Apparatus for ejecting a mixture of a plurality of liquids

Abstract

Apparatus for ejecting a mixture of liquids, e.g. urethane foam, comprises a cylindrical chamber into which the liquids are separately introduced under pressure and mixed and ejected from the open end of the chamber. A reciprocable plunger alternately exposes the inlets in its rear portion and seals the inlets from each other and purges the chamber in its forward position. The inlets are axially spaced apart and separated from each other by a throat that has interference fit with the plunger in the forward position of the plunger, the plunger having for this purpose an elastic deformable surface.

Having described our invention, we claim: 
     
       1. Apparatus for ejecting a mixture of a plurality of liquids, comprising a mixing chamber having an outlet opening and a plurality of spaced inlets which are spaced different distances from said outlet opening, means for separately introducing different liquids into the chamber through said inlets, a plunger reciprocable in the chamber between forward and rear positions, the differently spaced inlets communicating with the chamber and with each other in said rear position of the plunger, and means sealing against the plunger in the forward position of the plunger to seal said inlets from each other, the forward end of the plunger being forward of all said inlets in said forward position of the plunger and being rearward of all said inlets in said rear position of the plunger.Iadd., the surface of one of said plunger and sealing means being an elastic deformable material, said sealing means comprising an annular throat in which said plunger reciprocates with an interference fit, said plunger being in sealing contact with said throat in said forward position and exposing all said inlets to each other in said rear position, said forward end of said plunger being disposed on opposite sides of said throat in said forward and rear positions, said inlets being disposed on opposite sides of said throat. .Iaddend.  .[.2. Apparatus as claimed in claim 1, in which the surface of one of said plunger and sealing means is an elastic 
     
     
        deformable material..]. 3. Apparatus as claimed in claim .[.2.]. .Iadd.1.Iaddend., in which the surface of said plunger is an elastic deformable material. .[.4. Apparatus as claimed in claim 1, said sealing means comprising an annular throat in which said plunger reciprocates with an interference, said plunger being in sealing contact with said throat in said forward position and exposing all said inlets to each other in said rear position, said forward end of said plunger being disposed on opposite sides of said throat in said forward and rear positions, said inlets being 
     
     
        disposed on opposite sides of said throat..]. 5. Apparatus as claimed in claim .[.4.]. .Iadd.1.Iaddend., said inlets extending through slots formed in the ends of separable members that abut said throat on opposite sides 
     
     
        of said throat, said throat closing one side of each of said slots. 6. Apparatus as claimed in claim 5, said opposite sides of said throat 
     
     
        converging radially inwardly. 7. Apparatus as claimed in claim 6, said 
     
     
        slots on opposite sides of said throat converging radially inwardly. 8. Apparatus for ejecting a mixture of a plurality of liquids, comprising a mixing chamber having an outlet opening and a plurality of spaced inlets which are spaced different distances from said outlet opening, means for separately introducing different liquids into the chamber through said inlets, a plunger reciprocable in the chamber between forward and rear positions, the differently spaced inlets communicating with the chamber and with each other in said rear position of the plunger, and means sealing against the plunger in the forward position of the plunger to seal said inlets from each other, said plunger adjacent said sealing means comprising a sleeve of elastic deformable material on a metal rod.Iadd., said rod having grooves on its outer surface which are only partially filled by the material of said sleeve. .Iaddend. .[.9. Apparatus as claimed in claim 8, said rod having grooves on its outer surface which are 
     
     
        only partially filled by the material of said sleeve..]. 10. Apparatus for ejecting a mixture of a plurality of liquids, comprising a mixing chamber having an outlet opening and a plurality of spaced inlets which are spaced different distances from said outlet opening, means for separately introducing different liquids into the chamber through said inlets, a plunger reciprocable in the chamber between forward and rear positions, the differently spaced inlets communicating with the chamber and with each other in said rear position of the plunger, and means sealing against the plunger in the forward position of the plunger to seal said inlets from each other, said sealing means comprising an annular throat in which said plunger reciprocates with an interference fit, said plunger being in sealing contact with said throat in said forward position and exposing all said inlets to each other in said rear position, said forward end of said plunger being disposed on opposite sides of said throat in said forward and rear positions, said inlets being disposed on opposite sides of said throat, said inlets extending through slots formed in the ends of separable members that abut said throat on opposite sides of said throat, said throat closing one side of each of said slots, said separable member on the same side of said throat as said outlet opening being carried by a floating packing sleeve through which said plunger extends in said forward position. .[.11. Apparatus for ejecting a mixture of a plurality of liquids, comprising a mixing chamber having an outlet opening and a plurality of spaced inlets which are spaced different distances from said outlet opening, means for separately introducing different liquids into the chamber through said inlets, a plunger reciprocable in the chamber between forward and rear positions, the differently spaced inlets communicating with the chamber and with each other in said rear position of the plunger, and means sealing against the plunger in the forward position of the plunger to seal said inlets from each other, there being a plurality of said inlets for each said liquid, all the inlets for one said liquid being equally peripherally spaced about said chamber and being the same distance from said outlet opening..]. .[.12. Apparatus as claimed in claim 11, all said inlets for each said liquid being offset the same 
     
     
        distance and in the same direction from the axis of the chamber..]. 13. Apparatus for ejecting a mixture of a plurality of liquids, comprising a mixing chamber having an outlet opening and a plurality of spaced inlets which are spaced different distances from said outlet opening, means for separately introducing different liquids into the chamber through said inlets, a plunger reciprocable in the chamber between forward and rear positions, the differently spaced inlets communicating with the chamber and with each other in said rear position of the plunger, and means sealing against the plunger in the forward position of the plunger to seal said inlets from each other, said inlets farthest from said outlet opening being inclined forwardly and said inlets nearest said outlet opening being inclined rearwardly. .Iadd. 14. Apparatus as claimed in claim 1, said inlets being defined between said throat and separable members on opposite sides of said throat, the inside diameter of said separable members being greater than the inside diameter of said throat. .Iaddend. .Iadd. 15. Apparatus as claimed in claim 1, said plunger adjacent said sealing means comprising a sleeve of elastic deformable material on a rod, said rod having grooves on its outer surface which are only partially filled by the material of said sleeve. .Iaddend. .Iadd. 16. Apparatus as claimed in claim 10, said inlets farthest from said outlet opening being inclined forwardly and said inlets nearest said outlet opening being inclined rearwardly, said separable members both having conical surfaces in contact with said throat. .Iaddend. .Iadd. 17. Apparatus as claimed in claim 13, said sealing means comprising an annular throat in which said plunger reciprocates, said plunger being in sealing contact with said throat in said forward position and exposing all said inlets to each other in said rear position, said forward end of said plunger being disposed on opposite sides of said throat in said forward and rear positions, said inlets being disposed on opposite sides of said throat, said inlets being defined between separable members that abut said throat on opposite sides of said throat, said throat closing one side of each of said inlets, said separable members both having conical surfaces in contact with said throat. .Iaddend. .Iadd. 18. Apparatus as claimed in claim 17, in which said inlets are in the form of slots formed in said conical surfaces. .Iaddend. .Iadd. 19. Apparatus for ejecting a mixture of a plurality of liquids, comprising a mixing chamber having an outlet opening and a plurality of spaced inlets which are spaced different distances from said outlet opening, means for separately introducing different liquids into the chamber through said inlets, a plunger reciprocable in the chamber between forward and rear positions, the differently spaced inlets communicating with the chamber and with each other in said rear position of the plunger, and means sealing against the plunger in the forward position of the plunger to seal said inlets from each other, said sealing means comprising an annular throat in which said plunger reciprocates, said plunger being in sealing contact with said throat in said forward position and exposing all said inlets to each other in said rear position, said forward end of said plunger being disposed on opposite sides of said throat in said forward and rear positions, said inlets being disposed on opposite sides of said throat and being defined between said throat and the ends of separable members that abut said throat on opposite sides of said throat, said throat closing one side of each of said inlets, said separable member on the same side of said throat as said outlet opening being carried by a packing sleeve of elastic deformable material through which said plunger extends in said forward position. .Iaddend. .Iadd. 20. Apparatus as claimed in claim 19, said inlets nearest said outlet opening being inclined rearwardly and the surface of said separable member on the same side of said throat as said outlet opening being conical and being in contact with a conical surface of said throat. .Iaddend. .Iadd. 21. Apparatus as claimed in claim 20, in which the inside diameter of said separable member on the same side of said throat as said outlet opening is greater than the inside diameter of said throat. .Iaddend. .Iadd. 22. Apparatus for ejecting a mixture of a plurality of liquids, comprising a mixing chamber having an outlet opening and a plurality of spaced inlets which are spaced different distances from said outlet opening, means for separately introducing different liquids into the chamber through said inlets, a plunger reciprocable in the chamber between forward and rear positions, the differently spaced inlets communicating with the chamber and with each other in said rear position of the plunger, and means sealing against the plunger in the forward position of the plunger to seal said inlets from each other, said sealing means comprising an annular throat in which said plunger reciprocates, said plunger being in sealing contact with said throat in said forward position and exposing all said inlets to each other in said rear position, said forward end of said plunger being disposed on opposite sides of said throat in said forward and rear positions, said inlets being disposed on opposite sides of said throat, the surface of said plunger in and adjacent said throat being an elastic deformable material, the inside diameter of said throat being less than the normal outer diameter of said surface of elastic deformable material. .Iaddend. .Iadd. 23. Apparatus as claimed in claim 22, said plunger adjacent said throat comprising a sleeve of said elastic deformable material on a rod, said rod having grooves on its outer surface which are only partially filled by the material of said sleeve. .Iaddend.