CN112343876B - Pressure balance self-protection hydraulic system with double hydraulic motors - Google Patents
Pressure balance self-protection hydraulic system with double hydraulic motors Download PDFInfo
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- CN112343876B CN112343876B CN202011272538.XA CN202011272538A CN112343876B CN 112343876 B CN112343876 B CN 112343876B CN 202011272538 A CN202011272538 A CN 202011272538A CN 112343876 B CN112343876 B CN 112343876B
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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
- F15B11/08—Servomotor systems without provision for follow-up action; Circuits therefor with only one servomotor
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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
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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
- F15B13/027—Check valves
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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
- F15B20/00—Safety arrangements for fluid actuator systems; Applications of safety devices in fluid actuator systems; Emergency measures for fluid actuator systems
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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
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention provides a double-hydraulic-motor pressure balance self-protection hydraulic system which comprises a first bidirectional motor, a first balance valve, a second bidirectional motor, a first explosion-proof valve, a second explosion-proof valve, a control oil port WA, a control oil port WB and an oil return port WT, wherein the first balance valve is arranged on the first bidirectional motor; through setting up first explosion-proof valve and second explosion-proof valve, can improve two-way hydraulic motor's stability and security.
Description
Technical Field
The invention relates to a pressure balance self-protection hydraulic system with double hydraulic motors.
Background
The double oil cylinders of the actuating mechanism in the prior art solve the problem of different pressures of the two oil cylinders by installing a balance valve.
The application document with the Chinese application number of 201110365008.4, the publication date of 2012.6.20 discloses a bridge detection operation vehicle double-oil-cylinder synchronization system, and the system at least contains double-drive oil cylinders, a balance valve and two one-way back pressure valves for independently adjusting back pressure, the double-drive oil cylinders are double-acting cylinders, two ends of each drive oil cylinder are respectively hinged with a fixing seat and a U-shaped cross-section working platform, the two drive oil cylinders and the oil circuit connection of the two drive oil cylinders are in parallel connection, the one-way back pressure valves are respectively connected between working oil ports of rod cavity oil ports of the two drive oil cylinders and the balance valve, or are not connected between the rod cavity oil ports of the two drive oil cylinders and the direction valve through the balance valve, and the rodless cavity oil circuits of the two drive oil cylinders are respectively connected with another working oil port of the balance valve after being converged. The substitute of the one-way back pressure valve is a one-way back pressure valve group for independently adjusting back pressure.
But oil ports of rod cavities of two driving oil cylinders of the system are only connected with one-way back pressure valve; meanwhile, the two one-way back pressure valves are respectively connected with the balance valve, and the two one-way back pressure valves are not connected; when hydraulic oil flows in from the port A of the balance valve, the hydraulic oil flows through one of the driving oil cylinders and the one-way back pressure valve connected with the driving oil cylinder, and then flows out from the port B of the balance valve; hydraulic oil cannot circulate between the two driving oil cylinders; the pressure balance of the two driving oil cylinders can not be realized, so that when two one-way back pressure valve sections are inconsistent or the performances are different, the pressure between the two driving oil cylinders is different, and the driving oil cylinders can shake during working. Meanwhile, when the pipeline in the system leaks or explodes, the communication oil port cannot be automatically closed, so that the safety and the reliability of the system are low.
Disclosure of Invention
The invention provides a pressure balance self-protection hydraulic system with double hydraulic motors.
In order to achieve the purpose, the technical scheme of the invention is as follows: a pressure balance self-protection hydraulic system of a double-hydraulic motor comprises a first bidirectional motor, a first balance valve, a second bidirectional motor, a first explosion-proof valve, a second explosion-proof valve, a control oil port WA, a control oil port WB and an oil return port WT;
the first and second bidirectional motors and the oil passages thereof are connected in parallel, one ends of the first and second bidirectional motors are connected with the control oil port WA, and the other ends of the first and second bidirectional motors are connected with the oil return port WT; the oil drainage ports of the first bidirectional motor and the second bidirectional motor are connected with an oil return port WT; the control oil port WA, the control oil port WB and the oil return port WT are connected with an oil tank;
the first balance valve is connected between the other end of the first bidirectional motor and the control oil port WB; the second balance valve is connected between the other end of the second bidirectional motor and the control oil port WB; the other end of the first bidirectional motor is also connected with a first explosion-proof valve; the other end of the second bidirectional motor is also connected with a second explosion-proof valve; the first explosion-proof valve is also connected with the second explosion-proof valve; and the control oil ports of the first balance valve and the second balance valve are also connected with a control oil port WA.
Further, the first balance valve comprises a first check valve and a first overflow valve; an oil inlet of the first overflow valve is connected with the other end of the first bidirectional motor, and an oil outlet of the first overflow valve is connected with a control oil port WB; a control oil port of the first overflow valve is connected with a control oil port WA; an oil inlet of the first check valve is connected with an oil outlet of the first overflow valve, and an oil outlet of the first check valve is connected with an oil inlet of the first overflow valve.
Further, the second balance valve comprises a second check valve and a second overflow valve; an oil inlet of the second overflow valve is connected with the other end of the second bidirectional motor, and an oil outlet of the second overflow valve is connected with a control oil port WB; a control oil port of the second overflow valve is connected with a control oil port WA; an oil inlet of the second one-way valve is connected with an oil outlet of the second overflow valve, and an oil outlet of the second one-way valve is connected with an oil inlet of the second overflow valve.
Furthermore, a port B of the first explosion-proof valve is connected with the other end of the first bidirectional motor, a port F of the first explosion-proof valve is connected with a port F of the second explosion-proof valve, a port B of the second explosion-proof valve is connected with the other end of the second bidirectional motor, a first throttle valve in the first explosion-proof valve is arranged close to the port F of the first explosion-proof valve, and a second throttle valve in the second explosion-proof valve is arranged close to the port F of the second explosion-proof valve.
Furthermore, the control oil ports WA and WB are connected with an oil tank through a hydraulic pump through a reversing valve.
The working principle of the hydraulic system is as follows: the hydraulic oil is pumped into the control oil port WA through the reversing valve by the hydraulic pump, the hydraulic oil respectively enters the first bidirectional motor and the second bidirectional motor from the control oil port WA, meanwhile, the hydraulic oil of the control oil port WA is respectively input into the control oil port of the first balance valve and the control oil port of the second balance valve, in the process of feeding the hydraulic oil, the hydraulic oil flows back to the control oil port WB from the first bidirectional motor through the first balance valve and then flows back to the oil tank, and meanwhile, the hydraulic oil flows back to the control oil port WB from the second bidirectional motor through the second balance valve and then flows back to the oil tank. In the process, when the oil pressure between the first bidirectional motor and the second bidirectional motor is unbalanced, because the first explosion-proof valve and the second explosion-proof valve are communicated in two directions during normal operation, the first bidirectional motor and the second bidirectional motor are communicated through the first explosion-proof valve and the second explosion-proof valve, the oil pressure of the first bidirectional motor and the oil pressure of the second bidirectional motor are automatically balanced, if the oil quantity of the output end of one bidirectional motor is obviously reduced due to failure and the like, the oil pressure of the output end of the other bidirectional motor is larger than that of the other bidirectional motor, and thus the explosion-proof valve close to the end with the large oil pressure is cut off to avoid the phenomenon of oil leakage of the two bidirectional motors, so that the other bidirectional motor can normally operate, and the one bidirectional motor can be better protected.
If the hydraulic oil flows in from the control oil port WB through the control reversing valve, the hydraulic oil enters the first bidirectional motor through the first balance valve, and return oil of the first bidirectional motor flows back from the control oil port WA; meanwhile, the hydraulic oil enters the second bidirectional motor through the second balance valve, and the return oil of the second bidirectional motor flows back from the control oil port WA.
Therefore, the system can not only balance the pressure and the oil pressure of the two bidirectional motors and effectively reduce the vibration, but also ensure the normal work of one bidirectional motor when the oil pressure is overlarge and protect the other bidirectional motor so as to improve the safety and the stability of the hydraulic system.
Drawings
Fig. 1 is a hydraulic schematic of the present invention.
Detailed Description
The invention is described in further detail below with reference to the drawings and the detailed description.
As shown in FIG. 1; a double-hydraulic-motor pressure-balance self-protection hydraulic system comprises an oil tank, a first bidirectional motor 5, a first balance valve 1, a second balance valve 2, a second bidirectional motor 6, a first explosion-proof valve 3, a second explosion-proof valve 4, a control oil port WA, a control oil port WB and an oil return port WT; the control oil port LA and the control oil port WA are connected with one oil port of the oil tank, the control oil port WB and the control oil port LB are connected with the other oil port of the oil tank, and the oil return port WT is connected with an oil return port of the oil tank.
The first and second bidirectional motors 5 and 6 and the oil passages thereof are connected in parallel, one ends of the first and second bidirectional motors 5 and 6 are connected with the control oil port WA, and the other ends of the first and second bidirectional motors 5 and 6 are connected with the oil return port WT; the oil discharge ports of the first and second bidirectional motors 5 and 6 are connected with an oil return port WT; the control oil port WA, the control oil port WB and the oil return port WT are connected with an oil tank.
The first balance valve 1 is connected between the other end of the first bidirectional motor 5 and the control oil port WB; the second balance valve 2 is connected between the other end of the second bidirectional motor 6 and the control oil port WB; the other end of the first bidirectional motor 5 is also connected with the first explosion-proof valve 3; the other end of the second bidirectional motor 6 is also connected with a second explosion-proof valve 4; the first explosion-proof valve 3 is also connected with a second explosion-proof valve 4; the control oil ports of the first balance valve 1 and the second balance valve 2 are also connected with a control oil port WA.
The first balance valve 1 comprises a first check valve 12 and a first overflow valve 11; the second balance valve 2 includes a second check valve 22 and a second relief valve 21.
An oil inlet of the first overflow valve 11 is connected with the other end of the first bidirectional motor 5, and an oil outlet of the first overflow valve 11 is connected with a control oil port WB; the control port of the first overflow valve 11 is connected to the control port WA.
An oil inlet of the second overflow valve 21 is connected with the other end of the second bidirectional motor 6, and an oil outlet of the second overflow valve 21 is connected with a control oil port WB; the control port of the first overflow valve 11 is connected to the control port WA.
The port B of the first explosion-proof valve 3 is connected with the other end of the first bidirectional motor 5, the port F of the first explosion-proof valve 3 is connected with the port F of the second explosion-proof valve 4, the port B of the second explosion-proof valve 4 is connected with the other end of the second bidirectional motor 6, the first throttling valve 33 in the first explosion-proof valve 3 is arranged close to the port F of the first explosion-proof valve 3, and the second throttling valve 43 in the second explosion-proof valve 4 is arranged close to the port F of the second explosion-proof valve 4.
The working principle of the self-balancing protection hydraulic system is as follows: hydraulic oil is pumped into the control oil port WA through the hydraulic pump and is led to enter the first two-way motor 5 and the second two-way motor 6 through the reversing valve, the hydraulic oil respectively enters the first two-way motor 5 and the second two-way motor 6 from the control oil port WA, meanwhile, the hydraulic oil of the control oil port WA is respectively input into the control oil ports of the first balance valve 1 and the second balance valve 2, in the process of feeding the hydraulic oil, the hydraulic oil flows back to the control oil port WB from the first two-way motor 5 through the first balance valve 1 and then flows back to the oil tank, and meanwhile, the hydraulic oil flows back to the control oil port WB from the second two-way motor 6 through the second balance valve 2 and then flows back to the oil tank. In the above process, when the oil pressure between the first bidirectional motor 5 and the second bidirectional motor 6 is unbalanced, because the first explosion-proof valve 3 and the second explosion-proof valve 4 are communicated in two directions during normal operation, in this way, the first and second bidirectional motors are communicated through the first explosion-proof valve 3 and the second explosion-proof valve 4, so that the oil pressure of the first and second bidirectional motors is automatically balanced, if the oil volume at the output end of one of the bidirectional motors is obviously reduced due to a fault or the like, the oil pressure at the output end of the other bidirectional motor is greater than that of one of the bidirectional motors, in this way, the explosion-proof valve near the end with the large oil pressure is cut off, and the phenomenon of oil cross between the two bidirectional motors is avoided, so that the other bidirectional motor can operate normally, and can better protect one of the bidirectional motors.
If the hydraulic oil flows in from the control oil port WB through the control reversing valve, the hydraulic oil enters the first bidirectional motor 5 through the first balance valve 1, and the return oil of the first bidirectional motor 5 flows back from the control oil port WA; meanwhile, the hydraulic oil enters the second bidirectional motor 6 through the second balance valve 2, and the return oil of the second bidirectional motor 6 flows back from the control port WA.
Therefore, the system can not only balance the pressure and the oil pressure of the two bidirectional motors and effectively reduce the vibration, but also ensure the normal work of one bidirectional motor when the oil pressure is overlarge and protect the other bidirectional motor so as to improve the safety and the stability of the hydraulic system.
Claims (5)
1. The utility model provides a two hydraulic motor pressure balance self preservation protect hydraulic system which characterized in that: the system comprises a first bidirectional motor, a first balance valve, a second bidirectional motor, a first explosion-proof valve, a second explosion-proof valve, a control oil port WA, a control oil port WB and an oil return port WT;
the first and second bidirectional motors and the oil passages thereof are connected in parallel, one ends of the first and second bidirectional motors are connected with the control oil port WA, and the other ends of the first and second bidirectional motors are connected with the oil return port WT; oil drain ports of the first bidirectional motor and the second bidirectional motor are connected with an oil return port WT; the control oil port WA, the control oil port WB and the oil return port WT are connected with an oil tank;
the first balance valve is connected between the other end of the first bidirectional motor and the control oil port WB; the second balance valve is connected between the other end of the second bidirectional motor and the control oil port WB; the other end of the first bidirectional motor is also connected with a first explosion-proof valve; the other end of the second bidirectional motor is also connected with a second explosion-proof valve; the first explosion-proof valve is also connected with the second explosion-proof valve; the control oil ports of the first balance valve and the second balance valve are also connected with a control oil port WA; when the oil pressure of the output end of the other two-way motor is larger than that of the output end of one of the two-way motors, the explosion-proof valve close to the end with the large oil pressure is cut off.
2. The dual hydraulic motor pressure balanced self protecting hydraulic system as claimed in claim 1, wherein: the first balance valve comprises a first check valve and a first overflow valve; an oil inlet of the first overflow valve is connected with the other end of the first bidirectional motor, and an oil outlet of the first overflow valve is connected with a control oil port WB; a control oil port of the first overflow valve is connected with a control oil port WA; an oil inlet of the first check valve is connected with an oil outlet of the first overflow valve, and an oil outlet of the first check valve is connected with an oil inlet of the first overflow valve.
3. The dual hydraulic motor pressure balanced self protecting hydraulic system as claimed in claim 1, wherein: the second balance valve comprises a second check valve and a second overflow valve; an oil inlet of the second overflow valve is connected with the other end of the second bidirectional motor, and an oil outlet of the second overflow valve is connected with a control oil port WB; a control oil port of the second overflow valve is connected with a control oil port WA; an oil inlet of the second check valve is connected with an oil outlet of the second overflow valve, and an oil outlet of the second check valve is connected with an oil inlet of the second overflow valve.
4. The dual hydraulic motor pressure balanced self protecting hydraulic system as claimed in claim 1, wherein: the other end of first bi-directional motor is connected to the B mouth of first explosion-proof valve, and the F mouth of second explosion-proof valve is connected to the F mouth of first explosion-proof valve, and the other end of second bi-directional motor is connected to the B mouth of second explosion-proof valve, and the setting of F mouth that first choke valve is close to first explosion-proof valve is close to first throttle valve in the first explosion-proof valve, and the setting of F mouth that the second choke valve is close to the second explosion-proof valve is close to the second throttle valve in the second explosion-proof valve.
5. The dual hydraulic motor pressure balanced self protecting hydraulic system as claimed in claim 1, wherein: the control oil ports WA and WB are connected with an oil tank through a hydraulic pump by a reversing valve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011272538.XA CN112343876B (en) | 2020-11-13 | 2020-11-13 | Pressure balance self-protection hydraulic system with double hydraulic motors |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011272538.XA CN112343876B (en) | 2020-11-13 | 2020-11-13 | Pressure balance self-protection hydraulic system with double hydraulic motors |
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| Publication Number | Publication Date |
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| CN112343876A CN112343876A (en) | 2021-02-09 |
| CN112343876B true CN112343876B (en) | 2023-03-14 |
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| CN202011272538.XA Active CN112343876B (en) | 2020-11-13 | 2020-11-13 | Pressure balance self-protection hydraulic system with double hydraulic motors |
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02155879A (en) * | 1988-05-12 | 1990-06-14 | Hitachi Constr Mach Co Ltd | Hydraulic driving device for crawler type construction vehicle |
| CN102562697A (en) * | 2012-02-28 | 2012-07-11 | 徐州重型机械有限公司 | Crane and synchronous hydraulic system with double cylinders |
| CN102588365A (en) * | 2012-03-13 | 2012-07-18 | 徐州重型机械有限公司 | Double-cylinder synchronous control hydraulic system and engineering machinery |
| CN102628459A (en) * | 2012-04-12 | 2012-08-08 | 中联重科股份有限公司 | Multi-oil-cylinder synchronous control system and engineering vehicle |
| CN102659049A (en) * | 2012-05-07 | 2012-09-12 | 三一汽车起重机械有限公司 | Dual-winch hydraulic control system and engineering machine |
| CN202468502U (en) * | 2012-03-13 | 2012-10-03 | 徐州重型机械有限公司 | Dual-cylinder synchronous control hydraulic system and engineering machinery |
| CN102979772A (en) * | 2012-12-10 | 2013-03-20 | 徐州重型机械有限公司 | Oil cylinder locking device, double-cylinder hydraulic control system and lifting equipment |
| DE102013012332A1 (en) * | 2013-07-25 | 2015-01-29 | Hydac Fluidtechnik Gmbh | control system |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109809311A (en) * | 2019-01-31 | 2019-05-28 | 武汉船用机械有限责任公司 | The Hydraulic slewing system and crane of crane |
-
2020
- 2020-11-13 CN CN202011272538.XA patent/CN112343876B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02155879A (en) * | 1988-05-12 | 1990-06-14 | Hitachi Constr Mach Co Ltd | Hydraulic driving device for crawler type construction vehicle |
| CN102562697A (en) * | 2012-02-28 | 2012-07-11 | 徐州重型机械有限公司 | Crane and synchronous hydraulic system with double cylinders |
| CN102588365A (en) * | 2012-03-13 | 2012-07-18 | 徐州重型机械有限公司 | Double-cylinder synchronous control hydraulic system and engineering machinery |
| CN202468502U (en) * | 2012-03-13 | 2012-10-03 | 徐州重型机械有限公司 | Dual-cylinder synchronous control hydraulic system and engineering machinery |
| CN102628459A (en) * | 2012-04-12 | 2012-08-08 | 中联重科股份有限公司 | Multi-oil-cylinder synchronous control system and engineering vehicle |
| CN102659049A (en) * | 2012-05-07 | 2012-09-12 | 三一汽车起重机械有限公司 | Dual-winch hydraulic control system and engineering machine |
| CN102979772A (en) * | 2012-12-10 | 2013-03-20 | 徐州重型机械有限公司 | Oil cylinder locking device, double-cylinder hydraulic control system and lifting equipment |
| DE102013012332A1 (en) * | 2013-07-25 | 2015-01-29 | Hydac Fluidtechnik Gmbh | control system |
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| CN112343876A (en) | 2021-02-09 |
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