FR2794605A1 - HEATING DEVICE, PARTICULARLY FOR A MOTOR VEHICLE - Google Patents

Abstract

The invention relates to a heating device, in particular for a motor vehicle. This heating device is of the type comprising a heating block (2) surrounded by a frame (3, 4) and which can be crossed by the air to be heated, and in which are arranged several electric heating elements (5) which are controlled by a control device comprising control components (7) which give off heat. According to the invention, the control components (7) which give off heat are integrated into the space of the heating unit (2). Main application: auxiliary heater for heating an interior space of a vehicle.

Description

Heating device, in particular for a motor vehicle

  The invention relates to a heating device, in particular for a motor vehicle, comprising a heating block surrounded by a frame and which can be traversed by air to be heated and in which are arranged several electric heating elements which can be controlled. by a control device fitted with components

  that generate heat.

  Such a heating device is known from the document DE 197 38 318 AI, in particular intended to be used as auxiliary heating for a motor vehicle, to ensure rapid heating of the interior space of the vehicle during starting from vehicle cold. The heating device has several PTC heating units gathered in a heating block and between which are respectively arranged corrugated fins which are traversed by the air to be heated. The heating block, including the PTC heating units and the corrugated fins, is surrounded by a frame. On this frame is fixed a control device for controlling the PTC heating units. Here, radiators to which power transistors of the control device are connected are arranged on a lateral segment of the frame, on the side which is opposite the heating block. Power transistors are control components that generate heat. The presence of the radiators which are arranged at least in part in the air flow of a heat transmission member placed in front, guarantees that the air which licks the radiators at the same time ensures cooling of the power transistors. At the same time, the heat given off by the power transistors to the air which licks them ensures an additional heating of

  the air intended for the interior space of the vehicle.

  The object of the invention is to create a heating device of the kind mentioned in

  beginning which presents a simplified construction compared to the state of the art.

  This problem is solved by the fact that the control components which generate heat are integrated in the space surrounded by the frame, in the region of the heating block. By spatially integrating the control components which release

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  heat in the heating block and, therefore, in the space surrounded by the frame, it ensures the passage of air on the control components which generate heat, regardless of the arrangement of the device heating behind a heat transfer member which is of a correspondingly enlarged form, thanks to which an extremely simple construction achieves cooling of the control components and, at the same time, additional heating of the air which it it's about heating. The control components can be attached either directly to

  corresponding parts of the heating block, or still on an inner side of the frame.

  In one embodiment of the invention, there is provided, associated with at least one heating element or at least one group of at least two heating elements, an electronic switching element, in particular a power transistor, which represents a control component which generates heat and which is connected to the corresponding heating element or to the corresponding group of heating elements by an electrically conductive link. This embodiment is particularly well suited for controlling PTC heating units, the control device comprising a power electronics provided with electronic switching elements, in particular power transistors, as well as a control logic associated with power electronics, as is known in

  principle by document DE 197 38 318 AI.

  In another embodiment of the invention, the heating elements are provided with electrically conductive contact extensions which project on the front side in the longitudinal direction of the heating elements, and on which the corresponding electronic switching elements are fixed. Preferably, in order to form the electrically conductive contact extensions, the contact sheets which simply form ceiling or floor parts in the PTC heating units are simply extended to a front end. This

  guarantees simple and secure mounting of electronic switching elements.

  In another embodiment of the invention, the electronic switching elements are fixed to the contact extensions by links acting by force action, by material continuity or by shape safety. Appropriate assembly possibilities are in particular gluing, welding, clamping,

riveting or bolting.

  According to another embodiment of the invention, the electronic switching elements are fixed to the contact extensions by clamping devices. The

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  clamping devices surround the electronic switching elements, at least in places, in such a way that a fixing operating in form safety can be obtained in particular. The clamping devices are preferably made in the form of radiators, in the sense that they are made of a heat conductive material, preferably metal. In another embodiment of the invention, the clamping devices are provided with conductive bridges each connecting them to a contact extension of an adjacent heating element. In this way, it is possible to connect at least two heating elements in parallel or in series with simple means, so that a single electronic switching element is provided for switching on or off a group of at least two heating elements. The number of elements

  electronic switching to use can thus be reduced.

  According to another characteristic of the invention, the clamping devices are anchored in a lateral part of the frame. In this way, the electronic switching elements are connected both to the contact extensions of the heating block

than at the frame.

  According to another characteristic of the invention, the clamping devices are each fixed on two adjacent contact extensions, by a link operating by force or continuity of material. In this way, the clamping devices, if they are made electrically conductive, can also directly form the bridges

  conductors for the electrical connection of two adjacent heating elements.

  According to another characteristic of the invention, the clamping devices are provided with retaining segments operating by form safety or by force action for fixing the electronic switching elements. The clamping devices can therefore be used in a simple manner both to establish the electrically conductive connection of two heating elements and to each fix one

electronic switching.

  According to another characteristic of the invention, the heating block is provided with corrugated fins which extend between the heating elements and which, by extending, each extend between two contact extensions of adjacent heating elements. In this way, it is certain to obtain a particularly good evacuation of the heat as well as support for the contact extensions, in particular in the

  mounting region of electronic switching elements.

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  In another embodiment of the invention, data transmission means intended for controlling the electronic switching elements placed in the heating block, are integrated in the lateral part of the frame. In this way, power supply lines as well as data buses extend inside the side part of the frame, however a corresponding plug connection.

  can be provided against the outside of the frame.

  Other advantages and characteristics of the invention emerge from the description

  which will follow from an exemplary embodiment of the invention, which is shown in the drawings. Fig. 1 shows a view of an embodiment of a heating device according to the invention comprising a heating block formed by PTC heating units and corrugated fins interposed therebetween and FIG. 2 is a perspective representation of a fragment of the

heating according to Fig. 1.

  A heating device I according to FIGS. I and 2 is intended to be used in a motor vehicle, as an auxiliary heater, to heat the air which must be sent to the interior space of the motor vehicle as long as the heat given off by the heating circuit and cooling the internal combustion engine of the vehicle is not yet sufficient to ensure sufficient heating of the interior space of the vehicle. The heating device comprises a heating block 2 which is composed of several electric heating elements arranged in parallel with one another, presented in the form of PTC heating units 5, as well as a plurality of corrugated fins 6 arranged between these units heating PTC 5. The heating block 2 is held in a frame 3, 4 which completely surrounds the heating block 2. In the aspect of the principle construction of the heating block, the heating device I corresponds to a device electric heating such as that known from document DE 197 38 318 AI or

by document DE 44 34 613 AI.

  Associated with the PTC 5 heating units is a control device composed of control logic and power electronics, the control components which generate heat, here electronic switching elements constituted by power transistors 7 , being spatially integrated inside the frame 3, 4, in the region provided for the heating block 2. All the power transistors 7 are connected, by means of data transmission lines, not referenced in detail, to a side part 4 of the frame 3, 4, and they are positioned in s 2794605 a region of the heating block 2 which is adjacent to the side part 4. Corresponding data transmission lines as well as corresponding power supply lines are integrated in the side part 4 and, on the input side, a plug-in connection 10 for the data transmission lines is arranged on one side

  s outside of the side part 4 of the frame 3, 4.

  The power transistors 7 provided for controlling the PTC heating units 5 are each connected to a contact extension 8 of the corresponding PTC heating units 5. These corresponding contact extensions 8 consist of front extensions of contact sheets integrated in the PTC heating 0o units 5, which protrude beyond the envelope profile of the PTC heating elements in the direction of the lateral part 4 of the frame. 3, 4, and overlapping on both

  sides of the PTC elements contained in the PTC heating unit.

  To connect the power transistors 7 to the contact extensions 8, the latter are fixed to the contact extensions 8, either by links operating by continuity of material, preferably by bonding, or by links operating by form safety, by riveting or bolting, or, finally, by links operating by force action, by tightening. In the exemplary embodiment according to FIGS. I and 2, a total of five power transistors 7 are provided, to which five groups a, b, c, d, e are respectively associated, each comprising two PTC heating units 5. All the power transistors 7 are fixed to the extensions of contact 8 by means of

  different clamping devices 9a to 9e.

  Two adjacent heating elements 5 are electrically connected to each other by a clamping device 9_a to 9e, by the fact that one of the two contact sheets of each pair of contact sheets which encloses a heating element between them PTC are extended towards the lateral part 4 of the frame 3, 4 to each constitute a contact extension 8 or 17 respectively. In the embodiment shown, these are the mutually opposite contact sheets of adjacent heating elements, so that, under the effect of the conductive bridge formed by means of the corresponding clamping device 9a to 9e, a series connection between two adjacent heating elements of each group a to e. To obtain, on the one hand, a consolidation and support of the contact extensions 8, 17 framed by the conductive bridge of the corresponding clamping device 9a to 9e and, on the other hand, good heat dissipation, also in the region of the extended contact extensions 8, 17, the corrugated fins 6 are extended in the region between the

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  adjacent contact extensions 8, 17, approximately to the front ends of contact extensions 8, 17. The power transistors 7 are each arranged on the outside of the corresponding contact extension 8 which is opposite to

the extended wavy fin 6.

  To provide additional fixing and to constitute the sole mounting of the power transistors 7 on the contact extensions 8, each clamping device 9a to 9e is provided with a retaining segment 11, 12, 13, 14, 15 respectively in the form of a leg which surrounds the power transistor 7, at least in places, and blocks it for safety of form. In the exemplary embodiment according to FIGS. I and 2, all the power transistors 7 are fixed and / or immobilized with different retaining segments 11 to 15, while, for an embodiment used in practice, preferably only a single configuration of a segment will be provided the same configuration for mounting and / or fixing all power transistors. The retaining segments 1 I to 15 can also exert a clamping force on the power transistors by the fact that they are held with the possibility of yielding elastically within certain limits thanks to their shape of lug. The retaining segments 11, 12 and 15 of the clamping devices 9a, 9b and 9e are additionally anchored to the lateral part 4 of the frame 3, 4 by means of a support rib 16, in order to reduce any stresses on the connection lines of power transistors 7

respective.

  Since both the contact extensions 8, 17 and the clamping devices 9a to 9e, including the retaining segments 1 1 to 15, are made of a material which conducts electricity as well as heat, preferably made of a metal, the retaining segments 1 1 to 15 as well as the contact extensions 8 form radiators for the power transistors 7, in the sense that in service, with their regions pressed flat, they may fail in supplement to the air flow which licks the corresponding heat from the power transistor 7. This is all the more so as the corrugated fins are extended as far as the mounting region of the power transistors 7. Since the power transistors 7 are arranged inside the space which is surrounded by the frame 3, 4 and, in this way, entirely traversed by the air, we obtain in a particularly simple way a good cooling of the transistors

  power 7, at the same time additional heating of the air passing through.

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Claims (10)

  1. Heating device, in particular for a motor vehicle, comprising a heating block surrounded by a frame and which can be traversed by air to be heated and in which are arranged several electric heating elements which can be controlled by a device control unit with control components which generate heat, characterized in that the control components (7) which generate heat are integrated in the space surrounded by the frame (3, 4), in the region of the heating block (2).   2. Heating device according to claim 1, characterized in that it is provided, associated with at least one heating element (5) or with at least one group (a to e) of at least two heating elements (5) , an electronic switching element, in particular a power transistor (7) which represents a control component which generates heat and which is connected to the corresponding heating element (5) or to the   corresponding group (a to e) of heating elements (5).   3. Heating device according to claim 2, characterized in that the heating elements (5) are provided with contact extensions (8) electrically conductive which project on the front side in the longitudinal direction of the heating elements (5 ), and on which the electronic switching elements (7) correspondents are set.   4. Heating device according to claim 3, characterized in that the electronic switching elements (7) are fixed on the contact extensions (8) by connections operating by force action, by material continuity or by safety of form.   5. Heating device according to claim 4, characterized in that the electronic switching elements (7) are fixed to the contact extensions (8)   by clamping devices (9a to 9e).   6. Heating device according to claim 5, characterized in that the clamping devices (9a to 9e) are provided with conductive bridges each connecting them to a contact extension (1 7) of a heating element (5) adjacent 8 2794 605   7. Heating device according to claim 5, characterized in that the   clamping devices (9a, 9b, 9e) are anchored in a lateral part (4) of the frame (3, 4).   8. Heating device according to claim 6, characterized in that the clamping devices (9a to 9e) are each retained on two adjacent contact extensions (8, 17) by connections operating by force action or by material continuity . 9. Heating device according to claim 8, characterized in that the clamping devices (9a to 9e) are provided with retaining segments (1 1 to 15) operating by form safety and / or by force action for fixing switching elements electronic (7).   10. Heating device according to one of the preceding claims, characterized   in that the heating block (2) is provided with corrugated fins (6) extending between the - heating elements (5) which, extending, each extend between two   contact extensions (8, 17) of adjacent heating elements (5).   1 1. Heating device according to one of the preceding claims, characterized   in that, in the lateral part (4) of the frame (3, 4), there are integrated data transmission means intended for controlling the switching elements   electronic (3) contained inside a heating block (2).