EP3011803B1 - Heating device - Google Patents

Description

Technical field

The invention relates to a heating device with a housing with a fluid channel arranged therein with a fluid inlet and a fluid outlet, an element generating an alternating magnetic field being provided in the housing, at least one metallic surface heating element being provided which can be heated by the alternating magnetic field, wherein the at least one surface heating element is arranged in the fluid channel.

State of the art

Heaters are known in the art. There are air-side heating devices that have so-called PTC heating elements that are energized electrically and thereby heat up. The heat is transferred to the air flowing through air-side fins that are in contact with the PTC elements. However, these heating devices have a fundamentally different structure than is necessary for liquid media.

Heating devices for liquid media are provided with a closed housing, which are formed with a fluid channel with a fluid inlet and a fluid outlet, a heating element projecting into the housing and being heated with a PTC element.

These heating devices for liquid media have the disadvantage that the heat is generated in a different area than in the fluid channel through which the liquid medium that is to be heated flows. As a result, delayed heating is achieved due to the existing contact resistance, which is to be regarded as disadvantageous.
Inductive heaters for liquid media are already out of the WO 2009/050631 A or from the US 2,407,562 previously known.

Presentation of the invention, task, solution, advantages

It is therefore the object of the present invention to provide a heating device which is suitable for heating a fluid, the heated elements being flowed over directly by the fluid to be heated. In addition, the heating device should be as simple as possible and inexpensive.

The object of the present invention is achieved by a heating device with the features of claim 1.

The invention relates to a heating device with a housing with a fluid channel arranged therein with a fluid inlet and a fluid outlet, an element generating an alternating magnetic field being provided in the housing, at least one metallic surface heating element being provided which can be heated by the alternating magnetic field, wherein the at least one surface heating element is arranged in the fluid channel, the element generating the alternating magnetic field being formed by a hollow cylindrical coil which can be operated with an alternating voltage, the coil being separated from the fluid channel in a fluid-tight manner, the coil being arranged in a coil housing , which can be inserted into the housing, the coil housing being thermally conductive, and wherein the housing fluid at a first of its axial end regions through a first cover and at a second of its axial end regions through a second cover is tightly closable and the first lid has an annular circumferential groove into which the coil housing can be inserted.

A fluid-tight separation of the coil from the fluid flowing through the heating device is particularly advantageous since a short circuit can be prevented in this way. In addition, the coil is not exposed to any corrosive influences which could damage the coil.

A thermally conductive coil housing is advantageous, since this promotes the removal of heat from the coil onto the fluid, whereby more effective cooling of the coil can be achieved and at the same time improved heating of the fluid.

A housing which can be closed in a fluid-tight manner at a first of its axial end regions by a first cover and at a second of its axial end regions by a second cover ensures a functional fluid circuit within the heating device.

An annular circumferential groove, which is modeled on the coil housing, is advantageous since it forms a receptacle for the coil housing, as a result of which the coil housing can be securely positioned in the heating device.

Furthermore, it is preferable if the coil housing is formed by a cylindrical hollow body, the cylindrical hollow body being formed in one piece or from two hollow cylindrical elements of different diameters.

The coil housing is advantageously adapted to the design of the coil and / or the design of the rest of the heating device. This enables a compact design of the heating device.

It is also expedient if the coil is arranged in an intermediate space between the two hollow cylindrical elements of different diameters.

This enables the coil to be positioned in an area through which the fluid does not flow.

In addition, it is advantageous if the coil housing can be flowed around by a fluid on a radially inwardly directed lateral surface and / or on a radially outwardly directed lateral surface.

A direct flow of fluid over the coil housing is advantageous since the heat of the coil can be dissipated particularly well.

It can also be advantageous if the coil housing and the first cover are made in one piece, with electrical contacting of the coil being integrated in the first cover.

A one-piece design, for example from a common injection molded part, is particularly advantageous since the assembly of the coil in the heating device is considerably simplified. In addition, the electrical contacting of the coil can then take place through a channel or region integrated in the cover, which increases the mechanical robustness of the electrical contacting and furthermore simplifies assembly.

In addition, it is preferable if the first cover and / or the second cover and / or the coil housing is made of a plastic, the respective cover having shielding elements for shielding the alternating magnetic field.

Manufacturing the cover or the coil housing from plastic is particularly advantageous in order to achieve the most cost-effective production possible. In the case of a cover made of plastic, this can contain shielding elements which limit an unwanted propagation of the magnetic alternating field through the cover. This is necessary to reduce the negative effects of the alternating magnetic field on adjacent electrical or metallic components or completely prevent it. A possible shielding element could represent a ferritic sheet which is attached to an inner surface or an outer surface of the cover. Alternatively, such a ferritic sheet can also be cast into the lid.

According to a particularly advantageous development of the invention, it can be provided that the coil housing can be filled with a medium by means of which a fluid-tight seal of the coil housing can be produced and / or the thermal conductivity in the coil housing can be increased. This also serves to avoid short circuits and to improve the thermal management of the heating device.

In addition, it is expedient if the coil housing has swirl elements and / or turbulence elements on at least one of its jacket surfaces around which a fluid can flow.

In this way, the fluid flow within the heating device can be positively influenced. In particular, better mixing of the fluid can be achieved, which can lead to a more homogeneous temperature distribution within the heating device.

Furthermore, it is preferable if the coil housing and / or the coil has a temperature sensor. This is advantageous for determining the temperature of the coil in order to be able to prevent overloading, if necessary.

It is also advantageous if a temperature sensor is arranged in an area through which the fluid flows. This is advantageous in order to be able to reliably detect the temperature level of the fluid.

Furthermore, it can be particularly advantageous if the hydraulic diameter of at least one area through which the fluid flows can be changed by introducing a displacement body.

This allows the flow through the heating device to be optimized, which can contribute to greater performance of the heating device.

It is also advantageous if the surface heating element can be flowed with on one side or on both sides by a fluid.

The surface heating element is preferably in direct contact with the fluid flowing through the fluid channel. This ensures good and rapid heating of the fluid.

Furthermore, it can be particularly advantageous if a fluid can flow through the surface heating element on both sides, the direction of flow of the fluid on one side of the surface heating element being the same or opposite to the flow direction on the other side of the surface heating element. As a result, the fluid is first routed past one side and then the other side of the surface heating element. This increases the effectiveness of the heating.

A preferred exemplary embodiment is characterized in that the element generating an alternating magnetic field is an essentially hollow cylindrical element.

It is also preferable if the surface heating element is an essentially hollow cylindrical element.

Furthermore, it is preferable if the element generating an alternating magnetic field is a hollow cylindrical element, at least one surface heating element being arranged radially inside and / or outside the hollow cylindrical element generating the alternating magnetic field. This creates a space-saving heater.

It is also preferable if one or more hollow cylindrical surface heating elements are arranged radially inside and outside the hollow cylindrical element generating an alternating magnetic field. This can also increase the heat output.

In addition, it can be provided that the element generating an alternating magnetic field is an essentially hollow cylindrical coil.

It is also advantageous if the control unit is connected to the housing or integrated into it.

In addition, it can be advantageous if the housing consists of a material that absorbs magnetic fields or is non-transparent for alternating magnetic fields.

It is also expedient if the wall consists of a magnetic field transparent material.

Advantageous developments of the present invention are described in the subclaims and in the following description of the figures.

Brief description of the drawings

Fig. 1

eine perspektivische Ansicht einer Heizvorrichtung mit einer integrierten Steuereinheit,

Fig. 2

eine Schnittansicht der Heizvorrichtung gemäß Fig. 1, und

Fig. 3

eine Explosionsdarstellung der Heizvorrichtung gemäß den Fig. 1 und 2.

The invention is explained in detail below using exemplary embodiments with reference to the drawings. The drawings show:

Fig. 1

1 shows a perspective view of a heating device with an integrated control unit,

Fig. 2

a sectional view of the heater according to Fig. 1 , and

Fig. 3

an exploded view of the heater according to the 1 and 2 ,

Preferred embodiment of the invention

The Fig. 1 shows a perspective view of a heating device 1. The heating device 1 has a housing 3 to which a control unit 2 is connected. The control unit 2 is fastened, for example, to the housing 3 via screw connections. The housing 3 forms a cylindrical interior, in which the components of the heating device 1 are integrated. At the axial end regions of the housing 3, covers 4, 5 are provided which close the housing 3 at the end. The cover 4 has a fluid connection 6 and a fluid connection 7, which, depending on the direction of flow within the heating device 1, can each be used as a fluid inlet or as a fluid outlet.

The Fig. 2 shows a sectional view through which in Fig. 1 shown heating device 1. In the upper area of the Fig. 2 The control unit 2 is shown, which will not be discussed in more detail below.

Arranged in the interior of the housing 3 is a coil housing 9, which is formed from two cylindrical hollow bodies 10, 11. A coil 8 is arranged within the coil housing 9. This coil 8 forms a hollow cylindrical body which is formed from a winding of electrically conductive material.

The coil 8 is connected to the control unit 2 via an electrical contact 12. For this purpose, a connection area 13 is provided outside the housing 3, through which the electrical contact 12 can be guided into the control unit 2.

The coil housing 9, which is formed by the two cylindrical hollow bodies 10, 11, can have a medium in its interior in addition to the coil 9, which, on the one hand, encloses the coil 8 in a fluid-tight manner inside the coil housing 9 and, on the other hand, increases the thermal conductivity within the coil housing 9.

The two cylindrical hollow bodies 10, 11 have different diameters, so that inserting the two cylindrical hollow bodies 10, 11 into one another results in a cavity between the cylindrical hollow bodies 10, 11, which forms the receiving area for the coil 8.

In the center of the coil housing 9 there is a tube 18 which forms a channel 14 through which a fluid can flow. The channel 14 is in direct fluid communication with the fluid connection 6.

In Fig. 2 the fluid connection 6 is designed as a fluid inflow. A fluid can accordingly flow through the fluid connection 6 along the channel 14 in the tube 18 and flow at the end region of the tube 18 facing away from the fluid connection 6 into an area within the cylindrical hollow body 11 of the coil housing 9.

The tube 18 is plugged onto a shoulder which is attached to the inside of the cover 4 or to the fluid connection 6 and is connected there to the latter. The end region of the tube 18 facing away from the fluid connection 6 is spaced apart from the cover 5 such that there is an air gap between the tube 18 and the cover 5, through which a fluid forms in the channel 15, which is formed between the tube 18 and the cylindrical hollow body 11 is, can flow in. The fluid then flows through the channel 15 to the cover 4. Between the coil housing 9 and the cover 4, an air gap is provided, through which the fluid can finally flow into a channel 16, which is between the coil housing and a surface heating element 19, which also as hollow cylindrical body is formed, is formed.

The fluid can then flow again in the direction of the cover 5. An air gap is also provided between the surface heating element 19 and the cover 5 which the fluid can be redirected again between the surface heating element 19 and a housing wall of the housing 3 can flow again in the direction of the cover 4. A further surface heating element 20 can be provided between the surface heating element 19 and the housing wall. This surface heating element 20 divides the channel 17 between the surface heating element 19 and the housing wall of the housing 3 into sub-channels.

Via radially arranged openings in the cover 4, the fluid can finally via the in Fig. 2 Flowing fluid connection 7, not shown, out of the heating device 1.

The coil housing 9 is arranged in the heating device such that a fluid can flow around it on both sides. In this way, the heat generated within the coil 8 can be transported away by the fluid and can additionally be generated for a heating effect for the fluid.

Surface expansion elements such as swirl elements or turbulence elements can advantageously be provided on the outer surfaces of the coil housing 9 facing the fluid. In this way, the flow of a fluid can be positively influenced in such a way that heat transfer between the surface heating elements within the heating device 1 and the fluid is improved.

The elements shown in the heating device 1, such as the tube 18, the surface heating element 19 or the surface heating element 20, which consist of a metallic material, can be heated due to an induction effect. The heat can be transferred to the fluid flowing around the elements, whereby the fluid is heated.

The coil 8 is preferably provided with a current source via the electrical contacts 12, which supplies an alternating voltage to the coil 8. In this way, an alternating magnetic field can be generated, which can lead to heating of the metallic elements, such as the tube 18 and the surface heating elements 19 and 20.

The Fig. 3 shows an exploded view of the heating device 1 as already shown in FIG 1 and 2 was shown. In Fig. 3 it can be seen in particular how the individual elements of the heating device 1 are arranged one inside the other. Thus, the fluid connections 6 and 7 can be inserted into openings in the cover 4 and inserted into the housing 2 with the tube 18 or the surface heating element 19 and a surface heating element 20. The coil housing 9 and the coil 8 with their electrical contacts 12 can be inserted into the housing 2 from the opposite side, as it were. On the top of the housing 3, the control unit 2 is provided, which is provided for controlling the coil 8.

The design of the coil housing 9 can ensure that the coil 8 is completely separated from the fluid flowing through the heating device 1. An electrical short circuit can be avoided in this way. Furthermore, by integrating the coil 8 and the coil housing 9, which is surrounded by fluid, an advantageous heat transfer from the coil to the fluid is possible.

The in the 1 to 3 The exemplary embodiments shown are exemplary. In particular with regard to the dimensions of the elements, the geometric design of the individual elements or the arrangement of the elements with respect to one another 1 to 3 not restrictive in nature.

Claims (11)

1. A heating device (1) having a housing (3) with, arranged therein, a fluid passage having a fluid inlet (6, 7) and a fluid outlet (6, 7), wherein an element generating an alternating magnetic field is provided in the housing (3), wherein furthermore there is provided at least one metallic areal heating element (18, 19, 20) which can be heated by means of the alternating magnetic field, wherein the at least one areal heating element (18, 19, 20) is arranged in the fluid passage, wherein the element generating the alternating magnetic field is formed by a hollow-cylindrical coil (8) that can be operated with an AC voltage, wherein the coil (8) is separated from the fluid passage in a fluid-tight manner, wherein the coil (8) is arranged in a coil housing (9) that can be inserted into the housing (3), wherein the coil housing (9) is thermally conductive, characterised in that the housing (3) can be closed in a fluid-tight manner at a first one of its axial end regions by a first cover (4, 5) and at a second one of its axial end regions by a second cover (4, 5), and wherein the first cover (5) has an annularly circumferential groove into which the coil housing (9) can be inserted.
2. The heating device (1) as claimed in claim 1, characterised in that the coil housing (9) is formed by a cylindrical hollow body, wherein the cylindrical hollow body is formed in one piece or from two hollow-cylindrical elements (10, 11) of different diameters.
3. The heating device (1) as claimed in claim 2, characterised in that the coil (8) is arranged in an interspace between the two hollow-cylindrical elements (10, 11) of different diameters.
4. The heating device (1) as claimed in one of the preceding claims, characterised in that a fluid can be made to flow over a radially inward-oriented lateral surface and/or a radially outward-oriented lateral surface of the coil housing (9).
5. The heating device (1) as claimed in one of claims 1 to 4, characterised in that the coil housing (9) and the first cover (5) are made in one piece, wherein an electrical contact with the coil (8) is integrated into the first cover (5).
6. The heating device (1) as claimed in one of the preceding claims, characterised in that the first cover (5) and/or the second cover (4) and/or the coil housing (9) are made of a plastic, wherein the respective cover (4, 5) has shielding elements for shielding the alternating magnetic field.
7. The heating device (1) as claimed in one of the preceding claims, characterised in that the coil housing (9) can be filled with a medium by means of which it is possible to seal the coil housing (9) in a fluid-tight manner and/or to raise the thermal conductivity within the coil housing (9).
8. The heating device (1) as claimed in one of the preceding claims, characterised in that the coil housing (9) has, on at least one of its lateral surfaces over which a fluid can be made to flow, swirl elements and/or turbulence elements.
9. The heating device (1) as claimed in one of the preceding claims, characterised in that the coil housing (9) and/or the coil (8) has a temperature sensor.
10. The heating device (1) as claimed in one of the preceding claims, characterised in that a temperature sensor is arranged in a region through which the fluid is made to flow.
11. The heating device (1) as claimed in one of the preceding claims, characterised in that the hydraulic diameter of at least one region through which the fluid is made to flow can be changed by introducing a displacement body.

Images