Heat-Generating Element of a Heating Device

• US 20080073336A1
• Filed: 03/07/2007
• Published: 03/27/2008
• Est. Priority Date: 09/22/2006
• Status: Active Grant

• Current Assignee: Catem GmbH & Co., KG
• Original Assignee: Catem GmbH & Co., KG
• Inventors: Zeyen, Michael, Bohlender, Franz, Niederer, Michael, Walz, Kurt
• Granted Patent: US 7,576,305 B2
• Time in Patent Office: Days
• US Class Current: 219/467.1
• CPC Class Codes: F24H 3/0429 For vehicles
• CPC Class Codes: F24H 3/0435 Structures comprising heat spreading elements in the form of fins
• CPC Class Codes: F24H 3/0447 Forms of the electrode terminals, e.g. tongues or clips
• CPC Class Codes: F24H 3/0464 Two-piece frames, e.g. two-shell frames, also including frames as a central body with two covers
• CPC Class Codes: F24H 3/0476 Means for putting the electric heaters in the frame under strain, e.g. with springs
• CPC Class Codes: F24H 3/082 The tubes being an electrical isolator containing the heater
• CPC Class Codes: F24H 9/1863 Arrangement or mounting of electric heating means
• CPC Class Codes: F24H 9/1872 PTC
• CPC Class Codes: H05B 2203/02 Heaters using heating elements having a positive temperature coefficient
• CPC Class Codes: H05B 2203/023 Heaters of the type used for electrically heating the air blown in a vehicle compartment by the vehicle heating system
• CPC Class Codes: H05B 3/50 heating conductor arranged in metal tubes, the radiating surface having heat-conducting fins

Abstract

A heat-generating element of a heating device for heating air including at least one PTC element, electric strip conductors lying on the PTC elements and a longish positioning frame that forms at least one frame opening for holding the minimum of one PTC element. A heat-generating element that is improved with a view to safety from electric flashovers and leakage currents is created with the invention under consideration by providing at least one insulating layer, which covers the strip conductor on its exterior side that is turned away from the positioning frame. The insulating layer in any case is sealed against the long sides of the positioning frame by a compressible sealing bead. A heating device for heating air with multiple heat-generating elements is also disclosed.

Claims

1. A heat-generating element of a heating device for heating air, comprising:

at least one PTC element;

electric strip conductors lying on the PTC element;

an elongated positioning frame that forms at least one frame opening for holding the minimum of one PTC element; and

at least one insulating layer that covers the strip conductors on their exterior side facing away from the positioning frame,

wherein

the insulating layer is sealed against at least long sides of the positioning frame by at least one compressible sealing bead.

2. The heat-generating element according to claim 1, wherein the sealing bead is formed continuously along the length of the positioning frame.

3. The heat-generating element according to claim 1, wherein the sealing bead is glued onto the positioning frame.

4. The heat-generating element according to claim 1, wherein the sealing bead is glued to the insulating layer.

5. The heat-generating element according to claim 3, wherein the sealing bead is glued to the insulating layer.

6. The heat-generating element according to claim 1, wherein the sealing bead is formed from a highly insulating plastic.

7. The heat-generating element according to claim 1, further comprising a securing structure that encompasses the insulating layer along the edge of an exterior side thereof.

8. The heat-generating element according to claim 7, wherein the securing structure creates at least one of a pre-tensioning force that presses the strip conductor against the assigned PTC element and a pre-tensioning force that sealingly holds the insulating layer against the sealing bead.

9. The heat-generating element according to claim 7, wherein the securing structure is formed by molding around the positioning frame.

10. The heat-generating element according to claim 9, wherein the securing structure is formed as a single piece on the positioning frame.

11. The heat-generating element according to claim 7, wherein the securing structure is formed by a clamp element that encompasses at least the exterior side of the heat-generating element.

12. The heat-generating element according to claim 11, wherein the clamp element is formed as a separate component.

13. The heat-generating element according to claim 11, wherein the clamp element encompasses the heat-generating element on both sides.

14. The heat-generating element according to claim 7, wherein the securing structure is formed onto the positioning frame as a single piece and in such a way that it is pivotable relative to the positioning frame.

15. The heat-generating element according to claim 14, wherein the securing structure comprises two locking arms that encompass the insulating layer surrounding the outside of the positioning frame, and wherein said locking arms are connected to the middle of the positioning frame via a shared hinged joint.

16. The heat-generating element according to claim 15, wherein the locking arms encompass a face side of the insulating layer.

17. The heat-generating element according to claim 1, wherein at least one positioning frame head, which is formed frontally on the positioning frame and which projects beyond the insulating layers on at least one exterior and top sides of the insulating layer, positions these layers with respect to the positioning frame.

18. The heat-generating element according to claim 7, wherein the positioning frame head forms at least one lead-through opening for a contact tongue that is provided on one of the strips of metal forming the strip conductors.

19. The heat-generating element according to claim 18, wherein the positioning frame head supports the locking arms.

20. The heat-generating element according to claim 1, wherein at least one of the insulating layers and the strip conductor covered by the associated insulating layer is secured to the positioning frame by being molded around it and is sealed with respect to this positioning frame at least in a lengthwise direction thereof, and wherein the insulating layer on the opposite side of the positioning frame lies against the positioning frame, with the compressible sealing bead being placed in between.

21. The heat-generating element according to claim 1, wherein the insulating layer is formed by a flat ceramic plate.

22. The heat-generating element according to claim 1, wherein the insulating layer extends along at least essentially the entire width of the positioning frame.

23. Heat-generating element according to preceding claim 1, wherein the heat-generating element is formed as a layered, pre-fabricated unit comprising the positioning frame, two insulating layers attached thereto in such a way as to form a seal, two electric strip conductors provided in between, and at least one PTC element provided in between.

24. The heat-generating element according to claim 23, wherein the side surface of the layered unit is essentially formed by a side wall of the positioning frame.