JPH0550085U - Cryopump - Google Patents

Abstract

(57) [Abstract] [Purpose] A cryopump has a structure that enhances cooling efficiency to enhance the vacuum exhaust effect. [Structure] Instead of a baffle provided in a conventional cryopump, a spiral coil 4 is used, and liquid nitrogen is circulated in the spiral coil 4 for cooling. [Effect] By circulating the liquid nitrogen, the cooling effect in the pump 1 is enhanced, and the condensation effect of gas molecules is enhanced,
Evacuation capacity is improved.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a pump that achieves a high degree of vacuum, and more particularly to a structure in which the inside of the pump of a cryopump is improved.

[0002]

[Prior Art]

 Conventionally, as shown in FIG. 2, a cryopump makes a cryogenic temperature (about −250 ° C.) by adiabatic expansion of high-pressure helium gas in the refrigerator 1 in the central part of the pump, and this temperature is indicated by an arrow in the figure. As described above, the cooling temperature is conducted and transmitted to the inner panel 3, and for example, the baffle 5 made of SUS is cooled.

[0003]

[Problems to be solved by the device]

 By the way, in the conventional internal structure of the cryopump described above, since the cooling location is one location of the refrigerator 1, it takes time for the cooling temperature to reach the baffle 5, and the cooling temperature in the pump is also about -190 ° C. Was the limit.

Further, when a heat load is applied from the outside, the temperature of the baffle 5 rises, and the ability to condense gas molecules decreases, so that there is a drawback that a high degree of vacuum cannot be obtained.

[0005]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention provides a cryopump in which a cryopanel connected to a refrigerator and a spiral coil for circulating liquefied gas are provided in a pump.

[0006]

[Action]

 According to the above configuration, a spiral coil is installed at a location corresponding to a conventional baffle, and liquid nitrogen is introduced into the spiral coil, so that the pump inlet with the spiral coil can be forcibly cooled to about -200 ° C. Therefore, the effect of condensing gas molecules is enhanced, and the evacuation capacity is improved.

[0007]

【Example】

 The present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing a cross section of a part of a cryopump showing an outline of the present invention. In the figure, 1 is a refrigerator, 2 is a cryopanel, 3 is an internal panel, and 4 is preferably a copper spiral coil.

Next, the operation of the above cryopump will be described. First, by introducing liquid nitrogen into the spiral coil 4 from the outside of the pump as shown by the arrow in the figure, the surface of the spiral coil 4 is cooled to about -200 ° C. In this way, the cooling effect at about -10 ° C is improved compared to the conventional pump, and the condensation effect of gas molecules is improved. Further, since the pump inlet with the spiral coil 4 is forcibly cooled, it is possible to avoid the temperature rise in the pump due to the heat load from the outside, and it is possible to maintain the cooling capacity of the refrigerator 1 with a margin. There is an advantage that.

Further, by adding a means of introducing liquid nitrogen to the spiral coil 4 in addition to the conventional refrigerator 1 as a cooling portion, from room temperature to an extremely low temperature at which pump performance can be exhibited. There is also an advantage that the cooling time can be shortened.

The spiral coil 4 can be arranged along the baffle 5.

[0012]

[Effect of the device]

 As described above, the present invention preferably adds a spiral coil to a conventional cryopump and causes liquid nitrogen to flow in the cryopump to improve the cooling capacity of the pump, thereby improving the vacuum exhaust capacity, and the external coil. It has the effect of improving durability from load and shortening the time from the pump stopped state to when it can be used.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing an outline of a cryopump of the present invention.

FIG. 2 is a partially cutaway perspective view of a conventional cryopump.

[Explanation of symbols]

 1 Refrigerator 2 Cryopanel 3 Internal panel 4 Spiral coil

Claims (2)

[Scope of utility model registration request] 1. A cryopump in which a cryopump connected to a refrigerator and a spiral coil for circulating a liquefied gas are provided side by side in the pump. 2. A cryopump, wherein the spiral coil according to claim 1 is made of copper.