Patent GB-758888-A (GB)
Title: Dry-cleaning systems, methods and apparatus
Inventor: GATES CHARLES ALFRED
IPC: D06F43/08
Filed: 1954-07-27
Abstract: In a dry cleaning system comprising a washer, pump and a filter, filter powder in suspension in solvent is fed into the stream of solvent from the washer and button trap and into the suction line of the pump, whereby without going through either the washer or trap it is carried direct by the pump to the filter in a uniform manner and rate.  The solvent is taken from the system and a filter powder feeding receptacle used for feeding the suspension to the system, the powder being itself preferably supplied to the feeding receptacle by a powder metering device.  In a suitable closed-circuit re-cycling system, clean solvent from a pipe 21 is admitted <PICT:0758888/III/1> <PICT:0758888/III/2> to the washer 20 and soiled solvent withdrawn therefrom through pipe 22 having a valve 23 and button trap 24 to a pipe 25 leading to the suction inlet of the circulating pump 26.  The pump forces the solvent through a pipe 27 into the upper part of the filter 28 from which the clean solvent is returned to the washer through pipes 29 and 30.  A spring loaded valve 33 is provided to produce a pressure in the pipe 30 for operating the powder feeder and causing a back pressure on the filter.  The filter comprises the usual hollow filter recess 34.  The filter powder suspension is fed into the suction pipe 25 of the pump from a feeder comprising an outer housing 40 with an inner float chamber 43 both of which are supported by pipe connections to the pump suction pipe 25, the support 49 of the inner chamber being the casing of an outlet valve. The powder is fed into the housing 40 through an opening 51 and slides into a bath of solvent in the housing fed thereto from pipe 30 through an inlet valve 82.  These inlet and outlet valves are controlled by a float 52, Fig. 2, in the float chamber raised and lowered by the solvent which action through a lever system raises and lowers a valve operating rod 67 attached to the outlet valve.  The rod 67 passes through the end of the inlet valve operating lever 68, the lever 68 being pulled down by the descent of the rod 67 and raised by a spring in the inlet valve. The inlet valve 82 is arranged in a pipe 85 connected through a pipe 86 to the clean solvent pipe 30.  When the lever 68 is pulled down it opens the valve 82 against its spring.  In operation with both valves 49 and 82 open, when the solvent enters faster than its discharge the float rises and closes the inlet valve 82 and further opens the discharge valve 49 and vice versa.  In equilibrium the float permits the increased fluid to flow through the feeder continuously at a uniform rate.  Air in the system rises in the filter and entrained with solvent is bled off through a pipe 90 to mix with the solvent intake in pipe 85, the air passing to the atmosphere through the open powder feeder.  The powder may be supplied to the open top of the feeder preferably with the use of a powder metering device and a bag-type hopper therefore.  Detailed description is given of a metering device giving measuring charges by volume and also a metering device giving such charges by weight and both may be used together.