摘要:
A refrigerating machine having a displacer reciprocable in a hollow space having a substantially-closed end for the refrigerating operation has a spring between the displacer and the substantially-closed end of the hollow space for damping vibration and noise of the displacer reciprocation.
摘要:
A cryopump has a two-stage refrigerator in a housing with a pumping surface area in thermal communication with each stage of the refrigerator for gas-pumping by adsorption or absorption when the refrigerator is operated. A roughing vacuum pump provides a pressure of from about 1 to about 10.sup.-3 mbar to the housing and at least the pumping surface area of the second refrigerator stage is heated sufficiently to prevent gas adsorption or absorption thereon before the cryopump is operatively connected to a space to be evacuated therewith as a starting method for improving the cryopumping of, particularly, helium and a regenerating method after use of the cryopump.
摘要:
A method and circuit for measuring and displaying a parameter, in which the parameter is sensed by means of a sensor which supplies an output voltage representative of the value of the parameter, the output voltage is compared with a comparison voltage associated with the sensor response characteristic, and a display is produced on the basis of the result of the comparing step. The comparison is effected by supplying the output voltage from the sensor to a first input of a comparator, supplying the comparison voltage to a second input of the comparator, and varying the comparison voltage between successive values extending over the output voltage range of the sensor. The display is produced by providing a succession of parameter value signals each associated with a respective comparison voltage value, supplying each parameter value signal to a latch device in synchronism with occurrence of the associated comparison voltage value, and conducting to a display device from the latch device the parameter value signal which is associated with the comparison voltage value that corresponds to the output voltage value of the sensor.
摘要:
A displacer for low-temperature refrigerating machines having a regenerator disposed in a hollow space of the displacer, wherein the regenerator is formed at least in part of a sintered material, preferably sintered bronze spheres.
摘要:
The invention relates to a process for regenerating a cryopump (1) that is equipped with an inlet valve (33), with cold surfaces (6, 8, 11) which have a temperature during operation of the pump that effects the condensation and/or adsorption of gases and which are heated for the purpose of regenerating them, the cryopump further including a backing pump (45) that is connected with the pump interior (9) by way of a valve (44). In this process, heating of the cold surfaces begins if the inlet valve (33) is closed and the connection between the pump interior (9) and the connected backing pump (45) is blocked so that, in addition to the temperature of the cold surfaces, the pressure in the pump interior also rises to values that lie above the corresponding values of the triple point of the gas to be removed. The removal of the precipitates released from the cold surfaces is effected in liquid and/or gaseous form through a conduit (46) equipped with a regeneration valve (47) that is actuated as a function of the pressure in the pump interior (9).
摘要:
A two-stage cryopump having a refrigerator including a first stage and a second stage being colder than the first stage; a condensation member having a condensation surface; a first coupler for connecting the condensation member to the second stage in a thermally conducting manner; an adsorption member having an adsorption surface and being spaced from the condensation member; and a second coupler for connecting the adsorption member to the second stage in a heat conducting manner. There is further provided a heater for heating the adsorption member during time periods for regenerating the adsorption member. The second coupler is so designed that it thermally sufficiently insulates the adsorption member from the second stage and from the condensation member at least during heating periods of the adsorption member, for preventing heating the condensation member by the heater.
摘要:
The invention relates to a cryopump having a casing (1), a gas inlet opening (8) to which a chamber (30) can be attached through a valve (31), a vacuum pump (18) connected through a valve (16) to the casing, a two-stage refrigerator (4) in the casing as cold source, and pumping surfaces (7, 9, 12, 13) which, on both of the refrigeration stages (5, 11) of the refrigerator, are equipped with an electrical heating means (23, 24). To achieve a great shortening of the time required for regeneration and start-up it is proposed that a sensor (41) be provided to monitor the pressure within the pump casing, and that a control unit (28) be present by which the operation of the cryopump can be monitored and controlled on the basis of the signals supplied by the sensor.