CN211901516U

CN211901516U - Control system of continuously variable transmission

Info

Publication number: CN211901516U
Application number: CN202020275444.7U
Authority: CN
Inventors: 鞠苏成
Original assignee: Yangzhou Weibang Garden Machine Co Ltd
Current assignee: Yangzhou Weibang Garden Machine Co Ltd
Priority date: 2020-03-09
Filing date: 2020-03-09
Publication date: 2020-11-10
Anticipated expiration: 2030-03-09

Abstract

The utility model relates to a continuously variable transmission's control system, including big discharge capacity hydraulic pump, little discharge capacity hydraulic pump, hydraulic motor one, hydraulic motor two, solenoid directional valve one to solenoid directional valve four's P mouth links to each other with the pressure oil pipe of little discharge capacity hydraulic pump export respectively, solenoid directional valve one's A mouth links to each other with the control hydraulic fluid port of clutch one, solenoid directional valve two's A mouth links to each other with the control hydraulic fluid port of clutch two, solenoid directional valve three's A mouth links to each other with the control hydraulic fluid port of clutch three, solenoid directional valve four's A mouth links to each other with the control hydraulic fluid port of reverse gear clutch; the large-displacement hydraulic pump is controlled by the electro-hydraulic proportional valve I in displacement and flow direction and is connected with the hydraulic motor I through a power oil supply pipe; the second hydraulic motor is controlled by the second electro-hydraulic proportional valve to discharge, and is connected with the power oil supply pipe through the large-diameter electromagnetic directional valve. The utility model discloses can realize that the constant speed state trades the section, the speed governing is controllable in succession, and the nature controlled is good, and the reliability is high.

Description

Control system of continuously variable transmission

Technical Field

The utility model relates to a continuously variable transmission especially relates to a continuously variable transmission control system, has incessant continuously variable speed function of power, belongs to the derailleur technical field that wheeled vehicle used.

Background

The high-power self-propelled power machine always faces complex working conditions and has a large load change range, so that the high requirements on the speed regulation range, the torque, the transmission efficiency and the power continuity of the transmission are met. Especially, the high-power tractor is used as a main power machine in the agricultural field, the working condition is more complex, the power output cannot be interrupted, and the transmission of the high-power tractor needs better technical indexes, control performance and efficiency indexes.

The tractor brand on the existing market mostly adopts manual derailleur, non-intelligent part power transmission of shifting etc.. Especially, the tractor stepless speed change technology level is still in the stages of complex scheme, low efficiency, low reliability and poor controllability.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a first aim at overcomes the problem that exists among the prior art, provides a buncher control system, can realize that the constant speed state trades the section, and the speed governing is controllable in succession, and the nature controlled is good, and the reliability is high, and the transmission is steady efficient, whole power is incessant.

In order to solve the technical problem, the utility model discloses a continuously variable transmission control system, including big discharge capacity hydraulic pump B1, little discharge capacity hydraulic pump B2, hydraulic motor M1, hydraulic motor two M2, solenoid-operated valve K1, two K2 of solenoid-operated directional valve, three K3 of solenoid-operated directional valve and four K4 of solenoid-operated directional valve, one K1 of solenoid-operated directional valve, two K2 of solenoid-operated directional valve, three K3 of solenoid-operated directional valve and the P mouth of four K4 of solenoid-operated directional valve link to each other with the pressure oil pipe of little discharge capacity hydraulic pump B2 export respectively, the A mouth of one K1 of solenoid-operated directional valve links to each other with the control hydraulic fluid port of one C1 of clutch, the A mouth of two K2 of solenoid-operated directional valve links to each other with the control hydraulic port of two C2 of clutch, the A mouth of three K3 of solenoid-operated directional valve links to each other with the control hydraulic port of three C3 of clutch CR, the A mouth of four K4 of solenoid-; the large-displacement hydraulic pump B1 is controlled by the electro-hydraulic proportional valve I in displacement and flow direction and is connected with the hydraulic motor I M1 through a power oil supply pipe; the displacement of the hydraulic motor II M2 is controlled by an electro-hydraulic proportional valve II Y3, and the hydraulic motor II M2 is connected with the power oil supply pipe through a large-diameter electromagnetic directional valve Y4.

Compared with the prior art, the utility model discloses following beneficial effect has been obtained: the rotation direction of the large-displacement hydraulic pump B1 is kept unchanged, and the flow direction of the power oil supply pipe is changed by electrifying the left coil Y1 or the right coil Y2 of the electro-hydraulic proportional valve I; the control system gives a PWM signal which starts to gradually increase from 0 to the left coil Y1 or the right coil Y2 of the electro-hydraulic proportional valve I, and the output displacement of the large-displacement hydraulic pump B1 is gradually increased from 0; the large-drift-diameter electromagnetic reversing valve Y4 is powered off and is positioned at a parallel conduction station; the large-drift-diameter electromagnetic directional valve Y4 is electrified and is positioned at a cross conduction station, so that the large-drift-diameter electromagnetic directional valve Y4 is conveniently matched with the electro-hydraulic proportional valve I and is matched with the working states of the hydraulic motor I M1 and the hydraulic motor II M2 together. The signal pressure oil output by the small displacement hydraulic pump B2 controls the disengagement or combination of the first clutch C1, the second clutch C2, the third clutch C3 and the reverse clutch CR respectively through the first electromagnetic directional valve K1, the second electromagnetic directional valve K2, the third electromagnetic directional valve K3 and the fourth electromagnetic directional valve K4.

As an improvement of the present invention, the first clutch C1, the second clutch C2, the third clutch C3 and the reverse clutch CR are all sleeved on the first shaft a1 of the transmission, the first shaft a1 is further provided with a first gear G1, a third gear G3, a fifth gear G5 and a fifteenth gear G15, and the first gear G1 is fixed on the first shaft a1 and drives the large displacement hydraulic pump B1 through the second gear G2; gear three G3 is connected to shaft one a1 through clutch one C1 or to the transmission housing through clutch two C2; gear five G5 is connected to shaft one, a1, through clutch three, C3, and gear fifteen G15 is connected to shaft one, a1, through reverse clutch CR; a second shaft A2 of the transmission is sequentially provided with an eight-G8 gear, a four-G4 gear, a first planetary gear train and a second planetary gear train, wherein the eight-G8 gear is fixed on the second shaft A2 and is meshed with a seventh-G7 gear, and the seventh-G7 gear is arranged on a driving shaft of a first hydraulic motor M1; the first planetary gear train comprises a first sun gear S1, a first planet gear P1, a first planet carrier X1 and a first inner gear ring R1, the first planet carrier X1 is connected with a fourth gear G4 and is arranged on a second shaft A2 in a floating mode, and the fourth gear G4 is meshed with a third gear G3; the planetary gear train II comprises a sun gear II S2, a planet gear II P2, a planet carrier II X2 and an inner gear ring II R2, wherein the sun gear I S1 and the sun gear II S2 are both fixed on a shaft II A2, the inner gear ring I R1 is connected with the planet carrier II X2, and the center of the planet carrier II X2 is fixed at one end of the shaft II A4; the second ring gear R2 and the sixth gear G6 are fixed on the third shaft A3 together, the sixth gear G6 is meshed with the fifth gear G5, and the third shaft A3 is sleeved on the fourth shaft A4 in a floating mode and is coaxial.

The left end of the first shaft A1 can be connected with an engine flywheel disc, the first gear G1 drives the large-displacement hydraulic pump B1 to work through the second gear G2, and the large-displacement hydraulic pump B1 can provide power for the first hydraulic motor M1 and the second hydraulic motor M2. When the second clutch C2 is combined, the first planet carrier X1 of the first planetary gear train can be locked through the third gear G3, and the transmission mode of the planetary gear train is changed; parking may be achieved if the output displacement of the large displacement hydraulic pump B1 is simultaneously controlled to 0. Engaging clutch one C1 to engage gear three G3 with shaft one A1 in a relatively stationary state; by engaging the third clutch C3, the fifth gear G5 and the first shaft a1 are engaged in a relatively stationary state, and both smooth shifting and smooth speed change can be realized.

The first hydraulic motor M1 can drive the second shaft A2 to rotate through a seventh gear G7 and an eighth gear G8, and the second shaft A2 can also drive the first hydraulic motor M1 to serve as a large-displacement hydraulic pump to supply power to the second hydraulic motor M2. The fourth gear G4 can lock or release the first planet carrier X1, and change the transmission mode and the transmission ratio of the first planetary gear train; gear four G4 may also drive gear three G3 for floating rotation to effect engagement with shaft one a1 in a relatively stationary condition. Gear six G6 may drive gear five G5 for floating rotation to effect engagement with shaft one a1 in a relatively stationary condition. The two-planet gear train can work in a mode of fixing a planet carrier I X1, and also can work in a mode of fixing a sun gear I S1 and a sun gear II S2, so that multi-working-condition and large-range speed regulation of a shaft IV A4 is realized, and the complexity of large-range speed change transmission is reduced. Through the sectional combination of the gears, the torque is transmitted in an economical, efficient and compact relay mode according to the actual power output requirement.

As a further improvement of the utility model, a gear ten G10 is fixed on the shaft four A4, and the gear ten G10 is connected with the drive shaft transmission of the hydraulic motor two M2. The hydraulic pump B1 can provide power for the hydraulic motor II M2, the shaft II A2 can also drive the hydraulic motor I M1 to serve as a hydraulic pump to provide power for the hydraulic motor II M2, a gear nine G9 can be installed on a driving shaft of the hydraulic motor II M2, the gear nine G9 is meshed with a gear ten G10, the hydraulic motor II 2 drives the gear ten G10 to rotate through the gear nine G9, the gear ten G10 drives the shaft four A4 to rotate, the hydraulic motor II M2 can provide power for the shaft four A4, the shaft four A4 is accelerated together with power from two planetary gear trains, pure hydraulic power starting of parallel driving of the two hydraulic motors is achieved, and starting torque is large.

As a further improvement of the utility model, the gear seventeen G17 that is fixed on the three A3 shafts, the gear seventeen G17 meshes with the gear sixteen G16, the gear sixteen G16 meshes with the gear fifteen G15, and the gear fifteen G15 is connected with the one A1 shaft through the reverse gear clutch CR. The gear sixteen G16 can enable the rotation direction of the gear fifteen G15 during floating acceleration to be the same as that of the shaft one A1 and the shaft three A3, the gear fifteen G15 and the shaft one A1 can be combined in a relatively static state by combining the reverse clutch CR, and the gear fifteen G15 can provide reverse driving force for the inner ring gear two R2 through the shaft three A3.

As a further improvement of the utility model, the shaft four a4 is also provided with a gear eleventh G11, a synchronizer SY and a gear thirteenth G13, and the gear eleventh G11 or the gear thirteenth G13 is connected with the shaft four a4 through the synchronizer SY; the fifth parallel shaft system comprises a shaft five A5, a gear eighteen G18 for driving a differential is arranged at the output end of the shaft five A5, a gear twelve G12 and a gear fourteen G14 are fixedly arranged on the shaft five A5, the gear twelve G12 is meshed with the gear eleventh G11, and the gear fourteen G14 is meshed with the gear thirteen G13. The synchronizer SY is in a high-speed gear mode when combined with the gear eleven G11, is in a low-speed gear mode when combined with the gear thirteen G13, can realize the two-way switching of a high-speed gear and a low-speed gear by controlling the synchronizer SY through a manual selection button, enables forward and reverse to realize the two modes of the high-speed gear and the low-speed gear, and is suitable for a transportation mode and the low-speed gear is suitable for a field operation mode. And the switching of the high gear and the low gear does not influence the speed regulation mode, but the maximum speed value which can be reached by the vehicle is different.

Drawings

Fig. 1 is a transmission schematic diagram of the continuously variable transmission of the present invention.

Fig. 2 is a schematic diagram of the continuously variable transmission control system of the present invention.

Fig. 3 is a rotation speed relationship diagram of each basic member of the planetary gear train of the present invention.

Fig. 4 is a hydraulic flow diagram of the present invention working in the forward section i.

Fig. 5 is a diagram of the change of the rotation speed of each basic component of the planetary gear train when the utility model works in the forward I section.

Fig. 6 is a hydraulic flow diagram of the present invention working in the forward ii section.

Fig. 7 is a diagram of the change of the rotation speed of each basic component of the planetary gear train when the utility model works in the forward II section.

Fig. 8 is a hydraulic flow diagram of the present invention working in the forward iii section.

Fig. 9 is a diagram of the change of the rotation speed of each basic component of the planetary gear train when the planetary gear train works in the forward III section.

Fig. 10 is a hydraulic flow diagram of the present invention operating in forward iv section.

FIG. 11 is a diagram showing the variation of the rotation speed of each basic component of the planetary gear train when the present invention works in the forward IV stage.

Fig. 12 is a hydraulic flow diagram of the present invention when the present invention is operated in the backward stage i.

Fig. 13 is a diagram of the change of the rotation speed of each basic component of the planetary gear train when the planetary gear train works in the reverse stage i.

Fig. 14 is a hydraulic flow diagram of the present invention operating in the reverse ii section.

Fig. 15 is a diagram of the change of the rotation speed of each basic component of the planetary gear train when the utility model works in the backward stage ii.

Fig. 16 is a hydraulic flow diagram of the present invention operating in reverse iii.

Fig. 17 is a diagram of the change of the rotation speed of each basic component of the planetary gear train when the planetary gear train operates in the reverse iii stage.

In the figure: A1. a first shaft; A2. a second shaft; A3. a third shaft; A4. shaft four; A5. a fifth shaft; PTO and power takeoff; G1. a first gear; G2. a second gear; G3. a third gear; G4. a fourth gear; G5. a fifth gear; G6. a sixth gear; G7. a seventh gear; G8. eighth gear; G9. a ninth gear; G10. ten gears; G11. eleven gears; G12. a gear twelve; G13. thirteen gears; G14. fourteen gears; G15. fifteen gears; G16. sixteenth, a gear; G17. seventeen gears; G18. eighteen gears; C1. a first clutch; C2. a second clutch; C3. a third clutch; CR. reverse clutch; SY. a synchronizer; B1. a large displacement hydraulic pump; B2. a small displacement hydraulic pump; m1, a first hydraulic motor; m2, a second hydraulic motor; s1, a sun gear I; p1, a planet wheel I; x1. planet carrier I; r1, a first inner gear ring; s2, a sun gear II; p2, planet wheel II; x2. planet carrier II; r2, an inner gear ring II; y1 and Y2. are electro-hydraulic proportional valves I; y3. electro-hydraulic proportional valve II; y4. large-diameter electromagnetic change valve; K1. a first electromagnetic directional valve, a second K2. electromagnetic directional valve and a third K3. electromagnetic directional valve; K4. and a fourth electromagnetic directional valve.

Detailed Description

In the following description of the present invention, the terms "left", "right", "positive", "negative", etc. indicate the orientation, position or direction relationship based on the orientation or position relationship shown in the drawings, and are only for convenience of description and simplified description, and do not mean that the device must have a specific orientation or direction.

As shown in fig. 1, the continuously variable transmission in the present invention includes a transmission housing, a first shaft a1, a second shaft a2, a third shaft A3 and a fourth shaft a4 are installed in the transmission housing, the left end of the first shaft a1 is a power input end, a first gear G1, a first clutch C1, a second clutch C2, a third gear G3, a fifth gear G5 and a third clutch C3 are sequentially sleeved on the first shaft a1, the left end of the first shaft a1 can be connected with a flywheel of the engine, a first gear G1 is fixed on the first shaft a1 and meshed with a second gear G2, and a second gear G2 is installed on a driving shaft of a large displacement hydraulic pump B1; gear three G3 is connected to shaft one a1 through clutch one C1 or to the transmission housing through clutch two C2; gear five G5 is connected to shaft one A1 through clutch three C3. The right end of the first shaft a1 is connected to a power take-off which can take the maximum power of the engine to power other components of the vehicle.

The second shaft A2 is sequentially provided with an eight-G8 gear, a four-G4 gear, a first planetary gear train and a second planetary gear train, the eight-G8 gear is fixed on the second shaft A2 and is meshed with a seven-G7 gear, and the seven-G7 gear is arranged on a driving shaft of the first hydraulic motor M1; the first planetary gear train comprises a first sun gear S1, a first planet gear P1, a first planet carrier X1 and a first inner gear ring R1, the first planet carrier X1 is connected with a fourth gear G4 and is arranged on a second shaft A2 in a floating mode, and the fourth gear G4 is meshed with a third gear G3; the planetary gear train II comprises a sun gear II S2, a planet gear II P2, a planet carrier II X2 and an inner gear ring II R2, wherein the sun gear I S1 and the sun gear II S2 are both fixed on a shaft II A2, the inner gear ring I R1 is connected with the planet carrier II X2, and the center of the planet carrier II X2 is fixed at one end of the shaft II A4; the second ring gear R2 and the sixth gear G6 are fixed on the third shaft A3 together, the sixth gear G6 is meshed with the fifth gear G5, and the third shaft A3 is sleeved on the fourth shaft A4 in a floating mode and is coaxial.

The seventeen G17 fixed to the shaft three a3 meshes with the sixteen G16, the sixteen G16 meshes with the fifteen G15, and the fifteen G15 is connected to the shaft one a1 via the reverse clutch CR.

The gear ten G10 fixed to the shaft four a4 meshes with the gear nine G9, the gear nine G9 being mounted on the drive shaft of the hydraulic motor two M2. The shaft four A4 is also provided with an eleventh gear G11, a synchronizer SY and a thirteenth gear G13, and the eleventh gear G11 or the thirteenth gear G13 is connected with the shaft four A4 through the synchronizer SY; the fifth parallel shaft system comprises a shaft five A5, a gear eighteen G18 for driving a differential is arranged at the output end of the shaft five A5, a gear twelve G12 and a gear fourteen G14 are fixedly arranged on the shaft five A5, the gear twelve G12 is meshed with the gear eleventh G11, and the gear fourteen G14 is meshed with the gear thirteen G13. The synchronizer SY is in a high-speed gear mode when combined with the gear eleven G11, is in a low-speed gear mode when combined with the gear thirteen G13, can realize the two-way switching of a high-speed gear and a low-speed gear by controlling the synchronizer SY through a manual selection button, enables forward and reverse to realize the two modes of the high-speed gear and the low-speed gear, and is suitable for a transportation mode and the low-speed gear is suitable for a field operation mode. And the switching of the high gear and the low gear does not influence the speed regulation mode, but the maximum speed value which can be reached by the vehicle is different.

The first hydraulic motor M1 can drive the second shaft A2 to rotate through a seventh gear G7 and an eighth gear G8, and the second shaft A2 can also drive the first hydraulic motor M1 to serve as a large-displacement hydraulic pump to supply power to the second hydraulic motor M2. The fourth gear G4 can lock or release the first planet carrier X1, and change the transmission mode and the transmission ratio of the first planetary gear train; gear four G4 may also drive gear three G3 for floating rotation to effect engagement with shaft one a1 in a relatively stationary condition. Gear six G6 may drive gear five G5 for floating rotation to effect engagement with shaft one a1 in a relatively stationary condition. The two planetary gear trains can work in a mode of fixing a first planetary carrier X1, and also can work in a mode of fixing a first sun gear S1 and a second sun gear S2, so that multi-working-condition and large-range speed regulation of the shaft four A4 is realized.

As shown in fig. 2, the utility model discloses a continuously variable transmission control system, including big discharge capacity hydraulic pump B1, little discharge capacity hydraulic pump B2, hydraulic motor M1, hydraulic motor two M2, solenoid-operated valve K1, two K2 of solenoid-operated directional valve, three K3 of solenoid-operated directional valve and four K4 of solenoid-operated directional valve, one K1 of solenoid-operated directional valve, two K2 of solenoid-operated directional valve, three K3 of solenoid-operated directional valve and the P mouth of four K4 of solenoid-operated directional valve link to each other with the pressure oil pipe of little discharge capacity hydraulic pump B2 export respectively, the A mouth of one K1 of solenoid-operated directional valve links to each other with the control hydraulic fluid port of clutch C1, the A mouth of two K2 of solenoid-operated directional valve links to each other with the control of two C2 of clutch, the A mouth of three K3 of solenoid-operated directional valve links to each other with the control hydraulic port of three C3 of clutch, the A mouth of four K4 of solenoid-operated directional valve links; the large-displacement hydraulic pump B1 is controlled by the electro-hydraulic proportional valve I in displacement and flow direction and is connected with the hydraulic motor I M1 through a power oil supply pipe; the displacement of the hydraulic motor II M2 is controlled by an electro-hydraulic proportional valve II Y3, and the hydraulic motor II M2 is connected with the power oil supply pipe through a large-diameter electromagnetic directional valve Y4.

The rotation direction of the large-displacement hydraulic pump B1 is kept unchanged, and the flow direction of the power oil supply pipe is changed by electrifying the left coil Y1 or the right coil Y2 of the electro-hydraulic proportional valve I; the control system gives a PWM signal which starts to gradually increase from 0 to the left coil Y1 or the right coil Y2 of the electro-hydraulic proportional valve I, and the output displacement of the large-displacement hydraulic pump B1 is gradually increased from 0; the large-drift-diameter electromagnetic reversing valve Y4 is powered off and is positioned at a parallel conduction station; the large-drift-diameter electromagnetic directional valve Y4 is electrified and is positioned at a cross conduction station, so that the large-drift-diameter electromagnetic directional valve Y4 is conveniently matched with the electro-hydraulic proportional valve I and is matched with the working states of the hydraulic motor I M1 and the hydraulic motor II M2 together. The signal pressure oil output by the small displacement hydraulic pump B2 controls the disengagement or combination of the first clutch C1, the second clutch C2, the third clutch C3 and the reverse clutch CR respectively through the first electromagnetic directional valve K1, the second electromagnetic directional valve K2, the third electromagnetic directional valve K3 and the fourth electromagnetic directional valve K4.

As shown in fig. 3, the control method of the continuously variable transmission includes a forward mode including a forward i stage, a forward ii stage, a forward iii stage, and a forward iv stage, which are gradually increased in speed, in order, and a reverse mode including a reverse i stage, a reverse ii stage, and a reverse iii stage, which are gradually increased in speed, in order.

As shown in fig. 4 and 5, when advancing the segment i: the second electromagnetic directional valve K2 is electrified, the second clutch C2 is combined, and the first planet carrier X1 is kept static; the large-diameter electromagnetic reversing valve Y4 is in a power-off state and is in a parallel conduction station, the shaft I A1 drives the gear II G2 to rotate through the gear I G1, the control system gives a PWM signal which gradually increases from 0 to the left coil Y1 of the electro-hydraulic proportional valve I, the output displacement of the large-displacement hydraulic pump B1 is gradually increased from 0, the hydraulic motor I M1 and the hydraulic motor II M2 are driven to rotate, the hydraulic motor I M1 drives the shaft II A2 to rotate positively through the gear seven G7 and the gear eight G8 to drive the sun gear I S1 and the sun gear II S2 to rotate at the same speed and positively, the sun gear I S1 drives the ring gear I R1 to rotate reversely through the planet gear I P1, the ring gear I R1 drives the shaft IV A4 to rotate reversely through the planet carrier II X2, and the shaft IV A4V 5 rotates positively; the sun gear II S2 drives the inner gear ring II R2, the shaft III A3 and the gear VI G6 to float and rotate reversely through the planet gear II P2, the rotating speed is increased along with the floating, the gear VI G6 drives the gear V G5 to float and rotate forwardly, and when the advancing section I is finished, the rotating speed of the gear V G5 is the same as that of the shaft I A1; the second hydraulic motor M2 drives the four-A4 to rotate reversely through a nine-G9 gear and a ten-G10 gear, so that pure hydraulic power forward starting driven by the two hydraulic motors in parallel is realized, the forward starting torque is large, and the low-speed large torque is favorable for smooth starting of a vehicle on a heavy-load ramp. The shaft IV A4 drives the shaft V A5 to gradually increase from 0 speed, the hydraulic motor II M2 is in inverse proportion control, the control system gives a PWM signal which gradually increases from 0 to the electro-hydraulic proportional valve II Y3, the displacement of the hydraulic motor II M2 is reduced along with the reduction of the load, and the starting assisting force is gradually cancelled; when the output displacement of the large-displacement hydraulic pump B1 reaches the maximum value, namely the forward rotating speed of the shaft II A2 reaches the maximum value, the speed regulation of the forward I section is finished.

When the forward I section is switched to the forward II section: the electromagnetic directional valve III K3 is electrified, the clutch III C3 is combined, the gear V G5 is combined with the shaft I A1 in a relatively static state, and the gear V G5 drives the inner gear ring II R2 to keep rotating reversely; in order to realize zero-power backflow in the second forward section, a hydraulic system needs to be correspondingly switched, firstly, the large-path electromagnetic directional valve Y4 is electrified and is switched to a cross conduction station, namely, a connection oil path of the second hydraulic motor M2 is switched, so that the hydraulic output torque of the second hydraulic motor M2 is matched with the required torque direction of the shaft IV A4; then under the condition that the rotating speed of the first hydraulic motor M1 is kept unchanged, the displacement of the large-displacement hydraulic pump B1 is gradually reduced, the control system gives a PWM signal which is gradually reduced to the second electro-hydraulic proportional valve Y3 to increase the displacement of the second hydraulic motor M2, the first hydraulic motor M1 gradually takes the effect of the hydraulic pump until the displacement of the large-displacement hydraulic pump B1 is reduced to 0, and the hydraulic system is switched to be finished; in the switching process, the speed ratio of the transmission is kept unchanged without power interruption.

As shown in fig. 6 and 7, when advancing stage ii: when the second electromagnetic directional valve K2 is powered off, the second clutch C2 is disengaged, and the first planet carrier X1 is released from fixation; the electromagnetic directional valve III K3 is kept electrified to keep the clutch III C3 combined, and the speed of the shaft III A3 and the speed of the ring gear II R2 are kept unchanged and are used as the input end of the planetary gear train; the large-displacement hydraulic pump B1 keeps no displacement output, the first hydraulic motor M1 is used as a hydraulic pump, the control system gradually reduces the displacement of the second hydraulic motor M2, so that the first hydraulic motor M1 is decelerated, the second shaft A2, the first sun gear S1 and the second sun gear S2 are decelerated, the first inner gear R1, the second planet carrier X2 and the fourth shaft A4 are used as output ends of a planetary gear train to accelerate, and the fourth shaft A4 drives the fifth shaft A5 to accelerate. When the displacement of the second hydraulic motor M2 is reduced to 0, the first hydraulic motor M1 is in a hydraulically locked brake static state, the speeds of the second shaft A2, the first sun gear S1 and the second sun gear S2 are reduced to 0, the reverse rotation speed of the fourth shaft A4 is increased to a value at the end of the second forward segment, and the forward rotation speed of the fifth shaft A5 is increased to a value at the end of the second forward segment; planet carrier one X1 is in a floating reverse state and the speed follows the increase.

As shown in fig. 8 and 9, when advancing the stage iii: the electromagnetic directional valve III K3 is kept electrified to keep the clutch III C3 combined, the speed of the shaft III A3 and the speed of the ring gear II R2 are kept unchanged and still serve as the input end of the planetary gear train; the displacement of the second hydraulic motor M2 is reduced to 0, the displacement is not absorbed, and the torque is not output; the control system gives a PWM signal which starts from 0 to gradually increase a right coil Y2 of the electro-hydraulic proportional valve I, so that the output displacement of a large-displacement hydraulic pump B1 is gradually increased from 0, the flow direction is opposite to that of a forward section I, a hydraulic motor I M1 is driven to rotate in an accelerated mode gradually and the rotation direction is opposite to that of the forward section I, the hydraulic motor I M1 drives a second A2 to rotate in a reverse mode through a gear seven G7 and a gear eight G8, a first sun gear S1 and a second sun gear S2 are driven to rotate in the same speed and in the reverse mode, a second sun gear S2 drives a first inner gear ring R1, a second planet carrier X2 and a fourth shaft A4 to serve as output ends of a planetary gear train to accelerate, and a fourth shaft A4 drives; planet carrier one X1 is in a floating reverse state and the speed follows the increase. When the output displacement of the large-displacement hydraulic pump B1 reaches the maximum, the rotating speeds of the second shaft A2, the third shaft A3, the fourth shaft A4 and the first planet carrier X1 are equal, and the end point of the forward III section is reached.

When the forward III section is switched to the forward IV section: because the three A3 and the planet carrier one X1 and the gear four G4 rotate at the same speed, the gear three G3 and the shaft one A1 also rotate at the same speed, and the two are in relative static states; when the first electromagnetic directional valve K1 is electrified, the first clutch C1 is firstly combined, so that the third gear G3 is combined with the first shaft A1; in order to realize no power backflow in the forward IV section, a hydraulic system needs to be correspondingly switched, firstly, the large-path electromagnetic directional valve Y4 loses power and is switched to a parallel conduction station, namely, the connection oil circuit of the second hydraulic motor M2 is switched again, so that the hydraulic output torque of the second hydraulic motor M2 is matched with the required torque direction of the shaft IV A4; then under the condition that the rotating speed of the first hydraulic motor M1 is kept unchanged, the displacement of the large-displacement hydraulic pump B1 is gradually reduced, the displacement of the second hydraulic motor M2 is increased, the first hydraulic motor M1 gradually takes the role of the hydraulic pump until the displacement of the large-displacement hydraulic pump B1 is reduced to 0, and the hydraulic system is switched to be finished; in the switching process, the speed ratio of the transmission is kept unchanged without power interruption.

As shown in fig. 10 and 11, when advancing the iv stage: the electromagnetic directional valve III K3 loses power and the clutch III C3 is disengaged; the first electromagnetic directional valve K1 is kept electrified to keep the first clutch C1 combined, and the rotating speed of the first planet carrier X1 is kept unchanged and serves as the input end of the planetary gear train; the large-displacement hydraulic pump B1 keeps no displacement output, the first hydraulic motor M1 is used as a hydraulic pump, the displacement of the second hydraulic motor M2 is gradually reduced, the first hydraulic motor M1 is decelerated, the second shaft A2, the first sun gear S1 and the second sun gear S2 are decelerated, the first inner gear ring R1, the second planet carrier X2 and the fourth shaft A4 are used as the output ends of a planetary gear train to accelerate, and the fourth shaft A4 drives the fifth shaft A5 to accelerate; the ring gear II R2 and the shaft III A3 float and accelerate. When the displacement of the second hydraulic motor M2 is reduced to 0, the first hydraulic motor M1 is in a hydraulically locked brake static state, the speeds of the second shaft A2, the first sun gear S1 and the second sun gear S2 are reduced to 0, the reverse rotation speed of the fourth shaft A4 is increased to the maximum value of the forward IV section, the forward rotation speed of the fifth shaft A5 is increased to the maximum value of the forward IV section, and the speed regulation of the forward IV section is finished.

The process of the big reduction of the advancing speed is just opposite to the process of the small increase of the advancing speed, and the speed regulating process is reverse control and is not described any more.

In the parking mode: clutch two C2 is engaged, gear three G3, gear four G4 and carrier one X1 remain stationary; the output displacement of the large displacement hydraulic pump B1 is 0, the first hydraulic motor M1 and the second hydraulic motor M2 are both in a hydraulically locked braking standstill state, and the fourth shaft a4 and the fifth shaft a5 are both at standstill.

As shown in fig. 12 and 13, when the section i is reversed: the second electromagnetic directional valve K2 is electrified to enable the second clutch C2 to be combined, and the first planet carrier X1 is kept static; the large-drift-diameter electromagnetic reversing valve Y4 is in a power-off state and is in a parallel conduction station, the first shaft A1 drives the second gear G2 to rotate through the first gear G1, the control system gives a PWM signal which gradually increases from 0 to the right coil Y2 of the first electro-hydraulic proportional valve, the output displacement of the large-displacement hydraulic pump B1 is gradually increased from 0, the first hydraulic motor M1 and the second hydraulic motor M2 are driven to rotate, the first hydraulic motor M1 drives the second shaft A2 to rotate in the reverse direction through the seventh gear G7 and the eighth gear G8, the second shaft A2 serves as the input end of the planetary gear train to drive the first sun gear S1 and the second sun gear S2 to rotate in the same speed and in the reverse direction, the first sun gear S1 drives the first ring gear R1 to rotate in the forward direction through the first planet gear P1, the first ring gear R1 and the second planet carrier X2 serve as the output end of the planetary gear train to drive the fourth shaft A59; the sun gear II S2 drives the inner gear ring II R2, the shaft III A3 and the gear seventeen G17 to float and rotate forward through the planet gear II P2, the rotating speed is increased with the floating forward, the gear seventeen G17 drives the gear fifteen G15 to float and rotate forward through the gear sixteen G16, and when the section I of the reverse motion is finished, the speed of the gear fifteen G15 is the same as that of the shaft I1; the second hydraulic motor M2 drives the shaft four A4 to rotate in the positive direction through the gear nine G9 and the gear ten G10, pure hydraulic power reverse starting driven by the double hydraulic motors in parallel is achieved, the reverse starting torque is large, the shaft four A4 drives the shaft five A5 to increase from 0 speed, the control system gives a PWM signal to the electro-hydraulic proportional valve two Y3, the PWM signal increases from 0 speed, the displacement of the second hydraulic motor M2 is reduced along with the reduction of the load, and the starting assisting force is cancelled gradually; when the output displacement of the large-displacement hydraulic pump B1 reaches the maximum value, namely the reverse rotation speed of the shaft two A2 reaches the maximum value, the speed regulation of the reverse I section is finished.

When the backward I section is switched to the backward II section: the electromagnetic directional valve IV K4 is electrified, the reverse clutch CR is combined, the gear fifteen G15 and the shaft I A1 are combined in a relatively static state, and the gear fifteen G15 drives the inner gear ring II R2 to keep forward rotation; in order to reverse the non-power backflow in the second section, the hydraulic system needs to be correspondingly switched, firstly, the large-path electromagnetic directional valve Y4 is electrified and is switched to a cross conduction station, namely, a connection oil circuit of the second hydraulic motor M2 is switched, so that the hydraulic output torque of the second hydraulic motor M2 is matched with the required torque direction of the shaft IV A4; then under the condition that the rotating speed of the first hydraulic motor M1 is kept unchanged, the displacement of the large-displacement hydraulic pump B1 is gradually reduced, the displacement of the second hydraulic motor M2 is increased, the first hydraulic motor M1 gradually takes the role of the hydraulic pump until the displacement of the large-displacement hydraulic pump B1 is reduced to 0, and the hydraulic system is switched to be finished; in the switching process, the speed ratio of the transmission is kept unchanged without power interruption.

As shown in fig. 14 and 15, when the second stage is reversed: when the second electromagnetic directional valve K2 is powered off, the second clutch C2 is disengaged, and the first planet carrier X1 is released from fixation; the electromagnetic directional valve IV K4 is kept electrified, so that the reverse clutch CR is kept combined, and the speed of the shaft III A3 and the speed of the ring gear II R2 are kept unchanged and are used as the input end of the planetary gear train; the large-displacement hydraulic pump B1 keeps no displacement output, the first hydraulic motor M1 is used as a hydraulic pump, the displacement of the second hydraulic motor M2 is gradually reduced, the first hydraulic motor M1 is decelerated, the second shaft A2, the first sun gear S1 and the second sun gear S2 are decelerated, the first inner gear ring R1, the second planet carrier X2 and the fourth shaft A4 are used as the output ends of a planetary gear train to accelerate, and the fourth shaft A4 drives the fifth shaft A5 to accelerate; when the displacement of the second hydraulic motor M2 is reduced to 0, the first hydraulic motor M1 is in a hydraulically locked brake static state, the speeds of the second shaft a2, the first sun gear S1 and the second sun gear S2 are reduced to 0, the forward speed of the fourth shaft a4 is increased to a value at the end of the reverse ii phase, and the reverse speed of the fifth shaft a5 is increased to a value at the end of the reverse ii phase; planet carrier one X1 is in a floating forward state, with the speed following the increase.

As shown in fig. 16 and 17, when the section iii is reversed: the electromagnetic directional valve IV K4 is kept electrified, so that the reverse clutch CR is kept combined, and the speed of the shaft III A3 and the speed of the ring gear II R2 are kept unchanged and still serve as the input end of the planetary gear train; the displacement of the second hydraulic motor M2 is reduced to 0, the displacement is not absorbed, and the torque is not output; the large-drift-diameter electromagnetic reversing valve Y4 is powered off and is switched to a parallel conduction station; the control system gives a PWM signal which starts from 0 to gradually increase a left coil Y1 of the electro-hydraulic proportional valve I, so that the output displacement of a large-displacement hydraulic pump B1 is gradually increased from 0, the flow direction is opposite to that of a reverse I section, a hydraulic motor I M1 is driven to rotate in an accelerated mode gradually and the rotation direction is opposite to that of the reverse I section, the hydraulic motor I M1 drives a sun gear I S1 and a sun gear II S2 to rotate in a forward direction through a gear seven G7 and a gear eight G8, the sun gear II S2 drives a planet carrier II X2, a ring gear I R1 and a shaft four A4 to rotate in the same speed in the forward direction, the planet carrier II X2, the ring gear I R1 and a shaft four A4 are used as output ends of a planetary gear train; the planet carrier I1 is in a floating forward rotation state, and the speed is increased along with the increase; when the output displacement of the large-displacement hydraulic pump B1 reaches the maximum, the rotating speeds of the second shaft A2, the third shaft A3, the fourth shaft A4 and the first planet carrier X1 are equal, and the end point of the reverse III section is reached.

The process of the reverse speed from large reduction to small increase is just opposite, and the speed regulation process is reverse control and is not described in detail.

The utility model discloses a buncher control system can realize that clutch joint portion combines under the constant speed state, and adjacent speed section trades the section under the constant speed state, and the speed governing is controllable in succession, and the nature controlled is good, and the reliability is high. The torque and speed regulation range of the stepless speed changer are large, the whole course power is switched uninterruptedly, and the speed-change clutch without differential speed is a constant speed state switching section. The forward and the backward can be directly switched under the state of no stopping, and the controllability is high. And the parking without flameout on the ramp can be realized without starting the parking brake. The utility model adopts the double hydraulic motors to drive, so that the specification of the hydraulic element is reduced, and the purchase and the cost control are convenient; the transmission has compact structure and small volume, and is convenient for complete machine matching and optimized arrangement.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention. In addition to the above embodiments, the present invention can also have other embodiments, for example, "left", "right" and "positive" and "negative" can be interchanged. All the technical solutions formed by adopting equivalent substitutions or equivalent transformations fall within the protection scope claimed by the present invention. The undescribed technical features of the present invention can be realized by or using the prior art, and are not described herein again.

Claims

1. A continuously variable transmission control system comprising a large displacement hydraulic pump (B1), a small displacement hydraulic pump (B2), a first hydraulic motor (M1), a second hydraulic motor (M2), a first electromagnetic directional valve (K1), a second electromagnetic directional valve (K2), a third electromagnetic directional valve (K3), and a fourth electromagnetic directional valve (K4), characterized in that: p ports of a first electromagnetic directional valve (K1), a second electromagnetic directional valve (K2), a third electromagnetic directional valve (K3) and a fourth electromagnetic directional valve (K4) are respectively connected with a pressure oil pipe at the outlet of a small-displacement hydraulic pump (B2), an A port of the first electromagnetic directional valve (K1) is connected with a control oil port of a first clutch (C1), an A port of the second electromagnetic directional valve (K2) is connected with a control oil port of a second clutch (C2), an A port of the third electromagnetic directional valve (K3) is connected with a control oil port of the third clutch (C3), and an A port of the fourth electromagnetic directional valve (K4) is connected with a control oil port of a reverse Clutch (CR); the large-displacement hydraulic pump (B1) is controlled by the electro-hydraulic proportional valve I in displacement and flow direction and is connected with the hydraulic motor I (M1) through a power oil supply pipe; and the second hydraulic motor (M2) is controlled by the second electro-hydraulic proportional valve (Y3) to control the displacement thereof and is connected with the power oil supply pipe through a large-diameter electromagnetic directional valve (Y4).

2. The cvt control system according to claim 1, characterized in that the first clutch (C1), the second clutch (C2), the third clutch (C3) and the reverse Clutch (CR) are all fitted on the first shaft (a1) of the transmission, the first shaft (a1) is also mounted with the first gear (G1), the third gear (G3), the fifth gear (G5) and the fifteenth gear (G15), the first gear (G1) is fixed on the first shaft (a1) and drives the large displacement hydraulic pump (B1) through the second gear (G2); gear three (G3) is connected to shaft one (a1) via clutch one (C1) or to the transmission housing via clutch two (C2); gear five (G5) is connected to shaft one (a1) through clutch three (C3), and gear fifteen (G15) is connected to shaft one (a1) through reverse Clutch (CR); a second shaft (A2) of the transmission is sequentially provided with a eighth gear (G8), a fourth gear (G4), a first planetary gear train and a second planetary gear train, wherein the eighth gear (G8) is fixed on the second shaft (A2) and is meshed with a seventh gear (G7), and the seventh gear (G7) is arranged on a driving shaft of a first hydraulic motor (M1); the planetary gear train I comprises a sun gear I (S1), a planet gear I (P1), a planet carrier I (X1) and an inner gear I (R1), the planet carrier I (X1) is connected with a gear II (G4) and is installed on a shaft II (A2) in a floating mode, and the gear IV (G4) is meshed with the gear III (G3); the planetary gear train II comprises a sun gear II (S2), a planet gear II (P2), a planet carrier II (X2) and an inner gear ring II (R2), wherein the sun gear I (S1) and the sun gear II (S2) are both fixed on a shaft II (A2), the inner gear ring I (R1) is connected with the planet carrier II (X2), and the center of the planet carrier II (X2) is fixed at one end of a shaft IV (A4); the inner gear ring II (R2) and the gear six (G6) are fixed on the shaft III (A3) together, the gear six (G6) is meshed with the gear five (G5), and the shaft III (A3) is sleeved on the shaft IV (A4) in a floating mode and is coaxial.

3. The cvt control system according to claim 2, characterized in that a gear ten (G10) is fixed to the shaft four (a4), the gear ten (G10) being in driving connection with the drive shaft of the hydraulic motor two (M2).

4. The cvt control system according to claim 3, wherein a seventeen (G17) gear is fixed to shaft three (a3), a seventeen (G17) gear meshes with a sixteenth (G16) gear, and a sixteenth (G16) gear meshes with a fifteenth (G15) gear.

5. Continuously variable transmission control system according to claim 3, characterized in that shaft four (A4) is further fitted with gear eleven (G11), Synchronizer (SY) and gear thirteen (G13), and gear eleven (G11) or gear thirteen (G13) is connected to shaft four (A4) through Synchronizer (SY); the fifth parallel shaft system comprises a fifth shaft (A5), an eighteen gear (G18) for driving a differential is installed at the output end of the fifth shaft (A5), a twelfth gear (G12) and a fourteenth gear (G14) are fixedly installed on the fifth shaft (A5), the twelfth gear (G12) is meshed with the eleventh gear (G11), and the fourteenth gear (G14) is meshed with the thirteenth gear (G13).