KR101158518B1 - Electric heating device - Google Patents

Abstract

The electric heating device has an open housing, in which multiple positive temperature coefficient-heating elements (18) are held with radiator elements (14) by clamping opposite to each other. The housing forms multiple separators. A heating rod (24) is included with radiator elements in individual separators and is held opposite to each other by clamping. The heating rod is made of positive temperature coefficient-heating element. An independent claim is also included for a housing for an electric heating device with a housing cover segment.

Description

ELECTRIC HEATING DEVICE {ELECTRIC HEATING DEVICE}

The present invention relates to an electric heating apparatus comprising a plurality of PTC elements and an open housing in which the radiator elements in contact with the PTC elements are kept in pretensioning contact with each other.

Such electric heating devices are generally known as vehicle PTC auxiliary heaters and are described, for example, in EP 1 564 503 B1 herein.

PTC heating elements have self-regulating properties. The electrical resistance increases with increasing temperature, which is advantageous when the PTC heating element is used to heat air in a vehicle as long as it prevents overheating of the electric heater. However, these self-regulating properties must effectively dissipate the heat generated by the PTC heating element. To this end, it is necessary to dissipate heat by the PTC element through in-plane heat conduction extending across the radiator element vertically. PTC elements, ie ceramic stones, are usually placed between two contact judgers. This arrangement forms the PTC heating element. The contact plate may be part of the radiator element. The radiator element is formed of a metal material having good thermal conductivity and releases heat first transmitted to the radiator element through heat conduction to the radiator element as ambient air.

The prior art discloses fundamentally different concepts regarding how to achieve the above good electrical and thermal contact between the heating element and the radiator element in contact therewith.

For example, EP 1 621 378 discloses a material-to-material bonding by means of an adhesive or solder between a PTC element and a contact plate and a radiator element called a wavy rib.

In the case of the prior art and EP 1 731 340 B1, which are the basis of the present application, a plurality of PTC heating elements with adjacent radiator elements are fixed to the housing by spring pretension. The spring supports a heating block consisting of a PTC heating element inside the housing and a radiator element in contact with the spring heating element. Corresponding structures are also disclosed in EP 1 564 503 above.

However, if the heating block is held in the housing by pretension, the spring element (s) must compensate for the substantial compression setting. Therefore, the spring must be able to apply the elastic pretension necessary for the reciprocating motion of the main spring. Therefore, it is usually necessary to use a spring consisting of a spring strip that occupies a particular space in the plane containing the heating block, thereby producing the spring force necessary to compensate for the tolerance in the required spring reciprocation.

On the other hand, it often causes problems by accommodating the heating block inside the housing by spring pretension. This is especially a problem when the elements of the heating block are first installed by spring pretension in the housing and only after that the housing is closed.

Applicant's EP 1 564 503 discloses a heating block held inside a housing by pretensioning of a spring tensioned by a displacement introduced into the housing while the housing is closed. According to this, the layer structure known in the art can be first mounted in the housing without pretension and then pretensioned during the closing of the housing, but the electrical heater shown here is adapted to the arbitrary structural dimensions for the heater. The disadvantage is that considerable effort is required.

In some cases, it is necessary to arrange the electric heating device in the installation space in the air conditioning module housing in the vehicle so as to occupy a relatively large space to cover the entire area where air flows. When effectively using the elements forming the heating block, this area may in some cases be larger than the area required to produce heating power. In this case, the heating block must have a structure that occupies a relatively large space, thereby significantly increasing the cost. The number of PTC elements provided in the heating block can be tailored to the desired heating power, but it is still necessary to fill the area through which the entire air flows through the housing with the PTC heating element and the radiator in contact with it.

This is improved with the solution disclosed in EP 1 621 378, where free spaces covered with plastic gratings are formed between individual heating rods, each of which comprises a PTC heating element and a radiator element in contact with it. The plastic grating is provided to prevent the bypass of the flow and to cause flow resistance in the housing so that in some cases the air to be heated impinges on the radiator element of the heating rod to heat up. The apparatus disclosed in EP 1 621 378 aims to enable good thermal homogenization. If higher heating power is required in the housing with the above dimensions, the plastic grating is replaced with each additional heating rod.

According to the principle of the solution disclosed in EP 1 731 340 B1, a plastic placeholder element is provided in a heating block, the whole of which is supported inside the housing by spring tension, so as to constitute an electric heating apparatus having the largest surface possible. Produced at a price. Like the solution presented in EP 1 621 378 B1, the solution presented here provides a placeholder which can be replaced by a heating PTC heating element and a radiator element in contact with it in the housing if higher heating power is desired.

It is an object of the present invention to provide an improved electric heating device. The present invention aims to provide a simple solution that can be produced at low cost by developing an electric heating device on which the PTC heating element and the radiator element in contact therewith are contacted with each other by pretension.

In order to solve this problem, the electric heating device underlying the present application is that the housing forms a plurality of compartments, each compartment accommodates each heating rod therein, each of the heating rods PTC heating It is further developed by the present invention in that it includes an element and a radiator element in contact with both sides of the PTC heating element, wherein the radiator element and the PTC heating element are in pretension contact with each other. The PTC heating element, in a manner known per se, comprises at least one PTC element, which PTC element is preferably received and clamped between two conductive metal sheet strips. The radiator element is in contact with each outer surface of the PTC heating element. The radiator element is exposed to an oil of air to be heated, wherein the air flows through an opening formed in the open housing. Each compartment of the housing is dimensioned such that a unit comprising only one heating rod, ie a PTC heating element and a radiator element in contact therewith, can be accommodated in the compartment. Each heating rod is respectively supported in a separate compartment. The elements forming the heating rod are supported in each compartment in pretension contact with each other.

The solution according to the invention provides the advantage that the spring pretensioning the elements in the compartment compensates for the small tolerances. This offers the possibility of associating each compartment with a relatively simple spring arrangement, which can be manufactured at low cost, allowing the elements supported in each compartment to be pretensioned with each other. Such spring arrangement may for example consist exclusively of plastic components. Suitable plastic components for tensioning PTC heating elements and radiator elements in contact with them in electrical heating devices used as vehicle auxiliary heaters are not actually known to date. The present invention first presents the possibility of using a suitable spring element composed of plastic material for tensioning the heat generating and heat dissipating layer in the housing. Spring elements made of plastic are usually distributed inside the housing and associated with each compartment. One spring element may tension elements of one heating rod in a single compartment with respect to each other. However, it is also possible to provide a spring element of plastic material which tensions the heating rod in two neighboring compartments with respect to each other.

Each compartment preferably associates with a spring element tensioning the element of the heating rod. However, at least one spring element is provided inside the housing in a spaced apart relationship with the housing edge.

According to one embodiment of the invention, the heating stage of the electric heating device is defined by each heating rod housed in a separate compartment. That is, each individual heating element contained within an individual compartment defines each heating stage. According to another embodiment of the invention, all the PTC heating elements and the radiator elements of the electrical heating device in contact therewith are joined together to form respective heating rods. Each of these heating rods is provided in a separate compartment. According to a preferred embodiment of the invention, the electric heating device is exclusively composed of a heating rod housed in each individual compartment.

According to another preferred embodiment of the present invention, an electric heating device having a relatively large dimension can be implemented at a relatively low manufacturing cost. Here, the neighboring compartment is closed by a housing cover which is secured to the lower housing component and exposes the spacer therebetween. The spacer is then formed by the lower housing component and connects the adjacent compartments to each other. According to this embodiment, it is only the lower housing component that defines the spacer. These spacers can adjust the arbitrary distance between neighboring compartments. The spacer itself is preferably not connected to the housing cover part. However, the spacer is wholly or partially exposed between the housing cover portions. In the cross section through the housing, two closures are obtained if the compartment is closed by the housing cover and one piece addition is provided if a spacer is provided between neighboring compartments. The housing cover part according to a preferred embodiment can be a housing cover segment and each of the housing cover segments is implemented separately and in connection with only one compartment for the closure. However, the housing cover portion may be provided in a uniformly formed housing cover defining a bridge in the area of the spacer only via a thin web, preferably a web provided on the boundary side. The bridge here connects the neighboring housing cover parts, preferably all the housing cover parts with one another. In any case, however, the material of the housing cover can be saved in the area of the spacer, so that the manufacturing cost of the housing, and consequently the manufacturing cost of the electric heating device, can be reduced. The spacer may have any thickness in the transverse direction, ie in the direction transverse to the longitudinal direction of the individual heating rods, so as to provide the largest heating device possible at low manufacturing costs.

In order to improve the strength, a preferred embodiment of the present invention proposes to implement a spacer so as to be displaced inward with respect to the bottom of the lower housing component when viewed in the thickness direction of the electric heating device. The spacer is preferably embodied as a relatively thin web that connects adjacent compartments to each other. According to an embodiment, a thin web may have a thickness of only 3% to 15% of the total thickness of the housing. Preferably the web is located on a layer corresponding to about half the height of the housing height.

In order to make the air resistance to the air passage area of the open housing more uniform, a preferred embodiment of the present invention proposes that the spacer has a vent. The vent has a flow resistance that approximately corresponds to the flow resistance of the heating rod. In any case, the resistance of the airflow in the flow path through the vents should not be much less than the resistance by neighboring heating rods, because otherwise there is a risk that most of the air does not heat up effectively and passes through the spacers. .

The present invention also proposes a housing for an electric heating device of the above type. The housing defines a lower housing component with compartments. The compartment houses therein at least one heating rod comprising a PTC heating element and a radiator element on both sides thereof and a spacer spaced apart and connected to each other. Such a housing is used to make an electrical heating device of this type occupying a relatively large space at a low cost. The housing and consequently the electric heating device can be manufactured in a material-saving manner and as a result can be manufactured at low cost.

According to another preferred embodiment of the invention, the housing comprises a housing cover portion covering a neighboring compartment. The housing cover portion is configured to be connected to the lower housing component and exposes the spacer defined by the lower housing component therebetween. Individual housing cover portions can be defined by individual housing cover segments. However, the housing cover segment may also be part of a uniform housing cover connected to the lower housing component, for example by a detent connection. An integral structure of the housing cover may be desirable to facilitate mounting. However, for the desired spring tensioning of the individual elements of the compartment, the latter is preferably produced by an element which creates spring tension, i.e., imparts spring pretension, only when installed within each plane of the radiator element and the PTC heating element. Should be considered. This type of structure is preferred for installing the radiator element and the PTC heating element in each compartment and pretensioning the element while closing the housing without first tensioning the element. However, this structure involves higher resistance, which must be overcome when attaching the housing cover and thus connects the housing cover with the detent projection to the lower housing component on the one hand and the spring element (s) on the other hand. Try to pretension. In this regard, it may be necessary to provide a plurality of lower cover segments that can be coupled to the lower housing component by applying intermediate low pressure. Preferably the spacer is positioned to be displaced inward with respect to the bottom of the lower housing component when viewed in the thickness direction of the housing. Therefore, the spacer is not located in the plane in which the bottom of the lower housing component extends. Preferably, in the vertical direction, the spacer is provided approximately in the center on the housing and in the form of a web connecting the two compartments together according to a preferred embodiment. For the reasons mentioned above with respect to the electric heating device, the spacer is preferably provided with a vent.

As mentioned above, the electric heating device preferably has a spring arrangement consisting exclusively of plastic material. According to a preferred embodiment of the invention the housing comprises an upper housing component and a lower housing component, the lower housing component comprising at least one support element protruding from the bottom of the lower housing component and the upper housing component being the support element. And a corresponding element for protruding from the lid surface of the upper housing component. The support element and the corresponding element are implemented such that when the housing is closed, the two elements cooperate with the spring element of plastic material. The spring element is tensioned between the support element for producing the elastically deformable component and the corresponding element and elastically stores this deformable component. This spring arrangement can be associated with a single compartment comprising a single heating rod. However, the above spring arrangement may also pretension the elements of the heating block inside the housing. The housing block here comprises a plurality of PTC heating elements and radiator elements in contact therewith.

According to one embodiment of the invention, the electric heating device has an open housing wherein at least one PTC heating element and a radiator element are supported by a pretend wire. The housing then includes a lower housing component and an upper housing component having openings therein, through which the medium colliding with the radiator element can flow. The lower housing component has at least one support element protruding from the bottom thereof. The upper housing component has a corresponding element for the support element and the corresponding element protrudes from the lid surface of the upper housing component. While closing the housing, the support element and the corresponding element cooperate with the spring element of plastic material. The spring element stores the deformable components that are tensioned between the support element and the corresponding element and thus manufactured.

This embodiment provides the possibility of individually forming and pretensioning the receiving space, in particular the receiving space for a single heating rod comprising the PTC heating element and each radiator element in contact with the sides of the PTC heating element. do. At this time, the pretension is applied by the spring element of the plastic material. Although plastic spring elements were deemed unsuitable for tensioning the heat generating and heat dissipating layers of an electric auxiliary heating apparatus of the object type, Applicants' experiments show that the heat generation in the housing, the accommodating space for the heat dissipating element, and the dimensions of these heat and heat dissipating elements It has been found that the required tensioning can also be caused by plastic spring elements if they fit well with each tolerance.

The spring tension here preferably occurs exclusively on closing of the housing. In closing, the support element and the corresponding element cooperate and thus cause deformation of the spring engagement, during which the elastically deformable component is produced in the spring element. In terms of the elasticity of the spring element, such deformable components are stored and thus the spring element is adapted to compensate for thermally coordinated dimensional changes and possible compression settings. The individual layers of the radiator element and the PTC heating element are reliably and permanently in contact with each other by the pretension of the spring.

According to another preferred embodiment of the invention, the spring element is defined by a plastic cord. The plastic cord extends in the longitudinal direction and alternates in the longitudinal direction of the plastic cord to be deformed by the provided support and the corresponding element to store the elastically deformable component. The support and the corresponding element are preferably arranged in an alternating mode such that the longitudinally adjacent corresponding element of the plastic cord first follows the support element. However, the support element and the corresponding element may partially overlap in the longitudinal direction. The direction considered in the longitudinal direction is the direction in which the individual layers of the heating stack or heating block extend, ie the longitudinal direction of the PTC heating element with elongated metal sheet strip. Preferably, three of the above elements are joined to each other to form respective groups for bending the spring elements in a predetermined position by alternating support points. This arrangement is contemplated such that the PTC element secured by the spring tension generates predominantly spring tension in the longitudinal portion provided inside the housing. In order to achieve the simplest possible structure, a single support element is preferably provided centered between two neighboring corresponding elements so that alternating bending of the plastic cord takes place by three support points. Wherein the middle of the support points is defined by the support element and the other two are defined by the corresponding element.

According to one embodiment of the invention, the plastic cord is formed by a plastic band inserted in the housing. The plastic bands can have different cross-sectional configurations. This can be a long, flat band. Alternatively, the plastic band may be implemented as a string having a circular or any other cross section. Such a band may be divided into segments and may extend only over a portion of the length of the housing.

It has been found that a sufficient degree of elastic tension can be generated even if the plastic band consists of soft elastic plastic elements. Materials that can be used as soft elastic plastic elements can be, for example, thermoplastic elastomers or silicones. Plastic bands should have high elasticity. As for the thermal resistance, natural rubber may be used as the soft elastic plastic material to form the plastic band. However, the plastic band does not need to consist exclusively of each soft elastic plastic material. It may also comprise a core, such as a core of fibrous material. Fillers may also be added.

According to an alternative embodiment, the plastic cord is integrally formed with the lower housing component and / or the upper housing component by injection molding. In order to manufacture such plastic cords, it has already been found sufficient by using the plastic materials normally used to implement plastic housings. The housing as a whole may be made of a homogeneous material by injection molding. However, injection molding may form plastic cords integrally with the housing, including some other components. Plastic cords made of a highly elastic plastic material may be placed as an insert in an injection molding die, for example used to form the lower housing component and / or the upper housing component. Thus, the plastic cord integrally formed with each housing component need not be made of the same material as the housing component.

Good tensioning of the PTC heating element and the radiator element in contact therewith may be achieved, for example, in that the plastic cord is provided at approximately half the height of the receiving space in the closed housing. The receiving space is defined between the lower housing component and the opposite inner surface of the upper housing component, ie between the bottom of the housing and the cover surface of the upper housing component. The lid face is the inner face of the upper housing component. The plastic cord is preferably provided at approximately half the height of the housing space and is preferably essentially confined to this area. Thus, the plastic cord preferably extends only above the central region of the height of the housing space and preferably to a height corresponding to 7-15% of the height of the receiving space. In this way, the spring pretension generated by the plastic cord can be used to effectively tension the PTC heating element and its radiator element.

According to a preferred embodiment of the invention, the upper housing component or the lower housing component has a contact element formed integrally therewith. The pretension generated by the spring element by this contact element is introduced into a layered structure comprising at least one PTC element and at least one radiator element. Thus, the contact element transmits the spring force to the layered structure. The contact element is pivotally supported relative to the integrally formed housing component. The pivot axis extends parallel to the longitudinal direction of the housing, ie parallel to the longitudinal direction of the PTC heating element. The pivot axis is preferably located near or in the bottom surface of the lower housing component or near or in the cover surface of the upper housing component. In any case, the contact element is preferably freely protruding from each surface portion of the upper housing component or the lower housing component so that pivotability about the pivot axis is prevented from connecting with the side wall of the upper housing component or the lower housing component. Do not.

According to a preferred embodiment of the invention, the contact element has an inclined sliding surface on the side facing away from the spring element. This sliding surface makes it easier to install the PTC heating element and the radiator element in the housing. In particular, by installing a heating rod, the contact element extends to a predetermined length in the direction of the spring element. The sliding surface terminates at approximately half the height of the housing space for transmitting the spring force by the contact protrusion. This contact protrusion is usually in contact with one of the radiator elements. In view of the above structure, the contact element is pretensioned to some extent in the direction of the support element, at which time the PTC heating element and the radiator element in contact therewith are introduced into the housing. The spring element, in particular located between the support element and the contact element, pushes the contact element against a neighboring radiator element, for example in a central area, so that the radiator element is pretensioned with respect to the PTC heating element and thus the other radiator element. The PTC heating element is pretensioned with respect to.

In order to easily introduce the plastic band into the housing, according to one embodiment of the invention, the dorsal part of the contact element facing away from the sliding surface is embodied to extend approximately perpendicular to the floor and the inclined surface of the support element facing the contact element is It is implemented to be inclined toward the contact element. This inclined configuration and the back of the contact element form a funnel-shaped tapered receiving means for the plastic band. This facilitates the insertion of the plastic band on the one hand and on the other hand sliding the inclined surface when inserted into the housing so that the plastic band approaches the back of the contact element (s) and thus accurately transmits the spring force to the radiator element. Located approximately in the middle.

The end position of the plastic band is reliably secured according to one embodiment of the present invention. The inclined surface here is coupled with a support for the plastic band extending approximately parallel with the bottom. This support serves as a contact surface for the plastic band and places it vertically in the housing space. The support also prevents the plastic spring, which is deformed due to compression in the direction of insertion of the corresponding element, from being displaced in the direction of the lower housing component and thus avoids the tension to be applied. The support may be included between two neighboring corresponding elements. However, according to one embodiment the support and the corresponding element may be partially or wholly covered with each other in the longitudinal direction of the housing.

According to another preferred embodiment of the present invention, a contact surface is provided for transferring the elastic deformation component to the PTC element. This contact surface is usually defined by the contact element. To deliver the elastic deformation component, the contact surface can be moved in the direction in which the tensioning is effective. The contact surface may preferably be effective only over a part of the height of the total receiving space. That is, for example, only a part of the height of the radiator element. The contact surface may be provided in the vertical direction at any position in the receiving space. However, the contact surface must be provided on the same level as the PTC element associated with it. It is not necessary for the contact surface to transfer the modifying component directly to the PTC element, but the modifying component may be indirectly transmitted to the PTC element via another layered layer, such as a metal sheet strip or radiator element provided between the contact surface and the PTC element. The use of contact surfaces and the provision of associated PTC elements on approximately the same layer is intended to transfer the spring forces generated by the springs to the PTC elements in the best possible way.

However, in the vertical direction of the housing, it is known to be advantageous when the contact surface and / or the PTC element is provided eccentrically near the air inlet side of the electric heating device. The air inlet side means the side into which the air to be heated enters the open housing. The PTC element is preferably located just below the cover which covers the upper housing component and the lower housing component respectively and has an opening provided therein for it. Such embodiments may be individually necessary in the present invention and may be implemented in conventional electric auxiliary heaters. In this case, each of the layer structure and the heating rod is supported by the pretension of the metal spring. It is also possible to arrange the PTC elements eccentrically in a positioning frame which is covered in whole or in part by opposing metal sheet strips. According to one embodiment, the PTC element contained within the housing may be suitable for use where the height is smaller than the radiator element associated with the PTC element, in which case the radiator element determines the height of the receiving space in the housing.

The eccentric mode of placement of the PTC element is achieved in particular by forming a support rib on the lower housing component or the upper housing component. The support ribs here are associated with at least one PTC element and extend at least section by section in the longitudinal direction of the housing. By this support, the PTC element is disposed close to the air inlet area. However, the support ribs preferably have the function of positioning the PTC element so as to be eccentrically positioned in the receiving space, as well as to reinforce the housing component, thereby extending longitudinally, preferably continuously. .

According to a preferred embodiment, the spring element preferably has a U-shaped configuration which opens with the corresponding element towards the bottom of the lower housing component. In such a configuration, preferably the spring element extending approximately parallel to the corresponding element defines a contact surface for contacting a neighboring radiator element which is contacted by pretension and applies a spring force to the heating rod. In addition to the two legs protruding towards the bottom of the lower housing component, the spring element preferably comprises a web that connects the fraud legs with each other and is provided between the cover surface and the height of half the height of the housing space with the housing closed. . Such a web functions as a spring web and is preferably bent in the direction of the housing cover, so that the web can be deformed to be bent upward in order to generate a spring tension.

According to one preferred embodiment of the invention, a spring leg extending approximately parallel to the corresponding element is connected to the housing cover in a material to material combination. The parallel mode of placement of the corresponding element and the spring leg is given in particular when the spring element has not been loaded, ie before the housing is assembled. The spring leg preferably extends perpendicular to the housing cover in this embodiment.

When the spring leg is formed integrally with the housing cover, it is preferably a corresponding element defining the contact element pivotable on and integral with the housing component. Here, the contact element preferably defines a contact surface for transferring the elastic deformation component to the PTC element. It is assumed here that the corresponding element deforms to at least a slight degree when the housing is closed and the contact surface is in contact with the radiator element, for example. However, the prominent deformation portion and its elastic storage are ensured by the spring leg and / or the web connecting the spring leg and the corresponding element.

According to one preferred embodiment of the invention, the support element defines a ramped pretensioning surface on which the spring element slides to generate an elastic deformation component during closing of the housing.

1A is a plan view of the electric heating apparatus according to the first embodiment,
1B is a view showing an electric heating device according to a modification of FIG. 1A,
2 is a cross-sectional view taken along line II-II of FIG. 1A;
3 is a cross-sectional view taken along the line III-III of FIG. 2,
4 is a side view of a spring means according to an alternative embodiment of FIGS. 2 and 3;
5 is a perspective view of a part of the spring means of FIG. 4, FIG.
6 shows the spring means shown in FIGS. 4 and 5 with the housing closed;
7 shows an upper housing part of another embodiment with spring means,
8 shows the spring means shown in FIG. 7 with the housing closed;
9 is a plan view schematically showing a part of a lower housing component of another embodiment of the present invention, and
10 is a cross-sectional view taken along the line XX of FIG. 9.

Further details and advantages of the present invention will become apparent from the following detailed description with reference to the drawings.

Referring to FIG. 1A, a plan view of the housing 2 is shown. The housing 2 comprises a lower housing component 4 and an upper housing component 6 connected to each other. In addition, the housing 2 comprises two covers extending in parallel, in FIG. 1A only the cover 8 formed by the upper housing component 6 is shown. The cover 8 includes a plurality of openings 10 formed therein to allow air to flow through the housing 2.

The longitudinal web 12 extends centrally and through the radiator element 14 through each opening 10. As shown in FIG. 2, the radiator element 14 covers the PTC heating element 16 located below the opening and generating heat. The PTC heating element 16 includes a plurality of PTC elements 18 arranged back and forth in the direction of the longitudinal web 12 and a metal sheet strip 20 in contact with both sides of the PTC elements. Opposing metal sheet strips 20 of the PTC heating element 16 are supplied with currents of different polarities. The selected metal sheet strip may extend in parallel over the housing 2 in a manner known per se to form a contact lug (see EP 1 564 503).

The PTC heating element 16 and the radiator element 14 abutting on both sides form a respective heating rod 24. The lower housing component 4 forms a compartment 26 for each heating rod 24.

As can be seen from the cross-sectional view of FIG. 2, within each compartment 26 a heating rod 24 is arranged, wherein the heating rod 24 is supported by the pretension of the spring and thus the heating as described in detail below. The individual layers of the rod 24, ie the radiator element 14, the PTC element 18, and the metal sheet strip 20 provided therebetween are brought into contact with each other by pretension and are thus produced by the PTC element 18. The heat can be transferred to the radiator element 14 with good thermal conductivity and the current can be reliably transferred from the metal sheet strip 20 to the PTC element 18. In the embodiment shown in FIGS. 1A-3, all metal sheet strips 20 pass out of the compartment 26, on the end face of each compartment, to form a plug contact.

Between the compartments 26 a spacer 30 is formed by the lower housing component 4. This spacer 30 acts as a bridge of the distance between the compartments 26 via the web 31 and is displaced inwards with respect to the outer housing face permitted by the cover 8 (see FIG. 2). In the region of the spacer 30 an upper housing component 6 provided after the manufacture of the housing cover has an opening therein. In the embodiment shown in FIG. 1A, the upper housing component 6 comprises a cross member 34 which is provided only at the boundary side and connects the housing cover part 32 to each other. At this time, each housing cover portion 32 covers each compartment 26. On most of the length of the housing 2, i.e. on the portion extending in the direction parallel to the radiator element 14 and the metal sheet strip 20, the spacer 30 is not covered by the housing cover portion 32 and thus is individually Between the compartments 26 the housing 2 is essentially implemented as a single layer housing. That is, it is implemented to include only the spacer 30. The cross member 34 is narrower than the length of the housing 2 and no more than 90% of the total length of the housing 2 between the individual compartments 26 is not covered by the cross member 34.

The web 31 of the spacer 30 has a plurality of ventilation holes 36 arranged back and forth in the longitudinal direction of the housing 2. The flow resistance of the airflow flowing through the housing 2 by the vent 36 becomes approximately the flow resistance by the individual radiator element 14 so that the total flow of air discharged from the air exhaust side of the housing 2 is Is saved. At this time, the total flow of the discharged air has a uniform temperature by mixing the air flow flowing through the opening 10 on the one hand and the air flow flowing through the vent 36 on the other hand.

FIG. 1B illustrates an alternative embodiment essentially corresponding to the embodiment described above with respect to FIG. 1A. The same components are given the same part numbers here. The difference between the embodiment of FIG. 1B and the embodiment of FIG. 1A is that in the embodiment of FIG. 1B the housing cover portion is an individual housing cover instead of the housing cover 6 comprising a plurality of housing cover portions 32 connected to form a unit. Is provided in the form of a segment 38. The housing cover segment 38 extends over the full length housing 2 and is fitted with an opening 40 formed on the transversal beam 42 formed by the lower housing component 4. The individual spacers 30 extend up to the transverse beam 42 in the longitudinal direction of the housing 2. Providing such a housing cover segment 38 forms the upper housing component 6 consisting of multiple pieces.

2 and 3 show spring means 44 which are configured in this embodiment so that only the outermost heating rod 24 is engaged. Spring means of the same or similar structure are adjacent to the heating rod 24 and / or two so that the ballistic pretensioning force by the spring means 44 pretensions the layers of neighboring heating rods 24 relative to one another. It can be added between heating rods.

The spring means 44 have a support element 46 formed on the lower housing component 4 and inclined at one end in the form of an inclined surface 48. Several support elements 46 are formed by the lower housing component 4 in the longitudinal direction of the housing 2. The lower housing component 4 also forms the fixing element 50. The fixing element 50 is then provided at regular intervals and the effective area of the fixing element 50 extends parallel to the effective area of the support element 46, ie at right angles to the bottom 52 of the lower housing component 4. do. The stationary element 50 is arranged to be displaced with respect to the support element 46. The stationary element 50 is located approximately centered between the neighboring support elements 46. The lower housing component 4 between the support element 46 and the fixing element 50 is provided with a spring strip 54 which forms a plastic cord in the sense of the invention. The spring strip 54 then extends over approximately the entire length of the housing 2. The spring strip 54 is slightly pretensioned between the stationary element 50 and the neighboring support element 46 and is therefore supported in the lower housing component 4.

On the lower housing component 4 is formed a spacer rib 56 protruding from the bottom 52. The spacer rib 56 spaces the PTC element 18 of the PTC heating element 16 in the longitudinal direction of the housing 2. The spacer ribs 56 extend over the entire height of the lower housing component 4 to form a contact surface for the upper housing component 6. The fastening element 50 is arranged approximately on the layer of the spacer rib 56 in the longitudinal direction of the housing 2. The fixing element 50 is not formed on the layer of the PTC element 18. In FIG. 2 the radiator element 14 constituting the outer radiator element abuts on the contact element 58, with the inner surface of the contact element 58 facing the radiator element 14 somewhat convex to form a linear contact surface 59. Done. At this time, the region of maximum thickness extends to about half the height of the receiving space 60 for the PTC element 18 formed by the housing (2).

The contact element 58 protrudes from the bottom 52 of the lower housing component 4. However, at its end it is not connected to the lower housing component 4 but slot 62 with respect to the bearing element 64 or the transverse beam 42 which projects vertically from the bottom of the housing and forms contact with the fixing element 50. Cut through). Because of this structure, the contact element 58 is rotatable about the floor about an axis extending parallel to the longitudinal direction of the housing 2.

The PTC element 18 is provided between the spacer ribs 56 protruding from the bottom 52 of the lower housing component 4 and positioned close to the transverse beam 42 and the border, or between adjacent spacer ribs 56. Are positioned on the supporting ribs 66. By this support rib 66, the PTC element 18 is accommodated in the receiving space 60 of the housing 2 at a predetermined distance from the bottom 52.

The upper housing component 6, consisting substantially of a cover, has a plurality of displacement elements 68. The displacement element 68 forms a corresponding element for the support element 46. The displacement element 68 is formed on the housing lid surface 67 facing the receiving space 60. This displacement element 68 protrudes approximately perpendicular to the housing cover portion 32. Referring to the cross section according to FIG. 2, the displacement element 68 is convexly formed at both sides thereof. The displacement element 68 is formed integrally with the upper housing component 6 and is provided between neighboring support elements 46 when viewed in the longitudinal direction of the housing 2.

As can be seen in the plan view of the open lower housing component 4 according to FIG. 3, a plurality of spring means 44 is provided in the longitudinal direction of the housing 2. Each spring means 44 is separated from each other by a fixing element 50 associated with a bearing element 64. Each of the spring means 44 comprises a displacement element 68 and a support element 46. The displacement element 68 extends over the contact element 58 and is limited to the length dimension of the contact element 58 and forms the corresponding element of the contact element 58. The support element 46 is associated with and alternates with the displacement element 68. The spring strip 54 extends generally in one piece through the entire length of the housing 2.

In order to tension the individual layers of the heating rod 24 supported in the compartment 26, the upper housing component 6 is applied to the lower housing component 4 so that the neighboring support elements 46 when the housing 2 is closed. Elastically bend the spring strip 54 between the < RTI ID = 0.0 > The resulting pretension of the spring is transmitted via the contact element 58 to the element of the heating rod 24. By the convex shape of the displacement element 68 and the contact element 58, the spring force is concentrated in the center region (in the vertical direction) of the receiving space, that is, the region where the PTC heating element 16 is located. The result is sufficient electrical contact between the PTC element 18 of the heating rod 24 and the metal sheet strip 20, and sufficient heat via the metal sheet strip 20 between the PTC element 18 and the radiator element 14. Generate contact.

The spring strip 54 may be a strip of plastic ash. Alternatively, spring steel strips may be inserted. However, in the case of the spring means 44 in which only one element of the heating rod 24 has to be pretensioned in one compartment 26 and its dimensions are exactly matched to the dimensions of the heating rod 24, the plastic spring element. It has been found that the spring force exerted by is sufficient to achieve good thermal and electrical contact between the PTC element 18 and the other elements of the heating rod 24.

4 to 6 show an alternative embodiment of the spring means indicated by reference numeral 70 of this embodiment.

The spring means 70, like the support element 46 of the above embodiment, protrudes from the bottom 52 of the lower housing component 4 and, as a corresponding element, a displacement protruding from the housing cover part 32. A support element 72 is provided to cooperate with element 74 to resiliently pretension the spring element formed by the silicon string 76 between two alternative support points.

To this end, the support element 72 has an inclined surface 78, and a funnel-shaped receiving space is formed for receiving the silicon string 76 through the inclined surface 78. Here, the receiving space is formed between the contact element 80 and the support element 72 in which the back portion 82 extends perpendicular to the bottom 52. In cross section, the contact element 80 has a shape corresponding to the shape of the contact element 58 and in addition to the dorsal portion extending perpendicular to the bottom 52, the shape of the central area is convex. This convex shape forms an inclined sliding surface 84 and the contact protrusion 86 cooperates with the neighboring radiator element at approximately half the height of the receiving space 60.

Each support element 72 is provided in the longitudinal direction of the silicon string 76 between adjacent contact elements 80 that are associated with each other. The displacement element 74 formed on the housing cover portion 32 is located on the layer of the contact element 80 when viewed in the longitudinal direction. A support 88 along the sliding surface 84 and extending substantially parallel to the bottom 52 and formed by the support element 72 is spaced vertically from the bottom 52. The silicon string 76, which is located here on the support 88, is located on the layer of the approximately contact protrusion 86 of the contact element 80.

In addition, the embodiment of the spring means 70 shown in FIGS. 4 to 6 tensions only one heating rod 24 which may not correspond to the heating rod 24 according to the embodiment, although not shown. . In addition, the PTC element 18 is arranged such that the PTC element 18 is located on the floor corresponding to half the height of the height of the receiving space (60).

For assembly, a heating rod 24 is first introduced into the compartment. In addition, a silicon string 76 is disposed on the support 88 such that a longitudinally extending silicon string 76 is positioned between the back of the contact element and the sliding surface 84 of the support element 72.

When the housing cover portion 32 is closed, the displacement element 74 acts against the silicon string 76 on the back portion 82 of the contact element 80. This has the effect that the silicon string 76 is elastically deformed between the supporting points alternated in the vertical direction of the receiving space 60. The width of the support element 72 may vary depending on the elasticity of the silicon string. The contact element 80 of the support element 72 may also overlap in the longitudinal direction or may be embodied as a continuous element in the region of the spring means 70.

6 and 7 show an alternative embodiment comprising plastic spring means 90. The plastic spring means 90 here comprise two U-shaped legs extending downwards. One of the two legs is indicated by reference numeral 92 and constitutes a corresponding element and has an inclined surface 74 which is slidable on the radiator element 14 and engages with the contact protrusion 96. The legs of this embodiment facing away from the radiator element 14 are referred to as spring elements 98 because these legs are formed integrally with the housing cover 32 by injection molding and store most of the elastically deformable component. to be. The two legs 92, 98 are connected to each other by the web 100. The lower housing component 4 shown in FIG. 7 is manufactured as an integral component by injection molding of plastics. Similar to the contact element 80 of the embodiment shown in FIGS. 4 to 6, one side of the housing cover portion 32 in which the longitudinal slot 102 faces the radiator element 14, ie the basis of the corresponding element 92. Is provided on the side. On the back of the corresponding element 92 facing away from the longitudinal slot 102, another longitudinal slot 104 is formed which extends to the web 100.

Referring to FIG. 8, which is a longitudinal cross section, a support element 106 is shown. The support element 106 is here associated with the spring element 98 on the side of the lower housing component 4. The support element 106 forms a sliding surface 108. Along the longitudinal direction of the housing 2 a plurality of spring means 90 is provided on the side of the upper housing component 6. The spring means 90 here have an associated support element 106. Also in this case, each spring means is preferably located on the layer of the PTC element 18 when viewed in the longitudinal direction.

For assembly, the element forming the heating rod 24 is first placed in the lower housing component 4. The heating rod 24 contained within the compartment 26 is pretensioned by attaching an upper housing component 6 to close the housing 2. In this process, the spring element 98 first slides past the sliding surface 108. It is bent by the sliding surface 108 in the foundation region, ie with respect to the bending axis extending in the longitudinal direction of the housing 2. This bend is also transmitted via web 100 which is elastically pretensioned. When the insertion operation continues, a certain amount of elastic pretension occurs in the corresponding element 92 which is pushed against the radiator element 14 by the deformation of the spring element 98. In response to this contact force a certain amount of elastic deformation occurs in the corresponding element 92.

Firstly, the upper housing component 6 is connected to the lower housing component 4 which is associated by a detent projection known per se.

Examples of the spring means 70, 90 shown in FIGS. 4 to 8 are preferably associated with each individual compartment 26 and consequently to a single heating rod 24, which are included in the heating rod 24. Pretension the components. In order to ensure the spring force generated by the spring means 70, 90, a detent connection is provided in the area of each spring means. The detent connection here connects the lower housing component 4 to the upper housing component 6 to prevent the upper housing component 6 from being lifted off of the lower housing component 4. This ensures the elastic tensioning of the spring means 70, 90. The detent connection is formed not only in the boundary region of the housing 2 but also in its intermediate portion directly adjacent to the compartment 26 when viewed in the transverse direction. To this end, an intermediate wall can be provided between the spacer 30 and the compartment 26, such that a detent projection formed in the upper housing component 6, for example, between the intermediate wall and the adjacent boundary wall of the compartment 26. And lock into engagement with a window opening formed on the intermediate wall. Structures of this type are shown in FIGS. 9 and 10, where the partition walls of compartment 26 are represented by reference numeral 110. The intermediate wall is indicated by reference numeral 112 and the detent opening in the intermediate wall 112 is indicated by reference numeral 114. The detent web, which engages with the detent opening 114 in the closed state of the housing, is indicated by reference numeral 116 in FIG.

2: housing 4: lower housing components
6: upper housing component 8: cover
10: opening 12: longitudinal web
14: radiator element 16: PTC heating element
18: PTC element 20: metal sheet strip
24: heating rod 26: compartment
30: spacer 31: web
32: housing cover portion 34: cross member
36: vent 38: housing cover segment
40: opening 42: transverse beam
44: spring means 46: support element
48: slope 50: fixed element
52: bottom 54: spring strip
56: spacer rib 58: contact element
59: contact surface 60: accommodation space
62: slot 64: bearing element
66: support rib 67: housing cover face
68: displacement element / corresponding element
70: spring means 74: displacement element
76: silicon string 78: slope
80: contact element 82: dorsal
84: sliding surface 86: contact protrusion
88: support 90: spring means
92: corresponding element 96: contact protrusion
98: spring element 100: web
102: longitudinal slot 104: longitudinal slot
106: support element 108: sliding surface
110: bulkhead 112: intermediate wall
114: detent opening 116: detent web

Claims (14)

An electric heating apparatus in which a plurality of PTC heating elements 16 and radiator elements 14 contacting on PTC heating elements 16 are supported in pretensioned contact with each other in an open housing,
The housing 2 forms a plurality of compartments 26, each of which has a separate heating rod 24 therein, each of the heating rods 24 being the PTC heating element. (16) and a radiator element (14) in contact with both sides of the PTC heating element (16), wherein the radiator element (14) and the PTC heating element (16) are in pretensioned contact with each other. Device.
The neighboring one of the plurality of compartments 26 is closed by a lower housing component 4 which is secured to the lower housing component 4 and exposes the spacer 30 therebetween, the spacer 30 is formed by the lower housing component and connects the neighboring compartments with each other.
3. Electric heating device according to claim 2, characterized in that the spacer (30) is embodied to be displaced inward with respect to the bottom (52) of the lower housing component (4) when viewed in the thickness direction of the electric heating device.
4. Electric heating device according to claim 2 or 3, characterized in that the spacer (30) has a ventilation opening (36).
5. The electrical device of claim 4, wherein each of the plurality of compartments 26 associates with the plurality of compartments 26 a spring element pretensioning the elements of the heating rods 14, 18, 20. Heating device.
6. The electric heating apparatus according to claim 5, wherein the spring element is made of plastic material.
7. The electric heating apparatus according to claim 6, wherein each of said heating rods (24) housed inside each of said plurality of compartments (26) defines a heating stage.
8. The heating apparatus of claim 7, wherein all of the PTC heating elements (16) and the radiator elements (14) of the electric heating device are combined to form respective heating rods (24), each of the plurality of heating rods (24) An electric heating device, characterized in that provided inside each of the compartments (26).
As a housing (2) for an electric heating device for accommodating a plurality of PTC heating elements (16) and radiator elements (14) in contact with the plurality of PTC heating elements (16) to be in pretensioned contact with each other,
A plurality of compartments in which the lower housing component 4 houses the PTC heating element 16 and at least one heating rod 24 comprising a radiator element 14 abutting the PTC heating element 16 on both sides ( And a plurality of compartments (26) spaced apart from each other by spacers (30).
10. A lower housing component (4) according to claim 9, wherein the lower housing component (4) covers a neighboring compartment of the plurality of compartments (26), and the housing cover portion (32) is adapted to be connected to the lower housing component (4) therebetween. A housing, characterized by exposing the spacer (30) defined by a lower housing component (4).
11. Housing according to claim 10, characterized in that each housing cover portion (32) is defined by a separate housing cover segment (38).
12. The housing according to claim 11, wherein the spacer (30) is embodied to be displaced inward with respect to the bottom (52) of the lower housing component (4) when viewed in the thickness direction of the housing (2).
13. Housing according to claim 11 or 12, characterized in that the spacer (30) comprises a web (31) connecting two of the compartments (26) to each other.
14. Housing according to claim 13, characterized in that the spacer (30) has a ventilation opening (36).

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