HYDRAULIC CONTROL SYSTEM FOR A WASHING MACHINE

• US 3,646,948 A
• Filed: 09/14/1970
• Issued: 03/07/1972
• Est. Priority Date: 01/06/1969
• Status: Expired due to Term

• Current Assignee: Whirlpool Corporation
• Original Assignee: Stuart E. Athey
• Inventors: Athey, Stuart E.
• Primary Examiner(s): Bleutge, Robert L.
• Application Number:
  US05/072,039
• Time in Patent Office: 540 Days
• Field of Search: 134/56D,57D,57DL,58D,97,98,186 137/563
• US Class Current: 134/57.00D
• CPC Class Codes: A47L 15/4217 Fittings for water supply, e.g. valves or plumbing means to connect to cold or warm water lines, aquastops
• CPC Class Codes: A47L 15/4219 Water recirculation A47L15/0078 takes precedence
• CPC Class Codes: Y10T 137/85954 Closed circulating system

Abstract

A dishwashing machine has two solenoid actuated fill valves within a water supply line, and pressure tap between the solenoid valves is connected to a normally closed pressure actuated drain valve within a drain line to provide for controlling the drain valve in response to selective actuation of the fill valves. The fill valves are controlled by a timer according to a predetermined sequence, and the downstream fill valve is also actuated by a centrifugal switch responsive to operation of the motor for the recirculating means.

Claims

1. A dishwashing machine comprising a tank defining a chamber having rack means therein for receiving articles to be cleaned, a water supply line extending to said tank, first and second fill valves within said water supply line, said first fill valve being located upstream of said second fill valve relative to the flow of water within said supply line, means including a motor for circulating water within said chamber, means including a drain line for removing water from said chamber, a normally closed drain valve within said drain line, water pressure actuated means for operating said drain valve, means defining a water passageway connecting said pressure-actuated means to said water supply line between said first and second fill valves for controlling the operation of said drain valve in response to selected operation of said fill valves, timer means for actuating said motor and said fill valves according to a predetermined program, said drain valve being open when said first fill valve is open and said second fill valve is closed, said drain valve being closed when both said fill valves are either open or closed or when said first fill valve is closed and said second fill valve is open, and control means separate from said timer means for at least momentarily opening said second fill valve when said first fill valve is closed to assure a release of water pressure within said passageway when both said fill valves are closed.

2. A washing machine as defined in claim 1 wherein said latter control means comprises a centrifugally actuated switch operated by said motor.

3. A washing machine as defined in claim 2 wherein said switch is normally open when the shaft of said motor is stationary.

4. A washing machine as defined in claim 1 including a housing supporting both said fill valves and said water pressure actuated means.