CN111677623B - Control valve device with override control for pressure difference between inlet and outlet of induction motor - Google Patents
Control valve device with override control for pressure difference between inlet and outlet of induction motor Download PDFInfo
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- CN111677623B CN111677623B CN202010564608.2A CN202010564608A CN111677623B CN 111677623 B CN111677623 B CN 111677623B CN 202010564608 A CN202010564608 A CN 202010564608A CN 111677623 B CN111677623 B CN 111677623B
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03C—POSITIVE-DISPLACEMENT ENGINES DRIVEN BY LIQUIDS
- F03C1/00—Reciprocating-piston liquid engines
- F03C1/02—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders
- F03C1/06—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders with cylinder axes generally coaxial with, or parallel or inclined to, main shaft axis
- F03C1/061—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders with cylinder axes generally coaxial with, or parallel or inclined to, main shaft axis having stationary cylinders
- F03C1/0615—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders with cylinder axes generally coaxial with, or parallel or inclined to, main shaft axis having stationary cylinders distributing members
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03C—POSITIVE-DISPLACEMENT ENGINES DRIVEN BY LIQUIDS
- F03C1/00—Reciprocating-piston liquid engines
- F03C1/02—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders
- F03C1/06—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders with cylinder axes generally coaxial with, or parallel or inclined to, main shaft axis
- F03C1/061—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders with cylinder axes generally coaxial with, or parallel or inclined to, main shaft axis having stationary cylinders
- F03C1/0613—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders with cylinder axes generally coaxial with, or parallel or inclined to, main shaft axis having stationary cylinders having two or more sets of cylinders or pistons
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03C—POSITIVE-DISPLACEMENT ENGINES DRIVEN BY LIQUIDS
- F03C1/00—Reciprocating-piston liquid engines
- F03C1/02—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders
- F03C1/06—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders with cylinder axes generally coaxial with, or parallel or inclined to, main shaft axis
- F03C1/0678—Control
Abstract
The invention discloses a control valve device with override control for sensing the pressure difference between an inlet and an outlet of a motor, which comprises a pressure difference valve connected with a working oil port of a variable motor, wherein the pressure difference valve is respectively connected with a small variable piston and a constant pressure control valve, and the constant pressure control valve is connected with a large variable piston; the constant-pressure control valve is also connected with an oil return port and a control oil port; the small variable piston is also connected with a return spring. The invention connects a differential pressure valve in series with the original constant pressure control valve structure, the differential pressure valve not only completes the function of the original motor inlet and outlet one-way valve, but also ensures that the tail part (without a pressure regulating spring end) of the valve core of the constant pressure control valve is kept to be connected with the inlet high pressure and the front end (with the pressure regulating spring end) of the valve core of the constant pressure control valve is kept to be connected with the outlet low pressure when the pressure of the inlet and the outlet is switched, so that the opening of the constant pressure control valve forms differential pressure control, thereby effectively avoiding the influence of the oil pressure of an oil return cavity on the opening of the existing constant pressure control valve.
Description
Technical Field
The invention relates to a straight shaft type axial plunger variable motor device, in particular to a control valve device with override control for sensing the pressure difference of an inlet and an outlet of a motor.
Background
The axial plunger motor is a commonly used execution element in a hydraulic transmission system, for the axial plunger motor with constant pressure control, the opening pressure of a constant pressure valve is related to the pretightening force, the outlet pressure and the oil return pressure of a spring, a host hopes that the motor can output corresponding torque when the constant pressure valve is opened, however, the torque output by the motor is different from a set value due to the fact that the outlet pressure and the oil return pressure of the motor are different under different working conditions, particularly in precise hydraulic control systems such as spaceflight and aviation, the working condition of the motor is complex, the oil return pressure of a shell cavity is high, the opening of the constant pressure control valve is obviously affected by external factors, the anti-interference capability is poor, further, the actual action of an execution mechanism is inconsistent with an expected control result, and even a safety accident occurs in severe cases. Therefore, the prior art has the problems of poor anti-interference capability and low reliability of a control system.
Disclosure of Invention
The invention aims to provide a control valve device with override control for sensing the pressure difference between an inlet and an outlet of a motor. The invention has the characteristics of strong anti-interference capability and capability of effectively improving the reliability of the control system.
The technical scheme of the invention is as follows: a control valve device with override control for sensing the pressure difference between an inlet and an outlet of a motor comprises a pressure difference valve connected with a working oil port of a variable motor, wherein the pressure difference valve is respectively connected with a small variable piston and a constant pressure control valve, and the constant pressure control valve is connected with a large variable piston; the constant-pressure control valve is also connected with an oil return port and a control oil port; the small variable piston is also connected with a return spring.
In the control valve device for the pressure difference between the inlet and the outlet of the induction motor with the override control, the variable displacement motor comprises a swash plate, and one end of the swash plate is provided with a plunger and a rotor; the small variable piston and the large variable piston are respectively positioned at two sides of the other end of the swash plate.
In the control valve device with the override control for the pressure difference between the inlet and the outlet of the induction motor, the pressure difference valve is vertically arranged on the central line of the oil inlet and the oil outlet of the oil distribution cover of the variable motor and is arranged in parallel with the constant pressure control valve.
In the control valve device with the override control for the pressure difference between the inlet and the outlet of the induction motor, the pressure difference valve comprises a pressure difference valve sleeve positioned in the variable motor oil distribution cover, a pressure difference valve core is arranged in the pressure difference valve sleeve, pressure difference valve plugs are arranged at two ends of the pressure difference valve core, and a plug is further arranged at the outer end of one of the pressure difference valve plugs; and the differential pressure valve sleeve is provided with a first oil hole, a second oil hole and a third oil hole.
In the control valve device with the override control for the inlet-outlet differential pressure of the induction motor, the constant-pressure control valve comprises a valve body, a constant-pressure control valve sleeve is arranged in the valve body, a constant-pressure control valve core is arranged in the constant-pressure control valve sleeve, a pressure regulating spring is arranged at the front end of the constant-pressure control valve core, and an override control valve core is arranged at the tail end of the constant-pressure control valve core.
In the control valve device with the override control for the pressure difference between the inlet and the outlet of the induction motor, the outer end of the pressure regulating spring is provided with the pressure regulating screw.
In the above control valve device with override control for the pressure difference between the inlet and the outlet of the induction motor, the valve body is provided with a pipe joint at the valve core end of the override control valve, and the pipe joint corresponds to the control oil port.
In the above control valve device with override control for the pressure difference between the inlet and the outlet of the induction motor, the first oil hole and the third oil hole correspond to the front end face of the constant-pressure control valve element, and the second oil hole corresponds to the rear end face of the constant-pressure control valve element.
Compared with the prior art, the constant pressure control valve structure is characterized in that a pressure difference valve is connected in series with the original constant pressure control valve structure, the pressure difference valve not only fulfills the function of an inlet and outlet one-way valve of an original motor, but also ensures that the tail part (without a pressure regulating spring end) of a valve core of the constant pressure control valve is kept to be communicated with the high pressure of an inlet and the front end (with the pressure regulating spring end) of the valve core of the constant pressure control valve is kept to be communicated with the low pressure of an outlet when the pressure of the inlet and the pressure of the outlet are switched, so that the opening of the constant pressure control valve forms pressure difference control, the opening of the constant pressure control valve can be effectively prevented from being influenced by the oil pressure of an oil return cavity, meanwhile, the opening pressure of the constant pressure valve is fed back by the pressure of the outlet, and the opening pressure of the constant pressure valve is higher when the outlet pressure of the motor is higher, and vice versa. The opening of the constant-pressure control valve can form differential pressure control, the opening of the existing constant-pressure control valve is prevented from being influenced by the oil pressure of the oil return cavity, the opening pressure of the constant-pressure control valve is also fed back by the outlet pressure, the constant-pressure control valve has the characteristic of high anti-interference capacity, and the reliability of the onboard control system can be improved. The invention also adds a priority override control function on the basis of the existing constant pressure valve structure to ensure that the motor of the airborne system is switched to the maximum displacement under the emergency working condition, thereby further improving the reliability of the airborne control system. The invention can be applied to the precise control of engineering machinery, and can also be applied to hydraulic systems with large return oil pressure and outlet pressure fluctuation, such as aerospace and aviation. In conclusion, the invention has the characteristics of strong anti-interference capability and capability of effectively improving the reliability of the control system.
Drawings
FIG. 1 is a hydraulic control schematic of the present invention;
FIG. 2 is a cross-sectional construction view of a motor embodying the present invention;
FIG. 3 is a cross-sectional configuration view of the differential pressure valve of the present invention;
FIG. 4 is a schematic diagram of the oil circuit structure in the constant pressure control valve;
fig. 5 is a graph of the output characteristics of the straight axis axial piston motor of the present invention.
The labels in the figures are: 1-variable motor, 2-differential pressure valve, 3-small variable piston, 4-constant pressure control valve, 5-large variable piston, 6-return spring, 7-swash plate, 8-plunger, 9-rotor, 201-differential pressure valve sleeve, 202-differential pressure valve core, 203-differential pressure valve plug, 204-plug, 205-first oil hole, 206-second oil hole, 207-third oil hole, 401-valve body, 402-constant pressure control valve sleeve, 403-constant pressure control valve core, 404-pressure regulating spring, 405-override control valve core, 406-pressure regulating screw and 407-pipe joint.
Detailed Description
The invention is further illustrated by the following figures and examples, which are not to be construed as limiting the invention.
Examples are given. A control valve device with override control for the pressure difference between the inlet and the outlet of an induction motor is formed as shown in figures 1 to 5 and comprises a pressure difference valve 2 connected with a working oil port of a variable motor 1, wherein the pressure difference valve 2 is respectively connected with a small variable piston 3 and a constant pressure control valve 4, and the constant pressure control valve 4 is connected with a large variable piston 5; the constant pressure control valve 4 is also connected with an oil return port and a control oil port; the small variable piston 3 is also connected with a return spring 6.
The variable displacement motor 1 comprises a swash plate 7, and one end of the swash plate 7 is provided with a plunger 8 and a rotor 9; the small variable piston 3 and the large variable piston 5 are respectively positioned on both sides of the other end of the swash plate 7.
The differential pressure valve 2 is vertically arranged on the central line of the oil inlet and outlet of the variable motor oil distribution cover and is arranged in parallel with the constant pressure control valve 4.
The differential pressure valve 2 comprises a differential pressure valve sleeve 201 positioned in an oil distribution cover of the variable motor, a differential pressure valve core 202 is arranged in the differential pressure valve sleeve 201, differential pressure valve plugs 203 are arranged at two ends of the differential pressure valve core 202, and a plug 204 is arranged at the outer end of one differential pressure valve plug 203; the differential pressure valve sleeve 201 is provided with a first oil hole 205, a second oil hole 206 and a third oil hole 207.
The constant pressure control valve 4 comprises a valve body 401, a constant pressure control valve sleeve 402 is arranged in the valve body 401, a constant pressure control valve spool 403 is arranged in the constant pressure control valve sleeve 402, a pressure regulating spring 404 is arranged at the front end of the constant pressure control valve spool 403, and an override control valve spool 405 is arranged at the tail end of the constant pressure control valve spool 403.
The outer end of the pressure regulating spring 404 is provided with a pressure regulating screw 406.
The valve body 401 is provided with a pipe joint 407 at the valve core 405 end of the override valve, and the pipe joint 407 corresponds to the control oil port.
The first oil hole 205 and the third oil hole 207 correspond to a leading end surface of the constant pressure control valve spool 403, and the second oil hole 206 corresponds to a trailing end surface of the constant pressure control valve spool 403.
Fig. 3 is a sectional view showing a differential pressure valve according to an embodiment of the present invention, in which a first oil hole, a second oil hole, and a third oil hole are provided in a differential pressure valve housing, the first oil hole and the third oil hole are oil passages leading to a front end surface of a spool of a constant pressure control valve, the second oil hole is an oil passage leading to a rear end surface of the spool of the constant pressure control valve, and pa (pb) and pb (pa) are oil pressures communicated with an inlet of a motor, respectively.
When the working oil port A is high-pressure oil at the inlet of the motor, the valve core of the differential pressure valve descends, the high-pressure oil at the port A is led to the left end of the constant-pressure control valve through the differential pressure valve, the low-pressure oil at the outlet of the working oil port B of the motor is low-pressure oil at the moment, and the low-pressure oil at the port B is led to the right end of the constant-pressure control valve through the constant-pressure valve. When the working oil port B is high-pressure oil at the inlet of the motor, the valve core of the differential pressure valve ascends, high-pressure oil at the port B is led to the left end of the constant-pressure control valve through the differential pressure valve, low-pressure oil at the port A of the motor is low-pressure oil at the outlet, and low-pressure oil at the port A is led to the right end of the constant-pressure control valve through the constant-pressure valve, so that when the motor switches between the high-pressure oil and the low-pressure oil, the left end of the valve core of the constant-pressure control valve is kept to be connected with high pressure, and the right end of the valve core of the constant-pressure control valve is kept to be connected with low pressure to form differential pressure control.
The specific variable control process is as follows:
as shown in figure 2, the differential pressure valve is vertically arranged on the central line of the oil inlet and outlet of the motor oil distributing cover and is arranged in parallel with the constant pressure control valve, so that the arrangement is convenient for leading oil at the inlet and the outlet of the motor to the differential pressure valve and is also beneficial for leading working oil passing through the differential pressure valve to the front end and the rear end of the valve core of the constant pressure control valve.
As shown in fig. 3, the sectional structure diagram of fig. 3 is a structure diagram of the invention according to the principle diagram of fig. 1, the valve sleeves of the differential pressure valves are respectively positioned by two differential pressure valve plugs, one differential pressure valve plug is positioned at the end surface of the valve hole of the oil distributing cover, and the differential pressure plug at the other end is positioned at the plug.
T is an oil return tank.
When the right end of the differential pressure control valve is communicated with motor inlet high-pressure oil Pa, the left end Pb of the differential pressure valve is communicated with corresponding motor outlet low-pressure oil, because the oil pressure of the motor inlet is higher than that of the outlet, under the condition that the areas of the left end and the right end of the valve core of the differential pressure valve are equal, the valve core of the differential pressure valve moves leftwards until the valve core is screwed and limited by the left end differential pressure valve, at the moment, the first oil hole is cut off by the valve core of the differential pressure valve, an oil way hole leading to the tail end face of the valve core of the constant pressure valve control valve is communicated with Pa, and meanwhile, Pb oil communicated with the motor outlet oil enters the front end face of the valve core of the constant pressure control valve through the third oil hole.
When the left end of the differential pressure control valve is communicated with motor inlet high-pressure oil Pb, the right end Pa of the differential pressure valve is communicated with corresponding motor outlet low-pressure oil, the spool of the differential pressure valve moves rightwards until the differential pressure valve is screwed and limited by the right differential pressure valve, at the moment, the third oil hole is cut off by the spool of the differential pressure valve, the second oil hole communicated with the tail end face of the spool of the constant pressure valve control valve is communicated with Pb, and meanwhile, the Pa oil communicated with the motor outlet oil enters the front end face of the spool of the constant pressure control valve through the first oil hole.
As shown in FIG. 4, no matter how the inlet oil and the outlet oil are switched, the oil on the tail end surface of the valve core of the constant pressure control valve is directly communicated with the inlet oil of the motor, and the oil on the front end surface of the valve core of the constant pressure control valve is directly communicated with the outlet oil of the motor, so that the pressure difference control is formed by the constant pressure control valve. The constant pressure valve is additionally provided with an override control valve core, and because the cross-sectional area of the override control valve core is larger than that of the tail end face of the constant pressure control valve core, when an X port (a control oil port) is connected with lower control oil pressure, the valve core can overcome the left position movement of a pressure regulating spring, and the oil pressure at the inlet of a motor is led to a large-displacement piston through the constant pressure control valve, so that the large-displacement change of a swash plate under the condition of lower pressure oil at the inlet of the motor is realized.
Claims (4)
1. The utility model provides a take induction motor of unauthorized control to import and export pressure differential's control valve device which characterized in that: the variable displacement hydraulic pump comprises a differential pressure valve (2) connected with a working oil port of a variable motor (1), wherein the differential pressure valve (2) is respectively connected with a small variable piston (3) and a constant pressure control valve (4), and the constant pressure control valve (4) is connected with a large variable piston (5); the constant-pressure control valve (4) is also connected with an oil return port and a control oil port; the small variable piston (3) is also connected with a return spring (6);
a swash plate (7) is arranged in the variable motor (1), and a plunger (8) and a rotor (9) are arranged at one end of the swash plate (7); the small variable piston (3) and the large variable piston (5) are respectively positioned at two sides of the other end of the swash plate (7);
the differential pressure valve (2) is vertically arranged on the central line of the oil inlet and outlet of the variable motor oil distribution cover and is arranged in parallel with the constant pressure control valve (4);
the differential pressure valve (2) comprises a differential pressure valve sleeve (201) positioned in the variable motor oil distribution cover, a differential pressure valve spool (202) is arranged in the differential pressure valve sleeve (201), differential pressure valve plugs (203) are arranged at two ends of the differential pressure valve spool (202), and a plug (204) is further arranged at the outer end of one differential pressure valve plug (203); a first oil hole (205), a second oil hole (206) and a third oil hole (207) are formed in the differential pressure valve sleeve (201);
the constant-pressure control valve (4) comprises a valve body (401), a constant-pressure control valve sleeve (402) is arranged in the valve body (401), a constant-pressure control valve spool (403) is arranged in the constant-pressure control valve sleeve (402), a pressure regulating spring (404) is arranged at the front end of the constant-pressure control valve spool (403), and an override control valve spool (405) is arranged at the tail end of the constant-pressure control valve spool (403);
when the pressure of the inlet and the pressure of the outlet are switched, the differential pressure valve connected with the working oil port of the variable motor is used for maintaining the connection of the tail of the valve core of the constant pressure control valve with the high pressure of the inlet and maintaining the connection of the front end of the valve core of the constant pressure control valve with the low pressure of the outlet, so that the opening of the constant pressure control valve forms differential pressure control.
2. The apparatus of claim 1, wherein the control valve assembly is configured to sense differential pressure across the inlet and outlet of the motor with override control, further comprising: the outer end of the pressure regulating spring (404) is provided with a pressure regulating screw (406).
3. The apparatus of claim 1, wherein the control valve assembly is configured to sense differential pressure across the inlet and outlet of the motor with override control, further comprising: a pipe joint (407) is arranged at the valve core (405) end of the valve body (401) of the override control valve, and the pipe joint (407) corresponds to the control oil port.
4. The apparatus of claim 1, wherein the control valve assembly is configured to sense differential pressure across the inlet and outlet of the motor with override control, further comprising: the first oil hole (205) and the third oil hole (207) correspond to the front end face of the constant pressure control valve spool (403), and the second oil hole (206) corresponds to the rear end face of the constant pressure control valve spool (403).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010564608.2A CN111677623B (en) | 2020-06-19 | 2020-06-19 | Control valve device with override control for pressure difference between inlet and outlet of induction motor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010564608.2A CN111677623B (en) | 2020-06-19 | 2020-06-19 | Control valve device with override control for pressure difference between inlet and outlet of induction motor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111677623A CN111677623A (en) | 2020-09-18 |
| CN111677623B true CN111677623B (en) | 2022-04-22 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010564608.2A Active CN111677623B (en) | 2020-06-19 | 2020-06-19 | Control valve device with override control for pressure difference between inlet and outlet of induction motor |
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Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113446280A (en) * | 2021-06-30 | 2021-09-28 | 北京航空航天大学宁波创新研究院 | Bidirectional differential pressure controller and hydraulic equipment |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4418118C1 (en) * | 1994-05-24 | 1995-07-06 | Daimler Benz Ag | Servo steering control for automobile |
| CN2570498Y (en) * | 2002-05-30 | 2003-09-03 | 叶大林 | Cam plate type supporting hydraulic cylinder axial piston pump |
| CN204041575U (en) * | 2014-08-27 | 2014-12-24 | 浙江德泰机电工程有限公司 | A kind of constant-pressure control device for oil hydraulic pump |
| CN104500480B (en) * | 2014-12-29 | 2017-02-22 | 中航力源液压股份有限公司 | High-pressure automatic variable control method with hydraulic overload and control valve device |
| CN204610163U (en) * | 2015-04-23 | 2015-09-02 | 宁波恒力液压股份有限公司 | Double steering constant-pressure variable axial piston pump |
| CN105134578A (en) * | 2015-07-30 | 2015-12-09 | 徐州重型机械有限公司 | Plunger pump with energy recycling function |
| CN207813836U (en) * | 2017-12-05 | 2018-09-04 | 宁波市奉化溪口威尔特制泵厂 | A kind of energy-efficient inclined disc type high-pressure plunger pump |
| CN108644169B (en) * | 2018-05-31 | 2023-10-17 | 中航力源液压股份有限公司 | High-voltage automatic control device integrating priority speed control |
| CN110486339B (en) * | 2019-08-27 | 2021-02-09 | 徐州重型机械有限公司 | Motor control system and crane |
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