Electro-hydraulic reversing valve

Abstract

The utility model discloses an electro-hydraulic reversing valve which comprises a pilot electromagnetic valve and a main valve. The pilot electromagnetic valve is detachably connected with the main valve; after the pilot electromagnetic valve is connected with the main valve, an oil cavity in the pilot electromagnetic valve is communicated with an oil way in the main valve; a first pilot control oil way, a second pilot control oil way, an outer oil supply way, an inner oil supply way, an outer oil discharge way and an inner oil discharge way in the main valve are all casting oil ways, and the number of each oil port is two. The oil paths in the main valve are all formed through casting instead of auxiliary holes, so that the impact resistance of the oil paths can be improved, oil leakage at conical plugs of the auxiliary holes is avoided, the pressure loss of hydraulic oil flowing in the oil paths can be reduced, and the through-flow capacity of the hydraulic oil in the oil paths is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to a reversing valve technical field, concretely relates to a kind of electro-hydraulic reversing valve. BACKGROUND

[0002] Electro-hydraulic reversing valve is suitable for large flow occasions, such as shotcreting machine equipment, metallurgical equipment etc., therefore, hydraulic oil is greatly impacted on the inside of electro-hydraulic reversing valve, resulting in that after using for a certain time, the end cover of electro-hydraulic reversing valve and the combination of main valve body and process hole cone plug are prone to oil leakage.

[0003] Although various solutions are proposed for oil leakage problem at present, such as: increasing damping in the oil inlet cavity of pilot solenoid valve, superimposing reversing time regulator to throttle control cavity to reduce impact, superimposing direct-acting pressure reducing valve to reduce control pressure to reduce impact, etc., but the effect of reducing impact is limited, and part of the measures will also cause hydraulic oil reversing speed to drop when reducing impact, which cannot meet the user's use requirements.

[0004] Based on this, how to provide a kind of electro-hydraulic reversing valve that can effectively avoid oil leakage at the combination of end cover and main valve body and process hole cone plug becomes a technical problem to be solved urgently. SUMMARY

[0005] The utility model provides a kind of electro-hydraulic reversing valve, to solve the problem that the existing electro-hydraulic reversing valve is prone to oil leakage at the combination of end cover and main valve body and process hole cone plug.

[0006] To solve the above technical problem, a kind of electro-hydraulic reversing valve is provided by the utility model, comprising:

[0007] Pilot solenoid valve and main valve;The pilot solenoid valve and the main valve are detachably connected;

[0008] The pilot solenoid valve has oil inlet cavity, oil return cavity, first working oil cavity and second working oil cavity;

[0009] The main valve is provided with first pilot control oil way, second pilot control oil way, external oil supply path, internal oil supply path, external oil discharge path and internal oil discharge path;

[0010] After the pilot solenoid valve is connected with the main valve, the first working oil cavity is communicated with the first pilot control oil way, the second working oil cavity is communicated with the second pilot control oil way, the oil inlet cavity is communicated with the external oil supply path, the oil inlet cavity is communicated with the internal oil supply path, the oil return cavity is communicated with the internal oil discharge path, and the oil return cavity is communicated with the external oil discharge path;

[0011] The first pilot control oil way, the second pilot control oil way, the external oil supply path, the internal oil supply path, the external oil discharge path and the internal oil discharge path are all cast oil paths.

[0012] The oil ports of the first pilot control oil path, the second pilot control oil path, the outer supply oil path, the inner supply oil path, the outer discharge oil path and the inner discharge oil path are all two.

[0013] According to an embodiment of the present application, the main valve comprises a main valve core and a main valve body; a valve core hole for accommodating the main valve core is arranged inside the main valve body.

[0014] According to an embodiment of the present application, detachable screw plugs for preventing hydraulic oil from flowing out from both sides of the main valve body are connected to both sides of the main valve body; the screw plugs and the main valve body are connected through threads.

[0015] According to an embodiment of the present application, the screw plug is an internal hexagonal screw plug.

[0016] According to an embodiment of the present application, knurling is arranged on the contact surface of the head of the screw plug and the side wall of the main valve body.

[0017] According to an embodiment of the present application, a sealing groove is arranged on the head of the screw plug; an elastomer diaphragm sealing ring is embedded in the sealing groove; the elastomer diaphragm sealing ring is located in the knurling inner circle.

[0018] According to an embodiment of the present application, a first taper plug is detachably arranged in the inner supply oil path; the first taper plug is used to prevent hydraulic oil from flowing through the inner supply oil path.

[0019] According to an embodiment of the present application, a second taper plug is detachably arranged in the inner discharge oil path; the second taper plug is used to prevent hydraulic oil from flowing through the inner discharge oil path.

[0020] According to an embodiment of the present application, the main valve further comprises a first reset spring, a second reset spring, a first spring cavity and a second spring cavity; after the screw plug is connected to the main valve body, the first spring cavity and the second spring cavity are respectively formed on both sides of the main valve core; the first reset spring is arranged in the first spring cavity; the second reset spring is arranged in the second spring cavity; one end of the first reset spring is in contact with the main valve core, and the other end is in contact with the screw plug; one end of the second reset spring is in contact with the main valve core, and the other end is in contact with the screw plug.

[0021] The utility model discloses at least one embodiment can reach following beneficial effect: in the utility model, the first pilot control oil circuit in main valve, second pilot control oil circuit, outside oil supply path, inside oil supply path, outside oil discharge path and inside oil discharge path are all cast oil circuit, and all only have two oil ports, thereby need no longer through the mode of the process hole to form these oil paths, also need no longer utilize the process hole cone to block up the other oil ports except the oil inlet and oil outlet on the oil path, thereby not only be favorable to the promotion oil path's shock resistance, avoid in the process hole cone place oil leakage, can also reduce the pressure loss of hydraulic oil flowing in the oil path, be favorable to the promotion hydraulic oil's through flow capacity in the oil path.

[0022] In addition, the utility model discloses using the screw plug instead of the end cover to prevent hydraulic oil from flowing out from both sides of the main valve body, since the screw plug is connected with the main valve body through threads, the sealing performance is better, thereby effectively reducing the oil leakage from both sides of the main valve body, and the shock resistance of both sides of the main valve body is improved. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or the prior art description, and obviously, the drawings in the following description are only some embodiments in the utility model, and for those skilled in the art, other drawings can also be obtained according to these drawings without creative labor.

[0024] Figure 1 It is the structure schematic diagram of electro-hydraulic reversing valve provided according to one embodiment of the utility model;

[0025] Figure 2 It is the axial side schematic diagram of screw plug of electro-hydraulic reversing valve provided according to one embodiment of the utility model;

[0026] Figure 3 It is the structure schematic diagram of electro-hydraulic reversing valve provided according to one embodiment of the utility model; Figure 2 The front view of screw plug shown in;

[0027] Figure 4 It is the left view of screw plug shown in according to one embodiment of the utility model; Figure 2

[0028] Reference signs:

[0029] 1, pilot solenoid valve;11, oil inlet cavity;12, oil return cavity;13, first working oil cavity;14, second working oil cavity;15, pilot valve core;16, first electromagnet assembly;17, second electromagnet assembly;

[0030] ​2, main valve; 21, main valve body; 211, first pilot control oil passage; 212, second pilot control oil passage; 213, outer supply oil passage; 214, inner supply oil passage; 215, outer drain oil passage; 216, inner drain oil passage; 217, first taper plug; 218, second taper plug; 22, main valve core; 23, first return spring; 24, second return spring; 25, first spring cavity; 26, second spring cavity; 27, screw plug; 271, head of screw plug; 272, knurl; 273, sealing groove; 274, thread; 275, elastomer diaphragm seal. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of one or more embodiments of the present application more clear, the technical scheme of one or more embodiments of the present application will be described clearly and completely below in combination with specific embodiments of the present application and corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of one or more embodiments of the present application.

[0032] The existing electro-hydraulic reversing valve usually contains many process holes and process hole taper plugs, because the oil passage in the existing electro-hydraulic reversing valve is not integrally cast with the main valve body, but is obtained by punching process holes on the main valve body. However, the oil passage obtained by this method will have other oil ports in addition to the oil inlet and oil outlet. In order to prevent hydraulic oil from flowing out of these other oil ports, process hole taper plugs need to be arranged at these other oil ports to block these oil ports. In actual application, due to the large impact of hydraulic oil on the internal part of the electro-hydraulic reversing valve, the process hole taper plugs of the electro-hydraulic reversing valve are prone to oil leakage after a certain period of use.

[0033] Moreover, the existing electro-hydraulic reversing valve uses an end cover to prevent hydraulic oil from flowing out from both sides of the main valve body. The end cover and the main valve body are connected by bolts, and the sealing performance is poor, so hydraulic oil is easy to leak from the connection between the end cover and the main valve body.

[0034] In an embodiment of the present application, the first pilot control oil passage, the second pilot control oil passage, the outer supply oil passage, the inner supply oil passage, the outer drain oil passage and the inner drain oil passage in the main valve all adopt cast oil passages with only two oil ports, so that these oil passages do not need to be formed by punching process holes, and the other oil ports on the oil passages in addition to the oil inlet and the oil outlet do not need to be blocked by process hole taper plugs, thereby solving the technical problem that the electro-hydraulic reversing valve in the prior art is prone to oil leakage at the process hole taper plugs.

[0035] And, in another embodiment of the present application, the threaded nut is used instead of the end cover to prevent hydraulic oil from flowing out from both sides of the main valve body, since the threaded nut is connected with the main valve body by threads, the sealing is better, and the oil leakage from both sides of the main valve body can be effectively reduced, thereby solving the technical problem of the existing electro-hydraulic directional valve that is prone to oil leakage at the joint between the end cover and the main valve body.

[0036] The technical solutions provided by the embodiments of the present application are described in detail below with reference to the drawings.

[0037] Figure 1 is a structural schematic diagram of an electro-hydraulic directional valve according to an embodiment of the present application. Figure 1 As shown in the figure, the electro-hydraulic directional valve provided by the present application comprises a pilot electromagnetic valve 1 and a main valve 2; the pilot electromagnetic valve 1 and the main valve 2 are detachably connected.

[0038] Among them, the pilot electromagnetic valve 1 has an oil inlet cavity 11, an oil return cavity 12, a first working oil cavity 13 and a second working oil cavity 14; the main valve 2 is provided with a first pilot control oil way 211, a second pilot control oil way 212, an external oil supply way 213, an internal oil supply way 214, an external oil discharge way 215 and an internal oil discharge way 216.

[0039] After the pilot electromagnetic valve 1 is connected with the main valve 2, the first working oil cavity 13 is communicated with the first pilot control oil way 211, the second working oil cavity 14 is communicated with the second pilot control oil way 212, the oil inlet cavity 11 is communicated with the external oil supply way 213, the oil inlet cavity 11 is communicated with the internal oil supply way 214, the oil return cavity 12 is communicated with the internal oil discharge way 216, and the oil return cavity 12 is communicated with the external oil discharge way 215.

[0040] Among them, the first pilot control oil way 211, the second pilot control oil way 212, the external oil supply way 213, the internal oil supply way 214, the external oil discharge way 215 and the internal oil discharge way 216 are all cast oil ways; and the oil ports of the first pilot control oil way 211, the second pilot control oil way 212, the external oil supply way 213, the internal oil supply way 214, the external oil discharge way 215 and the internal oil discharge way 216 are all two.

[0041] In the embodiment of the utility model, the first pilot control oil path 211, the second pilot control oil path 212, the outer supply oil path 213, the inner supply oil path 214, the outer discharge oil path 215 and the inner discharge oil path 216 in the main valve 2 are all cast oil paths integrally formed with the main valve body 21, and these oil paths do not contain other oil ports except the oil inlet and the oil outlet, so that these oil paths do not need to be formed by means of punching process holes, and other oil ports on the oil paths except the oil inlet and the oil outlet do not need to be blocked by process hole plugs, which not only helps to improve the impact resistance of the oil paths in the main valve 2 and avoid oil leakage at the process hole plugs, but also reduces the pressure loss of the hydraulic oil flowing in the oil paths and helps to improve the flow capacity of the hydraulic oil in the oil paths.

[0042] In one embodiment of the utility model, the main valve 2 can include a main valve core 22 and a main valve body 21; the main valve body 21 can be internally provided with a valve core hole for accommodating the main valve core 22.

[0043] Specifically, the first pilot control oil path 211, the second pilot control oil path 212, the outer supply oil path 213, the inner supply oil path 214, the outer discharge oil path 215 and the inner discharge oil path 216 are all located in the main valve body 21. The main valve core 22 is located in the valve core hole of the main valve body 21 and can move back and forth along the axial direction of the valve core hole.

[0044] In one embodiment of the utility model, the main valve body 21 is detachably connected on both sides with a screw plug 27 for preventing hydraulic oil from flowing out from both sides of the main valve body 21; the screw plug 27 is connected with the main valve body 21 through threads.

[0045] Unlike the existing electro-hydraulic reversing valve that uses an end cover to prevent hydraulic oil from flowing out from both sides of the main valve body, the utility model uses a screw plug to replace the end cover to prevent hydraulic oil from flowing out from both sides of the main valve body. Since the screw plug is connected with the main valve body through threads, the sealing performance is better, so that the occurrence of oil leakage from both sides of the main valve body can be effectively reduced, and the impact resistance of both sides of the main valve body can also be improved.

[0046] Figure 2 is the axial side view of the screw plug of the electro-hydraulic reversing valve according to one embodiment of the utility model. Figure 3 is the axial side view of the screw plug of the electro-hydraulic reversing valve according to one embodiment of the utility model. Figure 2 is the front view of the screw plug shown in Figure 2 and Figure 3 As shown in the embodiment of the utility model, the contact surface of the head 271 of the screw plug 27 in contact with the side wall of the main valve body 21 is provided with knurling 272.

[0047] The contact surface between the plug's head 271 and the sidewall of the main valve body 21 is an annular surface. Knurling 272 is provided on this annular surface to increase friction between the plug's head 271 and the sidewall of the main valve body 21, effectively preventing the plug from loosening. The knurling 272 can be either straight or cross-linked, without specific limitation.

[0048] In one embodiment of the present invention, a sealing groove 273 may be provided on the head 271 of the screw plug; an elastomeric diaphragm (ED) sealing ring 275 may be embedded in the sealing groove 273 ; and the elastomeric diaphragm sealing ring 275 is located on the inner ring of the knurling 272 .

[0049] ED sealing rings are commonly used industrial seals, used as specialized seals for pneumatic and hydraulic joints such as pipe joints, hydraulic plugs, and transition joints. They offer superior sealing performance compared to traditional O-rings. The present invention further enhances the sealing performance of the screw plug 27 by embedding an elastomeric diaphragm sealing ring 275 within the contact surface between the screw plug's head 271 and the sidewall of the main valve body 21, effectively preventing hydraulic oil leakage from the contact area between the screw plug 27 and the sidewall of the main valve body 21.

[0050] In one embodiment of the present invention, the screw plugs 27 for preventing the hydraulic oil from flowing out from both sides of the main valve body 21 may be hexagon socket screw plugs. Figure 4 According to an embodiment of the present invention, Figure 2 The left side view of the screw plug is shown in the figure. Figure 4 and Figure 3 As shown, a hexagonal recess is provided at the head of the screw plug 27 , so that the user can use a hexagonal wrench to install the screw plug 27 on the main valve 2 or remove the screw plug 27 from the main valve 2 .

[0051] In one embodiment of the present invention, a first cone plug 217 is detachably provided in the internal oil supply passage 214; the first cone plug 217 is used to prevent the hydraulic oil from flowing in the internal oil supply passage 214. Figure 1 As shown, the internal oil supply path 214 is an oil path from the oil inlet P of the main valve 2 to the oil inlet chamber 11 of the pilot solenoid valve 1. After the hydraulic oil enters the oil inlet P of the main valve 2, it can reach the oil inlet chamber 11 through the internal oil supply path 214, thereby realizing the internal oil supply of the pilot solenoid valve 1.

[0052] The external oil supply line 213 is an oil line from the oil inlet X of the main valve 2 to the oil inlet chamber 11 of the pilot solenoid valve 1. After the hydraulic oil enters the oil inlet X of the main valve 2, it can reach the oil inlet chamber 11 through the external oil supply line 213, thereby realizing external oil supply to the pilot solenoid valve 1.

[0053] In actual applications, the pilot solenoid valve 1 can only be supplied with oil internally or externally; it cannot be supplied both internally and externally simultaneously. When the first cone plug 217 is installed in the internal oil supply passage 214, hydraulic oil cannot flow within the internal oil supply passage 214. In this case, oil can be supplied from the oil inlet X of the main valve 2, achieving external oil supply to the pilot solenoid valve 1. When the first cone plug 217 is not installed in the internal oil supply passage 214, hydraulic oil can flow within the internal oil supply passage 214. After blocking the oil inlet X of the main valve 2, oil can be supplied from the oil inlet P of the main valve 2, achieving internal oil supply to the pilot solenoid valve 1.

[0054] In one embodiment of the present invention, a second cone plug 218 is detachably provided in the inner oil discharge passage 216; the second cone plug 218 is used to prevent the hydraulic oil from flowing in the inner oil discharge passage 216. Figure 1 As shown, internal oil drain path 216 is an oil path from the oil return port T of main valve 2 to the oil return chamber 12 of pilot solenoid valve 1. Hydraulic oil can flow from the oil return chamber 12 of pilot solenoid valve 1 through internal oil drain path 216 to the oil return port T of main valve 2, and then further flow back to the oil tank, thus draining the internal oil of pilot solenoid valve 1.

[0055] External oil discharge path 215 runs from the oil return port Y of main valve 2 to the oil return chamber 12 of pilot solenoid valve 1. Hydraulic oil can flow from the oil return chamber 12 of pilot solenoid valve 1 through external oil discharge path 215 to the oil return port Y of main valve 2, and then back to the oil tank, thus draining the pilot solenoid valve 1 externally.

[0056] In actual applications, the pilot solenoid valve 1 can only be drained internally or externally; it cannot be drained both internally and externally simultaneously. When the second cone plug 218 is installed in the internal drain oil passage 216, the hydraulic oil cannot flow within the internal drain oil passage 216. In this case, the oil can be drained through the oil return port Y of the main valve 2, achieving external drain of the pilot solenoid valve 1. When the second cone plug 218 is not installed in the internal drain oil passage 216, the hydraulic oil can flow within the internal drain oil passage 216. After blocking the oil return port Y of the main valve 2, the oil can be drained through the oil return port T of the main valve 2, achieving internal drain of the pilot solenoid valve 1.

[0057] like Figure 1 As shown, in one embodiment of the present utility model, the main valve 2 also includes a first return spring 23, a second return spring 24, a first spring chamber 25 and a second spring chamber 26; after the screw plug 27 is connected to the main valve body 21, a first spring chamber 25 and a second spring chamber 26 are respectively formed on both sides of the main valve core 22; the first return spring 23 is arranged in the first spring chamber 25; the second return spring 24 is arranged in the second spring chamber 26; one end of the first return spring 23 contacts the main valve core 22, and the other end contacts the screw plug 27; one end of the second return spring 24 contacts the main valve core 22, and the other end contacts the screw plug 27.

[0058] Specifically, the pilot electromagnetic valve 1 further comprises a pilot spool 15, a first electromagnet assembly 16 and a second electromagnet assembly 17.

[0059] In actual application, the two sides of the pilot spool 15 also contact with reset springs, and under the condition that the first electromagnet assembly 16 and the second electromagnet assembly 17 are not powered, the pilot spool 15 is located at the initial position in the center under the action of the two sides of the reset springs, and the main spool 22 is also located at the initial position in the center under the action of the two sides of the reset springs. When the pilot electromagnetic valve 1 is supplied with oil, internal oil supply (hydraulic oil enters from the oil inlet P of the main valve 2, and reaches the oil inlet cavity 11 of the pilot electromagnetic valve 1 through the internal oil supply path 214) or external oil supply (hydraulic oil enters from the oil inlet X of the main valve 2, and reaches the oil inlet cavity 11 of the pilot electromagnetic valve 1 through the external oil supply path 213) can be adopted.

[0060] After the pilot electromagnetic valve 1 is supplied with oil, the oil inlet cavity 11 is filled with hydraulic oil, and under the condition that the first electromagnet assembly 16 and the second electromagnet assembly 17 are not powered, the pilot spool 15 is still at the initial position, and the oil inlet cavity 11 is not connected with the first working oil cavity 13 and the second working oil cavity 14 in the pilot electromagnetic valve 1.

[0061] At this time, if the second electromagnet assembly 17 is powered, the second electromagnet assembly 17 will push the pilot spool 15 to move in the direction of the first electromagnet assembly 16, and after moving, the oil inlet cavity 11 is connected with the first working oil cavity 13, and the second working oil cavity 14 is connected with the oil return cavity 12. Hydraulic oil flows from the oil inlet cavity 11 into the first working oil cavity 13 under the action of oil pressure, and then flows from the first working oil cavity 13 into the first spring cavity 25 through the first pilot control oil path 211. When the first spring cavity 25 is filled with hydraulic oil, the hydraulic oil pushes the main spool 22 to move in the direction of the second spring cavity 26, and after moving, the hydraulic oil in the second spring cavity 26 is extruded and can flow from the second spring cavity 26 into the second working oil cavity 14 through the second pilot control oil path 212, and then flow from the second working oil cavity 14 into the oil return cavity 12, and then flow back into the oil tank through internal oil discharge or external oil discharge. At this time, since the main spool 22 moves in the direction of the second spring cavity 26, the oil inlet P of the main valve 2 is connected with the working oil outlet B, and the working oil outlet A is connected with the oil return outlet T. After the power supply to the second electromagnet assembly 17 is turned off, the pilot spool 15 and the main spool 22 will return to the initial positions under the action of the two sides of the reset springs.

[0062] When the first electromagnet assembly 16 is powered again, the first electromagnet assembly 16 is powered and the pilot valve core 15 is pushed to move in the direction of the second electromagnet assembly 17, after moving, the oil inlet cavity 11 is communicated with the second working oil cavity 14, and the first working oil cavity 13 is communicated with the oil return cavity 12. Hydraulic oil flows from the oil inlet cavity 11 into the second working oil cavity 14 under the action of oil pressure, and then flows from the second working oil cavity 14 into the second spring cavity 26 through the second pilot control oil way 212. When the second spring cavity 26 is filled with hydraulic oil, the hydraulic oil pushes the main valve core 22 to move in the direction of the first spring cavity 25, after moving, the hydraulic oil in the first spring cavity 25 is extruded and can flow from the first spring cavity 25 into the first working oil cavity 13 through the first pilot control oil way 211, and then flows from the first working oil cavity 13 into the oil return cavity 12, and then flows back into the oil tank through the internal oil discharge or external oil discharge. At this time, since the main valve core 22 moves in the direction of the first spring cavity 25, the oil inlet P of the main valve 2 is communicated with the working oil port A, and the working oil port B is communicated with the oil return port T. After the power supply of the first electromagnet assembly 16 is turned off, the pilot valve core 15 and the main valve core 22 all return to the initial positions under the action of the reset springs on both sides.

[0063] In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more than two; the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail" and the like indicate the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore it cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" and the like are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0064] In the description of the present application, it should be pointed out that, unless otherwise specified and limited, the terms "connected", "connected" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium. For ordinary skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0065] Although the present subject matter has been described in specific structural features and / or method logical action specific language, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are merely example forms of implementing the claims.

[0066] It should be explained that the above is only the preferred embodiment of the present application, and is not used to limit the present application, and for the skilled in the art, the present application can have various changes and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application, are included in the scope of the claims of the present application.

Claims

1. An electro-hydraulic reversing valve, characterized in that: The electro-hydraulic reversing valve comprises: A pilot solenoid valve and a main valve; the pilot solenoid valve and the main valve are detachably connected; The pilot solenoid valve has an oil inlet chamber, an oil return chamber, a first working oil chamber and a second working oil chamber; The main valve is provided with a first pilot control oil circuit, a second pilot control oil circuit, an external oil supply circuit, an internal oil supply circuit, an external oil discharge circuit and an internal oil discharge circuit; After the pilot solenoid valve is connected to the main valve, the first working oil chamber is communicated with the first pilot control oil circuit, the second working oil chamber is communicated with the second pilot control oil circuit, the oil inlet chamber is communicated with the external oil supply circuit, the oil inlet chamber is communicated with the internal oil supply circuit, the oil return chamber is communicated with the internal oil discharge circuit, and the oil return chamber is communicated with the external oil discharge circuit; The first pilot control oil circuit, the second pilot control oil circuit, the external oil supply circuit, the internal oil supply circuit, the external oil exhaust circuit, and the internal oil exhaust circuit are all cast oil circuits integrally formed with the main valve body of the main valve; The first pilot control oil circuit, the second pilot control oil circuit, the external oil supply circuit, the internal oil supply circuit, the external oil discharge circuit, and the internal oil discharge circuit each have two oil ports; Screw plugs for preventing hydraulic oil from flowing out of the two sides of the main valve body are detachably connected to both sides of the main valve body of the main valve; the screw plugs are connected to the main valve body via threads.

2. The electro-hydraulic directional control valve according to claim 1, characterized in that: The main valve comprises a main valve core and a main valve body; a valve core hole for accommodating the main valve core is provided inside the main valve body.

3. The electro-hydraulic directional control valve according to claim 1, characterized in that: The screw plug is a hexagonal screw plug.

4. The electro-hydraulic directional control valve according to claim 1, characterized in that: Knurling is provided on the contact surface between the head of the screw plug and the side wall of the main valve body.

5. The electro-hydraulic directional control valve according to claim 4, characterized in that: A sealing groove is provided on the head of the screw plug; an elastic diaphragm sealing ring is embedded in the sealing groove; and the elastic diaphragm sealing ring is located on the knurled inner ring.

6. The electro-hydraulic directional control valve according to claim 1, characterized in that: A first cone plug is detachably provided in the internal oil supply passage; the first cone plug is used to prevent hydraulic oil from flowing in the internal oil supply passage.

7. The electro-hydraulic directional control valve according to claim 1, characterized in that: A second cone plug is detachably provided in the inner oil discharge passage; the second cone plug is used to prevent the hydraulic oil from flowing in the inner oil discharge passage.

8. The electro-hydraulic directional control valve according to claim 2, characterized in that: The main valve further includes a first return spring, a second return spring, a first spring chamber, and a second spring chamber. After the screw plug is connected to the main valve body, the first spring chamber and the second spring chamber are formed on both sides of the main valve core respectively. The first return spring is disposed in the first spring chamber; the second return spring is disposed in the second spring chamber. One end of the first return spring contacts the main valve core, and the other end contacts the screw plug. One end of the second return spring contacts the main valve core, and the other end contacts the screw plug.

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