摘要:
A rotary disc valve unit and refrigerators containing a rotary disc valve unit that has multiple valves, in which at least one rotary valve has ports connecting to the regenerator and at least one rotary valve has ports connecting to the warm ends of one or more pulse tubes where the rotary valve with ports for the regenerator has lighter contact than the rotary valve with ports for the pulse tubes. The valve face is divided into an inner area with ports for the pulse tubes and an outer area with ports for the regenerator, the inner area having a greater sealing pressure than the outer area.
摘要:
A rotary disc valve unit and refrigerators containing a rotary disc valve unit that has multiple valves, in which at least one rotary valve has ports connecting to the regenerator and at least one rotary valve has ports connecting to the warm ends of one or more pulse tubes where the rotary valve with ports for the regenerator has lighter contact than the rotary valve with ports for the pulse tubes. The valve face is divided into an inner area with ports for the pulse tubes and an outer area with ports for the regenerator, the inner area having a greater sealing pressure than the outer area.
摘要:
A pulse tube system for generating refrigeration for uses such as in magnetic resonance imaging systems wherein an oil-free compressor operating at a higher frequency generates pulsing gas which undergoes a frequency reduction and drives the pulse tube system at a more efficient lower frequency.
摘要:
A method for operating a cryocooler which provides opportunity for timely intervention prior to failure thus enhancing the reliability of the provision of the refrigeration wherein contaminant concentration downstream of a compressor but upstream of the cryocooler is monitored and the time rate of change of the contaminant concentration is used to calculate a service time.
摘要:
A method for operating a cryocooler which provides opportunity for timely intervention prior to failure thus enhancing the reliability of the provision of the refrigeration wherein temperature trending of at least one cryocooler component or the refrigeration load is monitored and used to calculate a service time.
摘要:
Disclosed is a detector device with a cooling system having first cooling means (20,30) for providing a first cooling temperature, said first cooling means comprising a two-stage pulse tube cooler system, in which a first pulse tube cooler (20) pre-cools a second pulse tube cooler (30), and second cooling means (82,83,85,86,87) for providing a second cooling temperature, which is lower than the first cooling temperature, said second cooling means being pre-cooled by said first cooling means. Furthermore, the detector device comprises detector means (60) for detecting particles, radiation or fields with a sensor based on a low temperature effect, said detector means being thermally coupled to said second cooling means. Thus, a detector device is provided with a comparably simply structured cooling system whereby sensors can be operated which have a good energy resolution and which can be quasi anywhere on account of the low complexity of the cooling system. (FIG. 1)
摘要:
A rotary valve of a multivalve type pulse tube refrigerator includes: a stationary seat; a rotary disk to change a coolant path by rotating while surface-contacting with a face of the stationary seat; a plurality of first ports provided in the face of the stationary seat to supply a high-pressure coolant to a regenerator and exhaust a low-pressure coolant from the regenerator; and a plurality of second ports provided in the face of the stationary seat to supply a high-pressure coolant to a pulse tube and exhaust a low-pressure coolant from the pulse tube. The first ports are arranged in a first circular track area in rotation symmetry with respect to the center of the face. The second ports are arranged in a second circular track area in rotation symmetry with respect to the center of the face.
摘要:
A cryogenic refrigerator includes a displacer that is reciprocably mounted within a cylinder; a spool valve that is connected to the compressor and performs switching between an intake mode where a high-pressure refrigerant gas is supplied from the compressor to the cylinder and an exhaust mode where a low-pressure refrigerant gas within the cylinder is made to flow back to the compressor; and a drive unit that drives the spool valve. The spool valve has a valve body, and a drive rod that moves relative to the valve body and is integrated with the spool. The drive unit performs driving so that the magnitude of a speed when the drive rod moves from a top dead center to a bottom dead center is different from the magnitude of a speed when the drive rod moves from the bottom dead center to the top dead center, at the same displacement position.
摘要:
The problems of reducing the torque required to turn the valve, eliminating wear dust, and extending the life of the valves in Gifford McMahon (G-M) type multi-port pulse tube refrigerators are solved by using a rotary spool valve having radial clearance to control flow to and from the regenerator, and using face seal ports on the end of the spool to control flow to and from the pulse tubes.
摘要:
A rotary valve unit which reduces the torque required to turn the valve disc, and the amount of wear dust that is blown into the cold head, using differential gas forces to keep the valve disc in contact with the valve seat, and which enables larger diameter valve discs to be utilized for multi-ported pulse tubes that have less force on the face of the valve disc, resulting in reduced torque and reduced wear rate.