JPH0364715B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a buffling device applied to a cryopump for evacuation.

Conventionally, as shown in the first diagram, this type of apparatus has been developed using a cryopump having an annular structure, which is composed of an upper half part _a1 of which diameter gradually decreases upward, and a lower half part _a2 which gradually decreases diameter downward. It is known that a plurality of baffle members a having different diameters are prepared, and these baffle members are arranged concentrically so that adjacent buffle members have an overlap part b in the vertical direction, but in this case , the upper half a ₁ and the lower half
A ₂ is generally made asymmetrically with respect to each other as shown in the figure, and in such a structure, the upper and lower openings of each member a have a smaller diameter than the outer diameter of the buttful member located inside, and thus each buttful When the members are prepared separately in advance, it is impossible to assemble them into each other as is, and in other words, the manufacturing thereof becomes troublesome.

The object of the present invention is to provide a buff-full device free of such inconveniences, and is a cryopump consisting of an upper half whose diameter gradually decreases upward and a lower half whose diameter gradually decreases downward. A plurality of annular buttful members with different diameters are prepared, and these are arranged concentrically so that adjacent buffle members have overlapped portions in the vertical direction. The upper and lower halves are made asymmetrical with respect to each other, and one of the upper and lower openings is configured to have a larger diameter than the outer diameter of the buttful member located inside, and the inside Each baffle member can be inserted freely.

Embodiments of the present invention will be explained with reference to attached drawings.
The baffle device shown in FIG. 2 is a cryopump annular buffle member 1 consisting of an upper half 1a whose diameter gradually becomes smaller toward the top and a lower half 1b whose diameter gradually becomes smaller toward the bottom. These baffle members 1, 1 are arranged concentrically so that the adjacent baffle members 1, 1 overlap each other in the vertical direction.
It was made to have.

Although this point is not particularly different from the conventional one, according to the present invention, the upper half 1a and the lower half 1b of each member 1 are made asymmetrical with respect to each other, and the upper and lower openings 2a,
One of the baffle members 2b is configured to have a larger diameter than the outer diameter D of the other buffle member located inside, and each buffle member 1 can be inserted into the inside thereof through the large diameter opening.

To explain this in detail, in the illustrated example, three buffle members 1c, 1d, and 1e are incorporated to form a buffle device, and each buffle member 1 has a length L1 of its upper half 1a and a length _L1 of its lower half. The length _L2 of the portion 1b is made different from each other to make it asymmetrical, and the upper and lower openings 2a and 2b have their lower openings 2b connected to other buttful members located inside, for example, in the case of the middle buttful member 1d, the lower openings 2a and 2b The opening 2b is configured to have a larger diameter than the outer diameter _D1 of the buffful member 1c adjacent to the inner side, so that the baffle member 1c can be freely inserted into the inner side through the large diameter opening 2b. In the drawings, reference numeral 3 indicates a disc-shaped buttful plate provided within the annular shape of the innermost btsful member 1c. An overlap portion B is formed with the portion 1a.

As described above, according to the present invention, the upper half and the lower half of each buffful member are made asymmetrical with respect to each other, and one of the upper and lower openings is made larger in diameter than the outside diameter of the buffful member located inside. Because it is possible to insert other bulky parts inside through the large diameter opening,
Each buttful member can be prepared separately in advance and then assembled one after another, making the production of the buttful device simple and easy. Overlapping parts are ensured between each buttful member to function as a buttful. It has the effect of not damaging the

[Brief explanation of drawings]

FIG. 1 is a cutaway side view of a conventional example, and FIG. 2 is a cutaway side view of an embodiment of the present invention. 1, 1c, 1d, 1e...battery member, 1a...
Upper half, 1b...lower half, 2a...upper opening, 2b
...Lower opening, A...overlap portion, D...outer diameter.

Claims (1)

[Claims] 1. Prepare a plurality of cryopump annular buttful members with different diameters, each consisting of an upper half that gradually becomes smaller in diameter toward the top and a lower half that gradually becomes smaller in diameter toward the bottom. In a device in which adjacent buffful members are arranged concentrically with each other and have overlapped portions in the vertical direction, the upper and lower halves of each buffful member are made asymmetrical with respect to each other so that the upper and lower openings are A baffle device for a cryopump, in which one buffle member is configured to have a larger diameter than the outer diameter of the buffle member located on the inside, and each buffle member on the inside can be freely inserted through the large-diameter opening.