CN112412916A - Hydraulic combination valve based on sequential decompression and overflow functions - Google Patents
Hydraulic combination valve based on sequential decompression and overflow functions Download PDFInfo
- Publication number
- CN112412916A CN112412916A CN202011609236.7A CN202011609236A CN112412916A CN 112412916 A CN112412916 A CN 112412916A CN 202011609236 A CN202011609236 A CN 202011609236A CN 112412916 A CN112412916 A CN 112412916A
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- valve
- port
- valve core
- oil
- pressure
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Classifications
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- 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
- F15B13/024—Pressure relief valves
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- 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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- 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
- F15B2013/002—Modular valves, i.e. consisting of an assembly of interchangeable components
- F15B2013/004—Cartridge valves
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- 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
- F15B2013/002—Modular valves, i.e. consisting of an assembly of interchangeable components
- F15B2013/006—Modular components with multiple uses, e.g. kits for either normally-open or normally-closed valves, interchangeable or reprogrammable manifolds
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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 discloses a hydraulic combination valve based on a sequential pressure reduction and overflow function, which comprises a valve sleeve, a valve core and a pressure spring, wherein the valve sleeve is formed with a valve cavity; the valve core is provided with a central oil duct from the bottom surface; an annular control groove is processed on the circumferential surface of the valve core, a pressure oil port for radially communicating the port P with the central oil duct is arranged in the annular control groove, and a connecting oil hole for communicating the central oil duct with the port B after the valve core moves upwards is further processed on the valve core; the control edge of the annular control groove and the opening edge of the port P form a throttling area for realizing the pressure reduction function of the valve when the valve core moves upwards, and an upper shoulder with longitudinal sections at two sides and a lower shoulder positioned below the upper shoulder are formed on the valve core; when the valve core is in an original state, the port B is communicated with the port T, and when the valve core moves upwards, the longitudinal section is matched with the inner shoulder of the valve sleeve to form a damping channel which can enable part of oil in the port B to flow back to the port T and is used for realizing the overflow function of the valve.
Description
Technical Field
The invention relates to the technical field of hydraulic control, in particular to a hydraulic valve with a composite function, and specifically relates to a hydraulic composite valve based on a sequential pressure reduction and overflow function.
Background
The hydraulic valve is widely used in hydraulic equipment and hydraulic elements and is divided into a plate type, a tubular type and a plug-in type. Cartridge hydraulic valves are used in a large number of compact hydraulic components due to the spatial constraints of the equipment and components. Especially in the hydraulic rotary motor, the hydraulic rotary motor has small volume and convenient installation, and can greatly save space and be widely used. However, most rotary motors have a separate cartridge valve for each function, which requires a high space requirement for the cartridge body. Often, many cartridge valves of dense hemp are arranged on the valve body, which brings troubles to use, installation and subsequent maintenance.
Disclosure of Invention
The invention aims to solve the technical problem of the prior art and provides a hydraulic combination valve based on a sequential decompression overflow function, which has small volume, few parts and compact structure and can realize sequential decompression overflow.
The technical scheme adopted by the invention for solving the technical problems is as follows:
a hydraulic combination valve based on a sequential pressure reduction and overflow function comprises a valve sleeve and a valve core, wherein the valve sleeve is formed with a valve cavity, the valve core is arranged in the valve cavity of the valve sleeve in a sliding mode, a pressure spring used for applying pre-tightening pressure to the valve core is installed in the valve cavity, and a high-pressure oil P port, a secondary pressure B port and an oil return T port are formed on the circumferential surface of the valve sleeve from bottom to top; the valve core is provided with a central oil duct which can enable hydraulic oil to enter from the bottom surface along the axis to push the valve core to overcome the resistance of the pressure spring to move upwards; a concave annular control groove is circumferentially processed on the peripheral surface of the valve core at the position corresponding to the port P, a pressure oil port for radially communicating the port P with the central oil duct is arranged in the annular control groove, and a connecting oil hole for communicating the central oil duct with the port B after the valve core moves upwards is further processed on the valve core; the control edge of the annular control groove and the opening edge of the P port form a throttling area for realizing the pressure reduction function of the valve when the valve core moves upwards, and an upper shoulder with longitudinal sections on two sides and a lower shoulder which is positioned below the upper shoulder and is used for blocking the communication between the oil connecting hole and the B port when the valve core is in an original state are formed on the valve core; when the valve core is in an original state, the port B is communicated with the port T, and when the valve core moves upwards, the longitudinal section is matched with the inner shoulder of the valve sleeve to form a damping channel which can enable part of oil in the port B to flow back to the port T and is used for realizing the overflow function of the valve.
In order to optimize the technical scheme, the specific measures adopted further comprise:
the bottom of the valve cavity is a closed end, and a cavity opening of the valve cavity is spirally provided with a pressure regulating plug; the valve core is formed into a spring guide rod section for preventing the radial deviation of the pressure spring, the pressure spring is sleeved on the spring guide rod section of the valve core, the lower end of the pressure spring is connected with the valve core in a propping mode, and the upper end of the pressure spring is connected with the pressure regulating plug in a propping mode.
The valve sleeve is provided with an external thread for the plug-in type screw assembly with the valve hole of the mounting component, and the upper part of the valve sleeve is provided with a positioning boss which is in butt joint and positioning fit with the mounting component.
The sealing ring for preventing the oil leakage of the valve hole is sleeved below the positioning boss of the valve sleeve.
The width of the small-diameter annular control groove of the pressure oil port is characterized in that an annular connecting groove is formed in the circumferential surface of the valve core, a connecting oil hole is formed in the annular connecting groove, and the diameter of the connecting oil hole is smaller than the width of the annular connecting groove.
An annular damping groove capable of guiding oil at the port B into the damping channel is formed between the lower shoulder and the upper shoulder.
The bottom surface of the valve core is radially provided with a bottom groove channel which can enable the hydraulic oil in the central oil duct to easily enter the bottom surface of the valve core.
The cross section of the positioning boss is hexagonal for being screwed by a wrench conveniently.
Compared with the prior art, the hydraulic compound valve only comprises four components, namely a valve sleeve, a valve core, a pressure spring and a pressure regulating plug. The valve core is provided with an annular control groove, the control edge of the annular control groove can be matched with the opening edge of the port P to realize the pressure reduction function of the valve, longitudinal sections are turned on two sides of the upper shoulder of the valve core, and the longitudinal sections can be matched with the inner shoulder of the valve sleeve to form a damping channel which can enable part of oil of the port B to flow back to the port T to realize the overflow function of the valve.
The invention adopts plug-in connection, has compact structure and less required parts, and can realize the function of sequential decompression and overflow.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a cross-sectional structural view of the valve cartridge of FIG. 1;
FIG. 3 is a schematic perspective view of the valve cartridge;
FIG. 4 is a schematic view of the restriction area of the valve opening of the present invention expanded;
FIG. 5 is a schematic perspective view of the present invention;
FIG. 6 is a schematic view of the assembled structure of the present invention and the mounting member;
fig. 7 is a hydraulic schematic of the present invention.
Detailed Description
Embodiments of the present invention are described in further detail below with reference to the accompanying drawings.
Fig. 1 to 7 are schematic diagrams illustrating the structure and principle of the present invention.
Wherein the reference numerals are: the hydraulic control valve comprises an acting surface S, a sealing ring M, a damping channel Z, an annular damping groove Z1, a throttling area Ax, a control edge Lx, a port edge Lt, a valve sleeve 1, a valve cavity 1a, an inner shoulder 1b, an external thread 1c, a positioning boss 11, a valve core 2, a central oil passage 2a, an annular control groove 2b, a pressure oil port 2c, a connecting oil hole 2d, an annular connecting groove 2e, a bottom groove channel 2f, a spring guide rod section 21, an upper shoulder 22, a longitudinal tangent plane 22a, a lower shoulder 23, a pressure spring 3, a pressure regulating plug 4 and a mounting part 5.
As shown in the figure, the invention discloses a hydraulic compound valve based on a sequential pressure reduction and overflow function, which adopts a plug-in type structure and can be directly and spirally plugged into a valve hole processed by a mounting component 5, so that the hydraulic compound valve is convenient to mount, and is simple and rapid. The mounting part 5 here may be a housing or other housing of the hydraulic motor. The valve is composed of four parts, and comprises a valve sleeve 1, a valve core 2, a pressure spring 3 and a pressure regulating plug 4. The valve housing 1 is axially formed with a valve cavity 1a with a closed bottom, and the valve core 2 is slidably disposed in the valve cavity 1a of the valve housing 1. The pressure spring 3 is also arranged in the valve cavity 1a, and the pressure spring 3 is used for applying downward pre-tightening pressure to the valve core 2, so that the valve core 2 is in an original state when the pressure of hydraulic oil is smaller than the spring force of the pressure spring 3, namely the state when the bottom surface of the valve core 2 is abutted against the bottom wall of the valve cavity 1 a. The pressure regulating plug 4 is spirally arranged at the orifice of the valve cavity 1a and is used for regulating the pre-tightening pressure of the pressure spring 3, thereby changing the pressure of the action of the valve core 2. The pressure spring 3 is pressed between the pressure regulating plug 4 and the valve core 2, in order to prevent the pressure spring 3 from radially deviating and influencing the stability of the valve opening, the valve core 2 is provided with a spring guide rod section 21, and the spring guide rod section 21 can provide a guide effect for the pressure spring 3. The pressure spring 3 is sleeved on the spring guide rod section 21 of the valve core 2, the lower end of the pressure spring 3 is connected with the valve core 2 in a propping mode, and the upper end of the pressure spring 3 is connected with the pressure regulating plug 4 in a propping mode.
As can be seen from fig. 1, a high-pressure oil port P, a secondary pressure port B and an oil return port T are formed on the circumferential surface of the valve sleeve 1 of the present invention; and the port P, the port B and the port T are arranged on the valve sleeve 1 at intervals from bottom to top. The port P is a high-pressure hydraulic oil port of the hydraulic system, the port B is a secondary pressure oil port of the hydraulic system, and the port T is an oil return port of the hydraulic system, and the oil return port is connected with an oil tank. As can be seen from fig. 2, a central oil passage 2a is formed along the axis of the valve core 2 from the bottom surface, a concave annular control groove 2b is formed on the circumferential surface of the valve core 2 at the position corresponding to the P port in the circumferential direction, and a pressure oil port 2c for radially communicating the P port with the central oil passage 2a is formed in the annular control groove 2b, so that high-pressure oil at the P port can enter the central oil passage 2a through the annular control groove 2b and the pressure oil port 2c, and the high-pressure oil acts on the acting surface S of the valve core to push the valve core 2 to move upward against the resistance of the pressure spring 3. The valve core 2 is further provided with a connecting oil hole 2d which is used for communicating the central oil passage 2a with the port B after the valve core 2 moves upwards, so that high-pressure hydraulic oil entering the central oil passage 2a can flow to the port B of the secondary pressure through the connecting oil hole 2 d. The edge of the annular control groove 2b can be used as a control edge LX to be matched with the opening edge LT of the opening P, and a throttling area AX is formed when the valve core 2 moves upwards, so that the pressure reducing function of the valve is realized. The valve element 2 of the present invention is also formed with an upper land 22 and a lower land 23 having the same diameter. The lower land 23 is located below the upper land 22, and the position of the lower land 23 on the valve spool is capable of blocking the communication of the connecting oil hole 2d with the B port just when the valve spool 2 is in the original state (see the state in fig. 1). When the valve core 2 is in the original state, the port B is communicated with the port T. The upper shoulder 22 of the invention is longitudinally cut at a distance of 180 degrees to form a longitudinal section 22a, the longitudinal section 22a is matched with the inner shoulder 1B of the valve sleeve 1 when the valve core moves upwards to form a damping channel Z, and the damping channel Z can make part of oil flow of the port B return to the port T so as to realize the overflow function of the valve.
In the embodiment, the valve sleeve 1 of the present invention is formed with an external thread 1c for plug-in screw assembly with the valve hole of the mounting member 5, and the upper portion of the valve sleeve 1 is formed with a positioning boss 11 for abutting against and positioning-fitting with the mounting member 5. The positioning boss 11 is designed into a regular hexagon so as to facilitate screwing and fixing the screw fastening device of the invention on the mounting component 5 by a wrench.
As shown in fig. 6, in order to prevent oil leakage from the screw hole, the present invention designs a seal ring groove below the positioning boss 11, and a seal ring M for preventing oil leakage from the valve hole is installed in the seal ring groove.
In the embodiment of the invention, the diameter of the pressure oil port 2c is smaller than the width of the annular control groove 2b, an annular connecting groove 2e is further formed on the circumferential surface of the valve core 2, the connecting oil hole 2d is formed in the annular connecting groove 2e, and the diameter of the connecting oil hole 2d is smaller than the width of the annular connecting groove 2 e.
In the embodiment shown in fig. 3, the present invention further forms an annular damping groove Z1 between the lower shoulder 23 and the upper shoulder 22 for guiding the oil from port B into the damping passage Z.
In the embodiment, the bottom surface of the valve core 2 of the present invention is radially provided with a bottom groove 2f which enables the hydraulic oil in the central oil passage 2a to easily enter the bottom surface of the valve core 2.
The working principle of the invention is as follows: the hydraulic oil enters the central oil passage 2a from the port P, and because the port P and the secondary pressure port B are separated by the lower shoulder 23 under the action of the pressure spring 3, the secondary pressure port B is communicated with the oil return port T at the moment, and the secondary pressure Br is zero. When the pressure of the hydraulic oil on the valve core 2 overcomes the pre-tightening pressure of the pressure spring 3 along with the increase of the pressure of the hydraulic oil, the valve core 2 starts to move upwards to open the lower shoulder 23, the hydraulic oil flows to the secondary pressure port B through the connecting oil hole 2d, and the hydraulic oil flows. The orifice side LT of the hydraulic oil P port of the valve sleeve 1 and the control side LX of the valve core 2 form a throttling area AX, so that the valve is decompressed. The decompressed pressure Br passes through the action surface S of the valve core 2 to enable the valve core 2 to move upwards to be balanced with the pressure spring 3. In addition, the oil at the opening B is shunted by a part of the oil return tank through the damping channel Z to form the overflow valve function of secondary pressure Br, so that the secondary pressure is not increased.
While the preferred embodiments of the present invention have been illustrated, various changes and modifications may be made by one skilled in the art without departing from the scope of the invention.
Claims (8)
1. The hydraulic combination valve based on the sequential pressure reduction and overflow function comprises a valve sleeve (1) formed with a valve cavity (1a) and a valve core (2) arranged in the valve cavity (1a) of the valve sleeve (1) in a sliding mode, and is characterized in that: a pressure spring (3) for applying pre-tightening pressure to the valve core (2) downwards is arranged in the valve cavity (1a), and a high-pressure oil P port, a secondary pressure B port and an oil return T port are formed on the circumferential surface of the valve sleeve (1) from bottom to top; the valve core (2) is provided with a central oil duct (2a) which can enable hydraulic oil to enter from the bottom surface along the axis to push the valve core (2) to move upwards against the resistance of the pressure spring (3); a concave annular control groove (2B) is circumferentially processed on the peripheral surface of the valve core (2) at a position corresponding to the P port, a pressure oil port (2c) for radially communicating the P port with the central oil duct (2a) is arranged in the annular control groove (2B), and a connecting oil hole (2d) for communicating the central oil duct (2a) with the B port after the valve core (2) moves upwards is further processed on the valve core (2); a throttle Area (AX) for realizing the valve decompression function is formed by a control edge (LX) of the annular control groove (2B) and a port edge (LT) of the port P when the valve core (2) moves upwards, an upper shoulder (22) with longitudinal tangent planes (22a) at two sides and a lower shoulder (23) which is positioned below the upper shoulder (22) and is used for blocking the communication between the oil connecting hole (2d) and the port B when the valve core (2) is in an original state are formed on the valve core (2); when the valve core is in an original state, the port B is communicated with the port T, and the longitudinal section (22a) is matched with the inner shoulder (1B) of the valve sleeve (1) when the valve core moves upwards to form a damping channel (Z) which can enable part of oil in the port B to return to the port T for realizing the overflow function of the valve.
2. The hydraulic compound valve based on the sequential decompression overflow function as claimed in claim 1, wherein: the bottom of the valve cavity (1a) is a closed end, and a pressure regulating plug (4) is spirally arranged at the cavity opening of the valve cavity (1 a); the valve core (2) is formed into a spring guide rod section (21) for preventing the radial deviation of the pressure spring (3), the pressure spring (3) is sleeved on the spring guide rod section (21) of the valve core (2), the lower end of the pressure spring (3) is connected with the valve core (2) in a jacking mode, and the upper end of the pressure spring (3) is connected with the pressure regulating plug (4) in a jacking mode.
3. The hydraulic compound valve based on the sequential decompression overflow function as claimed in claim 2, wherein: the valve sleeve (1) is formed with an external thread (1c) which is used for being spirally assembled with a valve hole plug-in type of the mounting component (5), and the upper part of the valve sleeve (1) is formed with a positioning boss (11) which is connected with the mounting component (5) in a jacking and positioning matching mode.
4. The hydraulic compound valve based on the sequential decompression overflow function as claimed in claim 3, wherein: and a sealing ring (M) for preventing the oil leakage of the valve hole is sleeved below the positioning boss (11) of the valve sleeve (1).
5. The hydraulic compound valve based on the sequential decompression overflow function as claimed in claim 4, wherein: the width of the small annular control groove (2b) of the diameter of the pressure oil port (2c), an annular connecting groove (2e) is formed on the circumferential surface of the valve core (2), the connecting oil hole (2d) is formed in the annular connecting groove (2e), and the diameter of the connecting oil hole (2d) is smaller than the width of the annular connecting groove (2 e).
6. The hydraulic compound valve based on the sequential decompression overflow function as claimed in claim 5, wherein: an annular damping groove (Z1) which can guide the oil of the port B into the damping channel (Z) is formed between the lower shoulder (23) and the upper shoulder (22).
7. The hydraulic compound valve based on the sequential decompression overflow function as claimed in claim 6, wherein: and a bottom groove channel (2f) which can enable hydraulic oil in the central oil duct (2a) to easily enter the bottom surface of the valve core (2) is radially processed on the bottom surface of the valve core (2).
8. The hydraulic compound valve based on the sequential decompression overflow function as claimed in claim 7, wherein: the cross section of the positioning boss (11) is hexagonal which is convenient to screw by a wrench.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011609236.7A CN112412916A (en) | 2020-12-30 | 2020-12-30 | Hydraulic combination valve based on sequential decompression and overflow functions |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011609236.7A CN112412916A (en) | 2020-12-30 | 2020-12-30 | Hydraulic combination valve based on sequential decompression and overflow functions |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112412916A true CN112412916A (en) | 2021-02-26 |
Family
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011609236.7A Pending CN112412916A (en) | 2020-12-30 | 2020-12-30 | Hydraulic combination valve based on sequential decompression and overflow functions |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112412916A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113428120A (en) * | 2021-07-16 | 2021-09-24 | 力源液压（苏州）有限公司 | Pressure reducing valve integrated with time delay function |
| CN113685388A (en) * | 2021-07-19 | 2021-11-23 | 北京天地玛珂电液控制系统有限公司 | Water-based proportional pressure-reducing overflow valve |
-
2020
- 2020-12-30 CN CN202011609236.7A patent/CN112412916A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113428120A (en) * | 2021-07-16 | 2021-09-24 | 力源液压（苏州）有限公司 | Pressure reducing valve integrated with time delay function |
| CN113685388A (en) * | 2021-07-19 | 2021-11-23 | 北京天地玛珂电液控制系统有限公司 | Water-based proportional pressure-reducing overflow valve |
| CN113685388B (en) * | 2021-07-19 | 2023-12-12 | 北京天玛智控科技股份有限公司 | Water-based proportional pressure-reducing overflow valve |
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