GM cryocooler and method of operating GM cryocooler

Patent metadata

Field	Value
Publication number	US-11408406-B2
Application number	US-201916427374-A
Country	US
Kind code	B2
Filing date	May 31, 2019
Priority date	Dec 2, 2016
Publication date	Aug 9, 2022
Grant date	Aug 9, 2022

Abstract

A GM cryocooler includes a first cold head including a first displacer that is reciprocable in an axial direction, a first drive piston that drives the first displacer in the axial direction, and a first drive chamber that houses the first drive piston; a second cold head including a second displacer that is reciprocable in the axial direction, and a second cylinder that houses the second displacer; a first intake valve that is connected to both the first drive chamber and the second cylinder so as to supply working gas in parallel to the first drive chamber and the second cylinder; and a first exhaust valve that is connected to both the first drive chamber and the second cylinder so as to collect the working gas in parallel from the first drive chamber and the second cylinder.

First claim

What is claimed is:

1. A GM cryocooler comprising:
a first cold head including:
a first displacer that is reciprocable in an axial direction,
a first cylinder that houses the first displacer,
a first drive piston that drives the first displacer in the axial direction, and
a first drive chamber that houses the first drive piston;

a second cold head including:
a second displacer that is reciprocable in the axial direction,
a second cylinder that houses the second displacer,
a second drive piston that drives the second displacer in the axial direction, and
a second drive chamber that houses the second drive piston;

a first intake valve that is connected to both the first drive chamber and the second cylinder so as to supply a working gas in parallel to the first drive chamber and the second cylinder;
a first exhaust valve that is connected to both the first drive chamber and the second cylinder so as to collect the working gas in parallel from the first drive chamber and the second cylinder;
a second intake valve that is connected to both the second drive chamber and the first cylinder so as to supply the working gas in parallel to the second drive chamber and the first cylinder; and
a second exhaust valve that is connected to both the second drive chamber and the first cylinder so as to collect the working gas in parallel from the second drive chamber and the first cylinder.

2. The GM cryocooler according to claim 1 ,
wherein the first intake valve supplies the working gas to the first drive chamber and the second cylinder during a first intake period,
wherein the first exhaust valve collects the working gas from the first drive chamber and the second cylinder during a first exhaust period,
wherein the second intake valve supplies the working gas to the second drive chamber and the first cylinder during a second intake period, wherein the second intake period overlaps the first exhaust period at least partially, and
wherein the second exhaust valve collects the working gas from the second drive chamber and the first cylinder during a second exhaust period, wherein the second exhaust period overlaps the first intake period at least partially.

3. The GM cryocooler according to claim 2 ,
wherein the second intake period is delayed from the first intake period, and/or
wherein the second exhaust period is delayed from the first exhaust period.

4. The GM cryocooler according to claim 1 , further comprising:
a first branch flow path that includes a first main flow path connected to the second cylinder and a first sub-flow path connected to the first drive chamber, wherein the first branch flow path connects each of the first intake valve and the first exhaust valve to both the first main flow path and first sub-flow path; and
a second branch flow path that includes a second main flow path connected to the first cylinder and a second sub-flow path connected to the second drive chamber, wherein the second branch flow path connects each of the second intake valve and the second exhaust valve to both the second main flow path and the second sub-flow path.

5. The GM cryocooler according to claim 4 ,
wherein the first branch flow path includes a first branch point where the first sub-flow path branches from the first main flow path, and the first sub-flow path includes a first flow path resistance part between the first branch point and the first drive chamber, and/or
wherein the second branch flow path includes a second branch point where the second sub-flow path branches from the second main flow path, and the second sub-flow path includes a second flow path resistance part between the second branch point and the second drive chamber.

6. The GM cryocooler according to claim 4 , further comprising:
a first bypass flow path that connects the second main flow path to the first sub-flow path, the first bypass flow path being configured so as to allow the working gas to flow therethrough when the first cold head is not installed; and
a second bypass flow path that connects the first main flow path to the second sub-flow path, the second bypass flow path being configured so as to allow the working gas to flow therethrough when the second cold head is not installed.

7. The GM cryocooler according to claim 1 ,
wherein the first drive chamber includes a first compartment connected to the first intake valve and the first exhaust valve, and a first gas spring chamber partitioned from the first compartment by the first drive piston, and/or
wherein the second drive chamber includes a second compartment connected to the second intake valve and the second exhaust valve, and a second gas spring chamber partitioned from the second compartment by the second drive piston.

8. The GM cryocooler according to claim 7 , further comprising:
a shunt flow path that allows the first gas spring chamber to communicate with the second gas spring chamber, and the shunt flow path including a flow path resistance part.

9. A GM cryocooler comprising:
a first cold head including a first displacer that is reciprocable in an axial direction, a first drive piston that drives the first displacer in the axial direction, and a first drive chamber that houses the first drive piston;
a second cold head including a second displacer that is reciprocable in the axial direction, and a second cylinder that houses the second displacer;
a first intake valve that is connected to both the first drive chamber and the second cylinder so as to supply a working gas in parallel to the first drive chamber and the second cylinder; and
a first exhaust valve that is connected to both the first drive chamber and the second cylinder so as to collect the working gas in parallel from the first drive chamber and the second cylinder.

Assignees

• Sumitomo Heavy Industries

Inventors

• Xu Mingyao
• Bao Qian
• Morie Takaaki

Classifications

• F04B27/005 Primary

  with two cylinders · CPC title

• F25B9/14

  characterised by the cycle used, e.g. Stirling cycle · CPC title

• F04B37/085

  Regeneration of cryo-pumps · CPC title

• F04B35/008

  the means being a fluid transmission link · CPC title

• F25B2309/002

  with parallel working cold producing expansion devices in one circuit · CPC title