Injection device of chemical fluids for improvements of the ground

An injection device for injecting a mixture of two fluids, fluid-A and fluid-B, into the ground for hardening the ground, said injection device comprising:

• a hollow outer pipe for injecting the fluid-A therethrough, said hollow outer pipe having an inwardly stepped portion on the inside wall for defining an upper greater diameter space and a lower lesser diameter space within the hollow interior thereof said hollow outer pipe having means for sealing closed the lower end thereof and said hollow outer pipe further having an annularly extending recessed portion on the outer surface thereof;
• a hollow inner pipe coaxially positioned within said hollow outer pipe within said upper greater diameter space, said hollow inner pipe sealingly connected at the lower end thereof to the inside wall of said hollow outer pipe at said inwardly stepped portion wherein the hollow interior of said hollow inner pipe communicates with said lower lesser diameter space for injecting fluid-B through said hollow inner pipe into said lower lesser diameter space;
• and
• resilient seal means located in said angularly extending recessed portion, said hollow outer pipe having first port means for connecting said upper greater diameter space with the exterior at said annularly extending recessed portion for allowing fluid-A to flow therethrough and second port means for connecting said lower lesser diameter space with the exterior at said annularly extending recessed portion for allowing fluid-B to flow therethrough, said resilient seal means for sealing said first and second port means closed when fluid-A and fluid-B are not being injected through said injection device and for defining a mixing chamber for mixing fluid-A and fluid-B and allowing the mixture to flow into the ground by expanding radially away from said annularly extending recessed portion.