DE102011000765A1 - Heating device for, e.g. air conditioning apparatus of electric vehicle, has printed circuit board with several through holes for fluid such that heating element is indirectly or directly arranged with respect to through hole - Google Patents

Abstract

The heating device (1) comprises heating element (4) which is arranged in a printed circuit board (2), for heating the fluid flow (10). The printed circuit board is arranged vertical to the direction of flow. Several through holes for the fluid are formed in the printed circuit board such that the heating element is indirectly or directly arranged with respect to the through hole. The through holes are formed as several different recess patterns.

Description

The invention relates to a heating device for a fluid flow, in particular a gas or liquid flow according to the preamble of claim 1 and a circuit board for such a heater.

Such heaters are used for example for heating diesel fuel, air, for air conditioning of a vehicle interior or for space heaters in the home.

The EP 1 036 930 B1 discloses a heating device for diesel fuel, in which a heating element, in the specific case, a PTC resistance element is inserted into a flow path of the diesel fuel and is surrounded by this directly. The electronic control for the PTC resistor elements, which may be connected to one or more heating circuits, is located outside of the diesel fuel in a separate housing.

When using such a heater as a heater for an air conditioner or for a space heater, the PTC resistance elements are often thermally and / or electrically contacted with heating fins, which provide a comparatively large heat exchange surface for heat exchange with the air to be heated. In the EP 0 350 528 B1 the Applicant discloses such a heating device with a multiplicity of PTC components as heating elements and heating lamellae contacted therewith in the form of meander-shaped curved aluminum strip material.

The DE 10 2009 033 988 A1 shows a heater for heating a fluid flow, are accommodated in the PTC resistance elements in channels of an extruded profile, wherein the profile in the region between the transverse to the flow direction channels having a plurality of apertures, which are flowed through by the fluid flow. The one-piece extruded body serves on the one hand to receive the PTC resistor elements and on the other hand to increase the heat exchange surface.

In the latter two solutions, the controller is attached laterally in a separate housing to the actual heating elements. This can also be mounted in other places.

A disadvantage of all the above-described solutions is that these heaters have a very complex structure, which requires a considerable amount of space on the one hand and on the other hand can be made only with great effort. Since, in particular, the automobile industry is always anxious to design components with improved function simply and inexpensively, these solutions do not always meet the requirements of the industry.

In contrast, the present invention seeks to provide a heater with a simplified structure and a circuit board for such a heater.

This object is achieved by a heating device with the features of claim 1 and by a suitable for such a heating circuit board.

Advantageous developments of the invention are the subject of the dependent claims.

The heating device according to the invention is suitable for heating gaseous or liquid fluid streams and has at least one heating element, which is arranged in the fluid flow and emits heat when flowing around it. According to the invention, the at least one heating element is arranged on a printed circuit board, via which the heating element is contacted. This circuit board has openings for the fluid flow, wherein these are formed such that the heating element is flowed around directly or indirectly by the fluid flow.

In the solution according to the invention, the printed circuit board in contrast to conventional solutions has a dual function - it serves for a power supply and control of the at least one heating element, further serves as a flow guide, which is arranged directly in the fluid flow and thus determines the fluid flow and preferably so directs that the heating elements are lapped in a manner optimized for the exchange of heat.

In a further development of the invention, the apertures of the printed circuit board are designed as a recess pattern, which is optimized with regard to the optimum flow guidance, the desired heat distribution and also with regard to the contacting of the electronic components arranged on the printed circuit board.

Another essential advantage of the invention is that the electronic components positioned on the printed circuit board are likewise flowed around by the fluid flow and thus cooled.

According to the invention, it can be provided if the printed circuit board is designed with a plurality of different recess patterns, so that a placement of the heating elements and the printed conductors and electronic components is simplified by selecting the suitable recess pattern.

According to the invention it is preferred if the circuit board according to the SMD technology (surface-mounted device) are equipped and soldered, in which case the components including the heating elements are mounted substantially on one side of the circuit board. The devices may then be positioned relative to the flow to be located either upstream or downstream of the apertures.

The breakthroughs can be performed, for example, as circular holes, slots, elliptical recesses, etc.

In a variant, the circuit board can also be designed flexibly, so different designs for the heating element are possible.

In a variant of the invention, a plurality of heating elements or heating element groups are provided with different characteristics, so that they can be controlled, for example, depending on the ambient temperature in several heating circuits and thus deliver different benefits.

Advantageously, the electronic control for the heating elements can also be formed on the circuit board and thereby flow around the fluid flow, so that the actual control is cooled. In this case, the entire control system or else only a region of the control unit subject to particular thermal stress can be arranged in the fluid flow.

In a preferred embodiment of the invention, the fluid stream is air that is used for air conditioning the interior or even for heating drive elements, such as the battery of an electric vehicle or the like.

The circuit board is preferably positioned perpendicular to the flow direction and can be completely or partially in the fluid flow.

According to the invention it is preferred if the heating elements are designed as PTC resistor elements.

As already mentioned, the present application also covers a printed circuit board for such a heating device. This circuit board carries the heating elements and is designed with a plurality of openings which are arranged in the fluid flow and are flowed through by this for heat exchange with the heating element.

The breakthroughs of the circuit board can, as explained, be arranged in one or in a plurality of Ausnehmungsmustern.

A preferred embodiment of the invention will be explained in more detail below with reference to schematic drawings. Show it:

1 a highly schematic side view of a heater according to the invention;

2 a detailed view of the heater according to 1 and

3 a circuit board of the heater off 1 ,

The invention is explained below with reference to a heater for supply air of an air conditioner or for controlling the temperature of a gas stream. It shows 1 in a greatly simplified representation of a side view of the heater according to the invention 1 , This consists in principle of a printed circuit board 2 on which a plurality of heating elements, preferably PTC resistor elements 4 and other, electronic components are arranged, via the circuit board 2 are contacted. The assembly of the printed circuit board 2 takes place in the SMD process. This is sufficiently known to the person skilled in the art, so that further explanations of the function and the advantages of the SMD method are dispensable. As shown in 1 are the PTC resistor elements 4 preferably on a large surface of the circuit board 2 arranged. The control of the PTC blocks 4 via an electronic control 6 holding a variety of electronic components 8th also on the circuit board 2 are arranged and contacted via this.

The fluid flow to be heated is in 1 with arrows 10 indicated. Accordingly, the circuit board extends 2 transverse to the flow direction, wherein the flow direction of the substantially unpopulated side of the circuit board 2 or from the populated side of the circuit board 2 can take place. Accordingly, the heater will 1 used in a flow channel which is formed so that the circuit board 2 is flowed through.

To flow through the circuit board 2 are executed in this a variety of breakthroughs. 2 shows a part of the circuit board 2 in the area of a PTC block 4 in a view from the left on the heater 1 according to 1 , You can see an eruption of the circuit board 2 with a breakthrough 12 which is designed in this embodiment as a circular recess or bore. In the area of this breakthrough 12 is a PTC resistor element, hereinafter PTC device 4 called, on the circuit board 2 arranged so that this from the fluid flow 10 , which in the representation according to 2 runs perpendicular to the plane, is flowed around. The flow direction, as mentioned above, can be done from above in the direction of view, in which case first the PTC module 4 is flowed around and the fluid flow then through the breakthrough 12 goes through it. In this case, then the PTC module is located upstream of the breakthrough 12 , However, it is also possible to reverse the flow direction, so first the breakthrough 12 is passed through and only then to the downstream of the breakthrough 12 located PTC module 4 meets.

It is also possible to arrange the printed circuit board obliquely or even parallel to the air flow.

It is not necessary that every breakthrough 12 a PTC block is assigned - the number of breakthroughs 12 and the PTC building blocks 4 can be quite different. In practice, the number and shape and the relative arrangement of the apertures 12 be designed so that a sufficient heat transfer from the PTC components 4 on the fluid flow 10 is guaranteed. Of course, instead of the circular breakthroughs 12 Other geometries, such as elongated holes, elliptical eruptions, irregular shaped breakthroughs, etc. are used, so that sufficient leeway remains to optimize the flow resistance and heat transfer.

3 shows an embodiment of a circuit board according to the invention 2 that with three different recess patterns 14 . 16 . 18 is executed. These recesses are - as described above - in terms of flow resistance, on the best possible heat transfer and also on the contacting of the components 4 . 8th optimized in the SMD process. So is the recess pattern 14 a plurality of rows of openings next to each other 12 provided, wherein the openings are arranged in alignment in the vertical and horizontal directions in each case. When recess pattern 16 are the breakthroughs 12 arranged in adjacent rows offset from each other.

The recess pattern 18 shows an embodiment in which the breakthroughs 12 similar to the recess pattern 14 are arranged in alignment in the horizontal and vertical directions to each other, however, wherein the horizontal distance h is greater than the vertical distance v. Of course, other, virtually any recess pattern can be provided, the geometry of the apertures can be quite different. As mentioned earlier, it is also not required that any of the breakthroughs 12 a PTC module 4 or an electronic component 8th assigned.

At the in 1 illustrated embodiment is also the controller 6 arranged in the fluid flow, so that the components 8th be cooled. In principle, however, it is also possible, for example in the heating of conductive fluids, to form the control in a sealed manner, so that it does not come into direct contact with the fluid flow.

The advantages of the system described above are on the one hand in a cost-effective design, on the other hand allows the construction of the circuit board 2 a simple and flexible design of the heat transfer by design of the openings 12 and their relative positioning to each other and to the heating elements.

The performance of the heater can be flexible by different placement of the circuit board 2 be adapted to different requirements in the SMD process.

The connection to the controller 6 is very simple because the PCB carries both the heating elements and the controller. This is accompanied by optimized cooling of the coupled electronics.

However, the electronics do not have to be connected to the PCB 2 can be arranged, but in principle, similar to the prior art described above, be accommodated in a separate housing on a separate board.

The recess pattern is arranged so that the fluid flow is controlled in a controlled manner and that individual areas of the printed circuit board flow through more or less and thus a temperature distribution in the fluid flow can be adjusted.

Disclosed is a heating device for a fluid flow and a printed circuit board for such a heater in which heating elements are arranged on the circuit board, which in turn has openings for the fluid flow.

LIST OF REFERENCE NUMBERS

1

heater

2

circuit board

4

PTC resistive element

6

control

8th

module

10

fluid flow

12

breakthrough

14

recess pattern

16

recess pattern

18

recess pattern

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 1036930 B1 [0003]
• EP 0350528 B1 [0004]
• DE 102009033988 A1 [0005]

Claims (16)

Heating device for a fluid flow, with at least one heating element ( 4 ), which in the fluid stream ( 10 ) is arranged and emits heat when flowing around it, characterized in that the at least one heating element ( 4 ) on a printed circuit board ( 2 ) is arranged and contactable via these, the breakthroughs ( 12 ) for the fluid, wherein these are formed such that the heating element ( 4 ) is flowed around directly or indirectly. Heating device according to claim 1, wherein the breakthroughs ( 12 ) as a recess pattern ( 14 . 16 . 18 ) are executed. Heating device according to claim 2, wherein a plurality of different recess patterns ( 14 . 16 . 18 ) on the printed circuit board ( 2 ) are formed. Heating device according to one of the preceding claims, wherein the printed circuit board ( 2 ) by SMD technology with the heating elements ( 4 ) is equipped. Heating device according to one of the preceding claims, wherein the heating element ( 4 ) upstream or downstream of the respective breakthrough ( 12 ) is arranged. Heating device according to one of the preceding claims, wherein the breakthrough ( 12 ) is designed as a bore, slot or the like. Heating device according to one of the preceding claims, wherein a plurality of heating elements ( 4 ) with different characteristics, characteristic are provided. Heating device according to one of the preceding claims, wherein an electronic control also on the circuit board ( 2 ) is trained. Heating device according to claim 8, wherein the controller ( 6 ) at least in sections in the fluid stream ( 10 ) is positioned. Heating device according to one of the preceding claims, wherein the fluid is gaseous, preferably air. Heating device according to one of the preceding claims, wherein the printed circuit board ( 2 ) is positioned approximately perpendicular to the flow direction. Heating device according to one of the preceding claims, wherein the printed circuit board ( 2 ) in sections in the fluid stream ( 10 ) is arranged. Heating device according to one of the preceding claims, wherein the at least one heating element is a PTC resistance element ( 4 ). Circuit board for a heating device, in particular according to one of the preceding claims, wherein the printed circuit board ( 2 ) Heating elements ( 4 ) and with a large number of breakthroughs ( 12 ) carried out in a fluid stream ( 10 ) are arranged. Heating device according to claim 14, wherein the breakthroughs ( 12 ) in a recess pattern or in a plurality of recess patterns ( 14 . 16 . 18 ) are arranged. Printed circuit board according to claim 15, wherein the number of heating elements ( 4 ) and breakthroughs ( 12 ) is different.

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