Vacuum protection valve and vacuumizing equipment

Abstract

The utility model discloses a vacuum protection valve and vacuumizing equipment. The vacuum protection valve comprises a valve body assembly, a valve cover assembly and an air inflation assembly. The valve body assembly is provided with an air cavity; the valve cover assembly is movably arranged in the air cavity; the inflation assembly is movably arranged in the air cavity in a penetrating mode through the opening of the second end, the inflation assembly is connected with the edge of the opening of the second end in a sealed mode, the inflation assembly is movably connected with the valve deck assembly, the inflation assembly is provided with a first inflation opening, and in the first direction, the inflation assembly has a first moving stroke and a second moving stroke which are conducted in sequence. The vacuum protection valve can conduct vacuum protection on the oil diffusion pump and conduct vacuum breaking on the exhaust pipeline between the oil diffusion pump and the maintaining pump at the same time.

Description

Technical Field

[0001] The present application relates to the technical field of vacuum equipment, and in particular to a vacuum protection valve and a vacuum equipment. Background Art

[0002] In vacuum equipment, the oil diffusion pump is used to utilize oil vapor jet to evacuate air to achieve the purpose of evacuating the vacuum chamber. The temperature of the oil in the oil diffusion pump is very high when it is working. Before the oil temperature drops to room temperature, it is usually necessary to maintain the pump (such as a rotary vane pump) to continue working to avoid oil oxidation and affect the pumping performance of the oil diffusion pump. However, in actual working conditions, in order to shorten the shutdown time of the equipment, the maintenance pump is usually shut down before the oil temperature drops to room temperature. In this way, the oil diffusion pump needs to be vacuum protected. At the same time, in order to prevent the oil in the pump from flowing back to the exhaust pipe between the oil diffusion pump and the maintenance pump under the action of atmospheric pressure after the maintenance pump is stopped, causing pollution to the exhaust pipe, it is also necessary to inflate the exhaust pipe between the oil diffusion pump and the maintenance pump after the oil diffusion pump is vacuum protected to break the vacuum in the exhaust pipe between the oil diffusion pump and the maintenance pump. Utility Model Content

[0003] In view of this, the purpose of the present application is to overcome the deficiencies in the prior art and to provide a vacuum protection valve that can simultaneously provide vacuum protection for the oil diffusion pump and break the vacuum in the exhaust pipe between the oil diffusion pump and the maintenance pump.

[0004] The present application also provides a vacuum pumping device.

[0005] To achieve the above objectives, the technical solutions adopted in this application are as follows:

[0006] According to the vacuum protection valve of the first aspect of the present application, the invention comprises: a valve body assembly, wherein the valve body assembly is provided with an air cavity, wherein the air cavity has a first end, a second end and a third end which are arranged at intervals, and the first end is arranged in front of the second end along the first direction, and the first end, the second end and the third end are all provided with openings; a valve cover assembly, wherein the valve cover assembly is movably arranged in the air cavity; an inflatable assembly, wherein the inflatable assembly is movably arranged in the air cavity through the opening of the second end, and the inflatable assembly is sealed and connected to the opening edge of the second end, the inflatable assembly is movably connected to the valve cover assembly, the inflatable assembly is provided with a first inflating port, and in the first direction, the inflatable assembly has a first moving stroke and a second moving stroke which are performed successively; wherein, in the first moving stroke, the valve cover assembly moves synchronously with the inflatable assembly and moves to seal against the cavity wall of the first end, and the first inflating port is located outside the air cavity, and in the second moving stroke, the valve cover assembly seals against the cavity wall of the first end, and the first inflating port enters the air cavity through the second end.

[0007] The vacuum protection valve of the present application has the following advantages:

[0008] In the above-mentioned vacuum protection valve, the above-mentioned vacuum protection valve is arranged on the air extraction pipeline between the oil diffusion pump and the maintenance pump, and the opening of the first end of the air cavity is used to communicate with the air extraction pipeline close to the oil diffusion pump, and the opening of the third end of the air cavity is used to communicate with the air extraction pipeline close to the maintenance pump. Therefore, when the above-mentioned vacuum protection valve is not closed, the oil diffusion pump and the maintenance pump can be connected through the air cavity, so that the maintenance pump and the oil diffusion pump can be pumped through the air extraction pipeline to achieve vacuum. When it is necessary to close the air extraction pipeline between the oil diffusion pump and the maintenance pump, the inflation assembly and the valve cover assembly can be synchronously moved relative to the valve body assembly, so that the valve cover assembly can be sealed against the cavity wall of the first end of the air cavity, so as to achieve the closing of the above-mentioned vacuum protection valve, thereby disconnecting the air extraction pipeline between the oil diffusion pump and the maintenance pump, thereby achieving vacuum protection for the oil diffusion pump. In this process, in the first movement stroke of the inflation assembly, since the valve cover assembly moves synchronously with the inflation assembly and moves to be sealed against the cavity wall of the first end, and the third movement stroke of the inflation assembly, the valve cover assembly moves synchronously with the inflation assembly and moves to be sealed against the cavity wall of the first end, and the third movement stroke of the inflation ... An inflation port is located outside the air cavity. Therefore, it can be ensured that during the closing process of the above-mentioned vacuum protection valve, air cannot be inflated into the air cavity through the first inflation port. In this way, vacuum protection of the oil diffusion pump can be achieved. Furthermore, in the second moving stroke of the inflation component, the first inflation port can enter the air cavity through the second end, so that gas is filled into the air cavity through the first inflation port, which can break the vacuum of the maintenance pump, so as to prevent the working oil of the maintenance pump from flowing back into the exhaust pipe under the action of atmospheric pressure, thereby avoiding pollution of the exhaust pipe.

[0009] According to the vacuum protection valve of the first aspect of the present application, the valve cover assembly includes a valve cover, the valve body assembly includes a valve body, the valve body is provided with the air cavity, and the valve cover is movably disposed in the air cavity.

[0010] According to the vacuum protection valve of the first aspect of the present application, in the second direction, a sealing portion is defined between the opening of the first end and the cavity wall of the air cavity, the valve cover has a sealing surface along the first direction, and the valve cover moves along the first direction so that the edge of the sealing surface abuts against the sealing portion;

[0011] The second direction is perpendicular to the first direction, the opening of the first end has a diameter of L1, and the cavity diameter of the air cavity is L2, satisfying: L1<L2.

[0012] According to the vacuum protection valve of the embodiment of the first aspect of the present application, in the second direction, the minimum width of the sealing surface is L3, which satisfies: L3≥L1, L3<L2.

[0013] According to the vacuum protection valve of the embodiment of the first aspect of the present application, the valve body assembly further comprises a cover plate covered on the second end, the cover plate is provided with a sealing through hole extending along the first direction, one end of the sealing through hole is connected to the air cavity through the opening of the second end, the inflatable assembly comprises an inflatable member, the inflatable member is movably provided in the sealing through hole and is sealedly connected to the hole wall of the sealing through hole, the inflatable member is movably connected to the valve cover, and moves relative to the valve cover along the first direction;

[0014] Among them, the first inflation port is opened on the inflatable member, and in the first direction, the inflatable member has the first movement stroke and the second movement stroke which are performed successively. In the first movement stroke, the first inflation port is located behind one end of the sealing through hole near the air cavity.

[0015] According to the vacuum protection valve of the first aspect of the embodiment of the present application, in the first direction, the distance of the first moving stroke is S1, the distance of the second moving stroke is S2, and before the inflatable part moves, the distance between the first inflation port and the end of the sealing through hole close to the air cavity is S3, satisfying: S1+S2≥S3, and S1<S3.

[0016] According to the vacuum protection valve of the first aspect of the present application, in the first direction, the valve cover assembly has a third movement stroke. In the third movement stroke, the valve cover assembly moves to seal against the cavity wall of the first end. The distance of the third movement stroke is S4, satisfying: S1+S2>S4.

[0017] According to the vacuum protection valve of the embodiment of the first aspect of the present application, the inflation component is further provided with a second inflation port and an inflation channel, the second inflation port and the inflation channel are both provided on the inflation component, the inflation channel is extended along the first direction, the first inflation port is communicated with an end of the inflation channel close to the air cavity, and the second inflation port is communicated with an end of the inflation channel away from the air cavity;

[0018] Wherein, before the inflatable member moves, the distance between the second inflatable port and the end of the sealing through hole away from the air cavity is S5, satisfying: S5>S1+S2.

[0019] According to the vacuum protection valve of the first aspect of the present application, the valve cover assembly also includes an elastic support member, the valve cover is provided with a receiving groove with an opening toward the second end, the receiving groove is extended along the first direction, the elastic support member is arranged in the receiving groove, one end of the inflatable member along the first direction is penetrated into the receiving groove, and the two ends of the elastic support member along the first direction are respectively connected to the bottom of the receiving groove and the inflatable member.

[0020] The vacuum pumping equipment according to the second embodiment of the present application includes: the vacuum protection valve as described above.

[0021] The vacuum equipment of the present application has the following advantages:

[0022] In the above-mentioned vacuum pumping equipment, since the above-mentioned vacuum protection valve can simultaneously perform vacuum protection on the oil diffusion pump and break the vacuum of the exhaust pipe between the oil diffusion pump and the maintenance pump, the above-mentioned vacuum pumping equipment can achieve better vacuum pumping performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 The cross-sectional structure diagram of the vacuum protection valve of the present application is shown Figure 1 ;

[0025] Figure 2 The cross-sectional structure diagram of the vacuum protection valve of the present application is shown in FIG. Figure 2 ;

[0026] Figure 3 The cross-sectional structure diagram of the vacuum protection valve of the present application is shown in FIG. Figure 3 ;

[0027] Figure 4 A schematic cross-sectional view of the valve body assembly of the present application is shown;

[0028] Figure 5 A schematic cross-sectional view of the valve cover assembly of the present application is shown;

[0029] Figure 6 A schematic cross-sectional structure diagram of the inflation assembly and the cover plate of the present application is shown.

[0030] Description of main component symbols:

[0031] 100-valve body assembly; 110-air cavity; 111-first end; 112-second end; 113-third end; 120-valve body; 121-sealing part; 130-cover plate; 131-sealing through hole; 132-second sealing ring;

[0032] 200-valve cover assembly; 210-valve cover; 211-sealing surface; 212-accommodating groove; 213-first sealing ring; 220-elastic support member;

[0033] 300 - inflation component; 310 - first inflation port; 320 - inflation piece; 330 - second inflation port; 340 - inflation channel; 350 - base; 351 - vent. DETAILED DESCRIPTION

[0034] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0035] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0036] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0037] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0038] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0039] Reference Figure 1 , Figure 2 as well as Figure 3 As shown, the vacuum protection valve involved in the embodiment of the present application includes: a valve body assembly 100, a valve cover assembly 200 and an inflation assembly 300.

[0040] Specifically, the valve body assembly 100 is provided with an air cavity 110, and the air cavity 110 has a first end 111, a second end 112 and a third end 113 which are arranged at intervals, and the first end 111 is arranged in front of the second end 112 along the first direction, and the first end 111, the second end 112 and the third end 113 are all provided with openings; the valve cover assembly 200 is movably arranged in the air cavity 110; the inflatable assembly 300 is movably penetrated in the air cavity 110 through the opening of the second end 112, and the inflatable assembly 300 is sealed and connected to the opening edge of the second end 112, the inflatable assembly 300 is movably connected to the valve cover assembly 200, and the inflatable assembly 300 is provided with a first inflation port 310, and in the first direction, the inflatable assembly 300 has a first movement stroke and a second movement stroke which are performed successively; wherein, in the first movement stroke, that is, by Figure 1 The state changes to Figure 2 During the movement process of the state, the valve cover assembly 200 and the inflation assembly 300 move synchronously and move to the cavity wall seal against the first end 111, and the first inflation port 310 is located outside the air cavity 110. In the second movement stroke, that is, Figure 2 The state changes to Figure 3 During the movement of the state, the valve cover assembly 200 is sealed against the cavity wall of the first end 111 , and the first inflation port 310 enters into the air cavity 110 through the second end 112 .

[0041] It should be noted that the first direction is Figure 1 The direction that x points to.

[0042] In the above-mentioned vacuum protection valve, the above-mentioned vacuum protection valve is arranged on the exhaust pipe between the oil diffusion pump and the maintenance pump, and the opening of the first end 111 of the air cavity 110 is used to communicate with the exhaust pipe close to the oil diffusion pump, and the opening of the third end 113 of the air cavity 110 is used to communicate with the exhaust pipe close to the maintenance pump. Therefore, when the above-mentioned vacuum protection valve is not closed, the oil diffusion pump and the maintenance pump can be connected through the air cavity 110, so that the maintenance pump and the oil diffusion pump can exhaust air through the exhaust pipe to achieve vacuum. When it is necessary to close the air extraction pipeline between the oil diffusion pump and the maintenance pump, the inflation component 300 and the valve cover component 200 can be moved synchronously relative to the valve body component 100, so that the valve cover component 200 can be sealed against the cavity wall of the first end 111 of the air cavity 110, so as to achieve the closure of the above-mentioned vacuum protection valve, thereby disconnecting the air extraction pipeline between the oil diffusion pump and the maintenance pump, thereby achieving vacuum protection for the oil diffusion pump. In this process, in the first movement stroke of the inflation component 300, the valve cover component 200 moves synchronously with the inflation component 300 and moves to be sealed against the cavity wall of the first end 111, and the first inflation port 310 is located in the air cavity 11 0, therefore, it can be ensured that during the closing process of the above-mentioned vacuum protection valve, air cannot be inflated into the air cavity 110 through the first inflation port 310, so as to prevent the inflation gas from entering the oil diffusion pump through the first end 111. In this way, vacuum protection of the oil diffusion pump can be achieved. Furthermore, in the second moving stroke of the inflation component 300, the first inflation port 310 can enter the air cavity 110 through the second end 112, so that gas is filled into the air cavity 110 through the first inflation port 310, and the vacuum of the maintenance pump can be broken, so as to prevent the working oil of the maintenance pump from flowing back into the exhaust pipe under the action of atmospheric pressure, thereby avoiding pollution to the exhaust pipe.

[0043] Reference Figure 4 as well as Figure 5 As shown, the valve cover assembly 200 includes a valve cover 210 , and the valve body assembly 100 includes a valve body 120 . The valve body 120 is provided with an air cavity 110 , and the valve cover 210 is movably disposed in the air cavity 110 .

[0044] It is understandable that the valve cover 210 can move in the air cavity 110 along the first direction so that the valve cover 210 and the cavity wall of the first end 111 are sealed against each other, thereby achieving the closure of the above-mentioned vacuum protection valve.

[0045] Reference Figure 1 As shown, in the second direction, a sealing portion 121 is defined between the opening of the first end 111 and the cavity wall of the air cavity 110, the valve cover 210 has a sealing surface 211, and the valve cover 210 moves along the first direction so that the edge of the sealing surface 211 abuts against the sealing portion 121;

[0046] The second direction is perpendicular to the first direction, the diameter of the opening of the first end 111 is L1, and the diameter of the air cavity 110 is L2, satisfying: L1<L2.

[0047] It should be noted that the second direction is Figure 1 The direction indicated by y is the radial direction of the valve cover 210 .

[0048] Specifically, in the above-mentioned embodiment, a first sealing ring 213 is provided at the edge of the sealing surface 211. When the edge of the sealing surface 211 abuts against the sealing portion 121, the first sealing ring 213 is located between the sealing surface 211 and the sealing portion 121, thereby improving the sealing between the sealing surface 211 and the sealing portion 121.

[0049] It is understandable that when the valve cover 210 moves along the first direction, the edge of the sealing surface 211 can be abutted against the sealing portion 121, so that the opening of the first end 111 is sealed by the sealing surface 211, thereby isolating the air cavity 110 from the air extraction pipeline close to the oil diffusion pump, and realizing the closure of the above-mentioned vacuum protection valve. In this process, if the caliber L1 of the opening of the first end 111 and the cavity diameter L2 of the air cavity 110 satisfy: L1 ≥ L2, then when the vacuum protection valve is closed, the sealing of the first end 111 cannot be guaranteed. If the caliber L1 of the opening of the first end 111 and the cavity diameter L2 of the air cavity 110 satisfy: L1 < L2, then the edge of the sealing surface 211 can be guaranteed to abut against the sealing portion 121, so as to ensure that the opening of the first end 111 can be sealed by the valve cover 210, and the sealing of the first end 111 is improved.

[0050] Continue to refer to Figure 1 As shown, in the second direction, the minimum width of the sealing surface 211 is L3, satisfying: L3≥L1, L3<L2.

[0051] It can be understood that if the minimum width L3 of the sealing surface 211 and the diameter L1 of the opening of the first end 111 satisfy: L3<L1, when the valve cover 210 moves along the first direction, it cannot be guaranteed that the opening of the first end 111 is completely covered by the valve cover 210, so that the sealing performance of the first end 111 is reduced. If the minimum width L3 of the sealing surface 211 and the diameter L1 of the opening of the first end 111 satisfy: L3≥L1, it can be guaranteed that the edges of the opening of the first end 111 are covered by the sealing surface 211, so as to ensure that the opening of the first end 111 is completely covered by the valve cover 210, thereby improving the sealing performance of the first end 111. At the same time, if the minimum width L3 of the sealing surface 211 and the cavity diameter L2 of the air cavity 110 satisfy: L3>L2, the valve cover 210 will not be able to move in the air cavity 110 along the first direction, thereby affecting the response performance of the above-mentioned vacuum protection valve.

[0052] Reference Figure 4 as well as Figure 6 As shown, the valve body assembly 100 includes a cover plate 130, which is covered on the second end 112, and the cover plate 130 is provided with a sealing through hole 131 extending along the first direction, and one end of the sealing through hole 131 is connected through the open air cavity 110 of the second end 112, and the inflatable assembly 300 includes an inflatable member 320, which is movably arranged in the sealing through hole 131 along the first direction and is sealed and connected to the hole wall of the sealing through hole 131, and the inflatable member 320 is movably connected to the valve cover 210, and the inflatable member 320 moves relative to the valve cover 210 along the first direction;

[0053] The first inflation port 310 is provided on the inflation member 320 . In the first movement stroke, in the first direction, the first inflation port 310 is located behind one end of the sealing through hole 131 close to the air cavity 110 .

[0054] Specifically, in the above-mentioned embodiment, a second sealing ring 132 is provided on the hole wall of the sealing through hole 131 to ensure the sealing between the inflatable member 320 and the hole wall of the sealing through hole 131 .

[0055] It can be understood that in the first movement stroke of the inflatable member 320, the inflatable member 320 is penetrated in the sealing through hole 131 along the first direction, so as to realize the movement of the inflatable member 320 relative to the valve body assembly 100, thereby driving the valve cover 210 to move synchronously along the first direction through the inflatable member 320, so that the valve cover 210 can be sealed against the cavity wall of the first end 111. At this time, in the first direction, the first inflation port 310 is located behind one end of the sealing through hole 131 near the air cavity 110. In this way, the first inflation port 310 can be sealed by the hole wall of the sealing through hole 131 to prevent the inflation gas from entering through the first inflation port 310. Into the air cavity 110, so as to prevent the inflation gas from entering the oil diffusion pump through the first end 111, so as to achieve vacuum protection for the oil diffusion pump. In the second movement stroke of the inflation member 320, the inflation member 320 moves along the first direction relative to the valve cover 210, so that the inflation member 320 can continue to move along the first direction relative to the valve body assembly 100, so that the first inflation port 310 can enter the air cavity 110 through the opening of the first end 111, so as to fill the air cavity 110 with gas through the first inflation port 310, thereby preventing the working oil of the pump from flowing back into the exhaust pipe under the action of atmospheric pressure, thereby avoiding pollution to the exhaust pipe.

[0056] Reference Figure 1 as well as Figure 3As shown, in the first direction, the distance of the first moving stroke is S1, the distance of the second moving stroke is S2, and before the inflatable member 320 moves, the distance between the first inflation port 310 and the end of the sealing through hole 131 close to the air cavity 110 is S3, satisfying: S1+S2≥S3, and S1<S3.

[0057] It can be understood that if S1 ≥ S3, the first inflation port 310 will be exposed outside the sealing through hole 131 during the first movement. In this way, the inflation process will be started before the valve cover 210 is closed, and the inflation gas will briefly enter the oil diffusion pump, causing the oil to be oxidized, affecting the pumping performance of the oil diffusion pump. When S1 < S3, the first inflation port 310 can be hidden in the sealing through hole 131 during the first movement, so that the first inflation port 310 can be sealed by the hole wall of the sealing through hole 131 to prevent the inflation gas from passing through. The first inflation port 310 enters the air cavity 110, so as to prevent the inflation gas from entering the oil diffusion pump through the first end 111, thereby realizing vacuum protection of the oil diffusion pump. At the same time, when S1+S2≥S3, after the first moving stroke and the second moving stroke, it can be ensured that the first inflation port 310 enters the air cavity 110 through the opening of the first end 111, so as to fill the air cavity 110 through the first inflation port 310, thereby preventing the working oil of the pump from flowing back into the exhaust pipe under the action of atmospheric pressure, thereby avoiding pollution to the exhaust pipe.

[0058] Continue to refer to Figure 1 as well as Figure 3 As shown, in the first direction, the valve cover assembly 200 has a third movement stroke. In the third movement stroke, the valve cover assembly 200 moves to seal against the cavity wall of the first end 111. The distance of the third movement stroke is S4, satisfying: S1+S2>S4.

[0059] It can be understood that if S1+S2≤S4, the first inflation port 310 will have entered the air cavity 110 before the valve cover 210 and the cavity wall seal of the first end 111 are abutted, and the inflation process will be opened before the valve cover 210 is closed, and the inflation gas will briefly enter the oil diffusion pump, causing the oil to be oxidized, affecting the air pumping performance of the oil diffusion pump. When S1+S2>S4, it can be ensured that the first inflation port 310 enters the air cavity 110 after the valve cover 210 and the cavity wall seal of the first end 111 are abutted, so that it is opened after the inflation process and before the valve cover 210 is closed, thereby avoiding the inflation gas from entering the oil diffusion pump through the first end 111, thereby realizing vacuum protection of the oil diffusion pump.

[0060] Continue to refer to Figure 1 as well as Figure 3As shown, the inflatable component 300 is provided with a second inflatable port 330 and an inflatable channel 340, both of which are provided on the inflatable member 320, and the inflatable channel 340 is extended along the first direction, the first inflatable port 310 is communicated with an end of the inflatable channel 340 close to the air cavity 110, and the second inflatable port 330 is communicated with an end of the inflatable channel 340 away from the air cavity 110;

[0061] Before the inflatable member 320 moves, the distance between the second inflatable port 330 and the end of the sealing through hole 131 away from the air cavity 110 is S5, which satisfies: S5>S1+S2.

[0062] Specifically, in the above embodiment, the inflation component 300 also includes a base 350, and the inflation piece 320 is movably arranged on the base 350 along a first direction. A vent hole 351 is provided on the base 350, one end of the vent hole 351 is connected to the outside, and the other end of the vent hole 351 is connected to the second inflation port 330.

[0063] More specifically, in the above-mentioned embodiment, the inflation component 300 is a cylinder, the inflation member 320 is a piston rod of the cylinder, an inflation channel 340 extending along a first direction is provided inside the piston rod, a first inflation port 310 and a second inflation port 330 are provided on the side wall of the piston rod, the base 350 is a cylinder barrel of the cylinder, a vent hole 351 is provided on the wall of the cylinder barrel, and the first moving stroke and the second moving stroke of the inflation component 300 are realized by driving the piston rod to move.

[0064] It can be understood that, since the inflation channel 340 is extended along the first direction, the first inflation port 310 is connected to the end of the inflation channel 340 close to the air cavity 110, the second inflation port 330 is connected to the end of the inflation channel 340 away from the air cavity 110, and the second inflation port 330 is connected to the outside world. Therefore, the inflation gas can enter the first inflation port 310 through the second inflation port 330 and the inflation channel 340 in sequence. When the first inflation port 310 is located in the air cavity 110, it can enter the air cavity 110 through the first inflation port 310, and then pass through the air cavity 110. The opening of the third end 113 enters into the air suction pipe near the maintenance pump to prevent the working oil of the maintenance pump from flowing back into the air suction pipe under the action of atmospheric pressure, so as to avoid contamination of the air suction pipe. In this process, before the inflatable member 320 moves, since S5>S1+S2, it can ensure that the second inflating port 330 is always located outside the sealing through hole 131, so as to ensure that the second inflating port 330 is not always sealed by the sealing through hole 131, so as to ensure that the inflation gas can enter the inflation channel 340 through the second inflating port 330, so as to realize the inflation function of the air cavity 110.

[0065] Reference Figure 5As shown, the valve cover assembly 200 also includes an elastic support member 220, the valve cover 210 is provided with a receiving groove 212 opening toward the second end 112, the receiving groove 212 is extended along the first direction, the elastic support member 220 is arranged in the receiving groove 212, one end of the inflatable member 320 along the first direction is penetrated in the receiving groove 212, and the two ends of the elastic support member 220 along the first direction are respectively connected to the bottom of the receiving groove 212 and the inflatable member 320.

[0066] Specifically, in the above-mentioned embodiment, the elastic support member 220 is a spring.

[0067] It can be understood that since the valve cover 210 is provided with a receiving groove 212 opening toward the second end 112, the receiving groove 212 extends along the first direction, and one end of the inflatable member 320 along the first direction is inserted into the receiving groove 212, therefore, the inflatable member 320 can be moved in the receiving groove 212 relative to the valve cover 210 along the first direction, so that the inflatable member 320 performs a second movement stroke process. In this process, since the elastic support member 220 is arranged in the receiving groove 212, and the two ends of the elastic support member 220 along the first direction are respectively connected to the bottom of the receiving groove 212 and the inflatable member 320, therefore, the elastic support member 220 can support the inflatable member 320, thereby preventing the inflatable member 320 from moving relative to the valve cover 210 in the first movement stroke, thereby ensuring that the inflatable member 320 moves synchronously with the valve cover 210 in the first movement stroke.

[0068] The vacuum pumping equipment involved in the embodiment of the present application includes: the above-mentioned vacuum protection valve.

[0069] Specifically, in the above-mentioned embodiment, the vacuum protection valve is arranged on the air extraction pipeline between the oil diffusion pump and the maintenance pump.

[0070] In the above-mentioned vacuum pumping equipment, since the above-mentioned vacuum protection valve can simultaneously perform vacuum protection on the oil diffusion pump and break the vacuum of the exhaust pipe between the oil diffusion pump and the maintenance pump, the above-mentioned vacuum pumping equipment can achieve better vacuum pumping performance.

[0071] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0072] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A vacuum protection valve, characterized in that: include: A valve body assembly, wherein the valve body assembly is provided with an air cavity, wherein the air cavity has a first end, a second end and a third end which are arranged at intervals, wherein the first end is arranged in front of the second end along a first direction, and the first end, the second end and the third end are all provided with openings; a valve cover assembly, the valve cover assembly being movably disposed in the air cavity; An inflatable component, wherein the inflatable component is movably arranged in the air cavity through the opening of the second end, and the inflatable component is sealed and connected to the edge of the opening of the second end, the inflatable component is movably connected to the valve cover component, the inflatable component is provided with a first inflatable port, and in the first direction, the inflatable component has a first moving stroke and a second moving stroke which are performed successively; Among them, in the first moving stroke, the valve cover assembly moves synchronously with the inflation assembly and moves to be sealed against the cavity wall of the first end, and the first inflation port is located outside the air cavity. In the second moving stroke, the valve cover assembly is sealed against the cavity wall of the first end, and the first inflation port enters the air cavity through the second end.

2. The vacuum protection valve according to claim 1, characterized in that: The valve cover assembly comprises a valve cover, the valve body assembly comprises a valve body, the valve body is provided with the air cavity, and the valve cover is movably arranged in the air cavity.

3. The vacuum protection valve according to claim 2, characterized in that: In the second direction, a sealing portion is defined between the opening of the first end and the cavity wall of the air cavity, the valve cover has a sealing surface along the first direction, and the valve cover moves along the first direction so that the edge of the sealing surface abuts against the sealing portion; The second direction is perpendicular to the first direction, the opening of the first end has a diameter of L1, and the cavity diameter of the air cavity is L2, satisfying: L1<L2.

4. The vacuum protection valve according to claim 3, characterized in that: In the second direction, the minimum width of the sealing surface is L3, satisfying: L3≥L1, L3<L2.

5. The vacuum protection valve according to claim 2, characterized in that: The valve body assembly further comprises a cover plate disposed on the second end, the cover plate being provided with a sealing through hole extending along the first direction, one end of the sealing through hole being communicated with the air cavity through an opening of the second end, the inflatable assembly comprising an inflatable member, the inflatable member being movably disposed through the sealing through hole and being sealingly connected to a hole wall of the sealing through hole, the inflatable member being movably connected to the valve cover and being movable relative to the valve cover along the first direction; Among them, the first inflation port is opened on the inflatable member, and in the first direction, the inflatable member has the first movement stroke and the second movement stroke which are performed successively. In the first movement stroke, the first inflation port is located behind one end of the sealing through hole near the air cavity.

6. The vacuum protection valve according to claim 5, characterized in that: In the first direction, the distance of the first moving stroke is S1, the distance of the second moving stroke is S2, and before the inflatable member moves, the distance between the first inflation port and one end of the sealing through hole close to the air cavity is S3, satisfying: S1+S2≥S3, and S1<S3.

7. The vacuum protection valve according to claim 6, characterized in that: In the first direction, the valve cover assembly has a third movement stroke. In the third movement stroke, the valve cover assembly moves to seal against the cavity wall of the first end. The distance of the third movement stroke is S4, satisfying: S1+S2>S4.

8. The vacuum protection valve according to claim 6, characterized in that: The inflatable component is further provided with a second inflatable port and an inflatable channel, the second inflatable port and the inflatable channel are both provided on the inflatable member, the inflatable channel is extended along the first direction, the first inflatable port is communicated with an end of the inflatable channel close to the air cavity, and the second inflatable port is communicated with an end of the inflatable channel away from the air cavity; Wherein, before the inflatable member moves, the distance between the second inflatable port and the end of the sealing through hole away from the air cavity is S5, satisfying: S5>S1+S2.

9. The vacuum protection valve according to claim 5, characterized in that: The valve cover assembly also includes an elastic support member, the valve cover is provided with a receiving groove with an opening toward the second end, the receiving groove is extended along the first direction, the elastic support member is arranged in the receiving groove, one end of the inflatable member along the first direction is penetrated into the receiving groove, and the two ends of the elastic support member along the first direction are respectively connected to the bottom of the receiving groove and the inflatable member.

10. A vacuum pumping device, characterized in that: include: A vacuum protection valve as claimed in any one of claims 1 to 9.

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