CN111810483A - Electro-hydraulic valve reversing anti-impact structure - Google Patents
Electro-hydraulic valve reversing anti-impact structure Download PDFInfo
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- CN111810483A CN111810483A CN202010769844.8A CN202010769844A CN111810483A CN 111810483 A CN111810483 A CN 111810483A CN 202010769844 A CN202010769844 A CN 202010769844A CN 111810483 A CN111810483 A CN 111810483A
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- 239000003921 oil Substances 0.000 claims abstract description 91
- 230000001105 regulatory effect Effects 0.000 claims abstract description 37
- 230000009467 reduction Effects 0.000 claims abstract description 23
- 230000009471 action Effects 0.000 claims abstract description 6
- 239000010720 hydraulic oil Substances 0.000 claims abstract description 4
- 238000004891 communication Methods 0.000 claims description 6
- 230000035939 shock Effects 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 5
- 230000000694 effects Effects 0.000 abstract description 3
- 230000009466 transformation Effects 0.000 abstract description 3
- 238000000034 method Methods 0.000 description 4
- 230000001276 controlling effect Effects 0.000 description 2
- 238000009434 installation 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
- 230000008569 process Effects 0.000 description 2
- 239000013589 supplement Substances 0.000 description 2
- 229910001208 Crucible steel Inorganic materials 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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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
-
- 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
- F15B13/025—Pressure reducing valves
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Safety Valves (AREA)
Abstract
The invention provides a reversing anti-impact structure of an electro-hydraulic valve, belonging to the field of manufacturing of electro-hydraulic valves; the invention comprises the following steps: a valve body; the valve body is provided with a flow guide hole and an oil outlet butted with the pilot valve, and a pressure reduction cavity is arranged in the valve body; a slidable valve core is arranged in the pressure reduction cavity, a pressure regulating screw rod is arranged at one end of the pressure reduction cavity, and a pre-tightened pressure spring is arranged between the pressure regulating screw rod and the valve core; two ends of the valve core are respectively used for radially plugging the flow guide hole and the oil outlet; the valve core compresses the pressure spring to slide under the action of hydraulic oil, so that the flow guide hole is connected with the oil outlet. According to the invention, the slidable valve core is arranged on the flow guide hole, so that high-pressure oil exceeding a threshold value can be ensured to enter the oil outlet, a pressure reduction effect is realized, the movement stability of the pilot valve can be effectively improved, the system safety is enhanced, and the difficulty in valve body transformation is reduced.
Description
Technical Field
The invention relates to an electro-hydraulic valve manufacturing technology, in particular to a reversing anti-impact structure of an electro-hydraulic valve, and belongs to the technical field of valve manufacturing.
Background
The electro-hydraulic directional valve is mainly used in a hydraulic system with the flow rate exceeding the normal working allowable range of the electromagnetic directional valve, and is used for controlling the action of an executing element or controlling the flow direction of oil.
In the prior art, the electro-hydraulic directional control valve is divided into an internal control type (control oil is taken from a P port of a main oil way) and an external control type (control oil is additionally provided with an independent oil source) according to the source of pressure oil of a pilot valve of the electro-hydraulic directional control valve, because the electro-hydraulic directional control valve is mostly used in a high-pressure and high-flow hydraulic control system, the directional impact is large when the internal control type is used, and the stability and the safety of the whole hydraulic system are influenced.
Therefore, an external control mode is often necessary, and an independent oil source with lower pressure is additionally arranged. However, this requires additional power, control and accessories, which results in a cost increase and a more complex system.
Disclosure of Invention
The invention provides a novel electro-hydraulic valve reversing impact-resistant structure, which can balance the oil pressure at the outlet of a main oil way by arranging a pressure reducing device at the outlet of the main oil way so as to solve the technical problem of overlarge reversing impact force of a pilot valve connected with the main oil way in the prior art.
The electro-hydraulic valve reversing impact-resistant structure of the embodiment of the invention comprises: a valve body; the valve body is provided with a flow guide hole and an oil outlet butted with the pilot valve, and a pressure reduction cavity is arranged in the valve body;
a slidable valve core is arranged in the pressure reduction cavity, a pressure regulating screw rod is arranged at one end of the pressure reduction cavity, and a pre-tightened pressure spring is arranged between the pressure regulating screw rod and the valve core;
two ends of the valve core are respectively used for radially plugging the flow guide hole and the oil outlet; the valve core compresses the pressure spring to slide under the action of hydraulic oil, so that the flow guide hole is connected with the oil outlet.
The electro-hydraulic valve reversing impact-resistant structure comprises a valve body, a valve rod, a pressure regulating screw and a pressure regulating screw rod, wherein the valve body is internally provided with the pressure regulating cavity;
the valve body is further provided with an oil return port and an oil return cavity, and the oil return port is connected with the oil return cavity through the pressure regulating cavity.
The electro-hydraulic valve reversing impact-resistant structure comprises a valve core, wherein the valve core is provided with a throttling hole, and the throttling hole is used for communicating the diversion hole with the oil outlet.
The electro-hydraulic valve reversing impact-resistant structure comprises a valve core, a valve rod, a connecting rod, a spring and a spring, wherein the valve core is provided with a plurality of cylinders;
the two cylinders are respectively positioned at two ends of the pressure reduction cavity and respectively correspond to the flow guide hole and the oil outlet so as to seal the flow guide hole and the oil outlet.
The electro-hydraulic valve reversing impact-resistant structure comprises a pressure regulating screw, a pressure regulating screw and a spring, wherein the pressure regulating screw is arranged at the end part of the pressure regulating screw; a nut is further installed on the outer side of the valve body; the screwing screw is arranged in the nut.
The electro-hydraulic valve reversing impact-resistant structure comprises a guide hole, wherein the front end of the guide hole is an inclined oil guide channel, and the section of the guide channel is gradually reduced along with the oil guide direction.
The electro-hydraulic valve reversing impact-resistant structure is characterized in that the pressure regulating cavity is connected with the pressure reducing cavity, and a communication hole is formed between the pressure regulating cavity and the pressure reducing cavity; the cylinder at one end of the valve core is positioned in the communicating hole; the valve body slides to open the communication hole.
The electro-hydraulic valve reversing impact-resistant structure comprises a valve body, wherein the valve body is provided with an oil return port and an oil outlet;
the top of the valve body is also provided with two guide holes; the upper part of the valve body is provided with a pilot electromagnetic valve; the pilot electromagnetic valve is connected with the valve body through the oil outlet, the oil return port and the guide hole.
According to the invention, the slidable valve core is arranged on the flow guide hole, so that high-pressure oil exceeding a threshold value can be ensured to enter the oil outlet, a pressure reduction effect is achieved, the motion stability of the pilot valve can be effectively improved, the system safety is enhanced, and the difficulty in valve body transformation is reduced.
Drawings
FIG. 1 is a side view of an electro-hydraulic valve reversal impact prevention structure of an embodiment of the present invention;
FIG. 2 is a schematic view of the pressure holding state at M in FIG. 1;
FIG. 3 is a schematic diagram of the pressure cutback condition at M in FIG. 1.
Detailed Description
The electro-hydraulic valve reversing impact-resistant structure can be made of the following materials, and is not limited to the following materials, for example: cast steel, a cylindrical spring, an electromagnetic valve, a ceramic valve core, a sealing ring, an oil guide channel, a valve interface and the like.
FIG. 1 is a side view of a reversing impact-resistant structure of an electro-hydraulic valve according to an embodiment of the present invention; and in conjunction with figures 2 and 3.
The electro-hydraulic valve reversing impact-resistant structure of the embodiment of the invention comprises: a valve body 1; the valve body 1 is provided with a flow guide hole 11 and an oil outlet 2 butted with a pilot valve, and a pressure reduction cavity is arranged in the valve body 1; the pressure reduction cavity is used for accommodating the pressure reduction device.
A slidable valve core 9 is arranged in the pressure reduction cavity, one end of the pressure reduction cavity is provided with a pressure regulating screw rod 4, and a pre-tightened pressure spring 41 is arranged between the pressure regulating screw rod 4 and the valve core 9; generally, the pressure spring 41 has a pressure adjusting screw 4 and a gasket 42 at its two ends, and the gasket 42 is used to contact with the valve element 9.
Two ends of the valve core 9 are respectively used for radially plugging the flow guide hole 11 and the oil outlet 2; the valve core 9 compresses the pressure spring 41 to slide under the action of hydraulic oil, so that the flow guide hole 11 is connected with the oil outlet 2.
In general, a pressure regulating cavity is further arranged in the valve body 1, and the pressure regulating screw rod 4 is arranged in the pressure regulating cavity; namely, the pressure regulating cavity can slide in order to regulate the pretightening force of the pressure spring, thereby adapting to the working conditions of different pressures.
The valve body 1 is further provided with an oil return port 3 and an oil return cavity 12, and the oil return port 3 is connected with the oil return cavity 12 through the pressure regulating cavity. The oil return chamber 12 is used for receiving pressure oil discharged by the pilot valve.
In the electrohydraulic valve reversing impact-proof structure of the present embodiment, the valve core 9 is provided with a throttle hole 90, and the throttle hole 90 is used for communicating the diversion hole and the oil outlet.
The invention comprises the following steps in the working process:
when the pressure-reducing valve works, the pressure-regulating screw rod is firstly regulated, so that the pressure threshold value of pressure reduction is regulated; the guide oil flowing to the pilot valve flows into the oil outlet 2 from the main pressure cavity of the oil guide hole 11, then flows into the oil outlet 2 rightwards through the central throttle hole of the valve core, when the pressure reaches a set value, the valve core 9 overcomes the preset elastic force of the pressure spring 41 to push the valve core 9 to move leftwards under the guide pressure pushing force, when a balance point is reached, the main pressure cavity of the oil guide hole 11 and the oil outlet 2 are divided into two chambers which are not communicated by the shoulder of the valve core 3, and at this time, no high-pressure oil flows into the oil outlet 2.
When the pressure thrust of the oil outlet 2 is lower than the set elastic force value of the overcome pressure spring 41, the pressure spring 41 can push the valve core 9 to move rightwards, and the oil guide hole 11 and the oil outlet 2 are instantly communicated for oil supplement (pressure supplement state) to ensure the pressure balance to be constant.
When the instantaneous pressure of the oil outlet subjected to interference is higher than the preset value, the valve core 9 is displaced leftwards to break a balance point, the oil outlet is communicated with the pressure regulating cavity at the moment, and the action of instantaneous overflow and pressure regulation is carried out, so that the constant pressure is ensured.
The pressure at the inlet (oil outlet 2) of the pilot valve is ensured to be adjustable and stable through the steps, and under the ordinary condition, no matter the internal control or external control type electro-hydraulic reversing valve, the lower pilot pressure oil can push the hydraulic main valve core to be smoothly switched. If the pressure is too high, larger hydraulic impact force can be caused, the service life of the whole hydraulic system control and the stability of matched equipment are influenced, and therefore the pressure of the guide oil is controlled to be of great importance for the stable switching of the electro-hydraulic valve.
In the electro-hydraulic valve reversing impact-resistant structure of the embodiment, two ends of the valve core 9 are both cylinders, and a connecting rod is arranged between the two cylinders; the two cylinders are respectively positioned at two ends of the pressure reduction cavity and respectively correspond to the flow guide hole 11 and the oil outlet 2 so as to seal the flow guide hole 11 and the oil outlet 2.
In the electro-hydraulic valve reversing impact-resistant structure of the embodiment, a screwing screw 40 is arranged at the end part of the pressure regulating screw rod 4; a nut 5 is also arranged on the outer side of the valve body 1; the tightening screw 40 is mounted in the nut 5.
In the use process, the nut 5 is opened, and the pressure threshold between the pressure regulating screw rod 4 and the pressure spring 41 can be adjusted by screwing the screw 40.
In the electro-hydraulic valve reversing impact-resistant structure of the embodiment, the front end of the flow guide hole 11 is an inclined oil guide channel 10, and the section of the flow guide channel 10 is gradually reduced along with the oil guide direction.
In the electro-hydraulic valve reversing impact-resistant structure of the embodiment, the pressure regulating cavity is connected with the pressure reducing cavity, and a communication hole is formed between the pressure regulating cavity and the pressure reducing cavity; the cylinder at one end of the valve core is positioned in the communicating hole; the valve body slides to open the communication hole.
In the reversing impact-proof structure of the electrohydraulic valve in the embodiment, the oil return port 3 and the oil outlet 2 are both positioned at the top of the valve body 1; to facilitate installation of the pilot valve.
The top of the valve body 1 is also provided with two guide holes (AB in the figure); the upper part of the valve body 1 is provided with a pilot electromagnetic valve; the pilot electromagnetic valve is connected with the valve body 1 through the oil outlet 2, the oil return port 3 and the guide hole.
According to the invention, the slidable valve core is arranged on the flow guide hole, so that high-pressure oil exceeding a threshold value can be ensured to enter the oil outlet, a pressure reduction effect is achieved, the motion stability of the pilot valve can be effectively improved, the system safety is enhanced, and the difficulty in valve body transformation is reduced.
The invention realizes the effective adjustable control of the pressure of the pilot valve on the premise of not needing an independent external control oil source, not increasing an additional valve group and basically not changing the appearance and the volume of the valve body. The impact force of pilot control pressure oil on two sides of the hydraulic main valve is effectively reduced, and the noise and the impact on the valve body during reversing switching are reduced. The service life of the hydraulic control reversing valve is prolonged, and the working stability and the safety of the hydraulic control reversing valve are ensured.
The electro-hydraulic valve reversing anti-impact structure provided by the embodiment of the invention has the advantages that:
1. when the electro-hydraulic valve reversing impact-resistant structure is used, a pilot electromagnetic valve and a hydraulic valve are combined, the structure is optimized mainly on the basis of the original structure of the hydraulic valve body, and parts and accessories of a constant pressure mechanism are added;
2. according to the electro-hydraulic valve reversing impact-resistant structure, the pressure reduction cavity hole is processed at the position below the middle of the original hydraulic main valve pilot valve surface P and the T functional port, the total height is unchanged, and the limit of a customer installation space is not influenced;
3. the electro-hydraulic valve reversing impact-resistant structure changes the channel of the oil guide cavity into the inclined hole channel in the valve body, provides enough space for processing the wall thickness for the pressure reduction cavity hole, changes the straight hole into the inclined hole, shortens the length of the flow channel and reduces the pressure drop loss.
In addition, the electro-hydraulic valve reversing impact-resistant structure is low in manufacturing cost, compact in structural design, stable in finished product quality, convenient to transform and low in manufacturing cost, and is suitable for main body structures of various electro-hydraulic valves.
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 (8)
1. An electro-hydraulic valve commutation protecting against shock structure for installing a pilot valve, the structure comprising: a valve body; the valve body is provided with a flow guide hole and an oil outlet butted with the pilot valve, and a pressure reduction cavity is arranged in the valve body;
a slidable valve core is arranged in the pressure reduction cavity, a pressure regulating screw rod is arranged at one end of the pressure reduction cavity, and a pre-tightened pressure spring is arranged between the pressure regulating screw rod and the valve core;
two ends of the valve core are respectively used for radially plugging the flow guide hole and the oil outlet; the valve core compresses the pressure spring to slide under the action of hydraulic oil, so that the flow guide hole is connected with the oil outlet.
2. The electro-hydraulic valve reversing impact-resistant structure according to claim 1, wherein a pressure regulating cavity is further arranged in the valve body, and the pressure regulating screw is arranged in the pressure regulating cavity;
the valve body is further provided with an oil return port and an oil return cavity, and the oil return port is connected with the oil return cavity through the pressure regulating cavity.
3. The electro-hydraulic valve reversing impact-resistant structure as claimed in claim 2, wherein a throttle hole is arranged on the valve core and used for communicating the diversion hole with the oil outlet.
4. The electro-hydraulic valve reversing impact-resistant structure according to claim 3, wherein both ends of the valve core are cylinders, and a connecting rod is arranged between the two cylinders;
the two cylinders are respectively positioned at two ends of the pressure reduction cavity and respectively correspond to the flow guide hole and the oil outlet so as to seal the flow guide hole and the oil outlet.
5. The electro-hydraulic valve reversing impact-resistant structure according to any one of claims 1 to 3, wherein a tightening screw is arranged at the end of the pressure regulating screw; a nut is further installed on the outer side of the valve body; the screwing screw is arranged in the nut.
6. The electro-hydraulic valve reversing impact-resistant structure according to any one of claims 1 to 3, wherein the front end of the flow guide hole is an inclined oil guide channel, and the cross section of the flow guide channel is gradually reduced along the oil guide direction.
7. The electro-hydraulic valve reversing impact-resistant structure according to claim 4, wherein the pressure regulating cavity is connected with the pressure reducing cavity, and a communication hole is formed between the pressure regulating cavity and the pressure reducing cavity; the cylinder at one end of the valve core is positioned in the communicating hole; the valve body slides to open the communication hole.
8. The electro-hydraulic valve reversing impact-resistant structure according to claim 2, wherein the oil return port and the oil outlet are both located at the top of the valve body;
the top of the valve body is also provided with two guide holes; the upper part of the valve body is provided with a pilot electromagnetic valve; the pilot electromagnetic valve is connected with the valve body through the oil outlet, the oil return port and the guide hole.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010769844.8A CN111810483A (en) | 2020-08-04 | 2020-08-04 | Electro-hydraulic valve reversing anti-impact structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010769844.8A CN111810483A (en) | 2020-08-04 | 2020-08-04 | Electro-hydraulic valve reversing anti-impact structure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111810483A true CN111810483A (en) | 2020-10-23 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010769844.8A Withdrawn CN111810483A (en) | 2020-08-04 | 2020-08-04 | Electro-hydraulic valve reversing anti-impact structure |
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| Country | Link |
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| CN (1) | CN111810483A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112797186A (en) * | 2021-02-02 | 2021-05-14 | 柯尔(苏州)医疗科技有限公司 | Special reversing combination valve for oxygenerator |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2445828A1 (en) * | 1973-09-26 | 1975-08-14 | Nippon Spindle Mfg Co Ltd | HYDRAULIC OSCILLATOR |
| EP0972948A2 (en) * | 1998-07-14 | 2000-01-19 | Smc Corporation | Pressure control valve for solenoid valve aggregate and solenoid valve assembly provided with the same |
| CN102072213A (en) * | 2010-10-22 | 2011-05-25 | 山东泰丰液压股份有限公司 | Pressure feedback secondary pilot control plugged-in type proportion relief valve system |
| CN103062148A (en) * | 2013-01-30 | 2013-04-24 | 浙江海克力液压有限公司 | Energy-saving type prior unloading valve |
| CN108087364A (en) * | 2017-12-19 | 2018-05-29 | 番禺珠江钢管（珠海）有限公司 | A kind of double pressure unloading valves |
| CN212272696U (en) * | 2020-08-04 | 2021-01-01 | 涌镇液压机械（上海）有限公司 | Electro-hydraulic valve reversing anti-impact structure |
-
2020
- 2020-08-04 CN CN202010769844.8A patent/CN111810483A/en not_active Withdrawn
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2445828A1 (en) * | 1973-09-26 | 1975-08-14 | Nippon Spindle Mfg Co Ltd | HYDRAULIC OSCILLATOR |
| EP0972948A2 (en) * | 1998-07-14 | 2000-01-19 | Smc Corporation | Pressure control valve for solenoid valve aggregate and solenoid valve assembly provided with the same |
| CN102072213A (en) * | 2010-10-22 | 2011-05-25 | 山东泰丰液压股份有限公司 | Pressure feedback secondary pilot control plugged-in type proportion relief valve system |
| CN103062148A (en) * | 2013-01-30 | 2013-04-24 | 浙江海克力液压有限公司 | Energy-saving type prior unloading valve |
| CN108087364A (en) * | 2017-12-19 | 2018-05-29 | 番禺珠江钢管（珠海）有限公司 | A kind of double pressure unloading valves |
| CN212272696U (en) * | 2020-08-04 | 2021-01-01 | 涌镇液压机械（上海）有限公司 | Electro-hydraulic valve reversing anti-impact structure |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112797186A (en) * | 2021-02-02 | 2021-05-14 | 柯尔(苏州)医疗科技有限公司 | Special reversing combination valve for oxygenerator |
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| WW01 | Invention patent application withdrawn after publication |
Application publication date: 20201023 |
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| WW01 | Invention patent application withdrawn after publication |