CN110953338B - Speed stabilizing control system - Google Patents
Speed stabilizing control system Download PDFInfo
- Publication number
- CN110953338B CN110953338B CN201911218605.7A CN201911218605A CN110953338B CN 110953338 B CN110953338 B CN 110953338B CN 201911218605 A CN201911218605 A CN 201911218605A CN 110953338 B CN110953338 B CN 110953338B
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- Prior art keywords
- gear pump
- oil
- electromagnetic valve
- valve
- port
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
- F16H61/38—Control of exclusively fluid gearing
- F16H61/40—Control of exclusively fluid gearing hydrostatic
- F16H61/4008—Control of circuit pressure
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
- F16H61/38—Control of exclusively fluid gearing
- F16H61/40—Control of exclusively fluid gearing hydrostatic
- F16H61/4183—Preventing or reducing vibrations or noise, e.g. avoiding cavitations
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
- F16H61/38—Control of exclusively fluid gearing
- F16H61/40—Control of exclusively fluid gearing hydrostatic
- F16H61/42—Control of exclusively fluid gearing hydrostatic involving adjustment of a pump or motor with adjustable output or capacity
- F16H61/425—Motor capacity control by electric actuators
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
- F16H61/38—Control of exclusively fluid gearing
- F16H61/40—Control of exclusively fluid gearing hydrostatic
- F16H61/44—Control of exclusively fluid gearing hydrostatic with more than one pump or motor in operation
Abstract
The invention provides a speed stabilizing control system, which comprises: one end of the gear pump is connected with the oil tank; one end of the overflow valve is connected with the oil tank, and the other end of the overflow valve is connected with the other end of the gear pump; a first working oil port of the first electromagnetic valve is connected with the other end of the gear pump, and an oil inlet of the second electromagnetic valve is connected with a second working oil port of the first electromagnetic valve; a control interface of the variable motor is connected with an oil inlet of the first electromagnetic valve, and the variable motor is used for controlling the running speed of the vehicle speed reducer; the closed pump is connected with the variable motor and is used for supplying oil to the variable motor; therefore, when the vehicle is in a downhill, the overflow valve is used for controlling the pressure of the gear pump, so that the pressure of the gear pump can be ensured to be always in a stable state, the displacement of the motor can be always in a stable state, and the vehicle is prevented from shaking due to overlarge speed change amplitude in the downhill process, so that the normal operation of the vehicle is ensured.
Description
Technical Field
The invention belongs to the technical field of vehicle control, and particularly relates to a speed stabilizing control system.
Background
When the bracket carrier of the closed hydraulic driving system is used, the speed change amplitude of the vehicle is large when the vehicle goes down a slope for a long time, so that the vehicle shakes, the effect of braking is accompanied, and the normal operation of the vehicle is seriously influenced.
In addition, a general speed stabilizing system can only stabilize the speed at a certain fixed value, so that the downhill speed is too high, and potential safety hazards exist when the vehicle runs downhill.
Disclosure of Invention
Aiming at the problems in the prior art, the embodiment of the invention provides a speed stabilizing control system which is used for solving the technical problem that a vehicle cannot normally run due to shaking of a vehicle body in the downhill process of a carrier in the prior art.
The embodiment of the invention provides a speed stabilizing control system, which comprises:
one end of the gear pump is connected with the oil tank;
one end of the overflow valve is connected with the oil tank, the other end of the overflow valve is connected with the other end of the gear pump, and the overflow valve is used for adjusting the working pressure of the gear pump;
a first working oil port of the first electromagnetic valve is connected with the other end of the gear pump;
an oil inlet of the second electromagnetic valve is connected with a second working oil port of the first electromagnetic valve;
the control interface of the variable motor is connected with the oil inlet of the first electromagnetic valve, and the variable motor is used for controlling the speed of a vehicle speed reducer;
and the closed pump is connected with the variable motor and is used for supplying oil to the variable motor.
Optionally, the system further comprises: and a first working oil port of the second electromagnetic valve is in a blocking state.
Optionally, the system further comprises: and a first end of the shuttle valve is connected with a first high-pressure oil port of the variable motor, a second end of the shuttle valve is connected with a second high-pressure oil port of the variable motor, and a third end of the shuttle valve is connected with a second working oil port of the second electromagnetic valve.
Optionally, the system further comprises: a filter; the filter is installed between the first electromagnetic valve and the gear pump and used for filtering impurities in the oil.
Optionally, an oil return port of the first solenoid valve is connected with the oil tank.
6. The system of claim 1, wherein the return port of the second solenoid valve is connected to the tank.
Optionally, an outlet of the closed pump is connected to an input end of the variable displacement motor, and an inlet of the closed pump is connected to an output end of the variable displacement motor.
The invention provides a speed stabilizing control system, which comprises: one end of the gear pump is connected with the oil tank; one end of the overflow valve is connected with the oil tank, the other end of the overflow valve is connected with the other end of the gear pump, and the overflow valve is used for adjusting the working pressure of the gear pump; a first working oil port of the first electromagnetic valve is connected with the other end of the gear pump; an oil inlet of the second electromagnetic valve is connected with a second working oil port of the first electromagnetic valve; the control interface of the variable motor is connected with the oil inlet of the first electromagnetic valve, and the variable motor is used for controlling the speed of a vehicle speed reducer; the closed pump is connected with the variable motor and is used for supplying oil to the variable motor; therefore, when the vehicle is in a downhill, the first electromagnetic valve is electrified, the pressure at the variable motor control interface is supplied by the gear pump, the pressure of the gear pump determines the displacement of the motor, the pressure of the gear pump is controlled by the overflow valve, so that the pressure of the gear pump can be ensured to be always in a stable state, the displacement of the motor can be always in a stable state, and the vehicle is prevented from shaking due to the fact that the speed variation amplitude is too large in the downhill process, and the normal operation of the vehicle is ensured.
Drawings
Fig. 1 is a schematic view of an overall structure of a speed stabilizing control system according to an embodiment of the present invention.
Detailed Description
In order to solve the technical problem that a vehicle cannot normally run due to shaking of the vehicle body in the downhill process of the carrier in the prior art, the embodiment of the invention provides a speed stabilizing control system, which comprises: one end of the gear pump is connected with the oil tank; one end of the overflow valve is connected with the oil tank, the other end of the overflow valve is connected with the other end of the gear pump, and the overflow valve is used for adjusting the working pressure of the gear pump; a first working oil port of the first electromagnetic valve is connected with the other end of the gear pump; an oil inlet of the second electromagnetic valve is connected with a second working oil port of the first electromagnetic valve; the control interface of the variable motor is connected with the oil inlet of the first electromagnetic valve, and the variable motor is used for controlling the speed of a vehicle speed reducer; and the closed pump is connected with the variable motor and is used for supplying oil to the variable motor.
The technical solution of the present invention is further described in detail by the accompanying drawings and the specific embodiments.
This embodiment provides a speed stabilizing control system, as shown in fig. 1, the system includes: the system comprises a gear pump 1, an overflow valve 2, a first electromagnetic valve 3, a second electromagnetic valve 4, a shuttle valve 5, a filter 6, a variable motor 7 and a closed pump 8; wherein the content of the first and second substances,
one end of the gear pump 1 is connected with an oil tank 9, and the gear pump 1 is used for providing pressure for the variable displacement motor 7. One end of the overflow valve 2 is connected with the oil tank 9, the other end of the overflow valve 2 is connected with the other end of the gear pump 1, and the overflow valve 2 is used for adjusting the working pressure of the gear pump 1. It is understood that the operating pressure of the gear pump 1 can be adjusted by presetting the pressure to the relief valve 2.
With continued reference to fig. 1, the first working oil port of the first electromagnetic valve 3 is connected to the other end of the gear pump 1; an oil inlet of the second electromagnetic valve 4 is connected with a second working oil port of the first electromagnetic valve 3. The oil return port of the first electromagnetic valve 3 is connected with the oil tank 9, the oil return port of the second electromagnetic valve 4 is connected with the oil tank 9, the oil return port of the first electromagnetic valve 3 is connected with the oil return port of the second electromagnetic valve 4, and the first working oil port of the second electromagnetic valve 4 is in a plugging state.
Here, the first solenoid valve 3 and the second solenoid valve 4 have the same structure, and each include: the first working oil port B, the second working oil port A, the oil inlet P and the oil return port T.
In order to filter impurities in the oil, the first electromagnetic valve 3 and a filter 6 is further installed between the gear pump 1, that is, the other end of the gear pump 1 is connected with one end of the filter 6, and the other end of the filter 6 is connected with a first working oil port of the first electromagnetic valve 3. Thus, the oil pumped out from the oil tank 9 by the gear pump 1 enters the first working oil port of the first electromagnetic valve after being filtered by the filter 3.
A control interface G port of the variable motor 7 is connected with an oil inlet of the first electromagnetic valve 3, and an output end of the variable motor 7 is connected with a vehicle speed reducer and used for controlling the running speed of the vehicle speed reducer; the closed pump 8 is connected with the variable motor 7 and is used for supplying oil to the variable motor 7. Specifically, an outlet of the closed pump 8 is connected with an input end of the variable displacement motor 7, and an inlet of the closed pump 8 is connected with an output end of the variable displacement motor 7.
Here, in order to avoid power consumption during normal level road running, a first end of the shuttle valve 5 is connected to a first high-pressure port of the variable motor 7, a second end of the shuttle valve 5 is connected to a second high-pressure port of the variable motor 7, and a third end of the shuttle valve 5 is connected to a second working port of the second solenoid valve 4. Therein, referring to fig. 1, the variable displacement motor 7 has two high-pressure oil ports: a first high-pressure port a1 and a second high-pressure port B1.
In the actual running process, under the normal flat road running state, the electromagnet of the first electromagnetic valve 3 and the electromagnet of the second electromagnetic valve 4 are not powered, the shuttle valve 5 selects the pressure oil with higher pressure in the first high-pressure oil port a1 and the second high-pressure oil port B1 in the variable motor 7, and then the pressure oil passes through the second working oil port of the second electromagnetic valve 4 to the oil inlet of the second electromagnetic valve 4, reaches the second working oil port of the first electromagnetic valve 3 and the oil inlet of the first electromagnetic valve 3, and then reaches the control port of the variable motor 7, so as to control the displacement of the variable motor 7. At this time, the oil liquid of the gear pump 1 returns to the oil tank for unloading from the oil return port of the first electromagnetic valve 3 through the filter 6, the gear pump 1 is in a low-pressure state, and the power consumption of the system is minimum, so that the power consumption of the system can be reduced in a non-downhill working condition.
When the working condition is downhill, the electromagnet of the first electromagnetic valve 3 and the electromagnet of the second electromagnetic valve 4 are simultaneously powered on, the electromagnet of the first electromagnetic valve 3 and the electromagnet of the second electromagnetic valve 4 are simultaneously reversed, pressure oil behind the shuttle valve 5 cannot reach a control port of the motor through the second electromagnetic valve 4, the pressure of the control port of the variable motor comes from the gear pump 1, and oil of the gear pump 1 passes through the filter 5, the first working oil port of the first electromagnetic valve 3 and the oil inlet of the first electromagnetic valve 3 to reach the control port of the variable motor 7. The gear pump 1 is in a high-pressure working state, the working pressure of the gear pump 1 depends on the set pressure of the overflow valve 2, and the pressure of the gear pump 1 determines the displacement of the motor 7.
Therefore, the pressure value from the gear pump 1 to the variable cavity of the variable motor can be adjusted by setting the pressure of the overflow valve 2, so that the variable motor 7 has enough pressure value and can be always kept in a stable state when the vehicle is in a downhill working condition, the vehicle speed is always kept in the stable state when the vehicle is in the downhill working condition, and the vehicle body is prevented from shaking.
In addition, the pressure of the gear pump 1 can be adjusted in real time according to the actual gradient of a downhill, so that the pressure of a variable cavity of the motor can be adjusted in real time, the speed of the vehicle in the downhill process can be adjusted, and the potential safety hazard caused by the fact that the speed of the vehicle cannot be controlled in the downhill process can be avoided.
The speed stabilizing control system provided by the embodiment of the invention has the following beneficial effects that:
the invention provides a speed stabilizing control system, which comprises: one end of the gear pump is connected with the oil tank; one end of the overflow valve is connected with the oil tank, the other end of the overflow valve is connected with the other end of the gear pump, and the overflow valve is used for adjusting the working pressure of the gear pump; a first working oil port of the first electromagnetic valve is connected with the other end of the gear pump; an oil inlet of the second electromagnetic valve is connected with a second working oil port of the first electromagnetic valve; the control interface of the variable motor is connected with the oil inlet of the first electromagnetic valve, and the variable motor is used for controlling the speed of a vehicle speed reducer; the closed pump is connected with the variable motor and is used for supplying oil to the variable motor; therefore, when the vehicle is in a downhill, the first electromagnetic valve is electrified, the pressure at the variable motor control interface is supplied by the gear pump, the pressure of the gear pump determines the displacement of the motor, and the pressure of the gear pump is controlled by the overflow valve to ensure that the pressure of the gear pump is always in a stable state, so that the displacement of the motor is always in the stable state, and the vehicle is prevented from shaking due to overlarge speed variation amplitude in the downhill process, and the normal operation of the vehicle is ensured; in addition, during normal level road running, when the vehicle is in a level road running state, the second electromagnetic valve and the second electromagnetic valve are not electrified, at the moment, the gear pump is directly connected with the oil return tank for unloading through the first electromagnetic valve, and the system power cannot be increased; in addition, in the downhill process, the pressure of the gear pump can be adjusted in real time according to the actual gradient, so that the vehicle speed in the downhill process can be adjusted in real time, and the problem that potential safety hazards exist due to the fact that the vehicle speed cannot be controlled in the downhill process is solved.
The above description is only exemplary of the present invention and should not be taken as limiting the scope of the present invention, and any modifications, equivalents, improvements, etc. that are within the spirit and principle of the present invention should be included in the present invention.
Claims (7)
1. A speed stabilization control system, the system comprising:
one end of the gear pump is connected with the oil tank;
one end of the overflow valve is connected with the oil tank, the other end of the overflow valve is connected with the other end of the gear pump, and the overflow valve is used for adjusting the working pressure of the gear pump;
a first working oil port of the first electromagnetic valve is connected with the other end of the gear pump;
an oil inlet of the second electromagnetic valve is connected with a second working oil port of the first electromagnetic valve;
the control interface of the variable motor is connected with the oil inlet of the first electromagnetic valve, and the variable motor is used for controlling the speed of a vehicle speed reducer;
the closed pump is connected with the variable motor and is used for supplying oil to the variable motor;
wherein the displacement of the variable displacement motor is related to the working pressure of the gear pump.
2. The system of claim 1, wherein the first working port of the second solenoid valve is in a blocked state.
3. The system of claim 1, wherein the system further comprises: and a first end of the shuttle valve is connected with a first high-pressure oil port of the variable motor, a second end of the shuttle valve is connected with a second high-pressure oil port of the variable motor, and a third end of the shuttle valve is connected with a second working oil port of the second electromagnetic valve.
4. The system of claim 1, wherein the system further comprises: a filter; the filter is installed between the first electromagnetic valve and the gear pump and used for filtering impurities in the oil.
5. The system of claim 1, wherein the return port of the first solenoid valve is connected to the tank.
6. The system of claim 1, wherein the return port of the second solenoid valve is connected to the tank.
7. The system of claim 1, wherein an outlet of the closed-loop pump is connected to an input of the variable displacement motor and an inlet of the closed-loop pump is connected to an output of the variable displacement motor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911218605.7A CN110953338B (en) | 2019-12-03 | 2019-12-03 | Speed stabilizing control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911218605.7A CN110953338B (en) | 2019-12-03 | 2019-12-03 | Speed stabilizing control system |
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| Publication Number | Publication Date |
|---|---|
| CN110953338A CN110953338A (en) | 2020-04-03 |
| CN110953338B true CN110953338B (en) | 2021-04-20 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201911218605.7A Active CN110953338B (en) | 2019-12-03 | 2019-12-03 | Speed stabilizing control system |
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Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN87102639A (en) * | 1986-06-11 | 1987-12-23 | 株式会社岛津制作所 | Hydraulic system |
| US5323611A (en) * | 1989-08-30 | 1994-06-28 | Kabushiki Kaisha Komatsu Seisakusho | Speed change controller of running hydraulic motor |
| JPH11182674A (en) * | 1997-12-17 | 1999-07-06 | Komatsu Ltd | Device and method for controlling forward/backward switching of hydraulic driven vehicle |
| JP2000193086A (en) * | 1998-12-28 | 2000-07-14 | Hitachi Constr Mach Co Ltd | Continuously variable shift hydraulic running drive device |
| JP2005207499A (en) * | 2004-01-22 | 2005-08-04 | Hitachi Constr Mach Co Ltd | Hydraulic circuit of construction machine |
| JP2005207498A (en) * | 2004-01-22 | 2005-08-04 | Hitachi Constr Mach Co Ltd | Hydraulic circuit of construction machine |
| CN1695017A (en) * | 2003-01-29 | 2005-11-09 | 布鲁宁赫斯海诺马帝克有限公司 | Control of a hydrostatic gearbox |
| CN101535687A (en) * | 2006-12-28 | 2009-09-16 | 日立建机株式会社 | Travel control device for hydraulic traveling vehicle |
| CN101563555A (en) * | 2006-12-20 | 2009-10-21 | 丰田自动车株式会社 | Controller of transmission of variable-capacity pump motor type |
| CN102575764A (en) * | 2009-10-09 | 2012-07-11 | Zf腓德烈斯哈芬股份公司 | Device for varying the swept volumes of a first hydraulic machine and a second hydraulic machine |
| CN104937178A (en) * | 2013-01-25 | 2015-09-23 | 沃尔沃建造设备有限公司 | Driving control device of construction machine |
| CN106168288A (en) * | 2015-05-21 | 2016-11-30 | 丹佛斯动力系统有限责任两合公司 | The regulation that the load of hydraulic motor is relevant |
-
2019
- 2019-12-03 CN CN201911218605.7A patent/CN110953338B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN87102639A (en) * | 1986-06-11 | 1987-12-23 | 株式会社岛津制作所 | Hydraulic system |
| US5323611A (en) * | 1989-08-30 | 1994-06-28 | Kabushiki Kaisha Komatsu Seisakusho | Speed change controller of running hydraulic motor |
| JPH11182674A (en) * | 1997-12-17 | 1999-07-06 | Komatsu Ltd | Device and method for controlling forward/backward switching of hydraulic driven vehicle |
| JP2000193086A (en) * | 1998-12-28 | 2000-07-14 | Hitachi Constr Mach Co Ltd | Continuously variable shift hydraulic running drive device |
| CN1695017A (en) * | 2003-01-29 | 2005-11-09 | 布鲁宁赫斯海诺马帝克有限公司 | Control of a hydrostatic gearbox |
| JP2005207499A (en) * | 2004-01-22 | 2005-08-04 | Hitachi Constr Mach Co Ltd | Hydraulic circuit of construction machine |
| JP2005207498A (en) * | 2004-01-22 | 2005-08-04 | Hitachi Constr Mach Co Ltd | Hydraulic circuit of construction machine |
| CN101563555A (en) * | 2006-12-20 | 2009-10-21 | 丰田自动车株式会社 | Controller of transmission of variable-capacity pump motor type |
| CN101535687A (en) * | 2006-12-28 | 2009-09-16 | 日立建机株式会社 | Travel control device for hydraulic traveling vehicle |
| CN102575764A (en) * | 2009-10-09 | 2012-07-11 | Zf腓德烈斯哈芬股份公司 | Device for varying the swept volumes of a first hydraulic machine and a second hydraulic machine |
| CN104937178A (en) * | 2013-01-25 | 2015-09-23 | 沃尔沃建造设备有限公司 | Driving control device of construction machine |
| CN106168288A (en) * | 2015-05-21 | 2016-11-30 | 丹佛斯动力系统有限责任两合公司 | The regulation that the load of hydraulic motor is relevant |
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| CN110953338A (en) | 2020-04-03 |
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