ultimately output to the output shaft transmission assembly via one of these two components. The shift control method of this CVT discloses that, during adjacent gear changes, the variable pump in the hydraulic transmission mode assembly ensures that the transmission ratio of the hydraulic transmission path matches that of the mechanical transmission path. This invention achieves synchronous transmission of both mechanical and hydraulic flows during gear shifts, reducing shift shock and enabling uninterrupted power shifting for off-road vehicles.

Description

Technical Field

[0001] This invention relates to a composite transmission device and its shift control method, belonging to the technical field of transmission devices. Background Technology

[0002] Agricultural vehicles, engineering vehicles, and military vehicles operate in harsh environments with heavy loads, preventing them from fully utilizing their engine power. Therefore, to improve their ability to withstand high-intensity loads, non-road vehicles commonly employ hydraulic mechanical shifting transmission technology. Hydraulic transmission features low speed and high torque; however, its transmission efficiency is low. Gear-based mechanical transmissions have high transmission efficiency, but their load-bearing capacity is poor, they experience shifting shocks, and they cannot achieve continuously variable transmissions.

[0003] Existing hydraulic-mechanical continuously variable transmissions (HMCVTs) combine the stepless speed regulation of hydraulic transmission with the high efficiency of mechanical transmission. However, the power transmitted by an HMCVT requires coupling between mechanical and hydraulic transmissions, resulting in lower transmission efficiency compared to purely mechanical transmissions. Furthermore, the mechanical components of an HMCVT typically consist of planetary gear sets and gears, leading to a complex structure, high manufacturing and maintenance costs, and the inability to implement modular design. Some simple parallel-structured hydraulic-mechanical transmission solutions treat hydraulic transmission as a separate transmission mode, switching between traditional multi-speed mechanical transmissions and hydraulic transmissions. However, multi-speed mechanical transmissions still exhibit shift shock during gear changes. Summary of the Invention

[0004] To address the shortcomings of the existing technology, this invention provides a single-flow output parallel multi-mode continuously variable transmission (CVT) with dual-flow synchronous transmission during gear shifting and its shift control method. The objectives are: 1. To increase the transmission ratio variation range in multiple stages using a modular design; 2. To significantly reduce shift shock; theoretically, with high speed regulation accuracy, shift shock can be eliminated; 3. The modular design allows for the addition of mechanical gears, increasing the frequency of mechanical transmission and improving the transmission system efficiency.

[0005] The technical solution of the present invention is as follows: a single-flow output parallel multi-mode continuously variable transmission with dual-flow synchronous transmission during gear shifting, comprising an input shaft assembly, a mechanical transmission mode assembly, a hydraulic transmission mode assembly, and an output shaft transmission assembly;

[0006] The input shaft assembly includes an input shaft and a clutch assembly;

[0007] The mechanical transmission mode component includes a mechanical transmission shaft, a plurality of mechanical driven gears, a mechanical input synchronizer, a plurality of mechanical driving gears, and a plurality of mechanical output synchronizers. The mechanical driven gears and mechanical driving gears are loosely fitted onto the mechanical transmission shaft. The mechanical input synchronizer and the mechanical output synchronizer are fixedly connected to the mechanical transmission shaft. The mechanical input synchronizer causes at most one of the plurality of mechanical driven gears to rotate synchronously with the mechanical transmission shaft, and the mechanical output synchronizer causes at most one of the plurality of mechanical driving gears to rotate synchronously with the mechanical transmission shaft.

[0008] The hydraulic transmission mode assembly includes a variable pump, a fixed displacement motor, several hydraulic driven gears, a hydraulic input synchronizer, several hydraulic drive gears, and several hydraulic output synchronizers. The variable pump has a variable pump input shaft, the hydraulic driven gears are loosely fitted on the variable pump input shaft, and the hydraulic input synchronizer is fixedly connected to the variable pump input shaft so that at most one of the hydraulic driven gears rotates synchronously with the variable pump input shaft. The variable pump drives the fixed displacement motor to rotate. The fixed displacement motor has a fixed displacement motor output shaft, the hydraulic drive gears are loosely fitted on the fixed displacement motor output shaft, and the hydraulic output synchronizer is fixedly connected to the fixed displacement motor output shaft so that the several hydraulic drive gears rotate synchronously with the fixed displacement motor output shaft.

[0009] The clutch assembly is used to engage or disengage the power transmission from the input axis to the mechanical driven gear, and to engage or disengage the power transmission from the input axis to the hydraulic driven gear; power

[0010] The output shaft transmission assembly includes an output shaft and several output driven gears. The several output driven gears are connected to the output shaft and rotate synchronously. The output driven gears mesh with the mechanical driving gear and the hydraulic driving gear.

[0011] Furthermore, the mechanical transmission shaft is provided with a first one-way overrunning clutch, the mechanical driven gear is loosely fitted on the input shaft of the first one-way overrunning clutch, the mechanical driving gear is loosely fitted on the output shaft of the first one-way overrunning clutch, the mechanical input synchronizer is fixedly connected to the input shaft of the first one-way overrunning clutch, and the mechanical output synchronizer is fixedly connected to the output shaft of the first one-way overrunning clutch.

[0012] Furthermore, the output shaft of the quantitative motor is provided with a second one-way overrunning clutch, the output shaft of the quantitative motor serves as the input shaft of the second one-way overrunning clutch, the hydraulic drive gear is loosely fitted on the output shaft of the second one-way overrunning clutch, and the hydraulic output synchronizer is fixedly connected to the output shaft of the second one-way overrunning clutch.

[0013] Furthermore, the clutch assembly includes a first clutch assembly and a second clutch assembly, the mechanical driven gear includes a first driven gear and a second driven gear, and the hydraulic driven gear includes a third driven gear and a fourth driven gear. The first clutch assembly engages or disengages the power transmission of the input axis to the first driven gear and the third driven gear simultaneously, and the second clutch assembly engages or disengages the power transmission of the input axis to the second driven gear and the fourth driven gear simultaneously.

[0014] Furthermore, the transmission ratios of the first driven gear and the second driven gear are different when transmitting power along the input axis, and the transmission ratios of the third driven gear and the fourth driven gear are different when transmitting power along the input axis.

[0015] Furthermore, the number of the mechanical driving gear, the hydraulic driving gear, and the output driven gear are all the same, and one output driven gear meshes with one mechanical driving gear and one hydraulic driving gear simultaneously.

[0016] Furthermore, the number of the mechanical driving gears is the same as and greater than the number of the output driven gears.

[0017] Another technical solution of the present invention is: a shift control method for a single-output parallel multi-mode continuously variable transmission with dual-flow synchronous transmission during gear shifting, wherein the clutch assembly, mechanical input synchronizer, mechanical output synchronizer, hydraulic input synchronizer, and hydraulic output synchronizer are controlled to perform gear shifting; adjacent gear shifting is achieved by transmitting the power from the input shaft to the output shaft via the mechanical transmission shaft or the output shaft of the fixed displacement motor, and the displacement ratio of the variable pump is controlled so that the transmission ratio of the power transmitted from the output shaft via the fixed displacement motor to the output shaft during adjacent gear shifting is the same as the transmission ratio of the power transmitted from the mechanical transmission shaft to the output shaft.

[0018] Furthermore, when starting in first gear, the clutch assembly and the hydraulic input synchronizer are controlled to engage the power transmission of the input axis to the hydraulic driven gear, and the hydraulic output synchronizer is controlled to transmit power through the output axis of the fixed displacement motor.

[0019] Compared with the prior art, the advantages of the technical solution provided by the present invention are as follows:

[0020] This invention utilizes two parallel power transmission routes, switched via a clutch assembly and synchronizer, enabling uninterrupted gear shifting for off-road vehicles. It reduces intermediate mechanisms in the transmission process, minimizing power loss and improving transmission efficiency. Furthermore, the transmission device of this invention has a simple and compact structure, high repeatability of transmission components, and is easily modularized. The number of gears can be increased by increasing the number of meshing pairs of the mechanical drive gear, hydraulic drive gear, and output driven gear.

[0021] The operating mode during start-up can be hydraulic transmission, which can meet the high torque requirements during start-up. Furthermore, the clutch assembly can remain engaged during start-up, greatly reducing the load on the clutch assembly, extending its service life, and lowering maintenance costs.

[0022] By controlling the displacement ratio of the variable pump, a shift point is set when the transmission ratios of the hydraulic and mechanical working modes are the same. At the shift point, the transmission paths of both working modes operate simultaneously to complete the shift. Theoretically, this can eliminate shift shock, reduce the requirements of the transmission system on the shift actuators, increase the service life of related components, and save maintenance costs.

[0023] It can continuously adjust speed according to changes in resistance during driving, and has a multi-stage transmission with a wide range of transmission ratios, which can bring out the best performance of the engine, improve the fuel economy of off-road vehicles, and extend the service life of the engine. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the single-flow output parallel multi-mode continuously variable transmission with dual-flow synchronous transmission during gear shifting, as shown in Example 1.

[0025] Figure 2 This is a schematic diagram of the structure of the single-flow output parallel multi-mode continuously variable transmission with dual-flow synchronous transmission during gear shifting in Example 2.

[0026] Figure 3 The variable pump displacement ratio variation diagram is shown for the first control method of the single-flow output parallel multi-mode continuously variable transmission with dual-flow synchronous transmission during gear shifting in Example 1.

[0027] Figure 4 This is a graph showing the change in the variable pump displacement ratio of the second control method for a single-flow output parallel multi-mode continuously variable transmission with dual-flow synchronous drive during gear shifting in Example 1.

[0028] Figure 5 The variable pump displacement ratio variation diagram is shown for the control method of the single-flow output parallel multi-mode continuously variable transmission with dual-flow synchronous transmission during gear shifting in Example 2.

[0029] Figure 6This is a power transmission route diagram for the first control method in Example 1, showing the forward gear 1st gear.

[0030] Figure 7 This is a power transmission route diagram for the first control method in Example 1, representing the forward two-gear power transmission path.

[0031] Figure 8 This is a power transmission route diagram for the first control method in Example 1, showing the forward 3rd gear.

[0032] Figure 9 This is a forward 4-gear power transmission route diagram for the first control method in Example 1.

[0033] Figure 10 This is a forward 5-speed power transmission route diagram for the first control method in Example 1.

[0034] Figure 11 This is a forward 6-speed power transmission route diagram for the first control method in Example 1.

[0035] Figure 12 This is a power transmission route diagram for the first control method in Example 1, showing the forward 7-speed power transmission path.

[0036] Figure 13 This is a forward 8-speed power transmission route diagram for the first control method in Example 1.

[0037] Figure 14 This is a power transmission route diagram for the first gear in the second control method of Example 1.

[0038] Figure 15 This is a power transmission route diagram for the second control method in Example 1, representing the forward two-gear power transmission path.

[0039] Figure 16 This is a power transmission route diagram for the third gear in the second control method of Example 1.

[0040] Figure 17 This is a forward 4-gear power transmission route diagram for the second control method in Example 1.

[0041] Figure 18 This is a forward 5-speed power transmission route diagram for the second control method in Example 1.

[0042] Figure 19 This is a forward 6-speed power transmission route diagram for the second control method in Example 1.

[0043] Figure 20 This is a power transmission route diagram for the 7th gear forward using the second control method in Example 1.

[0044] Figure 21 This is a forward 8-speed power transmission route diagram for the second control method in Example 1.

[0045] Figure 22 This is a power transmission route diagram for advancing one gear in the hydraulic working mode of Example 2.

[0046] Figure 23 This is a power transmission route diagram for the hydraulic working mode of Example 2, which is two gears ahead.

[0047] Figure 24 The diagram shows the power transmission route for advancing one gear in the mechanical working mode of Example 2.

[0048] Figure 25 The diagram shows the power transmission route for advancing two gears in the mechanical working mode of Example 2.

[0049] Figure 26 The diagram shows the power transmission route for the mechanical working mode of Example 2, which involves moving forward three gears.

[0050] Figure 27 The diagram shows the power transmission route for the mechanical working mode of Example 2, which involves moving forward 4 gears.

[0051] Figure 28 The diagram shows the power transmission route for advancing 5 gears in the mechanical working mode of Example 2.

[0052] Figure 29 The diagram shows the power transmission route for the mechanical working mode of Example 2, which involves advancing 6 gears.

[0053] Figure 30 The diagram shows the power transmission route for the mechanical working mode of Example 2, which involves advancing 7 gears.

[0054] Figure 31 The diagram shows the power transmission route for advancing 8 gears in the mechanical working mode of Example 2. Detailed Implementation

[0055] The present invention will be further described below with reference to embodiments. It should be understood that these embodiments are only for illustrating the present invention and are not intended to limit the scope of the present invention. After reading this description, any modifications of this description in various equivalent forms by those skilled in the art will fall within the scope defined by the appended claims.

[0056] Example 1

[0057] Please combine Figure 1 As shown, the single-flow output parallel multi-mode continuously variable transmission with dual-flow synchronous transmission during gear shifting in this embodiment includes: an input shaft assembly, a hydraulic transmission mode assembly, a mechanical transmission mode assembly, and an output shaft transmission assembly.

[0058] The input shaft assembly includes an input shaft 101, a first clutch assembly 106, and a second clutch assembly 107.

[0059] The mechanical transmission mode assembly includes a first overrunning clutch input shaft 103, a first synchronizer 108, a second synchronizer 109, a first driven gear 116, a second driven gear 117, a first driving gear 118, a second driving gear 119, a first one-way overrunning clutch 124, and a first one-way overrunning clutch output shaft 125. The first synchronizer 108 is fixed to the first one-way overrunning clutch input shaft 103, and the second synchronizer 109 is fixed to the first one-way overrunning clutch output shaft 125.

[0060] The first driven gear 116 and the second driven gear 117 are loosely fitted on the input shaft 103 of the first one-way overrunning clutch, and the first driving gear 118 and the second driving gear 119 are loosely fitted on the output shaft 125 of the first one-way overrunning clutch.

[0061] The input shaft 103 of the first one-way overrunning clutch is connected to the output shaft 125 of the first one-way overrunning clutch via the first one-way overrunning clutch 124. The first one-way overrunning clutch 124 can make its input shaft and output shaft rotate synchronously when the speed of its input shaft is greater than the speed of its output shaft, and otherwise the input shaft and output shaft are disconnected.

[0062] The first driven gear 116 engages with the input shaft 103 of the first one-way overrunning clutch via the first synchronizer 108 to the left, and transmits power via the output gear of the first clutch assembly 106 when the first clutch assembly 106 is engaged.

[0063] The second driven gear 117 engages with the first one-way overrunning clutch input shaft 103 via the first synchronizer 108, and is connected to the input shaft 101 via the output gear of the second clutch assembly 107 when the second clutch assembly 107 is engaged.

[0064] The first driving gear 118 and the second driving gear 119 are connected to the output shaft 102 by meshing with the fifth driven gear 114 and the sixth driven gear 115, respectively. The first driving gear 118 is connected to the output shaft 125 of the first one-way overrunning clutch by engaging to the left through the second synchronizer 109, and the second driving gear 119 is connected to the output shaft 125 of the first one-way overrunning clutch by engaging to the right through the second synchronizer 109.

[0065] The hydraulic transmission mode assembly includes a variable pump input shaft 104, a fixed displacement motor output shaft 105, a third driven gear 120, a third synchronizer 110, a fourth driven gear 121, a variable pump 111, a fixed displacement motor 112, a third drive gear 122, a fourth synchronizer 113, a fourth drive gear 123, a second one-way overrunning clutch 126, and a second one-way overrunning clutch output shaft 127.

[0066] The third synchronizer 110 is fixed to the variable pump input shaft 104, and the fourth synchronizer 113 is fixed to the second one-way overrunning clutch output shaft 127. The third driven gear 120 and the fourth driven gear 121 are loosely fitted on the variable pump input shaft 104. The third driving gear 122 and the fourth driving gear 123 are loosely fitted on the second one-way overrunning clutch output shaft 127.

[0067] The third driven gear 120 and the fourth driven gear 121 are connected to the input shaft 101 via the first clutch assembly 106 and the second clutch assembly 107, respectively. The third driven gear 120 engages to the left via the third synchronizer 110 and is connected to the variable pump input shaft 104. The fourth driven gear engages to the right via the third synchronizer 110 and is connected to the variable pump input shaft 104. The third driving gear 122 and the fourth driving gear 123 engage with the fifth driven gear 114 and the sixth driven gear 115, respectively, and are connected to the output shaft 102. The third driving gear 122 engages to the left via the fourth synchronizer 113 and is connected to the output shaft 127 of the second one-way overrunning clutch. The fourth driving gear 123 engages to the right via the fourth synchronizer 113 and is connected to the output shaft 127 of the second one-way overrunning clutch.

[0068] The output shaft 105 of the fixed displacement motor is connected to the output shaft 127 of the second one-way overrunning clutch 126. The second one-way overrunning clutch 126 can make the input shaft (output shaft 105 of the fixed displacement motor) rotate synchronously with the output shaft when the speed of the input shaft is greater than the speed of the output shaft, and otherwise the input shaft and output shaft are disconnected.

[0069] The output shaft assembly includes an output shaft 102, a fifth driven gear 114, and a sixth driven gear 115. The fifth driven gear 14 and the sixth driven gear 115 are fixedly connected to the output shaft 102.

[0070] This embodiment presents two shift control methods for a single-flow output parallel multi-mode continuously variable transmission with dual-flow synchronous drive during shifting, which will be described below.

[0071] The first control method is as follows:

[0072] The third synchronizer 110 engages to the left, the fourth synchronizer 113 engages to the left, the first clutch assembly 106 engages, and the second clutch assembly 107 disengages. As the swashplate angle of the variable pump 111 increases, the variable pump 111 outputs high-pressure oil to drive the fixed displacement motor 112 to rotate forward, and the transmission is in forward first gear; the operating mode is hydraulic transmission mode. Furthermore, in this operating mode, the first clutch assembly 106, the third synchronizer 110, and the fourth synchronizer 113 all engage in advance. Therefore, the damage to the aforementioned transmission components is minimal during vehicle start-up. The power transmission route is as follows: Figure 6As shown; the transmission ratio in hydraulic transmission mode changes with the displacement ratio as follows: Figure 3 The forward gear 1 line is shown.

[0073] When the displacement ratio of the variable pump 111 is controlled so that the gear ratio of forward 1st gear is about to reach the gear ratio of forward 2nd gear; that is, as Figure 3 As shown, the Mode 1 line and the Mode 2 line intersect at a displacement ratio of 1; at this time, the first synchronizer 108 engages to the right, and the second synchronizer 109 engages to the left; the first clutch assembly 106 disengages, and the second clutch assembly 107 engages, putting the transmission in forward 2nd gear; the operating mode is mechanical transmission mode. The power transmission route is as follows: Figure 7 As shown; in the mechanical transmission mode, the transmission ratio remains unchanged, such as... Figure 3 The forward 2nd gear line is shown.

[0074] By adjusting the displacement ratio of the variable pump 111, the transmission ratio of forward 3rd gear is made the same as that of forward 2nd gear, i.e. Figure 3 As shown, the Mode 2 line and the Mode 3 line intersect at a displacement ratio of 0.5; at this time, the third synchronizer 110 engages to the left, the fourth synchronizer 113 engages to the right, the first clutch assembly 106 engages, the second clutch assembly 107 disengages, and the variable pump 111 outputs high-pressure oil to drive the fixed displacement motor 112 to rotate forward. This transmission device is in forward 3rd gear; the working mode is hydraulic transmission mode. The power transmission route is as follows: Figure 8 As shown; the transmission ratio in hydraulic transmission mode changes with the displacement ratio as follows: Figure 3 The forward 3rd gear line is shown.

[0075] By adjusting the displacement ratio of variable pump 111, the forward 3rd gear ratio is about to reach the forward 4th gear ratio; that is, as... Figure 3 As shown, mode 3 and mode 4 lines intersect at a displacement ratio of 1. The first synchronizer 108 engages to the right, the second synchronizer 109 engages to the right, the first clutch assembly 106 disengages, and the second clutch assembly 107 engages. This transmission is in forward 4th gear; the operating mode is mechanical transmission mode. The power transmission route is as follows: Figure 9 As shown; the transmission ratio does not change in the mechanical transmission mode.

[0076] By adjusting the displacement ratio of the variable pump 111, the transmission ratio of forward 5th gear is made the same as the transmission ratio of forward 4th gear in mode, i.e. Figure 3 As shown, mode 4 and mode 5 intersect at a displacement ratio of 0.5. The third synchronizer 110 engages to the right, and the fourth synchronizer 113 engages to the left. The first clutch assembly 106 disengages, and the second clutch assembly 107 engages. The variable pump 111 outputs high-pressure oil to drive the fixed displacement motor 112 to rotate forward. This transmission device is in forward 5th gear; the operating mode is hydraulic transmission mode. The power transmission route is as follows... Figure 10 As shown; the transmission ratio in hydraulic transmission mode changes with the displacement ratio as follows: Figure 3The forward 5th gear line is shown.

[0077] By adjusting the displacement ratio of variable pump 111, the forward 5th gear ratio is about to reach the forward 6th gear ratio; that is, as... Figure 3 As shown, mode 5 and mode 6 lines intersect at a displacement ratio of 1. The first synchronizer 108 engages to the left, the second synchronizer 109 engages to the left, the first clutch assembly 106 engages, and the second clutch assembly 107 disengages. This transmission device is in mechanical transmission mode, forward 6th gear; the operating mode is mechanical transmission mode. The power transmission route is as follows: Figure 11 As shown; the transmission ratio does not change in the mechanical transmission mode.

[0078] By adjusting the displacement ratio of the variable pump 111, the transmission ratio of the 7th gear forward is made the same as that of the 6th gear forward, i.e. Figure 3 As shown, mode 6 and mode 7 lines intersect at a displacement ratio of 0.5. The third synchronizer 110 engages to the right, the fourth synchronizer 113 engages to the right, the first clutch assembly 106 disengages, and the second clutch assembly 107 engages. The variable pump 111 outputs high-pressure oil to drive the fixed displacement motor 112 to rotate forward. This transmission device is in hydraulic transmission mode, moving forward in 7th gear. The power transmission route in hydraulic transmission mode is as follows: Figure 12 As shown; the transmission ratio in hydraulic transmission mode changes with the displacement ratio as follows: Figure 3 The forward 7th gear line is shown.

[0079] When the displacement ratio of the variable pump 111 is controlled so that the hydraulic transmission mode forward 8 gears are about to reach the mechanical transmission mode forward 8 gears; that is, when... Figure 3 As shown, mode 7 and mode 8 intersect at a displacement ratio of 1. The first synchronizer 108 engages to the left, and the second synchronizer 109 engages to the right. The first clutch assembly 106 engages, and the second clutch assembly 107 disengages. This transmission device is in mechanical transmission mode, forward 8th gear. The power transmission route is as follows: Figure 13 As shown; the transmission ratio does not change in the mechanical transmission mode.

[0080] The transmission ratios for each gear obtained by this control method are shown in the table below.

[0081]

[0082]

[0083] Among them, i 01 This indicates the transmission ratio between the first driven gear 116 and the first clutch assembly 106; 02 This indicates the transmission ratio between the second clutch assembly 107 and the second driven gear 117; 03 This indicates the transmission ratio between the first driving gear 118 and the fifth driven gear 114; 04This indicates the transmission ratio between the second driving gear 119 and the sixth driven gear 115; 11 This indicates the transmission ratio between the first clutch assembly 106 and the third driven gear 120; 12 This indicates the transmission ratio between the second clutch assembly 107 and the fourth driven gear 121; 13 This indicates the transmission ratio between the third driving gear 122 and the fifth driven gear 114; i 14 represents the transmission ratio between the fourth driving gear 123 and the sixth driven gear 115; e represents the displacement ratio when the variable pump 111 is working.

[0084] The second control method is as follows:

[0085] The third synchronizer 110 engages to the left, the fourth synchronizer 113 engages to the left, the first clutch assembly 106 engages, the second clutch assembly 107 disengages, the first clutch assembly 106 drives the variable pump 111 to work, the variable pump 111 outputs high-pressure oil to drive the fixed displacement motor 112 to rotate forward, and this transmission device is in hydraulic transmission mode, moving forward in first gear; the power transmission route is as follows. Figure 14 As shown; the variable transmission ratio in hydraulic transmission mode changes with the displacement ratio as follows: Figure 4 The forward gear 1 line is shown.

[0086] When the displacement ratio of the variable pump 111 is controlled so that the hydraulic transmission mode advances one gear, the transmission ratio is about to reach the mechanical transmission mode advances two gears; that is, when... Figure 4 As shown, the Mode 1 line and the Mode 2 line intersect at a displacement ratio of 1; the first synchronizer 108 engages to the left, the second synchronizer 109 engages to the left, the first clutch assembly 106 engages, and the second clutch assembly 107 disengages. This transmission device is in mechanical transmission mode, forward 2nd gear; the power transmission route is as follows... Figure 15 As shown; in mechanical transmission mode, the transmission ratio remains unchanged, such as... Figure 4 The forward 2nd gear line is shown.

[0087] By adjusting the displacement ratio of the variable pump 111, the forward gear ratio in hydraulic transmission mode (3rd gear) is made the same as the forward gear ratio in mechanical transmission mode (2nd gear), i.e. Figure 4 As shown, the mode 2 line and the mode 3 line intersect at a displacement ratio of 0.5; the third synchronizer 110 engages to the left, the fourth synchronizer 113 engages to the right, the first clutch assembly 106 engages, the second clutch assembly 107 disengages, and the variable pump 111 outputs high-pressure oil to drive the fixed displacement motor 112 to rotate forward. This transmission device is in hydraulic transmission mode, moving forward in 3rd gear; the power transmission route is as follows. Figure 16 As shown; the transmission ratio in hydraulic transmission mode changes with the displacement ratio as follows: Figure 4 The forward 3rd gear line is shown.

[0088] When the displacement ratio of variable pump 111 is adjusted so that the hydraulic transmission mode's forward 3rd gear ratio is about to reach the mechanical transmission mode's forward 4th gear ratio; that is... Figure 4 As shown, mode 3 and mode 4 lines intersect at a displacement ratio of 1. The first synchronizer 108 engages to the left, the second synchronizer 109 engages to the right, the first clutch assembly 106 engages, and the second clutch assembly 107 disengages. The transmission is in mechanical operating mode, forward 4th gear. The power transmission route is as follows: Figure 17 As shown; the transmission ratio does not change in the mechanical transmission mode.

[0089] By adjusting the displacement ratio of the variable pump 111, the transmission ratio of forward 5 gears in hydraulic transmission mode is made the same as that in forward 4 gears in mechanical transmission mode, i.e. Figure 4 As shown, mode 4 and mode 5 intersect at a displacement ratio of 0.5. The third synchronizer 110 engages to the right, and the fourth synchronizer 113 engages to the left. The first clutch assembly 106 disengages, and the second clutch assembly 107 engages. The variable pump 111 outputs high-pressure oil to drive the fixed displacement motor 112 to rotate forward. This transmission device is in hydraulic transmission mode, moving forward in 5th gear. The power transmission route is as follows: Figure 18 As shown; the transmission ratio in hydraulic transmission mode changes with the displacement ratio as follows: Figure 4 The forward 5th gear line is shown.

[0090] When the displacement ratio of variable pump 111 is adjusted so that the hydraulic transmission mode forward 5 gears is about to reach the mechanical transmission mode forward 6 gears, that is... Figure 4 As shown, mode 5 and mode 6 intersect at a displacement ratio of 1. The first synchronizer 108 engages to the right, and the second synchronizer 109 engages to the left. The first clutch assembly 106 disengages, and the second clutch assembly 107 engages. This transmission is in mechanical operating mode, forward gear 6. The power transmission route is as follows: Figure 19 As shown; the transmission ratio does not change in the mechanical transmission mode.

[0091] By adjusting the displacement ratio of the variable pump 111, the forward gear ratio in hydraulic transmission mode (7th gear) is made the same as the forward gear ratio in mechanical transmission mode (6th gear). Figure 4 In the shown mode, line 6 and line 7 intersect at a displacement ratio of 0.5. The third synchronizer 110 engages to the right, the fourth synchronizer 113 engages to the right, the first clutch assembly 106 disengages, and the second clutch assembly 107 engages. The variable pump 111 outputs high-pressure oil to drive the fixed displacement motor 112 to rotate forward. This transmission device is in hydraulic transmission mode, moving forward in 7th gear. The power transmission route is as follows: Figure 20 As shown; the transmission ratio in hydraulic transmission mode changes with the displacement ratio as follows: Figure 4 The forward 7th gear line is shown.

[0092] When the displacement ratio of the variable pump 111 is controlled so that the hydraulic transmission mode advances 7 gears and is about to reach the mechanical transmission mode advances 8 gears; that is, when... Figure 4 In the shown pattern, line 7 and line 8 intersect at a displacement ratio of 1. The first synchronizer 108 engages to the right, the second synchronizer 109 engages to the right, the first clutch assembly 106 disengages, and the second clutch assembly 107 engages. The transmission is in mechanical operating mode, forward gear 8. The power transmission route is as follows: Figure 21 As shown; the transmission ratio remains unchanged in the mechanical transmission mode.

[0093] The transmission ratios for each gear obtained by this control method are shown in the table below.

[0094]

[0095]

[0096] Example 2

[0097] Please combine Figure 2 As shown, the single-flow output parallel multi-mode continuously variable transmission with dual-flow synchronous transmission during gear shifting in this embodiment includes: an input shaft assembly, a hydraulic transmission mode assembly, a mechanical transmission mode assembly, and an output shaft transmission assembly.

[0098] The input shaft assembly includes an input shaft 201, a first clutch assembly 206, and a second clutch assembly 207.

[0099] The hydraulic transmission mode assembly includes a variable pump input shaft 204, a fixed displacement motor output shaft 205, a fourth synchronizer 211, a variable pump 212, a fixed displacement motor 213, a fifth synchronizer 214, a second one-way overrunning clutch 230, a second one-way overrunning clutch output shaft 231, a third driven gear 219, a fourth driven gear 220, and a fifth driving gear 221.

[0100] The fourth synchronizer 211 is fixed to the variable pump input shaft 204, and the fifth synchronizer 214 is fixed to the second one-way overrunning clutch output shaft 231. The third driven gear 219 and the fourth driven gear 220 are loosely fitted on the variable pump input shaft 204, and the fifth driving gear 221 is loosely fitted on the second one-way overrunning clutch output shaft 231.

[0101] The third driven gear 219 and the fourth driven gear 220 are connected to the input shaft 201 through the first clutch assembly 206 and the second clutch assembly 207, respectively. The third driven gear 219 is engaged to the left through the fourth synchronizer 211 and connected to the variable pump input shaft 204. The fourth driven gear 220 is engaged to the right through the fourth synchronizer 211 and connected to the variable pump input shaft 204.

[0102] The fifth driving gear 221 is connected to the output shaft 202 by meshing with the fifth driven gear 215, and the fifth driving gear 221 is connected to the output shaft 231 of the second one-way overrunning clutch by engaging with the fifth synchronizer 214.

[0103] The output shaft 205 of the fixed displacement motor is connected to the output shaft 231 of the second one-way overrunning clutch via the second one-way overrunning clutch 230.

[0104] The intermediate shaft transmission assembly includes a first one-way overrunning clutch input shaft 203, a first synchronizer 208, a second synchronizer 209, a third synchronizer 210, a first one-way overrunning clutch 228, a first one-way clutch output shaft 229, a first driven gear 222, a second driven gear 223, a first driving gear 224, a second driving gear 225, a third driving gear 226, and a fourth driving gear 227.

[0105] The first synchronizer 208 and the second synchronizer 209 are fixedly connected to the input shaft 203 of the first one-way overrunning clutch. The third synchronizer 210 is fixedly connected to the output shaft 229 of the first one-way overrunning clutch. The first driven gear 222, the second driven gear 223, the first driving gear 224, the second driving gear 225, the third driving gear 226, and the fourth driving gear 227 are loosely fitted on the shaft.

[0106] The first driven gear 222 and the second driven gear 223 are connected to the input shaft 201 through the first clutch assembly 206 and the second clutch assembly 207, respectively. The first driven gear 222 is engaged to the left through the first synchronizer 208 and connected to the input shaft 203 of the first one-way overrunning clutch. The second driven gear is engaged to the right through the first synchronizer 208 and connected to the input shaft 203 of the first one-way overrunning clutch.

[0107] The first driving gear 224 is connected to the output shaft 202 by meshing with the fifth driven gear 215, and is connected to the output shaft 229 of the first one-way overrunning clutch by engaging to the left through the second synchronizer 209.

[0108] The second driving gear 225 is connected to the output shaft 202 by meshing with the sixth driven gear 216, and is connected to the output shaft 229 of the first one-way overrunning clutch by engaging to the right through the second synchronizer 209.

[0109] The third driving gear 226 is connected to the output shaft 202 by meshing with the seventh driven gear 217, and is connected to the output shaft 229 of the first one-way overrunning clutch by engaging to the left through the third synchronizer 210.

[0110] The fourth driving gear 227 is connected to the output shaft 202 by meshing with the eighth driven gear 18, and is connected to the first one-way overrunning clutch output shaft 229 by engaging with the third synchronizer 210 to the right.

[0111] The output shaft drive assembly includes an output shaft 202, a fifth driven gear 215, a sixth driven gear 216, a seventh driven gear 217, and an eighth driven gear 18, which are fixedly connected to the output shaft 202.

[0112] The shift control method of the dual-flow synchronous transmission single-flow output parallel multi-mode continuously variable transmission in this embodiment is as follows:

[0113] The fourth synchronizer 211 engages to the left, and the fifth synchronizer 214 engages. The first clutch assembly 206 engages, and the second clutch assembly 207 disengages. The first clutch assembly 206 drives the variable pump 212 to work. As the swashplate angle of the variable pump 212 increases, the variable pump outputs high-pressure oil to drive the fixed displacement motor 213 to rotate in the forward direction. At this time, the transmission system starts to work, and this transmission device is in the first forward gear of the hydraulic transmission mode. The power transmission route is as follows: Figure 22 As shown.

[0114] When the displacement ratio of the variable pump 212 is about to reach the forward gear ratio of the hydraulic transmission mode (first gear), the first synchronizer 208 engages to the right, the second synchronizer 209 engages to the left, the first clutch assembly 206 disengages, the second clutch assembly 207 engages, and the transmission device is in the forward gear of the mechanical transmission mode. The power transmission route is as follows: Figure 23 As shown.

[0115] The displacement ratio of the variable pump 212 is controlled to bring the hydraulic transmission mode forward 2 gears to the mechanical transmission mode forward 1 gear ratio. The fourth synchronizer 211 engages to the right, the fifth synchronizer 214 engages, the first clutch assembly 206 disengages, and the second clutch assembly 207 engages. The variable pump outputs high-pressure oil to drive the fixed displacement motor to rotate forward. This transmission device is in hydraulic transmission mode forward 2 gears. The power transmission route is as follows: Figure 24 As shown.

[0116] When the displacement ratio of the variable pump 212 is controlled so that the forward gear ratio of the hydraulic transmission mode is about to reach the forward gear ratio of the mechanical transmission mode, the first synchronizer 208 engages to the left, the second synchronizer 209 engages to the left, the first clutch assembly 206 engages, the second clutch assembly 207 disengages, and the transmission device is in the forward gear of the mechanical transmission mode. The power transmission route is as follows: Figure 25 As shown.

[0117] The displacement ratio of the variable pump 212 is controlled so that the transmission ratio of the hydraulic transmission mode forward 1 gear reaches the transmission ratio of the mechanical transmission mode forward 2 gears. The fourth synchronizer 211 engages to the left, the fifth synchronizer 214 engages, the first clutch assembly 206 engages, and the second clutch assembly 207 disengages. At this time, the transmission device is in the hydraulic transmission mode forward 1 gear.

[0118] When the displacement ratio of the variable pump 212 is controlled so that the hydraulic transmission mode's forward gear ratio is about to reach the mechanical transmission mode's forward gear ratio, the first synchronizer 208 engages to the right, the second synchronizer 209 engages to the right, the first clutch assembly 206 disengages, the second clutch assembly 207 engages, and the transmission device is in mechanical transmission mode forward gear 3. The power transmission route is as follows: Figure 26 As shown.

[0119] Controlling the displacement ratio of the variable pump enables the transmission ratio of the hydraulic transmission mode to advance 2 gears, which is equivalent to the transmission ratio of the mechanical transmission mode to advance 3 gears. The fourth synchronizer 211 engages to the right, the fifth synchronizer 214 engages, the first clutch assembly 206 disengages, and the second clutch assembly 207 engages. At this time, the transmission device is in the hydraulic transmission mode, advancing 2 gears.

[0120] When the displacement ratio of the variable pump 212 is adjusted so that the hydraulic transmission mode's forward 2nd gear ratio is about to reach the mechanical transmission mode's forward 4th gear ratio, the first synchronizer 208 engages to the left, the second synchronizer 209 engages to the right, the first clutch assembly 206 engages, and the second clutch assembly 207 disengages. The transmission device is then in mechanical transmission mode forward 4th gear, and the power transmission route is as follows: Figure 27 As shown.

[0121] The displacement ratio of the variable pump 212 is controlled so that the transmission ratio of the hydraulic transmission mode forward 1 gear reaches the transmission ratio of the mechanical transmission mode forward 4 gears. The fourth synchronizer 211 engages to the left, the fifth synchronizer 214 engages, the first clutch assembly 206 engages, and the second clutch assembly 207 disengages. At this time, the transmission device is in the hydraulic transmission mode forward 1 gear.

[0122] When the displacement ratio of the variable pump 212 is adjusted so that the hydraulic transmission mode's forward gear ratio is about to reach the mechanical transmission mode's forward gear ratio, the first synchronizer 208 engages to the right, the third synchronizer 210 engages to the left, the first clutch assembly 206 disengages, and the second clutch assembly 207 engages. The transmission is then in mechanical transmission mode, forward gear 5. The power transmission route is as follows: Figure 28 As shown.

[0123] The displacement ratio of the variable pump 212 is controlled so that the transmission ratio of the hydraulic transmission mode forward 2 gears reaches the transmission ratio of the mechanical transmission mode forward 5 gears. The fourth synchronizer 211 engages to the right and the fifth synchronizer 214 engages. The first clutch assembly 206 disengages and the second clutch assembly 207 engages. At this time, the transmission device is in the hydraulic transmission mode forward 2 gears.

[0124] When the displacement ratio of the variable pump 212 is adjusted so that the hydraulic transmission mode's forward 2nd gear ratio is about to reach the mechanical transmission mode's forward 6th gear ratio, the first synchronizer 208 engages to the left, the third synchronizer 11 engages to the left, the first clutch assembly 206 engages, the second clutch assembly 207 disengages, and the transmission device is in mechanical transmission mode forward 6th gear. The power transmission route is as follows: Figure 29 As shown.

[0125] The displacement ratio of the variable pump 212 is controlled so that the transmission ratio of the hydraulic transmission mode forward 1 gear reaches the transmission ratio of the mechanical transmission mode forward 6 gears. The fourth synchronizer 211 engages to the left, the fifth synchronizer 214 engages, the first clutch assembly 206 engages, and the second clutch assembly 207 disengages. At this time, the transmission device is in the hydraulic transmission mode forward 1 gear.

[0126] When the displacement ratio of the variable pump 212 is adjusted so that the hydraulic transmission mode's forward gear ratio is about to reach the mechanical transmission mode's forward gear ratio, the first synchronizer 208 engages to the right, the third synchronizer 210 engages to the right, the first clutch assembly 206 disengages, the second clutch assembly 207 engages, and the transmission device is in mechanical transmission mode forward gear 7. The power transmission route is as follows: Figure 30 As shown.

[0127] Controlling the displacement ratio of the variable pump enables the transmission ratio of the hydraulic transmission mode to advance 2 gears, which is equivalent to the transmission ratio of the mechanical transmission mode to advance 7 gears. The fourth synchronizer 211 engages to the right, the fifth synchronizer 214 engages, the first clutch assembly 206 disengages, and the second clutch assembly 207 engages. At this time, the transmission device is in the hydraulic transmission mode, advancing 2 gears.

[0128] When the displacement ratio of the variable pump 212 is adjusted so that the hydraulic transmission mode's forward 2nd gear ratio is about to reach the mechanical transmission mode's forward 8th gear ratio, the first synchronizer 208 engages to the left, the third synchronizer 210 engages to the right, the first clutch assembly 206 engages, and the second clutch assembly 207 disengages. The transmission device is then in mechanical transmission mode forward 8th gear, and the power transmission route is as follows: Figure 31 As shown.

[0129] The transmission ratios for each gear obtained by this control method are shown in the table below.

[0130] gear Change logic Hydraulic transmission mode forward 1st gear <![CDATA[i 11 *i 13 / e]]> Hydraulic transmission mode forward 2 gears <![CDATA[i 12 *i 13 / e]]> Mechanical transmission mode forward 1st gear <![CDATA[i 02 *i 03 ]]> Mechanical transmission mode forward 2 gears <![CDATA[i 01 *i 03 ]]> Mechanical transmission mode forward 3 gears <![CDATA[i 02 *i 04 ]]> Mechanical transmission mode forward 4 gears <![CDATA[i 01 *i 04 ]]> Mechanical transmission mode forward 5 gears <![CDATA[i 02 *i 05 ]]> Mechanical transmission mode forward 6 gears <![CDATA[i 01 *i 05 ]]> Mechanical transmission mode forward 7 gears <![CDATA[i 02 *i 06 ]]> Mechanical transmission mode forward 8 gears <![CDATA[i 01 *i 06 ]]>

Claims

1. A shift control method for a single-output parallel multi-mode continuously variable transmission (CVT) with dual-flow synchronous transmission during shifting, characterized in that, The single-flow output parallel multi-mode continuously variable transmission with dual-flow synchronous transmission during gear shifting includes an input shaft assembly, a mechanical transmission mode assembly, a hydraulic transmission mode assembly, and an output shaft transmission assembly. The input shaft assembly includes an input shaft and a clutch assembly; The mechanical transmission mode component includes a mechanical transmission shaft, a plurality of mechanical driven gears, a mechanical input synchronizer, a plurality of mechanical driving gears, and a plurality of mechanical output synchronizers. The mechanical driven gears and mechanical driving gears are loosely fitted onto the mechanical transmission shaft. The mechanical input synchronizer and the mechanical output synchronizer are fixedly connected to the mechanical transmission shaft. The mechanical input synchronizer causes at most one of the plurality of mechanical driven gears to rotate synchronously with the mechanical transmission shaft, and the mechanical output synchronizer causes at most one of the plurality of mechanical driving gears to rotate synchronously with the mechanical transmission shaft. The hydraulic transmission mode assembly includes a variable pump, a fixed displacement motor, several hydraulic driven gears, a hydraulic input synchronizer, several hydraulic drive gears, and several hydraulic output synchronizers. The variable pump has a variable pump input shaft, the hydraulic driven gears are loosely fitted onto the variable pump input shaft, and the hydraulic input synchronizer is fixedly connected to the variable pump input shaft so that at most one of the several hydraulic driven gears rotates synchronously with the variable pump input shaft. The variable pump drives the fixed displacement motor to rotate. The fixed displacement motor has a fixed displacement motor output shaft, the hydraulic drive gears are loosely fitted onto the fixed displacement motor output shaft, and the hydraulic output synchronizer is fixedly connected to the fixed displacement motor output shaft so that the several hydraulic drive gears rotate synchronously with the fixed displacement motor output shaft. The clutch assembly is used to engage or disengage the power transmission of the input axis to the mechanical driven gear, and to engage or disengage the power transmission of the input axis to the hydraulic driven gear. The output shaft transmission assembly includes an output shaft and a plurality of output driven gears. The plurality of output driven gears are connected to the output shaft and rotate synchronously. The output driven gears mesh with the mechanical driving gear and the hydraulic driving gear. The shift control method is based on the single-output parallel multi-mode continuously variable transmission with dual-flow synchronous transmission during shifting. It controls the clutch, mechanical input synchronizer, mechanical output synchronizer, hydraulic input synchronizer, and hydraulic output synchronizer to perform gear switching. Adjacent gear switching involves transmitting power from the input shaft to the output shaft via the mechanical transmission shaft or the output shaft of the fixed displacement motor. The displacement ratio of the variable pump is controlled so that the transmission ratio of power transmitted from the output shaft of the fixed displacement motor to the output shaft during adjacent gear switching is the same as the transmission ratio of power transmitted from the mechanical transmission shaft to the output shaft.

2. The shift control method for a single-stream output parallel multi-mode continuously variable transmission with dual-stream synchronous transmission during shifting, as described in claim 1, is characterized in that... The mechanical transmission shaft is equipped with a first one-way overrunning clutch. The mechanical driven gear is loosely fitted on the input shaft of the first one-way overrunning clutch, the mechanical driving gear is loosely fitted on the output shaft of the first one-way overrunning clutch, the mechanical input synchronizer is fixedly connected to the input shaft of the first one-way overrunning clutch, and the mechanical output synchronizer is fixedly connected to the output shaft of the first one-way overrunning clutch.

3. The shift control method for a single-stream output parallel multi-mode continuously variable transmission with dual-stream synchronous transmission during shifting, as described in claim 2, is characterized in that... The output shaft of the quantitative motor is provided with a second one-way overrunning clutch. The output shaft of the quantitative motor serves as the input shaft of the second one-way overrunning clutch. The hydraulic drive gear is loosely fitted onto the output shaft of the second one-way overrunning clutch. The hydraulic output synchronizer is fixedly connected to the output shaft of the second one-way overrunning clutch.

4. The shift control method for a single-flow output parallel multi-mode continuously variable transmission with dual-flow synchronous transmission during shifting, as described in any one of claims 1 to 3, is characterized in that... The clutch assembly includes a first clutch assembly and a second clutch assembly. The mechanical driven gear includes a first driven gear and a second driven gear. The hydraulic driven gear includes a third driven gear and a fourth driven gear. The first clutch assembly engages or disengages the power transmission of the input axis to the first driven gear and the third driven gear simultaneously. The second clutch assembly engages or disengages the power transmission of the input axis to the second driven gear and the fourth driven gear simultaneously.

5. The shift control method for a single-stream output parallel multi-mode continuously variable transmission with dual-stream synchronous transmission during shifting, as described in claim 4, is characterized in that... The transmission ratios of the first driven gear and the second driven gear are different when transmitting power along the input axis, and the transmission ratios of the third driven gear and the fourth driven gear are different when transmitting power along the input axis.

6. The shift control method for a single-stream output parallel multi-mode continuously variable transmission with dual-stream synchronous transmission during shifting, as described in claim 1, is characterized in that... The number of mechanical driving gears, hydraulic driving gears, and output driven gears are all the same, and one output driven gear meshes with one mechanical driving gear and one hydraulic driving gear simultaneously.

7. The shift control method for a single-stream output parallel multi-mode continuously variable transmission with dual-stream synchronous transmission during shifting, as described in claim 1, is characterized in that... The number of mechanical driving gears is the same as and greater than the number of hydraulic driving gears.

8. The shift control method for a single-flow output parallel multi-mode continuously variable transmission with dual-flow synchronous transmission during shifting, as described in claim 1, is characterized in that... When starting in first gear, the clutch and the hydraulic input synchronizer are controlled to engage the power transmission of the input axis to the hydraulic driven gear, and the hydraulic output synchronizer is controlled to transmit power through the output axis of the fixed displacement motor.

Images