Asymmetric gas bearing bushing for thermo-pump

A thermo-pump comprising:

• a sealed casing, wherein the sealed casing is divided into a main casing volume and one or more secondary volumes;
• a shaft, wherein the shaft is configured to be driven to cause the shaft to linearly oscillate within the sealed casing;
• a displacer, wherein the displacer is coupled to the shaft and oscillates within the main casing volume based on oscillation of the shaft, wherein oscillation of the displacer creates a pressure gain between a high-pressure phase and a low-pressure phase;
• one or more sealing rings, wherein the one or more sealing rings are coupled to the displacer and extend radially outward into the main casing volume, wherein the one or more sealing rings are made from a sealing ring material selected to have at least one of a sealing ring thermal conductivity coefficient or a sealing ring thermal expansion coefficient below a threshold;
• an insert, wherein the insert is configured to form a perimeter of the main casing volume, wherein the insert is made from an insert material selected to have at least one of an insert thermal conductivity coefficient or an insert thermal expansion coefficient below the threshold, wherein the one or more sealing rings and the insert direct a gas through the displacer;
• one or more bushings, wherein the one or more bushing separate the sealed casing into the main casing volume and the one or more secondary volumes;
• and
• one or more gas bearings configured to prevent contact between the shaft and the sealed casing, wherein the one or more gas bearings are configured to operate based on the high-pressure phase and the low-pressure phase created by pressure oscillations caused by the oscillation of the displacer, wherein the one or more gas bearings comprises:
• a cylinder with an inner cylinder radius;
• wherein the inner cylinder radius is larger than a radius of the shaft;
• a gas bearing radius, wherein the gas bearing radius is greater than the shaft radius and less than the inner cylinder radius;
• wherein a gap exists between the cylinder and the shaft, wherein the gap contains a pressurized gas, the pressurized gas configured to prevent contact between the cylinder and the shaft;
• and
• a preloaded gas bearing interface to form an asymmetric gap between the cylinder and the shaft, wherein the preloaded gas bearing interface is positioned to control a size of the gap,
• wherein the preloaded gas bearing interface is positioned at a predetermined location along a section of the shaft where the gap is smallest.

A system, comprising:

• a broadband plasma light source;
• and
• a thermo-pump the thermo-pump configured to provide pressurized gas to the broadband plasma light source, comprising:
• a sealed casing, wherein the sealed casing is divided into a main casing volume and one or more secondary volumes;
• a shaft, wherein the shaft is configured to be driven to cause the shaft to linearly oscillate within the sealed casing;
• a displacer, wherein the displacer is coupled to the shaft and oscillates within the main casing volume based on oscillation of the shaft, wherein oscillation of the displacer creates a pressure gain between a high-pressure phase and a low-pressure phase;
• one or more sealing rings, wherein the one or more sealing rings are coupled to the displacer and extend radially outward into the main casing volume, wherein the one or more sealing rings are made from a sealing ring material selected to have at least one of a sealing ring thermal conductivity coefficient or a sealing ring thermal expansion coefficient below a threshold;
• an insert, wherein the insert is configured to form a perimeter of the main casing volume, wherein the insert is made from an insert material selected to have at least one of an insert thermal conductivity coefficient or an insert thermal expansion coefficient below the threshold, wherein the one or more sealing rings and the insert direct a gas through the displacer;
• one or more bushings, wherein the one or more bushing separate the sealed casing into the main casing volume and the one or more secondary volumes;
• and
• one or more gas bearings configured to prevent contact between the shaft and the sealed casing, wherein the one or more gas bearings are configured to operate based on the high-pressure phase and the low-pressure phase created by pressure oscillations caused by the oscillation of the displacer, wherein at least one of the one or more gas bearings comprises:
• a cylinder with an inner cylinder radius;
• wherein the inner cylinder radius is larger than the shaft radius, wherein the shaft is located within the cylinder;
• a gas bearing radius, wherein the gas bearing radius is greater than the shaft radius and less than the inner cylinder radius;
• wherein a gap exists between the cylinder and the shaft, wherein the gap contains a pressurized gas, the pressurized gas configured to prevent contact between the cylinder and the shaft;
• and
• a preloaded gas bearing interface to form an asymmetric gap between the cylinder and the shaft, wherein the preloaded gas bearing interface is positioned to control a size of the gap,
• wherein the preloaded gas bearing interface is positioned at a predetermined location along a section of the shaft where the gap is smallest.

A method for manufacturing a gas bearing comprising:

• making a piston with a piston radius and a cylinder with an inner cylinder radius, wherein the piston radius and the inner cylinder radius are equal;
• positioning the piston within the cylinder, wherein the piston and cylinder are positioned such that there is a gap between the piston and the cylinder;
• supplying a pressurized gas to the gap, wherein the pressurized gas is configured to prevent contact between the cylinder and the piston;
• wherein a preloaded gas bearing interface is at a location to form an asymmetric gap between the cylinder and the piston, wherein the preloaded gas bearing interface is positioned at a pre-determined location along a section of the piston where the gap is smallest;
• and
• preloading the gas bearing.