KR100484730B1 - An electric heating device, especially for use in motor vehicles - Google Patents

Abstract

The present invention relates to an electric heating device which can be used particularly suitably as a heating device for automobiles. A plurality of heating elements, each of which is layered to form a heating block, form a structural unit with the control device. For this purpose the control device is mounted on a horizontal bar of the frame in which the heating elements are supported together. The air to be heated is ventilated through heating blocks as well as through- windows provided in the horizontal bar past cooling elements respectively connected to the power supply electronics of the control device.

Description

Electric heating device for automobiles {AN ELECTRIC HEATING DEVICE, ESPECIALLY FOR USE IN MOTOR VEHICLES}

The present invention relates to an electric heating device (heater) for air heating which is particularly suitable for use as an auxiliary electric heating device in automobiles.

In automobiles, a heating device (heater) or a radiator is mainly used to heat a vehicle or an engine. Also, they are used when the engine is started unless the engine provides sufficient heat energy. On the one hand, it is necessary to use such a heating device, especially in an automobile having an internal combustion engine with optimized fuel consumption.

However, the use of such a heating device is not limited to the automotive field. Such heating devices are also suitable for use for a wide variety of other purposes, for example in household equipment (indoor air conditioning equipment), industrial plants and the like.

EP-A2-0 901 311 discloses an electric heating means for automobiles. The disclosed heating device has a plurality of heating elements configured to form one heating block. The control unit and the heating block for regulating the heating elements are supported in a common frame. In this way, the control unit forms one component unit with the heating block supported on the frame. The control device includes a power supply electronics having electronic switches provided with coolers. The control device is arranged such that a major part of the airflow to be heated flows through the heating block and the boundary of the airflow is supplied to the control device for cooling purposes.

This known heating device is disadvantageous as long as the air flow flowing onto the control device reduces the overall efficiency of the heating power. The part of the airflow to be heated through the heating block and the part of the air flowing through the control device have different output temperatures. The output temperature of the air stream supplied to the controller is significantly lower than the temperature of the main air stream. This results in particularly inhomogeneous air release temperatures. In addition, the heater will be even more ineffective when low temperature air flows in.

Accordingly, an object of the present invention is to provide an electric heating device that can be more effective heating.

The object of the invention described above is achieved by the characteristic device described in claim 1.

According to the invention, the air to be heated is not supplied to the controller as a whole. However, the amount of air passing through used to cool the power supply can be controlled through an open window. In this way, it is possible to adapt to the amount of air passing through the heating block, and the amount of air in both cases will have substantially the same output temperature. In addition, using this method, the efficiency of the entire heater will not be diminished by the air flow being classified to cool the control.

According to a preferred embodiment of the present invention, means for influencing airflow are provided in the spaces between the openings opposite each other. In this way, the airflow is provided to be optimally supplied to the cooling elements of the power supply so that maximum possible heating to the cooling airflow is achieved. A particularly preferred variant can be achieved by U-shaped cooling elements, in which case it is arranged to provide auxiliary air guiding elements which protrude between the legs of the U-shaped cooling elements.

Cooling air can be further heated as it is directed over the components of the control. For this purpose, the circuit board of the control device is preferably mounted only on one side thereof. In this way it is possible to supply air to the components particularly simply. In addition, the arrangement of such components is particularly desirable for production engineering reasons.

According to a preferred embodiment of the present invention, the circuit board is disposed perpendicular to the plane of the frame. On the other hand, this kind of arrangement enables a simple air supply structure for the components. On the other hand, an electric heating device having a low depth structure can be implemented in this way.

The control device is fastened in a particularly simple manner, in which the electrical lugs of the heating elements protruding into the box of the horizontal bar are used for such fastening. For this purpose, spring elements auxiliary to the connecting means may be provided on the circuit board. This embodiment makes it possible to lead not only mechanical connections but also electrical connections, for example control currents for heating elements, with the aid of the same means. This has the effect of substantially reducing the amount of material required for the electric heating apparatus according to the present invention and the investment cost in the production process of the electric heating apparatus described above.

Further preferred embodiments of the present invention are described in a number of dependent claims which follow.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1A is a side view of the electric heating apparatus 1 according to the present invention, and FIG. 1B is a plan view of the electric heating apparatus 1. The electric heating device 1 has a heating block comprising a plurality of heating elements 2 arranged in layers or stacked on top of each other. Each heating element 2 consists of a resistive heating element and a radiator or heat guide plate arranged near the resistive heating element. The heating elements used as resistive heating elements are preferably positive temperature coefficients ('PTC') elements. The heating block comprising the heating element 2 is supported on the frame. The frame consists of horizontal bars 4 and 5 and opposite vertical bars 3 arranged at right angles to each other. The frame bars (components) are made of metal or plastic material.

The vertical bars 3 are designed in a substantially symmetrical structure, while the two horizontal bars 4 and 5 are different from each other in the embodiment shown in FIG.

Unlike the horizontal bar 4, the horizontal bar 5 is implemented in the form of a box with one side open. The opening of this box-shaped horizontal bar 5 is located on the side of the horizontal bar opposite the heating elements 2. The box is configured to insert a control to control the heat output of each heating element 2 by controlling the current supplied to the heating elements 2. The opening of the box-shaped horizontal bar 5 is closed by means of a plug-on or clip-on after insertion of the control circuit.

After insertion, the circuit board 10 of the control device is preferably arranged at right angles to the plane of the frame, but a parallel arrangement is also possible (not shown).

Heater 1 is supplied with current supplied via two connecting pins 8. These connecting pins are implemented to easily guide the required heating current. In the embodiment shown in Fig. 1, the connecting pin 8 is projected on the side where the box-shaped horizontal bar 5 is open.

On the same side another plug base (base) for controlling the control device is provided, which is not shown in FIG.

The horizontal bar 5 has a plurality of openings 7 on the side located in the plane of the frame. This aperture is arranged to be located on the airflow to be heated. Cooling elements 6 are arranged between the opposing openings 7, which are configured to belong to the power supply electronics of the control circuit. When the heating device is operated, the air to be heated flows through the opening window as well as the heating block consisting of the heating elements 2.

The amount of air flowing through the cooling elements 6 can be determined by selecting the size of the aperture 7. According to the present invention, the flow rate of air is adjusted to be as small as possible the difference in temperature between the air flowing through the heating block and the air flowing through the cooling elements 6. If the temperature of the air flowing through the aperture 7 approaches the temperature of the air flowing through the heating block as close as possible, the heating device will be operated at the highest thermal efficiency possible.

2 is a detailed view of the control device arranged in the box-shaped horizontal bar. The circuit board 10 is provided thereon with a control element 12 in addition to the power electronics. The control element 12 determines the amount of current to be delivered to each associated heating element 2 by the power electronics 11, in particular the power transistors. The amount of current is supplied to the controller from one of the connecting pins 8 via the conductive rail 13. The output of the power transistor 11 is firmly soldered to the circuit board 10 and is also connected to the spring elements 14 associated with this transistor.

The spring elements 14 are arranged on the circuit board to be connected to the connection lugs of the heating elements when the control device is attached to the horizontal bar 5. Such connecting lugs are shown in FIGS. 3 and 4.

In the embodiment shown, the connecting lugs 15 pass through the circuit board 10 of FIG. 2 and are inserted into the spring elements 14. Such a connection allows for rapid mechanical attachment of the circuit board to the control electronics of the frame. At the same time an electrical connection to each heating element is carried out.

The circuit board is provided with parts only on one side thereof. Depending on the number of heating stages, the circuit board is provided with power transistors 11 fixed horizontally thereto. In the disclosed embodiment three heating stages and thus three power transistors are provided. Each power transistor 11 is firmly soldered to the circuit board 10 at its output terminal.

One connecting lug is adapted to protrude beyond the transistor, which has one cooling element 6 fixed thereto. It would be advantageous to connect cooling element 6 to the heating element in a non-conductive manner.

The cooling element 6 is provided with a cooling fin disposed in a plane extending perpendicular to the circuit board. In the embodiment shown, the cooling fins are additionally arranged on the side on which nothing is mounted on the circuit board. Only one leg of the cooling element 6 is connected to the connecting lug of the transistor 11 to protrude to the side on which the objects on the circuit board are mounted and to consume the heat generated by the transistor. In the illustrated embodiment, the legs of the cooling elements connected to the transistors 11 are configured to protrude through the openings of the circuit board 10 to which the object of the circuit board 10 is attached. However, it may be possible to protrude beyond the edge of the circuit board so that the opening in the circuit board 10 is unnecessary.

Corresponding configurations of components comprising transistor 11, spring element 14 and cooling element 6 as described above are provided on the circuit board for each heating step.

3 shows a detailed configuration of a box-shaped horizontal bar 5 and a control device configured to be inserted into the horizontal bar. One side of the horizontal bar 5 is connected to a heating block having a vertical bar 3 and a heating element 2. The upper side of the horizontal bar 5 is provided with a window-shaped opening 7 through which air to be heated passes.

Three connecting lugs 15 and one connecting pin 8a are provided in the box-shaped horizontal bar 5 described above. This connecting pin represents an active connection for all heating elements 2. This figure also shows a perspective view of controller 5a which is additionally configured to be inserted into a box of horizontal bars 5. Control 5a is inserted into horizontal bar 5 on the side opposite the horizontal bar.

The lower surface of the circuit board 10 is disposed on one side of the control device 5a facing the horizontal bar 5. Three cooling elements 6 protrude beyond this circuit board 10. Each of these cooling elements or cooling plates is associated with one of the power transistors 11 in one heating stage.

A supplemental opening 7 is provided on one side of the horizontal bar 5 for each cooling element 6. This has the effect that each cooling element efficiently supplies airflow to it when the heater is operated.

Another connecting pin 8b is disposed on the side that is off the horizontal bar. This connecting pin serves as an electrical ground when current is supplied. The connecting pin 8b is connected to a conductive bar 13 which supplies a heating current to each heating step, shown in FIGS. 2 and 4. Each heating step draws approximately 40 amps of current from the amount of current supplied through its power transistor 11 via conductive rail 13.

4 is a more detailed perspective view of the control device configured to be inserted into the box-shaped horizontal bar 5 and the box-shaped opening of the horizontal bar.

In the upper region of FIG. 4, two opening windows 7 are shown on the surface of the horizontal bar 5. These opening windows are arranged such that when the control circuit is inserted into the horizontal bar 5 they are arranged above and below the cooling element 6.

The connecting lugs 15 of the heating element 2 are arranged in the box-like opening of the horizontal bar 5. Each connecting lug 15 is provided for each heating step.

In the lower region of FIG. 4, a control device is shown configured to be inserted into the horizontal bar 5. To show more clearly the structural design, only one power transistor is provided with cooling element 6. The configuration design of the remaining control circuits corresponds to the control circuits described in connection with FIG.

Figure 5 illustrates another embodiment of the present invention, in which Figures 5a, 5b and 5c show particularly different details from the previous embodiments described so far.

5A shows a somewhat modified design of horizontal bar 5. The arrangement of the aperture 7 corresponds to the embodiment described above. In order to more accurately affect the airflow, a wall is provided between the openings of the horizontal bar 5 to the extent possible to form a wall without disturbing the insertion of the control circuit in the horizontal bar 5. All intermediate spaces arranged above between these walls and the side facing the heating element are closed by additional walls 18. In this way, air is prevented from flowing around without purpose when the heater is operating.

5a and 5b show in detail how air is guided between the apertures 7. In order to guide the air more accurately, air guide element 17 is inserted in the area located between the opening windows 7. As can be seen in FIG. 5B, the Y-shaped spoiler element allows for better airflow around the cooling fins of the U-shaped cooling element 6. Each of the cooling fins of the cooling element 6 is arranged adjacent to the opening window 7.

In FIG. 5B, the circuit board 10 having the power transistor 11 is additionally shown.

5c shows a corresponding structural design of cooling element 6. In the above-described embodiment, the substantially U-shaped cooling element 6 is placed on the circuit board as a vertically U-shaped side, whereas the cooling element 6 according to the present embodiment has such a U-shaped configuration parallel to the circuit board 10. Arranged to have a lower side thereof. The Y-shaped air guide element 17 is thus arranged to protrude from the side of the horizontal bar facing the heating elements in the direction of the control device. When the cooling element 6 according to the first embodiment is used, supplementary air guide elements may be arranged on the horizontal area between the opening windows 7 facing each other.

In the embodiment shown in FIG. 5C the width b1 of one cooling fin is approximately 3 mm, while the distance b2 between the cooling fins is approximately 2.5 mm. The cooling body is preferably made from aluminum or copper.

6 and 7 another embodiment according to the invention is shown. This embodiment differs from the previous embodiment in particular in the structural design of the cooling bodies and the power transistors. The cooling body 20 according to this embodiment is connected in a different way to the power transistors in the previous embodiments, and the power transistor 11 has cooling vanes thereon, which carry the power transistor to one side. Configured to protrude out. The cooling bodies of the above-described embodiments are fixed to these cooling vanes. The cooling vanes of the power transistors are fixed to the circuit board by soldering. In the embodiment described next, the cooling body is connected to the transistor by clip connection means. 6 and 7 show that the cooling bodies 20 of this embodiment are designed with a special structure. In order to engage the clip 21, the cooling fins of the cooling body 20 are designed asymmetrically. For this purpose, the coolant, preferably U-shaped, has on its one side fewer fins than normal, thus allowing the clip 21 to engage. The clip preferably engages the power transistor 19 and the cooling body 20 from the outside to secure the cooling body 29 to the control device and the transistor 19 in this manner.

This embodiment is particularly suitable for SMD type power transistors. It is a characteristic of the structure of such an SMD type transistor that no cooling vane is provided to which the cooling body can be fixed. In order to be able to connect the cooling body to the lower surface of the power transistor 19, the circuit board is provided with a hole therein which preferably has a diameter of approximately 7.5 mm.

Therefore, the cooling body 20 is provided with the pin 20a in the lower side. In the embodiment shown this fin projects in a direction opposite to the direction of each cooling fin. The diameter of the pin 20a is preferably approximately 7 mm.

The pin 20a formed in the cooling body 20 is configured to protrude through a hole in the circuit board 10 and directly contacts the transistor 19.

This structural design is shown in detail in FIGS. 7A, 7B and 7C. FIG. 7A shows a top view of a circuit board 10 having a power transistor 11. The power transistor 11 is arranged at the boundary region of the circuit board 10 so that the clip 21 used to fix the cooling body 20 can be easily and firmly fixed. The circuit board may be provided with a recessed indentation at the position where the clip 21 engages the circuit board from above and below, so that the clip 21 does not require a circuit board 10 of larger depth. Preferably, the depth of this mark corresponds approximately to the thickness of clip 21 in this region. The transistor 19 is preferably arranged such that the connecting contact point 22 is directed toward the opposite edge of the circuit board.

FIG. 7B shows a side view and FIG. 7C shows a cross section along cut line A-A in FIG. 7B. FIG. 7C is geometrically adaptively arranged with each other in such a way as to ensure that the cooling body 20 and the spring 21 are fixed in the correct position at the optimum pressure.

As described above, an electric heating device suitable for use as an auxiliary heating device for a vehicle has been disclosed.

It is to be understood that the foregoing embodiments have been described by way of example only, and that modifications may be made without departing from the spirit of the invention. It is intended that the scope of the invention only be limited by the appended claims.

1a and 1b are a plan view and a side view of an electric heating apparatus according to the present invention.

FIG. 2 is a detailed view of a printed circuit board of a control device, showing the various components mounted on the circuit board. FIG.

3 is a detailed configuration diagram of a box-shaped horizontal bar and a control device configured to be inserted into the horizontal bar.

4 is a more detailed view of a box-shaped horizontal bar and a control configured to be inserted into the horizontal bar.

Figures 5a, 5b and 5c is a detailed configuration according to another embodiment of the present invention.

6 is a simplified detailed perspective view of a configuration for implementing another embodiment of a control device according to the present invention.

7a, 7b and 7c show various details of the structural design of the control device according to FIG. 6;

Claims (8)

A plurality of heating elements 2 configured to form one heating block, supported by rectangular frames 3, 4, 5, and A control device for controlling the heating elements 2, the control device forming a structural unit having a heating block supported on the frames 3, 4, 5, and a circuit board Power transistors 11 arranged on 10 are provided, wherein each of the power transistors 11 is configured to regulate the amount of power to be supplied to the respective heating elements 2. In the electric heating device for use as a device, And a power rail (13) for powering the respective power transistors (11) from a connecting pin (8b). 2. Electricity according to claim 1, characterized in that the output of each power transistor 11 is connected to the connection 14 assigned to the power transistor 11 and used for the heating elements 2 of one heating stage. Heating device. 3. Electric heating device according to claim 1 or 2, characterized in that the connecting pin (8b) is configured to protrude from the housing of the control device. The method of claim 1, The frame is defined by horizontal bars 4, 5 and opposing vertical bars 3 arranged at right angles to the vertical bars 4, 5, At least one of the horizontal bars 5 is embodied as a box which is open at its side and has a control inserted into it, Opening windows 7 are provided in the horizontal bar 5, and The cooling elements (6) of the power transistors (11) are characterized in that they are arranged between respective opposing openings (7) in the inserted condition of the control device. 2. The electric heating apparatus according to claim 1, wherein the circuit board (10) of the control device is mounted on only one side thereof. 6. The electric heating apparatus according to claim 4 or 5, wherein the circuit board (10) is arranged at right angles to the plane of the frame and its length is configured to substantially correspond to the length of the horizontal bar (5). . 5. The electrical device according to claim 4, wherein the control device is configured to be fixed to the horizontal bar 5 by electrical connecting lugs 15 protruding from the heating device 2 into the horizontal bar 5. Heating device. A spring element (14) for receiving the connecting lugs (15) is provided on the circuit board (10), the spring elements (14) complementing the connecting lugs (15). Electric heating device characterized in that the.