GB562409A - Improvements in rotary pumps - Google Patents

Abstract

562,409. Rotary pumps. BANCROFT, F. E., and METROPOLITAN - VICKERS ELECTRICAL CO., Ltd. Jan. 23, 1943, No. 1195. [Class 110 (ii)] The pump comprises a cylindrical casing 1a, inlet and outlet ports 1e, 1d, a diaphragm 2 of pliable and preferably flexible material such as rubber, and a rotor 18 mounted on a crank-pin 4 and caused to roll around the inside of the diaphragm. The diaphragm is clamped at the ends by rings 3, 4 and against the casing la by a strip 5 of spring steel or the like. End plater 7; 8 have gaskets 9, 10. The crank-shaft 12 is mounted in ball or roller bearings 13, 13a in a housing 11 which is coaxial with the pump' body to which it is welded. A balance weight 14b is fixed to the crank-pin 14. The shell 18 and web 17 of the rotor may be built up of parts and mounted on a bearing 15 which may have an adjustably eccentric sleeve. Oil is supplied through a pipe 24 to oil seals 21, 22. Any oil leaking along the crank-shaft 12 is thrown off and passes through a pipe 26 to a trap 25. Grease is preferably used for lubrication of the crank-pin and its bearings. The space 20 may have its pressure reduced below atmospheric to even up the pressures on each side of the diaphragm by suction through a pipe 19. When the pump delivers against a pressure ratio of about 5 : 1, a non-return valve may be provided at the outlet orifice. The outlet orifice may be smaller than the inlet orifice. In modified arrangements, the peripheral walls of the rotor 18 are parallel or convex with regard to the axis. Fig. 5 shows a further type of pump having two rollers 56, 57 mounted on arms secured to the driving shaft.