Back pressure balanced solenoid valve

Abstract

The utility model discloses a back pressure balanced solenoid valve relates to the technical field of valve, including valve body, valve rod and pilot assembly, be provided with valve cavity and be connected in the valve cavity's air inlet and first air outlet in the valve body, the valve rod sets up in the valve cavity, and pilot assembly is used for driving the valve rod moves, the valve cavity includes valve core chamber, first seal cavity and second seal cavity, and the first valve core seat is provided in the valve core chamber, and the first valve core seat is opened with first valve core hole, the valve rod outer fixed cover is equipped with valve core cover, first seal ring spare and second seal ring spare, and the valve core cover can with first valve core hole edge sealed abutment to block first valve core hole, and the air inlet and first air outlet set up respectively in the opposite sides of first valve core hole, the opening of first seal cavity, the opening of second seal cavity and the inside diameter of first valve core hole are same, the utility model can effectively reduce the back pressure of the valve core cover in solenoid valve, and the probability of solenoid valve gas leakage is reduced.

Description

Technical Field

[0001] This utility model relates to the technical field of valves, and in particular to a back pressure balanced solenoid valve. Background Technology

[0002] The solenoid valve drives the valve stem to move through the pilot assembly, thereby changing the flow path inside the valve body and realizing the electronic switching of the valve path.

[0003] A traditional solenoid valve includes a valve body, a valve stem, and a pilot assembly. A valve cavity is formed within the valve body, and the valve stem is slidably positioned within the valve cavity under the drive of the pilot assembly. The valve body has an air inlet and at least one working port, which communicate with the valve cavity. A valve core sleeve made of a sealing material such as rubber is fitted around the outer periphery of the valve stem. This valve core sleeve abuts against the inner wall of the valve cavity, thereby sealing and cutting off the air passage between the air inlet and the working port. When the valve stem moves, it opens the air passage between the air inlet and the working port, thus achieving both the cutting off and connection of the air passage between the air inlet and the working port.

[0004] In the aforementioned solenoid valve, the air circuit is cut off by the valve core sleeve on the valve stem abutting against the inner wall of the valve cavity. When air is introduced through the inlet, the air pressure in the section of the valve cavity connected to the inlet is the same as the air pressure introduced through the inlet. That is, the air pressure at the inlet directly acts on the valve core sleeve to form back pressure. When the inlet pressure is too high, the back pressure on the valve core sleeve is too great, which can easily cause the valve core sleeve to shift relative to the valve cavity, resulting in air leakage from the solenoid valve and affecting its operation. Utility Model Content

[0005] The purpose of this invention is to provide a back pressure balanced solenoid valve, which can effectively reduce the back pressure acting on the valve core sleeve inside the solenoid valve and reduce the probability of air leakage in the solenoid valve.

[0006] This utility model provides a back pressure balancing solenoid valve, which includes a valve body, a valve stem, and a pilot assembly. The valve body is provided with a valve cavity and an air inlet and a first air outlet connected to the valve cavity. The valve stem is slidably disposed in the valve cavity along the axis. The pilot assembly is connected to the valve body and is used to drive the valve stem to move. The valve cavity includes a valve core cavity, a first sealing cavity, and a second sealing cavity. A first valve core seat is disposed inside the valve core cavity. The first sealing cavity and the second sealing cavity are respectively disposed on opposite sides of the first valve core seat. The first valve core seat has a first valve core hole. The valve stem passes through the first sealing cavity, the first valve core hole, and the second sealing cavity in sequence. The valve stem is externally fixedly fitted with a valve core sleeve, a first sealing ring, and a second sealing ring. The valve core sleeve can seal against the edge of the first valve core hole to block the first valve core hole. The air inlet and the first air outlet are respectively located on opposite sides of the first valve core hole. The first sealing ring can seal against the opening of the first sealing cavity facing the first valve core seat, and the second sealing ring can seal against the opening of the second sealing cavity facing the first valve core seat. The openings of the first sealing cavity, the second sealing cavity, and the first valve core hole have the same inner diameter.

[0007] Furthermore, both the first sealing cavity and the second sealing cavity are cylindrical cavities of equal diameter, and the inner diameter of the first sealing cavity and the second sealing cavity is the same as the inner diameter of the first valve core hole.

[0008] Furthermore, the outer periphery of both ends of the valve stem is provided with a first sealing groove and a second sealing groove along the circumferential direction, respectively, with the first sealing ring fitting inside the first sealing groove and the second sealing ring fitting inside the second sealing groove.

[0009] Furthermore, the valve body is also provided with a second air outlet communicating with the valve cavity, and a second valve core seat is also provided in the valve core cavity. The second valve core seat is located on the side of the first valve core seat facing the first sealing cavity. The air inlet communicates between the first valve core seat and the second valve core seat, and the second air outlet and the air inlet are located on opposite sides of the second valve core seat. The second valve core seat has a second valve core hole, the inner diameter of which is the same as the inner diameter of the first valve core hole. The valve core sleeve can abut against the edge of the second valve core hole to seal the second valve core hole.

[0010] Furthermore, a first spacer is provided at the opening of the first sealing cavity facing the first valve core seat, and the inner diameter of the first spacer is the same as the inner diameter of the first valve core hole; when the valve core sleeve seals against the edge of the first valve core hole, the first sealing ring seals against the inner ring of the first spacer.

[0011] Furthermore, a second spacer is provided at the opening of the second sealing cavity facing the first valve core seat, and the inner diameter of the second spacer is the same as the inner diameter of the second valve core hole; when the valve core sleeve seals against the edge of the second valve core hole, the second sealing ring seals against the inner ring of the second spacer.

[0012] Furthermore, the valve core sleeve is disposed between the first valve core hole and the second valve core hole, and the outer diameter of the valve core sleeve is larger than the inner diameter of the first valve core hole and the second valve core hole.

[0013] Furthermore, the valve core sleeve has a first guide surface on the side facing the first valve core hole, and the first guide surface is radially outward in a direction away from the first valve core hole; the valve core sleeve has a second guide surface on the side facing the second valve core hole, and the second guide surface is radially outward in a direction away from the second valve core hole.

[0014] Furthermore, the first sealing ring, the second sealing ring, and the valve core sleeve are integrally formed.

[0015] Furthermore, a ring-shaped mounting groove is provided around the valve stem, and the valve core sleeve, the first sealing ring, and the second sealing ring are embedded in the mounting groove.

[0016] In summary, this utility model has the following beneficial effects: 1. In the solenoid valve of this utility model, the valve stem is driven to move within the valve cavity by a pilot assembly; the valve cavity connects the inlet and the first outlet; specifically, the valve cavity includes a valve core cavity, a first sealing cavity, and a second sealing cavity, with a first valve core seat disposed within the valve core cavity, and the inlet and the first outlet located on opposite sides of the first valve core seat; a valve core sleeve is fitted over the valve stem; when the valve stem moves to the point where the valve core sleeve seals against the first valve core hole, the gas entering through the inlet cannot pass through the first valve core hole to enter the first outlet, thus cutting off the gas path from the inlet to the first outlet; when the valve stem moves to the point where the first valve core hole is opened, the gas path from the inlet to the first outlet is connected, thereby enabling the solenoid valve to control the gas path between the first outlet and the inlet. The valve stem is opened and closed; when the valve core sleeve seals against the first valve core hole, the first sealing ring can seal against the opening of the first sealing cavity facing the first valve core seat. Thus, the high-pressure gas entering the valve core cavity through the air inlet acts on the valve core sleeve and the first sealing ring simultaneously. The high-pressure gas exerts a force on the valve core sleeve in a direction away from the first sealing ring, and exerts a force on the first sealing ring in a direction away from the valve core sleeve. Since the inner diameter of the first valve core hole is the same as the inner diameter of the opening of the first sealing cavity facing the first valve core seat, the two forces exerted by the high-pressure gas on the valve stem are balanced. Therefore, even if the back pressure on the air inlet side is large, the valve stem is not easy to displace under the action of air pressure, which would cause the solenoid valve to leak.

[0017] 2. In one embodiment, the first sealing cavity and the second sealing cavity are cylindrical cavities of equal diameter (i.e., the opening diameter of the first sealing cavity and the second sealing cavity are the same as the inner diameter of the cavity). The first sealing ring and the second sealing ring are kept in correspondence with the first sealing cavity and the second sealing cavity to seal. Thus, when the valve stem moves to the valve core sleeve sealingly abuts against the first valve core hole, the high-pressure gas at the inlet acts on the valve core sleeve and the first sealing ring, so that the valve stem is subjected to force balance. When the valve stem moves to the valve core sleeve leaving the first valve core hole, the high-pressure gas at the inlet acts on the first sealing ring and the second sealing ring, maintaining the force balance of the valve stem. This ensures that the force of the high-pressure gas acting on the valve stem is balanced when the first valve core hole is opened and closed, and the valve stem is not easily pressured and moved under the action of high-pressure gas, thus affecting the normal operation of the solenoid valve.

[0018] 3. In one embodiment, the valve body is provided with a second air outlet, and the air path of the air inlet, the first air outlet, and the second air outlet is switched by moving the valve stem. Specifically, when the valve stem moves, the valve core sleeve moves between the first valve core seat and the second valve core seat. When the valve core sleeve seals against the first valve core hole, the air path between the air inlet and the first air outlet is cut off, and the air path between the air inlet and the second air outlet is connected. At this time, high-pressure gas acts on the first sealing ring and the valve core sleeve, so that the valve stem is pressure balanced. When the valve core sleeve seals against the second valve core hole, the air path between the air inlet and the second air outlet is cut off, and the air path between the air inlet and the first air outlet is connected. At this time, high-pressure gas acts on the second sealing ring and the valve core sleeve, so that the valve stem is pressure balanced. Thus, while satisfying the switching of the air path between the two air outlets and the air inlet, the pressure balance of the valve stem is ensured, and the influence of back pressure on the valve stem is reduced. Attached Figure Description

[0019] Figure 1 This is a vertical cross-sectional structural diagram of the solenoid valve of Embodiment 1 of this utility model.

[0020] Figure 2 This is a schematic diagram of the vertical cross-sectional structure of the valve body of Embodiment 1 of this utility model.

[0021] Figure 3 This is a schematic diagram of the vertical cross-sectional structure of the valve stem in Embodiment 1 of this utility model.

[0022] Figure 4 This is a vertical cross-sectional structural diagram of the solenoid valve of Embodiment 2 of this utility model.

[0023] Figure 5 This is a schematic diagram of the vertical cross-sectional structure of the valve body in Embodiment 2 of this utility model.

[0024] Figure 6 This is a schematic diagram of the vertical cross-sectional structure of the valve stem in Embodiment 2 of this utility model.

[0025] In the picture: 1000, Solenoid valve; 100, Valve body; 110, Valve chamber; 111, Valve core chamber; 112, First sealing chamber; 113, Second sealing chamber; 120, Air inlet; 130, First air outlet; 140, First valve core seat; 141, First valve core hole; 150, Second air outlet; 160, Second valve core seat; 161, Second valve core hole; 170, First spacer; 180, Second spacer; 190, Exhaust valve. Air inlet; 200, valve stem; 210, valve core sleeve; 211, first guide surface; 212, second guide surface; 220, first sealing ring; 230, second sealing ring; 240, first sealing groove; 250, second sealing groove; 260, mounting groove; 300, pilot assembly; 310, housing; 320, coil; 330, stationary iron core; 340, moving iron core; 350, frame; 400, return spring. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings.

[0027] Example 1 This embodiment discloses a back pressure balancing solenoid valve 1000, referring to... Figure 1 The solenoid valve 1000 includes a valve body 100, a valve stem 200, and a pilot assembly 300. The valve body 100 has a valve cavity 110 and an air inlet 120 and a first air outlet 130 communicating with the valve cavity 110. The valve stem 200 is slidably disposed in the valve cavity 110 along the axial direction. The pilot assembly 300 is connected to the valve body 100 and is used to drive the valve stem 200 to move.

[0028] Reference Figure 1 The pilot assembly 300 includes a housing 310, a coil 320, a stationary iron core 330, and a moving iron core 340. The housing 310 is fixedly connected to the valve body 100, and its inner cavity communicates with the valve cavity 110. A frame 350 is disposed inside the housing 310, and the coil 320 is wound around the outer periphery of the frame 350. The stationary iron core 330 is fixedly disposed within the frame 350. The moving iron core 340 is axially movable within the frame 350, and the moving iron core 340 abuts against the end of the valve stem 200.

[0029] A return spring 400 is provided at the end of the valve stem 200 away from the moving iron core 340, and the end of the return spring 400 away from the valve stem 200 abuts against the bottom wall of the valve cavity 110. When the coil 320 is energized, the moving iron core 340 moves towards the valve body 100 under the action of magnetic force, pushing the valve stem 200 to move and connect the flow path between the air inlet 120 and the first air outlet 130. At this time, the valve stem 200 compresses the return spring 400. When the coil 320 is de-energized, the moving iron core 340 loses its magnetic force, and the valve stem 200 moves under the elastic force of the return spring 400 to cut off the flow path between the air inlet 120 and the first air outlet 130. This realizes the opening and closing of the solenoid valve 1000.

[0030] Reference Figure 1 and Figure 2 The valve cavity 110 includes a valve core cavity 111, a first sealing cavity 112, and a second sealing cavity 113, which are coaxially arranged. The valve core cavity 111 is located in the middle of the valve body 100, the first sealing cavity 112 is located on the side of the valve core cavity 111 facing the pilot assembly 300, and the second sealing cavity 113 is located on the side of the valve core cavity 111 away from the pilot assembly 300.

[0031] A first valve core seat 140 is provided inside the valve core cavity 111, and the first valve core seat 140 has a first valve core hole 141. The valve stem 200 passes through the first sealing cavity 112, the first valve core hole 141 and the second sealing cavity 113 in sequence.

[0032] Reference Figures 1 to 3 The valve stem 200 is externally fixedly fitted with a valve core sleeve 210, a first sealing ring 220, and a second sealing ring 230. The valve core sleeve 210 is located on the side of the first valve core seat 140 away from the pilot assembly 300, and the valve core sleeve 210 can seal against the edge of the first valve core hole 141 to block the first valve core hole 141. The air inlet 120 and the first air outlet 130 are respectively located on opposite sides of the first valve core hole 141. When the valve stem 200 moves to the point where the valve core sleeve 210 seals against the first valve core hole 141, the gas entering through the inlet 120 cannot pass through the first valve core hole 141 to enter the first outlet 130. At this time, the air passage from the inlet 120 to the first outlet 130 is cut off. When the valve stem 200 moves to the point where the first valve core hole 141 is opened, the air passage from the inlet 120 to the first outlet 130 is connected, thereby realizing the opening and closing of the air passage between the first outlet 130 and the inlet 120 by the solenoid valve 1000.

[0033] The valve stem 200 has two ends located in the first sealing cavity 112 and the second sealing cavity 113, respectively. The first sealing ring 220 seals against the opening of the first sealing cavity 112 facing the first valve core seat 140, and the second sealing ring 230 seals against the opening of the second sealing cavity 113 facing the first valve core seat 140. Thus, the first sealing ring 220 and the second sealing ring 230 block the upper and lower ends of the valve cavity 110, preventing air leakage, while allowing the air pressure from the air inlet 120 to act on the end of the valve stem 200.

[0034] In this embodiment, the openings of the first sealing cavity 112, the second sealing cavity 113, and the inner diameter of the first valve core hole 141 are the same. Therefore, when the valve core sleeve 210 seals against the first valve core hole 141, the first sealing ring 220 seals against the opening of the first sealing cavity 112 facing the first valve core seat 140. Consequently, the high-pressure gas entering the valve core cavity 111 through the air inlet 120 simultaneously acts on both the valve core sleeve 210 and the first sealing ring 220. The high-pressure gas exerts a force on the valve core sleeve 210 in a direction away from the first sealing ring 220, and a force on the first sealing ring 220 in a direction away from the valve core sleeve 210. The two forces acting on the valve stem 200 are balanced, thus even if the back pressure on the air inlet 120 side is large, the valve stem 200 is less likely to displace under pressure, causing leakage in the solenoid valve 1000.

[0035] Specifically, both the first sealing cavity 112 and the second sealing cavity 113 are cylindrical cavities of equal diameter. The inner diameters of both the first sealing cavity 112 and the second sealing cavity 113 are the same as the inner diameter of the first valve core hole 141 (i.e., the opening diameters of the first sealing cavity 112 and the second sealing cavity 113 are the same as the inner cavity diameters, and both are the same as the diameter of the first valve core hole 141). The first sealing ring 220 and the second sealing ring 230 maintain corresponding sealing contact with the first sealing cavity 112 and the second sealing cavity 113. Thus, when the valve stem 200 moves to the point where the valve core sleeve 210 seals against the first valve core hole 141, the high-pressure gas from the air inlet 120 acts on the valve core sleeve 210 and the first sealing ring 220, balancing the forces on the valve stem 200. When the valve stem 200 moves to the point where the valve core sleeve 210 leaves the first valve core hole 141, the high-pressure gas from the air inlet 120 acts on the first sealing ring 220 and the second sealing ring 230, maintaining the force balance on the valve stem 200. This ensures that the force exerted by the high-pressure gas on the valve stem 200 is balanced when the first valve core hole 141 is opened and closed, and the valve stem 200 is less likely to be moved under pressure by the high-pressure gas, thus affecting the normal operation of the solenoid valve 1000.

[0036] In this embodiment, the outer periphery of both ends of the valve stem 200 is provided with a first sealing groove 240 and a second sealing groove 250 along the circumferential direction, respectively. The first sealing ring 220 and the second sealing ring 230 are both annular rubber sealing rings. The first sealing ring 220 is fitted into the first sealing groove 240, and the second sealing ring 230 is fitted into the second sealing groove 250, thereby facilitating the installation of the first sealing ring 220 and the second sealing ring 230.

[0037] Example 2 This embodiment discloses a back pressure balancing solenoid valve 1000, referring to... Figure 4 The solenoid valve 1000 includes a valve body 100, a valve stem 200, and a pilot assembly 300. The valve body 100 has a valve cavity 110 and an air inlet 120, a first air outlet 130, and a second air outlet 150 connected to the valve cavity 110. The valve stem 200 is slidably disposed in the valve cavity 110 along the axial direction. The pilot assembly 300 is connected to the valve body 100 and is used to drive the valve stem 200 to move.

[0038] Reference Figure 1 The pilot assembly 300 includes a housing 310, a coil 320, a stationary iron core 330, and a moving iron core 340. The housing 310 is fixedly connected to the valve body 100, and the inner cavity of the housing 310 corresponds to the valve cavity 110. A frame 350 is disposed inside the housing 310, and the coil 320 is wound around the outer periphery of the frame 350. The stationary iron core 330 is fixedly disposed inside the frame 350. The moving iron core 340 is axially movable within the frame 350, and the moving iron core 340 abuts against the end of the valve stem 200.

[0039] A return spring 400 is installed at the end of the valve stem 200 away from the moving iron core 340, and the end of the return spring 400 away from the valve stem 200 abuts against the bottom wall of the valve cavity 110. When the coil 320 is energized, the moving iron core 340 moves towards the valve body 100 under the action of magnetic force, at which time the valve stem 200 compresses the return spring 400. When the coil 320 is de-energized, the moving iron core 340 loses its magnetic force, and the valve stem 200 moves under the elastic force of the return spring 400.

[0040] Reference Figure 4 and Figure 5 The valve cavity 110 includes a valve core cavity 111, a first sealing cavity 112, and a second sealing cavity 113, which are coaxially arranged. The valve core cavity 111 is located in the middle of the valve body 100, the first sealing cavity 112 is located on the side of the valve core cavity 111 facing the pilot assembly 300, and the second sealing cavity 113 is located on the side of the valve core cavity 111 away from the pilot assembly 300.

[0041] A first valve core seat 140 and a second valve core seat 160 are disposed within the valve core cavity 111. The second valve core seat 160 is located on the side of the first valve core seat 140 facing the first sealing cavity 112, and an air inlet 120 connects the first valve core seat 140 and the second valve core seat 160. The first valve core seat 140 has a first valve core hole 141, and the second valve core seat 160 has a second valve core hole 161. The inner diameter of the second valve core hole 161 is the same as the inner diameter of the first valve core hole 141.

[0042] Reference Figures 4 to 6 The valve stem 200 passes sequentially through the first sealing cavity 112, the first valve core hole 141, the second valve core hole 161, and the second sealing cavity 113. The valve stem 200 is externally fixedly fitted with a valve core sleeve 210, a first sealing ring 220, and a second sealing ring 230.

[0043] A valve core sleeve 210 is disposed between a first valve core seat 140 and a second valve core seat 160, and the valve core sleeve 210 is movable between the first valve core seat 140 and the second valve core seat 160. The outer diameter of the valve core sleeve 210 is larger than the inner diameter of the first valve core hole 141 and the second valve core hole 161, so that the valve core sleeve 210 can seal against the edge of the first valve core hole 141 to block the first valve core hole 141, and the valve core sleeve 210 can also seal against the edge of the second valve core hole 161.

[0044] In this embodiment, the air inlet 120 and the first air outlet 130 are respectively disposed on opposite sides of the first valve core hole 141, and the air inlet 120 and the second air outlet 150 are disposed on opposite sides of the second valve core seat 160.

[0045] When the valve stem 200 moves away from the pilot assembly 300 until the valve core sleeve 210 seals against the first valve core hole 141, the valve core sleeve 210 leaves the second valve core hole 161. The gas entering through the inlet 120 cannot pass through the first valve core hole 141 to enter the first outlet 130. At this time, the air path from the inlet 120 to the first outlet 130 is cut off, and the air path from the inlet 120 to the second outlet 150 is connected. When the valve stem 200 moves toward the pilot assembly 300 to open the first valve core hole 141, the valve core sleeve 210 leaves the first valve core hole 141 and seals against the second valve core hole 161. At this time, the air passage from the inlet 120 to the first outlet 130 is connected, and the air passage from the inlet 120 to the second outlet 150 is cut off, thereby realizing the opening and closing of the air passage between the first outlet 130, the second outlet 150 and the inlet 120 of the solenoid valve 1000.

[0046] The two ends of the valve stem 200 are located in the first sealing cavity 112 and the second sealing cavity 113 respectively, such that the first sealing ring 220 is located in the first sealing cavity 112 and the second sealing ring 230 is located in the second sealing cavity 113.

[0047] A first spacer 170 is provided at the opening of the first sealing cavity 112 facing the first valve core seat 140. The inner diameter of the first spacer 170 is the same as the inner diameter of the first valve core hole 141. A first sealing ring 220 is provided on the side of the first spacer 170 near the pilot assembly 300, and the outer diameter of the first sealing ring 220 is larger than the inner diameter of the first spacer 170.

[0048] A second spacer 180 is provided at the opening of the second sealing cavity 113 facing the first valve core seat 140. The inner diameter of the second spacer 180 is the same as the inner diameter of the second valve core hole 161. A second sealing ring 230 is provided on the side of the second spacer 180 away from the pilot assembly 300, and the outer diameter of the second sealing ring 230 is larger than the inner diameter of the second spacer 180.

[0049] When the pilot assembly 300 drives the valve stem 200 to move away from the pilot assembly 300, the valve core sleeve 210 seals against the edge of the first valve core hole 141, and the first sealing ring 220 seals against the inner ring of the first spacer 170. When the return spring 400 drives the valve stem 200 to move closer to the pilot assembly 300, the valve core sleeve 210 seals against the edge of the second valve core hole 161, and the second sealing ring 230 seals against the inner ring of the second spacer 180.

[0050] Therefore, when the valve core sleeve 210 seals against the first valve core hole 141, the air path between the inlet 120 and the first outlet 130 is cut off, while the air path between the inlet 120 and the second outlet 150 is connected. At this time, high-pressure gas acts on the first sealing ring 220 and the valve core sleeve 210, causing the valve stem 200 to be pressure balanced. When the valve core sleeve 210 seals against the second valve core hole 161, the air path between the inlet 120 and the second outlet 150 is cut off, while the air path between the inlet 120 and the first outlet 130 is connected. At this time, high-pressure gas acts on the second sealing ring 230 and the valve core sleeve 210, causing the valve stem 200 to be pressure balanced. Thus, while satisfying the air path switching between the two outlets and the inlet 120, the pressure balance of the valve stem 200 is ensured, reducing the impact of back pressure on the valve stem 200.

[0051] In this embodiment, the first sealing ring 220, the second sealing ring 230, and the valve core sleeve 210 are integrally formed, thus requiring only one installation to install the first sealing ring 220, the second sealing ring 230, and the valve core sleeve 210 on the valve stem 200. In this embodiment, the first sealing ring 220, the second sealing ring 230, and the valve core sleeve 210 can be made of flexible sealing materials such as rubber.

[0052] The valve stem 200 has an annular mounting groove 260 around its periphery. The valve core sleeve 210, the first sealing ring 220, and the second sealing ring 230 are embedded in the mounting groove 260 to facilitate the positioning and installation of the first sealing ring 220, the second sealing ring 230, and the valve core sleeve 210. At the same time, the mounting groove 260 limits the axial movement of the first sealing ring 220, the second sealing ring 230, and the valve core sleeve 210 to prevent them from shifting axially along the valve stem 200.

[0053] The valve core sleeve 210 has a first guide surface 211 on the side facing the first valve core hole 141, and the first guide surface 211 is radially outward in a direction away from the first valve core hole 141. The valve core sleeve 210 has a second guide surface 212 on the side facing the second valve core hole 161, and the second guide surface 212 is radially outward in a direction away from the second valve core hole 161, that is, the cross section of the valve core sleeve 210 through the valve stem 200 is trapezoidal. The arrangement of the first guide surface 211 and the second guide surface 212 makes the valve core sleeve 210 more tightly sealed and abutting against the first valve core hole 141 and the second valve core hole 161, resulting in better airtightness.

[0054] Reference Figure 4 and Figure 5 The valve body 100 is also provided with an exhaust port 190. The exhaust port 190 is connected to the first sealing cavity 112 and the second sealing cavity 113. When the valve stem 200 moves toward the pilot assembly 300, so that the valve core sleeve 210 seals against the second valve core hole 161, the first air outlet 130 is connected to the air inlet 120, the first sealing ring 220 moves away from the first spacer 170, the second air outlet 150 is connected to the first sealing cavity 112 and thus connected to the exhaust port 190, and the second sealing ring 230 seals against the second spacer 180 to cut off the first air outlet 130 and the second sealing cavity 113. When the valve stem 200 moves away from the pilot assembly 300, causing the valve core sleeve 210 to seal against the first valve core hole 141, the second air outlet 150 connects to the air inlet 120, the second sealing ring 230 moves away from the second spacer 180, the first air outlet 130 connects to the second sealing cavity 113 and thus to the exhaust port 190, and the first sealing ring 220 seals against the first spacer 170 to cut off the second air outlet 150 and the first sealing cavity 112. Thus, the first air outlet 130 and the second air outlet 150 can serve as two working ports; when one working port receives air, the other working port can exhaust air.

[0055] The above description is only a preferred embodiment of the present utility model. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the claims of the present utility model patent application are included in the scope of the present utility model patent application.

Claims

1. A back pressure balanced solenoid valve, characterized in that, The solenoid valve (1000) includes a valve body (100), a valve stem (200), and a pilot assembly (300). The valve body (100) is provided with a valve cavity (110) and an air inlet (120) and a first air outlet (130) communicating with the valve cavity (110). The valve stem (200) is slidably disposed in the valve cavity (110) along the axial direction. The pilot assembly (300) is connected to the valve body (100) and is used to drive the valve stem (200) to move. The valve chamber (110) includes a valve core chamber (111), a first sealing chamber (112), and a second sealing chamber (113). A first valve core seat (140) is disposed in the valve core chamber (111). The first sealing chamber (112) and the second sealing chamber (113) are respectively disposed on opposite sides of the first valve core seat (140). The first valve core seat (140) has a first valve core hole (141). The valve stem (200) passes through the first sealing chamber (112), the first valve core hole (141), and the second sealing chamber (113) in sequence. The valve stem (200) is externally fixedly fitted with a valve core sleeve (210), a first sealing ring (220), and a second sealing ring (230). The valve core sleeve (210) can seal against the edge of the first valve core hole (141) to block the first valve core hole (141). The air inlet (120) and the first air outlet (130) are respectively located on opposite sides of the first valve core hole (141). The first sealing ring (220) can seal against the opening of the first sealing cavity (112) facing the first valve core seat (140), and the second sealing ring (230) can seal against the opening of the second sealing cavity (113) facing the first valve core seat (140). The openings of the first sealing cavity (112), the second sealing cavity (113), and the first valve core hole (141) have the same inner diameter.

2. The back pressure balanced solenoid valve as described in claim 1, characterized in that, The first sealing cavity (112) and the second sealing cavity (113) are both cylindrical cavities of equal diameter, and the inner diameter of the first sealing cavity (112) and the second sealing cavity (113) is the same as the inner diameter of the first valve core hole (141).

3. The back pressure balanced solenoid valve as described in claim 2, characterized in that, The valve stem (200) has a first sealing groove (240) and a second sealing groove (250) respectively arranged circumferentially on the outer periphery of both ends. The first sealing ring (220) is sleeved in the first sealing groove (240) and the second sealing ring (230) is sleeved in the second sealing groove (250).

4. The back pressure balanced solenoid valve as described in claim 1, characterized in that, The valve body (100) is also provided with a second air outlet (150) communicating with the valve cavity (110). The valve core cavity (111) is also provided with a second valve core seat (160). The second valve core seat (160) is located on the side of the first valve core seat (140) facing the first sealing cavity (112). The air inlet (120) is connected between the first valve core seat (140) and the second valve core seat (160). The second air outlet (150) and the air inlet (120) are located on opposite sides of the second valve core seat (160). The second valve core seat (160) has a second valve core hole (161). The inner diameter of the second valve core hole (161) is the same as the inner diameter of the first valve core hole (141). The valve core sleeve (210) can abut against the edge of the second valve core hole (161) to block the second valve core hole (161).

5. A back pressure balanced solenoid valve as described in claim 4, characterized in that, A first spacer (170) is provided at the opening of the first sealing cavity (112) facing the first valve core seat (140). The inner diameter of the first spacer (170) is the same as the inner diameter of the first valve core hole (141). When the valve core sleeve (210) seals against the edge of the first valve core hole (141), the first sealing ring (220) seals against the inner ring of the first spacer (170).

6. A back pressure balanced solenoid valve as described in claim 4, characterized in that, A second spacer (180) is provided at the opening of the second sealing cavity (113) facing the first valve core seat (140). The inner diameter of the second spacer (180) is the same as the inner diameter of the second valve core hole (161). When the valve core sleeve (210) seals against the edge of the second valve core hole (161), the second sealing ring (230) seals against the inner ring of the second spacer (180).

7. A back pressure balanced solenoid valve as described in claim 4, characterized in that, The valve core sleeve (210) is disposed between the first valve core hole (141) and the second valve core hole (161), and the outer diameter of the valve core sleeve (210) is greater than the inner diameter of the first valve core hole (141) and the second valve core hole (161).

8. A back pressure balanced solenoid valve as described in claim 4, characterized in that, The valve core sleeve (210) has a first guide surface (211) on the side facing the first valve core hole (141), and the first guide surface (211) is radially outward in a direction away from the first valve core hole (141); the valve core sleeve (210) has a second guide surface (212) on the side facing the second valve core hole (161), and the second guide surface (212) is radially outward in a direction away from the second valve core hole (161).

9. A back pressure balanced solenoid valve as described in claim 4, characterized in that, The first sealing ring (220), the second sealing ring (230), and the valve core sleeve (210) are integrally formed.

10. A back pressure balanced solenoid valve as described in claim 9, characterized in that, The valve stem (200) has a ring-shaped mounting groove (260) around its periphery, and the valve core sleeve (210), the first sealing ring (220) and the second sealing ring (230) are embedded in the mounting groove (260).

Images