CN111795029A

CN111795029A - Linear servo device of hydraulic valve and working method thereof

Info

Publication number: CN111795029A
Application number: CN202010658797.XA
Authority: CN
Inventors: 肖国瑞
Original assignee: Bazhou Yueyate Machinery Manufacturing Co ltd
Current assignee: Bazhou Yueyate Machinery Manufacturing Co ltd
Priority date: 2020-07-09
Filing date: 2020-07-09
Publication date: 2020-10-20

Abstract

The invention discloses a linear servo device of a hydraulic valve and a working method thereof, and the linear servo device comprises an electromagnetic assembly and the hydraulic valve, wherein the electromagnetic assembly comprises a magnetic shell, the inner side of the magnetic shell is sequentially provided with a first armature and a second armature from top to bottom, the first armature comprises a first cylinder, the outer side of the first cylinder is fixedly sleeved with a first excitation coil, the inner side of the first cylinder is fixedly provided with a first armature, the second armature comprises a second cylinder, the outer side of the second cylinder is fixedly sleeved with a second excitation coil, the inner side of the second cylinder is fixedly provided with a second armature, the hydraulic valve comprises a valve shell, the inner side of the valve shell is axially provided with a control piston, the lower end surface of the control piston is provided with a spring accommodating groove, and the inner side of the spring accommodating. According to the invention, the armature core is controlled by the plurality of coils to replace a single-coil direct-current proportional electromagnet, so that the size of the opening can be accurately and slowly controlled, and the phenomenon that a valve core in the hydraulic valve is in a violent motion state is avoided.

Description

Linear servo device of hydraulic valve and working method thereof

Technical Field

The invention relates to the technical field of hydraulic valves, in particular to a linear servo device of a hydraulic valve and a working method thereof.

Background

The control element in hydraulic transmission system of hydraulic valve is a common component in industrial production control, and is used for controlling the direction, pressure and flow of liquid. It is composed of valve body, valve core and liquid flow channel. The control of the valve core can adopt manual, motor, hydraulic, electric, electro-hydraulic and the like, and the electric control is connected with a control circuit, so that the valve core is easy to realize automation and is widely applied. However, in a common electromagnetic valve, a coil is electrified to attract an armature core, the core drives a valve core to move, and the armature core and the valve core are reset by a spring after power failure, so that the on-off of liquid flow is controlled. Due to the fact that the armature core is in great motion impact when being electrified, the controlled object usually undergoes violent change of motion state, and accurate control of the state of the controlled object is not facilitated. Particularly, in the control of the proportional valve, a method for balancing the attraction force of the single coil control armature of the direct-current proportional electromagnet and the spring force is adopted, the opening size is controlled, so that the proportional control speed, the pressure and the flow are achieved, the proportional valve is limited by the change of the spring force and the low control precision.

In the prior art, a single coil is mostly adopted to control the motion of the armature core, the motion speed is not controlled, the time of the displacement of the armature is short, and the control precision is low due to the fact that the motion state changes violently.

Disclosure of Invention

The invention aims to overcome the defects in the prior art, provides a linear servo device of a hydraulic valve and a working method thereof, and can effectively solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides a straight line servo device of hydrovalve, includes electromagnetic component and hydrovalve, the electromagnetic component includes the magnetism shell, the magnetism shell is the cylinder form, the inboard of magnetism shell is from last to being equipped with first armature and second armature down in proper order, first armature includes first barrel, the fixed first excitation coil that has cup jointed in the outside of first barrel, the inboard fixed mounting of first barrel has first armature, the second armature includes the second barrel, the outside of second barrel is fixed to have cup jointed second excitation coil, the inboard fixed mounting of second barrel has second armature, fixedly connected with separates the magnetism post between first armature and the second armature, the hydrovalve includes the valve shell, the valve shell with magnetism shell bottom fixed connection, the inboard of valve shell is provided with control piston along the axial, control piston's upper end is fixed to be inlayed and is equipped with the push rod, the top of push rod with the lower extreme fixed connection of second armature, the spring holding tank has been seted up to the lower terminal surface of control piston, the inboard fixedly connected with reset spring of spring holding tank, reset spring's bottom with the inboard bottom of valve shell is contradicted, the top fixedly connected with buffer beam of first armature, the top fixedly connected with contact plate of buffer beam, the contact plate with fixedly connected with buffer spring between the inboard top of magnetism shell.

As a preferred technical scheme of the present invention, the first cylinder and the second cylinder are both magnetic conductive cylinders and are coaxially disposed, and both ends of the first cylinder and the second cylinder are respectively and fixedly connected with a first magnetic conductive ring and a second magnetic conductive ring.

As a preferable aspect of the present invention, the energizing ends of the first and second exciting coils are electrically connected to a first PWM pulse dc power supply and a second PWM pulse dc power supply, respectively.

As a preferred technical scheme of the invention, the lower end of one side of the valve shell is fixedly provided with a flow sensor, and the signal output end of the flow sensor is connected with a PLC (programmable logic controller).

As a preferable technical solution of the present invention, the center line of the return spring, the center line of the magnetic housing, the center line of the first cylinder, the center line of the second cylinder, and the center line of the control piston are all located on the same straight line.

As a preferred technical scheme of the invention, the working method of the linear servo device of the hydraulic valve comprises the following specific steps:

firstly, the initial position of the hydraulic valve is in a closed state under the action of a return spring; when the hydraulic valve needs to be opened to a preset opening size, the PLC first controls the first PWM pulse direct-current power supply and the second PWM pulse direct-current power supply to respectively output a first PWM and a second PWM pulse which are gradually enhanced from zero, and the average voltage ratio of the first PWM pulse and the second PWM pulse is gradually changed, so that the magnetic force on the first armature and the second armature is unbalanced and overcomes the acting force of a return spring in the valve shell, and a control piston in the hydraulic valve is slowly displaced, slowly opening the hydraulic valve until the opening of the hydraulic valve reaches a preset size, keeping the current average voltage ratio of the first PWM pulse to the second PWM pulse, and enabling the control piston to be in a balance position under the action of the first armature and the second armature at the moment so as to keep the size of the opening of the hydraulic valve unchanged;

when the opening size of the hydraulic valve needs to be adjusted, the PLC gradually adjusts the average voltage ratio of the first PWM pulse and the second PWM pulse, the balance position of the control piston is slowly adjusted under the action of the first armature and the second armature at the moment, the average voltage ratio of the first PWM pulse and the second PWM pulse is stopped changing until the opening of the hydraulic valve reaches the required size, and the control piston stops at the second balance position at the moment;

and thirdly, when the hydraulic valve needs to be closed, correspondingly and gradually adjusting the average voltage ratio of the first PWM pulse to the second PWM pulse by the PLC so that the control piston slowly moves to a closed position under the action of the first armature and the second armature until the hydraulic valve is closed, and stopping outputting the first PWM pulse and the second PWM pulse.

Compared with the prior art, the invention has the beneficial effects that:

the invention is through setting up electromagnetic assembly and hydraulic valve, through PLC programmable controller first control first PWM pulse direct current power supply, second PWM pulse direct current power supply output from zero first PWM and second PWM pulse that strengthen gradually respectively, change the average voltage ratio of first PWM pulse and second PWM pulse gradually at the same time, so as to make the magnetic force on first armature, second armature unbalance and overcome the acting force of the reset spring in the valve outer casing, and make the control piston in the hydraulic valve produce the slow displacement, open the hydraulic valve slowly, until the opening of the hydraulic valve reaches and presets the size, keep the first PWM pulse, second PWM pulse average voltage ratio at present, control the piston to be in the equilibrium position under the first armature and second armature at this moment, make the opening size of the hydraulic valve keep unchanged, the invention controls armature core to replace the direct current proportion of the single coil through adopting multiple coils, the size of the opening can be accurately and slowly controlled, and the condition that the valve core in the hydraulic valve is severely changed in motion state is avoided through the matching of the buffer rod, the contact plate and the buffer spring.

Drawings

FIG. 1 is a schematic diagram of the overall structure of an electromagnetic assembly and hydraulic valve of the present invention;

FIG. 2 is a schematic diagram of a first configuration of the operation of the solenoid assembly and hydraulic valve of the present invention;

FIG. 3 is a schematic diagram of a second configuration of the solenoid assembly and hydraulic valve operation of the present invention.

In the figure: 1. an electromagnetic assembly; 2. a hydraulic valve; 3. a magnetic housing; 4. a first armature; 5. a second armature; 6. a first cylinder; 7. a first excitation coil; 8. a first armature; 9. a second cylinder; 10. a second excitation coil; 11. a second armature; 12. a magnetic isolation column; 13. a valve housing; 14. a control piston; 15. a push rod; 16. a spring receiving groove; 17. a return spring; 18. a buffer rod; 19. a contact plate; 20. a buffer spring; 21. a first magnetically conductive ring; 22. and a second magnetic conductive ring.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-3, the present invention provides a technical solution: a linear servo device of a hydraulic valve and a working method thereof comprise an electromagnetic component 1 and a hydraulic valve 2, wherein the electromagnetic component 1 comprises a magnetic shell 3, the magnetic shell 3 is in a cylindrical shape, the inner side of the magnetic shell 3 is sequentially provided with a first armature 4 and a second armature 5 from top to bottom, the first armature 4 comprises a first barrel 6, the outer side of the first barrel 6 is fixedly sleeved with a first excitation coil 7, the inner side of the first barrel 6 is fixedly provided with a first armature 8, the second armature 5 comprises a second barrel 9, the outer side of the second barrel 9 is fixedly sleeved with a second excitation coil 10, the inner side of the second barrel 9 is fixedly provided with a second armature 11, a magnetism isolating column 12 is fixedly connected between the first armature 8 and the second armature 11, the hydraulic valve 2 comprises a valve shell 13, and the valve shell 13 is fixedly connected with the bottom of the magnetic shell 3, the inboard of valve shell 13 is provided with control piston 14 along the axial, the fixed push rod 15 that is equipped with that inlays in upper end of control piston 14, the top of push rod 15 with the lower extreme fixed connection of second armature 11, spring holding tank 16 has been seted up to the lower terminal surface of control piston 14, the inboard fixedly connected with reset spring 17 of spring holding tank 16, reset spring 17's bottom with contradict at the inboard bottom of valve shell 13, the top fixedly connected with buffer beam 18 of first armature 8, the top fixedly connected with contact plate 19 of buffer beam 18, contact plate 19 with fixedly connected with buffer spring 20 between the inboard top of magnetism shell 3.

In this embodiment, preferably, the first cylinder 6 and the second cylinder 9 are both magnetic conductive cylinders and are coaxially disposed, and both ends of the first cylinder 6 and the second cylinder 9 are fixedly connected with a first magnetic conductive ring 21 and a second magnetic conductive ring 22, respectively.

In this embodiment, preferably, the first and second PWM pulse dc power supplies are electrically connected to the energization ends of the first and

second excitation coils

7 and 10, respectively.

In this embodiment, preferably, a flow sensor is fixedly mounted at a lower end of one side of the valve housing 13, and a signal output end of the flow sensor is connected with a PLC programmable controller.

In this embodiment, preferably, the center line of the return spring 17, the center line of the magnetic housing 3, the center line of the first cylinder 6, the center line of the second cylinder 9, and the center line of the control piston 14 are all located on the same straight line.

In this embodiment, preferably, the working method of the linear servo device of the hydraulic valve includes the following specific steps:

firstly, the initial position of the hydraulic valve 2 is in a closed state under the action of a return spring 17; when the hydraulic valve 2 needs to be opened to a preset opening size, the PLC first controls the first PWM pulse direct-current power supply and the second PWM pulse direct-current power supply to respectively output a first PWM and a second PWM pulse which are gradually enhanced from zero, and the average voltage ratio of the first PWM pulse and the second PWM pulse is gradually changed, so that the magnetic force on the first armature 8 and the second armature 11 is unbalanced and overcomes the acting force of a return spring 17 in the valve shell 13, and a control piston 14 in the hydraulic valve 2 is slowly displaced, slowly opening the hydraulic valve 2 until the opening of the hydraulic valve 2 reaches a preset size, keeping the current average voltage ratio of the first PWM pulse to the second PWM pulse, and enabling the control piston 14 to be in a balance position under the action of the first armature 8 and the second armature 11, so that the size of the opening of the hydraulic valve 2 is kept unchanged;

when the opening size of the hydraulic valve needs to be adjusted, the PLC gradually adjusts the average voltage ratio of the first PWM pulse and the second PWM pulse, the control piston 14 at the moment slowly adjusts the balance position under the action of the first armature 8 and the second armature 11 until the opening of the hydraulic valve 2 reaches the required size, the average voltage ratio of the first PWM pulse and the second PWM pulse is stopped changing, and the control piston 14 at the moment stops at the second balance position;

thirdly, when the hydraulic valve needs to be closed, the PLC correspondingly and gradually adjusts the average voltage ratio of the first PWM pulse to the second PWM pulse so that the control piston 14 slowly moves to the closed position under the action of the first armature 8 and the second armature 11 until the hydraulic valve 2 is closed, and the first PWM pulse and the second PWM pulse are stopped being output.

The working principle and the using process of the invention are as follows: when in use, the hydraulic valve 2 is in a closed state at the initial position under the action of the return spring 17; when the hydraulic valve 2 needs to be opened to a preset opening size, the PLC first controls the first PWM pulse direct current power supply and the second PWM pulse direct current power supply to respectively output a first PWM pulse and a second PWM pulse which are gradually enhanced from zero, and simultaneously gradually changes the average voltage ratio of the first PWM pulse and the second PWM pulse, so that the magnetic force on the first armature 8 and the second armature 11 is unbalanced and overcomes the acting force of a reset spring 17 in a valve shell 13, a control piston 14 in the hydraulic valve 2 slowly displaces to slowly open the hydraulic valve 2 until the opening of the hydraulic valve 2 reaches the preset size, the current average voltage ratio of the first PWM pulse and the second PWM pulse is maintained, and at the moment, the control piston 14 is in a balance position under the action of the first armature and the second armature, so that the size of the opening of the hydraulic valve is kept unchanged; when the opening size of the hydraulic valve needs to be adjusted, the PLC gradually adjusts the average voltage ratio of the first PWM pulse and the second PWM pulse, the control piston 14 at the moment slowly adjusts the balance position under the action of the first armature 8 and the second armature 11 until the opening of the hydraulic valve 2 reaches the required size, the change of the average voltage ratio of the first PWM pulse and the second PWM pulse is stopped, and the control piston 14 at the moment stops at the second balance position; when the hydraulic valve needs to be closed, the PLC correspondingly and gradually adjusts the average voltage ratio of the first PWM pulse to the second PWM pulse so that the control piston 14 slowly moves to the closed position under the action of the first armature 8 and the second armature 11, and the PLC stops outputting the first PWM pulse and the second PWM pulse until the hydraulic valve 2 is closed;

the invention adopts a plurality of coils to control the armature core to replace a single-coil direct-current proportional electromagnet, can accurately and slowly control the size of the opening, and avoids the condition that the valve core in the hydraulic valve is severely changed in motion state through the matching of the buffer rod 18, the contact plate 19 and the buffer spring 20.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The utility model provides a straight line servo of hydrovalve, includes electromagnetic component (1) and hydrovalve (2), its characterized in that: the electromagnetic component (1) comprises a magnetic shell (3), the magnetic shell (3) is cylindrical, the inner side of the magnetic shell (3) is sequentially provided with a first armature (4) and a second armature (5) from top to bottom, the first armature (4) comprises a first barrel (6), the outer side of the first barrel (6) is fixedly sleeved with a first magnet exciting coil (7), the inner side of the first barrel (6) is fixedly provided with a first armature (8), the second armature (5) comprises a second barrel (9), the outer side of the second barrel (9) is fixedly sleeved with a second magnet exciting coil (10), the inner side of the second barrel (9) is fixedly provided with a second armature (11), a magnet isolating column (12) is fixedly connected between the first armature (8) and the second armature (11), the hydraulic valve (2) comprises a valve shell (13), the valve shell (13) is fixedly connected with the bottom of the magnetic shell (3), the inner side of the valve shell (13) is provided with a control piston (14) along the axial direction, a push rod (15) is fixedly embedded at the upper end of the control piston (14), the top of the push rod (15) is fixedly connected with the lower end of the second armature (11), a spring accommodating groove (16) is formed in the lower end face of the control piston (14), a return spring (17) is fixedly connected to the inner side of the spring accommodating groove (16), the bottom end of the reset spring (17) is abutted against the bottom of the inner side of the valve shell (13), the top of the first armature (8) is fixedly connected with a buffer rod (18), the top of the buffer rod (18) is fixedly connected with a contact plate (19), and a buffer spring (20) is fixedly connected between the contact plate (19) and the top of the inner side of the magnetic shell (3).

2. A linear servo device of a hydraulic valve according to claim 1, wherein: first barrel (6) with second barrel (9) are a magnetic conduction section of thick bamboo and coaxial setting, first barrel (6) with the both ends of second barrel (9) are equallyd divide first magnetic conduction ring (21) and second magnetic conduction ring (22) of difference fixedly connected with.

3. A linear servo device of a hydraulic valve according to claim 1, wherein: the energizing ends of the first magnet exciting coil (7) and the second magnet exciting coil (10) are respectively and electrically connected with a first PWM pulse direct current power supply and a second PWM pulse direct current power supply.

4. A linear servo device of a hydraulic valve according to claim 1, wherein: the lower end of one side of the valve shell (13) is fixedly provided with a flow sensor, and the signal output end of the flow sensor is connected with a PLC (programmable logic controller).

5. A linear servo device of a hydraulic valve according to claim 1, wherein: the center line of the reset spring (17), the center line of the magnetic shell (3), the center line of the first cylinder (6), the center line of the second cylinder (9) and the center line of the control piston (14) are all located on the same straight line.

6. The operation method of the linear servo device of a hydraulic valve according to claims 1 to 5, characterized in that: the method comprises the following specific steps:

the initial position of the hydraulic valve (2) is in a closed state under the action of a return spring (17); when the hydraulic valve (2) needs to be opened to a preset opening size, a PLC (programmable logic controller) is used for firstly controlling a first PWM (pulse-width modulation) pulse direct-current power supply and a second PWM pulse direct-current power supply to respectively output a first PWM (pulse-width modulation) pulse and a second PWM pulse which are gradually enhanced from zero, and simultaneously gradually changing the average voltage ratio of the first PWM pulse and the second PWM pulse so as to unbalance the magnetic force on the first armature (8) and the second armature (11), overcome the acting force of a reset spring (17) in the valve shell (13), and enable a control piston (14) in the hydraulic valve (2) to slowly move so as to slowly open the hydraulic valve (2) until the opening of the hydraulic valve (2) reaches the preset size, the current average voltage ratio of the first PWM pulse and the second PWM pulse is maintained, and at the moment, the control piston (14) is in a balance position under the action of the first armature (8) and the second armature (11), keeping the opening size of the hydraulic valve (2) unchanged;

when the opening size of the hydraulic valve needs to be adjusted, the PLC gradually adjusts the average voltage ratio of the first PWM pulse and the second PWM pulse, the control piston (14) slowly adjusts the balance position under the action of the first armature (8) and the second armature (11) at the moment, the average voltage ratio of the first PWM pulse and the second PWM pulse is stopped changing when the opening of the hydraulic valve (2) reaches the required size, and the control piston (14) stops at the second balance position at the moment;

and thirdly, when the hydraulic valve needs to be closed, correspondingly and gradually adjusting the average voltage ratio of the first PWM pulse to the second PWM pulse by the PLC so that the control piston (14) slowly moves to a closed position under the action of the first armature (8) and the second armature (11) until the hydraulic valve (2) is closed, and stopping outputting the first PWM pulse and the second PWM pulse.