Automatic water shutoff system

Abstract

An automatic water shutoff system for filling water tanks on concrete mixer trucks, including a nozzle assembly attached to a water hose. The nozzle assembly includes a first elongated tube surrounded by a second shorter tube. A flange closes the proximal end of the second tube and forms an air chamber between the first and second tubes. The end of the first tube closest to the flange forms a water inlet nipple. An air pressure sensing tap is formed by a small tube passing through the flange. One end of the tap communicates with the air chamber and a second end of the tap is attachable to an air pressure sensing tube, operatively coupled to a pressure switch. When pressure in the air chamber reaches a predetermined, water tank full level, the pressure switch causes the pump or valve to turn off the flow of water into the tank.

We claim:  
     
         1 . A automatic water shutoff system for preventing the overflow of containers comprising: 
 a nozzle assembly adapted for connection to a liquid supply hose, said nozzle assembly including chamber means for forming a column of air which is pressurized by liquid in the container above a predetermined level;    an electrically actuated liquid supply means for controlling the supply of liquid to the liquid supply hose;    control box means for electrically actuating the liquid supply means; and    means responsive to the pressure of the air within the chamber means, the pressure responsive means being operatively coupled to the nozzle assembly and the control box means for actuating the liquid supply means to shut off the supply of liquid to the hose when liquid within the container is at a full level.    
     
     
         2 . The automatic water shut-off system according to  claim 1 , wherein said nozzle assembly comprises: 
 a stop flange secured around a first water supply tube adjacent one end thereof to form a water supply nozzle on one side of said flange and a water inlet nipple on the other side of said flange;    said chamber means includes a second tube of larger diameter and smaller length surrounding said nozzle and secured to said stop flange so as to form an air chamber containing said column of air; and    a third tube is secured within an aperture passing through said stop flange for communicating with said column of air within said chamber, wherein said third tube forms an air pressure sensing tap.    
     
     
         3 . The automatic water shut-off system according to  claim 1 , wherein said electrically actuated liquid supply means comprises a water pump assembly.  
     
     
         4 . The automatic water shut-off system according to  claim 1 , wherein said electrically actuated liquid supply means comprises an electrically actuated valve assembly.  
     
     
         5 . The automatic water shut-off system according to  claim 1 , wherein said pressure responsive means is in the form of a pressure responsive switch assembly.  
     
     
         6 . The automatic water shut-off system according to  claim 2 , wherein said pressure responsive means is in the form of a pressure responsive switch assembly.  
     
     
         7 . The automatic water shut-off system according to  claim 3 , wherein said pressure responsive means includes a pressure responsive switch assembly operatively connected to a circuit in said control box means for turning said water pump assembly on and off.  
     
     
         8 . The automatic water shut-off system according to  claim 4 , wherein said pressure responsive means includes a pressure responsive switch assembly operatively connected to a circuit in the control box means for opening and closing said valve assembly.  
     
     
         9 . The automatic water shut-off system according to  claim 2 , wherein said electrically actuated liquid supply means comprises a water pump assembly.  
     
     
         10 . The automatic water shut-off system according to  claim 2 , wherein said electrically actuated liquid supply means comprises an electrically actuated valve assembly.  
     
     
         11 . The automatic water shut-off system according to  claim 9 , wherein said pressure responsive means includes a pressure responsive switch assembly operatively connected to a circuit in said control box means for turning said water pump assembly on and off.  
     
     
         12 . The automatic water shut-off system according to  claim 10 , wherein said pressure responsive means includes a pressure responsive switch assembly operatively connected to a circuit in the control box means for opening and closing said valve assembly.  
     
     
         13 . An automatic water shut-off system for preventing the overfilling of containers comprising: 
 a nozzle assembly adapted for connection to a liquid supply hose, said nozzle assembly including chamber means for forming a column of air which is pressurized by liquid in the container above a predetermined level; and    means responsive to the pressure of the air within the chamber means, the pressure responsive means being operatively coupled to the nozzle assembly.    
     
     
         14 . The automatic water shut-off system according to  claim 13 , wherein said nozzle assembly comprises: 
 a stop flange secured around a first water supply tube adjacent one end thereof to form a water supply nozzle on one side of said flange and a water inlet nipple on the other side of said flange;    said chamber means includes a second tube of larger diameter and smaller length surrounding said nozzle and secured to said stop flange so as to form an air chamber containing said column of air; and    a third tube is secured within an aperture passing through said stop flange for communicating with said column of air within said chamber, wherein said third tube forms an air pressure sensing tap.    
     
     
         15 . The automatic water shut-off system according to  claim 13 , wherein said pressure responsive means is in the form of a pressure responsive switch assembly.  
     
     
         16 . The automatic water shut-off system according to  claim 14 , wherein said pressure responsive means is in the form of a pressure responsive switch assembly.  
     
     
         17 . The automatic water shut-off system according to claim including a flexible tube operatively connected to said pressure sensing tap.  
     
     
         18 . The automatic water shut-off system according to  claim 16 , including a flexible tube operatively connected to said pressure sensing tap and said pressure responsive switch assembly.  
     
     
         19 . A nozzle assembly adapted for connection to a liquid supply hose, said nozzle assembly including chamber means for forming a column of air which may be pressurized by a rising liquid level in a container into which the nozzle assembly is placed, wherein said chamber means includes a pressure sensing tap.  
     
     
         20 . A nozzle assembly according to  claim 19 , wherein said nozzle assembly comprises: 
 a stop flange secured around a first water supply tube adjacent one end thereof to form a water supply nozzle on one side of said flange and a water inlet nipple on the other side of said flange;    said chamber means includes a second tube of larger diameter and smaller length surrounding said water supply nozzle and secured to said stop flange so as to form an air chamber containing said column of air; and    a third tube is secured within an aperture passing through said stop flange for communicating with said column of air within said chamber, wherein said third tube forms said air pressure sensing tap.