Apparatus for dispensing a mixture of mutually reactive liquids

In apparatus for dispensing a mixture of mutually reactive liquids, comprising a gun head having a bore opening therethrough to define a cylindrical mixing chamber, means to deliver mutually reactive liquids along separate paths through said head and into said bore to mix in said bore and be dispensed through one end of said bore, a cylindrical valving rod reciprocable in the bore between a forward position in which the valving rod seals the liquid delivery means from each other and occupies the mixing chamber, and a rearward position in which the valving rod opens the mixing chamber and permits the flow of said liquids into the mixing chamber, the rod sliding in sealing relationship with the side walls of the mixing chamber in all positions of the rod in the mixing chamber;

• the improvement comprising means to feed one of said liquids along the outer surface of the valving rod in said retracted position of the valving rod and along most of the length of the valving rod which was disposed in the mixing chamber in said forward position of the valving rod, the forward end of the valving rod being disposed in said bore and isolating the mixing chamber from said means to feed one of said liquids in said retracted position of the valving rod, said separate path of said one liquid bypassing the forward end of the retracted valving rod so that said one liquid leaves the outer surface of the valving rod rearwardly of said forward end thereof and enters the mixing chamber forwardly of said forward end of the valving rod in said retracted position of the valving rod.