Abstract: There is provided a starting method for a cryocooler, the cryocooler including a compressor, a cold head, a high pressure line, and a low pressure line, the method including increasing a volume of the high pressure line when the cold head is at a room temperature, cooling the cold head from the room temperature to a cryogenic temperature while controlling an operation frequency of the compressor based on a pressure of the high pressure line or a differential pressure between the high pressure line and the low pressure line, after the volume of the high pressure line has been increased, decreasing the volume of the high pressure line after the cold head has been cooled to the cryogenic temperature, and maintaining the cold head at the cryogenic temperature after the volume of the high pressure line has been decreased.

Abstract: A cryocooler includes: a compressor; a plurality of cold heads connected in parallel to the compressor; a pressure sensor that measures a pressure of a working gas on a supply side from the compressor to the plurality of cold heads or on a collection side from the plurality of cold heads to the compressor; and a controller configured to acquire, for each of the plurality of cold heads, individual pressure waveform data measured by the pressure sensor when the cold head is individually operated, and to operate the plurality of cold heads simultaneously and asynchronously based on the individual pressure waveform data of the plurality of cold heads.

Abstract: A cryocooler includes an expander that includes a cooling stage, an exhaust temperature sensor that measures an exhaust temperature which is a temperature of a working gas exhausted from the expander and outputs an exhaust temperature signal indicating the measured exhaust temperature, and a controller that compares, during execution of initial cooling in which the cooling stage is cooled from an initial temperature to a cryogenic temperature, the measured exhaust temperature to a reference temperature based on the exhaust temperature signal and completes the initial cooling in a case where a temperature difference between the measured exhaust temperature and the reference temperature is within a reference range.

Abstract: A cryocooler includes a cold head, a plurality of compressor main bodies that are connected to the cold head in parallel, a plurality of state detection sensors that are provided to correspond to the plurality of compressor main bodies respectively and each detect a state of a corresponding compressor main body to output a state detection signal, and a compressor control unit that is configured to, in a case where the state detection signal from any one state detection sensor of the plurality of state detection sensors indicates that the corresponding compressor main body is stopped, stop also the other compressor main bodies.

Abstract: A cryocooler includes a compressor, an expander, a gas line that allows a working gas to be circulated between the compressor and the expander and includes a high pressure line through which the working gas is supplied from the compressor to the expander and a low pressure line through which the working gas is collected from the expander to the compressor, a bypass line that connects the high pressure line to the low pressure line such that the working gas bypasses the expander and returns from the high pressure line to the low pressure line, and a bypass flow rate control unit that controls a flow rate of the working gas flowing in the bypass line to provide pressure control of the gas line. The bypass line includes a variable flow rate bypass and a fixed flow rate bypass.

Abstract: A cryocooler includes an expander that includes a cooling stage, an exhaust temperature sensor that measures an exhaust temperature which is a temperature of a working gas exhausted from the expander and outputs an exhaust temperature signal indicating the measured exhaust temperature, and a controller that compares, during execution of initial cooling in which the cooling stage is cooled from an initial temperature to a cryogenic temperature, the measured exhaust temperature to a reference temperature based on the exhaust temperature signal and completes the initial cooling in a case where a temperature difference between the measured exhaust temperature and the reference temperature is within a reference range.

Abstract: There is provided a starting method for a cryocooler, the cryocooler including a compressor, a cold head, a high pressure line, and a low pressure line, the method including increasing a volume of the high pressure line when the cold head is at a room temperature, cooling the cold head from the room temperature to a cryogenic temperature while controlling an operation frequency of the compressor based on a pressure of the high pressure line or a differential pressure between the high pressure line and the low pressure line, after the volume of the high pressure line has been increased, decreasing the volume of the high pressure line after the cold head has been cooled to the cryogenic temperature, and maintaining the cold head at the cryogenic temperature after the volume of the high pressure line has been decreased.

Abstract: A cryocooler includes a cold head, a plurality of compressor main bodies that are connected to the cold head in parallel, a plurality of state detection sensors that are provided to correspond to the plurality of compressor main bodies respectively and each detect a state of a corresponding compressor main body to output a state detection signal, and a compressor control unit that is configured to, in a case where the state detection signal from any one state detection sensor of the plurality of state detection sensors indicates that the corresponding compressor main body is stopped, stop also the other compressor main bodies.

Abstract: A cryocooler includes a compressor, an expander, a gas line that allows a working gas to be circulated between the compressor and the expander and includes a high pressure line through which the working gas is supplied from the compressor to the expander and a low pressure line through which the working gas is collected from the expander to the compressor, a bypass line that connects the high pressure line to the low pressure line such that the working gas bypasses the expander and returns from the high pressure line to the low pressure line, and a bypass flow rate control unit that controls a flow rate of the working gas flowing in the bypass line to provide pressure control of the gas line. The bypass line includes a variable flow rate bypass and a fixed flow rate bypass.

Abstract: A network transaction system applicable to cyberspace banking services using an open network, which allows customers to authenticate themselves through a simplified procedure. A customer's terminal station and a plurality of bank systems are interconnected via networks, and it is assumed that the customer wishes to newly open a bank account in a bank system among them, or a target bank system, and that the customer has an existing bank account in a different bank system, or an cooperative bank system. Using his/her terminal station, the customer applies for a new bank account by supplying the target bank system with a ciphertext message containing existing account information descriptive of the customer's bank account in the cooperative bank system. The target bank system requests the cooperative bank system to confirm the customer's existing bank account, while forwarding thereto a part of the ciphertext message containing the existing account information.

Abstract: A network transaction system applicable to cyberspace banking services using an open network, which allows customers to authenticate themselves through a simplified procedure. A customer's terminal station and a plurality of bank systems are interconnected via networks, and it is assumed that the customer wishes to newly open a bank account in a bank system among them, or a target bank system, and that the customer has an existing bank account in a different bank system, or an cooperative bank system. Using his/her terminal station, the customer applies for a new bank account by supplying the target bank system with a ciphertext message containing existing account information descriptive of the customer's bank account in the cooperative bank system. The target bank system requests the cooperative bank system to confirm the customer's existing bank account, while forwarding thereto a part of the ciphertext message containing the existing account information.