CN216922418U

CN216922418U - Normally open air inlet valve

Info

Publication number: CN216922418U
Application number: CN202220314901.8U
Authority: CN
Inventors: 肖小万
Original assignee: Chongqing Kaishan Fluid Machinery Co ltd
Current assignee: Chongqing Kaishan Fluid Machinery Co ltd
Priority date: 2022-02-16
Filing date: 2022-02-16
Publication date: 2022-07-08
Anticipated expiration: 2032-02-16

Abstract

A normally open air inlet valve comprises a lower shell, an upper shell and a piston body, wherein the bottom of the lower shell is provided with a first connecting port, the top of the upper shell is provided with a second connecting port, an air cylinder body is arranged in the lower shell, an air flow channel is formed between the air cylinder body and the inner wall of the lower shell, the upper end of the air cylinder body is open and is sealed through an air cylinder cover, the cylinder cover is provided with a sleeve opening, the piston body is in sliding fit in the cylinder body, a return spring is arranged between the bottom surface of the piston body and the cylinder body, the top surface of the piston body is provided with a piston column, the piston column upwards passes through the sleeve opening of the cylinder cover to form sliding fit, the extending end of the piston column is fixedly connected with a valve block, and the second connecting hole is communicated with the cylinder body and is positioned below the piston body. The vacuum pumping head has the advantages of simple structure, convenience in maintenance, small air inlet compression of the vacuum pumping head and reliable performance.

Description

Normally open admission valve

Technical Field

The utility model relates to the field of valves, in particular to a normally open air inlet valve.

Background

The vacuum pump requires a mating inlet valve. Currently, the matched air inlet valves are divided into normally closed air inlet valves and normally open air inlet valves.

However, the initial pre-pressure of the return spring used with the normally closed intake valve is relatively large, which can ensure the sealing performance of the intake valve, but causes large pressure loss when the vacuum pump initially exhausts the atmosphere, and further causes small air exhaust amount of the vacuum pump. The conventional normally-open air inlet valve is easy to open and is not closed tightly, so that the problem of back suction of oil is caused.

Therefore, the problem to be solved by those skilled in the art is how to design an intake valve with small intake pressure loss and reliable performance.

Disclosure of Invention

The utility model aims to provide a normally open air inlet valve aiming at the defects of the prior art, which has the advantages of simple structure, convenient maintenance, small air inlet compression of a vacuumizing machine head and reliable performance.

The technical scheme of the utility model is as follows: a normally open air inlet valve comprises a lower shell, an upper shell and a piston body, wherein the lower shell and the upper shell are folded to form a whole, the bottom of the lower shell is provided with an opening to form a first connecting port connected with a vacuum pump head, the top of the upper shell is provided with an opening to form a second connecting port connected with a source to be vacuumized, the lower shell is internally provided with a cylinder body, a spacing space is formed between the cylinder body and the inner wall of the lower shell to form an air flow channel, the upper end of the cylinder body is open and is sealed by a cylinder cover, the cylinder cover is provided with a sleeve opening, the piston body is in sliding fit in the cylinder body, a reset spring is arranged between the bottom surface of the piston body and the cylinder body, the top surface of the piston body is provided with a piston column, the piston column upwards penetrates through the sleeve opening of the cylinder cover to form sliding fit, and an extending end of the piston column is fixedly connected with a valve block to form sealing fit with the second connecting port of the upper shell, the lower shell is provided with a first communicating hole which is communicated with the cylinder body and is positioned above the piston body, and the lower shell is provided with a second communicating hole which is communicated with the cylinder body and is positioned below the piston body.

The upper shell and the lower shell are fixedly connected through a plurality of bolts to form a whole.

The cylinder cover and the cylinder block are fixedly connected through a plurality of bolts.

The bottom surface of the piston body is provided with a positioning groove, the lower end of the return spring is abutted against the cylinder bottom of the cylinder body, and the upper end of the return spring is limited by the positioning groove.

A first sealing ring is arranged between the piston body and the cylinder body.

And a second sealing ring is arranged between the sleeve opening and the piston column.

And a third sealing ring is arranged between the cylinder cover and the cylinder block.

And a fourth sealing ring is arranged between the upper shell and the lower shell.

The extension end of the piston column is provided with an assembly step, and the valve block is installed on the assembly step and locked through a nut.

And a gasket is arranged in front of the valve plate and the nut.

Adopt above-mentioned technical scheme to have following beneficial effect:

1. the normally open air inlet valve comprises a lower shell, an upper shell and a piston body, and the lower shell and the upper shell are folded to form a whole. The bottom of casing is equipped with the opening down, forms the first interface that is used for being connected with the vacuum pump aircraft nose, the top of going up the casing is equipped with the opening, forms and is used for and treats the second connector that the evacuation source is connected, promptly, the vacuum pump aircraft nose through the casing inner space of normally opening admission valve with treat the evacuation source and be connected, when this casing inner space is unobstructed, the vacuum pump aircraft nose with treat the evacuation source and be in the connected state, when this casing inner space is cut off, the vacuum pump aircraft nose with treat the evacuation source and be in the off-state. The lower shell is internally provided with a cylinder body, a space is formed between the cylinder body and the inner wall of the lower shell to form an airflow channel, namely, the first connecting port and the second connecting port are connected through the airflow channel. The upper end of the cylinder body is open and is sealed through the cylinder cover, the cylinder cover is provided with a sleeve opening, the piston body is in sliding fit in the cylinder body, a reset spring is arranged between the bottom surface of the piston body and the cylinder body, the top surface of the piston body is provided with a piston column, the piston column upwards penetrates through the sleeve opening of the cylinder cover to form sliding fit, the extending end of the piston column is fixedly connected with the valve block and forms sealing fit with the second connecting opening of the upper shell, namely, the valve block is matched with the second connecting opening to open or close the airflow channel. The lower shell is provided with a first communicating hole which is communicated with the cylinder body and is positioned above the piston body, and the lower shell is provided with a second communicating hole which is communicated with the cylinder body and is positioned below the piston body. Generally, the first communication hole is communicated with the atmosphere, the second communication hole is communicated with the vacuum pump head, when the vacuum pump head is in loading operation, namely, the vacuum pump head forms negative pressure, the bottom surface of the piston body is negative pressure, the top surface of the piston body is atmospheric pressure and has differential pressure, the piston body moves downwards, the reset spring is compressed, meanwhile, the valve sheet is separated from the second connection port, the first connection port is communicated with the second connection port, the normally open air inlet valve is in an open state, and the vacuum pump head performs vacuum pumping operation on a vacuum source to be pumped; when the vacuum pump head is unloaded or stops running, the vacuum pump head is recovered to atmospheric pressure, no pressure difference exists between the top surface and the bottom surface of the piston body, the valve block is reset under the action of the reset spring, the air flow channel is closed, the first connecting port and the second connecting port are disconnected, and the top surface and the bottom surface of the valve block have pressure difference due to the fact that the vacuum source to be pumped is in a negative pressure state, the valve block is tightly pressed on the second connecting port under the dual effects of the reset spring and the differential pressure, sealing matching is formed, and the stability of the air inlet valve can be effectively guaranteed.

2. The bottom surface of the piston body is provided with a positioning groove, the lower end of the reset spring is abutted against the cylinder bottom of the cylinder body, the upper end of the reset spring is limited by the positioning groove, the stability of the reset spring is guaranteed, and the long-time normal operation of the normally-open air inlet valve is further guaranteed.

3. The extension end of piston post is equipped with the assembly step, the valve block is installed on the assembly step, and locks through the nut, guarantees the connection stability between valve block and the piston post, and then guarantees the long-time normal operation of normally opening the admission valve.

The following further description is made with reference to the accompanying drawings and detailed description.

Drawings

FIG. 1 is a schematic structural view of the present invention;

fig. 2 is a sectional view taken along line a-a of fig. 1.

In the drawing, 1 is a lower casing, 2 is an upper casing, 3 is a piston body, 4 is a first connecting port, 5 is a second connecting port, 6 is a cylinder body, 7 is an air flow channel, 8 is a cylinder cover, 9 is a sleeve opening, 10 is a return spring, 11 is a piston column, 12 is a valve plate, 13 is a first communicating hole, 14 is a second communicating hole, 15 is a positioning groove, and 16 is a gasket.

Detailed Description

Referring to fig. 1 and 2, an embodiment of a normally open intake valve is shown. The normally open air inlet valve comprises a lower shell 1, an upper shell 2 and a piston body 3. The lower shell 1 and the upper shell 2 are folded to form a whole, in this embodiment, the upper shell and the lower shell are connected to form a whole by penetrating through a flange plate through a plurality of bolts, and a fourth sealing ring is arranged between the upper shell and the lower shell flange plate. The bottom of the lower shell 1 is provided with an opening to form a first connecting port 4 for connecting with a vacuum pump head. The top of the upper shell 2 is provided with an opening to form a second connecting port 5 for connecting with a source to be vacuumized, and usually, a flange plate is required to be arranged on the first connecting port, and a flange plate is arranged on the second connecting port, so that the upper shell can be conveniently connected with an opponent. The lower shell 1 is internally provided with a cylinder body 6, an interval space is arranged between the cylinder body 6 and the inner wall of the lower shell 1 to form an airflow channel 7, the upper end of the cylinder body 6 is open and is sealed by a cylinder cover 8, a sleeve opening 9 is arranged on the cylinder cover 8, specifically, the cylinder body is arranged in the middle of the lower shell, the upper part of an inner cavity of the cylinder body is cylindrical, the lower part of the inner cavity of the cylinder body is in an inverted round table shape, and the cylinder cover 8 is fixedly connected with the cylinder body 6 through a plurality of bolts. The piston body 3 is in sliding fit with the upper portion of the cylinder body, a return spring 10 is arranged between the bottom surface of the piston body 3 and the cylinder body, and a piston column 11 is arranged on the top surface of the piston body 3. The piston post 11 upwards passes the cover mouth 9 of cylinder head, forms sliding fit, and the extension end fixed connection valve block 12 of piston post 11 forms sealed cooperation with the second connector 5 of last casing, and in this embodiment, be equipped with the second sealing washer between cover mouth 9 and the piston post 11, be equipped with the third sealing washer between cylinder head 8 and the cylinder body 6, the extension end of piston post 11 is equipped with the assembly step, valve block 12 is installed on the assembly step, and locks through the nut, and is specific, is equipped with gasket 16 before valve block 12 and the nut. The lower shell 1 is provided with a first communicating hole 13 which is communicated with the cylinder block 6 and is positioned above the piston body 3, and the lower shell 1 is provided with a second communicating hole 14 which is communicated with the cylinder block 6 and is positioned below the piston body 3.

The working principle of the utility model is that the first communication hole is provided with an electromagnetic three-way valve which is respectively connected with atmosphere or a source to be vacuumized, and the second communication hole is provided with an electromagnetic three-way valve which is respectively connected with atmosphere or a vacuum pump head. The normally open air inlet valve is connected with a vacuum pump head through a first connector and is connected with a to-be-vacuumized source through a second connector, when the vacuum pump head is in loading operation, a first communication hole of the normally open air inlet valve is communicated with the atmosphere, a second communication hole is communicated with the vacuum pump head, the vacuum pump head forms negative pressure, the bottom surface of the piston body is negative pressure, the top surface of the piston body is atmospheric pressure and has differential pressure, the piston body moves downwards, the reset spring is compressed, meanwhile, the valve block is separated from the second connector, the first connector is communicated with the second connector, the normally open air inlet valve is in an open state, and the vacuum pump head conducts vacuumization operation on the to-be-vacuumized source; when the vacuum pump aircraft nose is in the uninstallation state (vacuum pump aircraft nose low-speed operation, be in vacuum state, treat that the evacuation source is in vacuum state), the first intercommunicating pore of the normally open admission valve of control links to each other with treating the evacuation source, and the second intercommunicating pore is connected with the atmosphere, and the top surface of piston body is negative pressure (vacuum), and the bottom surface of piston body is atmospheric pressure, has pressure differential, and the piston body upwards acts, and the normally open admission valve is closed. When the machine head of the vacuum pump is shut down, the first communication hole of the normally open air inlet valve is controlled to be connected with a source to be vacuumized, the second communication hole is communicated with the atmosphere, the machine head of the vacuum pump recovers to the atmospheric pressure, if the source to be vacuumized is also the atmospheric pressure, no pressure difference exists, and no risk of reverse pumping exists; if the vacuum source to be pumped is in a vacuum state, the top surface of the piston body is in negative pressure (vacuum), the bottom surface of the piston body is in atmospheric pressure and has differential pressure, the piston body moves upwards, and the normally-open air inlet valve is closed.

Claims

1. A normally open admission valve, its characterized in that: comprises a lower shell (1), an upper shell (2) and a piston body (3), wherein the lower shell (1) and the upper shell (2) are folded to form a whole,

the bottom of the lower shell (1) is provided with an opening to form a first connecting port (4) for connecting with a vacuum pump head,

the top of the upper shell (2) is provided with an opening to form a second connecting port (5) for connecting with a source to be vacuumized,

the lower shell (1) is internally provided with a cylinder body (6), an interval space is arranged between the cylinder body (6) and the inner wall of the lower shell (1) to form an airflow channel (7), the upper end of the cylinder body (6) is open and is sealed by a cylinder cover (8), the cylinder cover (8) is provided with a sleeve opening (9),

the piston body (3) is in sliding fit in the cylinder body (6), a return spring (10) is arranged between the bottom surface of the piston body (3) and the cylinder body, a piston column (11) is arranged on the top surface of the piston body (3), the piston column (11) upwards penetrates through a sleeve opening (9) of the cylinder cover to form sliding fit, a valve sheet (12) is fixedly connected with the extending end of the piston column (11) to form sealing fit with a second connecting opening (5) of the upper shell,

the lower shell (1) is provided with a first communicating hole (13) which is communicated with the cylinder body (6) and is positioned above the piston body (3),

the lower shell (1) is provided with a second communicating hole (14), is communicated with the cylinder body (6) and is positioned below the piston body (3).

2. The normally open intake valve of claim 1, wherein: the upper shell (2) and the lower shell (1) are fixedly connected through a plurality of bolts to form a whole.

3. The normally open intake valve of claim 1, wherein: the cylinder cover (8) and the cylinder block (6) are fixedly connected through a plurality of bolts.

4. The normally open intake valve of claim 1, wherein: the bottom surface of the piston body (3) is provided with a positioning groove (15), the lower end of the return spring (10) is abutted against the cylinder bottom of the cylinder body (6), and the upper end of the return spring (10) is limited by the positioning groove (15).

5. The normally open intake valve of claim 1, wherein: a first sealing ring is arranged between the piston body (3) and the cylinder body (6).

6. The normally open intake valve of claim 1, wherein: and a second sealing ring is arranged between the sleeve opening (9) and the piston column (11).

7. The normally open intake valve of claim 1, wherein: and a third sealing ring is arranged between the cylinder cover (8) and the cylinder block (6).

8. The normally open intake valve of claim 1, wherein: and a fourth sealing ring is arranged between the upper shell (2) and the lower shell (1).

9. The normally open intake valve of claim 1, wherein: the extension end of the piston column (11) is provided with an assembly step, and the valve plate (12) is installed on the assembly step and locked through a nut.

10. A normally open intake valve as defined in claim 9, wherein: a gasket (16) is arranged in front of the valve plate (12) and the nut.