Automatic cleaning apparatus Patent #: 4159632
ApplicationNo. 05/963795 filed on 11/27/1978
US Classes:417/12, Having timer or delay means134/103.2, Fluid spraying means134/57R, With electric control137/392, Electrical characteristic sensing137/93By optical or chemical property
ExaminersPrimary: Freeh, William L.
Attorney, Agent or Firm
International ClassesA47L 15/44 (20060101)
A47L 15/42 (20060101)
AbstractA commercial-type automatic dishwasher includes a motor-driven circulating pump for recirculating a washing solution, a motor-driven detergent supply pump for adding detergent to the washing solution, and a control system, including control means for operating the circulating pump for a wash cycle of predetermined length, and detergent supply pump control means responsive to the pH level of the washing solution for operating the detergent supply pump as required during the wash cycle to maintain a desired water/detergent ratio. The detergent supply pump control means also includes an adjustable automatic timer which is set for a time interval less than the time of the wash cycle (but long enough to ensure that sufficient detergent can normally be supplied for the length of the wash cycle) which operates in response to a low pH level still existing at the end of the said time interval (indicative of loss of detergent supply) to turn off the detergent supply pump and actuate a warning device which alerts the machine operator to the faulty condition.
Field of SearchBy optical or chemical property