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CN-122014864-A - Vacuum butterfly valve

CN122014864ACN 122014864 ACN122014864 ACN 122014864ACN-122014864-A

Abstract

The invention discloses a vacuum butterfly valve, which aims to solve the problems of more particles, poor reliability and no self-locking of the traditional butterfly valve. The vacuum butterfly valve comprises a cylinder assembly, a valve core assembly and a valve body. A piston is arranged in the cylinder assembly, and first, second and third tracks with different geometric shapes are machined on the surface of the piston. The special-shaped screw fixed on the cylinder barrel is matched with the first track and the second track on the outer surface of the piston to restrain the piston to generate linear and rotary compound motion. The roller at the head end of the connecting rod is matched with a third track on the inner surface of the piston, so that the compound motion of the piston is converted into the specific motion of the connecting rod. The connecting rod drives the valve core to sequentially execute the compound actions of separating from the valve seat, rotating by 90 degrees to open/close and then pressing the valve seat. In the fully open/fully closed position of the valve, the specific geometric shape of the third track enables the acting force direction to be perpendicular to the piston moving direction, and the mechanical self-locking of the gas interruption is realized.

Inventors

  • GUO YUXIAO
  • WEI QIONGLIN
  • ZHENG WENCAI
  • WANG LIANJI
  • ZHOU SIYAO
  • SHI WANTAO

Assignees

  • 成都中科唯实仪器有限责任公司

Dates

Publication Date
20260512
Application Date
20260313

Claims (10)

  1. 1. A vacuum butterfly valve comprises a cylinder assembly (1), a valve core assembly (2) and a valve body (3), wherein a valve core (201) of the valve core assembly (2) is arranged in the valve body (3), and the vacuum butterfly valve is characterized in that the cylinder assembly (1) comprises a cylinder barrel (102), a piston (104), a connecting rod (107) and a drive conversion mechanism, the piston (104) is movably arranged in the cylinder barrel (102), a plurality of tracks which are configured into different geometric shapes are arranged on the inner surface and the outer surface of the piston, the drive conversion mechanism comprises a fixing piece fixed to the cylinder barrel (102) and a driven piece connected to the connecting rod (107), the fixing piece is matched with at least one track on the outer surface of the piston (104) and used for restraining the piston (104) to generate output motion which is compounded with the rotation motion around the axis of the piston, the driven piece is matched with at least one other track on the inner surface of the piston (104) and used for converting the compound output motion of the piston (104) into the motion of the connecting rod (107), one end of the connecting rod (107) is connected with the driven piece, and the driven piece is connected with the other end of the driven piece to the other end of the connecting rod (107) so as to drive the valve core (201) to be separated from the valve seat to be driven to perform the rotation.
  2. 2. A vacuum butterfly valve according to claim 1, wherein the plurality of tracks of the piston (104) surface comprises a first track (401) and a second track (402) provided on its outer cylindrical surface, and a third track (403) provided on its inner cylindrical surface, wherein the fixing member is a profiled screw (103) passing through the cylinder (102) and cooperating with the first track (401) and the second track (402), wherein the driven member is a roller (105) provided at the head end of the connecting rod (107), and wherein the roller (105) is embedded in the third track (403).
  3. 3. A vacuum butterfly valve according to claim 2, wherein the third track (403) comprises, in succession, a first straight line parallel to the axis of the piston (104), an arc disposed at an angle to the axis of the piston (104), a second straight line parallel to the axis of the piston (104), and a third straight line parallel to the axis of the piston (104), in the path of movement of the valve from fully closed to fully open.
  4. 4. A vacuum butterfly valve according to claim 3, characterized in that at the start of the first straight line segment and at the end of the third straight line segment of the third track (403), the tangential direction of the third track (403) is parallel to the axis of the piston (104) so that the valve is mechanically self-locking in the fully closed and fully open position.
  5. 5. A vacuum butterfly valve according to claim 2, wherein the first track (401) and the second track (402) comprise, in sequence, a first straight line segment guiding the piston (104) to move straight, a spiral line segment guiding the piston (104) to rotate a predetermined angle around its own axis while continuing to move straight, and a second straight line segment guiding the piston (104) to move straight again during the valve opening process.
  6. 6. A vacuum butterfly valve according to claim 5, wherein the spiral segment is a quarter spiral for guiding the piston (104) to rotate 90 °.
  7. 7. The vacuum butterfly valve according to claim 2, further comprising a base (110) and a double-rotation block (109), wherein the base (110) is connected with the cylinder (102) and is provided with a bearing, the double-rotation block (109) is connected with the middle of the connecting rod (107) through a pin and is installed in the bearing, so that the connecting rod (107) can rotate around the bearing and can rotate around the pin, the base (110) is fixed at the tail end of the cylinder (102) through a screw, the bearing is fixedly installed inside the base through a bearing limiting block (111) and the screw, a sealing retainer ring (108) is installed on the connecting rod (107) and is used for realizing dynamic sealing between the connecting rod (107) and the cylinder (102), and the cylinder assembly (1) further comprises a cylinder cover (101) connected with the cylinder (102), and the cylinder cover (101) and the cylinder (102) form a sealed cylinder cavity.
  8. 8. The vacuum butterfly valve according to claim 1, wherein the valve core assembly (2) further comprises a supporting ring (202) sleeved on the valve core (201), the supporting ring (202) is made of high-molecular wear-resistant materials and is used for supporting and guiding the valve core (201) in the valve body (3), the tail end of the connecting rod (107) is fixedly connected with the valve core (201) of the valve core assembly (2) through a screw, the valve core assembly (2) further comprises a sealing ring (203) installed on the circumference of the valve core (201), the sealing ring (203) is used for being attached to a sealing valve seat of the valve body (3) to achieve sealing when the valve is closed, the supporting ring (202) is sleeved on the valve core (201) and is located on the inner side of the sealing ring (203), and the supporting ring (202) is made of PEEK or POM high-molecular wear-resistant materials.
  9. 9. The vacuum butterfly valve according to claim 2, wherein two rollers (105) are respectively arranged on two sides of the head end of the connecting rod (107), the two rollers (105) are embedded into the third rail (403), and the rollers (105) are mounted on the head end of the connecting rod (107) through pin shafts (106).
  10. 10. A control method of a vacuum butterfly valve according to any of claims 1 to 9, wherein the valve opening process of the vacuum butterfly valve comprises the following four stages in sequence: The first stage, the driving piston (104) moves straight along its own axis, namely the third axis (303), the connecting rod (107) and the valve core (201) keep stationary, and the valve is in a closed self-locking state; The second stage, the driving piston (104) continues to do pure linear motion along the third axis (303), in this stage, the connecting rod (107) rotates around the second axis (302), and drives the valve core (201) to translate, so that the sealing ring (203) on the valve core is separated from the valve seat of the valve body (3); A third stage, wherein the driving piston (104) rotates a preset angle around the third axis (303) while linearly moving along the third axis (303), and the connecting rod (107) rotates around the first axis (301) at the stage, so that the valve core (201) is driven to rotate in the valve body (3) to realize the opening of the valve; In the fourth stage, the driving piston (104) moves in a pure straight line along the third axis (303) again until reaching the stroke end, at the moment, the connecting rod (107) and the valve core (201) are kept stationary, and the valve is in an opening self-locking state; The valve closing process of the vacuum butterfly valve is an accurate reverse process of the valve opening process, and comprises the following four stages in sequence: the first stage, the driving piston (104) starts from the valve opening end position and moves downwards along the axis of the driving piston, namely the third axis (303), and the connecting rod (107) and the valve core (201) keep stationary; A second stage in which the drive piston (104) rotates reversely by the predetermined angle about the third axis (303) while continuing to move linearly downward along the third axis (303), and in which the connecting rod (107) rotates reversely about the first axis (301), thereby driving the valve element (201) to rotate reversely by 90 ° in the valve body (3) to effect closing; In the third stage, the driving piston (104) continuously moves downwards along the third axis (303) in a straight line, and in the stage, the connecting rod (107) reversely rotates around the second axis (302) to drive the valve core (201) to translate and enable the sealing ring (203) on the valve core to press the valve seat of the valve body (3); and in the fourth stage, the driving piston (104) continues to move straight downwards to the initial position, and the valve is restored to the closed self-locking state.

Description

Vacuum butterfly valve Technical Field The invention relates to a valve, in particular to a vacuum butterfly valve. Background Vacuum valves are key elements in vacuum systems for changing the direction of air flow, regulating flow, or switching on/off the piping. In the high-precision fields of film coating, mass spectrometry, gas analysis and the like, extremely high requirements are put on a vacuum valve, firstly, the valve is required to act to generate a very small amount of gas particles so as to avoid polluting a vacuum chamber and a process, secondly, the valve is required to have high reliability and can resist pollutants such as dust possibly existing in the process environment, and finally, the valve is required to have a mechanical locking function similar to a gate valve so as to ensure that the state of the valve is not changed when a driving gas source fails accidentally and ensure the safety of a system and the process. The conventional pneumatic butterfly valve widely used at present is generally composed of a pneumatic actuator, a valve rod, a valve body and a valve core, wherein the valve rod is connected with the valve body through a bearing. This structure has inherent drawbacks, failing to meet the requirements of the high-end working conditions described above: The low particle requirement can not be met, the friction between metal and metal can be generated when the bearing between the valve rod and the valve body moves, and metal particles are inevitably generated, so that the vacuum environment is polluted. The reliability is at risk that in environments with multiple dust and multiple process pollutants, the joint of the valve rod and the valve body is easy to be blocked or even dead due to the invasion of the pollutants, so that the valve is invalid. Lacking safety assurance, conventional pneumatic butterfly valves often do not have a mechanical locking function, and the retention of the valve spool is entirely dependent on the continuous source pressure. Once the air source pressure is lost, the valve core can perform unexpected actions under the action of the pipeline pressure difference, and potential safety hazards exist. Disclosure of Invention The invention aims to provide a vacuum butterfly valve, which solves the technical problem that the existing pneumatic butterfly valve cannot simultaneously meet the requirements of high vacuum application scenes on low particle generation, high operation reliability and mechanical self-locking safety in a gas-off state. The invention adopts the following technical scheme that the vacuum butterfly valve comprises a cylinder assembly, a valve core assembly and a valve body, wherein the valve core of the valve core assembly is arranged in the valve body, the cylinder assembly comprises a cylinder barrel, a piston, a connecting rod and a driving conversion mechanism, the piston is movably arranged in the cylinder barrel, a plurality of tracks which are structured into different geometric shapes are arranged on the inner surface and the outer surface of the piston, the driving conversion mechanism comprises a fixing piece fixed on the cylinder barrel and a driven piece connected with the connecting rod, the fixing piece is matched with at least one track on the outer surface of the piston and is used for restraining the piston to generate output motion which is compounded with the linear motion along the axis of the piston and the rotary motion around the axis of the piston under driving, the driven piece is matched with at least one track on the inner surface of the piston and is used for converting the compound output motion of the piston into the motion of the connecting rod, one end of the connecting rod is connected with the driven piece, and the other end of the connecting rod is in driving connection with the valve core so as to drive the valve core to execute the compound motion which is separated from or pressed by a valve seat and rotates. Further, the plurality of tracks on the surface of the piston comprise a first track, a second track and a third track, wherein the first track and the second track are arranged on the outer cylindrical surface of the piston, the third track is arranged on the inner cylindrical surface of the piston, the fixing piece is a special-shaped screw which penetrates through the cylinder barrel and is matched with the first track and the second track, the driven piece is a roller arranged at the head end of the connecting rod, and the roller is embedded into the third track. Further, the third track sequentially comprises a first straight line section parallel to the axis of the piston, an arc section arranged at an included angle with the axis of the piston, a second straight line section parallel to the axis of the piston and a third straight line section parallel to the axis of the piston on a motion path from full closing to full opening of the valve. Further, the first straight line segment start