Compact gate valve

• US 4,062,515 A
• Filed: 05/13/1976
• Issued: 12/13/1977
• Est. Priority Date: 05/13/1976
• Status: Expired due to Term

• Current Assignee: The United States of America as represented by the United States Energy Research and Development Administration
• Original Assignee: The United States of America as represented by the United States Energy Research and Development Administration
• Inventors: Bobo, Gerald E.
• Primary Examiner(s): Nilson, Robert G.
• Application Number:
  US05/686,446
• Time in Patent Office: 579 Days
• Field of Search: 251/58, 251/167, 251/169, 251/175, 251/187, 251/195-202, 251/335 B
• US Class Current: 251/167
• CPC Class Codes: F16K 3/10 with special arrangements for separating the sealing faces or for pressing them together

Abstract

This invention relates to a double-disc gate valve which is compact, comparatively simple to construct, and capable of maintaining high closing pressures on the valve discs with low frictional forces. The valve casing includes axially aligned ports. Mounted in the casing is a sealed chamber which is pivotable transversely of the axis of the ports. The chamber contains the levers for moving the valve discs axially, and an actuator for the levers. When an external drive means pivots the chamber to a position where the discs are between the ports and axially aligned therewith, the actuator for the levers is energized to move the discs into sealing engagement with the ports.

Claims

1. A gate valve comprising:

a casing enclosing annular seating surfaces defining first and second ports having a common axis;

a gate assembly mounted in said casing for arcuate movement toward and away from said common axis and including;

a. a pair of valve discs having frontal sealing surfaces for respectively engaging said seating surfaces to close said ports;

b. levers respectively connected to said discs;

c. means for operating said levers to move said discs along said axis to open and close said ports; and

d. a housing isolating said levers and said means from said casing, said housing including flexible sealing means respectively connected to said discs for accommodating movement of said discs along said axis.

2. The valve of claim 1 wherein said levers are generally L-shaped arms which are pivotally connected to one another intermediate of their ends.

3. The valve of claim 2 wherein the shorter legs of said levers are respectively connected to the backs of said valve discs.

4. The valve of claim 1 wherein said flexible sealing means are bellows.

5. The valve of claim 1 wherein said housing is provided with a pair of axially aligned support shafts which in turn are supported by said casing.

6. The valve of claim 1 wherein said housing carries stops for limiting axial movement of said discs.

7. The valve of claim 1 wherein said gate assembly includes guide means for promoting straight-line axial movement of said discs.

8. A gate valve comprising:

a casing enclosing annular seating surfaces defining opposed valve ports having a common centerline;

a gate assembly pivotally mounted in said casing for movement toward and away from said centerline, said assembly including;

a. a pair of valve discs having frontal sealing surfaces for respectively engaging said seating surfaces to close said ports;

b. at least two generally L-shaped levers coupled at an intermediate point for pivotal movement about a common axis, the shorter legs of said levers being pivotally connected to different valve discs;

c. drive means for effecting relative movement of said levers about said axis to move said discs along said centerline to close and open said ports;

d. a housing encompassing said levers and drive means for isolating said levers and drive means from said casing, said housing including bellows respectively connected to said discs for accommodating movement of said discs along said centerline; and

e. a rotatable shaft in said casing affixed to said housing for pivoting said gate assembly.

9. The valve of claim 8 wherein said shaft is hollow.

10. A gate valve comprising:

a casing enclosing annular seating surfaces defining first and second ports having a common axis;

a gate assembly in said casing including;

a. a pair of valve discs having frontal sealing surfaces for respectively engaging said seating surfaces to close said ports;

b. levers respectively connected to said discs;

c. means for operating said levers to move said discs along said axis to open and close said ports; and

d. a housing isolating said levers and said means from said casing, said housing including flexible sealing means respectively connected to said discs for accommodating movement of said discs along said axis, said housing being provided with a pair of axially aligned support shafts which in turn are supported by said casing, one of said shafts being hollow and being coupled to shaft-rotation means outside said casing.