CN112797188A - Valve core structure of proportional reversing valve - Google Patents
Valve core structure of proportional reversing valve Download PDFInfo
- Publication number
- CN112797188A CN112797188A CN202110123635.0A CN202110123635A CN112797188A CN 112797188 A CN112797188 A CN 112797188A CN 202110123635 A CN202110123635 A CN 202110123635A CN 112797188 A CN112797188 A CN 112797188A
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- valve core
- valve
- reducing
- circular truncated
- truncated cone
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- 238000007789 sealing Methods 0.000 claims abstract description 19
- 239000003921 oil Substances 0.000 abstract description 48
- 238000004519 manufacturing process Methods 0.000 abstract description 8
- 238000005520 cutting process Methods 0.000 abstract description 4
- 238000013461 design Methods 0.000 abstract description 4
- 239000010720 hydraulic oil Substances 0.000 abstract description 4
- 230000009471 action Effects 0.000 description 4
- 230000007935 neutral effect Effects 0.000 description 4
- 238000004364 calculation method Methods 0.000 description 3
- 239000010687 lubricating oil Substances 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 230000008859 change Effects 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
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 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
- 238000010276 construction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 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
Images
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
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- 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, belonging to the field of reversing valve manufacturing; the hydraulic oil cylinder is slidably arranged in a shell, a high-pressure oil port and at least one working oil port are arranged in the shell, a slide hole is formed in the shell, and the valve core is sleeved in the slide hole and seals the slide hole through the radial surface of the valve core; the valve core slides to enable a gap to be formed between the radial end face 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 at the middle position, the surface of the valve core, which is contacted with the slide hole, is a shoulder sealing surface; the valve core is also provided with a plurality of groups of reducing frustum, and each group of reducing frustum comprises at least two connected circular truncated cones with different slopes; and a group of reducing cones are respectively arranged on two sides of the shoulder sealing surface. The valve core is manufactured by adopting a circular slope cutting process around the outside of the valve core, can be directly machined by turning, and is simple in manufacturing process; because the valve core adopts the design of the reducing circular truncated cone, when the valve core slides, the flow area of the valve core is simple to calculate, and the flow passing through the valve core can be quickly calculated.
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 used as a hydraulic element for controlling the on-off and reversing of an oil path, and is very commonly applied. The common reversing valve is of a slide valve type structure, a valve core of the reversing valve slides in a valve body, and the reversing is realized by switching the valve core, so that different oil ports are communicated or closed.
The opening of the valve core of the proportional reversing valve can be changed along with the change of the control instruction, so that the movement speed of the execution element can be continuously adjusted by adjusting the overflow of the proportional reversing valve, the control is simple and convenient, and the control precision is high; in order to control the flow adjustment, a valve core of the proportional reversing valve is provided with a plurality of throttling grooves, and the flow passing rate 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 forms such as triangle, U-shaped, rectangle and the like according to different application working conditions, and the cost of the proportional reversing valve is higher due to high processing difficulty and complex processing technology of the throttling grooves; when the throttling groove is designed, the shape of the throttling groove is special, the size of the flow area of the valve core under a certain opening degree is calculated more complicated, the difference between theoretical calculation and actual test is larger, and the development timeliness of the proportional reversing valve is slower.
Therefore, the valve core in the prior art is inconvenient for calculating the flow rate, and the error between the calculation error and the actual application is large.
Disclosure of Invention
The invention provides a novel valve core structure of a proportional reversing valve, which solves the technical problem that the flow is difficult to accurately calculate in the opening state of the valve core in the prior art by designing a reducing circular truncated cone on the edge of the sealing end surface of the valve core.
The valve core structure of the proportional reversing valve provided by the embodiment of the invention is slidably arranged in a shell, a high-pressure oil port and at least one working oil port are arranged in the shell, a slide hole is arranged on the shell, and the valve core is sleeved in the slide hole and seals the slide hole through the radial surface of the valve core; the valve core slides to enable a gap to be formed between the radial end face 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 at the middle position, the surface of the valve core, which is contacted with the slide hole, is a shoulder sealing surface; the valve core is also provided with a plurality of groups of reducing frustum, and each group of reducing frustum comprises at least two connected circular truncated cones with different slopes; and a group of reducing cones are respectively arranged on two sides of the shoulder sealing surface.
The valve core structure of the proportional directional valve is characterized in that the shoulder sealing surface is provided with a plurality of lubricating oil grooves.
The valve core structure of the proportional directional valve, wherein the reducing circular truncated cone comprises: the first circular truncated cone is tightly connected with the shoulder sealing surface, and the second circular truncated cone is tightly connected with the first circular truncated cone;
the slope of the inclined plane of the second round table is greater than that of the inclined plane of the first round table; the maximum diameter of the first truncated cone is smaller than the diameter of the shoulder sealing surface.
The valve core structure of the proportional directional valve is a bilaterally symmetrical structure and is provided with two axial end faces which correspond to each other.
The valve core structure of the proportional directional valve, wherein the reducing circular truncated cone comprises: a third round table; the third round table is adjacent to the second round table.
The valve core structure of the proportional directional valve is characterized in that two sides of the casing are respectively provided with a control oil path, and two ends of the two control oil paths are respectively contacted with two ends of the valve core.
The valve core structure of the proportional reversing valve comprises a casing, a control oil passage and a control oil passage, wherein the casing is internally provided with two control oil chambers which are respectively connected with the control oil passage; 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 which is contacted with the valve core is also arranged in the control oil cavity.
The valve core is manufactured by adopting a circular slope cutting process around the outside of the valve core, can be directly machined by turning, and is simple in manufacturing process; because the valve core adopts the design of the reducing circular truncated cone, when the valve core slides, the flow area of the valve core is simple to calculate, and the flow passing through the valve core can be quickly calculated.
Drawings
FIG. 1 is a schematic cross-sectional view of a valve core structure of a proportional directional valve according to an embodiment of the present invention in a neutral position;
FIG. 2 is an enlarged view of a portion N of FIG. 1;
fig. 3 is another schematic structural diagram of fig. 2.
Detailed Description
The valve core structure of the proportional directional valve of the present invention can be made of the following materials, and is not limited to the following materials, for example: common components such as a valve core, a hydraulic matching system, an electric control device and the like.
FIG. 1 is a schematic cross-sectional view of a valve core structure of a proportional directional valve according to an embodiment of the present invention in a neutral position; FIG. 2 is an enlarged view of a portion N of FIG. 1; this embodiment is described with reference to fig. 3.
The valve core structure of the proportional reversing valve provided by the embodiment of the invention 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 the radial surface of the valve core 2; the valve core 2 slides, so that a gap is formed between the radial end face 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.
Generally, the housing 1 is provided with two slide holes, and the valve core 2 is sleeved in the two slide holes; the valve core 2 slides leftwards or rightwards, and the sliding hole on one side is opened, so that the high-pressure oil port is communicated with one of the working oil ports, and the reversing action is executed.
Generally, the high-pressure oil port is connected to a hydraulic pump in the hydraulic system, and is used 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 actuating element so as to execute reversing action through the oil inlet and outlet pipes.
As shown in fig. 2 and 3, when the valve core 2 is located at the neutral position, the surface of the valve core 2 contacting the slide 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 connected round tables (L1 and L2) with different slope slopes; and a group of reducing cones 21 are respectively arranged on two sides of the shoulder sealing surface 20.
Generally speaking, four groups of variable diameter frustum 21 are used for opening P-A, P-B, A-T and B-T respectively, and are used for opening not only the working oil port, but also the oil path between the working oil port and the oil return port T.
In the valve core structure of the proportional directional valve of the present embodiment, a plurality of lubricating oil grooves 25 are formed on each of the shoulder sealing surfaces 20.
Most of the lubricating oil groove 25 corresponds to the sealing surface of the sliding hole, so that the valve core is subjected to the suspension supporting action of oil pressure, the friction force of the movement of the valve core is reduced, and the hydraulic clamping force of the valve core is reduced, so that the valve can be normally reversed when the reversing valve is in a neutral position for a long time and needs to be reversed.
As shown in fig. 2, in the valve core structure of the proportional directional valve of the present embodiment, the reducing circular truncated cone 21 includes: a first truncated cone L1 in intimate contact with said shoulder sealing surface, and a second truncated cone L2 in intimate contact with said first truncated cone;
the slope of the inclined plane of the second round table is greater than that of the inclined plane of the first round table; the maximum diameter of the first truncated cone is smaller than the diameter of the shoulder sealing surface.
Because the first round table is cut off around the outer annular slope of the valve core, the structure 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 inclined surface of the second circular truncated cone is greater than that of the inclined surface of the first circular truncated cone, so that the valve core structure is suitable for the working condition of firstly slowly actuating and then quickly actuating.
The valve core is manufactured by adopting a circular slope cutting process around the outer circle of the valve core, so that the valve core can be directly machined by turning, and the manufacturing process is simple; because the reducing circular truncated cone is cut off around the outer circular slope of the valve core, when the valve core is displaced and changed rightwards, the through-flow area of the valve core P through A and the through-flow area of the valve core B through T are simple to calculate, and the flow passing through the valve core can be quickly calculated, so that the angle of the circular truncated cone inclined plane can be changed according to different applied working conditions, the width is quickly designed into a proper throttling groove form, and the development and the aging are quick.
Generally, the valve element 2 has a left-right symmetrical structure and has two axial end faces corresponding to each other.
Further, the reducing round platform includes: a third round table; the third round table is adjacent to the second round table. The reducing circular truncated cone 21 can comprise more circular truncated cones with different slopes according to actual needs.
In the valve core structure of the proportional directional valve of the embodiment, two sides of the casing are respectively provided with control oil paths (a and b), and two ends of the two 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 are respectively connected with the control oil way; two ends of the valve core 2 are respectively positioned in the two control oil cavities; the control oil path drives the valve core 2 to slide through the control oil cavity.
And a pre-tightening spring 8 which is contacted with the valve core is also arranged in the control oil cavity.
When the control cavities a and B have no guide pressure, the valve core is placed in a middle position under the action of a 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 counterbalanced with 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 size of 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 directional valve realizes the continuous change of the displacement of the valve core by continuously adjusting the magnitude of the guide pressure of the control cavity.
The valve core is manufactured by adopting a circular slope cutting process around the outside of the valve core, can be directly machined by turning, and is simple in manufacturing process; because the valve core adopts the design of the reducing circular truncated cone, when the valve core slides, the flow area of the valve core is simple to calculate, and the flow passing through the valve core can be quickly calculated.
In addition, the valve core structure of the proportional reversing valve has the advantages of 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 above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments. Through the above description of the embodiments, those skilled in the art will clearly understand that the above embodiment method can be implemented by some modifications plus the necessary general technical overlap; of course, the method can also be realized by simplifying some important technical features in the upper level. Based on such understanding, the technical solution of the present invention essentially or contributing to the prior art is: overall function and construction, and to cooperate with the structure described in the various embodiments of the present invention.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (7)
1. A valve core structure of a proportional reversing valve is slidably arranged in a shell, and a high-pressure oil port and at least one working oil port are arranged in the shell; the valve core slides to enable a gap to be formed between the radial end face 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 at the middle position, the surface of the valve core, which is contacted with the slide hole, is a shoulder sealing surface; the valve core is also provided with a plurality of groups of reducing frustum, and each group of reducing frustum comprises at least two connected circular truncated cones with different slopes; and a group of reducing cones are respectively arranged on two sides of the shoulder sealing surface.
2. The valve core structure of the proportional directional valve according to claim 1, wherein a plurality of oil grooves are provided on each of the shoulder sealing surfaces.
3. The valve core structure of the proportional directional valve according to claim 1, wherein the reducing circular truncated cone comprises: the first circular truncated cone is tightly connected with the shoulder sealing surface, and the second circular truncated cone is tightly connected with the first circular truncated cone;
the slope of the inclined plane of the second round table is greater than that of the inclined plane of the first round table; the maximum diameter of the first truncated cone is smaller than the diameter of the shoulder sealing surface.
4. The spool structure of the proportional directional valve according to claim 1, wherein the spool has a left-right symmetrical structure and has two axial end faces corresponding to each other.
5. The valve core structure of the proportional directional valve according to claim 3, wherein the reducing circular truncated cone comprises: a third round table; the third round table is adjacent to the second round table.
6. The spool structure of the proportional directional valve according to any of claims 1 to 3, 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.
7. The valve core structure of the proportional reversing valve according to claim 6, wherein two control oil chambers are provided in the housing, and the two control oil chambers are respectively connected to the control oil passages; 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 which is contacted with the valve core is also 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 |
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| 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 true CN112797188A (en) | 2021-05-14 |
| CN112797188B 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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Cited By (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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2021
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| JPS63176743U (en) * | 1986-12-18 | 1988-11-16 | ||
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Cited By (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 |
Also Published As
| Publication number | Publication date |
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| CN112797188B (en) | 2024-05-24 |
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