| 摘要 |
<p>950,461. Washing vehicles. HOMESTEAD VALVE MANUFACTURING CO. March 22, 1960 [March 18, 1960], No. 10203/60. Heading B7J. In apparatus for spraying a vehicle with a cleaning liquid, the liquid is drawn from a tank 2, Fig. 1, by two pumps 8, 24, and is passed through a coiled heating pipe 17 containing an electric heater 33 to a line 18 carrying a discharge nozzle 21, and the inlet to the pump 24 is controlled by a valve 22 so that the rate of flow of liquid through the heater may be regulated to adjust the temperature and pressure of the discharged spray. The pumps 8, 24 are driven by a common piston-rod 27 from an electric motor 32 via a crank 30 and link 28. As a safety device a thermostat switch 48 de-energizes the motor 32 should the temperature within the heating coil 17 exceed a predetermined value. In a modified apparatus, the closure of a valve provided between the hose 18 and the nozzle 21 de-energizes the electric motor 32 by causing the opening of a fluid-actuated switch responsive to the pressure of liquid in the heating coil 17. In a further construction, pumps 8, 24, Fig. 3, draw the cleaning liquid from separate tanks 2, 2<SP>1</SP>, the inlet to the pump 24 being controlled by a valve 57, the operating coil of which is in series with a switch 61 controlled by the liquid pressure within the heating coil 17. The spray gun 20 has a rotatable nozzle head 64 so that either of two nozzles 65, 66 of different sizes may be used. When the larger nozzle 65 is used, the switch 61 remains closed and the valve 57 remains open so that both pumps 8, 24 are effective, but when the smaller nozzle 66 is used the switch 61 is opened to close the valve 57 and render the pump 24 ineffective. The spray gun having the rotary nozzle head 64 may be replaced by a gun having two independent nozzles of different sizes associated with a valve for diverting the flow from one to the other. A further valve may be provided between the hose 18 and the nose which when closed causes a fluid-pressure actuated switch to open to de-energize the motor 32. In another embodiment, the two pumps draw liquid from a common tank which may be supplied with either a strong solution of a cleaning agent or a weak solution through solenoid valves. The latter are controlled by a fluid-pressure actuated switch in such a manner that when the larger nozzle of the spray gun is used the weak solution is discharged thereby, and the strong solution is discharged when the smaller nozzle is used. The current supply to the apparatus may be controlled by a coin-operated timing device. Reference has been directed by the Comptroller to Specification 912,402.</p> |
