GB921684A - Improvements in and relating to machines for filling containers such as cans or bottles with liquid - Google Patents

Abstract

921,684. Rotary filling machines for cans &c. CROWN CORK & SEAL CO. Inc. Sept. 12, 1960, No. 31399/60. Class 125(2). [Also in Group XXIX]. In a counterpressure filling machine, e.g. for carbonated liquids, the gas displaced from the container during the entry of liquid is vented to a second pressurised reservoir 30, 31, separate from the pressurised liquid reservoir 18 from the head space of which the counterpressure is obtained, a constant pressure differential being maintained between the reservoirs. The machine is a revolving table type with containers carried by revolving arms C into position beneath filling heads 114. Each filling head 114 is connected to the reservoir 18 by counterpressure and liquid supply pipes 120, 144 and to the reservoir 30 by vent pipe 164, which pipes are connected in correct sequence to the container C by a rotary valve 16 actuated through trip arms 44, 46, by stationary cams. Reservoir 30 is connected to reservoir 18 through a pressure control valve 248 which maintains a constant pressure differential therebetween, a check valve in valve 248 permitting gas to flow only from chamber 18 S to chamber 30. A pressure relief valve on reservoir 30 is also controlled by a diaphragm in the device 248 loaded by the pressure on the two reservoirs. The rotary valve 16 comprises a disc 41, Fig. 3, mounted on a fixed bolt 65 and actuated by the arms 44, 46, through a cap 42 keyed to the disc by a spigot 84, springs 94 holding the disc against its seat 60. Each filling head, Fig. 25, has a counterpressure supply passage leading to orifice 24, liquid passages 216 each connected to a plurality of nozzles 226, and a vent passage 210 leading from the orifice 204. Filling is terminated when a float valve 292 closes the orifice 204. The valve 292 comprises two plastic hemispherical sections 302, 304, Fig. 31, of different thickness so that the ball always floats with the thin section 302 uppermost and the seam 306 is prevented from engaging the seat. In a modification, Fig. 28, the counterpressure gas is supplied through passage 200<SP>1</SP> to a number of passages 272 situated between the nozzles 226. The vent passage 210<SP>1</SP> includes a spring-loaded valve 282 which is opened by a cam 284 during the first portion of the period in which the counterpressure is built up in the container C, whereby the air displaced from the container is vented to atmosphere. The valve 282 then closes so that during the filling step, the displaced counterpressure gas is vented to the chamber 30, Fig. 1, as previously described. Specification 522,229 and U.S.A. Specificacation 2,097,107 are referred to.