CA3229867A1

CA3229867A1 - Stationary infrared radiator

Info

Publication number: CA3229867A1
Application number: CA3229867A
Authority: CA
Inventors: Thomas Kubler
Original assignee: KUBLER GmbH
Current assignee: KUBLER GmbH
Priority date: 2021-08-27
Filing date: 2022-08-25
Publication date: 2023-03-02
Also published as: US20240175585A1; EP4392718A1; WO2023025879A1

Abstract

The invention relates to a stationary infrared radiator (1) which is to be operated in a decentralised manner for heating buildings, comprising a reflector (2) and at least two different components (30, 40) which emit IR radiation for heating, the reflector (2) having a longitudinal axis (L) and a transverse axis (Q), which runs at right angles to the longitudinal axis (L) and parallel to the reflector, and a reflector surface (20). The first component (30) is designed as a bright radiator or as a dark radiator and has a connection for supplying fuel gas. The second component (40) is designed as an electrical resistance heater (4) having at least one heating element. The aim of the invention is to control the temperature more precisely and simultaneously to produce the infrared radiator more simply. The first component (30) and the second component (40) are respectively disposed offset from one another in a direction of the transverse axis (Q) and in a direction at right angles to both axes (L, Q) in front of the reflector surface (20).

Description

STATIONARY INFRARED RADIATOR
FIELD OF THE INVENTION
[0001]The invention relates to a stationary infrared radiator which is to be operated in a decentralized manner for heating buildings, having a reflector and at least two different components emitting IR radiation for heating, wherein the reflector has a longitudinal axis and a transverse axis extending at right angles to the longitudinal axis and parallel to the reflector, and a reflector surface. The first component is designed as a light radiator or as a dark radiator and has a connection for supplying fuel gas. The second component is designed as an electric resistance heater having at least one heating element.
The infrared radiator is preferably mounted suspended from a ceiling.
BACKGROUND OF THE INVENTION

[0002]A stationary infrared radiator which is to be operated in a decentralized manner is to be understood as a heating device, in particular for halls, which is primarily designed as a ceiling device and is directly operated using fuel gas and/or electrical energy. Such decentralized infrared radiators generate the thermal energy themselves and emit it to the environment via the respective radiating components, overwhelmingly in the form of IR radiation. They function, when driven by fuel, in a temperature range between 300 C
and 900 C and, when driven by electricity, at up to 1200 C. Fuel gas and also fuel oil are to be understood as fuels. In the case of centrally operated radiators, the thermal energy is centrally generated outside of the respective radiator and hydraulically supplied to the radiators by means of heat exchangers, in contrast to decentralized radiators.

[0003]Operating infrared radiators with a burner and indirectly in combination with electrical energy, is already known. EP 2 492 600 B1 describes heating the combustion air with the aid of solar energy before introducing it into the burner, wherein electrical energy is also used in addition to thermal energy.

[0004] EP 3 239 616 B1 describes a system of an infrared radiator, in which the radiant tube is produced from stainless steel and is heatable both using fuel gas and also using an electric resistance heater.

[0005] DE10 2009 021158 Al describes the basic design of an infrared radiator with a reflector designed as a housing with a reflector surface and with an additional tube 1386-1180-9800.1 reflector arranged between the radiant tube and the reflector surface. An alternative design of a generic infrared radiator is known from DE10 2012 025299 Al, in which a reflector is accommodated by a separate housing and additional tube reflectors are also provided. The respective reflector forms a hood for the warm air generated by the infrared radiators. According to CN 203 605 313 U, a floor unit is known, in which a gas heating device and an electric heating device are combined.
SUMMARY OF THE INVENTION

[0006] The underlying object of the invention is to design an infrared radiator, which may be operated using different energy media, and arrange it in such a way that it may be more precisely controlled as a ceiling unit with respect to its temperature and is simultaneously easier to produce.

[0007] The problem is solved according to the invention in that the first component and the second component are arranged in front of the reflector surface offset from one another in a direction of the transverse axis and/or the first component and the second component are arranged in front of the reflector surface offset from one another in a direction perpendicular to the longitudinal axis and/or in a direction perpendicular to the transverse axis. The preferred solution is also included in this solution, that the first component and the second component are respectively arranged in front of the reflector surface offset from one another in a direction of the transverse axis and in a direction perpendicular to the longitudinal axis and to the transverse axis.

[0008] Due to the offset and during pure electrical operation, the electric heating element partially heats the component of the dark or light radiator provided for emitting. The dark radiator preferably forms an exhaust gas pipe, functioning as a radiant tube, for combusting the fuel gas. In particular in the case of dark radiators, the radiant energy of the electric heating element, captured or absorbed by the exhaust gas pipe designed as a radiant tube, is discharged or emitted again as radiant heat. Since the dark radiator or light radiator is likewise completely located under the reflector, the so-called shading of the electrically-generated IR radiation thus does not negatively impact the radiation factor or the efficiency of the infrared radiator. The advantage of the shading is significant in the case of power adjustment by means of pulse width modulation of the electric heating element. In this case, the mass of the dark radiator or light radiator results in additional 1386-1180-9800.1 inertia, which results in a favorable equalization of the temporal radiation profile. The advantage according to the invention is greater due to the design and geometry used in dark radiators than for light radiators. Another advantage which supports this effect is the convection trough usually formed by the reflector or the hood of the reflector, in which the warm air collects and thus prevents any convection losses due to shadowing.

[0009] Regardless of the advantage for pulse width modulation, the structural separation of the radiant tube or incandescent body for the fuel gas energy medium from the resistance heater for the electrical energy medium achieves that the radiant temperatures may be controlled in a targeted way for each medium in isolation. Due to the structural separation, the respective surface temperatures do not substantially influence each other in bivalent operation of the infrared radiator, thus when it is heated with fuel gas and simultaneously with electricity. With respect to the relevant prior art, the necessity of electrical insulation of the radiant tube is thereby eliminated as well as the processing of stainless steel for the radiant tube.

[0010]According to the invention, the method for operating an infrared radiator is also advantageous, in which the radiant tube captures the radiation energy of the electric heating element through absorption and the mass inertia of the radiant tube is used for equalizing the temporal radiation profile of the infrared radiator in the case of pulse width modulation of the electric heating element. The radiant tube causes a shadow for the radiation of the heating element or a shading of the electrically-generated IR
radiation, which is advantageously exploited.

[0011] It may also be hereby advantageous if both components are attached to the infrared radiator structurally separated or independently from one another.
Each component may thus be designed and installed in isolation, without having to take structural features of the respective other components into consideration. The infrared radiator has a mounting, which is designed, for example, as a reflector, housing, and/or as a bulkhead, wherein the respective components are attached to the mounting.

[0012] It may be further advantageous if a separate tube reflector is provided between the reflector and the component. Due to the tube reflector, it is possible to set the radiation sector and the radiation direction of the respective component with respect to efficiency and shading. For this purpose, the surface of the tube reflector may have different radii 1386-1180-9800.1 of curvature and an asymmetry relative to the respective component. The reflector is designed as double-walled and reflects the IR radiation emitted by all components. An outer wall extending parallel to the reflector is provided on the side of the reflector opposite the reflector surface and is insulated from the reflector by an air gap. With regards to efficiency, it may be advantageous if insulation is provided between the reflector and the tube reflector. By this means, the amount of radiation reflected by the tube reflector is optimized with respect to the pure air gap insulation.

[0013] With respect to the electrical component, it may be advantageously provided that the heating element has a heating spiral which is sheathed with a metallic and/or ceramic sheath. The two materials are generally used in alternation. It has been shown that the advantage of pulse width modulation may be used for both types of heating elements, thus for those made from metal and those made from ceramic. As an alternative to a surrounding, symmetrical sheath, the heating spiral may be meander-shaped or in strips laid adjacent to one another, embedded into a metallic and/or ceramic material or sheathed by the same.

[0014] It may be advantageous for the further improvement of efficiency if insulation is also provided between the heating element and the reflector. In the case of use without a separate tube reflector, the proportion of radiation directed upward or behind the heating element is minimized by this means in favor of the proportion of radiation directed downward or forwards. This advantage may be used both for ceramic heating elements and also for heating elements with a metallic sheath. With respect to a simple design, it may be advantageous is if the heating element is mounted on the reflector. The reflector thereby functions as a supporting component, and a connection for the heating element through the reflector into a supporting housing, which is present behind the reflector, may be thus omitted.

[0015] It may be further advantageous for the pulse width modulation if the first component is designed as a dark radiator, has a burner for fuel, and has at least one exhaust gas pipe coupled to the burner and designed as a radiant tube. The exhaust gas pipe forms a very good buffer for absorbing the radiation emitted by the heating element, and the exhaust gas pipe has a very good property of redischarging or reemitting this 1386-1180-9800.1 absorbed radiation. In addition to the material property, the large surface and the large mass of an exhaust gas pipe are decisive for the advantage of being used as a buffer.

[0016] It may be advantageous for the operation of an infrared radiator with fuel if a suction fan is arranged at the end of the exhaust gas pipe so that the exhaust gas pipe connects the burner to the suction fan. The fuel does not flow freely into the exhaust gas pipe and completely combusts in the exhaust gas pipe.

[0017] It may be advantageous for a dark radiator if the exhaust gas pipe has at least one linearly-extending section or at least two linearly-extending sections coupled via a connecting tube deflecting the exhaust gas flow, wherein the linearly-extending sections are arranged on the reflector parallel to the longitudinal axis. The course of the exhaust gas pipe is largely dependent of the geometry of the flame, which is also controlled by the suction fan.

[0018] As an alternative to a dark radiator, it may be advantageous if the first component is designed as a light radiator, has at least one incandescent body, and has a connection for supplying fuel gas to the incandescent body. Such heat sinks, preferably produced from ceramic, form a very large surface for the fuel and may also have catalytic properties.

[0019] The combination of electrical components with components that are operated with fuel has the advantage that the infrared radiator only has one electrical connection which is provided to supply and/or control all components. Correspondingly, the addition of a second component does not necessitate an increase in installation costs.

[0020] It may be advantageous for a dark radiator if the reflector is placed on at least two bulkheads arranged parallel to the transverse axis, wherein the bulkheads have attaching points for suspending the infrared radiator. At the same time, the bulkheads have multiple recesses which function as mounts for the exhaust gas pipe.

[0021] It may be advantageous with regard to versatility if at least one electrical ceiling light with a light source is provided as a working light, connecting to the reflector surface in at least one direction of one of the axes or connecting to the reflector in at least one direction of one of the axes. The present installation, in the form of electrical cables and supports for the infrared radiator, may be simultaneously used for lighting due to this type of integrated ceiling light.
1386-1180-9800.1

[0022] It may also be advantageous if the connection is designed for three-phase alternating current and the same number of heating elements and/or light sources are connected to each phase of the connection. A uniform network load is achieved in this way.

[0023]With regard to a simpler production, it may be of particular significance for the present invention if a common control unit is provided to control the two components and the two components may be selectively controlled independently from one another or simultaneously with one another.
BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Further advantages and details of the invention are explained in the patent claims and in the description and depicted in the figures. As shown in:

[0025] Fig. 1 is a sectional view perpendicular to the longitudinal axis of an infrared radiator having an electric heating element made from metal and a dark radiator operated with fuel gas;

[0026] Fig. 1a is an electric heating element with a sheath made from metal symmetrically encircling the heating spiral;

[0027] Fig. 2 is a sectional view perpendicular to the longitudinal axis of an infrared radiator having an electric heating element made from ceramic and a dark radiator operated with fuel gas;

[0028] Fig. 3 is a sectional view of an infrared radiator having an electric heating element made from metal and an electric heating element made from ceramic and a dark radiator to be operated with fuel gas;

[0029] Fig. 4 is a sectional view of an infrared radiator through a bulkhead;

[0030] Fig. 5 is a view from below of an infrared radiator according to Fig.
1;

[0031] Fig. 6 is a view from below of an infrared radiator according to Fig.
2;

[0032] Fig. 7 is a sectional view in the direction of the longitudinal axis of an infrared radiator according to Fig. 6;

[0033] Fig. 8 is a schematic diagram of an infrared radiator in a view from below.
DETAILED DESCRIPTION OF THE INVENTION

[0034] For reasons of clarity, the respectively identical components depicted in the following figures are not consistently numbered. The respective reference numeral of a 1386-1180-9800.1 certain component may be determined from the respective first figure of a certain view.
These are essentially Figs. 1, 5, and 7.

[0035] Numerous details of an infrared radiator 1 are depicted in a sectional view in Fig.
1. The central design component is an air-gap insulated reflector housing, which is formed from a trapezoidal reflector 2 having an inner reflector surface 20 and an outer wall 23 spaced apart by an air gap 10. Reflector 2 and outer wall 23 are connected to one another via webs 11.

[0036] Reflector 2 forms a hood 26, closed at the top, in which multiple components 30, 40 are arranged to generate heat in the form of infrared radiation. Air gap 10 is accessible via holes 29 in reflector 2, so that air may be extracted from hood 26 via air gap 10 and supplied to a burner 3 (Fig. 7). Reflector 2 lies on a bulkhead 25, depicted in figure 4 in cross section, which has tabs 27 for suspension. A housing 24, which functions to accommodate the technology and, as depicted in Figs. 5-7, may be designed as a lighting housing 5 for accommodating a ceiling light 50, is connected on both sides, respectively at the ends of reflector 2.

[0037] In all exemplary embodiments, a component for heating, designed as radiant tube 30, is identically positioned underneath reflector 2 for heating. Radiant tube 30 functions to supply and combust fuel gas and has two sections Al and A2 (Fig. 8) extending parallel in the direction of longitudinal axis L. An additional tube reflector 21, which reflects the infrared radiation more precisely and also more focused than reflector surface 20, is provided between radiant tube 30 and reflector surface 20 for each of the two radiant tubes 30. Insulation 6 is incorporated between tube reflector 21 and reflector 2.

[0038] A second component for heating is provided in the form of an electric resistance heater 4. This comprises three heating elements 40 extending in the direction of longitudinal axis L, which have a heating spiral 41 with a metallic sheath 42, depicted in greater detail in Fig. 1 a. An additional tube reflector 22, which reflects the infrared rays more precisely and also more focused than reflector surface 20, is also provided here in front of reflector surface 20 and above heating element 40. The efficiency may also be increased here by additional insulation 6.

[0039] Electric resistance heater 4 is arranged centered and above the two sections of radiant tube 30. Electric resistance heater 4 is thereby likewise offset in the direction of 1386-1180-9800.1 transverse axis Q with respect to radiant tube 30 as well as offset above in the vertical direction perpendicular to transverse axis Q. Due to this offset, radiant tube 30 lies in the radiation sector of heating element 40, which is depicted with dashed lines on the left side for a heating element 40 by way of example. This always creates a radiation shadow, regardless of whether radiant tube 30 is colder or warmer than heating element

40.
[0040]According to Fig. 2 and as an alternative to heating elements 40 made from metal, heating elements 40 are provided with a sheath 42 made from ceramic, in which heating spiral 41 is embedded. Due to the larger surface of ceramic heating element 40, in contrast to heating element 40 made from metal, insulation 60 is incorporated between ceramic heating element 40 and tube reflector 22. A radiation shadow is also created by ceramic heating element 40, which is depicted by way of example for the left section of radiant tube 30.

[0041]A combination of metallic and ceramic heating elements 40 in conjunction with a dark radiator is depicted in Fig. 3. In this exemplary embodiment, ceramic heating elements 40 are positioned laterally on the flanks of reflector 2.

[0042]According to all depicted exemplary embodiments and regardless of the selection of the material for electric resistance heater 4, an offset to radiant tube 30 is provided, which according to the invention enables a simple power adjustment using pulse width modulation of the electric heating elements together with an independent assembly.

[0043]As is clear in Fig. 4, two recesses 28 for mounting radiant tube 30 are provided in bulkhead 25 together with three recesses 28 for three heating elements 40 made from metal.

[0044]According to the view from below according to Fig. 5, the exemplary embodiment according to Fig. 1 is depicted with heating elements 40 made of metal, which extend symmetrically centered to two straight sections Al and A2 of radiant tube 30.
Two sections Al and A2 of radiant tube 30 are flow technically connected to one another via a connecting tube 32 at their end opposite burner 3. The two exemplary embodiments according to Figs. 5 and 6 are structurally identical, except for the type of heating elements 40, and are equipped with ceiling lights 50. For this purpose, a lighting housing 5, by means of which reflector 2 is increased in length, is connected on both sides to reflector 2 in the direction of longitudinal axis L. Lighting housing 5 terminates, as is 1386-1180-9800.1 indicated in Fig. 7, with a light permeable cover 52 facing downward. A light source 51 is provided in lighting housing 5 behind cover 52 as a working light with a luminous flux of at least 5,000 lumens and up to 150,000 lumens.

[0045] In the exemplary embodiment according to Fig. 7, housing 5 functions simultaneously to accommodate burner 3, suction fan 31, and flame pipe 33 and as the lighting housing. It is clear in the sectional view that this technology is accommodated in left lighting housing 5. The flame is introduced into radiant tube 30 via flame pipe 33 connecting to burner 3. With the aid of suction fan 31, the flame and the exhaust gas are suctioned out of radiant tube 30, which likewise functions as an exhaust gas pipe. Light source 51 and cover 52 are provided in lighting housing 5 underneath the technology.
The convection of the warm air out of hood 26 is curbed by the extension reflector 2 in the direction of longitudinal axis L on both sides. This is indicated by dashed arrows, which show that the warm air, which exits downward from hood 26, may not flow upward due to the two lighting housings 5. It is simultaneously possible to extract the warm air, which is generated by light source 51 and which circulates in lighting housing 5 as indicated by a dashed arrow, and supply it to the burner as combustion air.
This is achieved by air gap 10 between reflector 2 and outer wall 23, which functions as an air duct. The flow for the extracted air in the air duct is graphically indicated with arrows in Fig. 1 and 5 and also in Fig. 7. Aside from the warm air from lighting housing 5, the warm air exiting laterally from hood 26 is also extracted via holes 29 and supplied to burner 3 via air duct 10.

[0046]Additional exemplary embodiments are sketched in Fig. 8, in which reflector 2 is enlarged by variously arranged and dimensioned lighting housings 5 and the convection is curbed by these means. One first possibility is to arrange further lighting housings 5 on one side in the direction of longitudinal axis L or, as indicated with dashed lines, on both sides parallel to longitudinal axis L, such that reflector 2 is also increased in its width, that is, in the direction of transverse axis Q. In addition, lighting housing 5 might also be designed as a module 54 and attached to or plugged on to already present housing 24 or to a first lighting housing 5. The electrical supply for controlling and for light source 51 is provided during the attachment to or plugging on to by corresponding contacts (not depicted in greater detail) between the modules and lighting housing 5 or housing 24. A
1386-1180-9800.1 further possibility provides for arranging reflector 2 and the technology in a common housing 24 and also for mounting both ceiling lights 50, which are provided on both sides in the direction of longitudinal axis L, in this common housing 24.
1386-1180-9800.1 List of reference numerals 1 Infrared radiator Air gap 11 Webs 2 Reflector Reflector surface 21 Tube reflector 22 Tube reflector 23 Outer wall 24 Housing Bulkhead 26 Hood 27 Tabs 28 Recesses 29 Holes 3 Burner Component/Radiant tube/Exhaust gas pipe 31 Suction fan 32 Connecting tube 33 Flame pipe 4 Electric resistance heater Heating element 41 Heating spiral 42 Sheath 5 Lighting housing Ceiling light 51 Light source 52 Cover 54 Module 6 Insulation 1386-1180-9800.1 60 Insulation Al Section A2 Section L Longitudinal axis Q Transverse axis 1386-1180-9800.1

Claims

- 13 -

1. A stationary infrared radiator (1) which is to operate in a decentralized manner for heating buildings, having a reflector (2) and at least two different components (30, 40) which emit IR radiation for heating, wherein b) the reflector (2) has a longitudinal axis (L) and a transverse axis (Q) which runs at right angles to the longitudinal axis (L) and parallel to the reflector (2), and a reflector surface (20), c) the first component (30) is designed as a light radiator or as a dark radiator and has a connection for supplying fuel gas, d) the second component (40) is designed as an electric resistance heater (4) having at least one heating element, characterized in that the first component (30) and the second component (40) are arranged in front of the reflector surface (20) offset from one another in a direction of the transverse axis (Q) and/or the first component (30) and the second component (40) are arranged in front of the reflector surface (20) offset from one another in a direction perpendicular to the longitudinal axis (L) and/or in a direction perpendicular to the transverse axis (Q).

2. The infrared radiator (1) according to claim 1, characterized in that the two components (30, 40) are attached to the infrared radiator (1) structurally separated or independently from one another.

3. The infrared radiator (1) according to claim 1 or 2, characterized in that a separate tube reflector (21, 22) is provided between the reflector (2) and the component (30, 40), or a separate tube reflector (21, 22) is provided between the 1386-1180-9800.1 reflector (2) and the component (30, 40) wherein insulation (6) is provided between the reflector (2) and the tube reflector (21, 22).

4. The infrared radiator (1) according to one of the preceding claims, characterized in that insulation (60) is provided between the heating element (40) and the reflector (2), and/or the heating element (40) is mounted on the reflector (2).

5. The infrared radiator (1) according to one of the preceding claims, characterized in that the first component (30) is designed as a dark radiator, has a burner (3) for fuel, and has at least one exhaust gas pipe coupled to the burner and designed as a radiant tube.

6. The infrared radiator (1) according to claim 5, characterized in that a suction fan (31) is arranged at the end of the exhaust gas pipe (30) so that the exhaust gas pipe (30) connects the burner to the suction fan (31).

7. The infrared radiator (1) according to one of preceding claims 5 or 6, characterized in that the exhaust gas pipe (30) has at least one linearly-extending section (A1) or at least two linearly-extending sections (A1, A2) coupled via a connecting tube (32) deflecting the exhaust gas flow, wherein the linearly-extending sections are arranged on the reflector (2) parallel to the longitudinal axis (L).

8. The infrared radiator (1) according to one of the preceding claims 1 to 7, characterized in that the first component (30) is designed as a light radiator, has at least one incandescent body, and has a connection for supplying fuel gas to the incandescent body.

9. The infrared radiator (1) according to one of the preceding claims, characterized in that the infrared radiator (1) has an electrical connection which is provided to supply and/or control all components (30, 40).

10. The infrared radiator (1) according to one of the preceding claims, characterized in that the reflector (2) is placed on at least two bulkheads (25) arranged parallel to the transverse axis (Q), wherein the bulkheads (25) have attachment points for suspending the infrared radiator (1).
1386-1180-9800.1

11 . The infrared radiator (1) according to one of the preceding claims, characterized in that at least one electric ceiling light (50) with a light source (51) is provided as a working light, connecting to the reflector surface (20) in at least one direction of one of the axes (L, Q) or connecting to the reflector (2) in at least one direction of one of the axes (L, Q).

12. The infrared radiator (1) according to one of the preceding claims, characterized in that the connection is designed for three-phase alternating current and the same number of heating elements (40) and/or light sources (51) are connected to each phase of the connection.

13. The infrared radiator (1) according to one of the preceding claims, characterized in that a common control unit is provided to control the two components (30, 40) and the two components (30, 40) are selectively controllable independently from one another or simultaneously with one another.

14. A system comprising multiple infrared radiators (1) according to one of the preceding claims, and lines for fuel and electrical cable for supplying the infrared radiator (1), and a ceiling device (6) for attaching the infrared radiator (1) and for attaching the lines and the cable.

15. A method for operating an infrared radiator (1) according to one of the preceding claims, characterized in that the radiant tube (30) is positioned in such a way that it absorbs radiation energy from the electric heating element (40) through absorption, and the mass inertia of the radiant tube (30) is used for equalizing the temporal radiation profile of the infrared radiator (1) in the case of pulse width modulation of the electric heating element (40).
1386-1180-9800.1