Overflow valve
By forming the piston sleeve and the plug in one piece and combining the pressure relief channel design, the problem of many parts of the relief valve is solved, cost saving and stability improvement are achieved, and the oil pressure is appropriate.
Patent Information
- Application Number
- CN202422553065.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-22
- Publication Date
- 2025-07-22
- Estimated Expiration
- 2034-10-22
AI Technical Summary
The existing relief valve has a large number of parts, resulting in high costs and insufficient operating stability and reliability of the slide valve core.
The piston sleeve and the plug are arranged in an integrated molding structure, and the slide valve core and the plug are directly slidably cooperated, and a pressure relief channel is formed between the slide valve core and the plug, connecting the first chamber and the liquid outlet.
Reduces the number of parts, saves costs, and improves the operation stability and reliability of the slide valve core, ensuring the appropriate oil pressure and avoiding the phenomenon of holding the pressure.
Smart Images
Figure CN223137064U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of overflow valves, and particularly relates to an overflow valve. Background Art
[0002] Currently, in an overflow valve, a piston sleeve is usually arranged in a valve seat, a plug is arranged at one end of the piston sleeve, and a spool is slidably fitted in the valve seat and the piston sleeve respectively, so as to provide a guiding and limiting function for the sliding of the spool; however, the above structure results in a large number of components of the overflow valve, making the cost of the whole overflow valve relatively high.
[0003] Aiming at the above problems, an overflow valve is urgently needed to solve the above problems. Summary of the Utility Model
[0004] The purpose of the utility model is to provide an overflow valve, which can integrally form a structure with a piston sleeve and a plug, can reduce the number of components, save costs, and can improve the action stability and reliability of the spool, and ensure that the oil pressure in the overflow valve is relatively appropriate.
[0005] To achieve the above object, the utility model adopts the following technical solutions:
[0006] An overflow valve, comprising:
[0007] A first valve seat, on which a liquid outlet is provided;
[0008] A second valve seat and a spool, at least part of the second valve seat is located in the first valve seat, and part of the spool is slidably fitted in the second valve seat;
[0009] A plug, at least part of the plug is arranged at one end of the second valve seat away from the liquid outlet, part of the spool is slidably fitted in the plug, and a first chamber is formed between the spool and the plug;
[0010] A pressure relief channel, at least part of the pressure relief channel is arranged in the plug and / or the second valve seat and / or the first valve seat, and the pressure relief channel communicates the first chamber with the liquid outlet.
[0011] As an optional solution, the overflow valve has a pressure building chamber for establishing pressure on both sides of the spool, and the walls forming the pressure building chamber include the wall of the spool and the wall of the plug, the wall of the spool and the wall of the second valve seat. A sealing member is arranged between the plug and the second valve seat, and along the movement direction of the spool, the sealing member is closer to the pressure building chamber than the pressure relief channel.
[0012] As an optional solution, the pressure relief channel includes:
[0013] The first channel, at least part of the first channel is provided in the plug, and the first channel communicates with the first cavity;
[0014] The second channel, at least part of the second channel is provided in the second valve seat.
[0015] As an alternative, relative to the axial direction of the first valve seat, the first channel and / or the second channel are inclined.
[0016] As an alternative, the pressure relief channel further includes:
[0017] The third channel, along the radial direction of the first valve seat, the gap between the plug and the second valve seat forms the third channel;
[0018] The fourth channel, along the radial direction of the first valve seat, the gap between the first valve seat and the second valve seat forms the fourth channel;
[0019] The fifth channel, at least part of the fifth channel is provided in the second valve seat;
[0020] The sixth channel, the sixth channel is provided in the first valve seat, the sixth channel communicates with the liquid outlet, and the first channel, the third channel, the second channel, the fourth channel, the fifth channel and the sixth channel are communicated in sequence.
[0021] As an alternative, a groove is annularly provided on the outer wall surface of the plug, and along the radial direction of the first valve seat, the gap between the groove edge of the groove and the inner wall surface of the second valve seat forms a second cavity, and the second cavity is the third channel.
[0022] As an alternative, along the radial direction of the first valve seat, the gap between the outer wall surface of the second valve seat and the inner wall surface of the first valve seat forms a third cavity, and the third cavity is the fourth channel.
[0023] As an alternative, the fifth channel includes a first oil passage hole and a second oil passage hole that are communicated. The first oil passage hole and the second oil passage hole are respectively provided on the second valve seat. The first oil passage hole communicates with the fourth channel. The first oil passage hole extends along the radial direction of the first valve seat. The second oil passage hole communicates with the sixth channel. The second oil passage hole extends along the axial direction of the first valve seat so that the first oil passage hole is connected to the second oil passage hole.
[0024] As an alternative, the overflow valve further includes:
[0025] A tapered valve core, which is respectively slidably fitted in the first valve seat and the spool valve core, so that the tapered valve core opens or blocks the valve port in the first valve seat;
[0026] An elastic member is sleeved on the conical valve core, and one end of the elastic member abuts against the limiting platform of the conical valve core;
[0027] A base is slidably sleeved on the conical valve core. The other end of the elastic member abuts against the base, and the sliding valve core can abut against and push the base to move in a first direction to compress the elastic member. The first direction is the axial direction of the first valve seat and is the direction close to the valve port;
[0028] Wherein, along the radial direction of the first valve seat, a gap between the elastic member and the inner wall surface of the first valve seat forms a fourth chamber, and the fourth chamber is the sixth passage.
[0029] As an alternative, the sliding valve core includes a first wall and a second wall arranged opposite to each other. The sliding valve core has a first position and a second position. When the sliding valve core is in the first position, a fifth chamber is formed between the first wall and the second valve seat, and the second wall abuts against the plug; when the sliding valve core is in the second position, the first wall abuts against the second valve seat, and a sixth chamber is formed between the second wall and the plug;
[0030] A first damping hole and a seventh chamber which are communicated with each other are arranged in the conical valve core. The first damping hole is communicated with the liquid inlet on the first valve seat, and the seventh chamber is respectively communicated with the fifth chamber and the sixth chamber;
[0031] Wherein, along the radial direction of the first valve seat, a second damping hole is arranged on the sliding valve core, and the second damping hole communicates the fifth chamber with the seventh chamber; and a through hole is also arranged on the sliding valve core, and the through hole communicates the sixth chamber with the seventh chamber. At least part of the aperture of the second damping hole is smaller than the aperture of the through hole.
[0032] The beneficial effects of the present utility model are as follows:
[0033] By making at least part of the second valve seat located inside the first valve seat, part of the sliding valve core is slidably fitted with the second valve seat; meanwhile, making at least part of the plug arranged at one end of the second valve seat far away from the liquid outlet, part of the sliding valve core is slidably fitted with the plug, so that the plug and the sliding valve core can directly slide and cooperate; compared with the prior art, the piston sleeve and the plug are integrally formed into a structure, and there is no need to separately arrange the piston sleeve, reducing the number of parts, thereby being able to save costs; and making the sliding valve core and the plug directly slide and cooperate can improve the movement stability and reliability of the sliding valve core; moreover, a first chamber is formed between the sliding valve core and the plug, and the pressure relief passage is communicated with the first chamber and the liquid outlet, so that it is beneficial to discharge the oil liquid in the first chamber to the liquid outlet through the pressure relief passage, and the problem of overpressure of the oil liquid in the overflow valve can be avoided, ensuring that the oil liquid pressure in the overflow valve is relatively appropriate. Description of the Drawings
[0034] Figure 1 is a cross-sectional view of the overflow valve (the spool valve is in the first position) provided by the present utility model;
[0035] Figure 2 is Figure 1 a partial enlarged structural schematic diagram at position C in
[0036] Description of the reference numerals in the drawings:
[0037] 1 - first valve seat; 11 - liquid outlet; 12 - valve port; 13 - liquid inlet;
[0038] 2 - second valve seat; 3 - spool valve; 31 - first wall; 32 - second wall; 33 - fifth chamber; 34 - second damping hole; 35 - through hole; 36 - first chamber; 4 - plug;
[0039] 51 - first channel; 52 - third channel; 53 - second channel; 54 - fourth channel; 55 - fifth channel; 551 - first oil passage hole; 552 - second oil passage hole; 56 - sixth channel;
[0040] 6 - tapered spool valve; 61 - limiting platform; 62 - first damping hole; 63 - seventh chamber; 7 - elastic member; 8 - base; 9 - seal. Detailed implementation manners
[0041] All features disclosed in this specification, or all steps in the disclosed methods or processes, except for mutually exclusive features and / or steps, can be combined in any manner.
[0042] Any feature disclosed in this specification, unless specifically described, can be replaced by other equivalent or similar-purpose alternative features. That is, unless specifically described, each feature is only an example of a series of equivalent or similar features. Throughout the specification, the same reference numerals indicate the same elements.
[0043] 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 drawings and through specific implementation manners.
[0044] In this embodiment, an overflow valve is proposed. The overflow valve has a small number of components, can save costs, and can ensure high working stability and reliability of the overflow valve. At the same time, it can ensure that the oil pressure in the overflow valve is appropriate.
[0045] Specifically, as shown in Figure 1 and Figure 2As shown in the figure, the overflow valve includes a first valve seat 1, a second valve seat 2, a spool 3, a plug 4, and a pressure relief passage; wherein, a liquid outlet 11 is provided on the first valve seat 1; at least part of the second valve seat 2 is located inside the first valve seat 1, and part of the spool 3 is slidably fitted to the second valve seat 2; at least part of the plug 4 is provided at one end of the second valve seat 2 away from the liquid outlet 11, and part of the spool 3 is slidably fitted to the plug 4, and a first chamber 36 is formed between the spool 3 and the plug 4; at least part of the pressure relief passage is provided in the plug 4 and / or the second valve seat 2 and / or the first valve seat 1, and the pressure relief passage communicates the first chamber 36 with the liquid outlet 11.
[0046] In the overflow valve of this embodiment, compared with the prior art, the piston sleeve and the plug 4 are integrally formed into a structure; by making at least part of the second valve seat 2 located inside the first valve seat 1, part of the spool 3 is slidably fitted to the second valve seat 2; at the same time, by making at least part of the plug 4 provided at one end of the second valve seat 2 away from the liquid outlet 11, part of the spool 3 is slidably fitted to the plug 4, so that the plug 4 and the spool 3 can directly slide and cooperate; there is no need to separately provide a piston sleeve, reducing the number of components, thus being able to save costs; and, by directly sliding and cooperating the spool 3 and the plug 4, the action stability and reliability of the spool 3 can be improved; moreover, a first chamber 36 is provided in the spool 3, and the pressure relief passage communicates the first chamber 36 with the liquid outlet 11, so that it is beneficial to discharge the oil in the first chamber 36 to the liquid outlet 11 through the pressure relief passage, and the problem of pressure buildup due to excessive oil pressure in the overflow valve can be avoided, ensuring that the oil pressure in the overflow valve is relatively appropriate.
[0047] Further, as Figure 1 shown, a seal 9 is provided between the plug 4 and the second valve seat 2 to ensure the sealing effect between the plug 4 and the second valve seat 2 without setting a piston sleeve, so as to ensure good sealing performance even when only the plug 4 is provided. In this embodiment, the seal 9 can specifically be an O-ring.
[0048] Specifically, as Figure 1 shown, the overflow valve has a pressure building chamber for establishing pressure on both sides of the spool 3. The walls forming the pressure building chamber include the wall of the spool 3 and the wall of the plug 4, and the wall of the spool 3 and the wall of the second valve seat 2. Along the movement direction of the spool 3, the seal 9 is closer to the pressure building chamber relative to the pressure relief passage, that is, the seal 9 is located between the pressure relief passage and the pressure building chamber, so as to ensure a good sealing effect of the seal 9 on the pressure building chamber, thereby ensuring the pressure building effect of the pressure building chamber.
[0049] It should be noted that, as Figure 1 and Figure 2As shown, the two sides of the spool 3 refer to the two opposite sides of the spool 3, specifically referring to the first wall 31 and the second wall 32 mentioned in the following description; the pressure - building cavity includes two cavities located on both sides of the spool 3 respectively, specifically referring to the fifth cavity 33 and the sixth cavity mentioned in the following description; the movement direction of the spool 3 specifically refers to the directions of arrow A and arrow B as shown in Figure 1 in the figure.
[0050] Specifically, as shown in Figure 1 and Figure 2 the pressure - relief passage includes a first passage 51 and a second passage 53; among them, at least part of the first passage 51 is arranged in the plug 4, and the first passage 51 is communicated with the first cavity 36; at least part of the second passage 53 is arranged in the second valve seat 2.
[0051] Furthermore, as shown in Figure 1 and Figure 2 with respect to the axial direction of the first valve seat 1, the first passage 51 and / or the second passage 53 are inclined. On the one hand, it can better guide the flow of oil in the first passage 51 and / or the second passage 53, ensuring the smoothness and reliability of the oil flow in the entire pressure - relief passage; on the other hand, it can reduce the axial and radial layout dimensions of the first passage 51 and / or the second passage 53, making the layout of the entire pressure - relief passage more reasonable and compact. In this embodiment, the first passage 51 and the second passage 53 are respectively inclined.
[0052] Specifically, as shown in Figure 1 and Figure 2 the pressure - relief passage further includes a third passage 52, a fourth passage 54, a fifth passage 55 and a sixth passage 56. Along the radial direction of the first valve seat 1, the gap between the plug 4 and the second valve seat 2 forms the above - mentioned third passage 52; along the radial direction of the first valve seat 1, the gap between the first valve seat 1 and the second valve seat 2 forms the above - mentioned fourth passage 54; at least part of the fifth passage 55 is arranged in the second valve seat 2; the sixth passage 56 is arranged in the first valve seat 1, and the sixth passage 56 is communicated with the liquid outlet 11, and the first passage 51, the third passage 52, the second passage 53, the fourth passage 54, the fifth passage 55 and the sixth passage 56 are connected in sequence, so that the oil in the first cavity 36 passes through the first passage 51, the third passage 52, the second passage 53, the fourth passage 54, the fifth passage 55 and the sixth passage 56 to reach the liquid outlet 11 in sequence, and then flows back to the fuel tank through the liquid outlet 11.
[0053] Furthermore, as shown in Figure 1 and Figure 2 a groove is provided around the outer wall surface of the plug 4, and along the radial direction of the first valve seat 1, the gap between the edge of the groove and the inner wall surface of the second valve seat 2 forms the second cavity, and the second cavity is the above - mentioned third passage 52.
[0054] By forming a second chamber, the flow area of the third channel 52 is made larger, so that the oil in the first chamber 36 can be conveniently diverted to the second chamber through the first channel 51, thereby ensuring the smoothness and reliability of the oil in the first chamber 36 flowing into the third channel 52.
[0055] Specifically, as Figure 2 shown, along the radial direction of the first valve seat 1, the gap between the outer wall surface of the second valve seat 2 and the inner wall surface of the first valve seat 1 forms a third chamber, and the third chamber is the above-mentioned fourth channel 54; so that the flow area of the fourth channel 54 is larger, thereby facilitating the diversion of the oil in the second channel 53 into the third chamber, and ensuring the smoothness and reliability of the oil in the second channel 53 flowing into the fourth channel 54.
[0056] Further, as Figure 2 shown, the fifth channel 55 includes a first oil passage hole 551 and a second oil passage hole 552 that are connected. The first oil passage hole 551 and the second oil passage hole 552 are respectively provided on the second valve seat 2. The first oil passage hole 551 is communicated with the fourth channel 54, the first oil passage hole 551 extends along the radial direction of the first valve seat 1, the second oil passage hole 552 is communicated with the sixth channel 56, and the second oil passage hole 552 extends along the axial direction of the first valve seat 1, so that the first oil passage hole 551 is connected to the second oil passage hole 552.
[0057] Specifically, as Figure 1 and Figure 2 shown, the overflow valve further includes a conical valve core 6, an elastic member 7 and a base 8; wherein, the conical valve core 6 is respectively slidably fitted in the first valve seat 1 and the spool 3, so that the conical valve core 6 can open or block the valve port 12 in the first valve seat 1; the elastic member 7 is sleeved on the conical valve core 6, and one end of the elastic member 7 abuts against the limiting platform 61 of the conical valve core 6; the base 8 is slidably sleeved on the conical valve core 6, the other end of the elastic member 7 abuts against the base 8, and the spool 3 can abut against and push the base 8 to move in the first direction to compress the elastic member 7, so as to push the conical valve core 6 in the first direction through the elastic member 7. Among them, the elastic member 7 can specifically be a spring; the first direction is the axial direction of the first valve seat 1 and the direction close to the valve port 12, and the first direction is specifically as Figure 1 shown by the arrow A in
[0058] Further, as Figure 1 shown, along the radial direction of the first valve seat 1, the gap between the elastic member 7 and the inner wall surface of the first valve seat 1 forms a fourth chamber, and the fourth chamber is the above-mentioned sixth channel 56; so that the flow area of the sixth channel 56 is larger, thereby facilitating the diversion of the oil in the second oil passage hole 552 of the fifth channel 55 into the fourth chamber, and ensuring the smoothness and reliability of the oil in the fifth channel 55 flowing into the sixth channel 56.
[0059] That is, as Figure 1 and Figure 2 shown, the oil in the first chamber 36 can sequentially pass through the first passage 51, the second chamber, the second passage 53, the third chamber, the first oil passage hole 551, the second oil passage hole 552, the fourth chamber, and then flow back to the fuel tank through the liquid outlet 11, so as to relieve the pressure of the oil in the first chamber 36, ensure that the oil pressure in the entire overflow valve is relatively appropriate, and enable the discharge of the oil in the first chamber 36 to be relatively simple and convenient.
[0060] Further, as Figure 1 and Figure 2 shown, the spool valve 3 includes a first wall 31 and a second wall 32 arranged back to back, and the spool valve 3 has a first position and a second position; when the spool valve 3 is in the first position, a fifth chamber 33 is formed between the first wall 31 and the second valve seat 2, and the second wall 32 directly abuts against the plug 4; when the spool valve 3 is in the second position, the first wall 31 directly abuts against the second valve seat 2, and a sixth chamber is formed between the second wall 32 and the plug 4; and, a first damping hole 62 and a seventh chamber 63 are arranged in the conical valve core 6 and are connected to each other, the first damping hole 62 is connected to the liquid inlet 13 on the first valve seat 1, and the seventh chamber 63 is connected to the fifth chamber 33 and the sixth chamber respectively, so that the oil at the liquid inlet 13 can flow to the fifth chamber 33 and the sixth chamber respectively after passing through the first damping hole 62 and the seventh chamber 63, so that the oil in the fifth chamber 33 acts on the first wall 31, and the oil in the sixth chamber acts on the second wall 32; and, the acting area of the oil on the first wall 31 is smaller than the acting area of the oil on the second wall 32.
[0061] Specifically, as Figure 1 and Figure 2 shown, a second damping hole 34 is arranged on the spool valve 3 along the radial direction of the first valve seat 1, and the second damping hole 34 connects the fifth chamber 33 and the seventh chamber 63; and a through hole 35 is also arranged on the spool valve 3, and the through hole 35 connects the sixth chamber and the seventh chamber 63, and at least part of the aperture of the second damping hole 34 is smaller than the aperture of the through hole 35, so as to ensure the throttling and pressure reducing effect of the second damping hole 34.
[0062] By arranging the second damping hole 34 on a part of the spool valve 3 along the radial direction of the first valve seat 1, the second damping hole 34 can be directly connected to the fifth chamber 33, so as to ensure the stable pressurization in the fifth chamber 33, and thus enable the buffer effect of the entire overflow valve to be better.
[0063] The specific working process of the overflow valve in this embodiment is as follows:
[0064] First, the pressure of the oil fluid at the liquid inlet 13 acts on the first wall surface of the conical valve core 6 close to the valve port 12, enabling the oil fluid to enter the seventh chamber 63 through the first damping hole 62, so that the oil fluid in the seventh chamber 63 acts on the second wall surface of the conical valve core 6 away from the valve port 12. At this time, since the acting force on the first wall surface is greater than the acting force on the second wall surface, the conical valve core 6 can be pushed to move in the second direction to compress the elastic member 7, thereby instantaneously opening the valve port 12. Among them, the second direction is opposite to the first direction, and the second direction is specifically as shown by the arrow B in Figure 1 as shown.
[0065] Then, the oil fluid in the seventh chamber 63 flows to the fifth chamber 33 through the second damping hole 34, so that the oil fluid in the fifth chamber 33 acts on the first wall 31 of the spool valve 3; at the same time, the oil fluid in the seventh chamber 63 flows to the sixth chamber through the through hole 35, so that the oil fluid in the sixth chamber acts on the second wall 32 of the spool valve 3; since the acting area of the oil fluid on the first wall 31 is smaller than the acting area of the oil fluid on the second wall 32, the spool valve 3 moves in the first direction to compress the elastic member 7, thereby enabling the elastic member 7 to push the conical valve core 6 to move in the first direction to re-close the valve port 12.
[0066] Finally, when the spool valve 3 moves until the first wall 31 abuts against the second valve seat 2, the spool valve 3 cannot continue to move in the first direction. At this time, the pressure of the overflow valve is established stably; when the pressure of the oil fluid at the liquid inlet 13 increases to be able to push the conical valve core 6 in the second direction, the conical valve core 6 moves in the second direction to re-open the valve port 12 to start the overflow operation.
[0067] Among them, during the above working process, there may be oil fluid leaking from the mating gaps between the spool valve 3 and the second valve seat 2, and / or between the spool valve 3 and the plug 4, and / or between the plug 4 and the second valve seat 2 in the first chamber 36, and the oil fluid in the first chamber 36 flows back to the fuel tank through the first channel 51, the second chamber, the second channel 53, the third chamber, the first oil passing hole 551, the second oil passing hole 552, the fourth chamber and then through the liquid outlet 11 in sequence.
[0068] In the overflow valve of this embodiment, by slidingly mating between the plug 4 and the spool valve 3 and separately providing a structure of the plug 4 alone, the piston sleeve in the prior art is omitted, the number of parts is reduced, and the cost is saved; and, by providing the above pressure relief channel, the pressure relief discharge of the oil fluid in the first chamber 36 can be made more convenient and smooth.
[0069] The above content is only the preferred embodiment of the present invention. For those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. The content of this specification should not be construed as a limitation to the present invention.
Claims
1. An overflow valve, characterized in that, Comprising: A first valve seat (1) provided with a liquid outlet (11); A second valve seat (2) and a sliding valve core (3), at least part of the second valve seat (2) is located within the first valve seat (1), and part of the sliding valve core (3) is slidably engaged with the second valve seat (2); A plug (4), at least part of the plug (4) is provided at one end of the second valve seat (2) away from the liquid outlet (11), part of the sliding valve core (3) is slidably engaged with the plug (4), and a first chamber (36) is formed between the sliding valve core (3) and the plug (4); A pressure relief passage, at least part of the pressure relief passage is provided in the plug (4) and / or the second valve seat (2) and / or the first valve seat (1), and the pressure relief passage communicates the first chamber (36) with the liquid outlet (11).
2. The overflow valve according to claim 1, characterized in that, The overflow valve has a pressure building chamber for establishing pressure on both sides of the sliding valve core (3), and the walls forming the pressure building chamber include the wall of the sliding valve core (3) and the wall of the plug (4), the wall of the sliding valve core (3) and the wall of the second valve seat (2). A seal (9) is provided between the plug (4) and the second valve seat (2). Along the movement direction of the sliding valve core (3), the seal (9) is closer to the pressure building chamber relative to the pressure relief passage.
3. The overflow valve according to claim 1 or 2, characterized in that The pressure relief passage includes: A first passage (51), at least part of the first passage (51) is provided in the plug (4), and the first passage (51) communicates with the first chamber (36); A second passage (53), at least part of the second passage (53) is provided in the second valve seat (2).
4. The overflow valve according to claim 3, characterized in that, Relative to the axial direction of the first valve seat (1), the first passage (51) and / or the second passage (53) is inclined.
5. The overflow valve according to claim 3, characterized in that, The pressure relief passage further includes: A third passage (52), along the radial direction of the first valve seat (1), the gap between the plug (4) and the second valve seat (2) forms the third passage (52); A fourth passage (54), along the radial direction of the first valve seat (1), the gap between the first valve seat (1) and the second valve seat (2) forms the fourth passage (54); A fifth passage (55), at least part of the fifth passage (55) is provided in the second valve seat (2); A sixth passage (56), the sixth passage (56) is provided in the first valve seat (1), the sixth passage (56) communicates with the liquid outlet (11), and the first passage (51), the third passage (52), the second passage (53), the fourth passage (54), the fifth passage (55) and the sixth passage (56) are sequentially communicated.
6. The overflow valve according to claim 5, characterized in that, A groove is provided in a circumferential manner on the outer wall surface of the plug (4). Along the radial direction of the first valve seat (1), the gap between the edge of the groove and the inner wall surface of the second valve seat (2) forms a second chamber, and the second chamber is the third passage (52).
7. The overflow valve according to claim 5, characterized in that Radially along the first valve seat (1), a gap between the outer wall surface of the second valve seat (2) and the inner wall surface of the first valve seat (1) forms a third chamber, and the third chamber is the fourth passage (54).
8. The overflow valve according to any one of claims 5 to 7, characterized in that, The fifth passage (55) includes a first oil passage hole (551) and a second oil passage hole (552) that are communicated. The first oil passage hole (551) and the second oil passage hole (552) are respectively arranged on the second valve seat (2). The first oil passage hole (551) is communicated with the fourth passage (54), the first oil passage hole (551) extends radially along the first valve seat (1), the second oil passage hole (552) is communicated with the sixth passage (56), and the second oil passage hole (552) extends axially along the first valve seat (1) so that the first oil passage hole (551) is connected to the second oil passage hole (552).
9. The overflow valve according to any one of claims 5-7, characterized in that, The overflow valve further includes: A conical valve core (6), which is respectively slidably fitted in the first valve seat (1) and the spool valve core (3), so that the conical valve core (6) opens or blocks the valve port (12) in the first valve seat (1); An elastic member (7), sleeved on the conical valve core (6), and one end of the elastic member (7) abuts against the limiting platform (61) of the conical valve core (6); A base (8), slidably sleeved on the conical valve core (6), the other end of the elastic member (7) abuts against the base (8), and the spool valve core (3) can abut against and push the base (8) to move in a first direction to compress the elastic member (7), and the first direction is the axial direction of the first valve seat (1) and is the direction close to the valve port (12); Wherein, radially along the first valve seat (1), a gap between the elastic member (7) and the inner wall surface of the first valve seat (1) forms a fourth chamber, and the fourth chamber is the sixth passage (56).
10. The overflow valve according to claim 9, characterized in that, The spool valve core (3) includes a first wall (31) and a second wall (32) arranged opposite to each other. The spool valve core (3) has a first position and a second position. When the spool valve core (3) is in the first position, a fifth chamber (33) is formed between the first wall (31) and the second valve seat (2), and the second wall (32) abuts against the plug (4); when the spool valve core (3) is in the second position, the first wall (31) abuts against the second valve seat (2), and a sixth chamber is formed between the second wall (32) and the plug (4); A first damping hole (62) and a seventh chamber (63) that are communicated are arranged in the conical valve core (6). The first damping hole (62) is communicated with the liquid inlet (13) on the first valve seat (1), and the seventh chamber (63) is respectively communicated with the fifth chamber (33) and the sixth chamber; Wherein, along the radial direction of the first valve seat (1), a second damping hole (34) is provided on the spool (3), and the second damping hole (34) communicates the fifth chamber (33) with the seventh chamber (63); and a through hole (35) is further provided on the spool (3), the through hole (35) communicates the sixth chamber with the seventh chamber (63), and the aperture of at least part of the second damping hole (34) is smaller than the aperture of the through hole (35).