Fire extinguishing apparatus

Claim 1

A portable fire extinguishing assembly in combination: a selfpropelled fire extinguishing pumper-type vehicle which is utilized to assist firemen in extinguishing a fire; a first fluid conduit means communicating with and having one end connected to pressurized fire extinguishing fluid means and the other end of said fluid conduit connected to and communicating with a fluid conduit nozzle which directs the flow of the extinguishing fluid therethrough, said pressurized fluid means including pump means carried by and mounted on the pumper-type vehicle; said pump means having a discharge opening interconnected to said first fluid conduit means and a suction opening adapted to be operatively connected through a second fluid conduit means to a source of fire extinguishing fluid; a fire extinguishing pitottype fluid flow measuring and indicating means, for eliminating the need for the pump operator to mentally calculate all head loss due to friction between the fire extinguishing fluid and the side-walls of the first fluid conduit means and the difference in elevation between the discharge of the pump means and the fluid discharge nozzle, operatively connected to and communicates with the interior of the first fluid conduit means and including means for simultaneously measuring the static head and the velocity head of the fluid flowing through said first conduit means, said velocity head being taken at substantially the center of said first fluid conduit means, and means for comparing the static head with the velocity head to obtain a resultant pressure signal, said indicating means responsive to said signal for visually indicating the flow rate in units of volume with respect to time the quantity of fire extinguishing fluid flowing through the conduit means, thereby eliminating the need for firemen to calculate the head loss in the system; and the fluid flow measuring and indicating means includes a pivotal element which pivots about a point, one end of said element cooperates with means for visually indicating the quantity of fluid in units of volume with respect to time and the opposite end has a magnet secured thereto, another magnet is disposed on a piston member which moves in at least one direction in response to sensing a pressure difference between the static head and the velocity head of the fire extinguishing fluid flow, and at least one magnet pole of the magnet carried by the opposite end of the pivotal element is disposed in a substantially aligned and opposed relationship with at least one magnet pole of like polarity on the another magnet carried by the piston member for exerting a repelling force therebetween.