DE102015120183A1 - Radiator assembly for an electric heater and electric heater - Google Patents

Abstract

Disclosed are a modular radiator for an electric heater and a corresponding electrical heater, wherein either a radiator alone is used or a plurality of radiators are used adjacent to each other to deliver the heat of one or more heating elements.

Description

The invention relates to a radiator arrangement for a heater according to the preamble of patent claim 1.

In heaters, it is known to conductively connect an electrically operated PTC heating element with a radiator heat. Such a PTC heating element has a positive temperature coefficient and is characterized by a self-regulating effect, since it has an increased resistance with increasing heat and conducts less current, whereby the power consumption is reduced.

In order to transfer the heat or the heat from the heater to a medium to be heated, e.g. To improve air, the associated radiator is mostly designed with ribs extending away from the PTC heating element.

In the pamphlets DE 299 06 950 U1 respectively. EP 1047168 B1 the applicant discloses a heater for a control cabinet, in which a radiator is encompassed by a housing part. As a result, air flow channels are formed.

The Applicant various other heaters and radiators are known. A known radiator has e.g. Ribs which extend approximately radially away on one side of the radiator, while the ribs of the other side are aligned approximately parallel to each other.

The heat extraction of such radiators depends essentially on their surface area and surface finish, both parameters being determined by the production of the radiator. Accordingly, it is disadvantageous to the radiators of the prior art that their heat extraction is fixed, so that a variety of performance of heaters manufacturer always associated with different radiators.

In contrast, the invention is based on the object to provide a radiator and a heater whose heat output is variable, so that it is applicable to different power ranges.

This object is achieved by a radiator arrangement having the features of patent claim 1 and by a heater having the features of patent claim 11.

The claimed radiator assembly has at least one radiator, which may also be referred to as a heat spreader or convection body, configured to be placed in heat conductive communication with a PTC heating element. This is an electric heater can be formed. According to the invention, the radiator has a first group of contact surfaces, to which a further substantially identical radiator can be applied and, for example, via bonding or clamping or screws or welding or soldering or crimping in heat conductive connection can be brought. Essentially identical here may mean that in a respective relaxed state, the contact surfaces of the first group of a radiator are in one plane, while contact surfaces of the other radiator have a curvature. According to the invention thus results in a modular radiator assembly consisting of identical parts with at least two-stage selectable heat extraction. An appropriately equipped heater can have a heat output of about 170 watts at -20 ° C.

Preferably, the abutment surfaces of the first group are arranged in a first abutment plane or can be brought into this abutment plane by being pressed together with the further radiator. Then more than two contact surfaces can be brought simultaneously in heat conductive connection.

In a particularly preferred production-optimized development of the radiator is an extruded profile, preferably made of aluminum or an aluminum alloy. Thus, for example, at 175 mm length compared to the prior art, a weight reduction of 70 grams can be achieved. Preferably, the aluminum is anodized and / or painted. This results in a leveled temperature distribution with improved emission factor and further increased heat extraction.

Further advantageous embodiments of the invention are described in the dependent claims.

In a particularly preferred embodiment, the radiator has a second group of contact surfaces, to which also a further substantially identical radiator can be applied and, for example, via bonding or clamping or screws or welding or soldering or crimping in heat conductive connection can be brought. The result is a modular radiator arrangement consisting of one or two or three identical parts with three-stage selectable heat extraction.

If the abutment surfaces of the second group are arranged in a second abutment plane or can be brought into this second abutment plane by compression with the further radiator, more than two abutment surfaces of the second group can be brought into heat-conducting connection at the same time. It is particularly preferred if the two plant levels are symmetrical to each other.

If the abutment surfaces are spaced apart from each other so that free spaces remain between the abutment surfaces, during operation, heated medium can be exchanged between the abutment surfaces through the free spaces, if no further radiator abuts on the abutment surfaces. The contact surfaces of a group and the spaces between them together form a broad side of the radiator. The contact surfaces can occupy 60 to 80% of this wide side, while the free spaces occupy 20 to 40% of the same broad side.

In particular centrally between the contact surfaces of the second group, a free space can be developed as a groove, via which a further component can be attached to the radiator. The further component may be the further radiator.

A cross section of the radiator may have an approximately rectangular outer frame. As already mentioned, deviating or supplemental contact surfaces of one and the same group in their entirety can have a curvature towards the outside in a relaxed state of the radiator, so that viewed in cross section these contact surfaces have an arc shape to the outside. In other words, an abutment plane can have the curvature towards the outside, so that viewed in cross-section this abutment plane has an arc shape to the outside. For a crowning is created, via which an intimate connection of the inner (middle) contact surfaces with those of the other radiator can be produced.

The curvature or the arc shape is generated according to a first variant by a pressing process, by which preferably also the PTC heating element is clamped in the radiator. According to a second variant, the curvature or the arch shape is produced during extrusion of the radiator.

According to a particularly preferred embodiment, the contact surfaces are arranged on respective planar strip-shaped contact elements. This results in an elongate radiator, which can be produced advantageously in the extrusion process.

For the formation of fireplaces and for optimized heat transfer, the contact elements can be fastened via a respective web to a main section into which the PTC heating element can be used with heat conductively-preferably clamped. The webs are preferably arranged perpendicular to the respective contact element. This results in a T- or L-shape of the contact element with the respective web.

The PTC heating element is preferably clamped in and surrounded by the interior of the main section. in the case of the extruded profile, one of the two openings of the main section is provided for a power supply, while the other opening is completely closed with a seal.

Preferably, in a first narrow outer side of the radiator, a first groove is provided, via which a contact protection or a fastening clip (according to DIN) for the radiator or the heater formed therewith can be fastened. The attachment can be done by screws, which are screwed into the groove.

If the groove has an extended groove base over which a screw channel is formed, a screw can also be screwed in along the groove there - in the extrusion profile along its pressing direction.

An advantageous development of the radiator is symmetrical to a median plane. In this case, in a second narrow outer side of the radiator, which is mirror-symmetrical to the first narrow outer side, a second groove may be provided. About this is also one of the two components mentioned above, so a mounting clip or a contact protection on the radiator fastened. If the two grooves each have an extended groove bottom, over each of which a screw is formed, a terminal block or a connection housing for the PTC heating element can be securely attached to one end of the radiator via two screws.

The heater according to the invention has at least two above-described radiators, which are in thermal conduction with their respective group of contact surfaces in heat. Only one of the radiators is in direct heat conductive connection with a PTC heating element. The other radiator is in indirect heat conducting connection with the PTC heating element. Without a fan it is possible to reach approx. 180-350 Watt and with fan> 500 Watt each at -20 ° C. Preferably, the PTC heating element is clamped in the main portion of the affected radiator.

When the heater according to the invention has three radiators, a middle radiator with the abutment surfaces of each of its two groups is in heat conducting communication with a respective outer radiator. According to a first variant, only the middle radiator is in direct heat conducting connection with a PTC heating element. Again, the PTC heating element is preferably clamped in the main portion of the affected central radiator. According to a second variant, only the two outer radiators are in direct heat conductive connection with a respective PTC heating element. Again, the two PTC heating elements are preferably clamped in the respective main section of the two outer radiators concerned. Without a fan it is possible to reach about 400 watts and with fan about 530 watts each at -20 ° C.

A particular advantage of the radiator arrangement according to the invention is that even more than three radiators can be composed of heat conductively. The number of PTC heating elements is variable.

Particularly preferred is a heater with radiators whose outer contact elements are gripped or gripped behind by means of clamps and are thus tensioned against one another.

The heater can also be used as a tube heater, wherein approximately circular segment-shaped adapter are used in areas between the radiators and an inner wall of the tube. Preferably, the tube heater in the direction of its extrusion and thus can be flowed through along its contact elements and its webs.

If the heater has a fan, the output heat output can be increased significantly, as the convection flow is increased.

The heater can also be used for a control cabinet.

Several embodiments of a heater according to the invention with one or more radiators are shown in the figures. Show it:

1 in a longitudinal section a heater according to the invention according to a first embodiment;

2 in a cross section the heater off 1 ;

3 in a perspective view of a heater according to a second embodiment;

4 in a perspective view of a further development of the heater 3 ;

5 in a cross section a heater according to a third embodiment as an exploded view;

6 in a cross section a heater according to a fourth embodiment; and

7 in a perspective view of a further development of the heater 6 ,

1 shows a longitudinal section of a heater according to the invention according to a first embodiment. He has a radiator 1 , which is designed as aluminum extruded profile. In a middle area of the radiator 1 is a tubular flat main section 2 provided, the front side each with a made of silicone gasket 4 is closed. Through one of the two seals 4 are insulated connecting wires 6 led to the electrical supply one in the main section 2 clamped PTC heating element 8th are provided. Furthermore, an insulating sleeve 10 Kapton for the PTC heating element 8th intended.

2 shows the heater off 1 in a cross section. The radiator 1 has in this cross-section has an approximately rectangular outer frame, resulting in a first broad side 12 and a second broad side 14 and two narrow sides 16 of the radiator 1 result. The two broad sides 12 . 14 have in the in 2 shown relaxed state of the radiator 1 in each case a slight curvature to the outside. These bulges are in the first embodiment of the heater according to the invention with only one radiator 1 irrelevant and serve in a radiator system with two or three radiators 1 for generating an intimate heat conductive connection, which is related to the 5 and 6 is explained.

The radiator 1 of the first embodiment spans in its main section 2 the PTC heating element 8th a, allowing a heat conductive connection between the PTC heating element 8th and the radiator 1 given is. At the main section 2 are in the range of the first broad side 12 five investment elements 18 a first group disposed on the respective outer side of a respective contact surface 20 the first group is formed. In a basically comparable way are in the range of the second broad side 14 four plant elements 22 a second group disposed on the respective outer side of a corresponding contact surface 24 the second group is formed. In the middle of the second broad side 14 is a fifth interrupted by a groove investment element 22a arranged the second group, on which an interrupted by the groove contact surface 24a the second group is formed.

All investment elements 18 . 22 . 22a are elongated and strip-like and extend perpendicular to the plane of the 2 , Furthermore, all investment elements 18 . 22 over a respective bridge 26 with the main section 2 connected. So that's inside the radiator 1 between the bridges 26 and the investment elements 18 . 22 Chimneys formed whose cross-section are enlarged compared to the star-shaped ribs of the prior art, so that the flow through a medium to be heated is improved and heat accumulation is avoided.

The radiator 1 is mirror-symmetrical to a median plane 32 designed. On the two narrow sides 16 of the radiator 1 is each a groove 28 provided, the respective groove base as a screw 30 is trained. 1 shows a fastening clip 34 that's on the first narrow side 16 is attached. More specifically, the mounting clip 34 over one into the groove 28 screwed in screw 36 attached.

3 shows a perspective view of a second embodiment of a heater according to the invention. The radiator corresponds to this 1 with the fastening clip 34 and the screw 36 that of the first embodiment according to the 1 and 2 , Only the power supply of the heater is changed. More specifically, on one of the end faces of the radiator 1 a terminal block 38 attached. Serve with two screws 40 in the two screw channels 30 are screwed, extending along the radiator 1 extend, and the (according to 2 ) at the groove bottom of the grooves 28 are formed. About the terminal block 38 is the electrical contact by means (not shown) lead easily feasible.

4 shows in a perspective view of a development of the second embodiment of the heater according to the invention with a radiator 1 according to 3 , The radiator 1 is three-sided, on the two broad sides 12 . 14 and at the attachment clip 34 opposite narrow side 16 with a touch guard 42 covered. In the area of the two broad sides 12 . 14 the contact protection has a variety of transversely to the radiator 1 running ventilation slots 44 , Furthermore, the contact protection 42 a support section 46 that has two screws 48 on the narrow side 16 of the radiator 1 is attached. These are the two screws 48 in the local groove 28 screwed.

5 shows in an exploded view or in a not yet mounted state, a heater according to a third embodiment. It contains the heater of the first embodiment according to 2 with the radiator 1 and additionally another identical radiator 50 , in which no PTC heating element is used. The two radiators 1 . 50 be with their respective first broad pages 12 brought into contact with each other. More precisely, the five contact surfaces 20 the first group of the first radiator 1 with the five contact surfaces 20 the first group of the further radiator 50 Heat conductive tensioned against each other. For bracing and securing are on each side brackets 52 over the outer investment elements 18 pushed.

As related to 2 was explained, has the radiator 1 that with the PTC heating element 8th is provided, a crown, so a curvature of the contact surfaces 20 the first group. This crowning is either when pressing the radiator 1 with the PTC heating element 8th or when extruding the designed as aluminum profile radiator 1 been generated.

In the illustrated embodiment according to 5 has the further radiator 50 no crowning, so that the attachment elements 18 the first group are arranged in a plane and thereby parallel to the investment elements 22 the second group of the further radiator 50 are aligned. Through the interaction of the arched first group of the radiator 1 with the flat first group of the further radiator 50 arises during compression of the outer contact elements 18 over the brackets 52 in any case, z. B. even with larger manufacturing tolerances, an intimate connection and the three inner contact surfaces of the first groups.

6 shows in a cross section an already mounted fourth embodiment of the heater according to the invention. It has a radiator system consisting of three essentially identical radiators 1 . 50 , wherein the heat conducting connection of the middle radiator 1 with the (in 6 lower) further radiator 50 of those 5 equivalent. The in 6 upper further radiator 50 is complementary to the middle radiator 1 , more precisely to the contact surfaces 24 . 24a curious about his second group. A special feature here is that the interrupted by the groove contact surface 24a the second group of the middle radiator 1 in contact with the middle contact surface 20 the first group of the upper further radiator 50 arrives. Again, this is about the brackets 52 an intimate and heat-conducting plant, because (according to 5 ) also the contact surfaces 24 . 24a the second group of the radiator 1 are arched.

7 shows in a perspective view of the fourth embodiment according to 6 of the heater according to the invention with that of three radiators 1 . 50 composite radiator system. It can be seen that for each connection of two radiators 1 . 50 two brackets on each side 52 are provided. At the middle radiator 1 is the terminal block 38 and the fastening clip 34 screwed on (cf. 3 ). This is the heater according to 3 by attaching two more radiators 50 modular extended so that its surface is increased many times, and that the (in 7 not shown) single average PTC heating element can absorb a comparatively large power and convert it into heat. This applies in particular if, in addition, a fan (not shown) is provided, which supplies an air flow along the strip-shaped contact elements 18 . 22 . 22a and the corresponding bars 26 promotes.

Disclosed are a modular radiator for an electric heater and a corresponding electrical heater, wherein either a radiator alone is used or a plurality of radiators are used adjacent to each other to deliver the heat of one or more heating elements.

LIST OF REFERENCE NUMBERS

1

radiator

2

main section

4

poetry

6

braid

8th

PTC heating element

10

insulation

12

first broad side

14

second broad side

16

narrow side

18

Investment element (the first group)

20

Investment area (the first group)

22

Investment element (the second group)

24

Investment area (the second group)

22a

groove interrupted by groove (the second group)

24a

interrupted by groove contact surface (the second group)

26

web

28

groove

30

screw

32

midplane

34

mounting clip

36

screw

38

terminal block

40

screw

42

contact protection

44

vent

46

supporting section

48

screw

50

another radiator

52

clip

QUOTES INCLUDE IN THE DESCRIPTION

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

Cited patent literature

• DE 29906950 U1 [0004]
• EP 1047168 B1 [0004]

Claims (16)

Radiator arrangement with at least one radiator ( 1 ) which is in heat-conducting connection with a PTC heating element for forming an electrical heater ( 8th ), characterized in that the radiator ( 1 ) a first group of contact surfaces ( 20 ), to which another essentially identical radiator ( 50 ) attachable and in heat conductive connection can be brought. Radiator assembly according to claim 1, wherein the radiator ( 1 ) is an extruded profile. Radiator arrangement according to claim 1 or 2, wherein the radiator ( 1 ) a second group of contact surfaces ( 24 . 24a ), to which another substantially identical radiator ( 50 ) attachable and in heat conductive connection can be brought. Radiator arrangement according to one of the preceding claims, wherein the radiator ( 1 ) has an approximately rectangular outer frame in cross-section. Radiator arrangement according to one of the preceding claims, wherein in a relaxed state of the radiator ( 1 ) the contact surfaces ( 20 . 24 . 24a ) a group in its entirety have a curvature to the outside. Radiator arrangement according to one of the preceding claims, wherein the contact surfaces ( 20 . 24 . 24a ) on respective planar strip-shaped contact elements ( 18 . 22 . 22a ) are arranged. Radiator assembly according to claim 6, wherein the abutment elements ( 18 . 22 ) over a respective bridge ( 26 ) on a main section ( 2 ) into which the PTC heating element ( 8th ) Heat conductive is used. Radiator arrangement according to one of the preceding claims, having a first narrow side ( 16 ), in which a first groove ( 28 ), via which a contact protection ( 42 ) or a fastening clip ( 34 ) for the radiator ( 1 ) or the heater formed therewith is attachable to this. Radiator assembly according to claim 8, wherein the groove ( 28 ) has a groove base through which a screw ( 30 ) is formed, in which a screw ( 40 ) along the groove ( 28 ) can be screwed. Radiator arrangement according to one of the preceding claims, wherein the radiator ( 1 ) symmetrical to a median plane ( 32 ). Heater with a radiator arrangement according to one of the preceding claims, whose radiators ( 1 . 50 ) over respective contact surfaces ( 20 ) are in heat conductive connection, wherein in at least one of the radiators ( 1 ) a PTC heating element ( 8th ) is inserted so that this radiator ( 1 ) in direct heat-conducting connection with the PTC heating element ( 8th ). A heater according to claim 11, wherein a middle radiator ( 1 ) over both groups of contact surfaces ( 20 . 24 . 24a ) with a respective outer radiator ( 50 ) is in heat conducting connection, and wherein in the middle radiator ( 1 ) a PTC heating element ( 8th ) is inserted so that the middle radiator ( 1 ) in direct heat-conducting connection with a PTC heating element ( 8th ), or wherein in each of the two outer radiators a PTC heating element ( 8th ) is inserted so that these two radiators in direct heat conductive connection with the respective PTC heating element ( 8th ) are.  A heater according to claim 11 or 12, wherein more than three radiators are in heat conducting communication via their contact surfaces. A heater according to any one of claims 11 to 13, comprising a radiator assembly according to claim 6, wherein the outer abutment elements ( 18 . 22 ) by means of parentheses ( 52 ) are embraced and stretched against each other. Heater according to one of claims 11 to 14, which is designed as a tube heater, wherein at the radiators ( 1 . 50 ) are provided approximately circular segment-shaped adapter.  Heater according to one of claims 11 to 15 with a fan.

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