Throttle gate valve

• US 6,293,306 B1
• Filed: 07/10/2000
• Issued: 09/25/2001
• Est. Priority Date: 07/09/1999
• Status: Expired due to Fees

• Current Assignee: Brenes, Arthur
• Original Assignee: Brenes, Arthur
• Inventors: Brenes, Arthur
• Primary Examiner(s): Hepperle, Stephen M.
• Application Number:
  US09/613,175
• Time in Patent Office: 442 Days
• Field of Search: 137/601.09, 137/601.15, 137/601.17, 137/613, 137/614.11, 137/614.12, 137/601.11, 251/279, 251/305
• US Class Current: 137/601.09
• CPC Class Codes: F16K 1/223 with a plurality of valve members
• CPC Class Codes: F16K 27/0218 Butterfly valves
• CPC Class Codes: F16K 27/044 slide valves with flat obturating members
• CPC Class Codes: F16K 3/0281 Guillotine or blade-type valves, e.g. no passage through the valve member
• CPC Class Codes: F16K 51/02 specially adapted for high-vacuum installations
• CPC Class Codes: Y10T 137/87475 Adjacent plate valves always parallel
• CPC Class Codes: Y10T 137/87515 Mechanical movement between actuator and valve
• CPC Class Codes: Y10T 137/87531 Butterfly valve
• CPC Class Codes: Y10T 137/87981 Common actuator

Abstract

A throttle gate valve (10) including an upright, generally rectangular valve housing (12), in which is positioned a linearly movable gate valve (32) for closing off a thru-opening (15) formed in the lower part of housing (12). A pneumatic actuator assembly (14) is provided for moving the gate valve between its opened and closed positions. A throttle vane assembly compartment (16) forms the lower side of valve housing (12) and frames thru-opening (15), and includes a set of throttle vanes (18) rotatably positioned within thru-opening (15), and a drive actuator compartment (20) and motor (21) for controlling the position of throttle vanes (18). A drive actuator (51) is provided for rotating vanes (18) and is sealed by a bellows shield (70) at the point where the drive actuator extends into the interior of the housing.

Claims

1. A throttle gate valve, comprising

a housing defining a thru-opening for controlling vacuum within a process chamber,

a gate valve movable between open and closed positions, in the closed position closing off the thru-opening to prevent the passage of process gases,

a linear conductance throttle vane movably mounted within the thru-opening for throttling flow of gases through the thru-opening when the gate valve is in its open position, and

a drive mechanism for moving the throttle vane in order to vary flow of the process gases, the drive mechanism including a linear drive actuator extending into the housing and including a bellows shield to prevent escape of gases where the linear drive actuator extends into the housing.

2. The throttle gate valve of claim 1 wherein,

the linear conductance throttle valve includes at least one vane that extends across the thru-opening and is rotatably mounted at opposite ends for angular movement between a multiplicity of positions.

3. The throttle gate valve of claim 2 wherein,

the linear conductance throttle valve includes more than one vane, each symmetrically mounted about its axis of rotation.

4. The throttle gate valve of claim 3 wherein,

the linear conductance throttle valve provides a substantially linear response across the thru-opening within a pre-selected operating range.

5. The throttle gate valve of claim 1 wherein,

the housing includes first and second side chambers, one on each side of the throttle vane, and each side chamber being defined at least partially by an interior wall that provides a rotatable support for the throttle vane, the linear drive actuator extending into the first side chamber and connecting to the throttle vane for rotation of the vane, the housing further including a port providing fluid communication between the first side chamber and the thru-opening,

so that when the thru-opening is at vacuum, so too is the first side chamber.

6. The throttle gate valve of claim 5 wherein,

the housing further includes a gate valve chamber for positioning the gate valve in its closed position, and

the port provides fluid communication between the first side chamber and the thru-opening via the gate valve chamber.

7. The throttle gate valve of claim 5 wherein,

the port is formed to prevent fluid communication between the first side chamber and the process chamber when the gate valve is closed.

8. The throttle gate valve of claim 5 wherein,

the housing includes a second port for providing fluid communication between the second side chamber and the thru-opening.

9. The throttle gate valve of claim 8 wherein,

the housing further includes a gate valve chamber for positioning the gate valve in its closed position, and

the port provides fluid communication between the second side chamber and the thru-opening via the gate valve chamber.

10. The throttle gate valve of claim 1 wherein,

the linear drive actuator includes a drive rod mounted for linear movement, including an inner end extending into the housing of the throttle gate valve for driving connection to the throttle valve and an outer end exterior of the housing, the bellows shield connected at one end to the outer end of the drive rod and at another end to the housing.

11. The throttle gate valve of claim 10 wherein,

the housing includes a seal around the drive rod so that the inner end of the drive rod can be exposed to vacuum pressures while the outer end of the drive rod is exposed to atmosphere.

12. The throttle gate valve of claim 11 wherein,

the linear drive actuator includes a drive motor, a tubular, interiorly threaded drive shaft drivingly mounted to the drive motor, and an exteriorly threaded screw threadably secured within the threaded drive shaft for linear movement in response to rotation of the drive shaft.

13. The throttle gate valve of claim 10 wherein,

the housing includes an interior chamber that houses the linear drive actuator and its connection to the throttle vane, and the housing further includes a first port leading from the interior chamber to the thru-opening, for providing fluid communication there between.

14. The throttle gate valve of claim 13 wherein,

the throttle vane is rotatably mounted to shafts at opposite sides of the throttle valve, one of the shafts extending into the interior chamber, the housing including a second side chamber from which the other of the shafts is accessible, and the housing further including a second port leading from the second side chamber to the thru-opening, for providing fluid communication there between.

15. The throttle gate valve of claim 14 wherein,

the housing includes a gate valve chamber for positioning the gate valve in its open position, the housing further including a purge port for introducing a gas into the gate valve chamber, the first and second ports providing fluid communication via the gate valve chamber, whereby the gas introduced into the gate valve chamber can migrate to the interior chamber and the second side chamber.

16. The throttle gate valve of claim 15 wherein,

the gate valve includes a shield at the lower end of the gate valve, the shield adapted to minimize flow of gases into the gate valve chamber when the gate valve is in its open position, the first and second ports being positioned on the gate valve chamber side of the shield.

17. A throttle vane assembly for controlling vacuum to a process chamber, comprising:

a housing defining a thru-opening,

a throttle vane rotatably mounted in the thru-opening for controlling vacuum pressure to the process chamber,

the housing including a first side chamber defined at least partially by an interior wall that rotatably supports the throttle vane,

a drive mechanism for rotating the throttle vane, the drive mechanism extending into the side chamber from exterior of the housing and drivingly connecting to the throttle vane for rotation thereof,

the housing further including a port for providing fluid communication between the thru-opening and the side chamber,

whereby a pressure differential can be avoided between the thru-opening and the side chamber.

18. The throttle vane assembly of claim 17 wherein,

the housing includes first and second side chambers, one on each side of the throttle vane, and each side chamber being defined at least partially by an interior wall that provides a rotatable support for the throttle vane, the linear drive actuator extending into the first side chamber and connecting to the throttle vane for rotation of the vane, the housing further including a port providing fluid communication between the first side chamber and the thru-opening,

so that when the thru-opening is at vacuum, so too is the first side chamber.

19. The throttle gate valve of claim 18 wherein,

the housing further includes a gate valve chamber for positioning the gate valve in its closed position, and

the port provides fluid communication between the first side chamber and the thru-opening via the gate valve chamber.

20. The throttle gate valve of claim 18 wherein,

the port is formed to prevent fluid communication between the first side chamber and the process chamber when the gate valve is closed.

21. The throttle gate valve of claim 18 wherein,

the housing includes a second port for providing fluid communication between the second side chamber and the thru-opening.

22. The throttle gate valve of claim 21 wherein,

the housing further includes a gate valve chamber for positioning the gate valve in its closed position, and

the port provides fluid communication between the second side chamber and the thru-opening via the gate valve chamber.