CN210978605U - Impact-resistant vacuum interface valve - Google Patents
Impact-resistant vacuum interface valve Download PDFInfo
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- CN210978605U CN210978605U CN201920958575.2U CN201920958575U CN210978605U CN 210978605 U CN210978605 U CN 210978605U CN 201920958575 U CN201920958575 U CN 201920958575U CN 210978605 U CN210978605 U CN 210978605U
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Abstract
The utility model discloses a vacuum interface valve that shocks resistance, including the valve body and be located the piston diaphragm of valve body, be provided with first entry and first export, its characterized in that on the valve body: the piston diaphragm is provided with a damping cavity; the vacuum interface valve also comprises a damping system and a vacuum driving system; the damping system comprises damping liquid, a damping liquid chamber, a first one-way valve and a second one-way valve; a driving diaphragm is arranged in the vacuum driving system and is fixedly connected with the piston diaphragm through a connecting rod; the damping cavity is filled with the damping liquid. The utility model provides a piston diaphragm in the vacuum interface valve has the characteristics of shocking resistance, can promote piston diaphragm's life, and then improves the reliability of interface valve.
Description
[ technical field ] A method for producing a semiconductor device
The utility model relates to a technical field of valve especially relates to an interface valve that shocks resistance.
[ background of the invention ]
In the field of drainage, a stepped valve core or a tapered valve core is adopted in the prior art to slide in a valve body, so that the opening or closing of fluid is realized, but in the field of vacuum drainage, the conventional valve core and the valve body have no ideal effect in the aspects of corresponding speed, sealing performance, reliability and the like.
However, in the prior art vacuum interface valve, due to the fast switching speed between the vacuum in the vacuum chamber and the standard atmospheric pressure, the piston diaphragm in the interface valve is strongly impacted when being opened and closed, which is very easy to cause fatigue damage of the piston diaphragm, and reduces the reliability of the interface valve.
Therefore, there is a need to develop a vacuum interface valve that is resistant to impact.
[ Utility model ] content
The utility model aims at solving the problem among the prior art, provide a vacuum interface valve, the piston diaphragm in the vacuum interface valve has the characteristics of shocking resistance, can promote piston diaphragm's life, and then improves the reliability of interface valve.
In order to achieve the above object, the utility model provides a vacuum interface valve that shocks resistance, include the valve body and be located the piston diaphragm of valve body, be provided with first export and first entry on the valve body, its characterized in that: an opening at the upper end of the piston diaphragm is hermetically connected with the top wall of the valve body to form a closed damping cavity; the vacuum interface valve further comprises a damping system and a vacuum drive system; the damping system comprises damping liquid, a damping liquid chamber for storing the damping liquid, and a first one-way valve and a second one-way valve for controlling the flow direction of the damping liquid; a driving diaphragm is arranged in the vacuum driving system and is fixedly connected with the piston diaphragm through a connecting rod; the damping chamber is filled with the damping fluid, when the piston diaphragm expands for cutting off the first outlet and the first inlet, the damping fluid flows into the damping chamber from the damping fluid chamber through the first check valve, and when the piston diaphragm contracts for communicating the first outlet and the first inlet, the damping fluid flows back to the damping fluid chamber from the damping chamber through the second check valve.
Preferably, the piston diaphragm is annular, the bottom of the piston diaphragm is inwards concave to form a bottom inner cavity, the circumferential side wall of the piston diaphragm is inwards concave to form a C-shaped cross section, the outer diameter of the upper end and the outer diameter of the lower end of the piston diaphragm are larger than the inner diameter of the outer wall of the middle of the piston diaphragm, the center of the bottom inner cavity is provided with an integrally formed cylindrical pipe wall, and the side wall of the bottom inner cavity is provided with reinforcing ribs.
Preferably, the top of the bottom inner cavity of the piston diaphragm is provided with an annular pressure plate, the annular pressure plate is sleeved on the connecting rod, the top of the annular pressure plate abuts against a step on the connecting rod, and the bottom of the annular pressure plate abuts against the upper end wall surface of the bottom inner cavity; the lower end of the connecting rod penetrates through the wall of the cylindrical pipe, a locking nut is further arranged at the lower end of the connecting rod, and the locking nut and the step of the connecting rod limit the axial freedom degree of the annular pressing plate and the piston diaphragm together.
Preferably, a flexible throat hoop is sleeved on the middle section of the circumferential side wall of the piston diaphragm to prevent the circumferential side wall of the piston diaphragm from expanding due to the lateral pressure of the damping fluid.
Preferably, the damping liquid chamber is hermetically fixed on the top of the valve body, and the first check valve and the second check valve are both arranged on the top wall of the valve body; an inlet of the first one-way valve is positioned in the damping liquid chamber, and an outlet of the first one-way valve is communicated with the damping cavity; and the outlet of the second one-way valve is positioned in the damping liquid chamber, and the inlet of the second one-way valve is communicated with the damping cavity.
Preferably, the vacuum driving system further comprises a vacuum driving chamber, the driving diaphragm is located in an inner cavity of the vacuum driving chamber, and the inner cavity of the vacuum driving chamber is isolated into a first driving cavity located at the upper part of the driving diaphragm and a second driving cavity located at the lower part of the driving diaphragm, and the first driving cavity and the second driving cavity are respectively connected with the vacuum generator through a first air pipe and a second air pipe; the lower part of the driving diaphragm is also provided with a return spring, the return spring is sleeved on the connecting rod, the upper end of the return spring is propped against the driving diaphragm, and the lower end of the return spring is propped against the bottom wall of the second driving cavity.
Preferably, the top center of the valve body is provided with a cavity opening, the cavity opening is hermetically connected with a plug cover, the connecting rod penetrates through the plug cover, and a movable sealing ring is arranged between the connecting rod and the plug cover.
Preferably, the inner side surface of the bottom wall of the valve body is a spherical wall surface, the first inlet is located in the center of the bottom wall of the valve body, the first outlet is located on the cylindrical side wall of the valve body, and when the piston diaphragm expands and moves down to the bottom of the valve body, the piston diaphragm is tightly attached to the spherical wall surface of the bottom of the valve body.
The utility model has the advantages that: the utility model discloses a set up damping system, pack damping liquid in the piston diaphragm to the process that makes piston diaphragm's shrink shift up or the inflation move down all receives fluid damping's effect, prevents to cause piston diaphragm's strong impact under the vacuum effect, therefore can prolong piston diaphragm's life, improves vacuum diaphragm valve's reliability.
The features and advantages of the present invention will be described in detail by embodiments with reference to the accompanying drawings.
[ description of the drawings ]
Fig. 1 is a cross-sectional view of the overall structure of the present invention.
In the figure: 1-valve body, 2-piston diaphragm, 3-damping system, 4-vacuum driving system, 5-plug cover, 6-connecting rod, 7-annular pressure plate, 8-damping cavity, 101-first outlet, 102-first inlet, 103-spherical wall surface, 201-circumferential side wall, 202-flexible throat hoop, 203-cylindrical tube wall, 204-reinforcing rib, 205-bottom inner cavity, 301-damping liquid chamber, 302-first check valve, 303-second check valve, 401-driving diaphragm, 402-first driving cavity, 403-second driving cavity, 404-reset spring, 405-first air pipe and 406-second air pipe.
[ detailed description ] embodiments
Referring to fig. 1, the present invention relates to a shock-resistant vacuum interface valve, including a valve body 1 and a piston diaphragm 2 located in the valve body, the valve body is provided with a first outlet 101 and a first inlet 102, and is characterized in that: an opening at the upper end of the piston diaphragm is hermetically connected with the top wall of the valve body to form a closed damping cavity 8; the vacuum interface valve further comprises a damping system 3 and a vacuum driving system 4; the damping system comprises damping liquid, a damping liquid chamber 301 for storing the damping liquid, and a first check valve 302 and a second check valve 303 for controlling the flow direction of the damping liquid; a driving diaphragm 401 is arranged in the vacuum driving system, and the driving diaphragm is fixedly connected with the piston diaphragm through a connecting rod 6; the damping chamber is filled with the damping fluid, when the piston diaphragm expands for cutting off the first outlet and the first inlet, the damping fluid flows into the damping chamber from the damping fluid chamber through the first check valve, and when the piston diaphragm contracts for communicating the first outlet and the first inlet, the damping fluid flows back to the damping fluid chamber from the damping chamber through the second check valve.
The piston diaphragm 2 is annular, the bottom of the piston diaphragm is inwards concave to form a bottom inner cavity 205, the circumferential side wall 201 of the piston diaphragm is inwards concave to form a C-shaped cross section, the outer diameters of the upper end and the lower end of the piston diaphragm are larger than the inner diameter of the outer wall of the middle part of the piston diaphragm, the center of the bottom inner cavity is provided with a cylindrical pipe wall 203 integrally formed with the piston diaphragm, and the side wall of the bottom inner cavity is provided with a reinforcing rib 204. The reinforcing rib is used for providing support for the bottom wall surface of the piston diaphragm, so that the bottom wall surface of the piston diaphragm can keep certain structural strength when bearing the push-pull action of the connecting rod 6, and the whole piston diaphragm can quickly respond to the action of the connecting rod.
The top of the bottom inner cavity of the piston diaphragm 2 is provided with an annular pressure plate 7 which is sleeved on the connecting rod 6, the top of the annular pressure plate props against a step on the connecting rod, and the bottom of the annular pressure plate props against the upper end wall surface of the bottom inner cavity 205; the lower end of the connecting rod penetrates through the cylindrical pipe wall 203, a locking nut is further arranged at the lower end of the connecting rod, and the locking nut and the step of the connecting rod limit the axial freedom degrees of the annular pressing plate 7 and the piston diaphragm 2 together
The middle section of the circumferential side wall 201 of the piston diaphragm 2 is sleeved with a flexible throat hoop 202, so that the circumferential side wall of the piston diaphragm is prevented from expanding due to the lateral pressure of the damping fluid.
The damping liquid chamber 301 is hermetically fixed at the top of the valve body 1, and the first one-way valve 302 and the second one-way valve 303 are both arranged on the top wall of the valve body; an inlet of the first one-way valve is positioned in the damping liquid chamber, and an outlet of the first one-way valve is communicated with the damping cavity; and the outlet of the second one-way valve is positioned in the damping liquid chamber, and the inlet of the second one-way valve is communicated with the damping cavity.
The vacuum driving system 4 further comprises a vacuum driving chamber, the driving diaphragm 401 is located in an inner cavity of the vacuum driving chamber, and the inner cavity of the vacuum driving chamber is isolated into a first driving cavity 402 located at the upper part of the driving diaphragm and a second driving cavity 403 located at the lower part of the driving diaphragm, and the first driving cavity and the second driving cavity are respectively connected with a vacuum generator through an air pipe 405; the lower part of the driving diaphragm is also provided with a return spring 404, the return spring is sleeved on the connecting rod 6, the upper end of the return spring props against the driving diaphragm, and the lower end of the return spring props against the bottom wall of the second driving cavity.
The top center of valve body 1 is provided with the accent, sealing connection has gag 5 on the accent, connecting rod 6 passes the gag, and be provided with between connecting rod and the gag and move the sealing ring, the connecting rod need be circumferential movement for the gag promptly, moves the sealing ring and is in order to guarantee the in-process that the connecting rod reciprocated, and the damping liquid that is arranged in the damping chamber can not flow out from the contact surface of connecting rod and gag.
The inner side surface of the bottom wall of the valve body 1 is a spherical wall surface 103, the first inlet is positioned in the center of the bottom wall of the valve body, the first outlet is positioned on the cylindrical side wall of the valve body, and when the piston diaphragm 2 expands and moves downwards to the bottom of the valve body under the downward thrust of the connecting rod, the piston diaphragm is tightly attached to the spherical wall surface 103 at the bottom of the valve body, so that the bottom of the piston diaphragm is provided with a conical bottom surface.
The top end of the connecting rod is fixedly connected with the driving diaphragm, as shown in fig. 1, a gasket is respectively arranged on the upper surface and the lower surface of the central point of the driving diaphragm 401, then a screw penetrates through the centers of the gasket and the driving diaphragm, a threaded hole is formed in the top end face of the connecting rod, and the screw is screwed on the end portion of the connecting rod.
The bottom end of the connecting rod is fixedly connected with the bottom of the piston diaphragm 2, and as shown in fig. 1, the lower end of the connecting rod penetrates through the cylindrical pipe wall 203 from top to bottom, and the bottom of the piston diaphragm 2 is locked on the lower end of the connecting rod in a double-nut anti-loose mode.
The vacuum driving chamber shown in fig. 1 includes an upper chamber body and a lower chamber body, a sealing ring is disposed between the upper chamber body and the lower chamber body, and the outer circumferential edge of the driving diaphragm is also located on a joint surface between the upper chamber body and the lower chamber body, and the upper chamber body and the lower chamber body are fixedly connected by screws.
As shown in fig. 1, the vacuum driving system 4 is fixedly connected to the valve body 1 through a bracket.
As shown in fig. 1, the passage between the first check valve 302 and the damping chamber 8 is formed by a deep hole on the top wall surface of the valve body 1, a ring groove on the side wall of the plug cover 5 and the deep hole; and the passage between the second check valve 303 and the damping chamber 8 is formed by a deep hole in the top of the valve body 1.
The damping fluid may be a fluid medium such as water or hydraulic oil.
The utility model discloses the working process:
1) and (5) closing process. A first air pipe 405 communicated with the first driving cavity 402 is communicated with standard atmospheric pressure, and a second air pipe 406 communicated with the second driving cavity 403 is communicated with vacuum negative pressure, because the atmospheric pressure in the first driving cavity 402 is greater than the atmospheric pressure in the second driving cavity 403, and because the circumferential outer edge of the driving diaphragm is hermetically fixed on the side wall of the vacuum driving chamber, the outer edge of the driving diaphragm is fixed, and the center of the driving diaphragm moves downwards against the elastic resistance of a return spring 404; the top end of the connecting rod 6 is fixedly connected with the center of the driving diaphragm, so that the connecting rod is pushed by the driving diaphragm to move downwards, and the bottom end of the connecting rod 6 is fixedly connected with the bottom of the piston diaphragm 2, so that the connecting rod 6 pushes the bottom of the piston diaphragm 2 to move downwards until the bottom wall of the piston diaphragm 2 is tightly attached to the spherical wall surface 103 at the bottom of the valve body 1 to achieve stress balance; before the bottom of the piston diaphragm 2 moves downwards, the damping cavity 8 is filled with damping fluid, when the bottom of the piston diaphragm 2 moves downwards, negative pressure is formed in the damping cavity 8 due to the increase of the volume of the damping cavity 8, the first one-way valve 302 is forced to be conducted due to pressure difference, the damping fluid in the damping fluid chamber 301 flows into the damping cavity 8 through the first one-way valve 302, and the flow resistance borne by the damping fluid flowing into the damping cavity 8 from the damping fluid chamber 301 is the buffering damping force borne by the piston diaphragm 2 when the first outlet 101 and the first inlet 102 of the valve body 1 are cut off and closed.
2) And (5) starting the process. Contrary to the closing process, a first air pipe 405 communicated with the first driving cavity 402 is communicated with vacuum negative pressure, and a second air pipe 406 communicated with the second driving cavity 403 is communicated with standard atmospheric pressure, so that the outer edge of the driving diaphragm 401 is fixed, and the center of the driving diaphragm moves upwards under the action of the elastic force of the return spring 404 and the pressure difference in the vacuum driving cavity; the connecting rod 6 drives the bottom of the piston diaphragm 2 to move upwards, the curvature of the cylindrical side wall 201 is increased, and the volume in the damping cavity 8 is reduced, so that the damping liquid in the damping cavity 8 overcomes the second check valve 303 and flows back to the damping liquid chamber 301, and similarly, the flow resistance of the damping liquid in the process of flowing back to the damping liquid chamber 301 from the damping cavity 8 is the buffering damping force applied to the piston diaphragm 2 when the first outlet 101 and the first inlet 102 of the valve body 1 are communicated.
3) And (5) pressure loss process. When the vacuum generator fails, the first air pipe 405 and the second air pipe 406 are both communicated with the atmospheric pressure, at this time, the pressures of the first driving cavity 402 and the second driving cavity 403 are the same, no matter whether the driving diaphragm 401 is positioned at the top or the bottom of the vacuum driving chamber, the driving diaphragm 401 moves to the middle position of the vacuum driving chamber under the action of the return spring 404, when the driving diaphragm 401 moves to the middle position of the vacuum driving chamber, the driving diaphragm is approximately in a natural state, the bottom of the piston diaphragm 2 moves to a position which is equal to the axial line of the first outlet 101, at this time, the first outlet 101 and the first inlet 102 are in a half-open state, and the communication of the valve body 1 is not influenced when the vacuum generator fails.
The utility model discloses a set up damping system, pack damping liquid in the piston diaphragm to the process that makes piston diaphragm's shrink shift up or the inflation move down all receives fluid damping's effect, prevents to cause piston diaphragm's strong impact under the vacuum effect, therefore can prolong piston diaphragm's life, improves vacuum diaphragm valve's reliability.
The above-mentioned embodiment is right the utility model discloses an explanation, it is not right the utility model discloses a limited, any right the scheme after the simple transform of the utility model all belongs to the protection scope of the utility model.
Claims (8)
1. An impact resistant vacuum interface valve comprising a valve body and a piston diaphragm located within the valve body, the valve body having a first outlet and a first inlet disposed thereon, the impact resistant vacuum interface valve characterized by: an opening at the upper end of the piston diaphragm is hermetically connected with the top wall of the valve body to form a closed damping cavity; the vacuum interface valve further comprises a damping system and a vacuum drive system; the damping system comprises damping liquid, a damping liquid chamber for storing the damping liquid, and a first one-way valve and a second one-way valve for controlling the flow direction of the damping liquid; a driving diaphragm is arranged in the vacuum driving system and is fixedly connected with the piston diaphragm through a connecting rod; the damping chamber is filled with the damping fluid, when the piston diaphragm expands for cutting off the first outlet and the first inlet, the damping fluid flows into the damping chamber from the damping fluid chamber through the first check valve, and when the piston diaphragm contracts for communicating the first outlet and the first inlet, the damping fluid flows back to the damping fluid chamber from the damping chamber through the second check valve.
2. The impact resistant vacuum interface valve of claim 1 wherein: the piston diaphragm is annular, and its bottom upwards indent forms the bottom inner chamber, the circumference lateral wall indent of piston diaphragm is C type cross-section, makes the external diameter at its upper and lower both ends be greater than the outer wall internal diameter of middle department, the center of bottom inner chamber is provided with integrated into one piece's cylinder pipe wall, be provided with the strengthening rib on the lateral wall of bottom inner chamber.
3. The impact resistant vacuum interface valve of claim 2 wherein: the top of the bottom inner cavity of the piston diaphragm is provided with an annular pressing plate, the annular pressing plate is sleeved on the connecting rod, the top of the annular pressing plate abuts against a step on the connecting rod, and the bottom of the annular pressing plate abuts against the upper end wall surface of the bottom inner cavity; the lower end of the connecting rod penetrates through the wall of the cylindrical pipe, a locking nut is further arranged at the lower end of the connecting rod, and the locking nut and the step of the connecting rod limit the axial freedom degree of the annular pressing plate and the piston diaphragm together.
4. The impact resistant vacuum interface valve of claim 2 wherein: the middle section of the circumferential side wall of the piston diaphragm is sleeved with a flexible hose clamp to prevent the circumferential side wall of the piston diaphragm from expanding due to the lateral pressure of the damping fluid.
5. The impact resistant vacuum interface valve of claim 1 wherein: the damping liquid chamber is fixed at the top of the valve body in a sealing manner, and the first one-way valve and the second one-way valve are arranged on the top wall of the valve body; an inlet of the first one-way valve is positioned in the damping liquid chamber, and an outlet of the first one-way valve is communicated with the damping cavity; and the outlet of the second one-way valve is positioned in the damping liquid chamber, and the inlet of the second one-way valve is communicated with the damping cavity.
6. The impact resistant vacuum interface valve of claim 1 wherein: the vacuum driving system also comprises a vacuum driving chamber, the driving diaphragm is positioned in an inner cavity of the vacuum driving chamber, and the inner cavity of the vacuum driving chamber is isolated into a first driving cavity positioned at the upper part of the driving diaphragm and a second driving cavity positioned at the lower part of the driving diaphragm, and the first driving cavity and the second driving cavity are respectively connected with a vacuum generator through a first air pipe and a second air pipe; the lower part of the driving diaphragm is also provided with a return spring, the return spring is sleeved on the connecting rod, the upper end of the return spring is propped against the driving diaphragm, and the lower end of the return spring is propped against the bottom wall of the second driving cavity.
7. The impact resistant vacuum interface valve of claim 1 wherein: the top center of valve body is provided with the accent, sealing connection has the gag on the accent, the connecting rod passes the gag, and is provided with between connecting rod and the gag and moves the sealing ring.
8. The impact resistant vacuum interface valve of claim 1 wherein: the inner side surface of the bottom wall of the valve body is a spherical wall surface, the first inlet is positioned in the center of the bottom wall of the valve body, the first outlet is positioned on the cylindrical side wall of the valve body, and when the piston diaphragm expands and moves downwards to the bottom of the valve body, the piston diaphragm is tightly attached to the spherical wall surface at the bottom of the valve body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920958575.2U CN210978605U (en) | 2019-06-25 | 2019-06-25 | Impact-resistant vacuum interface valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920958575.2U CN210978605U (en) | 2019-06-25 | 2019-06-25 | Impact-resistant vacuum interface valve |
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| Publication Number | Publication Date |
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| CN210978605U true CN210978605U (en) | 2020-07-10 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201920958575.2U Active CN210978605U (en) | 2019-06-25 | 2019-06-25 | Impact-resistant vacuum interface valve |
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| CN (1) | CN210978605U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110319233A (en) * | 2019-06-25 | 2019-10-11 | 浙江广播电视大学 | A kind of shock proof vacuum interface valve |
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2019
- 2019-06-25 CN CN201920958575.2U patent/CN210978605U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110319233A (en) * | 2019-06-25 | 2019-10-11 | 浙江广播电视大学 | A kind of shock proof vacuum interface valve |
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