Heat exchanger

Heat exchanger (1) having at least one tube connection and at least one heat-exchanger tube (11) which is held, at one end, in a liquid-tight or gas-tight manner in a plastic tube base (3), the tube base (3) exhibiting for each tube connection (6) an opening (7) for passage of heat-exchanger fluid from the tube (11) into a junction box (2) or in a reverse direction and the tube base (3) exhibiting, in an area of the opening (7), for each tube connection a sleeve-shaped connecting socket (8), in which there is disposed an annular groove (9), extending coaxially to the opening (7) and open in a direction of the heat-exchanger tube (11), by which annular groove an inner ring (14) and an outer ring (15) are formed and into which annular groove the end (11*) of the heat-exchanger tube (11) is pressed, characterized in that a section (15*) of the outer ring (15) which is adjacent to a heat-exchanger block (10) is of longer construction than a corresponding section (14*) of the inner ring (14), characterized in that the outer ring (15) is provided, on its section (15*), with an arc-shaped widening (16), characterized in that an end point (x) of the widening (16) and an end point (b) of a curvature (17) of the inner ring exhibit, in relation to a longitudinal axis (18) of the tube connection (6), a radial distance (s1) amounting to two to three times a tubular wall thickness (s0) of the heat-exchanger tube (11).

Heat exchanger (1) having at least one tube connection and at least one heat-exchanger tube (11) which is held, at one end, in a liquid-tight or gas-tight manner in a plastic tube base (3), the tube base (3) exhibiting for each tube connection (6) an opening (7) for passage of heat-exchanger fluid form the tube (11) into a junction box (2) or in a reverse direction and the tube base (3) exhibiting, in an area of the opening (7), for each tube connection a sleeve-shaped connecting socket (8), in which there is disposed an annular groove (9), extending coaxially to the opening (7) and open in a direction of the heat-exchanger tube (11), by which annular groove an inner ring (14) and an outer ring (15) are formed and into which annular groove the end (11*) of the heat-exchanger tube (11) is pressed, characterized in that a section (15*) of the outer ring (15) which is adjacent to a heat-exchanger block (10) is of longer construction than a corresponding section (14*) of the inner ring (14), characterized in that the inner ring (14), at the open end of the annular groove (9), possesses a curvature (17), so that the annular groove is thereby widened, characterized in that an end point (x) of the widening and an end point (b) of the curvature of the inner ring exhibit, in relation to a longitudinal axis of the tube connection, a radial distance (s1) amounting to two to three times a tubular wall thickness (s0) of the heat-exchanger tube.