FOAMING SYSTEM AND IMPROVED FOAMING DEVICE

• US 3,823,727 A
• Filed: 06/26/1972
• Issued: 07/16/1974
• Est. Priority Date: 06/24/1971
• Status: Expired due to Term

• Current Assignee: Arthur Francis Fry
• Original Assignee: Arthur Francis Fry
• Inventors: Fry, Arthur Francis
• Primary Examiner(s): Nilson, Robert G.
• Application Number:
  US05/266,041
• Time in Patent Office: 750 Days
• Field of Search: 137/7,88,114,170.2 134/102 169/14
• US Class Current: 137/88
• CPC Class Codes: C23G 3/00 Apparatus for cleaning or pickling metallic material with organic solvents C23G5/04
• CPC Class Codes: D21F 1/32 Washing wire-cloths or felts
• CPC Class Codes: Y10T 137/0352 Controlled by pressure
• CPC Class Codes: Y10T 137/2499 Mixture condition maintaining or sensing
• CPC Class Codes: Y10T 137/85954 Closed circulating system

Abstract

A foam cleaning system and a foam cleaner which is provided with a control actuated by build-up of static pressure in a foaming chamber to cut off air pressure to the chamber thus ensuring that during periods when foam is not being produced the pressure on the foamer hose is minimized. The foamer also has a facility whereby any tendency of leakage of liquid back into the air system is prevented and automatic purging takes place on the pressure drop in the foam chamber.

Claims

1. A foaming system comprising a foam chamber for receiving at least a foaming agent, a delivery line connected to said foam chamber for delivering the foam generated therein to a preselected location, air conduit means adapted to be connected between a source of pressurized air and to said foam chamber for supplying pressurized air to said foam chamber, said air conduit means comprising control means connected to said foam chamber and responsive to the pressure in said chamber rising above a predetermined value for stopping the flow of said pressurized air from the source to said foam chamber.

2. A foaming system as in claim 1, in which said control means comprises an air control valve having an air passage, and a pressure sensing line connected between said foam chamber and said control valve, said control valve having a valve member movable from a first position wherein said air passage is open to permit the flow of air therethrough to a second position when the pressure is said line exceeds said predetermined value wherein said air passage is closed to prevent the flow of said pressurized air therethrough.

3. A foaming system as claimed in claim 2 wherein the air control valve comprises a valve having a diaphragm therein, said sensing line being connected to one side of said diaphragm, and a source of air, at a predetermined pressure sufficient to maintain the valve open during delivery of said foam, being connected to the other side of the diaphragm.

4. A foaming system as claimed in claim 2 wherein the air control valve comprises a valve having a diaphragm therein, said sensing line being connected to one side of said diaphragm, and a spring exterting a force against the other side of the diaphragm, the pressure exerted by said spring being sufficient to maintain the valve open during delivery of said foam.

5. A foaming system as in claim 1, wherein said foam chamber is provided with an air inlet through which said pressurized air flows, said air conduit means further comprising a non-return valve connected to said air inlet, and a shut-off valve connected upstream of said non-return valve, said shut-off valve having valve means therein movable from a first position to permit pressurized air to flow through said valve to a second position in response to pressure in said chamber above said predetermined value for stopping the flow of pressurized air through said valve and for venting to the atmosphere liquid leaking past said non-return valve.

6. A foaming system as in claim 5, wherein said shut-off valve is connected between said source of pressurized air and said foam chamber, said control means comprising a valve movable from an open position to permit the flow of a fluid therethrough to a closed position in response to the pressure in said chamber above said predetermined value to prevent flow of the fluid therethrough, means interconnecting said control means valve and said shut-off valve whereby fluid from the control means valve operates said shut-off valve valve means to the first position and the lack of fluid flow from said control means valve permits movement of said shut-off valve valve means to the second position.

7. A foamer comprising an air source, a pressure regulator having an outlet with at least two branches, an air control valve connected to one of said branches, a shut-off valve and a non-return valve connected in series, said air control valve having an outlet connected to said shut-off valve, a foam chamber, said non-return valve having an outlet connected to said foam chamber, a source of pressurized air connected to said shut-off valve whereby when said shut-off valve is in the open position pressurized air flows through said shut-off valve to said foam chamber and when said shut-off valve is in the closed position pressurized air is prevented from flowing to said foam chamber, vent means in said shut-off valve operable when said valve is in the closed position to provide a path from said non-return valve to the atmosphere, inlet means connected to said foam chamber to permit entrance of a liquid, an outlet connected to said foam chamber to permit discharge of foam, said shut-off valve having valve means responsive to air flow from said air control valve for operating said shut-off valve to the valve open position, said air control valve being responsive to pressure in said foaming chamber above a predetermined level for preventing air flow from said shut-off valve, and line means connecting said foam chamber with said air control valve to permit said air control valve to sense the pressure in said foaming chamber.

8. A foam cleaning system comprising storage means for a liquid, a pump associated with said storing means to deliver the liquid under a predetermined pressure, a liquid main in the area to be served by the main system having at least one branch, a foamer including a foam chamber to which a mixture of at least water, an active chemical and a foaming agent can be supplied, a delivery line connected to said foam chamber for delivering the foam generated therein to a preselected location, air conduit means adapted to be connected between a source of pressurized air and to said foam chamber for supplying pressurized air to said foam cHamber, said air conduit means comprising control means connected to said foam chamber and responsive to the pressure in said chamber above a predetermined value for stopping the flow of said pressurized air from the source to said foam chamber.

9. A system as claimed in claim 8, wherein a plurality of branches are provided each adapted to be connected to a foamer.