Abstract: A nozzle is used to mix two or more flowable reaction components which nozzle has a force controlled injection needle (7) and a force controlled needle casing (12) guided in a guiding bore (12). One component emerges centrally into an outlet channel (3) while the opening (25,26) of at least one further supply pipe (23,24) lies in the area of a sealing surface (4) which limits one side of the guide bore (2) and which forms a tight fit (18) with an outer sealing surface (17) thereof when the needle casing (12) is in a closed position.

Abstract: A process and a mixing head for the production of a reaction mixture comprising at least two reaction components, with a high degree of mixing. By this process, reaction components are introduced, at a high pressure into one end of the mixing chamber of the mixing head, these components being deflected by the front of the discharge piston which forms the opposite end of the chamber, a counterflow forming intensive turbulences on the wall of the mixing chamber and on the boundary surface with the incoming flow before this counterflow exits the mixing chamber at the same end through which it entered the chamber, substantially as a radially-directed, laminar flow.

Abstract: The present invention relates to an apparatus for the production of a flowable reaction mixture of at least two flowable components which mixture forms a foam or solid material, comprising:(a) storage means for said components;(b) supply lines leading from the storage means via metering pumps to a mixing head;(c) said mixing head having a mixing chamber;(d) injection openings connected to said supply lines and opening into said mixing chamber;(e) said mixing chamber having an outlet opening downstream of said injection openings;(f) said outlet opening having an elastic outlet tube whose throughflow cross section may be varied connected thereto; said apparatus further characterized in that:(g) the outlet tube has at least one means associated therewith for deflecting said outlet tube;(h) an ejection piston is associated with said outlet tube, which piston is capable of filling the outlet tube; the contour of the inside wall of said outlet tube corresponding to the external contour of said ejection piston.

Abstract: Hydraulically coupled injection nozzles (5,28) and return nozzles (15,38) are used in an apparatus for producing a reaction mixture of fluid components forming foam or a solid material. These nozzles (5,15,28,38) comprise control pins (11,20,34,43) which are designed to be inserted into the openings (6,17,29,40) of the nozzles (5,15,28,38). The ratio between the distances which the control pins (11,20,34,43) travel outside and inside the orifices (6,17,29,40) is adjusted in such a way that, when the nozzles (5,15,28,38) are switched from "mixing" to "circulation" or vice versa, there is a time interval during which all the nozzles (5,15,28,38) are closed.