Heat transfer medium connection assembly unit, especially for a heat exchanger arrangement of a vehicle heater

1. A heat transfer medium assembly unit for a heat exchanger arrangement of a vehicle heater, the heat transfer medium assembly unit comprising:

a housing part with at least one connecting branch receiving opening;

a plurality of flexible fixing elements are associated with the at least one connecting branch receiving opening, the plurality of flexible fixing elements being provided for fixing a connecting branch mounted in the at least one connecting branch receiving opening to the housing part for providing a connecting branch-housing part pre-assembled unit, wherein the plurality of flexible fixing elements are arranged at spaced locations from one another and are provided on an inner circumference of the at least one connecting branch receiving opening;

the at least one connecting branch receiving opening has a lateral connecting branch insertion opening allowing insertion of the connecting branch through the lateral connecting branch insertion opening into the at least one connecting branch receiving opening;

wherein at least one of the flexible fixing elements comprises a fixing tongue formed integrally with the housing part and protruding into the at least one connecting branch receiving opening; and

wherein at least one of (a) the at least one of the flexible fixing elements is provided in a first circumferential area of the at least one connecting branch receiving opening located opposite the lateral connecting branch insertion opening and (b) the at least one of the flexible fixing elements is provided in a second circumferential area adjoining the lateral connecting branch insertion opening with respect to a circumferential direction.

2. The heat transfer medium assembly unit in accordance with claim 1 , wherein the at least one connecting branch receiving opening has an inner circumferential contour adapted to an outer circumferential contour of the connecting branch, which is to be mounted therein.

3. The heat transfer medium assembly unit in accordance with claim 1 , wherein:

a first positive-locking meshing formation with internal teeth is provided associated with the at least one connecting branch receiving opening;

a second positive-locking meshing formation with external teeth is provided on the connecting branch to be received in the at least one connecting branch receiving opening locking

the connecting branch against rotation by a positive-locking meshing between the first positive-locking meshing formation and the second positive-locking meshing formation.

4. The heat transfer medium assembly unit in accordance with claim 3 , wherein the second positive-locking meshing formation is provided on a flange area of the connecting branch, said flange area protruding outwardly in a radial direction in relation to a longitudinal axis of the connecting branch.

5. The heat transfer medium assembly unit in accordance with claim 3 , wherein:

the at least one connecting branch receiving opening has a first opening length section for receiving a cylindrical section of the connecting branch to be mounted therein;

the at least one connecting branch receiving opening has a second opening length section providing the first positive-locking meshing formation for receiving a section of the connecting branch providing the second positive-locking meshing formation;

the at least one connecting branch receiving opening having a smaller internal dimension in the first length section than in the second length section.

6. A heat exchanger arrangement for a vehicle heater, the heat exchanger arrangement comprising:

a heat exchanger body providing a heat transfer medium flow space; and

at least one heat transfer medium assembly unit, the heat transfer medium assembly unit comprising:

a housing part with at least one connecting branch receiving opening;

a plurality of flexible fixing elements are associated with the at least one connecting branch receiving opening, the plurality of flexible fixing elements being provided for fixing a connecting branch mounted in the at least one connecting branch receiving opening to the housing part for providing a connecting branch-housing part pre-assembled unit, wherein the plurality of flexible fixing elements are arranged at spaced locations from one another and are provided on an inner circumference of the at least one connecting branch receiving opening;

the at least one connecting branch receiving opening has a lateral connecting branch insertion opening;

wherein a connection opening is associated with the connecting branch to be provided on the heat transfer medium assembly unit and the connection opening is to be brought into fluid-tight heat transfer medium flow connection with the connecting branch and is provided in the heat exchanger body;

wherein at least one of the flexible fixing elements comprises a fixing tongue formed integrally with the housing part and protruding into the at least one connecting branch receiving opening; and

wherein at least one of (a) the at least one of the flexible fixing elements is provided in a first circumferential area of the at least one connecting branch receiving opening located opposite the lateral connecting branch insertion opening and (b) the at least one of the flexible fixing elements is provided in a second circumferential area adjoining the lateral connecting branch insertion opening with respect to a circumferential direction.

7. The heat exchanger arrangement in accordance with claim 6 , wherein:

the housing part is fixable to the heat exchanger body for fixing the connecting branch mounted in the connecting branch receiving opening, whereby the connecting branch is secured against rotation by a positive-locking meshing of a first positive-locking meshing formation with second positive-locking meshing formation and is held by the housing part against elimination of the flow connection with the connection opening.

8. A method of manufacturing the heat exchanger arrangement in accordance with claim 6 , the method comprising the steps of:

inserting the connecting branch into the at least one connecting branch receiving opening of the housing part and thereby providing the connecting branch-housing part pre-assembled unit by:

generating a positive-locking meshing securing the connecting branch against rotation in the at least one connecting branch receiving opening receiving the connecting branch between a first positive-locking meshing formation of the housing part and a second positive-locking meshing formation of the connecting branch; and

fixing the connecting branch in the at least one connecting branch receiving opening against displacement in relation to the housing part by at least one said flexible fixing element acting between the connecting branch and the housing part;

positioning the connecting branch-housing part pre-assembled unit in relation to the heat exchanger body such that the connecting branch comes into flow connection with the connection opening provided in the heat exchanger body; and

fixing the housing part on the heat exchanger body.