CN108799234B - Circulation buffering flow control hydraulic valve - Google Patents
Circulation buffering flow control hydraulic valve Download PDFInfo
- Publication number
- CN108799234B CN108799234B CN201810737963.8A CN201810737963A CN108799234B CN 108799234 B CN108799234 B CN 108799234B CN 201810737963 A CN201810737963 A CN 201810737963A CN 108799234 B CN108799234 B CN 108799234B
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- valve
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- valve core
- hydraulic
- buffer
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- 230000003139 buffering effect Effects 0.000 title abstract description 12
- 230000004044 response Effects 0.000 claims abstract description 16
- 238000004146 energy storage Methods 0.000 claims abstract description 12
- 238000013016 damping Methods 0.000 claims abstract description 8
- 239000003921 oil Substances 0.000 description 94
- 239000010720 hydraulic oil Substances 0.000 description 17
- 230000009471 action Effects 0.000 description 11
- 238000000034 method Methods 0.000 description 7
- 230000008569 process Effects 0.000 description 5
- 230000006837 decompression Effects 0.000 description 4
- 230000005611 electricity Effects 0.000 description 3
- 238000005461 lubrication Methods 0.000 description 3
- 239000010729 system oil Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 239000013589 supplement Substances 0.000 description 2
- 239000000428 dust Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000001502 supplementing effect Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
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
- F15B13/023—Excess flow valves, e.g. for locking cylinders in case of hose burst
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention discloses a circulating buffer flow control hydraulic valve. The circulation buffer flow control hydraulic valve includes: the hydraulic valve comprises a handle, a pressure reducing valve group, a handle spring connecting rod, a main valve body, a rear valve cover, an electromagnetic coil, a main valve core spring, a main valve core, a circulating loop valve core, a front valve cover, a balance oil drain valve, a response buffer valve, an impact unloading valve, damping, buffer energy storage assistance and a special-shaped oil way. The invention provides a circulation buffering flow control hydraulic valve, which solves the problem that reverse rotation hydraulic impact and inertial rotation generated by a rotary load executing element powered by a hydraulic system cause vacuum air intake in a pipeline of the hydraulic element after the hydraulic system is stopped.
Description
Technical Field
The invention belongs to the field of hydraulic system control, and particularly relates to a circulation buffering flow control hydraulic valve.
Background
When the high-speed rotating executing element is stopped, larger rotational inertia is generated due to the inertia of the executing element, external braking control rotation is needed to be added on the working condition occasion of accurate control or timely stopping, but the system control generally adopts a driving element to stop power output under the condition that the rotating executing element is stopped without stopping immediately or the rotating speed is required to stop slowly, and the rotating executing element rotates by inertia until the mechanical friction stopping method is realized. The hydraulic system is quite common in equipment which is driven by a hydraulic motor to carry out high-rotation-speed and high-torque load and has no requirement of immediate stop, such as a hydraulic motor to drive a fan blade to rotate.
In the hydraulic open system, under the condition that the hydraulic pump is stopped or oil supply of an oil way is cut off, the hydraulic motor is driven to rotate by inertia due to the fact that the load rotates, the hydraulic motor is discharged out of an oil inlet pipeline of the hydraulic motor, partial vacuum of the pipeline is generated, and particularly when a load rotating element is arranged at a high position, vacuum or air entering the hydraulic motor is easier to generate, so that the hydraulic motor is subjected to readily friction and pneumatic under the condition of no hydraulic oil lubrication every time, and the service life is seriously influenced; in the hydraulic closed system, when the hydraulic pump stops or cuts off oil supply of an oil way, the hydraulic oil at an outlet of the hydraulic motor is closed and gathered by load rotation inertia, the pressure rises sharply, a reverse driving hydraulic motor is generated, the load reverses, and in the process, the inner parts of pipelines at two ends of the hydraulic motor are influenced by the stop and the reverse, so that high-pressure impact is generated to damage hydraulic elements and the service life of the pipelines is reduced.
According to the hydraulic system, the load inertial rotation slow stop is realized, the mechanical friction is reduced, the technical problems that impact and vacuum non-lubrication starting are generated due to inversion in a hydraulic system are solved, the circulating buffering flow control hydraulic valve is provided, the flow and the pressure of hydraulic oil between the control valve and a hydraulic motor are utilized, the hydraulic system is subjected to hydraulic reversing cutting or stopping, the flow active mode circulation is designed, the rotation speed is slowed down through the hydraulic oil flowing resistance, and the bypass buffering hydraulic combination device is arranged between a working oil way and an oil return oil way, so that the effects of reducing inversion impact and supplementing pipeline oil are achieved.
Disclosure of Invention
The invention aims to solve the technical problem that a hydraulic motor in a hydraulic system drives a rotating element to generate continuous rotation or instant reverse rotation due to inertia of a rotating load when power supply is stopped and external braking is not generated; when the hydraulic motor continues to rotate (in an open hydraulic system), the pipeline discharges oil from the pipeline due to the passive rotation of the hydraulic motor, vacuum is generated in the pipeline or the oil shortage condition occurs in the hydraulic motor part, so that the hydraulic motor is damaged due to the mechanical friction of oil-free lubrication when the hydraulic motor is restarted; when the instantaneous reverse rotation (in a closed hydraulic system) hydraulic pump stops oil supply or cuts off an oil supply circuit, the instantaneous high pressure is generated in the pipeline due to the passive rotation of the hydraulic motor, so that the hydraulic motor reversely rotates to a certain extent, the pipeline forms high pressure impact again, and the hydraulic element and the hydraulic oil pipe are damaged.
In order to solve the technical problems, the invention provides the following technical scheme:
A circulation buffering flow control hydraulic valve comprises a handle, a pressure reducing valve group, a handle spring connecting rod, a main valve body, a rear valve cover, an electromagnetic coil, a main valve core spring, a main valve core, a circulation loop valve core, a front valve cover, a balance oil drain valve, a response buffering valve, an impact unloading valve, damping, buffering energy storage assistance, a reset spring and L1, L2, L3 and L4 abnormal-shaped oil ways; one end of the main valve core is connected with the handle, and the other end of the main valve core is sequentially connected with the main valve core spring and the electromagnetic coil; one end of the circulating loop valve core is connected with the reset spring, and the other end of the circulating loop valve core is connected with the response buffer valve; a through hole for connecting the working oil port and the oil return path is arranged in the circulating loop valve core, and one end of the through hole is communicated with an inner hole of the response buffer valve and is connected with an inclined section of the response buffer valve; the impact unloading valve, the buffer energy storage auxiliary and the balance oil drain valve are sequentially connected to form a working oil way and a bypass oil way of an oil return oil way; the outlet of the pressure reducing valve group is communicated with the L1 oil way, so that high-pressure oil at the P port is reduced in pressure and then introduced into one end of the main valve core, and the movement of the main valve core is controlled in an auxiliary manner; the damping is arranged in an L3 special-shaped oil way, the valve core of the circulation loop is controlled to move under low flow and low pressure, and the excessive high-pressure oil flowing into one end of the valve core of the circulation loop is cut off under high flow and high pressure.
Preferably, the buffer energy storage auxiliary interface is provided with an energy storage connection interface.
When the system stops running, an electromagnetic coil at one end of a main valve core of the circulating buffer flow control hydraulic valve is powered off, the main valve core is lowered due to the oil pressure of an oil control cavity, and the main valve core spring pushes and moves, so that the main valve core cuts off a passage between an oil supply (P port) oil way and working oil ways (A port and B port) of the system; meanwhile, under the action of a return spring and the oil pressure reduction, the valve core of the circulation loop is pushed to move by the response of the buffer valve, so that the through hole of the valve core of the circulation loop is communicated with the oil paths of the port A and the port B; the process realizes that original hydraulic oil passes through the main valve core from the P port to the A port, the A port passes through the B port, the B port passes through the T port, the process of connecting the A port and the B port by the internal oil hole of the circulation loop valve core is converted, the hydraulic oil forms circulation flow at the A port oil way, the B port oil way and the internal oil hole of the circulation loop valve core along with the inertial rotation of a load, the internal oil hole of the circulation loop valve core slowly reduces the hydraulic flow rate, thereby slowing down the rotation speed and ensuring that the pipeline is full of hydraulic oil during the final shutdown.
When the system generates high-pressure load in the moment of reverse rotation or stop of the hydraulic motor, the high-pressure impact is buffered by the impact unloading valve, the buffer energy storage auxiliary interface, the balance oil drain valve and the L4 oil way, and the oil pressure of the pipeline is balanced.
The invention provides a circulation buffering flow control hydraulic valve, which solves the problem that reverse rotation hydraulic impact and inertial rotation generated by a rotary load executing element for providing power for a hydraulic system cause vacuum air intake in a pipeline of the hydraulic element.
Drawings
The following is further described in conjunction with the accompanying drawings and detailed description:
FIG. 1 is a schematic diagram of the structure of a cyclical buffering flow control hydraulic valve of the present invention;
In the figure: 1. the handle, the pressure reducing valve group, the handle spring connecting rod, the main valve body, the rear valve cover, the electromagnetic coil, the main valve core spring, the main valve core, the circulating loop valve core and the valve core are respectively arranged in sequence, 10, a front valve cover, 11, a balance oil drain valve, 12, a response buffer valve, 13, an impact unloading valve, 14, damping, 15, a buffer energy storage auxiliary interface and 16, a return spring.
FIG. 2 is a schematic illustration of a main spool (8) of the cyclical buffer flow control hydraulic valve of the present invention;
In the figure: 81. and an oil control cavity.
FIG. 3 is a schematic view of the circulation loop spool (9) of the circulation buffer flow control hydraulic valve of the present invention;
In the figure: 91. through hole, 92. Reset cavity.
Detailed Description
As shown in figures 1-3, the invention discloses a circulating buffer flow control hydraulic valve, which mainly comprises a handle 1, a pressure reducing valve group 2, a handle spring connecting rod 3, a main valve body 4, a rear valve cover 5, an electromagnetic coil 6, a main valve core spring 7, a main valve core 8, a circulating loop valve core 9, a front valve cover 10, a balance oil drain valve 11, a response buffer valve 12, an impact unloading valve 13, a damping 14, a buffer energy storage auxiliary interface 15 and a return spring 16. L1, L2 and L3 shown in the figure are special-shaped oil passages in the main valve body 4, L4 is a special-shaped oil passage of the rear valve cover, and the special-shaped oil passage is formed by processing a plurality of process holes.
The main valve body 4 is provided with three mounting surfaces which are respectively connected with the mounting surfaces of the pressure reducing valve group 2, the rear valve cover 5 and the front valve cover 10 to form a dust collection circulation buffering flow control hydraulic valve whole. One end of the main valve body 4 is connected with the front valve cover, the other end is connected with the rear valve cover, and the top of the main valve body is connected with the pressure reducing valve group.
The handle 1, the handle spring 3 and the main valve core 8 are connected into a three-link mechanism, so that control operations of different positions of the main valve core 1 can be realized.
One end of a main valve core 8 is connected with the handle 1, the other end of the main valve core 8 is sequentially connected with a main valve core spring 7 and an electromagnetic coil 6, and 3 working positions are formed under the force action of the handle spring 3, the force action of the main valve core spring 7, the force action of the electromagnetic coil 6 and the force action of oil pressure on the sectional area under different working conditions: normal position (zero reset state), low flow floating state position (transition state), working position.
One end of the circulation loop valve core 9 is connected with a return spring 16 at the front valve cover 10, the other end of the circulation loop valve core 9 is connected with a response buffer valve 12 at the rear valve cover 10, and the circulation loop valve core 9 forms 3 working positions under the force action of the return spring 16, the force action of the response buffer valve 12 and the force action of the pressure of a control oil cavity 81 of the return spring 16: normal position (a state in which the port a pipe communicates with the port B pipe, in parallel with the operating state of the main spool 8), floating state position (in parallel with the low flow floating state of the main spool 8), operating state position (in parallel with the normal state of the main spool 8). When the working A oil way and the working B oil way are stopped, the flow speed is slowly and circularly slowed down to reach the stop of load through the action of the circulating loop valve core 9 and the response buffer valve 12, and the pipeline is ensured to be full of hydraulic oil.
The buffer energy storage auxiliary 15 is formed by connecting an L4 oil way with the impact unloading valve 13 and the balance oil drain valve 11, so as to buffer oil return impact (oil return impact is generated when the closed system is reversed), unload the surplus flow of the working oil way and realize balance of the oil pressure and oil supplement of the working oil way.
The working principle of the circulation buffer flow control hydraulic valve is as follows:
Under the normal state of the circulating buffer flow control hydraulic valve, when the P port is not pressurized and the electromagnetic coil 6 is not electrified, the main valve core 8 is reset to the normal position through the resultant force of the main valve core reset spring 7 and the handle connecting rod spring 3, at the moment, the P port oil way of the circulating buffer flow control hydraulic valve is cut off and connected with a power oil supply pipeline, the T port oil way is cut off and connected with an oil tank pipeline, the circulating loop valve core 9 is under the action of the reset spring 16 responding to the buffer valve 12 and the circulating loop valve core 9, the hydraulic oil of the A port oil way and the B port oil way is communicated through the circulating buffer valve core 9, and the state enables a rotary executing element connected with the A port oil way and the B port oil way to maintain that the pipeline and the hydraulic motor are filled with the hydraulic oil under the lower hydraulic self flow resistance.
The system supplies oil, namely hydraulic oil is supplied to the port P, so that the oil pressure at the port P rises, and when the electromagnetic coil 6 is not electrified, the hydraulic oil at the port P is decompressed through the decompression valve group 2, enters the oil control cavity 81 of the main valve core through the L1 oil way, then enters the reset cavity 92 where the reset spring 16 is positioned through the L3 oil way through the damping 14 in a decompression way, the action resultant force of the reset spring 16 and the decompression oil pressure of the circulating loop valve core 9 is balanced with the acting force of the response buffer valve 12, and the passage communicated between the oil way at the port A and the oil way at the port B of the circulating loop valve core 9 is closed; as the oil pressure of the port P rises, the main valve core 8 reaches a set decompression upper limit value by the oil pressure of the oil control cavity 81, the oil pressure acting force of the oil control cavity 81 is balanced with the acting force of the main valve core spring 7, and the main valve core 8 reaches a low-flow floating state position, so that hydraulic oil is supplemented to the pipeline oil of the port a and the pipeline oil of the port B from the port P, and excessive hydraulic oil flows to the oil path unloading of the port T through the impact unloading 13, the pipeline L4 and the balance oil drain valve 11 which are connected with the port B. At this time, the main spool 8 is maintained in a small flow floating state, and the port a and port B connecting lines are filled with hydraulic oil.
When the system supplies oil, when the electromagnetic coil 6 is electrified, the main valve core 8 moves to a working position state due to the acting force of the electromagnetic coil 6, the P port oil way leads to the A port oil way, and the B port oil way leads to the T port oil way. The rotating load element or the fan blade operates.
The operation sequence of stopping the operation of the rotary actuator is to control the electromagnetic coil 6 to lose electricity and stop the system oil supply. When the electromagnetic coil 6 is controlled to lose electricity, the rotation of the rotary load element or the fan blade is represented as the rotation speed of the rotation to be reduced; when the system oil supply is stopped, the rotating speed of the rotary load element or the fan blade is further slowly and gradually stopped.
Fig. 1 is a schematic diagram of a circulation buffer flow control hydraulic valve according to the present invention, and the control method of the embodiment is applicable to closed and open hydraulic systems. According to the hydraulic pump, as shown in the figure, a P port and a T port are respectively connected with an oil outlet and an oil return port of a hydraulic pump source, and an A port and a B port are respectively connected with an oil inlet and an oil outlet of a hydraulic motor. Especially for closed system, when the electromagnetic coil 6 of the circulation buffer flow control hydraulic valve loses electricity and stops the system oil supply, the B port pipeline is instantly boosted due to the inertia of the rotary load element, the rotary element is reversely rotated to a certain degree, and the instant peak value in the process has influence on the pipeline and the hydraulic motor. The invention relates to a circulating buffer flow control hydraulic valve, which solves the problem that the impact unloading 13 at the port B and a balance oil drain valve 11 realize buffer impact, and is additionally provided with a buffer energy storage auxiliary interface 15 which is connected with the corresponding high pressure of an energy accumulator at the buffer moment and supplements leakage hydraulic oil according to the impact degree. The handle 1 is used for emergency control.
Finally, it should be noted that: the foregoing description is only a preferred embodiment of the present invention, and the present invention is not limited thereto, but it is to be understood that modifications and equivalents of some of the technical features described in the foregoing embodiments may be made by those skilled in the art, although the present invention has been described in detail with reference to the foregoing embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (2)
1. A circulation buffer flow control hydraulic valve, characterized in that: the hydraulic control valve comprises a handle (1), a pressure reducing valve group (2), a handle spring connecting rod (3), a main valve body (4), a rear valve cover (5), an electromagnetic coil (6), a main valve core spring (7), a main valve core (8), a circulating loop valve core (9), a front valve cover (10), a balance oil drain valve (11), a response buffer valve (12), an impact unloading valve (13), a damping valve (14), a buffer energy storage auxiliary interface (15), a return spring (16) and L1, L2, L3 and L4 special-shaped oil ways; one end of the main valve core (8) is connected with the handle (1), and the other end of the main valve core is sequentially connected with the main valve core spring (7) and the electromagnetic coil (6); one end of the circulation loop valve core (9) is connected with a return spring (16), and the other end of the circulation loop valve core is connected with a response buffer valve (12); a through hole (91) for connecting the working oil port and the oil return path is arranged in the circulation loop valve core (9), one end of the through hole (91) is communicated with an inner hole of the response buffer valve (12) and is connected with an inclined section of the response buffer valve (12); the impact unloading valve (13), the buffer energy storage auxiliary interface (15) and the balance oil drain valve (11) are sequentially connected to form a working oil way and a bypass oil way of an oil return oil way; the outlet of the pressure reducing valve group (2) is communicated with an L1 oil way, so that high-pressure oil at the P port is reduced in pressure and then introduced into one end of the main valve core, and the movement of the main valve core (8) is controlled in an auxiliary manner; the damping (14) is arranged in an L3 special-shaped oil way, the valve core (9) of the circulation loop is controlled to move under low flow and low pressure, and the excessive high-pressure oil flowing into one end of the valve core (9) of the circulation loop is cut off under high flow and high pressure.
2. The circulation buffer flow control hydraulic valve according to claim 1, characterized in that the buffer storage auxiliary connection (15) is provided with an accumulator connection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810737963.8A CN108799234B (en) | 2018-07-06 | 2018-07-06 | Circulation buffering flow control hydraulic valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810737963.8A CN108799234B (en) | 2018-07-06 | 2018-07-06 | Circulation buffering flow control hydraulic valve |
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| Publication Number | Publication Date |
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| CN108799234A CN108799234A (en) | 2018-11-13 |
| CN108799234B true CN108799234B (en) | 2024-05-10 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201810737963.8A Active CN108799234B (en) | 2018-07-06 | 2018-07-06 | Circulation buffering flow control hydraulic valve |
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| CN109578298B (en) * | 2019-01-23 | 2024-03-19 | 宋丽丽 | Hydraulic control start-stop full-automatic anti-collision fan motor |
| CN110273392B (en) * | 2019-04-16 | 2021-11-05 | 四川大学 | Self-adaptive lifting deceleration strip |
| CN112648251B (en) * | 2020-12-22 | 2023-04-28 | 天水锻压机床(集团)有限公司 | Automatic fluid infusion hydraulic valve of accumulator for large bending machine |
| CN113217496B (en) * | 2021-05-19 | 2022-06-14 | 宁波隆而法液压有限公司 | Hydraulic valve with function of controlling liquid flow speed and using method |
| CN116044742B (en) * | 2023-03-28 | 2023-06-20 | 常州凯鹏液流器材有限公司 | Radiator adopting oil pump system and working method thereof |
| CN116447190B (en) * | 2023-06-14 | 2023-09-08 | 江苏曹工液压科技有限公司 | Hydraulic valve capable of flexibly reversing |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4555974A (en) * | 1983-09-02 | 1985-12-03 | Pneumo Corporation | Servo actuator control/damping mechanism and method |
| CN102777438A (en) * | 2012-08-17 | 2012-11-14 | 邓开忠 | Multifunctional integrated valve bank of hydraulic motor |
| EP3029325A1 (en) * | 2014-12-02 | 2016-06-08 | Mitsubishi Heavy Industries, Ltd. | Spool valve, hydraulic machine, and wind turbine power generating apparatus |
| CN107672575A (en) * | 2017-09-01 | 2018-02-09 | 金勇� | Electric control braking valve |
| CN208764011U (en) * | 2018-07-06 | 2019-04-19 | 秦皇岛首创思泰意达环保科技有限公司 | A kind of circular buffering flow control hydraulic valve |
-
2018
- 2018-07-06 CN CN201810737963.8A patent/CN108799234B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4555974A (en) * | 1983-09-02 | 1985-12-03 | Pneumo Corporation | Servo actuator control/damping mechanism and method |
| CN102777438A (en) * | 2012-08-17 | 2012-11-14 | 邓开忠 | Multifunctional integrated valve bank of hydraulic motor |
| EP3029325A1 (en) * | 2014-12-02 | 2016-06-08 | Mitsubishi Heavy Industries, Ltd. | Spool valve, hydraulic machine, and wind turbine power generating apparatus |
| CN107672575A (en) * | 2017-09-01 | 2018-02-09 | 金勇� | Electric control braking valve |
| CN208764011U (en) * | 2018-07-06 | 2019-04-19 | 秦皇岛首创思泰意达环保科技有限公司 | A kind of circular buffering flow control hydraulic valve |
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| CN108799234A (en) | 2018-11-13 |
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