CN112797188B - Valve core structure of proportional reversing valve - Google Patents
Valve core structure of proportional reversing valve Download PDFInfo
- Publication number
- CN112797188B CN112797188B CN202110123635.0A CN202110123635A CN112797188B CN 112797188 B CN112797188 B CN 112797188B CN 202110123635 A CN202110123635 A CN 202110123635A CN 112797188 B CN112797188 B CN 112797188B
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- valve core
- valve
- sliding hole
- proportional reversing
- control oil
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- 238000007789 sealing Methods 0.000 claims abstract description 18
- 238000005461 lubrication Methods 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 8
- 238000004364 calculation method Methods 0.000 abstract description 6
- 238000005520 cutting process Methods 0.000 abstract description 4
- 238000013461 design Methods 0.000 abstract description 4
- 239000003921 oil Substances 0.000 description 42
- 230000009471 action Effects 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 239000010720 hydraulic oil Substances 0.000 description 3
- 239000010687 lubricating oil Substances 0.000 description 3
- 230000007935 neutral effect Effects 0.000 description 3
- 230000008859 change Effects 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000018109 developmental process Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000032683 aging Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000002146 bilateral effect Effects 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000008569 process 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
- 238000012360 testing method Methods 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
- 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
- F16K3/00—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing
- F16K3/30—Details
- F16K3/36—Features relating to lubrication
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Multiple-Way Valves (AREA)
Abstract
The invention provides a valve core structure of a proportional reversing valve, and belongs to the field of reversing valve manufacturing; the valve core is slidably arranged in a shell, a high-pressure oil port and at least one working oil port are arranged in the shell, a sliding hole is formed in the shell, and the valve core is sleeved in the sliding hole and seals the sliding hole through the radial surface of the valve core; the valve core slides so that a gap is formed between the radial end surface of the valve core and the sliding hole, and the gap is used for communicating the high-pressure oil port and the working oil port; when the valve core is positioned in the middle position, the surface of the valve core, which is contacted with the sliding hole, is a shoulder sealing surface; the valve core is also provided with a plurality of groups of reducing conical tables, and each group of reducing conical tables comprises at least two circular tables which are connected and have different slope of the inclined plane; and a group of reducing conical tables are respectively arranged on two sides of the shoulder sealing surface. The invention is manufactured by adopting the cutting process of the circular slope surrounding the outer circle of the valve core, and can be directly machined by turning, and the manufacturing process is simple; because the valve core adopts the design of the diameter-variable round table, when the valve core slides, the calculation of the overflow area is simple, and the flow passing through the valve core can be calculated rapidly.
Description
Technical Field
The invention relates to a valve manufacturing technology, in particular to a valve core structure of a proportional reversing valve, 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.
The opening of the valve core of the proportional reversing valve can be changed along with the change of the control command, so that the continuous adjustment of the movement speed of the executive component can be realized by adjusting the excessive flow of the proportional reversing valve, the control is simple and convenient, and the control precision is high; in order to enable the flow to be controllable, a valve core of the proportional reversing valve is provided with a plurality of throttling grooves, and the overflow of the proportional reversing valve can be continuously adjusted by controlling the opening size of the throttling grooves; the throttling grooves can be designed into various types such as triangle, U-shaped, rectangle and the like according to different application conditions, and the cost of the proportional reversing valve is high due to the high processing difficulty and complex processing technology of the throttling grooves; when designing the throttling groove, because the throttling groove is special, the size of the flow area of the throttling groove is complex when calculating the opening degree of the valve core, and the theoretical calculation and the actual test are often quite different, so that the development time of the proportional reversing valve is slow.
Therefore, the valve core in the prior art is inconvenient to calculate the passing flow, and the calculation error and the error between actual applications are large.
Disclosure of Invention
The invention provides a valve core structure of a novel proportional reversing valve, which solves the technical problem that the flow is difficult to accurately calculate in the valve core opening state in the prior art by designing a reducing round table at the edge of the sealing end surface of the valve core.
The valve core structure of the proportional reversing valve is slidably arranged in a shell, a high-pressure oil port and at least one working oil port are arranged in the shell, a sliding hole is formed in the shell, and the valve core is sleeved in the sliding hole and seals the sliding hole through the radial surface of the valve core; the valve core slides so that a gap is formed between the radial end surface of the valve core and the sliding hole, and the gap is used for communicating the high-pressure oil port and the working oil port;
when the valve core is positioned in the middle position, the surface of the valve core, which is contacted with the sliding hole, is a shoulder sealing surface; the valve core is also provided with a plurality of groups of reducing conical tables, and each group of reducing conical tables comprises at least two circular tables which are connected and have different slope of the inclined plane; and a group of reducing conical tables are respectively arranged on two sides of the shoulder sealing surface.
The valve core structure of the proportional reversing valve is characterized in that a plurality of lubricating oil grooves are formed in the shoulder sealing surfaces.
The valve core structure of the proportional reversing valve, wherein the reducing round table comprises: the first round platform is tightly connected with the sealing surface of the shoulder, and the second round platform is tightly connected with the first round platform;
the slope of the second round table is larger than that of the first round table; the maximum diameter of the first round platform is smaller than the diameter of the shoulder sealing surface.
The valve core structure of the proportional reversing valve is of a bilateral symmetry structure, and is provided with two axial end faces which correspond to each other.
The valve core structure of the proportional reversing valve, wherein the reducing round table comprises: a third round table; the third round table is adjacent to the second round table.
The valve core structure of the proportional reversing valve is characterized in that control oil ways are respectively arranged on two sides of the shell, and two ends of the control oil ways are respectively contacted with two ends of the valve core.
The valve core structure of the proportional reversing valve is characterized in that two control oil cavities are arranged in the shell, and the two control oil cavities are respectively connected with the control oil circuit; two ends of the valve core are respectively positioned in the two control oil cavities; the control oil way drives the valve core to slide through the control oil cavity;
and a pre-tightening spring contacted with the valve core is further arranged in the control oil cavity.
The invention is manufactured by adopting the cutting process of the circular slope surrounding the outer circle of the valve core, and can be directly machined by turning, and the manufacturing process is simple; because the valve core adopts the design of the diameter-variable round table, when the valve core slides, the calculation of the overflow area is simple, and the flow passing through the valve core can be calculated rapidly.
Drawings
FIG. 1 is a schematic view of a cross-sectional structure of a valve core structure of a proportional reversing valve according to an embodiment of the present invention in a neutral state;
FIG. 2 is an enlarged partial schematic view of N in FIG. 1;
Fig. 3 is another schematic structure of fig. 2.
Detailed Description
The valve core structure of the proportional reversing valve 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 view of a cross-sectional structure of a valve core structure of a proportional reversing valve according to an embodiment of the present invention in a neutral state; FIG. 2 is an enlarged partial schematic view of N in FIG. 1; this embodiment is described with reference to fig. 3.
The valve core structure of the proportional reversing valve is slidably arranged in a shell 1, a high-pressure oil port P and at least one working oil port (A and B) are arranged in the shell 1, a slide hole 10 is arranged on the shell 1, and a valve core 2 is sleeved in the slide hole 10 and seals the slide hole 10 through a radial surface of the valve core 2; the valve core 2 slides so that a gap is provided between the radial end surface of the valve core 2 and the slide hole 10, and the gap is used for communicating the high-pressure oil port and the working oil port.
In general, two sliding holes are formed in the shell 1, and the valve core 2 is sleeved in the two sliding holes; the valve core 2 slides leftwards or rightwards, one side of the sliding hole is opened, so that the high-pressure oil port is communicated with one of the working oil ports, and reversing action is further executed.
In general, a high-pressure oil port is connected to a hydraulic pump in a hydraulic system for releasing high-pressure hydraulic oil through a high-pressure oil pipe.
The two working oil ports are respectively connected with two ends of the executing element so as to facilitate the execution of reversing action through the oil inlet and outlet pipe.
As shown in fig. 2 and 3, when the valve core 2 is located at the middle position, the surface of the valve core 2 contacting the sliding hole 10 is a shoulder sealing surface 20; a plurality of groups of reducing conical tables 21 are further arranged on the valve core 2, and each group of reducing conical tables 21 comprises at least two circular tables (L1 and L2) which are connected and have different slope slopes; a set of variable diameter conical tables 21 are respectively arranged on two sides of the shoulder sealing surface 20.
Generally, a total of four variable diameter frusta 21 are used to open P-a, P-B, a-T, B-T, respectively, not only for opening the working port, but also for opening the oil path between the working port and the oil return port T.
In the valve core structure of the proportional reversing valve of the embodiment, a plurality of lubricating oil grooves 25 are arranged on the shoulder sealing surface 20.
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, in the valve core structure of the proportional reversing valve of the present embodiment, the reducing round table 21 includes: a first round table L1 closely connected with the sealing surface of the shoulder and a second round table L2 closely connected with the first round table;
the slope of the second round table is larger than that of the first round table; the maximum diameter of the first round platform is smaller than the diameter of the shoulder sealing surface.
The first round table is cut off around the circular slope of the outer circle of the valve core, the structural style of the first round table enables the first round table to have a flow guiding effect on the flow of hydraulic oil, and when the valve core is in the reversing process, the flow guiding effect of the throttling groove can effectively improve the flow field of the hydraulic oil, reduce the flow resistance and be beneficial to the reversing stability of the valve core.
In the valve core structure of the embodiment, the slope of the second round table is larger than that of the first round table, so that the valve core structure is suitable for the working conditions of slow actuation and then fast actuation.
The valve core is manufactured by adopting a cutting process of an annular slope surrounding the outer circle of the valve core, and can be directly machined by adopting turning, so that the manufacturing process is simple; because the diameter-variable round table is cut off around the circular slope of the outer circle of the valve core, when the valve core is shifted rightwards, the flow passing area of the P through A and the B through T is calculated simply, and the flow passing through the valve core can be calculated rapidly, so that the proper throttling groove form can be designed rapidly according to different applied working conditions by changing the angle of the inclined plane of the round table, and the development aging is rapid.
In general, the valve element 2 has a laterally symmetrical structure and has two axial end surfaces corresponding to each other.
Further, the reducing round bench includes: a third round table; the third round table is adjacent to the second round table. The diameter-variable round table 21 can comprise more round tables with different slopes according to actual needs.
In the valve core structure of the proportional reversing valve of the embodiment, control oil paths (a and b) are respectively arranged on two sides of the shell, and two ends of the control oil paths are respectively contacted with two ends of the valve core 2.
Specifically, two control oil cavities are arranged in the shell 1, and the two control oil cavities are respectively connected with the control oil circuit; two ends of the valve core 2 are respectively positioned in the two control oil cavities; the control oil way drives the valve core 2 to slide through the control oil cavity.
And a pre-tightening spring 8 which is in contact with the valve core is also arranged in the control oil cavity.
When the control chambers a and B have no guide pressure, the valve core is arranged in the middle position under the action of the pre-tightening spring, and the oil ports P/A/B/T are not communicated; when the control cavity a has guide pressure, the guide pressure is against the spring, the valve core starts to move rightwards, so that the oil ports P and A are communicated, the oil ports B and T are communicated, and the moving distance is related to the guide pressure of the control cavity a; similarly, when the control cavity B has guide pressure, the oil ports P and B are communicated, and the oil ports A and T are communicated; therefore, the electro-hydraulic proportional reversing valve realizes the displacement continuous change of the valve core by continuously adjusting the pilot pressure of the control cavity.
The invention is manufactured by adopting the cutting process of the circular slope surrounding the outer circle of the valve core, and can be directly machined by turning, and the manufacturing process is simple; because the valve core adopts the design of the diameter-variable round table, when the valve core slides, the calculation of the overflow area is simple, and the flow passing through the valve core can be calculated rapidly.
In addition, the valve core structure of the proportional reversing valve has low manufacturing cost, compact structural design, ingenious structure, stable starting and stopping, convenient flow calculation and control and suitability for the implementation of the starting or reversing actions of various hydraulic systems.
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 (5)
1. The valve core structure of the proportional reversing valve is slidably arranged in a shell, a high-pressure oil port and at least one working oil port are arranged in the shell, and the proportional reversing valve is characterized in that a sliding hole is formed in the shell, and the valve core is sleeved in the sliding hole and seals the sliding hole through a radial surface of the valve core; the valve core slides so that a gap is formed between the radial end surface of the valve core and the sliding hole, and the gap is used for communicating the high-pressure oil port and the working oil port;
when the valve core is positioned in the middle position, the surface of the valve core, which is contacted with the sliding hole, is a shoulder sealing surface; the valve core is also provided with a plurality of groups of reducing conical tables, and each group of reducing conical tables comprises at least two circular tables which are connected and have different slope of the inclined plane; a group of diameter-variable conical tables are respectively arranged on two sides of the shoulder sealing surface;
the variable diameter frustum includes: the first round platform is tightly connected with the sealing surface of the shoulder, and the second round platform is tightly connected with the first round platform;
the slope of the second round table is larger than that of the first round table; the maximum diameter of the first round platform is smaller than the diameter of the shoulder sealing surface.
2. The valve core structure of a proportional reversing valve according to claim 1, wherein a plurality of lubrication grooves are provided on the shoulder seal surface.
3. The spool structure of a proportional reversing valve according to claim 1, wherein the reducing taper includes: a third round table; the third round table is adjacent to the second round table.
4. The spool structure of a proportional reversing valve according to any one of claims 1 to 2, wherein control oil passages are provided on both sides of the housing, respectively, and both ends of the two control oil passages are in contact with both ends of the spool, respectively.
5. The valve core structure of the proportional reversing valve according to claim 4, wherein two control oil chambers are arranged in the housing, and the two control oil chambers are respectively connected with the control oil path; two ends of the valve core are respectively positioned in the two control oil cavities; the control oil way drives the valve core to slide through the control oil cavity;
and a pre-tightening spring contacted with the valve core is further arranged in the control oil cavity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110123635.0A CN112797188B (en) | 2021-01-29 | 2021-01-29 | Valve core structure of proportional reversing valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110123635.0A CN112797188B (en) | 2021-01-29 | 2021-01-29 | Valve core structure of proportional reversing valve |
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| CN112797188A CN112797188A (en) | 2021-05-14 |
| CN112797188B true CN112797188B (en) | 2024-05-24 |
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| CN202110123635.0A Active CN112797188B (en) | 2021-01-29 | 2021-01-29 | Valve core structure of proportional reversing valve |
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Families Citing this family (3)
| 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 |
| CN113357214A (en) * | 2021-06-10 | 2021-09-07 | 涌镇液压机械（上海）有限公司 | Hydraulic 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 |
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| US3987814A (en) * | 1975-03-17 | 1976-10-26 | Caterpillar Tractor Co. | Flow responsive poppet relief valve |
| US4461321A (en) * | 1981-05-26 | 1984-07-24 | Bendiberica S.A. | Rotary hydraulic distributor for hydraulic power-drive systems |
| JPS63176743U (en) * | 1986-12-18 | 1988-11-16 | ||
| CN102116380A (en) * | 2011-02-28 | 2011-07-06 | 东莞市尚正机电科技有限公司 | High-speed heavy-load linear reciprocating buffer reversing valve |
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| WO2015024152A1 (en) * | 2013-08-19 | 2015-02-26 | 江苏恒立液压有限公司 | Energy-recycling hydraulic control main valve |
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2021
- 2021-01-29 CN CN202110123635.0A patent/CN112797188B/en active Active
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| US3987814A (en) * | 1975-03-17 | 1976-10-26 | Caterpillar Tractor Co. | Flow responsive poppet relief valve |
| US4461321A (en) * | 1981-05-26 | 1984-07-24 | Bendiberica S.A. | Rotary hydraulic distributor for hydraulic power-drive systems |
| JPS63176743U (en) * | 1986-12-18 | 1988-11-16 | ||
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| CN112797188A (en) | 2021-05-14 |
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