DE29622101U1 - radiator - Google Patents

Description

SCHWABE · SANDMAIR · MAPX. .: .", .".
PATENT ATTORNEYS &iacgr;*"&idigr;'*;**'*"·

STUNTZSTRASSE16 · D-81677 MUNICH

Attorney file: 41 782 VII

Kermi GmbH

Pankofen Station 1

94447 Plattling

radiator

The invention relates to a radiator, in particular for heating systems, for example for central and district heating systems or a cooling body, with a supply for a heating medium, with a discharge for a heating medium, with a line between the supply and the discharge and with a surface for radiating the heat of the heating medium, according to the preamble of claim 1 or claim 14.

Various types of radiators are known in the state of the art. For example, radiators with one or more heating plates are currently commonly used radiators. To produce plate radiators, two sheets are usually made, each with an embossed half cross-section of a line for receiving and transporting a heating medium, which are welded together to complete the heating plate, whereby the line for the heating medium, preferably water, is completed. In order to hide the line register provided by embossing in the heating plate, the front heating plate of the known heating device is later

Bayer. Vereinsbank Munich 453100 (bank code 700 202 70)

(089)4707064 (089)47 07120 524560 DE 1307 46066 Hypo-Bank Munich 4410122850 (bank code 700 20001)

Fax: Telex: VAT: (089) 47 07120 524560 DE 1307 46066 (0 89) 4706417 Swan d 0 89) 41900025

They are often provided with a covering, for example by clamping or gluing them on.

Such heating devices, as presented in DE 38 38 513.9 Al, for example, also have the disadvantage that the manufacture of such a heating device is complex, since a large amount of energy is required to press the sheets and then weld them together over a large area to ensure they are watertight. The requirement to weld large areas also results in a relatively high number of leaks, and consequently defective radiators must be reworked. Radiators that cannot be reworked also occur. The inspection of the weld seams in a water basin is also regularly required and represents an additional work step that increases the manufacturing costs of the known heating device considerably. In addition, known radiators of this type need to be improved in terms of their pressure resistance.

In addition, it is also necessary for the panel radiators of the state of the art described above to use steel sheets that are thicker than is absolutely necessary, because the embossing or pressing of the sheet metal plates sometimes results in their wall thickness being thinner. However, in order to be able to maintain a minimum wall thickness, it is necessary to work with sheet thicknesses that would otherwise in principle be oversized.

It is also worth mentioning that known panel radiators work mainly by emitting convection heat, i.e. air rising up the panel radiator is heated and distributed through the movement mentioned in a room in a building to be heated. This dry, warm air is usually detrimental to the health of the room occupants, especially since convection heat stirs up dust. Consequently, a radiator that at least mainly works with radiant heat is preferable, since the radiant heat provides the occupants of a building with a pleasant warmth when the room temperature is low.

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without having to fear excessive air movement and thus dust development.

Other radiators, such as sectional radiators, can only be manufactured with an even greater amount of work and energy and work with an even higher proportion of convection heat emission.

In addition, radiators have become known that are arranged in the form of skirting board heating in the floor area of a building. This type of radiator also works largely with convection heat. Due to the small surface area of such a radiator, it works essentially with convection heat and only to a small extent with direct or indirect radiant heat. The direct radiant heat is emitted by the small areas of the skirting board heating directed into the room. A larger part of the radiant heat is generated by the rising hot air heating the wall areas above the skirting board heating, whereby the walls become heat radiators and the radiant surface of the skirting board heating is indirectly increased. The effectiveness of such known radiators is questionable and the air flow rising from the floor that brushes the walls of a building ensures that the walls become unsightly discolored after a short time due to the deposition of dirt particles such as dust and the like.

It is the object of the present invention to propose a heating device and a method for producing, in particular, a heating device according to the invention, which remedy the disadvantages of the prior art as far as possible. Preferably, a heating device or a method should be proposed which can be produced or used easily and without problems.

This object is achieved by a radiator with the features listed in patent claim 1 and a method with the features listed in patent claim 14.

steps. Appropriate embodiments or process variants are defined in the subclaims.

The advantages to be achieved according to the present invention are based on the fact that a heating or cooling body, in particular for central and district heating systems or ceiling cooling systems, is proposed, in which according to the invention the heat radiation surface has a profile which surrounds the line, in particular a pipe, in cross-section at least in some areas, preferably over an angle range of approx. 90° to approx. 200°, preferably in approximately 120°, the line being dimensioned in its cross-sectional dimensions in relation to the profile, or vice versa, that a gap of less than 0.1 mm, preferably less than 0.05 mm, is present between the surface and the line in the assembled state.

This design ensures that the line, especially in the form of a pipe, has a very good heat exchange with the heat radiation surface, so that the heat supplied by the heating medium can be emitted as radiant heat via the heat radiation surface. The large-area contact of the line with the heat radiation surface results in effective heat transfer, and by providing only a very narrow gap, the heat transfer is kept reproducibly in an advantageous range. The use of a separate line or a separate pipe ensures that no leak tests are required in order to be able to release the ultimately manufactured heating or cooling body for sale, since lines and in particular pipes can usually be manufactured to be leak-tight.

In order to be able to provide the required heat output, a pipe length of around 18 m is laid on a heat radiation surface of around 1 m². The pressure loss that the heating medium experiences when it is passed through a pipe length of this size and with a pipe or pipe cross-section of 12 x 0.7 or 14 x 1 is so great that larger pipe diameters are also preferred for the production of larger heat radiation surfaces.

Welded pipes that are not drawn can be used, as they are much more cost-effective than drawn pipes.

A heating or cooling element according to the invention can be manufactured with only about 15 components, while about 30 parts are required to assemble conventional panel radiators. This also makes it clear how much more cost-effective a heating or cooling element according to the present invention is to manufacture and how much less susceptible such a heating or cooling element (hereinafter referred to as a radiator) is, since fewer assembly errors can occur when a smaller number of parts are arranged.

Preferably, the profiling surrounds the line, in particular the pipeline, under tension. This can create a far improved heat transfer between the line and the heat radiation surface. The outer diameter can be up to 0.5 mm, preferably up to approximately 0.3 mm larger than the inner diameter of the profiling.

The profiling in the heat radiation surface can be connected to the line by welding, soldering, gluing or similar. It is important to ensure that the resulting heat transfer justifies the connection effort, i.e. that the heat transfer is improved compared to the previous embodiments.

A particularly advantageous embodiment of the radiator according to the invention is obtained if the line is connected to the heat radiation surface or the profile by projection welding using electric current. When projection welding, visible deformations of the sheet metal of the heat radiation surface can occur from the visible side of the heat radiation surface, but these can be avoided by the method according to the invention to be described below. In this case, a defined projection, i.e. a projection, is not created by

Punching is not produced from one side of the heat radiation sheet or the line, but the defined weld projections are formed by mechanical, partial machining, partial punching peripherally to the surface of the non-visible side of the heat radiation surface or by other mechanical influences to form defined elevations.

The resulting small contact surfaces between the pipe to be connected and the heat radiation surface make it possible to allow only small currents to flow in order to connect the pipe to the heat radiation surface preferably in the profile. This also makes it possible to use welded pipes that would otherwise be difficult to use.

Preferably, the diameter of the pipe is slightly larger than the inner diameter provided by the profiling, which is embossed or punched into the sheet metal of the heat radiation surface. Because the pipe is advantageously mechanically less stable than the heat radiation surface or its profiling, the pipe, in particular the pipe, can fit particularly well into the profiling by deformation, so that the heat transfer can be significantly improved.

In order to be able to increase the heat dissipation performance of the heating element according to the invention in an advantageous manner, it can be provided with a convection body, which can be placed on the heat radiation surface on the line side. This allows a heat flow to flow into the convection body and increase the performance of the heating element according to the invention by enlarging the heat dissipation surface.

The convection body can be provided with a profile on the line side. This profile can surround the line inserted or pressed into the heat radiation surface in cross-section at least in some areas, preferably over an angle range of approximately 120°, whereby the line, preferably a pipe,

its cross-section has dimensions such that the profiling is dimensioned so that a gap of less than 0.1 mm, preferably less than 0.05 mm, results between the convection body and the line or the convection body and the heat radiation surface when installed. The profiling of the heat radiation body can enclose the line under tension.

The connection techniques already mentioned above can also be used here, whereby appropriate dimensions and material properties of the line, for example pipe, and the convection body can be used. By adding the convection body in a preferred embodiment, the output of a heating body according to the invention can be increased from approx. 1,200 watts per square meter to approx. 2,000 watts per square meter.

In order to be able to further increase the performance of the heating element according to the invention, an additional line can be provided on the rear surface of the convection body, which is connected in particular in parallel to the line in terms of flow technology.

In this case, a profile can be provided on the back of the convection body, as already explained above, in order to enable improved heat transfer between the convection body and the additional line.

Of course, it is also possible to arrange an additional convection body on the back surface of the convection body with an extra additional line, etc.

The convection body or bodies have convection chimneys, which preferably have a cross-section of at least 2 cm. If several convection bodies are to be arranged, it can be advantageous if the convection bodies interlock with one another with their extensions, whereby a gap of at least 2 cm should remain between the convection body extensions in order to allow the warming air to rise unhindered. The extensions can

the convection body can be of different dimensions or can interlock in the form of saw teeth or the like. It goes without saying that this type of arrangement of convection bodies can be used not only with the heating element according to the invention, but also with any type of heating element or cooling element in which convection elements can be used. This embodiment makes it possible to provide a heating element or cooling element with a particularly small installation depth.

In the case of radiators with two at least essentially parallel, longer heating pipe sections, it has been shown that during operation it regularly happens that a flow is only caused by one of the two heating pipe sections. When the distributor pump starts up in a central heating system, it has to overcome the line resistance of sometimes considerable lengths of heating pipes in radiators with curved and long heating pipe sections with a comparatively modest output. Due to slight manufacturing tolerances, possibly gas bubbles or the like in one of the pipes, it now almost regularly happens that the line resistances of the two heating pipe sections of a corresponding radiator are not completely identical. In this way, a flow initially occurs through one of the two heating line sections of a corresponding radiator or cooling body, and the line resistance of the heating line section through which the flow does not pass is consequently so great compared to that through which the flow has already been set in motion that the heating medium cannot be put into a flow state through the second, non-flowing heating line section.

In order to remedy this disadvantage, the invention proposes a heating or cooling element with at least two heating line sections that run essentially parallel to one another, with the two heating line sections being brought together at their two ends. The heating lines open into a common return line at their return ends, and the forward ends

The heating pipes are arranged at the beginning of the heating pipes in the flow direction of the heating medium.

The advantage of this heating or cooling element according to a further aspect of the invention is that, in contrast to known heating elements, the heating lines are supplied with air from below and not from above, contrary to the known scheme, and are brought together at the upper end. In this way, the heating medium must rise from bottom to top and cannot, as in the prior art, fall from the top from the flow line to the return line in the heating element or on the heating element. Furthermore, with a heating or cooling element with the aforementioned inventive design, it is not possible for gas bubbles to remain in the heating element or in the heating line sections of the heating element.

The heating or cooling body according to the invention allows a flow to flow regularly through both heating line sections without any additional measures being required. In addition, the type of heating or cooling body according to the invention can be vented or drained much more easily, for example for assembly or maintenance work.

It is particularly advantageous if the return lines are arranged at the upper section of the heating or cooling body or at the rear end of the heating lines in the direction of flow of the heating medium. This design also helps prevent a heating medium from flowing through just one of the heating line sections, while the other heating line section is not included in the heating circuit.

Although various types of line branches or line junctions can be used, T-pieces have proven to be particularly useful for merging the heating line sections at the upper end or at the return end of the heating line sections, while Y-pieces are used in the area of the flow of the two heating line sections or the correspondingly designed radiator.

are particularly useful. It is possible to use a T-piece only on the return end, while any distributor connection can be provided on the supply end.

It is essential that, solely due to the design of the connections and the fact that the heating or cooling body designed according to the invention is subjected to the opposite flow of the heating or cooling medium to what is usual in the prior art, it is ensured that all existing and at least essentially parallel heating or cooling line sections are evenly flowed through with the heating medium or cooling medium.

According to a particularly preferred embodiment of the invention, the return line has a different cross-section than the heating line or heating lines. While the heating line or, in the case of several heating lines, the two or three heating lines have a line cross-section that is in a range in which a noticeable capillary effect of the heating lines still occurs, the return line should not have anything to counteract this capillary effect or this capillary pressure, since otherwise both the venting of the existing heating lines and the ventilation, i.e. allowing the heating lines to drain, can become problematic. Provided, therefore, that the static pressure and the flow pressure of the return line and the heating lines are the same, which is not unrealistic, at least the capillary pressure properties of the return line and the heating lines should be different, so that the total pressure of the return line or the heating lines is different, so that when filling a corresponding heating or cooling body designed according to the invention, no problems arise in that one of the existing heating lines installed in parallel cannot be vented or ventilated, i.e. emptied.

If the design of the entire heating or cooling body according to the invention is considered, it must be noted, especially when more than two heating lines are provided opposite a return line, that for the purposes of

During ventilation or venting, the pressure sum, i.e. the total pressure consisting of the static pressure, the flow pressure and the capillary pressure, on the return side should be different from the total pressure or the pressure sum on the flow side, including the heating pipes, in order to preferably also provide an imbalance for emptying a corresponding heating or cooling element, so that the heating medium cannot remain in the heating element and must drain away, and conversely, no air bubbles can remain in the heating pipes.

The present invention is explained in more detail below with reference to the attached figures using preferred embodiments. Further features and advantages as well as tasks according to the invention are disclosed. The figures show:

Fig. 1 shows a preferred embodiment of a heat radiation surface of a heating or cooling body according to the invention in a rear plan view;

Fig. 2 shows the heat radiation surface according to Fig. 1 with the pipe inserted;

Fig. 3 shows a preferred embodiment of a heating or cooling body, in particular according to Figs. 1 and 2, with an embodiment of a convection body in a rear plan view;

Fig. 4 shows a heating or cooling element according to Fig. 3 with an additional line in a rear view; and

Fig. 5 shows a further preferred embodiment of a heating or cooling body designed according to the invention in a rear view.

The reference symbols used in the following illustrations designate identical or at least functionally identical components, whereby reference symbols increased by decades also have corresponding designation functions (e.g. 12 corresponds to 112).

The embodiment of a heat radiation surface 12 of a radiator 10 with a side panel 12a attached to it, shown in Fig. 1, has profiles 14 that can be embossed into the sheet metal of the heat radiation surface 12. The profile 14 has raised, preferably slanted areas 14a, 14b that protrude from the sheet metal, between which an approximately round area 14c runs, into which a round tube can later be pressed.

The reference number 30 designates projection welding areas that can be embossed in a conventional manner, preferably in such a way that the embossing points remain as hidden as possible from the view of an observer, i.e. in the profiling area that is oriented downwards in the later installation position of the radiator according to the invention.

The raised areas 30 are preferably provided by, for example, striking the material of the heat radiation surface 12 at an acute angle with a sharp tool or scraping it over it until a defined projection is produced, whereby this profiling, which is used for a projection welding process, is hardly or not at all visible from the front of the heat radiation surface 12 or the radiator 10. It is sufficient to provide the projections for projection welding at certain intervals in a line or offset or in several lines.

The welding projections or the defined projections can also be provided on the pipeline (not shown). On the other hand, it is also possible to provide the pipeline or the profile 14 in the heat radiation surface 12 in some areas with a knurled-like profile or with at least a section-wise thread or the like in order to implement a projection welding process.

The diameter of the profiled edge 14 will generally be somewhat smaller than the diameter of the line to be pressed in. In this case, especially if the line is less stable than the profiled edge, a particularly small gap will form between the pipe and the profiled edge 14 to 14c, so that a particularly effective heat transfer between the line or pipe and the heat radiation surface 12 is made possible.

Experience has shown that the diameter of the pipe can be about 0.3 mm larger than the pitch circle diameter of the profile. With larger diameter differences, the pipe or line can become deformed, hindering flow, or the profile in connection with the surface of the sheet of the heat radiation surface can become warped or distorted. The resulting gap between the pipe or heating coil (not shown here) and the material of the profile or heat radiation surface 12 should not be more than 1/10 mm, preferably less than 5/100 mm. By pressing the pipe or line (not shown here) into the profile 12, a positive connection is achieved, which enables advantageous heat transfer, whereby sufficient mechanical stability can be achieved by the specified projection spot welding.

In addition to the elements shown in Fig. 1, Fig. 2 shows a pipe 16 which has already been pressed into the profile 14 and may also have been welded, soldered, glued or otherwise secured, preferably secured by projection welding using a large electric current. The design of the bends in the pipe coil 16 is limited to a minimum of about 40 mm, preferably 50 mm, with regard to the pipe inner diameter of a bend 16a, if no deformations of the pipe or pipe 16 which impede the conduction of the heat medium can be tolerated. This applies in particular to pipe diameters of the pipe coil of 12 x 0.7 or 14 x 1.

Fig. 3 shows a preferred embodiment of a heating or cooling body 100 according to the invention, which can in principle be designed in the same way as that according to Fig. 2, but with a convection body 118 attached to the back of the heat radiation surface 112. The convection body 118 has convection shafts 122, which can be designed regularly or irregularly in the convection body 118. The convection body 118 has corresponding profiles 120, as are already provided in the heat radiation surface for receiving the pipe 116. The profiles 114, 120 in the heat radiation surface 112 or in the convection body 118 are preferably designed in such a way that they together at least approximately completely enclose the pipe. The convection body 118 itself does not have to have surface contact with the heat radiation surface 112.

Additional profiled rings 124 can be provided on the rear surface of the convection body 118, which, as can be seen from Fig. 4, can accommodate an additional heating coil 126. The connection technology between the convection body 118 and the line 116 as well as the line 126 can be similar or identical.

In Figure 5, a heating or cooling body with features according to the invention is generally designated by the reference numeral 200.

Two heating line sections 216, 226 are also provided for this type of radiator 200. While the front heating line section 216, attached to the plan front 212, is also partially surrounded by a convection body on its rear side, the rear heating line section 226 is only held in suitable recesses in the convection body 222. At the upper end of the heating line sections 216, 226, which is assigned to a return 256, a T-piece 250 is provided, which brings the two heating line sections 216, 226 together and opens into a return pipe 254, which is connected via a flexible connecting line 264b to a connection valve block 260 with the return 256 and a flow 258. The radiator 200 is mounted on the upper section of the connection fitting 260 on

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a mounting plate 262, to which the two flexible line sections 264b, 264a are connected, which provide a flow and a return directly for the radiator.

Viewed from the flow line 258 of the connection fitting 260, there is a distributor fitting 252 connected to the fitting 260 in the flow direction of the heating medium or the cooling medium, via which the medium is distributed from the flow line 258 to both heating line sections or cooling line sections 216, 226. In the present case, the distributor 252 is a Y-piece. However, it would also be conceivable to use a T-piece at this point, although a Y-piece is preferable due to its flow properties.

The embodiment shown in Figure 5 with features according to the invention makes it possible to prevent one of the heating line sections 216, 226 from being excluded from the circuit of the heating or cooling medium.

Of course, a heating element 200 can also be designed with three or more heating line sections, which then have to be connected with connectors that are equivalent to those with the reference numerals 250 and 252. This can be done, for example, by connecting the remaining or remaining additional heating line sections via connecting line extensions, the line resistance of which corresponds at least essentially to that of the connections for the other heating or cooling line sections.

Claims (20)

Protection claims 1. Heating or cooling elements, in particular for central or district heating systems or ceiling cooling or the like, with a supply for a heating medium, with a discharge for a heating medium, with a line between the supply and the discharge, with a surface for radiating the heat of the heating medium, characterized by the following features: a) the surface has a profile which surrounds the line in cross-section at least in regions, preferably over an angle range of 90° to 200°, in particular of approximately 120°, whereby b) the line, preferably a pipe, is dimensioned in its cross-sectional dimensions in relation to the profiling, or vice versa, such that a gap of less than 0.1 mm, preferably a maximum of 0.05 mm, remains between the heat radiation surface (12, 112) and the line (16, 116) in the assembled state. 2. Heating or cooling body according to claim 1, characterized in that the profiling (14, 114) surrounds the line (16, 116) under tension, the line in particular having a larger outer diameter than the inner diameter of the profiling (14, 114), the diameter difference preferably being less than or equal to 0.5 mm, in particular 0.3 mm. 3. Heating or cooling body according to one of claims 1 or 2, characterized in that the profiling (14, 114), ie the heat radiation surface (12, 112), can be connected to the line (16, 116) by welding, soldering, gluing or the like. 4. Heating or cooling body according to one of claims 1 or 2, characterized in that the line, in particular pipe (16, 116) is welded by projection welding. Bayer. Vereinsbank Munich 453100 (bank code 700202 70) Hypo-Bank Munich 4410122850 (bank code 70020001) Postbank Munich 653 43-808 (bank code 700 too 80} ■S" Fax: Telex: VAT: (089) 4707064 (0 89)4707120 524560 DE 130746066 (069) 4705009 (089)4706417 Swan d (089) 41900025 ßen with the heat radiation surface (12, 112) or the profiling (14, 114) can be connected. 5. Heating or cooling body according to one of claims 1 to 4, characterized in that the line (16, 116) is mechanically less stable than the heat radiation surface (12, 112) or its profiling (14, 114). 6. Heating or cooling body according to one of claims 4 or 5, characterized in that the line (16, 116) and/or the heat radiation surface (12, 112) is preferably provided with one-sided projection weld elevations at least in areas of the profiling in order to produce a connection between the line and the heat radiation surface or its profiling. 7. Heating or cooling body according to one of claims 1 to 6, characterized in that a convection body (118) is provided with the following features: a) the convection body (118) has a profile (120) which surrounds the line (116) in cross-section at least in regions, preferably over an angle range of approximately 100° to approximately 220°, preferably approximately 120°, wherein b) the line, preferably a pipe, is dimensioned in its cross-sectional dimensions in relation to the profiling (120), or vice versa, such that a gap of less than 0.1 mm, preferably less than or equal to 0.5 mm, remains between the profiling of the convection body (118) and the line (116). 8. Heating or cooling body according to claim 7, characterized in that it comprises the features of at least one of claims 2 to 6. 9. Heating or cooling body according to one of claims 7 or 8, characterized in that an additional line (126) is arranged on the rear surface of the convection body (118), which is preferably connected in a fluidically parallel manner to the line (116). 10. Heating or cooling body according to claim 9, characterized in that the rear surface of the cooling body (118) comprises the following features: a) the rear surface has a profile (124) which surrounds the additional line (126) in cross-section at least in regions, preferably over an angle range of 100° to 220°, in particular approximately 120°, whereby b) the additional line (126), preferably a pipe, is dimensioned in its cross-sectional dimensions in relation to the profiling (124), or vice versa, such that a gap of less than 0.1 mm, preferably a maximum of 0.05 mm, is present between the surface and the line in the assembled state. 11. Heating or cooling body according to claim 10, characterized by the features of at least one of claims 2 to 6. 12. Heating or cooling body according to one of claims 7 to 11, characterized in that an additional convection body is attached to the rear surface of the convection body. 13. Heating or cooling body according to one of claims 7 to 12, characterized in that in the case of several convection bodies, these interlock with their convection shafts, whereby convection shafts with dimensions of at least 2 cm are preferred. 14. Heating or cooling body according to the preamble of claim 1, or one of claims 7 to 13, characterized in that the line has at least two heating line sections (216, 226) which run essentially parallel to one another, the two heating line sections (216, 226) being brought together at their two ends (250, 252); the heating lines (216, 226) open into a common return line (254) at their return end (250); and the leading ends of the heating lines are arranged in the flow direction of the heating medium at the beginning of the heating lines (216, 226). 15. Heating or cooling body according to the preamble of claim 14, or one of claims 7 to 13, characterized in that the return ends (250) are arranged at the upper section of the heating or cooling body or at the rear end of the heating lines (216, 226) in the flow direction of the heating medium. 16. Heating or cooling body according to the preamble of claims 14 and 15, or one of claims 7 to 13, characterized in that the leading ends (252) are provided at the lower end of the heating body. 17. Heating or cooling body according to the preamble of claims 14 to 16, or one of claims 7 to 13, characterized in that the heating lines are combined at the return end via a T- or Y-piece or the like. 18. Heating or cooling body according to the preamble of claims 14 to 17, or one of claims 7 to 13, characterized in that at the leading end the heating lines (216, 226) are connected to the leading end of the heating or cooling system via a T- or Y-piece (252) or the like. 19. Heating or cooling body according to one of claims 14 to 18, characterized
characterized in that the return line (254) has a different cross-section than the heating line(s) (216, 226). 20. Heating or cooling body according to one of claims 14 to 20, characterized in that the area beyond the return pipe (254) including the latter and the area on this side of the return pipe differ in their respective pressure sum, consisting of the static pressure, the flow pressure and the capillary pressure.