Cooling module for a vehicle control unit, vehicle control unit with a cooling module and method for water cooling a vehicle control unit

Abstract

The invention relates to a cooling module for a vehicle control unit, comprising a cooling element, connections for conducting a coolant through the cooling element, a turbulence insert placed in the cooling element comprising at least first cooling fins, and at least one first bimetal located in the cooling element, wherein the at least one first bimetal is placed such that it displaces the at least one group of first cooling fins depending on a temperature-dependent shape change of the at least one first bimetal. The invention also relates to a vehicle control unit with a cooling module and a method for water cooling a vehicle control unit.

Claims

1. A cooling module for a vehicle control unit, comprising: a cooling element; connections, for conducting a coolant through the cooling element; a turbulence insert comprising at least a first set of cooling fins located on the cooling element; and at least a first bimetal located in the cooling element, wherein the first bimetal comprises two metals with different linear expansion coefficients connected to one another in a material bonding or form fitting manner, wherein the at least the first bimetal is placed such that it displaces the first set of cooling fins depending on a temperature-dependent change in shape of the at least the first bimetal, wherein the first set of cooling fins extend between the first bimetal and a sidewall of the cooling element in a direction transverse to a longitudinal direction of the cooling element, wherein a central axis of the first bimetal is parallel to the longitudinal direction of the cooling element, wherein the first bimetal includes a first end and a second end that is opposite to the first end across the first bimetal such that the central axis is located between and substantially parallel to the first end and the second end of the first bimetal, wherein the first end and the second end of the first bimetal are connected to the cooling element, and wherein a first end of the first set of cooling fins is connected to a first side of the cooling element, and a second end of the first set of cooling fins is located at the first bimetal, wherein the first set of cooling fins is configured to be displaced by a temperature-dependent bending of the first bimetal.

2. The cooling module according to claim 1, comprising: a second set of cooling fins; a second bimetal located in the cooling element, which is parallel to the first bimetal, wherein the second set of cooling fins extend between the second bimetal and a sidewall of the cooling element in a direction transverse to a longitudinal direction of the cooling element wherein a first end of the second set of cooling fins is connected to a second side of the cooling element lying opposite the first side of the cooling element, and a second end of the second set of cooling fins is located at the second bimetal, wherein the second set of cooling fins is configured to be displaced by a temperature-dependent bending of the second bimetal.

3. The cooling module according to claim 1, wherein the first set of cooling fins are at least one of welded or rivetted at their first ends to the cooling element.

4. The cooling module according to claim 1, wherein the first cooling fins are wave-shaped.

5. The cooling module according to claim 1, wherein the at least one bimetal has a lamellar structure.

6. A vehicle control unit comprising a cooling module according to claim 1.

7. The vehicle control unit according to claim 6, wherein the cooling module is flange-mounted on the vehicle control unit.

8. The vehicle control unit according to claim 6, wherein a thermal conductor is located between the vehicle control unit and the cooling module.

9. A method for water cooling a vehicle control unit, comprising: conducting a coolant through a cooling module via connections to the cooling module, wherein the cooling module is in thermal contact with the vehicle control unit and comprises: a cooling element; a turbulence insert comprising at least a first set of cooling fins located on the cooling element; and at least one bimetal located in the cooling element and configured to displace the first set of cooling fins depending on a temperature-dependent change in shape of the at least one bimetal, wherein the at least one bimetal comprises two metals with different linear expansion coefficients connected to one another in a material bonding or form fitting manner, wherein the first set of cooling fins extend between the at least one bimetal and a sidewall of the cooling element in a direction transverse to a longitudinal direction of the cooling element, wherein a central axis of the at least one bimetal is parallel to the longitudinal direction of the cooling element, wherein the at least one bimetal includes a first end and a second end that is opposite to the first end across the at least one bimetal such that the central axis is located between and substantially parallel to the first end and the second end of the at least one bimetal, wherein the first end and the second end of the at least one bimetal are connected to the cooling element, and wherein a first end of the first set of cooling fins is connected to a first side or a second side of the cooling element lying opposite the first side, and a second end of the first set of cooling fins is located at the at least one bimetal, generating a turbulent flow of the coolant through the cooling module by means of the turbulence insert; and altering the volumetric flow rate of the coolant through the cooling module by displacing the first set of cooling fins with the at least one bimetal depending on the temperature-dependent change in shape of the at least one bimetal.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention shall now be explained in terms of the exemplary embodiments. In the drawings:

(2) FIG. 1 shows a cross section of an exemplary embodiment of a cooling module according to the invention;

(3) FIG. 2 shows the exemplary embodiment from FIG. 1, cut along line I;

(4) FIG. 3 shows an exemplary embodiment of a cooling module according to the invention with the two bimetals in a starting position;

(5) FIG. 4 shows the exemplary embodiment from FIG. 3 with the bimetals in a bent position; and

(6) FIG. 5 shows an exemplary embodiment of a method according to the invention.

(7) Identical reference symbols indicate identical or functionally similar components in the figures. For purposes of clarity, only the relevant components are indicated in the individual figures.

DETAILED DESCRIPTION

(8) The cooling module 10 in FIG. 1 comprises a cooling element 11. The cooling element 11 has a first side 11a. The first side 11a is a lower surface of the cooling element 11, by way of example, cf. FIG. 3. The cooling element 11 also has a second side 11b. The second side 11b is an upper surface of the cooling element 11, by way of example, cf. FIG. 3. A coolant is conducted through the cooling element 11. The coolant is a water and ethylene glycol mixture, by way of example. The cooling element 11 forms channels, for example, through which the coolant is conducted.

(9) A U-shaped channel is shown by way of example in FIG. 2. Alternatively, additional channels or upright pins are placed in the region of the first connection 12a and/or second connection 12b, for conducting the coolant in a targeted manner through the cooling element 11 or for homogenizing the coolant in the cooling element 11. The bidirectional arrows in the cooling element 11 shown in FIG. 2 indicate the direction of expansion of a first bimetal 14a and second bimetal 14b between the respective securely riveted or welded end points thereof, cf. FIG. 3. The cooling module 10 comprises a first connection 12a. The coolant is conducted into the cooling element 11 via the first connection 12a. The first connection 12a is in the form of an intake valve. The cooling module 10 comprises a second connection 12b. The coolant is conducted out of the cooling element via the second connection 12b. The second connection 12b is in the form of an outlet valve.

(10) The cooling module 10 is flange-mounted on the vehicle control unit 20 in the figures, wherein a thermal conductor 15 is located between the cooling module 10 and the vehicle control unit 20.

(11) FIG. 3 shows first cooling fins 13a and second cooling fins 13b. The first cooling fins 13a and second cooling fins 13b are placed above one another and are each wave- or S-shaped, wherein the shape of the second cooling fins 13b is vertically mirrored in relation to the shape of the first cooling fins 13a. The first cooling fins 13a are welded, for example, at a first end 131a to the first side 11a of the cooling element, and slide at a second end 132a toward a first bimetal 14a. The second cooling fins 13b are welded, for example, at a first end 131b to second side 11b of the cooling element 11, and slide at a second end 132b toward a second bimetal 14b. The arrangement of the first cooling fins 13a, second cooling fins 13b, first bimetal 14a and second bimetal 14b form a valve due to the temperature-dependent bending of the first bimetal 14a and second bimetal 14b. The valve is closed in FIG. 3. This corresponds to the state at temperatures above a threshold value. The valve is open in FIG. 4. This corresponds to the state at temperatures below the threshold value. The threshold value is −10° C., for example.

(12) When the valve formed by the first bimetal 14a and second bimetal 14b is open, see FIG. 4, heat is only dissipated via the thermal conductor 15 from the vehicle control unit 20 to the coolant via the first bimetal 14a and the first cooling fins 13a, but not via the second bimetal 14b with the second cooling fins 13b. At low temperatures, a highly efficient heat reduction is not yet needed.

(13) In FIG. 3, when the first bimetal 14a and the second bimetal 14b lie opposite one another such that they are flush with one another, however, the thermal transition also takes place from the first bimetal 14a to the directly adjacent second bimetal 14b. This provides more surface area for the thermal reduction, thus improving the thermal reduction.

(14) FIG. 5 illustrates the method according to the invention for water cooling the vehicle control unit 20. In a first step V1, the coolant is conducted through the cooling module 10. The cooling module 10 is in thermal contact with the vehicle control unit 20. In a second step V2, a turbulent flow of the coolant through the cooling module 10 is generated by means of the turbulence insert. In a second step V3, the volumetric flow rate of the coolant through the cooling module 10 is altered depending on the temperature by the change in shape of the first bimetal 14a and the second bimetal 14b.

REFERENCE SYMBOLS

(15) 10 cooling module 11 cooling element 11a first side 11b second side 12a connection 12b connection 13a cooling fin 131a first end 132a second end 13b cooling fin 131b first end 132b second end 14a bimetal 14b bimetal 15 thermal conductor 20 vehicle control unit L longitudinal direction V1-V3 method steps I section line