CN108533556B - Oil supplementing switching valve for switching closed system and open system and control system - Google Patents
Oil supplementing switching valve for switching closed system and open system and control system Download PDFInfo
- Publication number
- CN108533556B CN108533556B CN201810660602.8A CN201810660602A CN108533556B CN 108533556 B CN108533556 B CN 108533556B CN 201810660602 A CN201810660602 A CN 201810660602A CN 108533556 B CN108533556 B CN 108533556B
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- closed
- cartridge
- cartridge valve
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- 230000001502 supplementing effect Effects 0.000 title claims abstract description 56
- 239000003921 oil Substances 0.000 claims description 160
- 238000000034 method Methods 0.000 claims description 7
- 238000007789 sealing Methods 0.000 claims description 6
- 239000010729 system oil Substances 0.000 claims description 2
- 230000006872 improvement Effects 0.000 description 7
- 230000004044 response Effects 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 238000005265 energy consumption Methods 0.000 description 2
- 238000004891 communication Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 239000010720 hydraulic oil Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
Classifications
-
- 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
- F15B13/022—Flow-dividers; Priority valves
Abstract
An oil supplementing switching valve and a control system for switching a closed system and an open system. The closed pump solves the problems that the existing closed pump can only be used for a closed system and the open system can not switch control output. The device comprises a first reversing valve, a second reversing valve, an overflow valve, a first cartridge valve, a second cartridge valve, a third cartridge valve, an oil supplementing port, a closed pump interface and a working interface; the first cartridge valve is characterized in that an oil inlet of the first cartridge valve is connected with an oil supplementing port, an oil outlet of the first cartridge valve is connected with an oil tank, and a throttling port is arranged between the oil inlet of the first cartridge valve and a control cavity of the first cartridge valve; the second cartridge valve and the third cartridge valve are respectively provided with two positions, and the positions of the second cartridge valve and the third cartridge valve are changed through reversing control of the first reversing valve and the second reversing valve, so that switching control of a closed system and an open system is realized. The invention also has the advantages of convenient control, reliable switching, low cost, stable performance, long service life and the like.
Description
Technical Field
The invention relates to a closed hydraulic control system and an open hydraulic control system, in particular to an oil supplementing switching valve for switching between the closed hydraulic control system and the open hydraulic control system and a control system.
Background
The hydraulic system of the engineering machinery comprises an open system and a closed system, wherein the open system is that an inlet of a hydraulic pump and an outlet of an actuator are communicated with an oil tank. A closed system means that the outlet of the actuator is directly connected to the inlet of the hydraulic pump, instead of the return tank. The hydraulic oil output by the pump returns to the inlet of the pump after passing through the actuator, is sucked by the pump and is discharged again, so that a closed cycle is formed. Closed systems have many advantages over open systems, but there are also limitations to closed systems, such as unequal areas of action on both sides of the actuator, and unequal flow rates required for actuation of the actuator in both directions, which is not suitable for closed circuits. However, the construction machine includes not only actuators (hydraulic motors) having equal side areas but also a plurality of actuators (differential cylinders) having unequal side areas.
For a large-tonnage automobile crane, a revolving and hoisting system is a multipurpose closed system, but an actuator for amplitude variation and telescopic action is a differential cylinder, and the closed system is not suitable for being adopted. If the closed variable pump can be used in the closed system and can be switched into the open system to serve as an oil source of the open system, the utilization rate of the variable pump can be improved, an open variable pump can be saved, the cost is greatly saved, and the market competitiveness of a host is improved.
Disclosure of Invention
The invention provides an oil supplementing switching valve and a control system for switching a closed system and an open system, which are used for solving the problems that the existing closed pump can only be used for the closed system and the open system can not switch control output in the background art.
The technical scheme of the invention is as follows: the oil supplementing switching valve comprises a first reversing valve, a second reversing valve, an overflow valve, a first cartridge valve, a second cartridge valve, a third cartridge valve, an oil supplementing port, a closed pump interface and a working interface;
the first reversing valve is used for connecting the first cartridge valve control cavity with the first position of the oil tank and connecting the first cartridge valve control cavity with the oil inlet of the overflow valve;
the second reversing valve is used for sealing the pressure oil of the second cartridge valve control cavity, connecting the third cartridge valve control cavity with the oil tank, and connecting the second cartridge valve control cavity with the oil tank, and sealing the pressure oil of the third cartridge valve control cavity;
the first cartridge valve is characterized in that an oil inlet of the first cartridge valve is connected with an oil supplementing port, an oil outlet of the first cartridge valve is connected with an oil tank, and a throttling port is arranged between the oil inlet of the first cartridge valve and a control cavity of the first cartridge valve;
the second cartridge valve is opened when the first reversing valve is in the second position and the second reversing valve is in the second position, so that the pressure oil of the oil supplementing port is connected with the closed pump interface through the second cartridge valve to form a first position controlled by the open system, and the second position is closed when the first reversing valve is in the first position and/or the second reversing valve is in the first position;
and the third cartridge valve is opened when the second reversing valve is in the first position, so that the pressure oil of the closed pump interface is connected with the working interface through the third cartridge valve to realize the first position of closed system control, and the second valve is closed when the second reversing valve is in the second position.
As an improvement of the invention, the first cartridge valve is provided with a first state that excessive pressure oil of the oil supplementing port overflows back to the oil tank through the valve when the first reversing valve is positioned at the second position and is opened when the pressure of the pressure oil of the oil supplementing port is larger than the pressure of the spring cavity of the overflow valve when the first reversing valve is positioned at the second position.
As a further improvement of the invention, a shuttle valve is also arranged for selecting the pressure oil of the closed pump interface or the control port and outputting the pressure oil to the second cartridge valve control cavity or the third cartridge valve control cavity through the second reversing valve.
As a further improvement of the invention, an orifice is arranged between the shuttle valve and the second reversing valve.
As a further improvement of the invention, the first reversing valve and the second reversing valve are both electromagnetic reversing valves.
As a further improvement of the invention, the first reversing valve is a two-position three-way reversing valve, and the second reversing valve is a two-position four-way reversing valve.
As a further improvement of the invention, the first cartridge valve, the second cartridge valve and the third cartridge valve are two-way cartridge valves.
As a further improvement of the invention, the pressure measuring ports are arranged at the oil supplementing port, the closed pump port and the working port.
The control method adopts the oil supplementing switching valve, and the control method for controlling the switching between the closed system and the open system is as follows:
(1) when the first reversing valve is electrified for reversing and the second reversing valve is electrified for reversing, the first reversing valve and the second reversing valve are both in a second position, at the moment, the first cartridge valve control cavity is used for oil return through the overflow valve, the second cartridge valve control cavity is connected with the oil tank, the second cartridge valve is opened by the pressure oil of the oil supplementing port, so that the second cartridge valve is in an opened first position, the maximum value of the oil pressure of the pressure oil output by the oil supplementing port is the set pressure of the spring cavity of the overflow valve, the redundant flow is fed back to the oil tank through the first cartridge valve, the third cartridge valve is in a closed second position, at the moment, the closed pump interface is communicated with the low-pressure oil port of the closed pump, and the pressure oil of the oil supplementing port is fed to the closed pump interface through the second cartridge valve, so that the closed pump is used as an oil source of an open system through the oil supplementing port.
(2) When the first reversing valve is not electrified and the second reversing valve is not electrified, the first reversing valve and the second reversing valve are both in a first position, the first cartridge valve control cavity is directly connected with the oil tank to unload the oil supplementing pump at the oil supplementing port, the second cartridge valve is in a second closed position, the third cartridge valve control cavity is connected with the oil tank, the third cartridge valve is opened by pressure oil of the closed pump port and is communicated with the working port through the third cartridge valve to form a closed loop, and at the moment, the closed pump port is communicated with the high-pressure oil port of the closed pump.
The invention has the beneficial effects that the oil supplementing port switching valve is arranged in the system, the closed system control and the open system control can be performed through the position change of the reversing valve and the cartridge valve, and the control mode can be rapidly switched when the structure is not changed, so that the oil supply of the product is reliable, the energy consumption is low, the response is rapid, the number of variable pumps can be reduced in the system, and the production cost is reduced. The invention also has the advantages of convenient control, reliable switching, low cost, stable performance, long service life and the like.
Drawings
Fig. 1 is a hydraulic schematic of an embodiment of the present invention.
In the figure, 1, a first reversing valve; 2. a second reversing valve; 3. an overflow valve; 4. a first cartridge valve; 41. a choke; 5. a second cartridge valve; 6. a third cartridge valve; 7. a shuttle valve; 71. an orifice; a1, a closed pump interface; a2, a working interface; K. a control port; p, an oil supplementing port.
Detailed Description
Embodiments of the invention are further described below with reference to the accompanying drawings:
the oil supplementing switching valve for switching between closed and open systems is shown in fig. 1, and comprises a first reversing valve 1, a second reversing valve 2, an overflow valve 3, a first cartridge valve 4, a second cartridge valve 5, a third cartridge valve 6, an oil supplementing port P, a closed pump port A1 and a working port A2;
the first reversing valve is used for connecting the first cartridge valve control cavity with the first position of the oil tank and connecting the first cartridge valve control cavity with the oil inlet of the overflow valve;
the second reversing valve is used for sealing the pressure oil of the second cartridge valve control cavity, connecting the third cartridge valve control cavity with the oil tank, and connecting the second cartridge valve control cavity with the oil tank, and sealing the pressure oil of the third cartridge valve control cavity;
the first cartridge valve is characterized in that an oil inlet of the first cartridge valve is connected with an oil supplementing port, an oil outlet of the first cartridge valve is connected with an oil tank, and a throttle port 41 is arranged between the oil inlet of the first cartridge valve and a control cavity of the first cartridge valve;
the second cartridge valve is opened when the first reversing valve is in the second position and the second reversing valve is in the second position, so that the pressure oil of the oil supplementing port is connected with the closed pump interface through the second cartridge valve to form a first position controlled by the open system, and the second position is closed when the first reversing valve is in the first position and/or the second reversing valve is in the first position;
and the third cartridge valve is opened when the second reversing valve is in the first position, so that the pressure oil of the closed pump interface is connected with the working interface through the third cartridge valve to realize the first position of closed system control, and the second valve is closed when the second reversing valve is in the second position. The invention has the beneficial effects that the oil supplementing port switching valve is arranged in the system, the closed system control and the open system control can be performed through the position change of the reversing valve and the cartridge valve, and the control mode can be rapidly switched when the structure is not changed, so that the oil supply of the product is reliable, the energy consumption is low, the response is rapid, the number of variable pumps can be reduced in the system, and the production cost is reduced. The invention also has the advantages of convenient control, reliable switching, low cost, stable performance, long service life and the like. Specifically, the closed pump can be used as an open system oil source to be switched with a closed system loop, so that the system can realize volume speed regulation without throttling loss, and meanwhile, the invention has the characteristics of low cost and high response speed. In practical crane hydraulic systems, the number of pumps can also be reduced, thereby reducing production costs.
The first cartridge valve is provided with a first state that redundant pressure oil of an oil supplementing port flows back to the oil tank through the valve when the first reversing valve is positioned at a second position for supplementing oil, and a second state that the pressure of the pressure oil of the oil supplementing port is larger than the pressure of a spring cavity of the overflow valve when the first reversing valve is positioned at the second position. Specifically, when the first reversing valve is at the first position, the first cartridge valve control cavity is directly connected with the oil tank, the first cartridge valve can be opened only by pressure oil, the pressure loss is small, and the system performs closed control when the first reversing valve is at the first position, and oil supplementing is not needed, so that the oil supplementing pump can not work.
The invention is also provided with a shuttle valve 7 which is used for selecting the pressure oil of the closed pump interface A1 or the control port K and outputting the pressure oil to the second cartridge valve control cavity or the third cartridge valve control cavity through the second reversing valve. Thus, the second cartridge valve or the third cartridge valve can be reliably closed regardless of whether the closed pump port has output pressure oil.
An orifice 71 is provided between the shuttle valve and the second reversing valve. Thus, the impact force of the cartridge valve control chamber can be reduced.
The first reversing valve and the second reversing valve are electromagnetic reversing valves. Specifically, the first reversing valve is a two-position three-way reversing valve, and the second reversing valve is a two-position four-way reversing valve. Such a structure makes product control reliable.
The first cartridge valve, the second cartridge valve and the third cartridge valve are two-way cartridge valves. Specifically, the first cartridge valve is provided with the throttle on the valve core, so that the oil can directly flow to the first cartridge valve control cavity when the oil is fed into the oil supplementing port, the opening pressure of the first cartridge valve can be adjusted, and the output pressure of the oil supplementing port in the open system can be adjusted by adjusting the pressure of the spring cavity of the overflow valve.
And pressure measuring ports are arranged at the oil supplementing port, the closed pump port and the working port. In the drawings, the pressure measuring port is denoted by M, and the pressure measuring port at the oil supplementing port is denoted by MP.
The control method adopts the oil supplementing switching valve, and the control method for controlling the switching between the closed system and the open system is as follows:
(1) when the first reversing valve 1 is electrified and the second reversing valve 2 is electrified and reversed, the first reversing valve 1 and the second reversing valve 2 are both in the second position, at the moment, the control cavity of the first cartridge valve 4 is used for oil return through the overflow valve 3, the control cavity of the second cartridge valve 5 is connected with an oil tank, the pressure oil of the oil supplementing port P opens the second cartridge valve 5 to enable the second cartridge valve 5 to be in the first opened position, the maximum value of the oil pressure of the pressure oil output by the oil supplementing port P is the set pressure of the spring cavity of the overflow valve 3, redundant flow returns to the oil tank through the first cartridge valve 4, the third cartridge valve 6 is in the second closed position, at the moment, the closed pump interface A1 is communicated with the low pressure oil port of the closed pump, at the moment, the pressure oil of the oil supplementing port P is used as an oil source of an open system through the oil supplementing port P.
(2) When the first reversing valve 1 is not electrified and the second reversing valve 2 is not electrified, the first reversing valve 1 and the second reversing valve 2 are both in the first position, the control cavity of the first cartridge valve 4 is directly connected with the oil tank to unload the oil supplementing pump at the oil supplementing port P, and the oil supplementing pump can not work at the moment in the actual working process. The second cartridge valve 5 is in a closed second position, the control cavity of the third cartridge valve 6 is connected with the oil tank, the pressure oil of the closed pump interface A1 opens the third cartridge valve 6 and is communicated with the working interface A2 through the third cartridge valve 6 to form a closed loop, and at the moment, the closed pump interface A1 is communicated with the high-pressure oil port of the closed pump.
In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art. Furthermore, in the description of the present invention, unless otherwise indicated, the meaning of "a plurality" is two or more.
The skilled person will know: while the invention has been described in terms of the foregoing embodiments, the inventive concepts are not limited to the invention, and any modifications that use the inventive concepts are intended to be within the scope of the appended claims.
Claims (9)
1. The oil supplementing switching valve for switching between closed and open systems is characterized by comprising a first reversing valve, a second reversing valve, an overflow valve, a first cartridge valve, a second cartridge valve, a third cartridge valve, an oil supplementing port, a closed pump interface and a working interface;
the first reversing valve is used for connecting the first cartridge valve control cavity with the first position of the oil tank and connecting the first cartridge valve control cavity with the oil inlet of the overflow valve;
the second reversing valve is used for sealing the pressure oil of the second cartridge valve control cavity, connecting the third cartridge valve control cavity with the oil tank, and connecting the second cartridge valve control cavity with the oil tank, and sealing the pressure oil of the third cartridge valve control cavity;
the first cartridge valve is characterized in that an oil inlet of the first cartridge valve is connected with an oil supplementing port, an oil outlet of the first cartridge valve is connected with an oil tank, and a throttling port is arranged between the oil inlet of the first cartridge valve and a control cavity of the first cartridge valve;
the second cartridge valve is opened when the first reversing valve is in the second position and the second reversing valve is in the second position, so that the pressure oil of the oil supplementing port is connected with the closed pump interface through the second cartridge valve to form a first position controlled by the open system, and the second position is closed when the first reversing valve is in the first position and/or the second reversing valve is in the first position;
and the third cartridge valve is opened when the second reversing valve is in the first position, so that the pressure oil of the closed pump interface is connected with the working interface through the third cartridge valve to realize the first position of closed system control, and the second valve is closed when the second reversing valve is in the second position.
2. The oil supply switching valve for switching between closed and open systems according to claim 1, wherein the first cartridge valve has a first state in which excess oil at the oil supply port is returned to the oil tank through the valve when the first direction valve is in the second position for system oil supply, and a second state in which the first direction valve is opened when the pressure of the oil at the oil supply port is greater than the pressure of the spring chamber of the relief valve.
3. The oil supply switching valve for switching between closed and open systems according to claim 1, further comprising a shuttle valve for selecting a closed pump port or control port pressure oil and outputting the oil to the second cartridge valve control chamber or the third cartridge valve control chamber through the second reversing valve.
4. A make-up switching valve for switching between closed and open systems as defined in claim 3 wherein an orifice is provided between said shuttle valve and said second reversing valve.
5. The oil compensating switching valve for switching between closed and open systems according to claim 1, wherein the first and second reversing valves are electromagnetic reversing valves.
6. The oil compensating switching valve for switching between closed and open systems according to claim 1, wherein the first switching valve is a two-position three-way switching valve and the second switching valve is a two-position four-way switching valve.
7. The oil supply switching valve for switching between closed and open systems according to claim 1, wherein the first, second and third cartridge valves are two-way cartridge valves.
8. The oil compensating switching valve for switching between closed and open systems according to claim 1, wherein the oil compensating port, the closed pump port and the working port are provided with pressure measuring ports.
9. A control method, characterized in that: an oil supplementing switching valve for switching a closed system and an open system according to any one of claims 1 to 8, wherein the control method for controlling the switching of the closed system and the open system is as follows:
(1) when the first reversing valve is electrified for reversing and the second reversing valve is electrified for reversing, the first reversing valve and the second reversing valve are both in a second position, at the moment, the first cartridge valve control cavity is used for oil return through the overflow valve, the second cartridge valve control cavity is connected with the oil tank, the second cartridge valve is opened by the pressure oil of the oil supplementing port to enable the second cartridge valve to be in an opened first position, the maximum value of the oil pressure of the pressure oil output by the oil supplementing port is the set pressure of the spring cavity of the overflow valve, the redundant flow is fed back to the oil tank through the first cartridge valve, the third cartridge valve is in a closed second position, at the moment, the closed pump interface is communicated with the low pressure oil port of the closed pump, and the pressure oil of the oil supplementing port is fed to the closed pump interface through the second cartridge valve, at the moment, and the closed pump is used as an oil source of an open system through the oil supplementing port;
(2) when the first reversing valve is not electrified and the second reversing valve is not electrified, the first reversing valve and the second reversing valve are both in a first position, the first cartridge valve control cavity is directly connected with the oil tank to unload the oil supplementing pump at the oil supplementing port, the second cartridge valve is in a second closed position, the third cartridge valve control cavity is connected with the oil tank, the third cartridge valve is opened by pressure oil of the closed pump port and is communicated with the working port through the third cartridge valve to form a closed loop, and at the moment, the closed pump port is communicated with the high-pressure oil port of the closed pump.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810660602.8A CN108533556B (en) | 2018-06-25 | 2018-06-25 | Oil supplementing switching valve for switching closed system and open system and control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810660602.8A CN108533556B (en) | 2018-06-25 | 2018-06-25 | Oil supplementing switching valve for switching closed system and open system and control system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108533556A CN108533556A (en) | 2018-09-14 |
| CN108533556B true CN108533556B (en) | 2024-04-09 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810660602.8A Active CN108533556B (en) | 2018-06-25 | 2018-06-25 | Oil supplementing switching valve for switching closed system and open system and control system |
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| CN (1) | CN108533556B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109681481B (en) * | 2019-02-01 | 2021-02-09 | 徐州重型机械有限公司 | Oil supply system, hydraulic control system and engineering machinery |
| CN112879391B (en) * | 2021-02-20 | 2023-04-18 | 潍柴动力股份有限公司 | Oil supplementing device and closed system |
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| CN203906448U (en) * | 2014-05-29 | 2014-10-29 | 四川工程职业技术学院 | Hydraulic component performance testing system |
| CN104307953A (en) * | 2014-08-29 | 2015-01-28 | 武汉华夏精冲技术有限公司 | Multistage unloading loop control system for large-tonnage full-automatic hydraulic fine blanking press |
| CN104632746A (en) * | 2015-03-04 | 2015-05-20 | 徐州重型机械有限公司 | Switching valve, switching hydraulic system and crane |
| CN105090154A (en) * | 2015-08-26 | 2015-11-25 | 徐工集团工程机械股份有限公司科技分公司 | Unloading valve block, opening and closing core hydraulic system and engineering machine |
| CN208503126U (en) * | 2018-06-25 | 2019-02-15 | 圣邦集团有限公司 | A kind of repairing switching valve for enclosed and open system switching |
-
2018
- 2018-06-25 CN CN201810660602.8A patent/CN108533556B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203906448U (en) * | 2014-05-29 | 2014-10-29 | 四川工程职业技术学院 | Hydraulic component performance testing system |
| CN104307953A (en) * | 2014-08-29 | 2015-01-28 | 武汉华夏精冲技术有限公司 | Multistage unloading loop control system for large-tonnage full-automatic hydraulic fine blanking press |
| CN104632746A (en) * | 2015-03-04 | 2015-05-20 | 徐州重型机械有限公司 | Switching valve, switching hydraulic system and crane |
| CN105090154A (en) * | 2015-08-26 | 2015-11-25 | 徐工集团工程机械股份有限公司科技分公司 | Unloading valve block, opening and closing core hydraulic system and engineering machine |
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| CN108533556A (en) | 2018-09-14 |
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