Abstract: Thermal energy transmission from a cryocooler cold finger is enhanced by means of a high thermal conductivity material used for or placed adjacent the cold finger end cap. In addition, the actual or effective surface area contacted by the working gas proximate the endcap is increased, thereby increasing the convective heat transfer coefficient. These features permit the coolest gas expansion space in the cold finger to be provided within the highly thermally conductive end cap, unlike many conventional designs in which the cold finger of low thermally conductive metal forms the expansion space side walls and the endcap forms only the axially facing outer surface in contact with the cooled equipment. Having the expansion space built into the high thermally conductive end cap reduces the temperature drop between the load to be cooled and the gas (e.g., helium), thus increasing the thermodynamic cycle efficiency.

Abstract: A cryocooler is provided that includes: a regenerator piston; a drive coupler; and a link flexure having a proximal end coupled by a first pin to the drive coupler and having a distal end coupled by a second pin to the regenerator piston, where the link flexure forms a vane having flattened opposing faces that are orthogonal to a longitudinal axis for the first and second pin.

Abstract: A cryocooler is provided that includes: a regenerator piston; a drive coupler; and a link flexure having a proximal end coupled by a first pin to the drive coupler and having a distal end coupled by a second pin to the regenerator piston, where the link flexure forms a vane having flattened opposing faces that are orthogonal to a longitudinal axis for the first and second pin.

Abstract: A cryocooler is provided that includes: a regenerator piston; a drive coupler; and a link flexure having a proximal end coupled by a first pin to the drive coupler and having a distal end coupled by a second pin to the regenerator piston, where the link flexure forms a vane having flattened opposing faces that are orthogonal to a longitudinal axis for the first and second pin.

Abstract: The size of a miniature cryocooler operating on the Stirling refrigeration cycle is further reduced by shortening a first thermal regenerator module (R) disposed on a cold side of a thermal barrier (T) and providing a second thermal regenerator module (R1) disposed on a warm side of the thermal barrier (T). A thermally insulated fluid flow passage is disposed to interconnect the first and second regenerator modules to thermally insulate the fluid passage. In combination, the first and second regenerator modules provide 100% thermal regenerator effectiveness in the device.

Abstract: The size of a miniature cryocooler (100) operating on the Stirling refrigeration cycle is further reduced by shortening a first thermal regenerator module (R) disposed on a cold side of a thermal barrier (T) and providing a second thermal regenerator module (R1) disposed on a warm side of the thermal barrier (T). A thermally insulated fluid flow passage (172) is disposed to interconnect the first and second regenerator modules to thermally insulate the fluid passage (172). In combination, the first and second regenerator modules provide 100% thermal regenerator effectiveness in the device.

Abstract: The invention is directed to an improved cryogenic cooler with an expander where the regenerator matrix is decoupled from the displacer or piston, thereby allowing the design of each to be optimized substantially independently. The regenerator matrix is preferably positioned spaced apart from the displacer and can be designed to enhance thermal exchanges and flow rates of the working gas. In one embodiment, the regenerator matrix has a serpentine shape or U-shape disposed around the displacer and the cold finger. Preferably, the regenerator matrix is static. The thermal lengths of the cold finger and/or the displacer can be extended by minimizing their geometrical lengths. Additionally, the structural integrity or stiffness of the cold finger and/or displacer can be strengthened.

Abstract: Provided for an embodiment is a support member for a cryogenic cooler's expander. The support member provides stiffness to the expander to reduce movements at the expander's distal end and may increase the natural frequency of the expander. The support member may increase the natural frequency of the expander at least about two times in the bending and/or twisting sense. The bending natural frequency of the expander and support sub-assembly may be at least about two times greater or lower than the natural frequency of the electrical wires that connect an infrared sensor to a control processing unit to reduce the maximum stress applied to the electrical wires during use. In another embodiment, additional or redundant electrical pathways are provided for connections between the infrared sensor and the CPU. Furthermore, shock absorber and/or shock diverters are provided on rigid pins that connect the electrical wires to the CPU.

Abstract: In one embodiment, as cryocooler is provided that includes: a regenerator piston; a drive coupler; and a link flexure having a proximal end coupled by a first pin to the drive coupler and having a distal end coupled by a second pin to the regenerator piston, wherein the link flexure forms a vane having flattened opposing faces that are orthogonal to a longitudinal axis for the first and second pin.

Abstract: The present invention relates to a cryogenic cooler's expander supported by a support member, preferably a truncated conical tube. The support member provides additional stiffness to the expander to reduce movements at the distal end of the expander. The support member also increases the natural frequency of the expander. In one embodiment, the support member increases the natural frequency of the expander at least about two (2) times in the bending and/or twisting sense. In another embodiment, the bending natural frequency of the expander and support sub-assembly is at least about two times greater or lower than the natural frequency of the electrical wires that connect the infrared sensor to a control processing unit to reduce the maximum stress applied to the electrical wires during use. In another embodiment, additional or redundant electrical pathways are provided for the connection between the infrared sensor and the CPU.

Abstract: The invention is directed to an improved cryogenic cooler with an expander where the regenerator matrix is decoupled from the displacer or piston, thereby allowing the design of each to be optimized substantially independently. The regenerator matrix is preferably positioned spaced apart from the displacer and can be designed to enhance thermal exchanges and flow rates of the working gas. In one embodiment, the regenerator matrix has a serpentine shape or U-shape disposed around the displacer and the cold finger. Preferably, the regenerator matrix is static. The thermal lengths of the cold finger and/or the displacer can be extended by minimizing their geometrical lengths. Additionally, the structural integrity or stiffness of the cold finger and/or displacer can be strengthened.

Abstract: A compact cryocooler includes a gas compression piston (304) supported for reciprocal linear translation along a first longitudinal axis (308) and a gas displacing piston (362) supported for reciprocal linear translation along a second longitudinal axis (366). The first longitudinal axis (308) and second longitudinal axis (366) are substantially orthogonal. A rotary motor (302) rotates a rotor (324) and associated motor shaft (320) about a motor rotation axis (328) disposed substantially parallel with the second longitudinal axis (366). Motor shaft (320) first and second mounting features (336, 340) traverse first and second eccentric paths around the motor rotation axis. A first drive coupling couples the first mounting feature (336) with the gas compression piston (304) and delivers a reciprocal linear translation along the first longitudinal axis (308) thereto.

Abstract: A miniature cooling device includes numerous improvements capable of increasing the reliability and useful lifetime of the device, as well as improving electrical power to cooling power conversion efficiency. The improvements include a DC motor shaft design that incorporates a flywheel mass 314 with a solid shaft cross-section 300 for increasing shaft stiffness and magnetic flux density in the DC motor. Additional improvements include a bend resistant flexible vane 1114 in the DC motor to compression piston drive coupler, and a sealed cover set configured to be removable to make a motor repair and then replaced.

Abstract: An integrated sensor assembly (10) includes a gas compression unit (104) having a first longitudinal axis (308) and a gas expansion unit (112) having a second longitudinal axis (366) and the gas expansion unit is disposed with its second longitudinal axis orthogonal to the gas compression unit first longitudinal axis (308). A rotary motor (302) includes a rotor (324) supported for rotation with respect to a motor rotation axis (328) and the sensor assembly configuration is folded to orient the motor rotation axis substantially parallel with the second longitudinal axis (366). A motor shaft (320) extending from the rotor includes a first and second mounting features (336, 340) disposed substantially parallel with and radially offset from the motor rotation axis (328). A first drive coupling couples between the first mounting feature (336) and a gas compression piston (304) and drives the piston (304) with a reciprocal linear translation directed along the first longitudinal axis (308).

Abstract: A refrigeration device includes a gas displacing piston (362) movable within a gas expander cylinder (364). The volume of a gas expansion space (362) is varied as the gas displacing piston (362) is moved over an expansion stroke range. The device includes a compression spring (622) disposed to bias the gas displacing piston (362) toward a compression stroke top end position (85). A cable element (606) extends into the gas expansion cylinder (364) and attaches to the gas displacing piston (362). A motive drive device (302) applies a tensioning force to the cable (606) and the tension force opposes the spring biasing force and moves the gas displacing piston (362) to a compression stroke bottom end position (83).

Abstract: A regenerator matrix 215 disposed in a fluid conduit 152 for exchanging thermal energy with a fluid passing through the fluid conduit. The regenerator matrix 215 has a variable fluid flow resistance and a variable capacity for convective heat transfer with the fluid along it longitudinal length. Preferably, the flow resistance and the capacity for convective heat transfer between the fluid and the regenerator matrix each increase as the fluid flows from a hot end to a cold end of the fluid conduit 152. The regenerator matrix 215 is formed from individual screen elements 50 or from stacks of screen elements sintered together as composite regenerator elements 110. A first portion 235 of the regenerator matrix made from first individual screen elements is disposed at the hot end of the regulator matrix 215. A second portion 210 of the regenerator matrix made from second individual screen elements is disposed at the cold end of the regulator matrix.

Abstract: A miniature cooling device includes numerous improvements capable of increasing the reliability and useful lifetime of the device, as well as improving electrical power to cooling power conversion efficiency. The improvements include a unitary DC motor shaft design that incorporates a unitary mass flywheel into the shaft element and provides a solid shaft cross-section for increasing magnetic flux density in the DC motor. Additional improvements include a bend resistant flexible vane in the DC motor to compression piston drive coupler, reduced dead space volume within the compression cylinder, improved heat dissipation by a cylinder head cover and an athermalized compressor design that provides uniformly efficient operation over a wide range of operating temperatures. Further improvements include fabrication and coating improvements that increase the life of compression piston and compression cylinder wear surfaces.

Abstract: A miniature cooling device includes numerous improvements capable of increasing the reliability and useful lifetime of the device, as well as improving electrical power to cooling power conversion efficiency. The improvements include a unitary DC motor shaft design that incorporates a unitary mass flywheel into the shaft element and provides a solid shaft cross-section for increasing magnetic flux density in the DC motor. Additional improvements include a bend resistant flexible vane in the DC motor to compression piston drive coupler, reduced dead space volume within the compression cylinder, improved heat dissipation by a cylinder head cover and an athermalized compressor design that provides uniformly efficient operation over a wide range of operating temperatures. Further improvements include fabrication and coating improvements that increase the life of compression piston and compression cylinder wear surfaces.

Abstract: An integrated sensor assembly (10) includes a gas compression unit (104) having a first longitudinal axis (308) and a gas expansion unit (112) having a second longitudinal axis (366) and the gas expansion unit is disposed with its second longitudinal axis orthogonal to the gas compression unit first longitudinal axis (308). A rotary motor (302) includes a rotor (324) supported for rotation with respect to a motor rotation axis (328) and the sensor assembly configuration is folded to orient the motor rotation axis substantially parallel with the second longitudinal axis (366). A motor shaft (320) extending from the rotor includes a first and second mounting features (336, 340) disposed substantially parallel with and radially offset from the motor rotation axis (328). A first drive coupling couples between the first mounting feature (336) and a gas compression piston (304) and drives the piston (304) with a reciprocal linear translation directed along the first longitudinal axis (308).

Abstract: A refrigeration device includes a gas displacing piston (362) movable within a gas expander cylinder (364). The volume of a gas expansion space (362) is varied as the gas displacing piston (362) is moved over an expansion stroke range. The device includes a compression spring (622) disposed to bias the gas displacing piston (362) toward a compression stroke top end position (85). A cable element (606) extends into the gas expansion cylinder (364) and attaches to the gas displacing piston (362). A motive drive device (302) applies a tensioning force to the cable (606) and the tension force opposes the spring biasing force and moves the gas displacing piston (362) to a compression stroke bottom end position (83).