A sea-depth adaptive water hydraulic flat-type servo valve

Abstract

The present invention discloses a sea-depth adaptive water hydraulic flat-type servo valve, belonging to the technical field related to servo valves. It includes: a pilot mechanism, a valve body mechanism and a displacement sensor mechanism; both ends of the spool in the valve body mechanism are cylinders, the middle part is a cuboid, and a rectangular hollow groove is opened in the middle part, which is in clearance fit with the valve sleeve; the front end face of the flat valve is provided with a rectangular flow channel groove and a round hole for communicating with the flow port of the front end cover, and the front end face of the flat valve is attached to the rear end face of the front end cover; a disc spring is installed between the rear end face of the pressing cylinder and the rear end cover, and the disc spring is in close contact with both of them. The disc spring and the pressing cylinder form a pre-pressure, so that the front end face of the flat valve is closely attached to the rear end face of the front end cover, compensating for the gap between the two and realizing the reliable sealing of the flat valve. The pilot high-speed switching valve adopts a wet compensation structure and is connected to an external balancer through an oil filling interface to realize that the internal pressure of the high-speed switching valve changes together with the external environmental pressure.

Description

Technical Field

[0001] The present invention belongs to the field of servo valves, and more specifically, relates to a deep-sea adaptive water hydraulic flat servo valve. Background Art

[0002] As the core component of an electro-hydraulic servo control system, the electro-hydraulic servo valve has the characteristics of small volume, light weight, high control precision, and fast response speed. It mainly amplifies the input electrical signal through a controller and converts it into the flow or pressure output of the valve, realizing the amplification of the power stage, and controlling the actuator to achieve precise movement.

[0003] Currently, the electro-hydraulic servo valves working underwater are mainly oil pressure servo valves. Since oil leakage is inevitable in oil pressure servo valves, it will cause pollution and damage to the marine ecosystem. While the working medium of water pressure servo valves is water, which has almost no impact on the environment. However, there are still technical difficulties in the research and development of electro-hydraulic servo valves under great sea depths.

[0004] Nozzle flapper servo valves and jet pipe servo valves are currently widely used electro-hydraulic servo valves. Their pilot-stage nozzle flapper valves and jet pipe valves have high control precision but poor anti-pollution ability. The power-stage spool valve has a simple structure. The spool mainly seals through the clearance fit between the valve sleeve and the spool, and reliable sealing cannot be achieved. Moreover, when its working medium is seawater, since the viscosity of seawater is lower than that of oil, this will inevitably aggravate the leakage of the spool, thereby reducing the working reliability of the servo valve.

[0005] High-speed on-off valves have the advantages of fast response speed, high reliability, and strong anti-pollution ability, so they are widely used as the pilot stage of the main valve. In order to further expand the working field of high-speed on-off valves, how to achieve the pressure adaptive compensation function in the deep-sea environment while keeping their volume and mass unchanged is also the focus of current research. Summary of the Invention

[0006] Aiming at the above-mentioned defects or improvement requirements of the prior art, the present invention provides a deep-sea adaptive water hydraulic flat servo valve, aiming to achieve precise control of flow / pressure of the servo valve with seawater as the medium at any sea depth.

[0007] To achieve the above object, according to one aspect of the present invention, a deep-sea adaptive water hydraulic flat servo valve is provided, including: a pilot mechanism, a valve body mechanism, and a displacement sensor mechanism;

[0008] The pilot mechanism includes a pilot housing, an oil filling interface I, and left and right high-speed switching valves; the left and right high-speed switching valves are respectively installed at the left and right ends of the housing, and the oil filling interface I is connected to the left and right high-speed switching valves through flow channels for injecting external oil into the upper ends of the left and right high-speed switching valves respectively, so that the internal pressure of the pilot mechanism is consistent with the external ambient pressure; the lower end face of the pilot housing is provided with first to third through-flow ports, and the front end face is provided with a fourth through-flow port;

[0009] The valve body mechanism includes a valve body and a front end cover, a rear end cover, a left end cover and a right end cover respectively connected to the front, rear, left and right end faces of the valve body; the valve core is placed inside the valve body, and a hollow groove is provided in the middle part of the valve core for placing the flat valve. Flow channels I, II, III and return ports respectively communicating with the flow channels II and III are provided on the front end face of the flat valve; through-flow ports I, II, III, IV are provided on the rear end face of the front end cover. The left and right ends of the valve core are respectively connected to the left end cover and the right end cover through left and right return springs, and cavities I and II are respectively formed between the two ends of the valve core and the left and right end faces of the valve body; fifth to seventh through-flow ports are provided on the upper end face of the valve body;

[0010] The fourth through-flow port communicates with the liquid inlet of the left high-speed switching valve and the first through-flow port through a first flow channel, and communicates with the liquid inlet of the right high-speed switching valve and the second through-flow port through a second flow channel; the first and second flow channels are respectively communicated with cavities I and II;

[0011] When the left and right high-speed switching valves work, their liquid inlets are opened. After part of the liquid in the first and second flow channels respectively passes through the liquid inlets of the left and right high-speed switching valves, it flows out from the liquid outlet, enters the third flow channel, and then passes through the third through-flow port and the seventh through-flow port in sequence to enter the flow channel communicated with the third flow channel, and flows out of the valve body through the through-flow port IV;

[0012] When the opening time of the left high-speed switching valve is earlier than that of the right high-speed switching valve or the duty ratio of the left high-speed switching valve is higher than that of the right high-speed switching valve, the pressure in cavity I is less than the pressure in cavity II. Under the action of the pressure difference, the valve core drives the flat valve to move leftward, so that flow channel I communicates with through-flow port III, and flow channel II communicates with through-flow port II; on the contrary, the valve core drives the flat valve to move rightward, so that flow channel I communicates with through-flow port II, and flow channel III communicates with through-flow port III;

[0013] The displacement sensor mechanism includes an external housing, a displacement sensor and an oil filling interface II. The detection rod of the displacement sensor is installed at the right end of the valve core by means of threaded connection; the oil filling interface II is used for injecting external oil into the external housing so that the internal pressure of the displacement sensor mechanism is consistent with the external ambient pressure.

[0014] Preferably, a groove is formed on the rear end face of the rear end cover for installing a disc spring.

[0015] The front end face of the flat valve is in close contact with the rear end face of the front end cover, the rear end face of the flat valve is in close contact with the front end face of the pressing cylinder, and the disc spring is in close contact with the rear end face of the pressing cylinder, so as to form a dynamic seal between the front end cover and the flat valve and a dynamic seal between the rear end cover and the flat valve.

[0016] Preferably, the displacement sensor detects the displacement signal of the spool, converts it into an electrical signal and feeds it back to the control circuit. The control circuit adjusts the duty cycles of the left and right high-speed switching valves, so that the displacement of the spool continuously approaches the target displacement value.

[0017] Preferably, both the left and right ends of the spool are cylinders, and the two cylinders are radially axisymmetric about the center of the spool; the middle of the spool is a cuboid, and the hollow groove is a rectangular hollow groove.

[0018] Preferably, the compression amount of the left return spring or the right return spring is greater than the displacement amount of the spool; when the servo valve stops working, the spool is under the right return spring to block the connection between the flow channel groove I and the through-flow port III and between the flow channel groove II and the through-flow port IV; or the spool returns to the zero position under the action of the left return spring to block the connection between the flow channel groove I and the through-flow port II and between the flow channel groove III and the through-flow port IV.

[0019] Preferably, a watertight connector I is installed at the front end of the pilot housing for connecting the circuit parts of the left and right high-speed switching valves, and the outer housing is connected to the watertight connector II for connecting the circuit of the displacement sensor.

[0020] Preferably, the flow channel grooves I, II, and III are all rectangular flow channel grooves, and the liquid return port is a circular hole-shaped liquid return port;

[0021] The flow channel groove I is located at the upper end of the flat valve, and the liquid return port is located at the lower end of the flat valve; the flow channel grooves II and III are respectively located at the left and right ends of the flat valve, and have the same structure and size.

[0022] Generally speaking, compared with the prior art by the above technical solutions conceived by the present invention, the following beneficial effects can be obtained:

[0023] 1. Aiming at the problem that the anti-pollution ability of the pilot stage of the existing electro-hydraulic servo valve is poor, the present invention uses a high-speed switching valve with strong anti-pollution ability as the pilot drive, and at the same time can ensure that the response speed of the pilot valve remains unchanged, thereby further improving the working stability of the servo valve.

[0024] 2. Aiming at the problem that existing high-speed on-off valves cannot be exposed to deep-sea environments for operation, the present invention adopts a wet compensation structure. Through an oil filling interface, the oil in the pressure balancer is injected into the electromagnetic part of the high-speed on-off valve, thereby making the pressure inside the high-speed on-off valve the same as the external environmental pressure, and enabling adaptive compensation of the pressure as the working sea depth changes.

[0025] 3. Aiming at the problem of serious leakage when the spool valve of an existing servo valve uses seawater as the medium, the present invention designs a split flat valve and uses the deformation of a disc spring to generate a pre-pressure to achieve a tight fit between the front end face of the flat valve and the flow port end face of the front cover of the main valve body, compensating for the gaps caused by part processing and wear of both end faces, thereby reducing the leakage of the flat valve and achieving its reliable sealing. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic external view of a sea-depth adaptive water hydraulic flat-type servo valve provided by the present invention;

[0027] Figure 2 It is a schematic structural view of a sea-depth adaptive water hydraulic flat-type servo valve provided by the present invention;

[0028] Figure 3 It is a left view of a sea-depth adaptive water hydraulic flat-type servo valve provided by the present invention;

[0029] Figure 4(a) is a schematic structural view of the pilot stage provided by the present invention;

[0030] Figure 4(b) is a top view of the pilot stage provided by the present invention;

[0031] Figure 5 It is a schematic structural view of the front cover provided by the present invention;

[0032] Figure 6 It is a schematic structural view of the spool provided by the present invention;

[0033] Figure 7 It is a schematic structural view of the flat valve provided by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0035] An embodiment of the present invention provides a sea-depth adaptive water hydraulic flat-type servo valve, as Figure 1As shown in the figure, it includes a pilot mechanism, a valve body mechanism, and a displacement sensor mechanism;

[0036] The pilot mechanism includes a pilot housing 17, an oil filling interface I34.1, and left and right high-speed switching valves 18.1 and 18.2. The left and right high-speed switching valves are respectively installed at the left and right ends of the housing 17. The oil filling interface I34.1 is connected to the left and right high-speed switching valves 18.1 and 18.2 through a flow channel 17a, and is used to inject external oil into the upper ends of the left and right high-speed switching valves 18.1 and 18.2 respectively, so that the internal pressure of the pilot mechanism is consistent with the external ambient pressure. The lower end face of the pilot housing 17 is provided with first to third through-flow ports 17A, 17B, and 17T, and the front end face is provided with a fourth through-flow port 17P.

[0037] Specifically, as Figure 2 shown in the figure, the pilot stage is two high-speed switching valves, namely the left and right high-speed switching valves 18.1 and 18.2, which adopt a wet compensation structure. Through the oil filling interface 34.1 at the upper end of the pilot housing 17, external oil is injected into the upper end of the high-speed switching valve 18 through the flow channel 17a. A watertight connector 35.1 is installed at the front end of the pilot housing 17 for connecting the circuit parts of the first high-speed switching valve (i.e., the left high-speed switching valve) 18.1 and the second high-speed switching valve (i.e., the right high-speed switching valve) 18.2.

[0038] The pilot stage mechanism includes: a pilot housing 17, two high-speed switching valves 18.1 and 18.2, a watertight connector 35.1, two gland covers 28.1 and 28.2, and an oil filling interface 34.1. The gland cover 28 is threadedly connected to the pilot housing 17 and installed at the upper end of the pilot housing 17 to play a role in pressing the high-speed switching valve 18 and sealing. The two high-speed switching valves 18.1 and 18.2 adopt a wet compensation structure and are respectively installed at the left and right ends of the pilot housing 17 and are connected through a flow channel 17a. The oil filling interface 34.1 is threadedly connected to the pilot housing 17 and installed at the upper end of the pilot housing 17, and is used to inject external oil into the inside of the pilot housing 17, enter the upper end of the high-speed switching valve 18 through the flow channel 17a, and communicate with an external pressure balancer to ensure that the internal pressures of the high-speed switching valve 18 and the pilot housing 17 are consistent with the external ambient pressure, and realize pressure compensation with the change of the working sea depth; the watertight connector 35.1 is threadedly connected to the pilot housing 17 and installed on the front end face of the pilot housing 17 for connecting the circuit part of the high-speed switching valve 18 and inputting a control signal.

[0039] The valve body mechanism includes a valve body 1 and a front end cover 4, a rear end cover 10, a left end cover 7, and a right end cover 6 respectively connected to the front, rear, left, and right end faces of the valve body. The valve core 2 is placed inside the valve body 1 (as Figure 3As shown, the valve core 2 is nested inside the valve sleeve 15, and the valve sleeve 15 is embedded inside the valve body 1. A hollow groove 2d is opened in the middle part of the valve core 2 for placing the flat valve 3. Flow channel grooves I, II, III 3P, 3A, 3B and return liquid ports 3T respectively communicating with the flow channel grooves II, III are opened on the front end face of the flat valve 3. Through-flow ports I, II, III, IV 4P, 4A, 4B, 4T are opened on the rear end face of the front end cover 4. The left and right ends of the valve core 2 are respectively connected to the left end cover 7 and the right end cover 6 through the left and right return springs 12.1, 12.2. Cavities I, II are formed between the left and right ends of the valve core and the left and right end faces of the valve body respectively. The upper end face of the valve body 1 is provided with the fifth to seventh through-flow ports 1A, 1B, 1T.

[0040] Specifically, four through-flow ports P, A, B, T are opened on the rear end face 4b of the cylindrical step of the front end cover 4 and are fixedly connected to the front end face of the valve body 1.

[0041] A groove 10a is opened on the rear end face of the rear end cover 10 for installing the disc spring 14 and is fixedly connected to the rear end face of the valve body 1.

[0042] The left end cover 7 and the right end cover 6 are respectively fixedly connected to the left and right end faces of the valve body 1.

[0043] Three flow channels are opened on the upper end face of the valve body 1, namely the fifth to seventh through-flow ports 1A, 1B, 1T, which are respectively communicated with the left control cavity (i.e., cavity I), the right control cavity (i.e., cavity II) and the return channel of the valve body 1 through the flow channels.

[0044] The left end 2a of the valve core 2 is a cylinder, the right end 2b is a cylinder, the middle of the valve core 2 is a cuboid 2c and the middle part is a rectangular hollow groove 2d. A clearance fit is formed between the valve core 2 and the valve sleeve 15.

[0045] Four through-flow ports P, A, B, T are opened on the front end face of the flat valve 3, corresponding to the four through-flow ports on the rear end face 4b of the cylindrical step of the front end cover 4. When the valve core is in the middle balance position, the through-flow ports between them are isolated from each other. When the valve core 2 moves to the right, the flat valve 3 also moves to the right with it, and the through-flow port P is communicated with A, and the through-flow port B is communicated with T. When the valve core 2 moves to the left, the flat valve 3 also moves to the left with it, and the through-flow port P is communicated with B, and the through-flow port A is communicated with T. The left return spring 12.1 and the right return spring 12.2 are installed between the left and right ends of the valve core 2 and the left end cover and the right end cover. The compression amount of the return spring 12 is greater than the displacement amount of the valve core 2, so as to ensure that the valve core 2 returns to the zero position.

[0046] A circular groove 10a is opened on the rear surface of the rear end cover 10 for installing the disc spring 14. A clearance fit is formed between the thin cylinder of the rear end cover 10 and the pressing cylinder 5.

[0047] The front end cover 4 forms a dynamic seal with the flat valve 3, and the rear end cover 10 forms a dynamic seal with the flat valve 3.

[0048] The lower end face of the pilot housing 17 is provided with flow ports A, B, and T, which correspond to the flow ports A, B, and T on the upper end face of the valve body 1.

[0049] The fourth flow port 17P communicates with the liquid inlet 18.1P of the left high-speed switching valve and the first flow port 17A through the first flow channel 17e, and communicates with the liquid inlet 18.2P of the right high-speed switching valve and the second flow port 17B through the second flow channel 17d; the first and second flow channels 17e, 17d communicate with the cavities I and II respectively;

[0050] When the left and right high-speed switching valves 18.1, 18.2 are working, their liquid inlets 18.1P, 18.2P are opened. After a part of the liquid in the first and second flow channels 17e, 17d passes through the liquid inlets 18.1P, 18.2P of the left and right high-speed switching valves 18.1, 18.2 respectively, it flows out from the liquid outlets 18.1T, 18.2T, enters the third flow channel 17b, then passes through the third flow port 17T and the seventh flow port 1T in sequence to enter the valve body, and then flows out of the valve body through the flow port IV 4T after passing through the flow channel communicating with the third flow channel.

[0051] Specifically, the lower part of the front end face of the pilot housing 17 is provided with a fourth flow port 17P, which communicates with the liquid inlet of the first high-speed switching valve 18.1 and the first flow port 17A on the lower end face of the pilot housing 17 through the first flow channel 17e, and communicates with the liquid inlet of the right high-speed switching valve 18.2 and the second flow port 17B on the lower end face of the pilot housing 17 through the second flow channel 17d. When the opening time of the first high-speed switching valve 18.1 is less than that of the second high-speed switching valve 18.2, the pressure in the first flow channel 17e where the first flow port 17A on the lower end face of the pilot housing 17 communicates with the flow port on the upper end face of the valve body 1 (i.e., the fifth flow port 1A) is less than the pressure in the second flow channel 17d where the second flow port 17B on the lower end face of the pilot housing 17 communicates with the flow port 1B on the upper end face of the valve body 1; when the opening time of the first high-speed switching valve 18.1 is greater than that of the second high-speed switching valve 18.2, the pressure in the first flow channel 17e where the first flow port 17A on the lower end face of the pilot housing 17 communicates with the flow port on the upper end face of the valve body 1 (i.e., the fifth flow port 1A) is greater than the pressure in the second flow channel 17d where the second flow port 17B on the lower end face of the pilot housing 17 communicates with the flow port 1B on the upper end face of the valve body 1; when the high-speed switching valve 18 is working, a part of the flowing liquid in the first flow channel 17e and the second flow channel 17d will flow out through the liquid outlet of the high-speed switching valve 18 and enter the third flow channel 17b, pass through the third flow port (return port) 17T on the lower end face of the pilot housing 17 and the flow port 1T on the upper end face of the valve body 1 to enter the valve body 1, enter the flow port 4Ta through the flow channel communicating with the third flow channel, and then flow out from the flow port IV 4T through the said flow channel, asFigure 3 As shown. It can be understood that the valve sleeve 15 is provided with a through hole, and the flow channel communicating with the third flow channel penetrates through the through hole.

[0052] When the opening time of the left high-speed switching valve is earlier than that of the right high-speed switching valve or the duty ratio of the left high-speed switching valve is higher than that of the right high-speed switching valve, the pressure in the cavity I is less than the pressure in the cavity II. Under the action of the pressure difference, the valve core 2 drives the flat valve 3 to move leftward, so that the flow channel groove I3P communicates with the through-flow port III4B, and the flow channel groove II3A communicates with the through-flow port II 4A; conversely, the valve core 2 drives the flat valve 3 to move rightward, so that the flow channel groove I3P communicates with the through-flow port II4A, and the flow channel groove III3B communicates with the through-flow port III4B; wherein, regardless of whether the flat valve moves or when the flat valve is in the zero position, the flow channel groove I 3P and the through-flow port I 4P, and the liquid return port 3T and the through-flow port IV 4T always remain in communication;

[0053] The displacement sensor mechanism includes an external housing 37, a displacement sensor 40 and an oil filling interface II34.2. The detection rod of the displacement sensor 40 is installed at the right end of the valve core 2 by means of threaded connection; the oil filling interface II34.2 is used to inject external oil into the external housing 37 so that the internal pressure of the displacement sensor mechanism is consistent with the external environmental pressure.

[0054] Specifically, the displacement sensor 40 is installed on the side surface of the right end cover 6 of the valve body 1. By means of threaded connection, the detection rod of the displacement sensor 40 is installed at the right end of the valve core 2 by means of threaded connection; the displacement sensor 40 is placed in the external housing 37 by means of a wet compensation method.

[0055] The upper end of the external housing 37 is installed with an oil filling interface 34.2 by means of threaded connection; the right end of the external housing 37 is installed with a watertight connector 35.2 by means of threaded connection.

[0056] Preferably, a groove 10a is formed on the rear end surface of the rear end cover 10 for installing the disc spring 14;

[0057] The front end surface of the flat valve 3 is in close contact with the rear end surface of the front end cover 4, the rear end surface of the flat valve 3 is in close contact with the front end surface of the pressing cylinder 5, and the disc spring 14 is in close contact with the rear end surface of the pressing cylinder 5 to form a dynamic seal between the front end cover 4 and the flat valve 3 and a dynamic seal between the rear end cover and the flat valve 3.

[0058] Specifically, the rear end cover 10 is provided with a groove 10a for installing the disc spring 14. The disc spring 14 is in close contact with the rear end face of the pressing cylinder 5. The disc spring 14 will undergo compressive deformation between the two to generate a force. The pre-pressure of the disc spring 14 acts on the flat valve 3 through the pressing cylinder 5, realizing the close fit between the front end face of the flat valve 3 and the rear end face of the front end cover 4, and compensating for the fitting gap between the flat valve 3 and the front end cover 4.

[0059] Preferably, the displacement sensor 40 detects the displacement signal of the valve core 2, converts it into an electrical signal and feeds it back to the control circuit. The control circuit adjusts the duty cycles of the left and right high-speed switching valves 18.1 and 18.2, so that the displacement of the valve core 2 continuously approaches the target displacement value.

[0060] Preferably, both the left and right ends 2a and 2b of the valve core 2 are cylinders, and the two cylinders are radially axisymmetric about the center of the valve core; the middle of the valve core 2 is a cuboid 2c, and the hollow groove is a rectangular hollow groove.

[0061] Specifically, the left end 2a of the valve core 2 is a cylinder, the right end 2b is a cylinder, the two cylinders are radially axisymmetric about the center of the valve core, the middle of the valve core 2 is a cuboid 2c and the middle part thereof is a rectangular hollow groove 2d.

[0062] Preferably, the compression amount of the left return spring or the right return spring is greater than the displacement amount of the valve core 2; when the servo valve stops working, the valve core 2 is under the right return spring to block the communication between the flow channel groove I 3P and the through-flow port III 4B, and between the flow channel groove II 3A and the through-flow port IV 4T; or the valve core 2 returns to the zero position under the action of the left return spring to block the communication between the flow channel groove I 3P and the through-flow port II 4A, and between the flow channel groove III 3B and the through-flow port IV 4T.

[0063] Preferably, a watertight connector I 35.1 is installed at the front end of the pilot housing 17 for connecting the circuit parts of the left and right high-speed switching valves 18.1 and 18.2, and the external housing 37 is connected to the watertight connector II 35.2 for connecting the circuit part of the displacement sensor.

[0064] Preferably, the flow channel grooves I, II, and III are all rectangular flow channel grooves, and the liquid return port 3T is a circular hole-shaped liquid return port;

[0065] The flow channel groove I is located at the upper end of the flat valve 3, and the liquid return port 3T is located at the lower end of the flat valve 3; the flow channel grooves II and III are respectively located at the left and right ends of the flat valve 3, and have the same structure and dimensions.

[0066] Specifically, the flat valve 3 and the rectangular hollow groove 2d of the valve core 2 are in clearance fit. The front end face of the flat valve 3 is provided with three rectangular flow channel grooves and a circular hole for the return liquid port. The first inlet flow rectangular groove (i.e., the flow channel groove I 3P) is located at the upper end of the flat valve 3, the second commutation rectangular groove (i.e., the flow channel groove II 3A) is located at the left end of the flat valve 3, the third commutation rectangular groove (i.e., the flow channel groove III 3B) is located at the right end of the flat valve 3, the return liquid port 3T is located at the lower end of the flat valve 3, and the second commutation rectangular groove 3A and the third commutation rectangular groove 3B have exactly the same structural dimensions.

[0067] Further, as shown in FIGS. 4(a) and 4(b), the upper end face of the pilot housing 17 is provided with a threaded hole for installing the oil filling interface 34.1; a flow channel 17a is provided inside the upper end of the pilot housing 17, which communicates with the upper ends of the first high-speed switching valve 18.1 and the second high-speed switching valve 18.2, so that the oil fills the electromagnetic components of the high-speed switching valves 18.1 and 18.2, that is, the iron core 18a and the coil 18b, thereby making the internal pressure of the pilot mechanism consistent with the external ambient pressure; the lower end of the high-speed switching valve 18 is a wet armature 18d, and this part works in a water environment with a certain pressure; the upper end of the high-speed switching valve 18 is immersed in the oil, and the lower end is immersed in the water. In order to prevent the mutual penetration of the two media, an O-ring 18c is installed at the lower end of the iron core 18a of the high-speed switching valve 18. Through the above design, the pressure compensation of the high-speed switching valve 18 is realized. The upper end of the front end face of the pilot housing 17 is provided with a threaded hole for installing the watertight connector 35.1; the lower end of the front end face of the pilot housing 17 is provided with a threaded hole flow port (i.e., the fourth flow port 17P) for installing the flow port connector to connect to the external pressure source to provide pressure for the pilot stage; the flowing liquid enters the inside of the pilot housing 17 from the flow port 17c. At this time, the left flow channel 17e and the right flow channel 17d are chambers with a certain pressure. When the high-speed switching valve 18 is opened with different duty ratios, the pressures of the left flow channel 17e and the right flow channel 17d will decrease to different degrees, so that a pressure difference appears at both ends of the valve core 2, and it starts to move in a certain direction.

[0068] As Figure 5 shown, the large end of the front end cover 4 is a cuboid, and a cylinder extends from the center of the cuboid. The first flow port (i.e., the flow port I 4P), the first commutation flow port (i.e., the flow port II 4A), the second commutation flow port (i.e., the flow port III 4B), and the first return liquid port (i.e., the flow port IV 4T) are opened on the rear end face 4b of the cylinder. Among them, the first commutation flow port 4A and the second commutation flow port 4B are symmetric about the center of the rear end face 4b; a circular ring groove 4a is opened on the rear end face of the large end of the front end cover 4, and a flow port 4Ta is opened on the surface of the circular ring groove 4a, and its center is on the same straight line as the centers of the first flow port (i.e., the flow port I 4P) and the first return liquid port (i.e., the flow port IV 4T).

[0069] As Figure 6As shown, both the left and right ends 2a, 2b of the spool 2 are cylinders, which form a clearance fit with the valve sleeve 15 and play a certain sealing role; the middle of the spool 2 is a cuboid 2c with a rectangular hollow groove 2d, and the main function of the rectangular hollow groove 2d is to install the flat valve 3.

[0070] As Figure 7 shown, the overall shape of the flat valve 3 is a cuboid, and its front end face is provided with a first inlet rectangular groove (i.e., flow channel groove I 3P), a second commutation rectangular groove (i.e., flow channel groove II 3A), a third commutation rectangular groove (i.e., flow channel groove III 3B) and a liquid return port 3T; the front end face of the flat valve 3 is in contact with the rear end face 4b of the cylinder of the front end cover 4, and the four flow ports between the two correspond; a pressing cylinder 5 is installed on the rear end face of the flat valve 3, and a disc spring 14 is installed between the rear end face of the pressing cylinder 5 and the rear end cover 10. The force generated by the pre-deformation of the disc spring 14 acts on the flat valve 3, so that the front end face of the flat valve 3 closely adheres to the rear end face 4b of the cylinder of the front end cover 4, compensating for the gap between the two and realizing zero leakage of the flat valve.

[0071] The working process of this water hydraulic flat type servo valve is as follows: First, connect the oil filling interface 34.1 to the pressure equalizer, and adjust the inlet oil pressure of the oil filling interface 34.1 in real time according to the change of the working depth of the servo valve to ensure the internal and external pressure balance of the pilot high-speed switch valve 18. When the pilot high-speed switch valve 18 does not act, the servo valve does not work; when the pilot high-speed switch valve 18 starts to work, due to the different opening times of the first high-speed switch valve 18.1 and the second high-speed switch valve 18.2, the pressure in the chamber of the flow channel 17e (i.e., cavity I) is different from the pressure in the chamber of the flow channel 17d (i.e., cavity II), causing the spool 2 to move under the action of the pressure difference. The flow ports corresponding to the front end face of the flat valve 3 and the front end cover 4 start to communicate, and corresponding flow rate / pressure is continuously output; at the same time, the displacement sensor 40 detects the signal of the displacement of the spool 2 and converts it into an electrical signal to feedback to the control circuit part. The control circuit changes the duty ratio of the high-speed switch valve 18 through differential operation, so as to adjust the duty ratio of the high-speed switch valve 18, making the displacement of the spool 2 continuously approach the target displacement value. When the difference between the electrical signal of the displacement of the spool 2 detected by the displacement sensor 40 and the target value is 0, the high-speed switch valve 18 stops working, and the spool 2 maintains working at this position; when the servo valve stops working, the pilot stage no longer supplies pressure, and the spool 2 returns to the zero position under the action of the return spring 12, and the flow ports on the front end face of the flat valve 3 are blocked from the flow ports of the front end cover 4.

[0072] The present invention provides a structure of a pilot high-speed switch valve with a wet compensation function, which can improve the anti-pollution ability of the pilot stage. At the same time, it also provides a flat type spool valve structure with automatic clearance compensation, solving the problem of large leakage of traditional spool valves.

[0073] The structure of the present invention is compact, improving the anti-pollution ability of the pilot valve, enabling the deep-sea pressure self-adaptive compensation function, compensating for the gap between the moving pairs of the flat valve, having reliable sealing performance, and being able to accurately output the corresponding flow rate / pressure.

[0074] It is easy for those skilled in the art to understand that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A sea depth self - adapting water hydraulic flat - type servo valve, characterized in that, Comprising: A pilot mechanism, a valve body mechanism and a displacement sensor mechanism; The pilot mechanism includes a pilot housing (17), an oil filling port I (34.1), and left and right high-speed switching valves (18.1, 18.2); the left and right high-speed switching valves are respectively installed at the left and right ends of the pilot housing (17), and the oil filling port I (34.1) is connected to the left and right high-speed switching valves (18.1, 18.2) respectively through a flow channel (17a) for injecting external oil into the upper ends of the left and right high-speed switching valves (18.1, 18.2) respectively, so that the internal pressure of the pilot mechanism is consistent with the external ambient pressure; the lower end face of the pilot housing (17) is provided with first to third through-flow ports (17A, 17B, 17T), and the front end face is provided with a fourth through-flow port (17P); The valve body mechanism includes a valve body (1) and a front end cover (4), a rear end cover (10), a left end cover (7) and a right end cover (6) respectively connected to the front, rear, left and right end faces of the valve body; a valve core (2) is placed inside the valve body (1), and a hollow groove (2d) is provided in the middle part of the valve core (2) for placing a flat valve (3). The front end face of the flat valve (3) is provided with flow channels I, II, III (3P, 3A, 3B) and return ports (3T) respectively communicating with the flow channels II, III; the rear end face of the front end cover (4) is provided with through-flow ports I, II, III, IV (4P, 4A, 4B, 4T). The left and right ends of the valve core (2) are respectively connected to the left end cover (7) and the right end cover (6) through left and right return springs (12.1, 12.2). Cavities I and II are formed between the two ends of the valve core and the left and right end faces of the valve body respectively; the upper end face of the valve body (1) is provided with fifth to seventh through-flow ports (1A, 1B, 1T); The fourth through-flow port (17P) is connected to the liquid inlet (18.1P) of the left high-speed switching valve and the first through-flow port (17A) through a first flow channel (17e), and is connected to the liquid inlet (18.2P) of the right high-speed switching valve and the second through-flow port (17B) through a second flow channel (17d); the first and second flow channels (17e, 17d) are respectively connected to cavities I and II; When the left and right high-speed switching valves work, their liquid inlets (18.1P, 18.2P) are opened. After part of the liquid in the first and second flow channels (17e, 17d) respectively passes through the liquid inlets (18.1P, 18.2P) of the left and right high-speed switching valves, it flows out from the liquid outlets (18.1T, 18.2T), enters the third flow channel (17b), then passes through the third through-flow port (17T) and the seventh through-flow port (1T) in sequence and enters the flow channel communicating with the third flow channel, and flows out of the valve body through the through-flow port IV (4T); When the opening time of the left high-speed switching valve is earlier than that of the right high-speed switching valve or the duty ratio of the left high-speed switching valve is higher than that of the right high-speed switching valve, the pressure in the cavity I is less than the pressure in the cavity II. Under the action of the pressure difference, the valve core (2) drives the flat valve (3) to move to the left, so that the flow channel groove I (3P) is communicated with the through-flow port III (4B), and the flow channel groove II (3A) is communicated with the through-flow port II (4A); conversely, the valve core (2) drives the flat valve (3) to move to the right, so that the flow channel groove I (3P) is communicated with the through-flow port II (4A), and the flow channel groove III (3B) is communicated with the through-flow port III (4B). The displacement sensor mechanism includes an external housing (37), a displacement sensor (40) and an oil filling interface II (34.2). The detection rod of the displacement sensor (40) is installed at the right end of the valve core (2) by means of threaded connection; the oil filling interface II (34.2) is used to inject external oil into the external housing (37) so that the internal pressure of the displacement sensor mechanism is consistent with the external environmental pressure.

2. The servo valve according to claim 1, characterized in that, A groove (10a) is formed on the rear end face of the rear end cover (10) for installing the disc spring (14). The front end face of the flat valve (3) is in close contact with the rear end face of the front end cover (4), the rear end face of the flat valve (3) is in close contact with the front end face of the pressing cylinder (5), and the disc spring (14) is in close contact with the rear end face of the pressing cylinder (5) to form a dynamic seal between the front end cover (4) and the flat valve (3), and a dynamic seal between the rear end cover (10) and the flat valve (3).

3. The servo valve according to claim 1, wherein The displacement sensor (40) converts the displacement signal of the valve core (2) into an electrical signal and feeds it back to the control circuit. The control circuit adjusts the duty ratios of the left and right high-speed switching valves (18.1, 18.2) so that the displacement of the valve core (2) continuously approaches the target displacement value.

4. The servo valve according to claim 1, characterized in that, The left and right ends (2a, 2b) of the valve core (2) are both cylinders, and the two cylinders are radially axisymmetric about the center of the valve core; the middle of the valve core (2) is a cuboid (2c), and the hollow groove is a rectangular hollow groove.

5. The servo valve according to claim 1, characterized in that, The compression amount of the left return spring or the right return spring is greater than the displacement amount of the valve core (2); when the servo valve stops working, the valve core (2) is in the right return spring, blocking the communication between the flow channel groove I (3P) and the through-flow port III (4B), and the flow channel groove II (3A) and the through-flow port IV (4T); or the valve core (2) returns to the zero position under the action of the left return spring, blocking the communication between the flow channel groove I (3P) and the through-flow port II (4A), and the flow channel groove III (3B) and the through-flow port IV (4T).

6. The servo valve according to claim 1, characterized in that, The front end of the pilot housing (17) is equipped with a watertight connector I (35.1) for connecting the circuit parts of the left and right high-speed switching valves (18.1, 18.2), and the external housing (37) is connected with a watertight connector II (35.2) for connecting the circuit of the displacement sensor.

7. The servo valve according to claim 1, characterized in that, The flow channel grooves I, II, and III are all rectangular flow channel grooves, and the return liquid port (3T) is a circular hole-shaped return liquid port. The flow channel groove I is located at the upper end of the flat valve (3), and the liquid return port (3T) is located at the lower end of the flat valve (3); the flow channel grooves II and III are respectively located at the left end and the right end of the flat valve (3), and have the same structure and dimensions.

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