JPH035727Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a valve used in an ultra-high vacuum system, and particularly to a metal disk mounted on the valve facing the valve seat.

(Prior Art) Conventionally, ultra-high vacuum valves used in ultra-high vacuum systems are designed and manufactured to withstand high-temperature baking. Further, the ultra-high vacuum valve is usually configured such that the valve chamber is partitioned by a metal diaphragm, a metal bellows, or the like in order to maintain airtightness.

FIG. 3 is a side sectional view showing an example of an ultra-high vacuum valve using the metal diaphragm described above. Therefore, it is attached to the valve body 4 so as to be movable up and down so as to be isolated from the valve chamber 7, and the valve body 2 is raised and lowered by operating the handle. In the figure, 5 is an operating handle that presses the top of the valve body 2 via a ball, 6 is a spring that constantly lifts the valve body 2 in the valve opening direction, and 8 and 9 are communicated with the valve chamber 7. The gas inlet pipe and gas outlet pipe are shown.

In the conventional metal disk 2a used in the above-mentioned ultra-high vacuum valve, as shown in the enlarged view of the main part in FIG. 3a, the opposing annular surface of the valve seat 1 is formed into a flat shape, The valve seat 1 was hermetically sealed by the flat metal disk 2a.

(Problems to be Solved by the Invention) The conventional metal disk for ultra-high vacuum valves described above has the following problems.

(i) Since the surface facing the valve seat 1 is formed in a flat shape, during use of the valve, the surface facing the valve seat tends to wear unevenly and come into contact with the valve seat. Surface contact becomes difficult and leakage is difficult to stop.

(ii) If baking is performed to increase the degree of vacuum, the metal disk 2a will be thermally deformed and will no longer be able to maintain surface contact with the valve seat 1, making it more likely to leak.

(iii) As mentioned above, it is easy to leak, so the unit tightening load of the valve seat must be increased.

(iv) Manufacturing is not easy because the flatness of the joint surface between the valve seat 1 and the metal disk 2a must be increased.

(v) Once a leak occurs, it is difficult to stop the leak because it is difficult to create an accurate flat surface even if the metal disk is replaced.

The technical objective of the present invention is to solve each of the above-mentioned problems.

(Means for Solving the Problems) In order to solve the problems of the prior art described above, the present invention provides an annular protrusion on the surface of the metal disk facing the valve seat, and an annular protrusion on the protrusion. form a dent,
It is characterized in that the recess is plated with a metal having good malleability so as to be held by the recess, protrude from the surface of the annular projection, and come into contact with the valve seat.

In actual practice, it is desirable that the annular recess is formed to have an arcuate cross section, and that gold is preferably used as a metal with good malleability.

(Function) With the present invention configured as described above, the malleable metal plated in the annular recess of the metal disk so as to protrude from the surface of the annular protrusion is able to prevent the valve from opening and closing as the valve opens and closes. Even when subjected to thrust, the tendency to shift from side to side is prevented and it remains within the concave area. Therefore, the plating does not peel off.

In addition, the metal inside the annular recess has good malleability, so even when subjected to thermal deformation due to valve thrust or baking, it tends to spread from side to side, fitting well to the valve seat and maintaining a good seal with the valve seat. There is.

(Example) Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a side view showing a part of a metal disk for an ultra-high vacuum valve in cross section showing one embodiment of the present invention, and FIG. 2 is an enlarged sectional view of section A in FIG. Note that FIG. 1 corresponds to section B in FIG. 3, and the metal disk of the present invention is used as an ultra-vacuum valve by being assembled as shown in FIG. 3, for example.

In the figure, an annular protrusion 13 is integrally provided on the surface of the metal disk 12 facing the valve seat 11, and the annular protrusion 13 has a recess 14 having an arcuate cross section over the entire circumference. It is formed in a ring shape. Further, in the annular recess 14, a metal 15 with good malleability such as gold is formed by plating at a height such that it protrudes above the end surface of the annular protrusion 13 and comes into contact with the valve seat 11. , when the valve is closed, the top 15a of the raised protrusion of the metal 15 and the valve seat 11
and are in close contact all around the circumference.

According to this embodiment, when the valve is closed, in the illustrated state in which the metal disk 12 descends together with the valve body and comes into contact with the valve seat 11, the metal disk 12 has an annular recess as described above. Metal 15 in 14
The contact between the valve seat 11 and the valve seat 11 provides a tight seal over the entire circumference. Even if the metal 15 is deformed by the valve thrust associated with the valve opening/closing operation or by the heat of baking, the metal 15 is highly malleable, so it can conform well to the surface of the valve seat 11. Seal performance is maintained. Also, the metal 15
Since it is formed so as to swell into the recess 14, it is prevented from shifting from side to side even when receiving valve thrust, and therefore the plating does not peel off, resulting in high durability.

Further, as mentioned above, the metal disk 12 is
The top 15a of the metal 15 plated so as to bulge inside the annular recess 14 is in contact with the valve seat 11 and sealed, so that when the valve is closed, the valve thrust is applied from the metal disk 12 to the valve seat 11. Since the closing force is concentrated on the plated metal top 15a, the sealing force can be increased.

On the other hand, the reaction force applied to the metal seal 12 from the valve seat 11 is transmitted from the top 15a of the metal 15 through the recess 14 having an arcuate cross section into the metal disk 12 in a radial direction, so that the force can be dissipated.

In the above embodiment, the metal 15 plated in the recess 14 may be other than gold, such as silver, aluminum, platinum, or copper, as long as it has good malleability, and the cross-sectional shape of the annular recess 14 may also be Of course, the shape is not limited to an arc shape. Further, there is no problem even if a part of the metal plated in the recess 14 protrudes outside the recess.

(Effects of the invention) As explained above, the invention provides the following effects.

(i) Since the recess formed on the surface of the metal disk facing the valve seat is plated with a highly malleable metal, the plated metal will not escape out of the recess even when subjected to valve thrust. Therefore, it has good durability.

(ii) Since the metal plated in the recess is made of a metal with good malleability, even if deformation occurs due to the heat of baking, the metal disk can fit well into the valve seat, thus improving sealing performance. is good.

(iii) The valve seat surface is sealed with a malleable metal plated inside the annular recess, making it easy to manufacture, and in the event of leakage, the sealing performance can be easily restored by replacing the disc. do.

[Brief explanation of the drawing]

Fig. 1 is a partially sectional side view of a metal disk for an ultra-high vacuum valve showing an embodiment of the present invention, Fig. 2 is an enlarged sectional view of section A in Fig. 1, and Fig. 3 shows a metal diaphragm. FIG. 3a is a side sectional view of the ultra-high vacuum valve used, and FIG. 3a is an enlarged sectional view of the main part of section B in FIG. 11... Valve seat, 12... Metal disk, 13
...Annular protrusion, 14...Annular recess, 15...Metal with good malleability.

Claims (1)

[Claims for Utility Model Registration] 1. An annular protrusion is provided on the surface of the metal disk facing the valve seat, an annular recess is formed in the protrusion, and the above-mentioned A metal disk for ultra-high vacuum valves, characterized by plating a highly malleable metal so that it protrudes from the surface of the annular protrusion. 2. The metal disk for an ultra-high vacuum valve according to claim 1, wherein the metal with good malleability is made of gold. 3. The metal disk for an ultra-high vacuum valve according to claim 1 or 2, wherein the annular recess has a circular arc cross section.