Automatic switching valve

Abstract

The utility model relates to the technical field of hydraulic valves, in particular to an automatic switching valve. The automatic switching valve comprises a valve body and a valve element assembly, a reversing piece is elastically installed in the valve body, and the reversing piece can act in the radial direction of the valve body so as to apply axial acting force to the valve element assembly. The valve element assembly is installed in the valve body and provided with a first reversing position and a second reversing position. The valve element assembly is provided with a reversing stop shoulder, and when the valve element assembly is located at the first reversing position, the reversing piece abuts against the first side face of the reversing stop shoulder. When the valve element assembly is located at the second reversing position, the reversing piece abuts against the second side face of the reversing stop shoulder, and the first side face and the second side face are arranged oppositely. The reversing piece is installed at the circumferential position in the valve body, the axial length of the valve body is reduced, and therefore the size and the installation space of the automatic switching valve are reduced, and miniaturization of the automatic switching valve is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic valves, in particular to an automatic switching valve. Background Art

[0002] Traditional hydraulic cylinders need to achieve reciprocating motion through an automatic switching valve (also called a reversing valve) with a spool structure. The internal part of the existing automatic switching valve is driven by hydraulic oil to change the position of the internal spool core, thereby controlling the reciprocating motion of the hydraulic cylinder. In the valve body of the automatic switching valve, a spring is usually installed at the end of the spool core to provide the reversing pressure for the spool core. Since the installation space for the spring needs to be reserved in the valve body of the automatic switching valve, the size of the valve body is increased, resulting in a relatively large volume of the automatic switching valve, which requires more installation space and is not convenient for the installation and use of the automatic switching valve. Summary of the Utility Model

[0003] The purpose of the utility model is to provide an automatic switching valve to reduce the volume and installation space of the automatic switching valve and achieve the miniaturized design of the automatic switching valve.

[0004] To achieve this purpose, the technical solution adopted by the utility model is as follows:

[0005] The automatic switching valve includes a valve body and a spool core assembly. A reversing part is elastically installed in the valve body, and the reversing part can act in the radial direction of the valve body to apply an axial force to the spool core assembly.

[0006] The spool core assembly is installed in the valve body, and the spool core assembly has a first reversing position and a second reversing position; the spool core assembly has a reversing shoulder. When the spool core assembly is in the first reversing position, the reversing part abuts against the first side of the reversing shoulder; when the spool core assembly is in the second reversing position, the reversing part abuts against the second side of the reversing shoulder, and the first side and the second side are arranged back to back.

[0007] As an optional scheme of the automatic switching valve, the reversing shoulder includes a connecting end and a free end. Along the radial direction of the spool core assembly, the free end protrudes away from the axis of the spool core assembly relative to the connecting end; along the axial direction of the spool core assembly, the first side and the second side are respectively located on both sides of the free end, and the reversing part can move from the connecting end to the free end along the first side, or the reversing part can move from the free end to the connecting end along the second side.

[0008] As an optional scheme of the automatic switching valve, the first side and the second side are connected at an angle; or, the first side and the second side are smoothly connected to form an arc surface.

[0009] A receiving groove is provided inside the valve body. When the reversing member abuts against the first side surface or the second side surface, at least a part of the reversing member is located in the receiving groove, and the reversing shoulder can push the reversing member to retract into the receiving groove.

[0010] As an alternative to the automatic switching valve, the reversing member includes a stop member and a clamping ring. The stop member is movably installed on the inner wall of the valve body, and the stop member can move radially along the valve body. The clamping ring is elastically sleeved on the valve body and clamps the stop member.

[0011] When the valve core assembly is in the first reversing position, the stop member presses against the first side surface; when the valve core assembly is in the second reversing position, the stop member presses against the second side surface.

[0012] As an alternative to the automatic switching valve, the stop member is a sphere.

[0013] As an alternative to the automatic switching valve, the valve body includes a valve seat and a valve sleeve. The valve sleeve is connected to the valve seat, and the valve core assembly is installed in the valve sleeve.

[0014] The valve sleeve is provided with a receiving groove penetrating along the radial direction. The stop member is movably installed in the receiving groove and can move radially along the valve sleeve, so that the stop member protrudes from the inner wall of the valve sleeve and presses against the first side surface or the second side surface of the reversing shoulder.

[0015] As an alternative to the automatic switching valve, the receiving groove includes a connected installation groove and a through hole. The installation groove is circumferentially provided on the outer peripheral surface of the valve sleeve. The bottom wall of the installation groove is provided with the through hole along the radial direction. The clamping ring is elastically sleeved in the installation groove, and the stop member is movably installed in the through hole. When the valve core assembly is in the first reversing position or the second reversing position, one side of the stop member abuts against the first side surface or the second side surface, the other side of the stop member abuts against the clamping ring, and the clamping ring abuts against the bottom of the installation groove or has a gap.

[0016] As an alternative to the automatic switching valve, the valve body is provided with an oil return port T, an oil inlet port P, an oil port A and an oil port B spaced along the axial direction. The oil port A can be connected to the rodless cavity of the actuator, and the oil port B can be connected to the rod cavity of the actuator. The valve core assembly and the valve body enclose a first pilot cavity, a first annular cavity, a second annular cavity and a second pilot cavity arranged at intervals along the axial direction. The first pilot cavity is connected to the second annular cavity, and the second pilot cavity is connected to the first annular cavity. The reversing shoulder is located in the first pilot cavity.

[0017] When the spool assembly is in the first commutation position, the oil inlet P is communicated with the oil port A, and the oil port B is communicated with the oil return port T; when the spool assembly is in the second commutation position, the oil inlet P is communicated with the oil port B, and the oil port A is communicated with the oil return port T.

[0018] As an alternative to the automatic switching valve, the oil inlet P includes a first oil inlet and a second oil inlet arranged at intervals. The first oil inlet is arranged adjacent to the oil port B, and the second oil inlet is arranged adjacent to the oil port A.

[0019] The spool assembly includes a main spool and a slip ring. The slip ring is sleeved on the main spool and can move axially along the main spool. When the spool assembly is in the first commutation position, the slip ring blocks the first oil inlet, and the second oil inlet is communicated with the oil port A. When the spool assembly is in the second commutation position, the slip ring blocks the second oil inlet, and the first oil inlet is communicated with the oil port B.

[0020] As an alternative to the automatic switching valve, a limiting groove is circumferentially formed on the outer peripheral surface of the main spool, and the slip ring is sleeved in the limiting groove. When the spool assembly is in the first commutation position, the slip ring abuts against the first side wall of the limiting groove. When the spool assembly is in the second commutation position, the slip ring abuts against the second side wall of the limiting groove.

[0021] The beneficial effects of the present utility model are as follows:

[0022] For the automatic switching valve proposed by the present utility model, the commutation member acts radially along the valve body to apply an axial force to the spool assembly, thereby controlling the commutation of the automatic switching valve. Since the commutation member acts radially along the valve body, it does not need to occupy the axial space of the valve body, reducing the axial length of the valve body, thereby reducing the volume of the automatic switching valve and the installation space required, achieving miniaturization of the automatic switching valve. Description of the Drawings

[0023] Figure 1 is a cross-sectional view of the automatic switching valve in the first commutation position provided by an embodiment of the present utility model;

[0024] Figure 2 is a cross-sectional view of the automatic switching valve in the second commutation position provided by an embodiment of the present utility model;

[0025] Figure 3 is an exploded cross-sectional view of the structure of the valve body provided by an embodiment of the present utility model;

[0026] Figure 4 is an exploded cross-sectional view of the structure of the main spool provided by an embodiment of the present utility model.

[0027] The names and reference numerals of the components in the figure are as follows:

[0028] 1. Valve body; 11. Valve seat; 12. Valve sleeve; 120. Through hole; 121. Installation groove; 122. First oil inlet; 123. Second oil inlet; 124. First oil return port; 125. Second oil return port; 126. Oil port A; 127. Oil port B; 13. First pilot chamber; 14. First annular chamber; 15. Second annular chamber; 16. Second pilot chamber;

[0029] 2. Spool assembly; 21. Main spool; 210. Limit groove; 211. Valve cover; 2111. First channel; 212. First sliding spool; 2121. Second channel; 2122. Third channel; 2123. Commutation shoulder; 21231. Second side; 21232. First side; 21233. Connection end; 21234. Free end; 2124. Left shoulder; 213. Second sliding spool; 2131. Fourth channel; 2132. Fifth channel; 2133. Right shoulder; 22. Slip ring;

[0030] 3. Stop piece; 4. Holding ring. Detailed implementation manners

[0031] To make the technical problems solved by the present utility model, the technical solutions adopted and the achieved technical effects clearer, the technical solutions of the present utility model will be further described below with reference to the accompanying drawings and through specific implementation manners. It can be understood that the specific embodiments described herein are only used to explain the present utility model, rather than limiting the present utility model. In addition, it should be noted that for the sake of description, only the parts related to the present utility model are shown in the accompanying drawings rather than all of them.

[0032] In the description of the present utility model, unless otherwise clearly defined and limited, the terms "connected", "connected", "fixed" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0033] In the present utility model, unless otherwise clearly specified and defined, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may also include the situation where the first and second features are not in direct contact but are in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0034] In the description of this embodiment, the orientation or positional relationships such as "above", "below", "right", "left", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0035] The technical solution of the present utility model will be further described below in conjunction with the drawings and through specific embodiments.

[0036] This embodiment provides a dynamic switching valve, which is mainly used to control the commutation operation of a hydraulic cylinder. Specifically, a rodless cavity and a rod cavity are provided in the cylinder body of the hydraulic cylinder, and the automatic switching valve is installed on the cylinder body to adjust the amount of oil (i.e., hydraulic oil) in the rodless cavity and the rod cavity through the automatic switching valve, so as to control the piston rod of the hydraulic cylinder to extend or retract into the cylinder body to complete the reciprocating motion of the hydraulic cylinder.

[0037] In the existing automatic switching valve, the internal position transformation is realized by driving the internal spool valve core through hydraulic oil to control the reciprocating motion of the hydraulic cylinder. In the valve body of the automatic switching valve, springs are installed at one end or both ends of the spool valve core axially to control the commutation pressure of the spool valve core through the springs. Since the installation space for the springs needs to be reserved in the valve body of the automatic switching valve, the axial length of the valve body is increased, resulting in a relatively large volume of the automatic switching valve, which requires more installation space and is not convenient for the installation and use of the automatic switching valve.

[0038] To solve the above problems, as Figures 1 to 4As shown in the figure, the automatic switching valve of this embodiment includes a valve body 1 and a valve core assembly 2. A reversing member is elastically installed in the valve body 1. The reversing member can move radially along the valve body 1 to apply an axial force to the valve core assembly 2. The valve core assembly 2 is installed in the valve body 1. The valve core assembly 2 has a first reversing position and a second reversing position. The valve core assembly 2 has a reversing shoulder 2123. When the valve core assembly 2 is in the first reversing position, the reversing member abuts against the first side 21232 of the reversing shoulder 2123. When the valve core assembly 2 is in the second reversing position, the reversing member abuts against the second side 21231 of the reversing shoulder 2123. The first side 21232 and the second side 21231 are arranged back to back. By the radial movement of the reversing member along the valve body 1, an axial force is applied to the valve core assembly 2, thereby controlling the reversing of the automatic switching valve. Since the reversing member moves radially along the valve body 1, it does not need to occupy the axial (left and right direction in the figure) space of the valve body 1, reducing the axial length of the valve body 1, thereby reducing the volume of the automatic switching valve and the required installation space, facilitating installation and use, and realizing the miniaturization of the automatic switching valve.

[0039] Specifically, the reversing member includes a stop member 3 and a retaining ring 4. The stop member 3 is movably installed on the inner wall of the valve body 1, and the stop member 3 can move radially along the valve body 1. The retaining ring 4 is elastically sleeved on the valve body 1 and holds the stop member 3 tightly. In the valve body 1 of this embodiment, a plurality of stop members 3 are arranged at intervals along the circumferential direction of the inner wall, and the stop members 3 can move radially along the valve body 1. The retaining ring 4 is elastically sleeved in the valve body 1 and holds the plurality of stop members 3 tightly. The valve core assembly 2 is installed in the valve body 1 and has a first reversing position where it moves to the left end of the valve body 1 and a second reversing position where it moves to the right end of the valve body 1. The valve body 1 has a receiving groove. When the valve core assembly 2 moves between the first reversing position and the second reversing position, the reversing shoulder 2123 pushes the stop member 3 to retract into the receiving groove of the valve body 1. When the valve core assembly 2 is in the first reversing position, the stop member 3 abuts against the first side 21232 of the reversing shoulder 2123. When the valve core assembly 2 is in the second reversing position, the stop member 3 abuts against the second side 21231 of the reversing shoulder 2123 to limit the reversing of the automatic switching valve.

[0040] In this embodiment, the stop member 3 is a sphere, so that the stop member 3 and the reversing shoulder 2123 are in point contact, reducing the contact area between the stop member 3 and the reversing shoulder 2123, thereby reducing the wear amount of the reversing shoulder 2123 and improving the protection of the valve core assembly 2. The stop member 3 is a steel ball, and the steel ball has high structural strength and wear resistance to improve the service life of the stop member 3. The retaining ring 4 is a wire retaining ring. The wire retaining ring has high structural strength. At the same time, the wire retaining ring can hold the plurality of steel balls tightly to press against the second side 21231 or the first side 21232 of the reversing shoulder 2123 through the steel balls, thereby controlling the reversing pressure of the automatic switching valve. Of course, according to different reversing pressures, parameters such as the material and diameter of the retaining ring 4 can be adjusted.

[0041] As Figure 3 shown, the valve body 1 is axially provided with an oil return port T, an oil inlet port P, an oil port A126 and an oil port B127 at intervals. The oil port A126 can communicate with the rodless cavity of the actuator, and the oil port B127 can communicate with the rod cavity of the actuator. The spool assembly 2 and the valve body 1 enclose a first pilot cavity 13, a first annular cavity 14, a second annular cavity 15 and a second pilot cavity 16 which are arranged at intervals along the axis in sequence. The first pilot cavity 13 communicates with the second annular cavity 15, and the second pilot cavity 16 communicates with the first annular cavity 14. The commutation shoulder 2123 is located in the first pilot cavity 13. As Figure 1 shown, when the spool assembly 2 is in the first commutation position, the oil inlet port P communicates with the oil port A126, and the oil port B127 communicates with the oil return port T. As Figure 2 shown, when the spool assembly 2 is in the second commutation position, the oil inlet port P communicates with the oil port B127, and the oil port A126 communicates with the oil return port T. The actuator in this embodiment is a hydraulic cylinder.

[0042] It should be noted that the oil inlet port P communicates with an external oil supply pipe to input high-pressure hydraulic oil into the oil inlet port P through mechanisms such as an oil pump. The oil return port T communicates with an external oil tank to enable the hydraulic oil to flow back into the oil tank, and the oil pressure at the time of oil inlet at the oil inlet port P is much greater than the oil pressure at the oil return port T.

[0043] Along Figure 1 the trajectory indicated by the arrow, when the spool assembly 2 is in the first commutation position, a part of the external high-pressure hydraulic oil flows into the rodless cavity through the oil inlet port P and the oil port A126, and another part of the hydraulic oil flows into the left first pilot cavity 13. The hydraulic oil in the rod cavity flows back to the oil tank through the oil port B127 and the oil return port T, so that the piston rod in the cylinder moves from left to right. After the piston rod moves to the extreme position to the right, the oil pressure in the first pilot cavity 13 continues to increase until the stopper 3 can be pushed into the inner wall of the valve body 1, the holding ring 4 expands, and the commutation shoulder 2123 moves from the left side of the stopper 3 to the right side. At this time, the stopper 3 is pressed against the second side surface 21231 of the commutation shoulder 2123 under the action of the elastic restoring force of the holding ring 4. Along Figure 2The trajectory indicated by the arrow. When the spool assembly 2 is in the second commutation position, a part of the external high-pressure hydraulic oil flows into the rod chamber through the oil inlet P and the oil port B127, and another part of the hydraulic oil flows into the second pilot chamber 16 on the right side. The hydraulic oil in the rodless chamber flows back to the oil tank through the oil port A126 and the oil return port T, so that the piston rod in the cylinder moves from right to left. After the piston rod moves to the extreme position to the left, the oil pressure in the second pilot chamber 16 continues to increase until the stopper 3 can be pushed into the inner wall of the valve body 1, the holding ring 4 expands again, and the commutation shoulder 2123 moves from the right side of the stopper 3 to the left side. At this time, the stopper 3 presses against the first side 21232 of the commutation shoulder 2123 under the action of the elastic restoring force of the holding ring 4, and cycles in turn, so as to control the reciprocating motion of the hydraulic cylinder through the automatic switching valve.

[0044] Specifically, as Figure 3 shown, the oil inlet P includes a first oil inlet 122 and a second oil inlet 123 arranged at intervals. The first oil inlet 122 is adjacent to the oil port B127, and the second oil inlet 123 is adjacent to the oil port A126. The spool assembly 2 includes a main spool 21 and a slip ring 22. The slip ring 22 is sleeved on the main spool 21 and can move axially along the main spool 21. When the spool assembly 2 is in the first commutation position, the slip ring 22 moves to the left side of the main spool 21 axially and blocks the first oil inlet ......

[0045] It should be noted that the content in the middle of the translation of item is incomplete in the original text you provided. I have translated it as much as possible according to the existing content. You can check and supplement the complete content for a more accurate translation.It should be noted that when the spool assembly 2 is in the first commutation position, the second oil inlet 123 is communicated with the oil port A 126, so that the high-pressure hydraulic oil entering the second oil inlet 123 can push the sliding ring 22 to move from right to left to the first oil inlet 122 and block the first oil inlet 122. When the spool assembly 2 is in the second commutation position, the first oil inlet 122 is communicated with the oil port B 127, so that the high-pressure hydraulic oil entering the first oil inlet 122 can push the sliding ring 22 to move from left to right to the second oil inlet 123 and block the second oil inlet 123. Compared with the design scheme in which the sliding ring 22 and the main spool 21 are of an integral structure, the sliding ring 22 and the main spool 21 in this embodiment are of a split structure, so that the main spool 21 and the sliding ring 22 can move independently along the axial direction, and the moving length of the main spool 21 between the first commutation position and the second commutation position is not limited by the axial distance between the first oil inlet 122 and the second oil inlet 123 along the valve body 1. Therefore, when the distance between the first oil inlet 122 and the second oil inlet 123 is relatively large, the spool assembly 2 does not need to move a large displacement during commutation, which is beneficial to further reducing the axial space of the valve body 1, and thus further reducing the volume of the automatic switching valve and the installation space required.

[0046] Further, as Figure 1 and Figure 2 , a limiting groove 210 is circumferentially formed on the outer peripheral surface of the main spool 21, and the sliding ring 22 is sleeved in the limiting groove 210. When the spool assembly 2 is in the first commutation position, the sliding ring 22 abuts against the first side wall of the limiting groove 210. When the spool assembly 2 is in the second commutation position, the sliding ring 22 abuts against the second side wall of the limiting groove 210. By providing the limiting groove 210, the sliding of the sliding ring 22 in the left-right direction can be limited, so that the sliding ring 22 stays on the first side wall or the second side wall of the limiting groove 210, so that the sliding ring 22 can reliably block the first oil inlet 122 or the second oil inlet 123.

[0047] As Figures 1 to 3As shown, the oil return port T includes a first oil return port 124 and a second oil return port 125 which are arranged at intervals. The first oil return port 124 is adjacent to the oil port B127, and the second oil return port 125 is adjacent to the oil port A126. When the spool assembly 2 is in the first commutation position, the first oil return port 124 is communicated with the oil port B127, and the spool assembly 2 blocks the second oil return port 125; when the spool assembly 2 is in the second commutation position, the second oil return port 125 is communicated with the oil port A126, and the spool assembly 2 blocks the first oil return port 124. By providing two oil return ports, the oil port A126 and the oil port B127 can be selectively communicated with their respective adjacent oil return ports, optimizing the oil port distribution in the automatic switching valve. At the same time, left shoulders 2124 and right shoulders 2133 are provided at the left and right ends of the main spool 21. The first oil return port 124 is blocked by the left shoulder 2124 of the main spool 21, and the second oil return port 125 is blocked by the right shoulder 2133 of the main spool 21 to ensure the reliable opening and closing of the two oil return ports.

[0048] As Figure 1 and Figure 2 shown, a first flow channel and a second flow channel are opened in the main spool 21. The first pilot chamber 13, the first flow channel and the second annular chamber 15 are communicated in sequence, and the second pilot chamber 16, the second flow channel and the first annular chamber 14 are communicated in sequence. By opening two flow channels in the main spool 21, part of the high-pressure hydraulic oil can flow to the first pilot chamber 13 through the first flow channel or to the second pilot chamber 16 through the second flow channel, optimizing the hydraulic flow channel layout and simplifying the structure of the automatic switching valve.

[0049] Specifically, as Figure 1 , Figure 2 and Figure 4 shown, the main spool 21 includes a valve cover 211, a first spool 212 and a second spool 213 which are connected in sequence. A commutation shoulder 2123 is provided on the outer periphery of the first spool 212. The valve cover 211 is provided with a first channel 2111, the first spool 212 is provided with a second channel 2121 and a third channel 2122, the second spool 213 is provided with a fourth channel 2131 and a fifth channel 2132. One end of the first channel 2111 is communicated with the first pilot chamber 13, and one end of the fourth channel 2131 is communicated with the second annular chamber 15. The other end of the first channel 2111, the second channel 2121 and the other end of the fourth channel 2131 are communicated in sequence to form a first flow channel. One end of the third channel 2122 is communicated with the first annular chamber 14, one end of the fifth channel 2132 is communicated with the second pilot chamber 16, and the other end of the third channel 2122 is communicated with the other end of the fifth channel 2132 to form a second flow channel. By setting the main spool 21 into a split structure of a valve cover 211, a first spool 212 and a second spool 213, it is convenient to disassemble and assemble the main spool 21. At the same time, the processing difficulty of the first flow channel and the second flow channel is reduced, saving costs.

[0050] Specifically, the valve cover 211 has a T-shaped structure. The valve cover 211 is screwed and installed at the left end of the first spool 212 through a threaded connection. The right end of the first spool 212 and the second spool 213 can be connected as a whole by means of crimping, threaded connection or interference fit. The above assembly method not only improves the assembly efficiency of the main spool 21, but also improves the structural strength of the main spool 21. It should be noted that the right end of the first spool 212 can be coaxially provided with an annular groove with internal threads, and the left end of the second spool 213 is threadedly connected into the annular groove. By coaxially and threadedly connecting the first spool 212 and the second spool 213, it is ensured that the first channel 2111, the second channel 2121 and the fourth channel 2131 are sequentially connected to form a first flow path, and at the same time, the third channel 2122 and the fifth channel 2132 are connected to form a second flow path.

[0051] In this embodiment, a commutation shoulder 2123 and a left shoulder 2124 are axially spaced along the outer periphery of the first spool 212. A right shoulder 2133 is provided at one end (i.e., the right end) of the second spool 213 away from the first spool 212. The left end of the second spool 213 has a stepped shaft structure. The right end of the first spool 212 and the left end of the second spool 213 are assembled together to form a limiting groove 210. The sliding ring 22 is sleeved on the second spool 213 and can move left and right in the limiting groove 210. When the spool assembly 2 is installed in the valve body 1, the cavity on the left side of the left shoulder 2124 is the first pilot cavity 13, the cavity between the left shoulder 2124 and the sliding ring 22 is the first annular cavity 14, the cavity between the sliding ring 22 and the right shoulder 2133 is the second annular cavity 15, and the cavity formed by the right end of the second spool 213 and the valve sleeve 12 is the second pilot cavity 16.

[0052] It should be noted that the commutation shoulder 2123 is located in the first pilot cavity 13, and the commutation shoulder 2123 divides the first pilot cavity 13 into two interconnected left and right parts. One end of the second channel 2121 in the first spool 212 is connected to the fourth channel 2131, and the other end of the second channel 2121 has two branch channels. One branch channel is connected to the first channel 2111 to deliver part of the hydraulic oil to the left space of the first pilot cavity 13 through the first channel 2111, and the other branch channel is connected to the right space of the first pilot cavity 13 to ensure that the hydraulic oil is evenly injected into the first pilot cavity 13.

[0053] As Figures 1 to 3As shown in the figure, the valve body 1 includes a valve seat 11 and a valve sleeve 12, and the valve sleeve 12 is connected to the valve seat 11. The valve core assembly 2 is installed inside the valve sleeve 12. The valve sleeve 12 is provided with a receiving groove penetrating in the radial direction. The stopper 3 is movably installed in the receiving groove and can move along the radial direction of the valve sleeve 12, so that the stopper 3 protrudes from the inner wall of the valve sleeve 12 and presses against the first side surface 21232 or the second side surface 21231 of the commutation shoulder 2123. By setting the valve body 1 as a split structure of the valve seat 11 and the valve sleeve 12, it is convenient for the processing and manufacturing of the valve body 1 and reduces the processing difficulty of the valve body 1.

[0054] Specifically, the receiving groove includes a connected installation groove 121 and a through hole 120. The outer peripheral surface of the valve sleeve 12 is circumferentially provided with an installation groove 121, and the bottom wall of the installation groove 121 is provided with a through hole 120 in the radial direction. The clamping ring 4 is elastically sleeved in the installation groove 121, and the stopper 3 is movably installed in the through hole 120. When the valve core assembly 2 is in the first commutation position or the second commutation position, one side of the stopper 3 abuts against the first side surface 21232 or the second side surface 21231, and the other side of the stopper 3 abuts against the clamping ring 4. The clamping ring 4 abuts against the bottom of the installation groove 121 or has a gap. Specifically, the valve sleeve 12 is provided with a plurality of through holes 120 at intervals in the circumferential direction. The through holes 120 are communicated with the inside of the valve sleeve 12. The plurality of stoppers 3 are respectively movably installed in the corresponding through holes 120 and can telescopically move along the radial direction of the valve sleeve 12, so that the stoppers 3 protrude from the inner wall of the valve sleeve 12 and press against the commutation shoulder 2123 or retract into the corresponding through holes 120. The axial direction of the through hole 120 in this embodiment is parallel to the radial direction of the valve sleeve 12, so that the stopper 3 can extend or retract along the through hole 120, providing a guiding and limiting effect for the telescopic movement of the stopper 3 along the radial direction of the valve sleeve 12.

[0055] When the spool assembly 2 is in the first commutation position, the stopper 3 presses against the first side surface 21232 of the commutation shoulder 2123, and the holding ring 4 applies an elastic holding force to the stopper 3, causing the stopper 3 to tightly press against the first side surface 21232 of the commutation shoulder 2123. When the oil pressure in the first pilot chamber 13 increases to the set value, the spool assembly 2 moves from left to right under the push of the oil pressure. At this time, the commutation shoulder 2123 pushes the stopper 3 into the through hole 120. When the stopper 3 slides to the left side of the commutation shoulder 2123, the oil pressure in the first pilot chamber 13 drops, and the stopper 3 protrudes from the inner wall of the valve sleeve 12 again under the action of the elastic holding force of the holding ring 4 and presses against the second side surface 21231 of the commutation shoulder 2123. At this time, the oil pressure in the second pilot chamber 16 will gradually increase to the set value, and the spool assembly 2 moves from right to left under the push of the oil pressure. At this time, the commutation shoulder 2123 pushes the stopper 3 into the through hole 120 again. When the stopper 3 slides to the right side of the commutation shoulder 2123, the oil pressure in the second pilot chamber 16 drops, and the stopper 3 protrudes from the inner wall of the valve sleeve 12 again under the action of the elastic holding force of the holding ring 4 and presses against the first side surface 21232 of the commutation shoulder 2123. By repeating this cycle, the automatic commutation operation of the automatic switching valve is achieved.

[0056] As Figure 1 , Figure 2 and Figure 4 shown, the commutation shoulder 2123 includes a connecting end 21233 and a free end 21234. Along the radial direction of the spool assembly 2, the free end 21234 protrudes away from the axis of the spool assembly 2 relative to the connecting end 21233. Along the axial direction of the spool assembly 2, the first side surface 21232 and the second side surface 21231 are respectively located on both sides of the free end 21234. The commutation member can move from the connecting end 21233 to the free end 21234 along the first side surface 21232, or the commutation member can move from the free end 21234 to the connecting end 21233 along the second side surface 21231.

[0057] The second side surface 21231 of this embodiment is connected to the first side surface 21232 at an angle, so that the commutation shoulder 2123 is a V-shaped shoulder. A receiving groove is provided in the valve body 1. When the commutation member abuts against the first side surface 21232 or the second side surface 21231, at least part of the commutation member is located in the receiving groove, and the commutation shoulder 2123 can push the commutation member to retract into the receiving groove. Since the second side surface 21231 and the first side surface 21232 of the commutation shoulder 2123 are inclined, the stop member 3 can reciprocate between the second side surface 21231 and the first side surface 21232, which plays a good guiding role for the stop member 3 and avoids situations such as jamming of the stop member 3 with the commutation shoulder 2123, thereby realizing the automatic commutation operation of the automatic switching valve. In other embodiments, the first side surface 21232 and the second side surface 21231 are smoothly connected to form an arc surface, that is, the radial cross-section of the commutation shoulder 2123 is arc-shaped.

[0058] As Figure 4 shown, the included angle α between the second side surface 21231 and the first side surface 21232 is 90° to 150°. For example, the included angle α can be 90°, 100°, 110°, 120°, 130°, 140° or 150°, etc., to ensure that the stop member 3 reciprocates between the second side surface 21231 and the first side surface 21232 of the commutation shoulder 2123 to change positions. When the included angle α is too small (less than 90°), the slopes of the inclined second side surface 21231 and the first side surface 21232 are large. During the commutation process of the automatic switching valve, the commutation shoulder 2123 is likely to jam with the stop member 3, resulting in the locking of the valve core assembly 2 in the first commutation position or the second commutation position, causing the automatic switching valve to fail or be damaged; when the included angle α is too large (greater than 150°), the slopes of the inclined second side surface 21231 and the first side surface 21232 are small, reducing the limiting effect of the stop member 3 on the commutation shoulder 2123, thereby reducing the commutation pressure.

[0059] The above embodiments only illustrate the basic principles and characteristics of the present invention. The present invention is not limited by the above embodiments. Without departing from the spirit and scope of the present invention, there are various changes and modifications to the present invention, and these changes and modifications all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. Automatic switching valve, characterized in that, It comprises a valve body (1) and a valve core assembly (2), wherein a reversing member is elastically installed in the valve body (1), and the reversing member can move along the radial direction of the valve body (1) to apply an axial force to the valve core assembly (2); The valve core assembly (2) is installed in the valve body (1), and the valve core assembly (2) has a first reversing position and a second reversing position; the valve core assembly (2) has a reversing shoulder (2123), and when the valve core assembly (2) is located at the first reversing position, the reversing member presses against the first side surface (21232) of the reversing shoulder (2123); when the valve core assembly (2) is located at the second reversing position, the reversing member presses against the second side surface (21231) of the reversing shoulder (2123), and the first side surface (21232) and the second side surface (21231) are arranged opposite to each other.

2. The automatic switching valve according to claim 1, characterized in that: The reversing shoulder (2123) includes a connecting end (21233) and a free end (21234). Along the radial direction of the valve core assembly (2), the free end (21234) protrudes relative to the connecting end (21233) toward a side away from the axis of the valve core assembly (2); along the axial direction of the valve core assembly (2), the first side surface (21232) and the second side surface (21231) are respectively located on both sides of the free end (21234). The reversing member can move from the connecting end (21233) to the free end (21234) along the first side surface (21232), or the reversing member can move from the free end (21234) to the connecting end (21233) along the second side surface (21231).

3. The automatic switching valve according to claim 2, characterized in that: The first side surface (21232) and the second side surface (21231) are connected at an angle; or, the first side surface (21232) and the second side surface (21231) are smoothly connected to form an arc surface; A receiving groove is provided in the valve body (1); when the reversing member abuts against the first side surface (21232) or the second side surface (21231), at least a portion of the reversing member is located in the receiving groove, and the reversing shoulder (2123) can push the reversing member to retract into the receiving groove.

4. The automatic switching valve according to claim 1, characterized in that: The reversing member comprises a stopper (3) and an embracing ring (4); the stopper (3) is movably mounted on the inner wall of the valve body (1), and the stopper (3) is capable of moving in the radial direction of the valve body (1); the embracing ring (4) is elastically sleeved on the valve body (1) and embracing the stopper (3); When the valve core assembly (2) is located at the first reversing position, the stopper (3) presses against the first side surface (21232); when the valve core assembly (2) is located at the second reversing position, the stopper (3) presses against the second side surface (21231).

5. The automatic switching valve according to claim 4, characterized in that: The stopper (3) is a sphere.

6. The automatic switching valve according to claim 4, characterized in that: The valve body (1) comprises a valve seat (11) and a valve sleeve (12), the valve sleeve (12) is connected to the valve seat (11), and the valve core assembly (2) is installed in the valve sleeve (12); The valve sleeve (12) is provided with a receiving groove extending radially therethrough, and the stopper (3) is movably mounted in the receiving groove and is capable of moving radially along the valve sleeve (12), so that the stopper (3) protrudes from the inner wall of the valve sleeve (12) and presses against the first side surface (21232) or the second side surface (21231) of the reversing shoulder (2123).

7. The automatic switching valve according to claim 6, characterized in that: The accommodating groove comprises a connecting mounting groove (121) and a through hole (120); the outer peripheral surface of the valve sleeve (12) is circumferentially provided with the mounting groove (121); the bottom wall of the mounting groove (121) is radially provided with the through hole (120); the holding ring (4) is elastically sleeved in the mounting groove (121); and the stopper (3) is movably installed in the through hole (120); when the valve core assembly (2) is located at the first reversing position or the second reversing position, one side of the stopper (3) abuts against the first side surface (21232) or the second side surface (21231), and the other side of the stopper (3) abuts against the holding ring (4); the holding ring (4) abuts against the bottom of the mounting groove (121) or has a gap therebetween.

8. The automatic switching valve according to any one of claims 1 to 7, characterized in that: The valve body (1) is provided with an oil return port T, an oil inlet port P, an oil port A (126) and an oil port B (127) spaced apart in the axial direction, the oil port A (126) can be communicated with the rodless cavity of the actuator, and the oil port B (127) can be communicated with the rod cavity of the actuator; the valve core assembly (2) and the valve body (1) enclose a first pilot cavity (13), a first annular cavity (14), a second annular cavity (15) and a second pilot cavity (16) which are arranged in sequence in the axial direction; the first pilot cavity (13) is communicated with the second annular cavity (15), and the second pilot cavity (16) is communicated with the first annular cavity (14); the reversing shoulder (2123) is located in the first pilot cavity (13); When the valve core assembly (2) is located at the first reversing position, the oil inlet P is communicated with the oil port A (126), and the oil port B (127) is communicated with the oil return port T; when the valve core assembly (2) is located at the second reversing position, the oil inlet P is communicated with the oil port B (127), and the oil port A (126) is communicated with the oil return port T.

9. The automatic switching valve according to claim 8, characterized in that: The oil inlet P comprises a first oil inlet (122) and a second oil inlet (123) arranged at intervals, the first oil inlet (122) being adjacent to the oil port B (127), and the second oil inlet (123) being adjacent to the oil port A (126); The valve core assembly (2) comprises a main valve core (21) and a slip ring (22), wherein the slip ring (22) is sleeved on the main valve core (21) and can move along the axial direction of the main valve core (21); when the valve core assembly (2) is located at the first reversing position, the slip ring (22) blocks the first oil inlet (122), and the second oil inlet (123) is connected to the oil port A (126); when the valve core assembly (2) is located at the second reversing position, the slip ring (22) blocks the second oil inlet (123), and the first oil inlet (122) is connected to the oil port B (127).

10. The automatic switching valve according to claim 9, characterized in that: The outer peripheral surface of the main valve core (21) is provided with a limiting groove (210) along the circumferential direction, and the slip ring (22) is sleeved in the limiting groove (210); when the valve core assembly (2) is located at the first reversing position, the slip ring (22) abuts against the first side wall of the limiting groove (210); when the valve core assembly (2) is located at the second reversing position, the slip ring (22) abuts against the second side wall of the limiting groove (210).

Images