WO2020093869A1

WO2020093869A1 - Water base proportional valve and control method thereof

Info

Publication number: WO2020093869A1
Application number: PCT/CN2019/112708
Authority: WO
Inventors: 廖瑶瑶; 柴玮锋; 廉自生; 董建麟; 刘可; 李成
Original assignee: 太原理工大学
Priority date: 2018-11-09
Filing date: 2019-10-23
Publication date: 2020-05-14
Also published as: CN109555740B; CN109555740A

Abstract

A water base proportional valve for a hydraulic support electrohydraulic control system. The water base proportional valve comprises a water base proportional valve structure and a testing control portion; the water base proportional valve structure comprises a main valve liquid inlet valve sleeve (1), a main valve spring (2), a main valve seat (3), a main valve liquid return valve core (4), a main valve liquid inlet valve core (5), a main valve sleeve (21), a main valve liquid return valve sleeve (11), a one-way valve (22), a two-position and two-way electromagnetic switch valve (23), a pilot valve liquid inlet valve core spring (6), a pilot valve liquid inlet valve core spring seat (7), a pilot valve liquid inlet ball valve (8), a pilot valve liquid inlet valve seat (9), a pilot valve liquid return valve core spring (19), a pilot valve liquid return valve core (20), an ejector rod (10), an L-shaped driving rod (12), a lead screw and nut mechanism (13), and a direct current servo motor (15). A method for controlling the water base proportional valve for a hydraulic support electrohydraulic control system. Underground coal mine hydraulic support precise posture adjustment and hydraulic impact reduction are achieved.

Description

Water-based proportional valve and control method thereof

Technical field

The invention relates to a proportional valve used in a hydraulic support electro-hydraulic control system, in particular to a water-based proportional valve and its control method.

Background technique

The hydraulic support is the key supporting equipment for the fully mechanized coal mining face. At present, it completely relies on the operation of the switch-type electro-hydraulic directional valve for lifting, lowering, pushing, and moving. Due to the large support inertia and the support itself, the switch-type electro-hydraulic replacement When the directional valve changes direction quickly, the sudden flow change will cause huge hydraulic shock, cause equipment and pipeline vibration, generate noise, and even cause damage to hydraulic components and systems, seriously affecting production. As the thickness of the coal seam becomes higher and the flow rate of the system increases, this hydraulic shock problem becomes more and more prominent. In addition, in order to ensure the support effect, it is often necessary to adjust the attitude of the hydraulic support. The required flow rate is extremely small, but the flow of the switch-type electro-hydraulic directional valve is large and uncontrollable when it is started, and it cannot guarantee the accurate adjustment of the support posture. Therefore, there is an urgent need for an electro-hydraulic proportional valve that can be applied to hydraulic supports and can adjust the flow rate. The flow rate is adjusted by controlling the opening and closing process of the valve core, and the purpose of reducing hydraulic shock is achieved. First of all, the current proportional valves mostly use proportional electromagnets as electro-mechanical converters to drive the spool. However, due to the contradictory relationship between the proportional electromagnet force and the stroke, it is difficult to perform large flow (large stroke) proportional control. Secondly, most of the current proportional valves use oil as the medium, but the coal mines have high requirements on environmental protection and safety. The use of emulsion or water as the transmission medium in the fully mechanized mining face will inevitably make the water-based proportional valve structural, sealed, and controlled. Characteristics and other aspects are different from the traditional oil valve. Therefore, the present invention proposes a large-flow water-based proportional valve and its control method to solve the problem of precisely adjusting the posture of the hydraulic support under the coal mine and reducing the hydraulic shock.

Summary of the invention

In order to solve the above problems, the present invention provides a water-based proportional valve and its control method.

The present invention adopts the following technical solutions: a water-based proportional valve, including a water-based proportional valve structure and a test control part, the water-based proportional valve structure includes a main valve inlet valve sleeve, a main valve spring, a main valve seat, a main valve return Liquid spool, main valve inlet spool, main valve sleeve, main valve return valve sleeve, pilot valve inlet spool spring, pilot valve inlet spool spring seat, pilot valve inlet ball valve, pilot valve inlet valve Seat, pilot valve return spool spring, pilot valve return spool, check valve, two-position two-way solenoid switch valve, ejector rod, L-shaped drive rod, screw nut mechanism and DC servo motor.

Further, a main valve inlet valve sleeve is installed on the main valve seat, a main valve spring is arranged between the main valve inlet valve sleeve and the main valve seat, the main valve inlet valve core and the main valve seat rely on a plane seal , The main valve inlet valve core is provided with a triangular throttle window, the main valve inlet valve core is arranged in the main valve sleeve, and forms a main valve control cavity with the main valve sleeve, the main valve sleeve and the main valve return valve sleeve pass Screw connection, and form a return cavity with the main valve return valve sleeve, the main valve return valve sleeve is provided with a hole e communicating with the return cavity, the hole e communicates with the return port O; the main valve sleeve is provided with the main valve The hole f communicating with the control chamber is also provided with a hole g that communicates with the left end of the main valve return spool. A check valve and a two-position two-way electromagnetic switch valve are sequentially connected between the hole f and the return port O, and the hole g Connect to the outlet of the check valve. The combined use of one-way valve and two-position two-way electromagnetic switch valve can make the return valve core of the main valve always be in the sealed state to the right during the return process of the proportional valve. If f and g are directly connected, it will cause the high and low pressure of the proportional valve. Short circuit (that is, the P port and the O port are connected) cannot work.

Further, the pilot valve inlet ball valve, the pilot valve inlet spool spring seat, and the pilot valve inlet spool spring are installed in the pilot valve inlet valve seat in order from left to right, forming a whole, which is concentrically installed to the main The valve inlet spool; the right end of the ejector rod is inserted into the inlet valve seat of the pilot valve, and there is a single gap between the ejector rod and the inlet valve seat of the pilot valve; the left end of the ejector rod is connected to the L-shaped drive rod by threads The L-shaped drive rod is installed on the main valve return valve sleeve, the L-shaped drive rod passes through the main valve return valve sleeve and forms a dynamic seal pair, and the left end of the L-shaped drive rod is connected to the screw nut mechanism through threads, The screw nut mechanism is driven by a DC servo motor; the L-shaped drive rod is provided with a through groove, the left side of the pilot valve return valve core is provided with a shoulder, and the shoulder is installed in the groove of the L-shaped drive rod Inside, the pilot valve return spool is limited by the groove. The right side of the pilot valve return spool is installed in the main valve sleeve and forms a sliding seal with it. The rightmost end of the pilot valve return spool is provided with a tapered surface Structure or spherical structure, cone structure or spherical structure and main valve inlet spool The groove edge on the end surface forms a line seal. The pilot valve return valve core has a central hole for the liquid in the main valve control chamber to pass through, and then returns to the return port O through the hole e on the main valve return valve sleeve A pilot valve return valve core spring is installed between the main valve return valve sleeve and the left shoulder of the pilot valve return valve core; the left end of the main valve inlet valve core is provided with an annular groove b, the main valve sleeve There is a small hole a on the top, and the annular groove b communicates with the small hole a, and when the main valve inlet spool moves within the full range of left and right strokes, the annular groove b can completely cover the position of the small hole a.

Further, the test control part includes a speed sensor, an amplifier, a controller and a pressure sensor, a speed sensor is provided between the DC servo motor and the screw nut mechanism, the pressure sensor is provided at the outlet A of the proportional valve, and the pressure sensor is connected to the controller, The controller is connected to the amplifier, and the amplifier is connected to the DC servo motor.

Further, the unilateral gap between the ejector rod and the inlet valve seat of the pilot valve is 1 mm.

A test control method for a water-based proportional valve. The speed sensor detects the speed of the output shaft of the DC servo motor, and the output displacement is obtained by integrating the speed. The active control of the speed of the servo motor is realized by the controller to control the proportional valve. The position of the core is provided with a pressure sensor at the outlet A of the proportional valve. When the flow fluctuation caused by the pressure fluctuation of the load port A is determined by the formula

It can be seen that when the load pressure P _A fluctuates, if the position flow rate is to be constant, the flow rate _A can be adjusted by adjusting the position of the spool to maintain the flow rate. Therefore, the pressure P _{A of the} load port A is detected by the pressure sensor, by adjusting the ratio control valve spool position, the flow rate is maintained constant when the load pressure P _A fluctuation.

Compared with the prior art, the present invention has the following beneficial effects:

(1) The pilot inlet valve and pilot return valve are integrated into the main valve inlet spool, which not only can form a position following system, but also reduce the volume and save the downhole space.

(2) The traditional electro-hydraulic proportional valve is driven by a proportional electromagnet. The proportional electromagnet generates severe heat during the holding phase, and the control stroke is short and the control flow is small. The invention adopts a DC servo motor and a screw nut mechanism, and the holding stage is completed by the screw nut mechanism self-locking, and there is no need to supply power to the DC servo motor. This stage can save more than 50% of energy. Moreover, the invention forms a position following system, the control stroke is not affected, and the control flow range is large.

(3) The present invention can not only actively control the position / speed of the spool in the opening and closing phase, but also passively control the load pressure interference in the holding phase, that is, the position / pressure dual feedback controls the flow rate and reduces the hydraulic shock.

(4) In the present invention, water-based fluid is used as the transmission medium, and it can also be replaced by pure water medium transmission, which is convenient for realizing pollution-free production underground.

BRIEF DESCRIPTION

Figure 1 is a structural diagram of the present invention;

Among them: 1-main valve inlet valve sleeve, 2-main valve spring, 3-main valve seat, 4-main valve return spool, 5-main valve inlet spool, 6-pilot valve inlet spool Spring, 7-Pilot Valve Inlet Spool Spring Seat, 8-Pilot Valve Inlet Ball Valve, 9-Pilot Valve Inlet Valve Seat, 10-Push Rod, 11-Main Valve Return Valve Sleeve, 12-L Drive Rod , 13-screw nut mechanism, 14-speed sensor, 15-DC servo motor, 16-amplifier, 17-controller, 18-pressure sensor, 19-pilot valve return spool spring, 20-pilot valve return valve Core, 21-main valve sleeve, 22-one-way valve, 23-two-position two-way solenoid switch valve, P-inlet, O-return port, A-work port.

detailed description

The specific embodiments of the present invention are further described below with reference to the drawings.

As shown in FIG. 1, a water-based proportional valve includes a water-based proportional valve structure and a test control part. The water-based proportional valve structure includes a main valve inlet valve sleeve 1, a main valve spring 2, a main valve seat 3, a main valve Valve return spool 4, main valve inlet spool 5, main valve sleeve 21, main valve return valve sleeve 11, check valve 22, two-position two-way solenoid switch valve 23, pilot valve inlet spool spring 6 , Pilot valve inlet spool spring seat 7, pilot valve inlet ball valve 8, pilot valve inlet valve seat 9, pilot valve return spool spring 19, pilot valve return spool 20, ejector rod 10, L-shaped drive Rod 12, screw nut mechanism 13 and DC servo motor 15.

A main valve inlet valve sleeve 1 is installed on the main valve seat 3, a main valve spring 2 is arranged between the main valve inlet valve sleeve 1 and the main valve seat 3, the main valve inlet valve core 5 and the main valve The valve seat 3 relies on plane sealing. The main valve inlet spool 5 is provided with a triangular throttle window. The main valve inlet spool 5 is arranged in the main valve sleeve 21 and forms the main valve control cavity with the main valve sleeve 21. The valve sleeve 21 and the main valve return valve sleeve 11 are connected by a thread, and a return cavity is formed between the two. The main valve return valve sleeve 11 is provided with a hole e communicating with the return cavity, and the hole e is in communication with the return port O The main valve sleeve 21 is provided with a hole f communicating with the main valve control chamber, and a channel g communicating with the left end of the main valve return spool 4 is provided, and a one-way valve 22 is sequentially connected between the hole f and the return port O And two-position two-way electromagnetic switch valve 23, and the channel g is connected to the right end outlet of the check valve 22 (also the inlet of the two-position two-way electromagnetic switch valve 23).

The pilot valve inlet ball valve 8, the pilot valve inlet spool spring seat 7, the pilot valve inlet spool spring 6 are installed in the pilot valve inlet valve seat 9 from left to right, forming a whole, which is concentric Installed into the main valve inlet spool 5; the right end of the ejector rod 10 is inserted into the inlet valve seat 9 of the pilot valve, and there is a single gap between the ejector rod 10 and the inlet valve seat 9 of the pilot valve; The left end is connected to the L-shaped drive rod 12 by means of threads. The L-shaped drive rod 12 is installed on the main valve return valve sleeve 11. The L-shaped drive rod 12 passes through the main valve return valve sleeve 11 and forms a dynamic seal pair therewith. The left end of the L-shaped drive rod 12 is connected to the screw nut mechanism 13 through threads, and the screw nut mechanism 13 is driven by the DC servo motor 15; the L-shaped drive rod 12 is provided with a through groove, and the pilot valve returns the spool 20 There is a shoulder on the left side, and the shoulder is installed in the groove of the L-shaped driving rod 12, the groove restricts the pilot valve return spool 20, and the right side of the pilot valve return spool 20 is installed on the main A sliding seal pair is formed in the valve sleeve 21, and the rightmost end of the pilot valve return spool 20 is provided with a tapered surface structure or a spherical structure. The spherical structure forms a line seal with the groove edge on the left end surface of the main valve inlet spool 5, and the pilot valve return spool 20 has a central hole for the passage of the liquid in the main valve control chamber, and then returns the liquid through the main valve The hole e on the valve sleeve 11 returns to the return port O; the pilot valve return valve spool spring 19 is installed between the main valve return valve sleeve 11 and the left shoulder of the pilot valve return valve core 20; the main valve The left end of the inlet valve core 5 is provided with an annular groove b with a groove width of 8.5 mm. The main valve sleeve 21 is provided with a small hole a. The annular groove b communicates with the small hole a, and the main valve inlet valve core 5 is When moving in the full range of left and right, the annular groove b can completely cover the position of the small hole a.

The test control part includes a speed sensor 14, an amplifier 16, a controller 17, and a pressure sensor 18. A speed sensor 14 is provided between the DC servo motor 15 and the screw nut mechanism 13, and the pressure sensor 18 is provided at the outlet A of the proportional valve. The pressure sensor 18 is connected to the controller 17, the controller 17 is connected to the amplifier 16, and the amplifier 16 is connected to the DC servo motor 15.

The working principle and characteristics of the water-based proportional valve: during the opening process, the DC servo motor 15 serves as an electro-mechanical converter to drive the lead screw to rotate, and the nut performs linear movement. Move to the right to open a certain opening, high-pressure liquid enters the main valve control chamber along the annular gap between the inlet valve seat 9 of the pilot valve and the ejector rod 10, and the liquid flows through the hole f and the one-way valve 22 (at this time, the two-position two-way electromagnetic Switch valve 23 is closed), and then through the channel g to the left end of the main valve return spool 4, first push the main valve return spool 4 to the right, close the main spool return port O, and then push the main valve inlet spool 5 To the right, the throttle window of the main valve inlet spool opens until the port of the pilot valve inlet ball valve 8 is closed again. The screw nut 13 keeps moving to the right, the main valve inlet spool 5 keeps moving to the right, how much the jack 10 and the pilot valve inlet ball valve 8 move to the right, the main valve inlet spool 5 will follow to the right How much distance to move, but the movement of the main spool 5 lags behind the pilot valve inlet ball valve 8, so that asynchronous follow-up is achieved. During the opening process, the right end cone surface of the pilot valve return spool 20 is always close to the groove of the left end surface of the main valve inlet spool 5 under the action of the spring force of the pilot valve return spool spring 19, so that the pilot valve returns liquid The valve port is always closed, so that the pilot valve return spool 20 follows the movement of the main valve inlet spool 5 synchronously.

During the closing process, the DC servo motor 15 drives the screw nut 13 and the L-shaped drive rod 12 to move to the left, the pilot valve return spool 20 and the ejector rod 10 move left synchronously under the action of the L-shaped drive rod 12, and the pilot valve returns The right end cone surface of the liquid spool 20 is separated from the groove on the left end surface of the main valve inlet spool 5, the pilot valve return valve port is opened, the main valve control chamber liquid communicates with the return port O, and the main valve inlet valve core 5 moves to the left. Until the groove edge of the left end face of the main valve inlet spool 5 closely abuts the conical surface of the right end of the pilot valve return spool 20, the process is repeated continuously. In this way, during the closing process, the main valve inlet spool 5 asynchronously follows the pilot valve back The liquid spool 20 moves to the left, and the pilot valve inlet ball valve 8 always moves to the left in synchronization with the pilot valve inlet valve seat 9 and the main valve inlet valve spool 5.

During the opening process, the pilot valve inlet ball valve 8 and the main valve inlet spool 5 form an interstage mechanical feedback. During the closing process, the pilot valve return spool 20 and the main valve inlet spool 5 form an interstage Mechanical feedback. The pressure sensor 18 feeds back the load pressure to compensate the flow change caused by the load change.

A test control method for a water-based proportional valve. The rotation speed sensor 14 detects the rotation speed of the output shaft of the DC servo motor 15 and the output displacement is obtained by integrating the rotation speed. The controller 17 realizes active control of the rotation speed of the servo motor 15, thereby To control the position of the proportional valve spool, a pressure sensor 18 is provided at the outlet A of the proportional valve. When the pressure fluctuation of the load port A causes the flow rate change, the formula

Found that, when the load fluctuation of the pressure P _A, to position flow constant, by adjusting the position of the valve body thereby adjusting the size of the through flow area to maintain the flow rate constant A, therefore, by the pressure sensor 18 detects a load port A P _A by adjusting the ratio control valve spool position, the flow rate is maintained constant when the load pressure P _A fluctuation.

Claims

A water-based proportional valve is characterized by comprising a water-based proportional valve structure and a test control part. The water-based proportional valve structure includes a main valve inlet valve sleeve (1), a main valve spring (2), and a main valve seat ( 3), main valve return spool (4), main valve inlet spool (5), main valve sleeve (21), main valve return valve sleeve (11), check valve (22), two-position two Solenoid valve (23), pilot valve inlet valve core spring (6), pilot valve inlet valve core spring seat (7), pilot valve inlet ball valve (8), pilot valve inlet valve seat (9), Pilot valve return valve core spring (19), pilot valve return valve core (20), ejector rod (10), type drive rod (12), screw nut mechanism (13) and DC servo motor (15);

A main valve inlet valve sleeve (1) is installed on the main valve seat (3), and a main valve spring (2) is provided between the main valve inlet valve sleeve (1) and the main valve valve seat (3), The main valve inlet spool (5) and the main valve seat (3) rely on the plane seal, the main valve inlet spool (5) is provided with a triangular throttle window, and the main valve inlet spool (5) is arranged on the main Inside the valve sleeve (21) and form the main valve control cavity with the main valve sleeve (21), the main valve sleeve (21) and the main valve return valve sleeve (11) are connected by a thread, and are connected with the main valve return valve sleeve ( 11) A return cavity is formed, and the main valve return valve sleeve (11) is provided with a hole e communicating with the return cavity, and the hole e is in communication with the return port O;

The main valve sleeve (21) is provided with a hole f communicating with the main valve control chamber, and a hole g communicating with the left end of the main valve return spool (4). The holes f and the return port O are connected in sequence. Check valve (22) and 2 / 2-way solenoid switch valve (23), and the channel g is connected to the outlet of the check valve (22);

The pilot valve inlet ball valve (8), the pilot valve inlet valve core spring seat (7), and the pilot valve inlet valve core spring (6) are installed in the pilot valve inlet valve seat (9) from left to right , Forming a whole, this whole is concentrically installed into the main valve inlet spool (5); the right end of the ejector rod (10) is inserted into the pilot valve inlet valve seat (9), and the ejector rod (10) and the pilot valve There is a single gap between the inlet valve seat (9); the left end of the top rod (10) is connected to the L-shaped drive rod (12) by means of threads, and the L-shaped drive rod (12) is installed in the main valve return valve sleeve (11) On the top, the L-shaped drive rod (12) passes through the main valve return valve sleeve (11) and forms a dynamic seal pair therewith, and the left end of the L-shaped drive rod (12) is connected to the screw nut mechanism (13) through threads, The screw nut mechanism (13) is driven by a DC servo motor (15); the L-shaped drive rod (12) is provided with a through groove, and the left side of the pilot valve return valve core (20) is provided with a shoulder, And the shoulder is installed in the groove of the L-shaped driving rod (12), and the groove restricts the pilot valve return spool (20), and the right side of the pilot valve return spool (20) is installed in the main valve sleeve (21) and form a sliding seal pair with it, the right side of the pilot valve return spool (20) It is provided with a cone-shaped structure or a spherical structure. The cone-shaped structure or the spherical structure forms a line seal with the groove edge of the left end surface of the main valve inlet spool (5), and the pilot valve return spool (20) is opened for the main The central hole in the valve control chamber through which the liquid can pass, and then returns to the return port O through the hole e on the main valve return valve sleeve (11); the main valve return valve sleeve (11) and the pilot valve return valve core ( 20) A pilot valve return spool spring (19) is installed between the left shoulders; the left end of the main valve inlet spool (5) is provided with an annular groove b, and the main valve sleeve (21) is provided with The small hole a, the annular groove b communicates with the small hole a, and when the main valve inlet spool (5) moves within the full range of left and right, the annular groove b can completely cover the position of the small hole a;

The test control part includes a rotation speed sensor (14), an amplifier (16), a controller (17) and a pressure sensor (18), and a rotation speed sensor (15) is provided between the DC servo motor (15) and the screw nut mechanism (13) 14), the pressure sensor (18) is set at the outlet A of the proportional valve, the pressure sensor (18) is connected to the controller (17), the controller (17) is connected to the amplifier (16), and the amplifier (16) is connected to the DC servo motor ( 15) Connect.
The water-based proportional valve according to claim 1, characterized in that the unilateral gap between the ejector rod (10) and the inlet valve seat (9) of the pilot valve is 1 mm.
The water-based proportional valve according to claim 1, wherein the width of the annular groove b is 8.5 mm.
A test control method for a water-based proportional valve according to claim 1 or 2 or 3, characterized in that: the rotational speed sensor (14) detects the rotational speed of the output shaft of the DC servo motor (15), and the integral of the rotational speed can be obtained The output displacement is controlled by the controller (17) to actively control the speed of the servo motor (15), thereby controlling the position of the proportional valve spool. A pressure sensor (18) is provided at the outlet A of the proportional valve, when the load port A When the pressure fluctuation causes the flow rate to change, the formula
Found that, when the load fluctuation of the pressure P A, to position flow constant, by adjusting the position of the valve body thereby adjusting the size of the through flow area to maintain the flow rate constant A, therefore, by the pressure sensor (18) detecting a load pressure port A P A, by adjusting the ratio control valve spool position, the flow rate is maintained constant when the load pressure P A fluctuation.