CN112747139B - Reversing valve for preventing oil cylinder from creeping - Google Patents
Reversing valve for preventing oil cylinder from creeping Download PDFInfo
- Publication number
- CN112747139B CN112747139B CN202110022064.1A CN202110022064A CN112747139B CN 112747139 B CN112747139 B CN 112747139B CN 202110022064 A CN202110022064 A CN 202110022064A CN 112747139 B CN112747139 B CN 112747139B
- Authority
- CN
- China
- Prior art keywords
- oil
- hole
- sealing surface
- working oil
- port
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000007789 sealing Methods 0.000 claims abstract description 64
- 230000007935 neutral effect Effects 0.000 claims description 8
- 238000004519 manufacturing process Methods 0.000 abstract description 4
- 239000003921 oil Substances 0.000 description 143
- 238000000034 method Methods 0.000 description 5
- 239000010687 lubricating oil Substances 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 230000009193 crawling Effects 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000007599 discharging Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000010720 hydraulic oil Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000008093 supporting effect Effects 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
Classifications
-
- 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
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K11/00—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves
- F16K11/02—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit
- F16K11/06—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements
- F16K11/065—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements with linearly sliding closure members
- F16K11/07—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with all movable sealing faces moving as one unit comprising only sliding valves, i.e. sliding closure elements with linearly sliding closure members with cylindrical slides
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Magnetically Actuated Valves (AREA)
- Multiple-Way Valves (AREA)
Abstract
The invention provides a reversing valve capable of preventing oil cylinder from creeping, and belongs to the field of reversing valve manufacturing; the invention comprises the following steps: a housing and a valve core; the shell is internally provided with a high-pressure oil port, two different working oil ports and two oil return ports; the two working oil ports are respectively arranged at two sides of the high-pressure oil port and are positioned between the two oil return ports; a working oil hole is respectively arranged between the high-pressure oil port and the two working oil ports, and an oil return hole is arranged between each working oil port and the adjacent oil return port; the valve core is slidably sleeved in the shell; the valve core slides to one side so as to open the working oil hole on the side and open the oil return hole on the other side; the valve core is provided with two shoulder sealing surfaces; the left side and the right side of each shoulder sealing surface are respectively used for sealing the working oil hole and the oil return hole; when the valve core is in the middle state, the contact area of the shoulder sealing surface and the working oil hole is larger than the contact area of the shoulder sealing surface and the oil return hole. The reversing valve for preventing the oil cylinder from creeping reduces the sealing length of the oil return hole, so that an executing element connected with the working oil port cannot influence the current position of the executing element due to hydraulic pressure built by internal leakage, and the reversing valve is very suitable for occasions with requirements on the position of the executing element.
Description
Technical Field
The invention relates to a valve manufacturing technology, in particular to a reversing valve capable of preventing oil cylinder from creeping, and belongs to the technical field of hydraulic equipment manufacturing.
Background
The reversing valve is very commonly applied as a hydraulic element for controlling the on-off and reversing of an oil way. The common reversing valve is of a slide valve type structure, a valve core of the common reversing valve slides in a valve body, and different oil ports are communicated or closed through reversing of the switching valve core.
In the prior art, when the reversing valve core is in the middle position, the P/A/B/T is not communicated (the high-pressure oil port is not communicated with the working oil port), and when the internal leakage exists, the pressure oil in the main oil path leaks into the working oil port of the reversing valve through an annular sealing gap between the reversing valve core and the valve body, and because the sealing oil lengths of the valve core step and the valve body sealing oil surface are equal, the hydraulic pressure accumulated in the reversing valve cavity A and the reversing valve cavity B are preferably transmitted to a pipeline connected with the working oil port in the loop and respectively enter a rod cavity and a rodless cavity of the oil cylinder, and different hydraulic pressures are established in the two cavities; because of the area difference of the piston of the hydraulic cylinder, when the hydraulic pressure built up by internal leakage reaches or exceeds the static friction enough to overcome the movement of the oil cylinder, the oil cylinder crawls to the right, and the hydraulic cylinder is not applicable to occasions with strict position requirements on an executing element.
Therefore, there is a need in the art for a reversing valve that prevents the cylinder from slowly creeping to the piston side due to high pressure oil penetration when the spool is in the neutral position for a long period of time.
Disclosure of Invention
The invention provides a novel reversing valve for preventing oil cylinder from creeping, which solves the technical problem that an oil cylinder slowly crawls due to high-pressure oil permeation in a neutral state of the reversing valve in the prior art by changing and reducing the sealing length of an oil return hole.
The reversing valve for preventing oil cylinder creeping comprises: a housing and a valve core; the shell is internally provided with a high-pressure oil port, two different working oil ports and two oil return ports;
The two working oil ports are respectively arranged at two sides of the high-pressure oil port and are positioned between the two oil return ports; a working oil hole is respectively arranged between the high-pressure oil port and the two working oil ports, and an oil return hole is arranged between each working oil port and the adjacent oil return port;
The valve core is slidably sleeved in the shell; the valve core slides to one side so as to open the working oil hole on the side and open the oil return hole on the other side;
The valve core is provided with two shoulder sealing surfaces; the left side and the right side of each shoulder sealing surface are respectively used for sealing the working oil hole and the oil return hole;
When the valve core is in the middle state, the contact area of the shoulder sealing surface and the working oil hole is larger than the contact area of the shoulder sealing surface and the oil return hole.
The reversing valve for preventing oil cylinder creeping is characterized in that the contact surface of the shoulder sealing surface and the working oil hole is a first sealing surface;
a buffer groove is formed in the first sealing surface; the buffer groove is a groove with a semicircular horizontal section, and one side of the circular arc of the buffer groove faces the working oil hole.
The reversing valve for preventing oil cylinder from creeping is characterized in that the contact surface of the shoulder sealing surface and the oil return hole is a second sealing surface;
An oil return buffer groove is formed in the second sealing surface; the oil return buffer groove is a groove with a semicircular horizontal section, and one side of the circular arc of the oil return buffer groove faces the working oil hole.
The reversing valve for preventing the oil cylinder from creeping is characterized in that a plurality of lubricating oil grooves are further formed in two shoulder sealing surfaces.
The reversing valve for preventing oil cylinder from creeping is characterized in that an annular slope is further arranged on the edge of the second sealing surface; the annular slope is of a frustum-shaped structure, and one end of the annular slope with a larger diameter is connected with the second sealing surface.
The reversing valve for preventing the oil cylinder from creeping is characterized in that electromagnets are respectively arranged on two sides of the shell, and two ends of each electromagnet are respectively contacted with two ends of the valve core.
The reversing valve for preventing the oil cylinder from creeping is characterized in that the electromagnets are provided with the driving rods, and the electromagnets are connected with the end parts of the valve cores through the driving rods;
and a pre-tightening spring is further arranged between the driving rod and the valve core.
According to the reversing valve for preventing the oil cylinder from creeping, when the execution element with unequal area is driven (such as an oil cylinder with a piston rod at one side, and the like), the sealing area of the oil return hole is smaller; in the shutdown state, once the high-pressure oil in the high-pressure oil port slowly leaks to the working oil port, the high-pressure oil in the working oil port can easily leak to the oil return port, so that the phenomenon of displacement stealing of the actuating element is avoided and improved, and the stable and reliable neutral position of the reversing valve can be effectively ensured.
The reversing valve for preventing the oil cylinder from creeping reduces the sealing length of the oil return hole, so that an executing element connected with the working oil port cannot influence the current position of the executing element due to hydraulic pressure built by internal leakage, and the reversing valve is very suitable for occasions with requirements on the position of the executing element.
Drawings
FIG. 1 is a schematic cross-sectional view of a reversing valve for preventing oil cylinder creep according to an embodiment of the present invention;
FIG. 2 is a schematic view showing a sectional structure of a steering valve for preventing oil cylinder creep in a rightward sliding state according to an embodiment of the present invention;
FIG. 3 is a schematic view of the valve core in FIG. 1;
Fig. 4 is an enlarged schematic view of part of M in fig. 3.
Detailed Description
The reversing valve for preventing the oil cylinder from creeping can be made of the following materials, and is not limited to the following materials, for example: valve core, hydraulic matching system, electric control device and other common components.
FIG. 1 is a schematic cross-sectional view of a reversing valve for preventing oil cylinder creep according to an embodiment of the present invention; FIG. 2 is a schematic view showing a sectional structure of a steering valve for preventing oil cylinder creep in a rightward sliding state according to an embodiment of the present invention; and combines fig. 3 and 4.
The reversing valve for preventing oil cylinder creeping comprises: a housing 1 and a valve core 2; the shell 1 is internally provided with a high-pressure oil port P, two different working oil ports (specifically a working oil port A and a working oil port B) and two oil return ports T.
The two working oil ports (A and B) are respectively arranged at two sides of the high-pressure oil port P and are positioned between the two oil return ports T; the high-pressure oil port P and the two working oil ports (A and B) are respectively provided with a working oil hole 11, and an oil return hole 12 is arranged between each working oil port and the adjacent oil return port.
The valve core 2 is slidably sleeved in the shell 1; the valve core 2 slides to one side so that the working oil hole 11 on the side is opened and the oil return hole 12 on the other side is opened; p is communicated with A to the left, and P is communicated with B to the right, so that high-pressure oil is led to the working oil port, and reversing action is performed.
Two shoulder sealing surfaces are arranged on the valve core 2; the left side and the right side of each shoulder sealing surface are respectively used for sealing the working oil hole and the oil return hole;
When the valve core is in the middle state, the contact area of the shoulder sealing surface and the working oil hole is larger than the contact area of the shoulder sealing surface and the oil return hole.
In general, the high pressure oil port P is connected to a hydraulic pump in a hydraulic system for discharging high pressure hydraulic oil through the high pressure oil pipe P.
The two working oil ports a and B are respectively connected with two ends of an executing element (reversing oil cylinder, in particular to an oil cylinder with a piston or oil cylinder with different areas on two sides in the embodiment) so as to execute reversing action through an oil inlet and outlet pipe.
The return port T is typically connected to a hydraulic tank to facilitate draining low pressure oil to the tank from the non-working side of the actuator. In the working process of the reversing valve, one working oil port is opened, the other working oil port automatically returns oil, and low-pressure oil is discharged into the oil tank.
When no external force acts on the two ends of the valve core, the valve core is in a neutral position, and the oil ports P/A/B/T are not communicated; when the P port is connected with a high-pressure oil source, the high-pressure oil leaks into the cavity A through the axial gap with the longer first sealing surface, and preferably returns to the cavity T through the axial gap with the shorter second sealing surface, so that the cavity A cannot establish hydraulic pressure for driving the oil cylinder to move.
In the embodiment, when the valve core of the reversing valve is in the middle position and the A/B/P/T cavity is in the fully closed state, even if internal leakage still exists in the valve, hydraulic pressure enough to drive the oil cylinder to move cannot be generated in the A cavity and the B cavity, so that the crawling phenomenon of the oil cylinder is eliminated.
In the reversing valve for preventing oil cylinder crawling in this embodiment, a contact surface between the shoulder sealing surface and the working oil hole 11 is a first sealing surface 21; the first sealing surface 21 is provided with a buffer groove 210; the buffer groove 210 is a groove with a semicircular horizontal section, and one side of the arc of the buffer groove 210 faces the working oil hole.
Further, the contact surface between the shoulder sealing surface and the oil return hole 12 is a second sealing surface 22; the second sealing surface 22 is provided with an oil return buffer groove 220; the oil return buffer groove 220 is a groove with a semicircular horizontal section, and one side of the circular arc of the oil return buffer groove 220 faces the working oil hole.
The buffer tank 210 and the oil return buffer tank 220 can avoid the sudden start pressure impact of the reversing valve, the valve core of the reversing valve is added with the buffer tank design, the reliability and the service life of the system are improved, and the quality of the final product is improved.
The reversing valve for preventing oil cylinder creeping in the embodiment, wherein a plurality of lubricating oil grooves 25 are further arranged on two shoulder sealing surfaces. Because most of the lubricating oil groove 25 corresponds to the sealing surface of the sliding hole, the valve core is subjected to the suspension supporting action of oil pressure, the friction force of the valve core in movement is reduced, the hydraulic clamping force of the valve core is reduced, and the reversing valve can be normally reversed when being in a neutral position for a long time.
As shown in fig. 2, the reversing valve for preventing oil cylinder from creeping in the embodiment, wherein an annular slope 23 is further arranged at the edge of the second sealing surface; the annular slope 23 has a frustum-shaped structure, and the end with the larger diameter of the annular slope is connected with the second sealing surface. The annular ramp has a length D and has an included angle C. The horizontal included angle C is generally 10-15 degrees, and the length D is 3-5mm.
In the process of moving the valve core to the right, the annular slope 23 of the second sealing surface 22 opens a small opening first, oil passes through the slope and the oil return buffer groove to enable A to be communicated with T, and oil is discharged from the rodless cavity of the oil cylinder; at the moment, the buffer groove at the left end of the first sealing surface at the right side of the shoulder sealing surface is at a critical position and is not opened; the valve core is opened to the right again, the first sealing surface is opened, and P is communicated with B, and because the valve core is not reversed in place at this time and is communicated only through the buffer groove, the overflow area of the buffer groove is smaller, the oil cylinder slowly moves, and the opening degree is increased along with the valve core to the right, so that the movement of the oil cylinder is gradually and steadily accelerated.
In general, two sides of the housing 1 are respectively provided with an electromagnet, and two ends of the electromagnets are respectively contacted with two ends of the valve core 2.
Specifically, the electromagnets are all provided with driving rods, and the electromagnets are connected with the end parts of the valve cores through the driving rods;
A pre-tightening spring is also arranged between the driving rod and the valve core 2. The pretension spring can keep the valve core at a neutral position without external force.
According to the reversing valve for preventing the oil cylinder from creeping, when the execution element with unequal area is driven (such as an oil cylinder with a piston rod at one side, and the like), the sealing area of the oil return hole is smaller; in the shutdown state, once the high-pressure oil in the high-pressure oil port slowly leaks to the working oil port, the high-pressure oil in the working oil port can easily leak to the oil return port, so that the phenomenon of displacement stealing of the actuating element is avoided and improved, and the stable and reliable neutral position of the reversing valve can be effectively ensured.
The reversing valve for preventing the oil cylinder from creeping reduces the sealing length of the oil return hole, so that an executing element connected with the working oil port cannot influence the current position of the executing element due to hydraulic pressure built by internal leakage, and the reversing valve is very suitable for occasions with requirements on the position of the executing element.
In addition, the reversing valve for preventing the oil cylinder from creeping is low in manufacturing cost, compact in structural design, ingenious in structure, stable in starting and stopping, convenient to use and maintain, and suitable for implementation of reversing actions of hydraulic systems with different hydraulic stress areas on two sides of an executive component in various two-side working oil ports.
The foregoing embodiment numbers of the present invention are merely for the purpose of description, and do not represent the advantages or disadvantages of the embodiments. From the description of the above embodiments, it will be apparent to those skilled in the art that the above example methods may be implemented by means of a superposition of some variants plus the necessary general techniques; of course, the method can also be realized by simplifying some important technical features. Based on such understanding, the technical solution of the present invention essentially or partly contributes to the prior art is: overall function and construction, and in combination with the construction described in connection with the various embodiments of the invention.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.
Claims (4)
1. A reversing valve for preventing oil cylinder creep, comprising: a housing and a valve core; the shell is internally provided with a high-pressure oil port, two different working oil ports and two oil return ports;
The two working oil ports are respectively arranged at two sides of the high-pressure oil port and are positioned between the two oil return ports; a working oil hole is respectively arranged between the high-pressure oil port and the two working oil ports, and an oil return hole is arranged between each working oil port and the adjacent oil return port; the two working oil ports are respectively connected with two ends of the oil cylinder;
The valve core is slidably sleeved in the shell; the valve core slides to one side so as to open the working oil hole on the side and open the oil return hole on the other side;
The valve core is provided with two shoulder sealing surfaces; the left side and the right side of each shoulder sealing surface are respectively used for sealing the working oil hole and the oil return hole;
When the valve core is in the middle state, the contact area of the shoulder sealing surface and the working oil hole is larger than the contact area of the shoulder sealing surface and the oil return hole;
the contact surface of the shoulder sealing surface and the working oil hole is a first sealing surface; a buffer groove is formed in the first sealing surface; the buffer groove is a groove with a semicircular horizontal section, and one side of the circular arc of the buffer groove faces the working oil hole;
The contact surface of the shoulder sealing surface and the oil return hole is a second sealing surface; an oil return buffer groove is formed in the second sealing surface; the oil return buffer groove is a groove with a semicircular horizontal section, and one side of the circular arc of the oil return buffer groove faces the working oil hole;
The edge of the second sealing surface is also provided with an annular slope; the annular slope is of a frustum-shaped structure, and one end of the annular slope with a larger diameter is connected with the second sealing surface;
When no external force acts on the two ends of the valve core, the valve core is in a neutral position, and at the moment, the high-pressure oil port is not communicated with the working oil port, and the working oil port is not communicated with the oil return port; when the high-pressure oil port is connected with a high-pressure oil source, the high-pressure oil leaks to one of the working oil ports through the axial gap of the first sealing surface and returns to one of the oil return ports through the axial gap of the second sealing surface, so that the working oil port cannot establish hydraulic pressure for driving the oil cylinder to move.
2. The reversing valve for preventing oil cylinder creep according to claim 1, wherein a plurality of oil grooves are further provided on both of the shoulder seal surfaces.
3. The reversing valve for preventing oil cylinder creep according to claim 1, wherein two sides of the housing are respectively provided with an electromagnet, and two ends of the two electromagnets are respectively contacted with two ends of the valve core.
4. The reversing valve for preventing oil cylinder creep according to claim 3, wherein the electromagnets are provided with driving rods, and the electromagnets are connected with the end parts of the valve cores through the driving rods;
and a pre-tightening spring is further arranged between the driving rod and the valve core.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110022064.1A CN112747139B (en) | 2021-01-08 | 2021-01-08 | Reversing valve for preventing oil cylinder from creeping |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110022064.1A CN112747139B (en) | 2021-01-08 | 2021-01-08 | Reversing valve for preventing oil cylinder from creeping |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112747139A CN112747139A (en) | 2021-05-04 |
| CN112747139B true CN112747139B (en) | 2024-06-04 |
Family
ID=75650294
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110022064.1A Active CN112747139B (en) | 2021-01-08 | 2021-01-08 | Reversing valve for preventing oil cylinder from creeping |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112747139B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113309754A (en) * | 2021-05-26 | 2021-08-27 | 涌镇液压机械（上海）有限公司 | Valve core structure of proportional reversing valve |
| CN113944778A (en) * | 2021-10-16 | 2022-01-18 | 涌镇液压机械（上海）有限公司 | Valve core structure of proportional valve |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB665800A (en) * | 1948-11-29 | 1952-01-30 | Bendix Aviat Corp | A hydraulic power system and sequence valve therefor |
| US4204459A (en) * | 1978-04-19 | 1980-05-27 | Caterpillar Tractor Co. | Combination check and flow control valve for hydraulic systems |
| CN201090548Y (en) * | 2007-09-21 | 2008-07-23 | 兰州理工大学 | Vibration damping type hydraulic ratio control main valve |
| CN203963117U (en) * | 2014-07-08 | 2014-11-26 | 嘉兴米克气动设备有限公司 | Two-position-five-way solenoid valve |
| CN205064924U (en) * | 2015-09-25 | 2016-03-02 | 比亚迪股份有限公司 | Control valve, multiple unit valve and fork truck |
| CN105757033A (en) * | 2016-05-05 | 2016-07-13 | 浙江亿洋工具制造有限公司 | Digital control valve and control method thereof for controlling speed ring and position ring of oil cylinder |
| CN208087097U (en) * | 2017-12-28 | 2018-11-13 | 徐工集团工程机械有限公司 | The variable amplitude hydraulic system and lorry-mounted crane of crane |
| CN108980129A (en) * | 2018-07-24 | 2018-12-11 | 中国航空工业集团公司西安飞行自动控制研究所 | A kind of load holding control valve |
-
2021
- 2021-01-08 CN CN202110022064.1A patent/CN112747139B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB665800A (en) * | 1948-11-29 | 1952-01-30 | Bendix Aviat Corp | A hydraulic power system and sequence valve therefor |
| US4204459A (en) * | 1978-04-19 | 1980-05-27 | Caterpillar Tractor Co. | Combination check and flow control valve for hydraulic systems |
| CN201090548Y (en) * | 2007-09-21 | 2008-07-23 | 兰州理工大学 | Vibration damping type hydraulic ratio control main valve |
| CN203963117U (en) * | 2014-07-08 | 2014-11-26 | 嘉兴米克气动设备有限公司 | Two-position-five-way solenoid valve |
| CN205064924U (en) * | 2015-09-25 | 2016-03-02 | 比亚迪股份有限公司 | Control valve, multiple unit valve and fork truck |
| CN105757033A (en) * | 2016-05-05 | 2016-07-13 | 浙江亿洋工具制造有限公司 | Digital control valve and control method thereof for controlling speed ring and position ring of oil cylinder |
| CN208087097U (en) * | 2017-12-28 | 2018-11-13 | 徐工集团工程机械有限公司 | The variable amplitude hydraulic system and lorry-mounted crane of crane |
| CN108980129A (en) * | 2018-07-24 | 2018-12-11 | 中国航空工业集团公司西安飞行自动控制研究所 | A kind of load holding control valve |
Non-Patent Citations (2)
| Title |
|---|
| 张立秀 ; .液压换向阀中位过渡机能对挖掘机可控性和冲击振动的影响.液压与气动.第64-67页. * |
| 滑阀式气自动控制技术;拖拉机与农用运输车;19750815(04);第37-47页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112747139A (en) | 2021-05-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112747139B (en) | Reversing valve for preventing oil cylinder from creeping | |
| WO2021121170A1 (en) | Electro-hydraulic control valve for hydraulic operating mechanism, and electromagnetic pilot valve and pilot valve thereof | |
| KR20130103304A (en) | Double check valve for construction equipment | |
| KR101061192B1 (en) | Heavy Equipment Hydraulic Control Valve | |
| CN214699327U (en) | Reversing valve capable of improving load action stability | |
| CN112392789B (en) | Hydraulic control valve, hydraulic operating mechanism using same and circuit breaker | |
| CN113418023B (en) | Reversing valve capable of being switched at high frequency | |
| CN112555218B (en) | Valve body structure of reversing valve | |
| CN111365313B (en) | Valve core friction force compensation hydraulic valve under centrifugal environment | |
| CN214331566U (en) | Reversing valve capable of preventing displacement of actuating element | |
| CN214500132U (en) | Reversing valve capable of being switched at high frequency | |
| CN214248394U (en) | Reversing valve capable of preventing oil cylinder from creeping | |
| CN112746999B (en) | Leakage type reversing valve | |
| CN113431924A (en) | Reversing valve capable of preventing displacement of actuating element | |
| CN213899453U (en) | Valve body structure of reversing valve | |
| CN113958726B (en) | Valve core structure of internal flow reversing valve | |
| CN217354975U (en) | Pilot cushion valve, hydraulic control loop and engineering machinery | |
| CN113446416A (en) | Reversing valve capable of improving load action stability | |
| CN214247839U (en) | External leakage type reversing valve | |
| CN216078407U (en) | Valve core structure of inward flow type reversing valve | |
| CN215445168U (en) | Reversing valve with sewage discharge capacity | |
| CN115750500A (en) | Normally closed type pilot control constant-ratio pressure reduction overflow valve | |
| CN113483117A (en) | Reversing valve | |
| JP6564225B2 (en) | Control valve | |
| CN112797189A (en) | Reversing valve with sewage discharge capacity |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |