Insulated heating module for a supplemental heating device

Abstract

The invention relates to a heating module for a supplemental electric heating device for heating an airflow, comprising at least one heat-conductive bar against which at least one electric resistor is arranged. The heat-conductive bar is partially electrically insulated by an insulating coating in order to prevent potential short-circuits and to ensure proper operation and optimal safety when heating the passenger compartment of a vehicle.

Claims

1. A heating module (100) of a supplemental heating device (10) for heating an airflow, the heating module (100) comprising at least one heat-conductive bar (5) against which at least one electrical resistor (6) is disposed, the at least one heat-conductive bar comprising at least one insert (2), an electrode (1), and a plate (3) having the at least one insert (2) disposed between the electrode (1) and the plate (3), wherein the heat-conductive bar (5) is partially electrically insulated, and the electrical resistor (6) is disposed against the plate (3).

2. The heating module (100) as claimed in claim 1, wherein the electrical resistor (6) comprises at least one resistor having a positive temperature coefficient (PTC).

3. The heating module (100) as claimed in claim 1, wherein the electrode (1) is in direct contact with the connector (11).

4. The heating module (100) as claimed in claim 1, wherein the inserts (2), the connector (11) and the electrode (1) comprise aluminum.

5. The heating module (100) as claimed in claim 1, wherein the electrode (1) and the inserts (2) and/or the resistor (6) are disposed on the heat-conductive bar (5) by a conductive adhesive material.

6. The heating module (100) as claimed in claim 1, wherein the electrode (1) and the resistor (6) are electrically insulated by an insulating coating (19).

7. The heating module (100) as claimed in claim 6, wherein the inserts (2) and/or the plate (3) are electrically insulated by an insulating coating (19).

8. The heating module (100) as claimed in claim 6, wherein the insulating coating (19) comprising polyester.

9. The heating module (100) as claimed in claim 8, wherein the insulating coating (19) has a thickness of between 20 and 120 m.

10. A supplemental heating device (10) comprising at least one heating module (100) as claimed in claim 1.

11. The heating module (100) as claimed in claim 2, wherein the heat-conductive bars (5) comprise at least one insert (2) disposed between, on the one hand, a connector (11) and/or an electrode (1) and, on the other hand, a plate (3).

12. The heating module (100) as claimed in claim 1, wherein the electrode (1) is in direct contact with the connector (11).

13. The heating module (100) as claimed in claim 5, wherein the conductive adhesive material is a conductive glue.

Description

(1) Other advantages and features of the invention will emerge from the description of embodiments given hereafter with reference to the appended drawings in which:

(2) FIG. 1 is a perspective view of a heat-conductive bar according to a first embodiment of the present invention;

(3) FIG. 2 is a perspective view of a heating module according to the present invention;

(4) FIG. 3 is a detailed perspective view of a first end of the heat-conductive bar shown in FIG. 1;

(5) FIG. 4a is a detailed perspective view of a second end of the heat-conductive bar shown in FIG. 1;

(6) FIG. 4b is a detail view of FIG. 4a of an insert of the heat-conductive bar shown in FIG. 1;

(7) FIG. 5 is a front view of a first embodiment of the present invention;

(8) FIG. 6 is a front view of a second embodiment of the present invention; and

(9) FIG. 7 is a perspective view of a supplemental heating device according to the present invention.

(10) FIG. 8 is a detail view of FIG. 5; and

(11) FIG. 9 is a detail view of a part of FIG. 6.

(12) With reference to FIG. 1, the figure shows a heat-conductive bar 5 in detail. The heat-conductive bar 5 comprises an insert 2, an electrode 1 and a plate 3. The insert 2 is in contact with the electrode 1 and the plate 3. The insert 2 is in the form of a corrugated metal sheet, advantageously made of aluminum or of aluminum alloy. The corrugation of the metal sheet is obtained by folding or by passing the sheet between shaping wheels. The corrugated metal sheet thus has a zigzag shape. This particular shape thus creates peaks 9 that are the curved parts of the corrugated metal sheet and are alternately in direct contact with the electrode 1 and with the plate 3.

(13) The plate 3 provides the electrical contact between the electrode 1 and a resistive element 6 via the insert 2 and the thermal contact between the insert 2 and the resistive element 6. The plate 3 is preferably made of aluminum or of aluminum alloy. It is of generally flat shape apart from at its ends. The flat part is in electrical and thermal contact with the peaks 9 of the insert 2.

(14) The resistive element 6 is advantageously a resistor with a positive temperature coefficient (PTC). The resistive element 6 gives off heat when an electrical current passes through it. The element having a positive temperature coefficient has the feature of being self-regulating, that is to say that the electrical resistance increases as the temperature of the element increases, which prevents any risk of overheating.

(15) The insert 2 makes it possible to dissipate the heat produced by the resistive element 6 by heat exchange with an airflow passing across the heat-conductive bar 5.

(16) The electrode 1 is a metal strip 12 in contact with the insert 2 and has, at one end, a termination 4 which provides the electrical connection between the resistive element 6 and the electrical energy generated by the vehicle. The electrode 1 is preferably made of aluminum or of aluminum alloy. Similarly, the termination 4 is preferably made of aluminum or of aluminum alloy.

(17) FIG. 2 shows a heating module 100 according to the invention. Such a heating module 100 is located inside an electrical heating device 10, shown in FIG. 7, comprising a plurality of heating modules 100. Such an electrical heating module 10 is installed within a heating, ventilation and/or air-conditioning system of a motor vehicle in order to produce a warm airflow suitable for being distributed in the passenger compartment, in particular starting from the first moments of operation of the vehicle.

(18) The heating module 100 comprises at least one resistive element 6 and two heat-conductive bars 5. The resistive element 6 is bonded to the heat conductive bars 5.

(19) The two heat-conductive bars 5 are disposed on either side of the resistive element 6. In this way the two heat-conductive bars 5 are each disposed on a large face of the resistive elements 6. The expression large face refers to the face of the PTC resistive elements having the biggest dimensions.

(20) FIG. 3 shows one of the ends of the heat-conductive bar 5 and, in particular, the end providing the electrical connection of the heating module 100 to the electrical system of the vehicle. According to FIG. 3, the insert 2 is sandwiched between the electrode 1 and the plate 3. The electrode 1 comprises a flat part and a curved part. The flat part of the electrode 1 is in electrical contact with the peaks 9 of the insert 2.

(21) The electrode 1, in the form of a metal strip 12, has a tongue 7 at one end. The tongue 7, connected to the metal strip 12 by a bend 8, is itself sandwiched by the termination 4. Preferably, the tongue 7 is disposed perpendicular to the metal strip 12 since the bend 8 forms an angle of 90 thus advantageously forming an L shape.

(22) The termination 4, preferably made of aluminum, comprises a flat connector 11 for connection to the electrical system of the vehicle and an arm 13 providing the contact. In a preferred embodiment, the arm 13 has a U shape clamping the tongue 7 of the electrode 1. The mechanical connection between the tongue 7 and the arm 13 is the part of the heat-conductive bar 5 which is received inside a positioning means that is not shown.

(23) FIG. 4a shows the other end of the heat-conductive bar 5 which is opposite to the end shown in FIG. 3. According to FIG. 4a, the insert 2 is sandwiched between the electrode 1 and the plate 3. The peaks 9 of the corrugated metal sheet forming the insert 2 are alternately in direct contact with the electrode 1 and the plate 3. The electrode 1 has a second tongue 7 connected to the metal strip 12 by a bend 8. Moreover, the plate 3 is terminated by a bent terminal 14. The terminal 14 is advantageously disposed perpendicular to the plate 3 in such a way as to extend in a direction parallel with the direction of the tongue 7. A gap 15 separates the tongue 7 from the terminal 14 in order to prevent electrical continuity between the electrode 1 and the plate 3.

(24) FIG. 4b shows a detail view of the structure of the insert 2, covered on both sides of the metal sheet by an insulating coating layer 19, preferably made of silicone or of polyester.

(25) FIG. 5 shows the heating module in a first embodiment. The resistive element 6 is bonded to the heat-conductive bar 5 on the side where the plate 3 is situated. The plate 3 is situated inside the heating module 100 and the electrode 1 is situated on the outside of the heating module 100. The resistive element 6 can advantageously be fitted with an insulating element 19. Preferably, the electrode 1 and the plate 3 have curves at their ends. The resistive element 6, the plates 3 and the inserts 2 are sandwiched between the electrodes 1.

(26) FIG. 6 shows the heating module in a second embodiment. The resistive element 6 is bonded to the heat-conductive bar 5 on the side where the electrode 1 is situated. The electrode 1 is situated inside the module 100 and the plate 3 is situated on the outside of the module 100. The resistive element 6 can advantageously be fitted with an insulating element. Preferably, the electrode 1 and the plate 3 have curves at their ends. The resistive element 6, the electrodes 1 and the inserts 2 are sandwiched between the plates 3.

(27) As shown in FIG. 7, the supplemental heating device 10 comprises a frame 18, for example made of plastic, in which is housed a plurality of heating modules 100. The heating modules 100 are disposed parallel with each other and extend over the whole length of the frame 18 in such a way as to be exposed directly to the air passing through the frame 18. In the non-limiting example shown in FIG. 7, the supplemental heating device 10 comprises three heating modules 100.

(28) FIG. 8 shows a detail view of FIG. 5 illustrating the heating module in the first embodiment. According to the first embodiment, the plate 3 and the resistive element 6 are respectively covered by an insulating coating 19, preferably made of silicone or of polyester. Advantageously, the thickness of the insulating coating layer 19 is between 20 and 120 m. According to the first embodiment, the bonding between the plate 3 and the resistive element 6 is carried out before depositing the insulating coating 19.

(29) FIG. 9 shows a detail view of FIG. 6 illustrating the heating module in the second embodiment. According to the second embodiment, the electrode 1, the insert 2, the plate 3 and the resistive element 6 are respectively covered with the insulating coating 19, preferably made of silicone or of polyester. Advantageously, the thickness of the insulating coating layer 19 is between 20 and 120 m. According to the second embodiment, the bonding between the plate 3 and the resistive element 6 is carried out before depositing the insulating coating 19.

(30) Moreover, according both of the embodiments, the assembly between the electrode 1 and the connector 11 is also carried out before depositing the insulating layer 19. The connector 11 is not however covered by the insulating coating 19.