| 摘要 |
<p>918,520. Diffusion pumps; baffles. IPSEN INDUSTRIES Inc. Sept. 1, 1961 [Sept. 13, 1960], No. 31470/61. Class 71. [Also in Group XXIX] A combined cold trap and vacuum valve comprises a tubular inlet portion 11, Fig. 1, a tubular intermediate portion 13 which is coaxial with, and larger in cross-sectional area than, a tubular outlet portion 12, a valve disc 17 which is disposed within the intermediate portion and seats on a shoulder 14, a flange 30 projecting inwardly over the valve disc periphery, a baffle 28 disposed between the flange and the shoulder and means 31 for cooling the baffle. Inlet portion 11 communicates with a chamber to be evacuated e.g. a heat-treating furnace and the outlet portion 12 is connected to pumping apparatus e.g. a mechanical pump and an oil diffusion vapour pump. Air or vapours being evacuated or oil vapours which may backstream are deflected outwardly to strike either the corrugated baffle 28 or shoulder 14. Water or liquid nitrogen is circulated as a coolant through tube 31 and, in a modification, through an additional coil disposed within the baffle corrugations. The cross-sectional areas of the inlet and outlet portions and of the annular space around the valve disc are substantially equal.</p> |
