GB725580A - Improvements in or relating to high vacuum oil diffusion pumps - Google Patents

Abstract

725,580. High vacuum diffusion pumps. EASTMAN KODAK CO. March 4, 1953 [March 5, 1952], No. 5985/53. Class 71. In an oil diffusion pump having a central detachable chimney 35 fitted with a nozzle forming cap 42 and seated on the base 12 of a vertical cylindrical casing 17, the upper end of the chimney 35 is secured against excessive axial displacement by means of a spring clip 44 which loosely encircles an upstanding post 43 secured to the chimney so as to allow lateral movement thereof and bears against the inner wall of the casing 17. The chimney 35 is surrounded by a concentric capped chimney 34 which also seats on the base 12 to form an annular boiler compartment in communication with the central compartment through a notch 37. An outer capped chimney 33 is secured to the chimney 34 by spacers 38 and dips into a gutter 18 below a forepressure arm 22 having a drain cock 30. Tarry residues and decomposition products of the pump fluid collecting in the central portion of the boiler may be removed through a drain 48, and gases distilled therefrom traverse a tube 53 leading to the chimney 34.