Water flow control system

• US 5,362,026 A
• Filed: 03/31/1994
• Issued: 11/08/1994
• Est. Priority Date: 06/15/1992
• Status: Expired due to Fees

• Current Assignee: Toto Limited
• Original Assignee: Toto Limited
• Inventors: Kobayashi, Hiroshi, Muroya, Yukihiro, Hayashi, Ryosuke, Inokuchi, Shoji
• Primary Examiner(s): Hepperle, Stephen M.
• Application Number:
  US08/220,624
• Time in Patent Office: 222 Days
• Field of Search: 137/613, 137/614.19, 137/505.13, 251/30.02, 251/30.05, 4/623
• US Class Current: 251/30.02
• CPC Class Codes: E03D 3/04 with piston valve and pressure chamber for retarding the valve-closing movement
• CPC Class Codes: E03D 5/10 operated electrically E03D5/01, E03D5/12 take precedence, e.g. by a photo-cell; also combined with devices for opening or closing shutters in the bowl outlet and/or with devices for raising/or lowering seat and cover and/or for swiveling the bowl
• CPC Class Codes: F16K 31/406 acting on a piston
• CPC Class Codes: Y10S 4/03 Electric flushing
• CPC Class Codes: Y10T 137/7796 Senses inlet pressure
• CPC Class Codes: Y10T 137/87917 Flow path with serial valves and/or closures
• CPC Class Codes: Y10T 137/88046 Biased valve with external operator

Abstract

A battery-operated flushing system (10) comprises a flushing valve (34) of the pilot-operated self-closing type having a pressure chamber (46) connected to a pilot conduit (52) controlled by a solenoid valve (50) of the non-latching type. A pressure control valve (48) is disposed between the pressure chamber (46) and the solenoid valve (50) for limiting the static water pressure applied to the solenoid valve (50) when the solenoid valve is closed. The provision for the pressure control valve (48) enables considerable reduction in the power consumption required to lift a solenoid valve plunger against the action of the static hydraulic pressure. Once the plunger is lifted, the non-latching type solenoid valve is energized with a reduced electric current sufficient to hold the valve in its open position. In total, energy consumption per cycle of operation is reduced. Use of the non-latching type solenoid valve permits to avoid malfunction inherently involved in the solenoid valves of the latching type. Various other embodiments are also disclosed.

Claims

1. A water flow control system comprising:

(A) a conduit for water having an inlet and an outlet, said inlet being adapted to be connected to a source of water under a primary water pressure;

(B) a solenoid valve of a non-latching type disposed in said conduit to control flow of water through said conduit;

(C) a pressure control valve disposed in said conduit upstream of said solenoid valve for reducing the primary pressure and for delivering to said solenoid valve a flow of water under a secondary pressure having a predetermined pressure level generally lower than the primary pressure at said inlet, said control valve comprising;

a housing defining a water passage therethrough;

a valve seat provided in said housing across said passage;

a movable closure member disposed in said housing downstream of said valve seat and cooperating with said valve seat to control flow of water through said passage;

...

a pressure receptive member disposed in said housing upstream of said valve seat for receiving and responding to the primary pressure at said inlet, said pressure receptive member being coupled to said closure member; and

spring means for biasing said closure member away from said valve seat;

means for adjustably varying the spring force of said spring means;

said closure member and said pressure receptive member being arranged so as to be subjected to the primary pressure in opposite directions so that the hydraulic forces acting thereon due to the primary pressure are substantially counterbalanced;

said closure member being responsive to the secondary pressure so as to be biased toward said valve seat;

said predetermined pressure level being determined in accordance with the spring force said spring means; and

(D) electric control means for controlling said solenoid valve, said electric control means being operable to energize said solenoid valve with an electric current having a first intensity when the opening movement of said solenoid valve is to be initiated and being operable to energize said solenoid valve with an electric current having a second intensity lower than said first intensity when said solenoid valve is to be maintained in its open state.

2. A battery-operated water flow control system comprising:

a pilot-operated self-closing valve having a water inlet adapted to be connected to a source of water under pressure and a water outlet, said valve having a pilot-operated pressure chamber for initiating the opening movement thereof and for retarding the closing movement thereof;

a pilot passage connected to said pressure chamber for releasing water pressure from said pressure chamber;

a battery-operated solenoid valve of the non-latching type disposed in said pilot passage to control release of pressure through said passage;

pressure control means disposed in said pilot passage between said pressure chamber and said solenoid valve for limiting the static water pressure applied from said pressure chamber to said solenoid valve when the solenoid valve is closed to a predetermined pressure level generally lower than the pressure at said water inlet; and

,

electric control means for controlling said solenoid valve, said electric control means being operable to energize said solenoid valve with an electric current having a first intensity when the opening movement of said solenoid valve is to be initiated and being operable to energize said solenoid valve with an electric current having a second intensity lower than said first intensity when said solenoid valve is maintained in its open state.

3. A flushing system comprising:

a flushing valve having a water inlet adapted to be connected to a source of water under pressure and a water outlet, said flushing valve being of the pilot-operated self-closing type having a pilot-operated pressure chamber for initiating the opening movement thereof and for retarding the closing movement thereof;

a pilot passage connected to said pressure chamber for releasing water pressure from said pressure chamber;

a solenoid valve of the non-latching type disposed in said pilot passage to control release of pressure through said passage;

pressure control means disposed in said pilot passage between said pressure chamber and said solenoid valve for limiting the static water pressure applied from said pressure chamber to said solenoid valve when the solenoid valve is closed to a predetermined pressure level generally lower than the pressure at said water inlet; and

,

electric control means for controlling said solenoid valve, said electric control means being operable to energize said solenoid valve with an electric current having a first intensity when the opening movement of said solenoid valve is to be initiated and being operable to energize said solenoid valve with an electric current having a second intensity lower than said first intensity when said solenoid valve is maintained in its open state.

4. A flushing system according to claim 3, wherein, for automatic flushing, said system further comprises sensing means for detecting the use of a toilet or urinal with which said flushing system is associated, said electric control means being responsive to said sensing means to energize said solenoid valve upon termination of the use of said toilet or urinal to deliver thereto a predetermined quantity of flushing water.

5. A flushing system according to claim 3, wherein said system further comprises pressure detection means for monitoring the static water pressure applied from said pressure chamber to said solenoid valve when the solenoid valve is closed, said electric control means being responsive to said pressure detection means to energize said solenoid valve for a predetermined period of time whenever said static pressure exceeds said predetermined pressure level thereby to reset the static pressure.

6. A flushing system according to claim 3, wherein said electric control means is operable to periodically energize said solenoid valve for a predetermined period of time in order to periodically reset the static pressure applied from said pressure chamber to said solenoid valve.

7. A flushing system according to claim 3, wherein said pressure control means includes:

a housing defining a water passage therethrough;

a valve seat provided in said housing across said passage;

a movable closure member disposed in said housing downstream of said valve seat and cooperating with said valve seat to control flow of water through said passage;

a pressure receptive member disposed in said housing upstream of said valve seat for receiving and responding to the pressure from said pressure chamber, said pressure receptive member being coupled to said closure member; and

,

spring means for biasing said closure member away from said valve seat;

said closure member and said pressure receptive member being arranged so as to be subjected to a primary pressure from said pressure chamber in opposite directions so that the hydraulic forces acting thereon due to said primary pressure are substantially counterbalanced;

said closure member being responsive to a secondary pressure downstream of said valve seat so as to be biased toward said valve seat;

said predetermined pressure level being determined in accordance with the spring force of said spring means.