Rotary shear valve with a two-pin drive shaft for liquid chromatography applications

Patent metadata

Field	Value
Publication number	US-10364902-B2
Application number	US-201214117397-A
Country	US
Kind code	B2
Filing date	Jun 11, 2012
Priority date	Jun 17, 2011
Publication date	Jul 30, 2019
Grant date	Jul 30, 2019

Abstract

A rotary shear valve assembly for liquid chromatography applications comprises a rotor assembly having a rotor and a drive shaft with a head portion. The rotor has a substantially planar surface with one or more rotor grooves and a pair of holes. The head portion has two pins. The pins are disposed substantially diametrically opposite of each other on a line through a center of the head portion. Each pin mates with one of the holes in the rotor. The rotor assembly can further comprise means for urging the rotor surface against the stator surface such that each rotor groove aligns with and provides a fluidic channel between two of the stator openings.

First claim

What is claimed is:

1. A rotary shear valve assembly, comprising:
a rotor assembly having a rotor and a drive shaft, the rotor having a substantially planar surface and the drive shaft having a head portion, the substantially planar surface having one or more rotor grooves, a first hole having a circular cross-section and a second hole opposite to the first hole along a diameter on the substantially planar surface defined between the first and second holes, the second hole having an elliptical cross-section which is not circular and wherein at least one of the rotor grooves intersects the diameter, the head portion having a first pin and a second pin, the first and second pins being disposed substantially diametrically opposite of each other on a line through a center of the head portion, the first pin having a diameter that is less than a diameter of the second pin, the first pin being mated with the first hole in the rotor and the second pin being mated with the second hole in the rotor, wherein the first hole in the rotor is sized to receive closely the first pin.

2. The rotary shear valve assembly of claim 1 , further comprising:
a housing for the rotor assembly, one end of the drive shaft extending through an opening at a base of the housing; and
a clamp secured to the end of the drive shaft extending through the opening at the base of the housing.

3. The rotary shear valve assembly of claim 1 wherein the elliptical cross-section has a minor axis and wherein a dimension of the second hole along the minor axis is sized to closely receive the diameter of the second pin.

4. The rotary shear valve assembly of claim 1 , further comprising a stator with a plurality of ports and a substantially planar surface with openings to the ports; and wherein the rotor assembly further comprises means for urging the rotor surface against the stator surface such that each rotor groove aligns with and provides a channel between two of the ports of the stator.

5. The rotary shear valve assembly of claim 4 , wherein the means for urging includes a plurality of clover springs around the drive shaft, the clover springs being compressed to produce an axial force.

6. The rotary shear valve assembly of claim 4 , wherein a seal formed between the surfaces of the rotor and the stator substantially prevents fluidic leakage up to 20,000 psi.

7. A rotary shear valve assembly, comprising:
a rotor assembly having a drive shaft and a rotor, the drive shaft having a head portion with only a first pin and a second pin each extending orthogonally from a distal surface of the head portion, the first pin having a smaller diameter than a diameter of the second pin, the rotor having a substantially planar surface, the substantially planar surface having one or more rotor grooves, a first hole having a circular cross-section and tightly receiving the first pin, and a second hole opposite to the first hole on a diameter on the substantially planar surface defined between the first and second holes, the second hole having an elliptical cross-section which is not circular and receiving the second pin, wherein at least one of the rotor grooves intersects the diameter.

8. The rotary shear valve assembly of claim 7 , wherein the pins are disposed substantially diametrically opposite of each other on a line through a center of the head portion.

9. The rotary shear valve assembly of claim 7 , further comprising:
a housing for the rotor assembly, one end of the drive shaft extending through an opening at a base of the housing; and
a clamp secured to the end of the drive shaft extending through the opening at the base of the housing.

10. The rotary shear valve assembly of claim 7 , further comprising a stator with a plurality of ports and a substantially planar surface with openings to the ports; and wherein the rotor assembly further comprises means for urging the rotor surface against the stator surface such that each rotor groove aligns with and provides a fluidic channel between two of the stator openings.

11. The rotary shear valve assembly of claim 7 wherein the elliptical cross-section has a minor axis and wherein a dimension of the second hole along the minor axis is sized to closely receive the diameter of the second pin.

12. The rotary shear valve assembly of claim 10 , wherein the means for urging includes a plurality of clover springs around the drive shaft and compressed to provide an axial force.

13. The rotary shear valve assembly of claim 12 , wherein a seal formed between the surfaces of the rotor and the stator substantially prevents fluidic leakage up to 20,000 psi.

Assignees

• Moeller Mark W
• Jencks Robert A
• Waters Technologies Corp

Inventors

• Moeller Mark W
• Jencks Robert A

Classifications

• F16K5/00 Primary

  {Plug valves;} Taps or cocks comprising only cut-off apparatus having at least one of the sealing faces shaped as a more or less complete surface of a solid of revolution, the opening and closing movement being predominantly rotary (taps of the lift-valve type F16K1/00) · CPC title

• F16K11/0743 Primary

  with both the supply and the discharge passages being on one side of the closure plates · CPC title

• G01N2030/202

  rotary valves · CPC title