Search

CN-224214465-U - Tractor HST hydraulic control system

CN224214465UCN 224214465 UCN224214465 UCN 224214465UCN-224214465-U

Abstract

The HST hydraulic control system of the tractor comprises a hydraulic pump and a hydraulic motor, wherein the hydraulic pump and the hydraulic motor are connected with a low-pressure oil way through a high-pressure oil way which is connected in parallel, an oil supplementing oil way is connected to the hydraulic pump, a first slide valve and a second slide valve are connected in parallel to the oil supplementing oil way, an oil inlet of the first slide valve is connected with a variable piston bottom oil cavity of the hydraulic pump, and an oil inlet of the second slide valve is connected with a variable piston top oil cavity of the hydraulic pump. The utility model solves the problems of poor fuel economy caused by the defects of poor comfort, complex operation and power waste of the hydraulic control circuit in the traditional technology.

Inventors

  • YANG XU
  • LI YANGUO
  • JIN XINGLEI
  • YUE XIAOKAI

Assignees

  • 泰安泰山国泰拖拉机制造有限公司

Dates

Publication Date
20260508
Application Date
20250628

Claims (9)

  1. 1. The HST hydraulic control system of the tractor is characterized by comprising a hydraulic pump (1) and a hydraulic motor (2), wherein a high-pressure oil way (3) connected in parallel is connected with a low-pressure oil way (4) between the hydraulic pump (1) and the hydraulic motor (2), an oil supplementing oil way (8) is connected to the hydraulic pump (1), a first slide valve (6) and a second slide valve (7) are connected in parallel to the oil supplementing oil way (8), an oil inlet of the first slide valve (6) is connected with a variable piston bottom oil cavity of the hydraulic pump (1), and an oil inlet of the second slide valve (7) is connected with a variable piston top oil cavity of the hydraulic pump (1).
  2. 2. The tractor HST hydraulic control system according to claim 1, wherein the oil supplementing oil way (8) is connected with a throttle valve (10).
  3. 3. The HST hydraulic control system of the tractor according to claim 1 is characterized in that an oil supplementing overflow valve (9) is connected in parallel to the oil supplementing oil way (8).
  4. 4. The HST hydraulic control system of the tractor according to claim 3 is characterized in that the high-pressure oil way (3) and the low-pressure oil way (4) are respectively connected with a system overflow valve (5) in parallel, and the outlet ends of the two system overflow valves (5) are connected with the oil supplementing overflow valve (9).
  5. 5. The HST hydraulic control system of the tractor according to claim 1, wherein hydraulic motor (2) is provided with hydraulic motor detection oil ports (12) at positions on two sides of the high-pressure oil path (3) and the low-pressure oil path (4) respectively.
  6. 6. The tractor HST hydraulic control system according to claim 1 is characterized in that hydraulic pump detection oil ports (13) are respectively arranged at two end positions of a variable piston of the hydraulic pump (1).
  7. 7. The tractor HST hydraulic control system according to claim 1, wherein the first spool valve (6) and the second spool valve (7) comprise two-position three-way valves.
  8. 8. The HST hydraulic control system of the tractor according to claim 3, wherein the outlet end of the oil supplementing overflow valve (9) is connected with an oil tank (11).
  9. 9. The tractor HST hydraulic control system according to claim 1, wherein the oil outlets of the first slide valve (6) and the second slide valve (7) are connected with an oil tank (11).

Description

Tractor HST hydraulic control system Technical Field The utility model relates to the technical field of hydraulic control systems, in particular to a tractor HST hydraulic control system. Background The HST system is a hydraulic driving walking system of the tractor, and the hydraulic pump is used for conveying pressure oil to a hydraulic motor, and the hydraulic motor drives wheels to walk. The forward rotation and the reverse rotation of the hydraulic pump determine the output direction of pressure oil of the hydraulic pump, and further determine the rotation direction of an output shaft of the hydraulic motor, so that the walking and the reversing of the tractor are realized. Along with the expansion of the application field of the tractor, a user has higher requirements on the speed control of the whole machine, so that the speed continuity control is realized, and the operation is more convenient and comfortable. The prior art discloses a patent with the publication number CN222277062U, which comprises an oil supplementing pump, a traveling pump and a traveling motor, wherein the traveling pump and the traveling motor form loop connection through a pipeline, an oil supplementing shunt and a control shunt are arranged at an outlet of the oil supplementing pump, the oil supplementing shunt is respectively connected with a first one-way valve and a second one-way valve through the shunt, an outlet of the first one-way valve is connected with one end of the traveling motor, an outlet of the second one-way valve is connected with the other end of the traveling motor, the control shunt is connected with an electromagnetic reversing valve, the electromagnetic reversing valve is connected with a plunger mechanism, and an output end of the plunger mechanism is connected with a control switch of the traveling pump. The utility model can control the output end of the plunger mechanism to move continuously by the oil supplementing pump supplying oil to the control branch circuit and the electromagnetic reversing valve controlling the oil output direction, and control the control switch of the traveling pump, thereby realizing the advancing and retreating state control and the speed continuous control of the HST system and improving the operation convenience. The prior device gradually exposes the defects of the technology along with the use, and the prior device mainly comprises the following aspects: The existing hydraulic control loop has the defects of poor comfort, complex operation, power waste, poor fuel economy and the like. In summary, it is clear that the prior art has inconvenience and defects in practical use, so that improvement is needed. Disclosure of utility model Aiming at the defects in the prior art, the utility model solves the problems of poor fuel economy caused by the defects of poor comfort, complex operation and power waste of the hydraulic control circuit in the traditional technology. In order to solve the problems, the utility model provides the following technical scheme: The HST hydraulic control system of the tractor comprises a hydraulic pump and a hydraulic motor, wherein the hydraulic pump and the hydraulic motor are connected with a low-pressure oil way through a high-pressure oil way which is connected in parallel, an oil supplementing oil way is connected to the hydraulic pump, a first slide valve and a second slide valve are connected in parallel to the oil supplementing oil way, an oil inlet of the first slide valve is connected with a variable piston bottom oil cavity of the hydraulic pump, and an oil inlet of the second slide valve is connected with a variable piston top oil cavity of the hydraulic pump. As an optimized scheme, a throttle valve is connected to the oil supplementing oil circuit. As an optimized scheme, the oil supplementing oil circuit is connected with an oil supplementing overflow valve in parallel. As an optimized scheme, the high-pressure oil way and the low-pressure oil way are respectively connected with a system overflow valve in parallel, and the outlet ends of the two system overflow valves are connected with the oil supplementing overflow valve. As an optimized scheme, the positions of the hydraulic motor at the two sides of the high-pressure oil way and the low-pressure oil way are respectively provided with a hydraulic motor detection oil port. As an optimized scheme, hydraulic pump detection oil ports are respectively arranged at two end positions of a variable piston of the hydraulic pump. As an optimized scheme, the first slide valve and the second slide valve comprise two-position three-way valves. As an optimized scheme, the outlet end of the oil supplementing overflow valve is connected with an oil tank. As an optimized scheme, the oil outlets of the first slide valve and the second slide valve are connected with an oil tank. Compared with the prior art, the utility model has the beneficial effects that: The hydraulic pump is directly power