CN117345708A - A speed-adjustable harvester hydraulic system - Google Patents
A speed-adjustable harvester hydraulic system Download PDFInfo
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- CN117345708A CN117345708A CN202310687536.4A CN202310687536A CN117345708A CN 117345708 A CN117345708 A CN 117345708A CN 202310687536 A CN202310687536 A CN 202310687536A CN 117345708 A CN117345708 A CN 117345708A
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- valve
- hydraulic
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- hydraulic system
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Classifications
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- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01D—HARVESTING; MOWING
- A01D69/00—Driving mechanisms or parts thereof for harvesters or mowers
- A01D69/03—Driving mechanisms or parts thereof for harvesters or mowers fluid
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- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01D—HARVESTING; MOWING
- A01D69/00—Driving mechanisms or parts thereof for harvesters or mowers
- A01D69/10—Brakes
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/06—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with two or more servomotors
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental Sciences (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
一种可调速的收割机液压系统，包括油泵、油箱、电液比例阀、比例溢流阀、液压执行回路，油泵的进油口与油箱相连，出油口与电液比例阀相连；电液比例阀的出油口与执行回路的第一端相连，用于调节液压执行回路的流量、压力大小从而对液压驱动元件进行调速；比例溢流阀的进油口与油泵出油口相连，出油口与回油路相连，用于控制液压执行回路的压力；在本液压系统的回油主路上设置比例溢流阀为液压系统提供回油背压压力，实现给液压执行元件提供惯性运动的阻力，使得液压执行元件换向、或者回到中位时尽快停止动作，达到快速平稳刹车。
A speed-adjustable harvester hydraulic system includes an oil pump, an oil tank, an electro-hydraulic proportional valve, a proportional relief valve, and a hydraulic execution circuit. The oil inlet of the oil pump is connected to the oil tank, and the oil outlet is connected to the electro-hydraulic proportional valve; the electric The oil outlet of the hydraulic proportional valve is connected to the first end of the execution circuit, which is used to adjust the flow and pressure of the hydraulic execution circuit to regulate the speed of the hydraulic drive components; the oil inlet of the proportional relief valve is connected to the oil outlet of the oil pump. , the oil outlet is connected to the oil return line and is used to control the pressure of the hydraulic actuator circuit; a proportional relief valve is set on the main oil return line of the hydraulic system to provide oil return back pressure for the hydraulic system to provide inertia for the hydraulic actuator. The resistance to movement causes the hydraulic actuator to stop moving as quickly as possible when it changes direction or returns to the neutral position, achieving fast and smooth braking.
Description
Technical Field
The invention belongs to the technical field of harvester hydraulic pressure, and particularly relates to a speed-adjustable harvester hydraulic system.
Background
At present, a hydraulic system of the harvester mainly adopts a mechanical operation mode, so that lifting of a cutting table of the harvester, turning in and out of a grain discharging cylinder, lifting of a reel, combination and separation of a main clutch, forward and reverse blowing of a fan and the like can be realized, but the speed of the hydraulic system of the harvester is regulated mechanically, the flexibility and reliability of the mechanical operation mode are poor, the user experience is poor, and when an agricultural machine meets the terrain change and needs to quickly regulate the height of the cutting table, the conventional hydraulic system cannot meet the requirement. The patent number is: 2016107729844, the name is: a hydraulic system of a harvester utilizes a flow dividing valve to divide an oil way into a first control oil way and a second control oil way, wherein the first control oil way is connected in series with an electromagnetic directional valve I for controlling a gun barrel motor and a steering manual directional valve for controlling a steering oil cylinder, the second control oil way is connected in series with a cutting table manual directional valve for controlling a cutting table oil cylinder, an electromagnetic directional valve II for controlling a reel oil cylinder and an electromagnetic directional valve III for controlling a grain unloading oil cylinder, and the hydraulic system of the harvester realizes the combination of electric control and mechanical control but cannot realize the speed regulation of the hydraulic system.
Disclosure of Invention
The invention provides a harvester hydraulic system capable of adjusting speed aiming at the problems in the prior art, and solves the technical problem of realizing speed adjustment of an executive component of the hydraulic system.
Specifically, the harvester hydraulic system with adjustable speed comprises an oil pump, an oil tank, an electrohydraulic proportional valve, a proportional overflow valve and a hydraulic execution loop, wherein an oil inlet of the oil pump is connected with the oil tank, and an oil outlet of the oil pump is connected with the electrohydraulic proportional valve;
the oil outlet of the electro-hydraulic proportional valve is connected with the first end of the execution loop and is used for adjusting the flow and the pressure of the hydraulic execution loop, and the electro-hydraulic proportional valve continuously and proportionally controls the oil flow and the pressure of a hydraulic system along with an input electric signal so as to speed-regulate a hydraulic driving element;
the oil inlet of the proportional overflow valve is connected with the oil outlet of the oil pump, the oil outlet is connected with the oil return path, the proportional overflow valve is used for controlling the pressure of the hydraulic execution loop, and the proportional overflow valve is arranged on the oil return main path of the hydraulic system to provide oil return back pressure for the hydraulic system, namely, the resistance of inertial movement for the hydraulic execution element is realized, so that the hydraulic execution element can stop acting as soon as possible when reversing or returning to the middle position, and the purpose of rapid and stable braking is achieved; the electro-hydraulic proportional valve and the proportional overflow valve synchronously regulate the flow and the pressure of the hydraulic execution circuit, so that the flow and the pressure required by the execution circuit are ensured; and the second end of the hydraulic execution loop is connected with the oil return loop.
The execution loop comprises a hydraulic execution element and an electromagnetic valve; the execution loop comprises a second branch, a third branch, a fourth branch, a fifth branch, a sixth branch, a seventh branch and an eighth branch which are connected in parallel; the second branch is used for controlling the lifting of the harvester cutting table; the third branch is used for controlling the rotation in and out of the grain unloading cylinder; the fourth branch is used for controlling the lifting of the grain unloading cylinder; the fifth branch is used for controlling the lifting of the reel; the sixth branch is used for controlling the combination and the separation of the main clutch; the seventh branch is used for controlling the rising speed and the falling speed of the roller; the eighth branch is used for controlling the positive and negative blowing of the fan;
the hydraulic actuating element of the actuating loop comprises a header oil cylinder, a grain discharging cylinder motor, a grain discharging cylinder oil cylinder, a reel oil cylinder, a main clutch motor, a roller motor and a fan motor, and the electromagnetic valve is a three-position four-way electromagnetic valve.
Further, a back pressure valve is arranged between the hydraulic actuating element of the second actuating loop and the electromagnetic valve, an oil outlet of the back pressure valve is connected with the oil return path, and the back pressure valve is used for keeping the hydraulic pressure of the hydraulic actuating element stable and preventing the cutting table from descending.
Furthermore, the electromagnetic valve can also be a multi-way valve arranged on the same valve group, and the valve blocks of the multi-way valve comprise a header valve block, a grain cylinder rotating valve block, a grain cylinder lifting valve block, a reel valve block, a main clutch valve block, a roller valve block and a fan valve block, and all the valve blocks are connected in parallel and fixed on the multi-way valve.
Drawings
Fig. 1 is a schematic diagram of a speed adjustable harvester hydraulic system.
Detailed Description
The invention will be further described with reference to the accompanying drawings and detailed description, wherein the drawings are only schematic designs of hydraulic systems; any combination of the various embodiments or features described below may be implemented to form new embodiments without conflict. Furthermore, the terms first leg, second leg, and the like in the description and in the claims of the present application are not used for any order, quantity, or importance. The terms "mounted," "connected," "secured," and the like in the present application are to be construed broadly.
Referring to fig. 1, in the speed-adjustable harvester hydraulic system, a main path 1 of the hydraulic system is provided with an oil inlet end, a T end is provided with an oil return end, the P end is connected with the oil inlet ends of all execution loops through electro-hydraulic proportional valves 2, namely, the oil inlet end P of the main path 1 of the hydraulic system is connected with electro-hydraulic proportional valves V2, and oil outlets of the electro-hydraulic proportional valves are connected with a first end of each execution loop. The hydraulic system comprises an oil pump (not illustrated), an oil tank (not illustrated), an electro-hydraulic proportional valve V2, a proportional overflow valve V1 and a hydraulic execution loop; an oil inlet of the oil pump is connected with an oil tank, and an oil outlet of the oil pump is connected with an electrohydraulic proportional valve V2 through an oil pipe; the oil inlet end P and the oil return end T of the main circuit 1 of the hydraulic system are connected with a proportional relief valve V1, and the proportional relief valve V1 is used for controlling the pressure of the hydraulic execution circuit and providing oil return back pressure for the hydraulic system.
The execution loop comprises a second branch 2, a third branch 3, a fourth branch 4, a fifth branch 5, a sixth branch 6, a seventh branch 7 and an eighth branch 8 which are connected in parallel; the second branch is used for controlling the lifting of the harvester cutting table; the third branch is used for controlling the rotation in and out of the grain unloading cylinder; the fourth branch is used for controlling the lifting of the grain unloading cylinder; the fifth branch is used for controlling the lifting of the reel; the sixth branch is used for controlling the combination and the separation of the main clutch; the seventh branch is used for controlling the rising speed and the falling speed of the roller; the eighth branch is used for controlling the positive and negative blowing of the fan; the hydraulic execution loop further comprises an electromagnetic valve, and the electromagnetic valve is a three-position four-way electromagnetic valve. The first end of the hydraulic execution return is communicated with the oil inlet end P of the electromagnetic valve, and the oil outlet end T of the electromagnetic valve is communicated with the oil return channel.
The hydraulic actuating element of the actuating loop comprises a header oil cylinder, a grain discharging cylinder motor, a grain discharging cylinder oil cylinder, a reel oil cylinder, a main clutch motor, a roller motor and a fan motor, and the electromagnetic valve is a three-position four-way electromagnetic valve. And a back pressure valve is arranged between the hydraulic actuating element of the second actuating loop and the electromagnetic valve, an oil outlet of the back pressure valve is connected with the oil return path, the rated pressure of the back pressure valve of the header oil cylinder is 9MPa under the normal condition, and the back pressure valve is used for keeping the hydraulic pressure of the hydraulic actuating element stable and preventing the header from descending.
The oil outlet of the electrohydraulic proportional valve V2 is connected with the first end of the execution loop and is used for adjusting the flow and the pressure of the hydraulic execution loop, and the electrohydraulic proportional valve continuously and proportionally controls the flow and the pressure of a liquid flow of a hydraulic system along with an input electric signal so as to speed-regulate a hydraulic driving element; the proportional overflow valve V1 is used for controlling the pressure of the hydraulic execution loop, and the proportional overflow valve V1 is arranged on the oil return main path of the hydraulic system to provide oil return back pressure for the hydraulic system, namely, the resistance of inertial movement for the hydraulic execution element is realized, so that the hydraulic execution element stops acting as soon as possible when reversing or returning to the middle position, and the purpose of rapid and stable braking is achieved; the electro-hydraulic proportional valve and the proportional overflow valve synchronously regulate the flow and the pressure of the hydraulic execution circuit, so that the flow and the pressure required by the execution circuit are ensured.
Specifically, in the second branch, the header oil cylinder is connected with a three-position four-way electromagnetic valve, the header is lifted, the left position of the electromagnetic valve is powered by the oil cylinder to lift the header, the right position is powered by the oil cylinder to shrink the header to descend, the oil cylinder is not moved when the electromagnetic valve is in the middle position, the header is kept in situ, the back pressure valve keeps the pressure of the hydraulic oil cylinder stable, the header is prevented from descending, the lifting and descending speed of the header is accelerated or decelerated after the speed regulation of the electro-hydraulic proportional valve, and the proportional overflow valve generates back pressure during speed regulation or reversing, so that the stability of a moving part is increased. In the third branch, the grain discharging motor is connected with a three-position four-way electromagnetic valve, hydraulic energy is converted into torque and rotating speed of a shaft, a grain discharging cylinder positively rotated by an electric motor on the left side of the electromagnetic valve rotates out of a bracket, a grain discharging cylinder reversely rotated by the electric motor on the right side of the electromagnetic valve rotates in the middle position, the motor stops rotating when the electromagnetic valve is positioned in the middle position, the rotating speed of the motor is changed after the speed of the electromagnetic valve is regulated by an electro-hydraulic proportional valve, and the rotating speed of the grain discharging cylinder is changed; in the fourth branch, the grain discharging cylinder oil cylinder is connected with a three-position four-way electromagnetic valve to finish the lifting, the falling and the holding of the grain discharging cylinder; in the fifth branch, the reel oil cylinder is connected with a three-position four-way electromagnetic valve to finish the lifting, lowering and keeping the reel in situ; in the sixth branch, the main clutch motor is connected with a three-position four-way electromagnetic valve to complete the combination and separation of the main clutch; in the seventh branch, the roller motor is connected with a three-position four-way electromagnetic valve, and acceleration and deceleration of the roller are completed under the regulation action of a proportional electromagnetic valve; in the eighth branch, the fan motor is connected with a three-position four-way electromagnetic valve to finish forward blowing and backward blowing of the fan; the speed regulation function of the electro-hydraulic proportional valve and the proportional overflow valve in the third branch, the fourth branch, the fifth branch, the sixth branch, the seventh branch and the eighth branch control the pressure of the hydraulic execution loop, and the function of providing the back pressure of the oil return is the same and is not repeated in the next step.
In another embodiment of the present invention, on the basis of the above embodiment, the solenoid valve may be a multiple-way valve installed on the same valve block, and the valve blocks of the multiple-way valve include a header valve block, a grain cylinder rotating valve block, a grain cylinder lifting valve block, a reel valve block, a main clutch valve block, a roller valve block, and a fan valve block, where each valve block is fixed on the multiple-way valve in parallel.
An electro-hydraulic proportional valve is arranged on a main circuit of the hydraulic system, an oil outlet of the electro-hydraulic proportional valve is connected with a first end of an execution loop and is used for adjusting the flow and the pressure of the hydraulic execution loop so as to regulate the speed of a hydraulic driving element; the oil return main circuit of the hydraulic system is provided with the proportional overflow valve, the oil inlet of the proportional overflow valve is connected with the oil outlet of the oil pump, the oil outlet is connected with the oil return circuit and used for controlling the pressure of the hydraulic execution circuit and providing oil return back pressure for the hydraulic system, so that the resistance of inertial movement is provided for the hydraulic execution element, the hydraulic execution element can be stopped to act as soon as possible when reversing or returning to the middle position, and the rapid and stable braking is achieved.
Claims (7)
1. The utility model provides a harvester hydraulic system of adjustable speed, includes oil pump, oil tank, electrohydraulic proportional valve, proportion overflow valve, hydraulic pressure execution circuit, its characterized in that:
an oil inlet of the oil pump is connected with an oil tank, and an oil outlet of the oil pump is connected with an electrohydraulic proportional valve;
the oil outlet of the electro-hydraulic proportional valve is connected with the first end of the execution loop and is used for adjusting the flow and the pressure of the hydraulic execution loop so as to speed the hydraulic driving element;
the oil inlet of the proportional overflow valve is connected with the oil outlet of the oil pump, the oil outlet is connected with the oil return path, and the proportional overflow valve is used for controlling the pressure of the hydraulic execution loop and providing oil return back pressure for the hydraulic system;
the electro-hydraulic proportional valve and the proportional overflow valve synchronously regulate the flow and the pressure of the hydraulic execution circuit, so that the flow and the pressure required by the execution circuit are ensured;
and the second end of the hydraulic execution loop is connected with the oil return loop.
2. The adjustable speed harvester hydraulic system of claim 1 wherein: the execution loop consists of a hydraulic execution element and an electromagnetic valve; the execution loop comprises a second branch, a third branch, a fourth branch, a fifth branch, a sixth branch, a seventh branch and an eighth branch which are connected in parallel;
the second branch is used for controlling the lifting of the harvester cutting table;
the third branch is used for controlling the rotation in and out of the grain unloading cylinder;
the fourth branch is used for controlling the lifting of the grain unloading cylinder;
the fifth branch is used for controlling the lifting of the reel;
the sixth branch is used for controlling the combination and separation of the main clutch;
the seventh branch is used for controlling the rising speed and the falling speed of the roller;
and the eighth branch is used for controlling the positive and negative blowing of the fan.
3. The adjustable speed harvester hydraulic system of claim 2 wherein: and a back pressure valve is arranged between the hydraulic actuating element of the second actuating loop and the electromagnetic valve, an oil outlet of the back pressure valve is connected with the oil return path, and the back pressure valve is used for keeping the hydraulic pressure of the hydraulic actuating element stable and preventing the cutting table from descending.
4. The adjustable speed harvester hydraulic system of claim 2 wherein: the electromagnetic valve is a three-position four-way electromagnetic valve.
5. The adjustable speed harvester hydraulic system of claim 2 wherein: the hydraulic actuating element of the actuating loop comprises a header oil cylinder, a grain discharging cylinder motor, a grain discharging cylinder oil cylinder, a reel oil cylinder, a main clutch motor, a roller motor and a fan motor.
6. The adjustable speed harvester hydraulic system of claim 2 wherein: and each valve block of the electromagnetic valve is arranged on the same valve group to form a multi-way valve.
7. The adjustable speed harvester hydraulic system of claim 5 wherein: the multi-way valve comprises a header valve block, a grain cylinder rotating valve block, a grain cylinder lifting valve block, a reel valve block, a main clutch valve block, a roller valve block and a fan valve block.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310687536.4A CN117345708A (en) | 2023-06-12 | 2023-06-12 | A speed-adjustable harvester hydraulic system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310687536.4A CN117345708A (en) | 2023-06-12 | 2023-06-12 | A speed-adjustable harvester hydraulic system |
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| Publication Number | Publication Date |
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| CN117345708A true CN117345708A (en) | 2024-01-05 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310687536.4A Pending CN117345708A (en) | 2023-06-12 | 2023-06-12 | A speed-adjustable harvester hydraulic system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118285229A (en) * | 2024-05-14 | 2024-07-05 | 广西科创农业科技集团有限责任公司 | Integrated sugarcane harvester hydraulic control system and method |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09121645A (en) * | 1995-10-31 | 1997-05-13 | Kubota Corp | Lawn mower |
| JP2000188917A (en) * | 1998-12-25 | 2000-07-11 | Iseki & Co Ltd | Work unit lifting device for work vehicles |
| CN203892280U (en) * | 2014-06-09 | 2014-10-22 | 常州信息职业技术学院 | Electro-hydraulic proportional valve control system of combined machine tool |
| CN106122134A (en) * | 2016-08-30 | 2016-11-16 | 浙江海宏液压科技股份有限公司 | A kind of hydraulic system of harvester |
| CN207848067U (en) * | 2017-12-25 | 2018-09-11 | 陕西汽车集团有限责任公司 | The automobile-used shoveling back pressure control hydraulic circuit of compression type refuse and compression garbage truck |
| CN209743270U (en) * | 2019-03-29 | 2019-12-06 | 江苏沃得农业机械有限公司 | Harvester hydraulic system |
| CN218207333U (en) * | 2022-09-13 | 2023-01-03 | 潍柴雷沃智慧农业科技股份有限公司 | A hydraulic drive system, header and harvester |
| CN220268058U (en) * | 2023-06-12 | 2023-12-29 | 武汉盛硕电子有限公司 | Harvester hydraulic system of adjustable speed |
-
2023
- 2023-06-12 CN CN202310687536.4A patent/CN117345708A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09121645A (en) * | 1995-10-31 | 1997-05-13 | Kubota Corp | Lawn mower |
| JP2000188917A (en) * | 1998-12-25 | 2000-07-11 | Iseki & Co Ltd | Work unit lifting device for work vehicles |
| CN203892280U (en) * | 2014-06-09 | 2014-10-22 | 常州信息职业技术学院 | Electro-hydraulic proportional valve control system of combined machine tool |
| CN106122134A (en) * | 2016-08-30 | 2016-11-16 | 浙江海宏液压科技股份有限公司 | A kind of hydraulic system of harvester |
| CN207848067U (en) * | 2017-12-25 | 2018-09-11 | 陕西汽车集团有限责任公司 | The automobile-used shoveling back pressure control hydraulic circuit of compression type refuse and compression garbage truck |
| CN209743270U (en) * | 2019-03-29 | 2019-12-06 | 江苏沃得农业机械有限公司 | Harvester hydraulic system |
| CN218207333U (en) * | 2022-09-13 | 2023-01-03 | 潍柴雷沃智慧农业科技股份有限公司 | A hydraulic drive system, header and harvester |
| CN220268058U (en) * | 2023-06-12 | 2023-12-29 | 武汉盛硕电子有限公司 | Harvester hydraulic system of adjustable speed |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118285229A (en) * | 2024-05-14 | 2024-07-05 | 广西科创农业科技集团有限责任公司 | Integrated sugarcane harvester hydraulic control system and method |
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