Dish machine monitoring of time, temperature, alkalinity, and pressure parameters

• US 3,896,827 A
• Filed: 08/31/1973
• Issued: 07/29/1975
• Est. Priority Date: 08/31/1973
• Status: Expired due to Term

• Current Assignee: Norman R. Robinson
• Original Assignee: Norman R. Robinson
• Inventors: Robinson, Norman R.
• Primary Examiner(s): Bashore, S. Leon
• Assistant Examiner(s): Fisher, Richard V.
• Application Number:
  US05/393,345
• Time in Patent Office: 697 Days
• Field of Search: 134/18,10,25A,25R,29,30,32,57D,58D,72,56D,48 417/474,477 58/145R
• US Class Current: 134/10
• CPC Class Codes: A47L 15/0044 Operation time reduction
• CPC Class Codes: A47L 15/0049 Detection or prevention of malfunction, including accident prevention arrangements to prevent clogging of filters A47L15/4208; safety arrangements for preventing water damage A47L15/421
• CPC Class Codes: A47L 15/0055 Metering or indication of used products, e.g. type or quantity of detergent, rinse aid or salt; for measuring or controlling the product concentration
• CPC Class Codes: A47L 15/241 the dishes moving in a horizontal plane
• CPC Class Codes: A47L 15/4427 entrained in the water supply line by a pressure drop, e.g. resulting from a Venturi throat
• CPC Class Codes: A47L 2401/11 Water hardness, acidity or basicity
• CPC Class Codes: A47L 2401/12 Water temperature
• CPC Class Codes: A47L 2401/14 Water pressure or flow rate
• CPC Class Codes: A47L 2501/07 Consumable products, e.g. detergent, rinse aids or salt
• CPC Class Codes: A47L 2501/26 Indication or alarm to the controlling device or to the user

Abstract

A dishwasher control system for automatically recording the duration of machine operation to determine cost of supplies, service and use. Machine operation is commenced by sensing the pressure of dishes and stopped automatically at the end of the cycle. During operation, the wash water is continuously sampled and checked for low temperature, low detergent and low pressure.

Claims

1. THE TEMPERATURE AND SIGNALLING WHEN A TEMPERATURE IS DETERMINED TO BE BELOW A PREDETERMINED VALUE,

2. time measuring means to determine the duration of operation of the dish washing machine,

3. PRESSURE AND SIGNALLING WHEN PRESSURE FALLS BELOW A PREDETERMINED VALUE.

4. a first pressure responsive means in said fill line for determining the presence of water in the fill line,

5. A method as in claim 1 wherein dishwashing additives are automatically blended into the sample of circulating dish washing liquid as needed before the sample is returned to the main flow of circulating liquid.

6. peristaltic pump means for blending additives into a line communicating with said recirculating water to restore conductivity above a predetermined level, and

7. A method as in claim 1 wherein dish machine operation is prevented except when wash water heaters are in operation.

8. In a control system for a dishwashing machine, at least one water spray station, a conveyor for dishes, and a recirculating pump to recirculate wash water, the improvement comprising

9. A system as in claim 8 including measuring means responsive to the means for energizing the control system and to said switch means, whereby said measuring means measures the duration of operation of the dishwashing machine.

10. A system as in claim 8 wherein the dishwashing machine has a fill line, the improvement comprising pressure sensitive means in said fill line to detect the flow of water in said line and signal means to alert the machine operator to the flow of water in the fill line.

11. A system as in claim 8 including multiple sources for dish washing additives and flexible tubes for passing additives from each of the multiple sources to the dishwashing machine, the improvement comprising pump means engaging said flexible tubes to pump the additives, said pump means having a rotating driven shaft, a wheel rotatably mounted on said shaft, two or more rods extending parallel to said shaft from the periphery of said wheel, each of said flexible tubes passing over said rods, and tension means for placing the length of flexible tube from each source passing over said rods under tension, whereby the contents within the tubes are pumped as the rods peristaltically stretch said tubes upon rotation of the wheel about the shaft.

12. A system as in claim 11 wherein the tubes downstream of said pump means enter a mixing manifold comprising an inlet chamber, a venturi throat and an exit chamber communicating to the dishwashing machine, whereby additives flowing from said pump means are accelerated through the venturi throat.

13. In a control system for a dish washing machine having a fill line, a loading station, at least one water spray station, a water heater, a dish conveyor, a recirculating pump and recirculating water, the improvement comprising