Electro-hydraulic reversing valve

Abstract

The utility model discloses an electro-hydraulic reversing valve which comprises a first valve body and a gear reversing slide valve assembly installed on the first valve body, and the gear reversing slide valve assembly comprises a reversing valve element, a positioning sleeve and a telescopic positioning piece. A reversing hole is formed in the first valve body and comprises a left hydraulic part, a reversing part and a right hydraulic part, and the two hydraulic parts are communicated through the reversing part; a reverse ring groove, a neutral gear ring groove and an ahead ring groove which are axially arranged are formed in the inner wall of the positioning sleeve; the reversing valve element is installed in the reversing part in a sliding mode. The reversing valve element is sleeved with the positioning sleeve, and the positioning sleeve is fixed in the first valve body. The positioning piece is installed on the gear shifting valve element, and the end of the positioning piece can protrude from the sliding gear valve element and abut against the inner wall of the positioning sleeve. Thus, it can be ensured that the reversing valve can still keep the gear state in the power-off state, then the ship transmission device keeps the original motion state, the ship continues to keep the original sailing state, and safety accidents are avoided.

Description

Technical Field

[0001] The utility model relates to the field of hydraulic control reversing devices, in particular to an electro-hydraulic reversing valve. Background Art

[0002] The ship's transmission device generally has three gears: forward, neutral, and reverse. The gear switching is achieved by electro-hydraulic control. In the event of a sudden power outage or electrical failure, from the perspective of ship safety, the transmission device must maintain the gear state unchanged so that the ship can continue to maintain its original navigation state and avoid safety accidents. Utility Model Content

[0003] In order to solve the problems in the prior art, the utility model aims to provide an electro-hydraulic reversing valve, which can maintain the original gear position after power failure.

[0004] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme: an electro-hydraulic reversing valve, comprising a first valve body and a gear reversing slide valve assembly mounted on the first valve body, the gear reversing slide valve assembly comprising a reversing valve core, a positioning sleeve and a retractable positioning member;

[0005] The first valve body is provided with a reversing hole, which includes a left hydraulic part, a reversing part and a right hydraulic part, and the two hydraulic parts are connected through the reversing part;

[0006] The inner wall of the positioning sleeve is provided with a reverse ring groove, a neutral ring groove and a forward ring groove arranged axially;

[0007] The reversing valve core is slidably installed in the reversing part. By controlling the pressure in the two hydraulic parts, the reversing valve core can be driven to move left and right, so that the end of the reversing valve core can enter and exit the hydraulic part;

[0008] The positioning sleeve is arranged on the reversing valve core, and the positioning sleeve is fixed in the first valve body; the positioning piece is installed on the shift valve core, and the end of the positioning piece can protrude from the sliding valve core and abut against the inner wall of the positioning sleeve.

[0009] Preferably, the positioning member includes a positioning spring and a steel ball. A positioning hole is provided on the reversing valve core. The positioning spring and the steel ball are arranged in the positioning hole. The positioning spring can push the steel ball to protrude from the reversing valve core.

[0010] Preferably, two steel balls are arranged at both ends of the positioning spring; the positioning spring can push the two steel balls to protrude from the reversing valve core and insert into the reverse ring groove, the neutral ring groove or the forward ring groove.

[0011] Preferably, the reverse ring groove, the neutral ring groove and the forward ring groove are V-shaped ring grooves.

[0012] Preferably, the positioning sleeve is fixed in the right hydraulic part.

[0013] Preferably, the gear reversing sliding valve assembly also includes a first left end cover and a first right end cover; the left hydraulic part and the right hydraulic part are arranged at the left and right ends of the first valve body, the left hydraulic part and the right hydraulic part are open, the first left end cover is fixed to the left end of the first valve body and blocks the left hydraulic part, and the first right end cover is fixed to the right end of the first valve body and blocks the right hydraulic part.

[0014] Preferably, a first left sealing gasket is provided between the first left end cover and the first valve body, and a first right sealing gasket is provided between the first right end cover and the first valve body.

[0015] Preferably, the gear reversing slide valve assembly further includes a left positioning piston 2 and a right positioning piston; the left positioning piston 2 is slidably installed in the left hydraulic part, and the right positioning piston is slidably installed in the right hydraulic part.

[0016] Preferably, a P chamber, a K chamber, an A chamber, a B chamber and a T2 oil return port are arranged between the inner wall of the reversing part and the reversing valve core, two K chambers are arranged on the left and right sides of the P chamber, two K chambers are arranged between the A chamber and the B chamber, and the A chamber and the B chamber are located between the two T2 oil return ports; the A chamber is connected to the I gear clutch, and the B chamber is connected to the II gear clutch.

[0017] Preferably, the I-gear clutch is a forward clutch, and the II-gear clutch is a reverse clutch.

[0018] The beneficial effect of the technical solution of the utility model is that it can ensure that the reversing valve can still maintain the gear state when the power is off, so that the ship's transmission device can maintain the original movement state, so that the ship can continue to maintain the original navigation state and avoid the occurrence of safety accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the control principle diagram of the electro-hydraulic reversing valve;

[0020] Figure 2 The structure of the solenoid valve Figure 1 ;

[0021] Figure 3 for Figure 2 Middle, II-direction cross-sectional view;

[0022] Figure 4 for Figure 2 Middle, M-direction view;

[0023] Figure 5 for Figure 4 Middle, EE section view;

[0024] Figure 6 for Figure 2 Middle, NN-direction cross-sectional view;

[0025] Figure 7for Figure 6 Middle, S-direction cross-sectional view;

[0026] Figure 8 The structure of the solenoid valve Figure 2 .

[0027] Reference numerals: 1, pressure regulating valve assembly; 101, second left end cover; 102, throttling screw; 103, second left sealing gasket; 104, small piston; 1041, U chamber; 1042, V chamber; 1043, C chamber; 105, spring group; 106, pressure regulating spacer; 107, large piston; 1071, D chamber; 108, first valve body; 109, second right sealing gasket; 110, second right cover plate; 111, upper cover plate sealing gasket; 112, upper cover plate;

[0028] 2. Shift-shift slide valve assembly; 201. First left end cover; 202. First left sealing gasket; 203. Left positioning piston; 2031. H chamber; 2032. G chamber; 204. Reversing valve core; 2041. Positioning hole; 2042. P chamber; 2043. K chamber; 2044. B chamber; 2045. A chamber; 2046. T2 oil return port; 205. Positioning sleeve; 2051. Reverse ring groove; 2052. Neutral ring groove; 2053. Forward ring groove; 206. Steel ball; 207. Positioning spring; 208. Right positioning piston; 2081. E chamber; 2082. F chamber; 209. First right sealing gasket; 210. First right end cover; 211. Retaining ring;

[0029] 3. Solenoid reversing valve assembly; 301. Reverse solenoid valve; 302. Neutral solenoid valve; 303. Forward solenoid valve; 304. Second valve body; 3041. P oil port; 3042. A1 oil channel; 3043. A2 oil channel; 3044. A3 oil channel; 3045. T1 oil return port. DETAILED DESCRIPTION

[0030] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0031] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0032] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, "plurality" means two or more, unless otherwise clearly defined.

[0033] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0035] The orientation described in the following embodiments is Figure 7 As shown, the position of the C chamber is the front, the position of the reversing valve is the back, the position of the left end plate is the left, the position of the right end plate is the right, and the position of the solenoid valve is the top. Example

[0036] like Figures 1 to 8The electro-hydraulic reversing valve shown includes a first valve body 108 and a gear reversing slide valve assembly 2 mounted on the first valve body 108, wherein the gear reversing slide valve assembly 2 includes a reversing valve core 204, a positioning sleeve 205 and a retractable positioning member;

[0037] The first valve body 108 is provided with a reversing hole, which includes a left hydraulic part, a reversing part and a right hydraulic part, and the two hydraulic parts are connected through the reversing part;

[0038] The inner wall of the positioning sleeve 205 is provided with a reverse gear ring groove 2051, a neutral gear ring groove 2052 and a forward gear ring groove 2053 arranged axially;

[0039] The reversing valve core 204 is slidably installed in the reversing part. By controlling the pressure in the two hydraulic parts, the reversing valve core 204 can be driven to move left and right, so that the end of the reversing valve core 204 can enter and exit the hydraulic part.

[0040] The positioning sleeve 205 is sleeved on the reversing valve core 204 , and the positioning sleeve 205 is fixed in the first valve body 108 ; the positioning member is installed on the shift valve core 204 , and the end of the positioning member can protrude from the shift valve core 204 and abut against the inner wall of the positioning sleeve 205 .

[0041] The through hole of the electro-hydraulic reversing valve controls the pressure of the two hydraulic chambers on the left and right ends of the reversing valve core 204, thereby changing the relative position of the reversing valve core 204 and the positioning sleeve 205, so that the positioning piece cooperates with the reverse ring groove 2051, the neutral ring groove 2052 or the forward ring groove 2053.

[0042] Such a setting can ensure that the reversing valve can still maintain the gear state when the power is off, so that the ship's transmission device can maintain its original movement state, so that the ship can continue to maintain its original navigation state and avoid the occurrence of safety accidents.

[0043] like Figure 6 As shown, in this embodiment, a P chamber 2042, a K chamber 2043, an A chamber 2045, a B chamber 2044 and a T2 oil return port 2046 are arranged between the inner wall of the reversing part and the reversing valve core 204, two K chambers 2043 are arranged on the left and right sides of the P chamber 2042, two K chambers 2043 are arranged between the A chamber 2045 and the B chamber 2044, and the A chamber 2045 and the B chamber 2044 are located between the two T2 oil return ports 2046; the A chamber 2045 is connected to the I gear clutch, and the B chamber 2044 is connected to the II gear clutch; wherein, the I gear clutch is a forward clutch, and the II gear clutch is a reverse clutch.

[0044] By controlling the movement of the reversing valve core 204, the K chamber 2043, the A chamber 2045 and the T2 oil return port 2046 can be connected, the K chamber 2043, the B chamber 2044 and the T2 oil return port 2046 can be connected, or the P chamber 2042, the K chamber 2043 and the A chamber 2045 can be connected, and the P chamber 2042, the K chamber 2043 and the B chamber 2044 can be connected. Such a configuration can effectively ensure the action of the reversing valve core.

[0045] like Figure 6 and Figure 7 As shown, in this embodiment, the positioning member includes a spring 207 and a steel ball 206. A positioning hole 2041 is provided on the reversing valve core 204. The positioning spring 207 is arranged in the positioning hole 2041. Two steel balls 206 are arranged at both ends of the positioning spring 207. The positioning spring 207 can push the steel ball 206 to protrude from the reversing valve core 204. Such a setting can ensure the effectiveness of locking and also make the structure of the invention simpler.

[0046] like Figure 7 As shown, in this embodiment, the reverse gear ring groove 2051, the neutral gear ring groove 2052 and the forward gear ring groove 2053 are V-shaped ring grooves. Such an arrangement can ensure the stability of the positioning sleeve and the steel ball clamping.

[0047] like Figure 6 and Figure 7 As shown, in this embodiment, the positioning sleeve 205 is arranged in the right hydraulic part and is tightly matched. A retaining ring 211 capable of limiting the positioning sleeve in the cavity is installed in the right hydraulic cavity. Such arrangement facilitates the assembly of the control valve structure.

[0048] like Figure 2 Figure 6 and Figure 8 As shown, in this embodiment, the gear reversing slide valve assembly 2 further includes a first left end cover 201 and a first right end cover 210; the left hydraulic part and the right hydraulic part are arranged at the left and right ends of the first valve body 108, and the left hydraulic part and the right hydraulic part are in an open shape. The first left end cover 201 is fixed to the left end of the first valve body 108 and blocks the left hydraulic part, and the first right end cover 210 is fixed to the right end of the first valve body 108 and blocks the right hydraulic part. Further, a first left sealing gasket 202 is arranged between the first left end cover 201 and the first valve body 108, and a first right sealing gasket 209 is arranged between the first right end cover 210 and the first valve body 108. Such an arrangement facilitates the assembly of the valve body.

[0049] In this embodiment, the gear reversing slide valve assembly 2 further includes a left positioning piston 203 and a right positioning piston 208; the left positioning piston 203 is slidably installed in the left hydraulic part, and the right positioning piston 208 is slidably installed in the right hydraulic part; the left positioning piston 203 divides the left hydraulic part into an H chamber 2031 and a G chamber 2032, and the G chamber 2032 is connected to the reversing part; the right positioning piston 208 divides the right hydraulic part into an E chamber 2081 and an F chamber 2082, and the F chamber 2082 is connected to the reversing part. With such a configuration, the piston and the reversing valve are controlled only by the pressure of the oil, thereby making the control of the gear reversing valve more precise.

[0050] like Figure 1 and Figure 6 As shown, in this embodiment, a pressure regulating valve assembly 1 is also installed on the first valve body 108, and the pressure regulating valve assembly 1 includes a second left end cover 101, a throttling screw 102, a second left sealing gasket 101, a small piston 204, a spring group 105, a pressure regulating spacer 106, a large piston 107, a second right sealing gasket 103, a second right cover plate 110, an upper cover plate sealing gasket 111 and an upper cover plate 112;

[0051] The second left end cover 101 and the second right cover plate 110 are respectively installed at the left and right ends of the first valve body 108, and the second left end cover 101 and the second right cover plate 110 block the two ends of the pressure regulating hole; a second left sealing gasket 101 is arranged between the second left end cover 101 and the first valve body 108, and a second right sealing gasket 103 is arranged between the second right cover plate 110 and the first valve body 108;

[0052] The first valve body 108 is provided with a pressure regulating hole, and the small piston 204 and the large piston 107 are both slidably installed in the pressure regulating hole, the small piston 204 is arranged on the left side of the pressure regulating hole, and the large piston 107 is arranged on the right side of the pressure regulating hole;

[0053] The spring group 105 is disposed between the small piston 204 and the large piston 107, and the two ends of the spring group 105 are respectively against the small piston 204 and the large piston 107;

[0054] A U cavity 1401 is arranged between the second left end cover 101 and the small piston 204, a V cavity 1402 and a C cavity 1403 are arranged between the small piston 204 and the inner wall of the pressure regulating hole, and the V cavity 1402 is located between the U cavity 1401 and the C cavity 1403; a throttling oil passage is opened on the large piston 107, the U cavity 1401 and the V cavity 1402 are connected through the throttling oil passage, and the throttling screw 102 is installed on the throttling oil passage.

[0055] Among them, moving the large piston 107 can make the V chamber 1402 and the C chamber 1403 communicate with each other; an oil outlet is provided at the C chamber 1403. A D chamber 1071 is provided between the second right cover plate 110 and the large piston 107. A second inner oil passage connecting the P chamber 2042 and the D chamber 1071 is provided on the first valve body 108, and the oil inlet of the first valve body 108 is communicated with the second inner oil passage.

[0056] This arrangement can control the oil pressure entering the gear shift regulating slide valve.

[0057] In this embodiment, a first inner oil passage connecting the K chamber 2043 and the D chamber 1071 is provided on the first valve body 108, and a throttle valve 4 and a one-way valve 5 are installed everywhere in the first inner oil passage, and the throttle valve 4 and the one-way valve 5 are arranged in parallel.

[0058] In this embodiment, the spring group 105 includes a large spring and a small spring, and the large spring is sleeved on the small spring; the right end of the large piston 107 is provided with a first receiving groove, and the left end of the small piston 204 is provided with a second receiving groove; both ends of the large spring and the two ends of the small spring are inserted into the first receiving groove and the second receiving groove respectively. Such a configuration can effectively control the movement of the spring group, thereby improving the control accuracy of the control valve.

[0059] Furthermore, a pressure regulating spacer 106 is fixed in the pressure regulating hole, and the pressure regulating spacer 106 is arranged between the second right cover plate 110 and the small piston 204 .

[0060] like Figure 2 and Figure 5 As shown, in this embodiment, an upper cover plate 112 is fixed on the top of the first valve body 108, and an upper sealing gasket 111 is arranged between the first valve body 108 and the upper cover plate 112. Such an arrangement facilitates the assembly of the control valve.

[0061] like Figure 1 , Figure 2 and Figure 8 As shown, in this embodiment, a solenoid reversing valve assembly is also included; the solenoid reversing valve assembly includes a second valve body 304 and a neutral solenoid valve 302, a reverse solenoid valve 301 and a forward solenoid valve 303 installed on the second valve body 304;

[0062] The second valve body 304 is fixed on the upper cover plate 112;

[0063] The second valve body 304 is provided with a P oil port 2041, an A1 oil passage 3042, an A2 oil passage 3043, an A3 oil passage 3044 and a T1 oil return port 3045. The P oil port 2041 includes a P1 portion, a P2 portion and a P3 portion which are connected to each other. The P1 portion is connected to the F chamber 2082 through the A1 oil passage 3042, the P2 portion is connected to the E chamber 2081 and the H chamber 2031 through the A2 oil passage 3043, and the P3 portion is connected to the G chamber 2032 through the A3 oil passage; the P1 portion, the P2 portion and the P3 portion are all connected to the T1 oil return port 3045;

[0064] The reverse solenoid valve 301, the neutral solenoid valve 302 and the forward solenoid valve 303 are all installed on the second valve body 304; the forward solenoid valve 303 can control the passage between the P1 part and the A1 oil passage 3042 and the T1 oil return port 3045, the neutral solenoid valve 302 can control the passage between the P2 part and the A2 oil passage 3043 and the T1 oil return port 3045, and the forward solenoid valve 303 can control the passage between the P3 part and the A3 oil passage 3044 and the T1 oil return port 3045. In this way, the control accuracy and reaction speed of the control valve are improved by electronic control.

[0065] In this embodiment, the oil inlet on the first valve body 108 is communicated with the P oil port 2041 .

[0066] In this embodiment, the electromagnetic reversing valve assembly is a two-position three-way electromagnetic valve with a mechanical emergency device.

[0067] like Figure 1 As shown, the control process of the above electro-hydraulic control valve is as follows:

[0068] To ensure that the reversing valve core 204 is in the neutral position when starting, the electromagnet YV2 of the neutral solenoid valve 302 is generally energized first, and the electromagnet YV3 of the forward solenoid valve 303 and the electromagnet YV1 of the reverse solenoid valve 301 are not energized. After the oil enters the V cavity 1402 of the first valve body, a part of it enters the U cavity 1401 through the inner oil hole, pushing the small piston 204 to move right, the compression spring group 105 is compressed, and the V cavity 1402 and the C cavity 1403 are connected, and then a part of the oil is discharged through the C cavity 1403, and the other part of the oil enters the P cavity 2042 of the gear reversing slide valve assembly 2 and the P oil port 2041 of the electromagnetic reversing valve assembly at the same time;

[0069] Since the forward solenoid valve 303 and the reverse solenoid valve 301 are not energized, the A1 oil channel and the A3 oil channel are in a cut-off state, the P2 part of the P oil port is connected to the A2 oil channel 3043, and the oil entering the P oil port 2041 enters the H chamber 2031 and the E chamber 2081 of the first valve body 108 through the A2 oil channel 3043, thereby pushing the left positioning piston 203 to the right and the right positioning piston 208 to the left, until the left positioning piston 203 and the right positioning piston 208 are respectively in contact with the end faces of the left hydraulic part and the right hydraulic part of the reversing hole; the reversing valve core 204 moves to the neutral position under the action of the left positioning piston 203 and the right positioning piston 208, thereby causing the positioning steel ball to enter the neutral ring groove of the inner hole of the positioning sleeve 205.

[0070] Among them, the reversing slide valve assembly P chamber 2042 is cut off, K chamber 2043, A chamber 2045, B chamber 2044 and D chamber 1071 are all connected to T2 oil return port 2046, I gear clutch and II gear clutch are not working, and the hydraulic system is in a low pressure state. At this time, if the electromagnet YV2 loses power, the A2 oil channel 3043 is cut off, P2, H chamber 2031 and E chamber 2081 are all connected to T1 oil return port 3045, and the hydraulic system is in a pressure relief state; however, the reversing valve core 204 is still kept in the neutral position due to the role of positioning the steel ball, thereby realizing the power-off protection function.

[0071] When the electromagnet YV1 of the reverse solenoid valve 301 is energized, the P1 part is connected with the F chamber 2082 through the A1 oil channel, and the reversing valve core 204 moves leftward under the action of the oil until the positioning steel ball moves into the reverse ring groove 2051 of the inner hole of the positioning sleeve 205. At this time, the P chamber 2042, the K chamber 2043, the B chamber 2044 and the II gear clutch are connected, and the oil entering the K chamber 2043 enters the D chamber 1071 of the pressure regulating valve assembly 1 through the throttle valve 4. The oil entering the D chamber 1071 pushes the large piston 107 to move leftward and compresses the spring group 105, so that the pressure of the V chamber 1402 and the P chamber 2042 gradually rises to the set working pressure value, and the II gear clutch is in a working state;

[0072] At this time, if the electromagnet YV1 loses power, the A1 oil channel is cut off by the reverse solenoid valve 301, and the F chamber 2082 of the gear reversing slide valve assembly 2 is connected to the T1 oil return port 3045. At this time, the hydraulic system is in a pressure relief state, and the reversing valve core 204 remains in the reverse gear position under the action of the positioning steel ball, realizing the power-off protection function.

[0073] When the electromagnet YV3 of the forward solenoid valve 303 is energized, the P3 part of the P oil port 2041 is connected to the G chamber 2032 of the gear reversing slide valve assembly 2 through the A3 oil channel, and the reversing valve core 204 moves right under the action of the oil until the positioning steel ball enters the forward ring groove 2053 of the positioning sleeve 205. At this time, the P chamber 2042, the K chamber 2043, the A chamber 2045 and the I gear clutch are connected, and the oil entering the K chamber 2043 enters the D chamber 1071 of the pressure regulating valve assembly 1 through the throttle valve 4, and then the oil entering the D chamber 1071 pushes the large piston 107 to move left and compresses the spring group 105, thereby causing the pressure of the V chamber 1402 and the P chamber 2042 to gradually rise to the set working pressure value, and the I gear clutch gradually enters the working state.

[0074] At this time, if the electromagnet YV3 loses power, the A3 oil channel is cut off by the forward solenoid valve 303, and the G chamber 2032 of the gear adjustment slide valve assembly is connected to the T1 oil return port 3045, and the hydraulic pressure enters the pressure relief state, but the reversing valve core 204 still remains in the forward position due to the positioning of the steel ball, thereby realizing the power-off protection function.

[0075] As can be seen from the above, when a certain gear is achieved by energizing the electromagnet of the electromagnetic reversing valve assembly, even if the electromagnet of the gear loses power, the gear will not change due to the mechanical positioning of the reversing valve core 204; only when another electromagnet is energized can the gear state be changed and switched to the corresponding gear. However, two or more electromagnets must not be energized at the same time to prevent the occurrence of random gears.

[0076] The above gears can be realized not only by energizing the solenoid valves of the corresponding gears, but also by the mechanical emergency mechanism of the solenoid valves of the corresponding gears, and the effects of the two are exactly the same.

[0077] When the electro-hydraulic directional control valve is in the neutral gear, the system is always in a low-pressure state. Only when the clutch of a certain gear is engaged, the system pressure is increased to the set value, thereby reducing the energy loss of the prime mover.

[0078] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0079] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are illustrative and cannot be understood as limitations on the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and purpose of the present invention.

Claims

1. An electro-hydraulic reversing valve, characterized in that: It comprises a first valve body (108) and a gear-position reversing slide valve assembly (1) mounted on the first valve body (108), wherein the gear-position reversing slide valve assembly (1) comprises a reversing valve core (204), a positioning sleeve (205) and a retractable positioning member; The first valve body (108) is provided with a reversing hole, the reversing hole comprising a left hydraulic part, a reversing part and a right hydraulic part, and the two hydraulic parts are connected through the reversing part; The inner wall of the positioning sleeve (205) is provided with a reverse gear ring groove (2051), a neutral gear ring groove (2052) and a forward gear ring groove (2053) arranged axially; The reversing valve core (204) is slidably mounted in the reversing portion, and the reversing valve core (204) can be driven to move left and right by controlling the pressure in the two hydraulic portions, so that the end of the reversing valve core (204) can enter and exit the hydraulic portion; The positioning sleeve (205) is sleeved on the reversing valve core (204), and the positioning sleeve (205) is fixed in the first valve body (108); the positioning member is installed on the reversing valve core (204), and the end of the positioning member can protrude from the reversing valve core (204) and abut against the inner wall of the positioning sleeve (205).

2. An electro-hydraulic reversing valve according to claim 1, characterized in that: The positioning member comprises a positioning spring (207) and a steel ball (206); a positioning hole (2041) is provided on the reversing valve core (204); the positioning spring (207) and the steel ball (206) are arranged in the positioning hole (2041); and the positioning spring (207) can push the steel ball (206) to protrude from the reversing valve core (204).

3. An electro-hydraulic reversing valve according to claim 2, characterized in that: Two steel balls (206) are arranged at both ends of the positioning spring (207); the positioning spring (207) can push the two steel balls (206) to protrude from the reversing valve core (204) and insert into the reverse gear ring groove (2051), the neutral gear ring groove (2052) or the forward gear ring groove (2053).

4. The electro-hydraulic reversing valve according to claim 1, characterized in that: The reverse gear ring groove (2051), the neutral gear ring groove (2052) and the forward gear ring groove (2053) are V-shaped ring grooves.

5. The electro-hydraulic reversing valve according to claim 1, characterized in that: The positioning sleeve (205) is fixed in the right hydraulic unit.

6. The electro-hydraulic reversing valve according to claim 1, characterized in that: The gear-changing slide valve assembly (1) further comprises a first left end cover (201) and a first right end cover (210); the left hydraulic part and the right hydraulic part are arranged at the left and right ends of the first valve body (108); the left hydraulic part and the right hydraulic part are in an open shape; the first left end cover (201) is fixed to the left end of the first valve body (108) and blocks the left hydraulic part; the first right end cover (210) is fixed to the right end of the first valve body (108) and blocks the right hydraulic part.

7. The electro-hydraulic reversing valve according to claim 6, characterized in that: A first left sealing gasket (202) is provided between the first left end cover (201) and the first valve body (108), and a first right sealing gasket (209) is provided between the first right end cover (210) and the first valve body (108).

8. The electro-hydraulic reversing valve according to claim 1, characterized in that: The gear-changing slide valve assembly (1) further comprises a left positioning piston (203) and a right positioning piston (208); the left positioning piston (203) is slidably mounted in the left hydraulic part, and the right positioning piston (208) is slidably mounted in the right hydraulic part.

9. The electro-hydraulic reversing valve according to claim 1, characterized in that: A P chamber (2042), a K chamber (2043), an A chamber (2045), a B chamber (2044) and a T2 oil return port (2046) are arranged between the inner wall of the reversing portion and the reversing valve core (204); two K chambers (2043) are arranged on the left and right sides of the P chamber (2042); two K chambers (2043) are arranged between the A chamber (2045) and the B chamber (2044); the A chamber (2045) and the B chamber (2044) are located between the two T2 oil return ports (2046); the A chamber (2045) is communicated with the I gear clutch; and the B chamber (2044) is communicated with the II gear clutch.

10. The electro-hydraulic reversing valve according to claim 1, characterized in that: The I-gear clutch is the forward clutch, and the II-gear clutch is the reverse clutch.

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