Patent ID: 7942613

Claim:
An injection pistol for injecting a sealing product formed by a mixture of a first solution and a second solutions through an injection hole, comprising: a tubular injection system which is supplied with said first and second solutions under pressure, wherein the tubular injection system comprises: a first transfer conduit to convey the first solution, said first transfer conduit comprising a first tube having a proximal end, a distal end, and a circular cross-section; a second tube having a proximal end, a distal end, and a circular cross-section, said second tube arranged concentrically around the first tube; a second transfer conduit to convey the second solution, said second transfer conduit comprising an annular cross-section defined by an annular space between the first tube and the second tube; a protective tube having a proximal end and a distal end, said protective tube surrounding the first tube and the second tube, said first tube and said second tube adapted to be displaced relative to the protective tube; an expansible sleeve having elastic radial deformation, said expansible sleeve being attached to the distal end of the protective tube; and a frusto-conical part attached to the distal end of the second tube, the distal ends of the first tube and the second tube passing through the frusto-conical part; and a dual action actuator adapted to control the displacement of the first and second tubes relative to the protective tube between a first rest position in which the expansible sleeve and the frusto-conical part can be introduced into the injection hole, and an expanded position in which the frusto-conical part is retracted proximally to expand the expansible sleeve against an inner wall of the injection hole for delivery of the first and second solutions to the injection hole without any backflow; wherein a compressed air supply delivers compressed air to a space formed between the protective tube and the second tube up to the frusto-conical part for cleaning the frusto-conical part.