Sealing plate with a filter for a high pressure liquified gas cartridge having a syphon tube

Abstract: This sealing plate with a filter for a high pressure liquified gas cartridge having a syphon tube is to prevent cutting dusts from flowing out with liquified gas. A filter (1) is formed like a column with a groove (3) which has an opening (2) at one end in its axial direction. This filter (1) is attached to a main body (4), by facing the opening (2) of the groove (3) to the inner plane of the main body (4) and pressing the outer periphery of the filter (1) on the inner plane of an annular leg (5) of the main body (4). Thus, a sealing plate with a filter for a high pressure liquified gas cartridge having a syphon tube is formed.

Description: BACKGROUND OF THE INVENTION 1. FIELD OF THE INVENTION The present invention relates to a sealing plate with a filter for a high pressure liquified gas cartridge having a syphon tube. 2. DESCRIPTION OF THE PRIOR ART A cartridge of the type having a double safety device which regulates quantity of flow of high pressure gas to prevent a cartridge from flying by reaction and having a filter on a sealing plate for preventing an orifice from being clogged, has been shown in No.61-274200(Fig.8) and also No.62-17500 of the Japanese Patent Publication, both of which were filed prior to the present application. A high pressure gas cartridge to which the aforesaid filter is applied is not worked internally after once washed, and the cartridge is to only be charged with a perfectly gasified high pressure gas. Therefore, there are rare cases where cutting dusts and the like remain in a cartridge and moreover, as a flowing substance in the cartridge is a perfectly gasified gas only, the cutting dusts and the like which are carried by the gas are limited within those which float and slightly stick to the inner wall of the cartridge, and even the total quantity of them is trifling. On the contrary, in a case of a cartridge to be charged with a liquified gas, a cartridge is often used in an upstanding state, whence a syphon tube is set in a washed cartridge so as not to emit gaseous parts previously to liquified parts. In this case, it takes the form that a syphon tube is fitted on a portion of a cartridge. Therefore, by friction between the outer circumferential plane of a syphon tube and the inner wall of a cartridge, micro dusts are apt to stick to the connecting portion and the like between the outer periphery of the top plane of the syphon tube and the cartridge. As liquid has a flowing resistance larger than that of gas, when liquid moves in a cartridge, the liquid takes these dusts therein. When the liquid flows out of a cartridge, the liquid carries these dusts therewith, and which often causes a clogging of a filter provided to a valve. In such a case, a desired quantity of flow of gas flow becomes unobtainable. Furthermore, in filters of a valve, there are types which are not replaceable or are difficult to replace, therefore, long and stable use of a filter has been desired. It might be thought that it would be good to wash a cartridge after a syphon tube has been set thereto, but, in fact, washing a cartridge after the setting of a syphon tube has not been done. That is why, even if a cartridge is washed, when the cartridge is inclined to drain after washing, a large portion of the washing fluid does not flow out because of the syphon tube and remains in the cartridge, thus the dusts and the like cannot be drained. Accordingly, in a sealing plate with a filter for a high pressure liquified gas cartridge having a syphon tube, it has been a problem how to prevent inner dusts and the like from flowing out. The present invention solves the problem, by fitting a filter, which is formed like a column having a groove which has an opening at one end in the axial direction thereof, onto the main body, by directing said opening of the groove to the inner plane of the main body and possitively fitting outer circumferential plane of said filter onto an inner circumferential plane of an annular leg of the main body. A sealing plate in which the present invention is embodied is placed on an opening of a cartridge with a syphon tube and liquified gas, such as liquified carbon dioxide gas, is charged therein, Then the sealing plate is welded to the cartridge. When the cartridge is attached to an opening device and the sealing plate is pierced, the liquified gas flows in the syphon tube, passes through a filter, and flows out of the cartridge. Quantity of flow of the liquified gas is not restrained by the filter. The liquified gas from a valve is supplied to works, such as washing or cooling of an electronic circuit, which use the gas. The dusts and the like, which have passed through the syphon tube with the liquified gas, are caught by the filter when they pass therethrough, and only purified gas flows in the valve. Therefore, the filter, which is provided to the valve, is not clogged in almost cases, and an expensive valve can be used long and stably. SUMMARY OF THE INVENTION According to this invention there is provided a sealing plate for a high pressure gas cartridge, the plate comprising a main body with an annular leg and a filter, wherein the cartridge is for liquefied gas and has a syphon tube, and the filter is made of sintered metallic powder and is formed like a column having a groove which has an opening at one end in an axial direction thereof, wherein the filter is fitted onto the main body with an outer circumferential surface of said filter positively fitted into an inner circumferential surface of the annular leg, and the opening directed towards an inner plane of the main body which covers it. Other and further objects of the present invention will be spontaneously apparent from the following description of embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig.1 is a side view of an embodiment of a high pressure liquified gas cartridge with a syphon tube, in which an opening portion thereof a part of the cartride is omitted and semicut, and Fig.2 is an enlarged cut off view of the sealing plate. DETAILED DESCRIPTION OF THE INVENTION 1 is a filter, and which is formed of metalic powder like a column which has a groove 3 with an opening 2 at one end in an axial direction. If stainless powder is used as metalic powder, corosion resistance is elevated. 4 is a main body, and which is an ordinal type having an annular leg 5 on one plane and a safety device 6 on the other. The filter 1 is attached to the main body 4, by directing its opening 2 of the groove 3 face to the inner plane of the main body 4 and by fitting the outer periphery of the filter 1 on the inner circumferential plane of the annular leg 5. In this state of attachment, the groove 3 forms a space inside the main body 4, and the space makes the movement of a needle to pierce the main body 4 easy. 7 is a cartridge, and, in the inner bore of a neck 8 of which the upper portion of a syphon tube 9 made of metal or plastic fits, and also the lower portion of the syphon tube reches near the bottom of the cartridge 7. As usual, the outer underside periphery portion of the main body 4 is put on the top of an opening portion 10 of the cartridge 7 and liquified gas is charged in the cartridge 7. Then the main body 4 and the cartridge 7 are welded to each other, and the opening portion 10 is sealed closely. After the neck 8 of the cartridge 7 has been attached to an opening device which, as usual, is provided to a valve, the main body 4 is pierced. The liquified gas flows up in the syphon tube 9 and flows out, controlled by the valve, to the demand side. When liquified gas is charged in a cartridge and the cartridge is vibrated during its transportation, some of dusts, such as metalic or plastic powder, which stick to an end portion between the syphon tube 9 and the neck 8, are taken in the liquified gas. The dusts also flow up in the syphon tube 9 carried by the gas, but, as meshes of the filter 1 are less than each dust, the dusts cannot pass through the filter and are caught thereby. Whereas the only purified liquified gas flows in a valve, and a filter which is provided to the valve is not clogged. The purified liquified gas is controlled by a valve and used for cleaning or cooling a semiconductor.

Claims: A sealing plate for a high pressure gas cartridge (7), the plate comprising a main body (4) with an annular leg (5) and a filter (1), characterized in that the cartridge is for liquefied gas and has a syphon tube (9), and the filter (1) is made of sintered metallic powder and is formed like a column having a groove (3) which has an opening (2) at one end in an axial direction thereof, wherein the filter (1) is fitted onto the main body (4) with an outer circumferential surface of said filter (1) positively fitted into an inner circumferential surface of the annular leg (5), and the opening (2) directed towards an inner plane of the main body (4) which covers it.

Inventors: SATO MASAO, SATO, MASAO
Applicants: NIPPON TANSAN GAS CO LTD, NIPPON TANSAN GAS CO., LTD.
Application year: 1993
Main classification: F17C13
IPC codes: F17C13, F17C1