WO2022161796A1

WO2022161796A1 - Infrared heating device, method for operating an infrared heater, and space heater

Info

Publication number: WO2022161796A1
Application number: PCT/EP2022/050821
Authority: WO
Inventors: Hans-Jürgen Koch
Original assignee: Bioheatplus Gmbh
Priority date: 2021-01-29
Filing date: 2022-01-17
Publication date: 2022-08-04
Also published as: DE102021102056A1

Abstract

The invention relates to an infrared heating device (1), comprising a housing (2) with a front opening (3), an emission grate (4), which can be fastened to the housing (2), so that the front opening (3) can be covered, a plurality of infrared planar emitters (5), which are formed with a ceramic cavity construction and have a power per unit area of 20 to 35 kW/m2, a frame (9) made of light-reflecting material, in which frame the plurality of infrared planar emitters (5) can be held, a thermal insulation layer (10), which can be installed at least partly between the housing (2) and the frame (9), and a control unit (11) for the pulsed operation of the plurality of infrared planar emitters (5), wherein specific measures for an energy-efficient and fast heating process are proposed.

Description

Infrared heater, method of operating an infrared heater and space heater

The invention relates to an infrared heater, in particular an infrared heater that is suitable for space heating in buildings with living or working spaces.

As part of the current efforts to increase energy efficiency, new heating systems are constantly being presented. Due to an increasing proportion of available renewable energies, electricity-based heating systems are also increasingly being considered. Depending on the application, infrared heaters in particular can ensure lower energy requirements compared to other heating systems due to the direct radiation they emit.

Currently known infrared surface heating systems, which are attached to a wall of a room, for example in the manner of pictures, can heat a room over a large area, but only with a low heat output. They also take up a lot of space that would otherwise be used for pictures, cupboards, etc.

Smaller infrared heaters are also known, which are portable, for example. These are used for focused heating of smaller areas.

With a view to space heating, it is particularly important that such a power-based infrared heating system achieves good results under realistic conditions in terms of energy efficiency and taking user comfort into account.

Furthermore, it must also be taken into account that the production, assembly and integration into a heating management system must be simple. This applies in particular to retrofitting and replacing night storage heating systems or heating systems that run on fossil fuels. The object of the present invention is to at least partially alleviate the problems described with reference to the prior art. In particular, a compact infrared heating device is to be specified which can heat a room particularly efficiently and also meets high standards with regard to manufacturing costs and operational reliability. Furthermore, an operating method for an infrared heater is to be specified, which results in improved heating behavior.

These objects are achieved with an infrared heating device and an operating method according to the independent claims. Advantageous developments are specified in the dependent claims. It should be pointed out that the description, in particular in connection with the figures, shows further developments which name further embodiment variants of the invention. The features of the claims can be combined with one another as well as with features of the description.

An infrared heater contributes to this, which has at least one housing, a radiation grid, a plurality of infrared surface radiators, a housing, a thermal insulation layer and a control unit for operation.

The case is provided with a frontal opening, which is made of plastic comprising polyphenylene sulfide (PPS) with a mineral additive. The housing can be designed as a one-piece injection molded component, for example in the manner of a formed and/or shell-like housing wall. It is possible that the case is made entirely of PPS material with additive. It is possible for the mineral additive to be fibres, for example glass and/or carbon fibres. The proportion of the filler material can be more than 30% by weight, possibly also at least 40% by weight. The housing can be designed with a flame retardant applied and/or integrated in the material. The temperature resistance of the material of the housing is preferably at least 180°C, in particular at least 220°C or even at least 250°C. The preferred one-piece housing can form a kind of rear wall, which thus (with the exception of small through holes and mounting recesses) is closed and has only a single large opening, which forms the front. The opening is designed in such a way that the components to be integrated can be easily installed and a significant proportion of infrared radiation can be emitted through it during operation.

The radiation grille is formed with aluminum and can be fastened or fastened to the housing so that the front opening can be covered or covered. A grid is understood here as a component which divides the large opening of the housing into many small opening segments. The radiation grating can be made in one piece or with several elements together. It can be expedient to subdivide the opening with a regular grid, so that, for example, opening segments of the same type or size are formed at least in certain areas. In the installed state, the radiation grid is exposed to a major part of the emitted infrared radiation, so that it should be designed and arranged to be temperature-resistant. The radiation grille is preferably dimensionally stable and z. B. suitable to form a stiffening connection with the housing, e.g. in the manner of a tongue and groove connection or click connection. It is possible for the radiation grille to be essentially made entirely of aluminum, possibly with the addition of a color or coating.

Furthermore, a plurality of infrared panel radiators are provided, which are formed with a ceramic cavity construction. The infrared surface heaters are designed with a (structured or primary) surface aligned towards the radiation grille. The cavity of the infrared panel heater is filled with thermal insulation and the area output of an infrared panel heater is in the range from 20 to 35 kW/m ² [kilowatts per square meter]. There can preferably be 2, 3, 4, 5 or 6 infrared panel heaters be provided. The emitted infrared radiation is preferably in the wavelength range from 2 to 10 pm [micrometers]. In particular, these are surface radiators that reach a surface temperature in the range from 550° C. to 650° C. during normal operation. The interpretation of the ceramic cavity construction is preferably such that a surface temperature of 400°C is reached after approx. 3 to 4 minutes. It is possible that all infrared surface heaters are identical. It is possible that the infrared panel heater includes an integrated thermocouple (NiCr-Ni).

Furthermore, the frame made of light-reflecting material is provided, in which the plurality of infrared surface radiators can or is accommodated. The enclosure can form a receiving space for the mounted infrared panel radiators. The shape of the bezel may substantially correspond to the shape of the housing. The enclosure can be a single, dimensionally stable component. The infrared panel radiators are arranged between the frame and the frontal opening, so that the rear paneling can also be used to deflect infrared radiation emitted by the infrared panel radiators not directly towards the frontal opening towards this frontal opening. The enclosure can therefore be designed in the manner of a hollow mirror. It is also possible that the bezel contributes to rapid heat distribution in the housing, so that the formation of so-called hotspots can be avoided.

The thermal insulation sheet is at least partially attachable between the housing and the bezel. The thermal insulation layer or its material can, for example, withstand a temperature load of at least 1,000° C., in particular at least 1,200° C. (permanently). The thermal insulation layer is preferably thin-walled, e.g. with a material thickness of up to a maximum of 8 mm, in particular approx. 6 mm. The thermal insulation layer can be made of ceramic fiber paper. The thermal insulation layer can adapt well to the shape of the housing and/or the enclosure. The thermal insulation layer has the particular task of protecting the housing from the temperatures inside.

Finally, a control unit is provided for clocked operation of the plurality of infrared surface radiators, clocking being carried out with an associated bimetallic switch which has a switching temperature above 125°C. The control unit is arranged outside the housing, but preferably on this Housing. The control unit controls the electrical and electronic components of the infrared heater. It may include a microprocessor, data storage, comparator, etc. The infrared heater is operated in cycles, with the infrared panel heaters being energized until the bimetallic switch has reached its (off) switching temperature, i.e. in this case a switching temperature above 125°C, preferably in the range from 130°C to 150°C , very preferably about 140°C. When the bimetallic switch (or the infrared panel heater) cools down again (eg by at least 20 or 20 to 45°C), it automatically switches the power supply on again, and so on. For this purpose, the bimetallic switch can have a temperature sensor inside the housing, for example on the housing (behind the infrared surface radiators).

The plurality of infrared surface radiators can be mounted in the enclosure non-parallel or at least partially inclined to one another. This means in particular that not all infrared panel heaters emit infrared radiation in (only) one or (only) the same direction over the frontal surface. It is possible for at least one (central) infrared surface radiator to be arranged parallel to the opening and further infrared surface radiators (located at the edge) to be inclined and/or curved. This allows the overall radiation behavior of the infrared panel heaters to be adjusted, e.g. to form heat spots, targeted heat distribution or similar. In addition, it can result in a more space-saving arrangement of the infrared panel heaters.

The radiation grille can be designed with struts, which realize an openness of at least 50% with regard to the frontal opening and/or are formed with reflector surfaces with which the infrared radiation of the infrared surface radiators is deflected at an angle when it leaves the housing. The openness can be described as the proportion of the opening of the housing that is not covered by the radiation grating in relation to the frontal opening as a whole. The openness also describes the extent to which you can look inside the housing. The openness is preferably at least 60%. Openness may need to be limited to 80% to avoid structural and/or thermal aspects are not adversely affected. The struts can be made from an extruded aluminum profile material. They can be designed with a bevel, an inclined impact surface, etc. for the infrared radiation (in the manner of reflector surfaces), which enable the infrared radiation to be deflected. These reflector surfaces are preferably provided in the outermost area relative to the housing or the infrared surface radiators. When the infrared heating device is in the installed state, the reflector surfaces are preferably located at least partially outside the housing, so that infrared radiation that strikes there is nonetheless largely emitted into the environment.

A single bezel formed with an aluminum sheet body may be provided. The aluminum sheet body can be designed as a stamped and bent component to which other components of the infrared heating device, such as the infrared surface heaters, can or are attached.

A single layer of thermal insulation may be provided covering at least 85% of a contact area of the bezel and housing. A contact surface is understood to mean in particular the direct contact surface of the enclosure on the housing, which arises when the two are joined together in the desired manner without a thermal insulation layer.

Electrical and/or electronic connections of components in the housing can be routed at least partially through the housing, the thermal insulation layer and the housing and end in a rear chamber with a chamber wall, the control unit also being at least partially arranged in the chamber. The connections serve in particular to transport electricity and/or data. These can be implemented with cables. The preferably one-piece chamber wall can form the chamber together with the housing to which it is attachable or attached. The energy and/or data connection of the control unit to external sources can be established via a central connection provided on the chamber wall and/or an antenna. According to another aspect, a method for operating an infrared heating device is proposed, at least comprising the following steps: a) clocked activation of the plurality of infrared surface radiators over a start-up period (H1); b) deactivating the plurality of infrared panel radiators for a first pause period (P1); c) Carrying out a phase change heating, comprising heating phases (Hp) with clocked activation of the plurality of infrared surface radiators and pause phases (Pp) with deactivated plurality of infrared surface radiators, with at least one heating phase being shorter in time than the start-up period (H1).

The specified steps a), b) and c) are preferably carried out in chronological (immediate) succession.

In step a), all infrared panel radiators can be activated at the same time or, if necessary, at different times. The heat output can be specified individually / differently or equally for all infrared surface heaters. Step a) is carried out in particular when the heating process starts. The start-up period is preferably at least 15 minutes, in particular at least 25 minutes. The start-up period should preferably not exceed 40 minutes. The start-up period is particularly preferably about 30 minutes.

Once the start-up period has been reached, step b) is initiated automatically, here too preferably simultaneously for all infrared panel radiators. The first pause period is preferably in the range of 4 to 7 minutes, in particular about 5 minutes.

This is followed by the phase change heating step - if the desired room temperature has not yet been reached. This can include one or more heating phases and also at least one pause phase. The number of phases can vary with regard to the difference between the current and desired room temperature. The heating phases and/or pause phases can vary in time and/or be designed differently. In simple applications it is preferred to assign specific or fixed time periods to each of the heating phases and pause phases. A (or each) heating phase can last for less than 20 minutes, in particular in the range from 15 to 18 minutes. A pause phase can last for a period of less than 5 minutes, in particular in the range from 4 to 5 minutes, in particular around 4:30 minutes.

It can be provided that in step c) one (or each) pause phase (Pp) is shorter in time than the first pause period (P1).

Step a) can be carried out if a temperature in the vicinity of the infrared heating device can be determined or is determined, which is below a specifiable comfort temperature. The ambient temperature can be determined or calculated using an external temperature sensor. This information can be made available to the control unit, which compares it with a present comfort temperature (in particular the setpoint temperature specified by the user). Step a) can be initiated (automatically) in particular after a new adjustment of the comfort temperature and/or a predetermined minimum difference between the current ambient temperature and the comfort temperature.

The method can be ended (automatically) when a predefinable comfort temperature has been reached in the vicinity of the infrared heater.

According to a further aspect, a space heater comprising at least one infrared heater is proposed, which is attached to or in a room wall at a definable distance from the floor of the room, with (at least) one temperature sensor for the room temperature and/or (at least) one Adjusting member is installed for a comfort temperature in the room, which are connected to the control unit of the infrared heater in a data-conducting manner.

The space heating can include a plurality of infrared heaters, which may emit infrared radiation in the same direction and/or at least partially on top of each other. The infrared heaters can be in/at opposite corners and/or Be arranged room walls of a room. The provision of at least one infrared heater per 10 m ² [square meters] of room floor is preferred, with each infrared heater having a heat output of at least 1,000 watts.

The infrared heater should preferably be positioned in the upper half of the room, for example at a distance of at least 1.60 m from the floor of the room, preferably at a distance of about 1.80-2.20 m.

A temperature sensor for measuring the current room temperature and a setting element (e.g. rotary control, keypad, touch pad, mobile phone, etc.) for a user-desired comfort temperature can be provided mobile or fixed in the room. It is possible for both components to be housed in one housing, but this is not absolutely necessary. If these components are permanently installed in the room, they are preferably at a distance of approx. 1.40 - 1.70 m from the floor of the room.

The temperature sensor and/or setting element can be connected to the control unit of the infrared heating device by cable and/or using radio technology (WLAN, Bluetooth®, etc.).

At least one infrared heater can be attached to the wall of the room and/or the radiation grid can be designed in such a way that a significant proportion of the infrared radiation leaving the infrared heater is emitted towards the floor of the room. Consequently, an infrared heater may be mounted at an angle to the floor of the room as a whole (e.g. at an angle of 15-30° to the horizontal). It is also possible for the radiation grid to be designed with the reflector surfaces described above, in order to set this effect with horizontally aligned built-in infrared heaters. The significant proportion preferably comprises at least 20%, in particular at least 30-60% of the emitted infrared radiation.

A space heater is expedient, with at least one infrared heater being detachably plugged into a frame which is fastened to at least one wall of the room and is provided with at least a top cover and a bottom cover. The (preferably rectangular) frame can be made with stainless steel profiles and attached to the room wall or ceiling. The frame encloses the infrared heater, which is preferably inserted from the front and can then be connected to the frame (eg with a click connection). Spaces behind the infrared heater located in the frame can be closed off by covers (top, bottom and/or lateral, possibly plate-shaped). If necessary, the frame can be fastened to two adjacent room walls at a corner.

In addition, a computer program is proposed which is set up to carry out a method proposed here.

The facts and functions explained with reference to the devices can also be used to characterize the method and vice versa.

The invention and the technical environment will now be explained in more detail with reference to figures. It should be noted that the figures are exemplary and are not intended to limit the subject matter of the invention. Combinations of features shown in the figures are not mandatory, unless this is explicitly pointed out here; therefore all other features can be extracted from it and combined with other features of the description or figures.

They show schematically:

Fig. 1: a front view of an infrared heater,

Fig. 2: a sectional view through an infrared heater,

Fig. 3: a detail of a radiation grid of an infrared heater,

Fig. 4: a structure of a space heater, and Fig. 5: A diagram of an operating method for an infrared heater.

1 shows a front view of an infrared heating device 1 with a radiation grid 4 which has a plurality of horizontal struts 13 . Behind this is the housing forming the opening 3 with the infrared surface radiators 5 and the frame 9 arranged therein, which are clearly visible in this view due to the openness of the radiation grid 4 by at least 50%.

2 schematically illustrates a possible structure of an infrared heating device 1 in section, with the rear area facing the room wall being shown at the top and the frontal area of the infrared heating device being shown at the bottom.

Shown is a housing 2 with the frontal opening 3, which is formed with plastic comprising polyphenylene sulfide (PPS) with a mineral additive. This housing 2 represents the rear wall for the interior of the infrared heater 1.

A radiation grating 4 made of aluminum is fastened to the front of the housing 2 so that the front opening 3 is covered or spanned. The radiation grating 4 protrudes (with a collar) both frontally and laterally beyond the housing 2, but also rests at least partially on the inside of the housing 2 or the opening 3 in order to enter into a non-positive and/or positive connection there.

(Three) infrared surface radiators 5 are also provided, which are formed with a ceramic cavity construction. Each infrared surface radiator 5 has a (structured, essentially rectangular) surface 6 directed towards the emission grid 4 . Cavities 7 of the infrared surface radiator 5 are filled with thermal insulation 8 . The surface output of an infrared surface radiator 5 is in the range from 20 to 35 kW/m ² . The infrared surface radiators 5 are not mounted parallel or partially inclined to one another in the frame 9 . A frame 9 made of light-reflecting material is provided rearwardly adjacent to the infrared panel radiators 5, in which the plurality of infrared panel radiators 5 are accommodated. In this case, the enclosure is designed in the manner of an aluminum sheet body 17 .

In addition, a single thermal insulation layer 10 is provided (in the contact surface 18) which is arranged between the housing 2 and the bezel 9.

A chamber 20 with a chamber wall 21 is also mounted at the rear of the housing 2 . A control unit 11 for clocked operation of the plurality of infrared surface radiators 5 is provided in the chamber 20, the clocking being carried out with an associated bimetallic switch 12 attached to the inside of the frame 9, which has a switching temperature above 125°C.

All electrical or electronic connections 19 of components 5, 12 in the housing 2 are led through the frame 9, the thermal insulation layer 10 and the housing 2 and open into the rear chamber 20 in which the control unit 11 is arranged.

3 shows a detail of an embodiment variant of the radiation grating 4. The radiation grating 4 is designed with struts 13 which form reflector surfaces 14, with which the infrared radiation 15 of the infrared surface radiator 5 is deflected at an angle 16 when it leaves the housing 2.

4 schematically discloses an embodiment of a space heater 23 with (example) an infrared heating device 1 which is fastened on or in a room wall 26 at a definable distance 24 from the floor 25 of the room. A temperature sensor 27 for the room temperature and an adjustment element 28 for a comfort temperature in the room 29 are (permanently) installed remote from the infrared heating device 1 and are connected to the control unit 11 of the infrared heating device 1 in a data-conducting manner. The installation is carried out in such a way that a significant proportion of the infrared heater 1 leaving infrared radiation 15 towards the room floor 25 is emitted. In this case, the infrared heating device 1 is detachably plugged into a frame 30 which is fastened to a room wall 26 and is provided with at least one upper cover 31 and one lower cover 32 .

5 illustrates another operating method of an infrared heating device 1 using a diagram, the activation or energizing of the infrared surface radiators 5 being shown schematically over time. The method has the following steps: a) Clocked activation of the plurality of infrared surface radiators 5 over a start-up period (H1) from a predefinable point in time B (start); b) deactivating the plurality of infrared surface radiators 5 over a first pause period (P1); c) Carrying out a phase change heating, comprising heating phases (Hp) with clocked activation of the plurality of infrared surface radiators 5 and pause phases (Pp) with deactivated plurality of infrared surface radiators 5, with all heating phases (each) being shorter in time than the start-up period (H1). and all pause phases (Pp) (respectively) are shorter in time than the first pause period (P1).

The method ends at time E (end) when a predefinable comfort temperature in the area surrounding 22 of the infrared heating device 1 is reached. Step a) can be initiated again at a specified time of day. Furthermore, step a) can be carried out again (automatic restart) if a temperature in the area 22 of the infrared heating device 1 can be determined which is below a specifiable comfort temperature.

In this way it is possible to at least partially alleviate the problems described with reference to the prior art. In particular, a compact infrared heating device was specified, which can heat a room particularly efficiently and also meets high standards with regard to manufacturing costs and operational reliability. Furthermore, an operating method for an infrared heater was specified, which results in improved heating behavior. Reference character list

1 infrared heater

2 housing

3 opening

4 radiation grilles

5 infrared surface heaters

6 surface

7 cavity

8 thermal insulation

9 bezel

10 thermal insulation layer

11 control unit

12 bimetallic switches

13 strut

14 reflector surface

15 infrared radiation

16 angles

17 aluminum sheet body

18 contact surface

19 connection

20 chamber

21 chamber wall

22 environment

23 space heating

24 distance

25 room floor

26 room wall

27 temperature sensor

28 adjuster

29 room

30 frames 31 top cover

32 bottom cover

Claims

Expectations

1 . Infrared heater (1), at least having a housing (2) with a front opening (3), which is made of plastic comprising polyphenylene sulfide (PPS) with a mineral additive, a radiation grille (4), which is made of aluminum and attached to the housing ( 2) can be fastened so that the frontal opening (3) can be covered, a plurality of infrared surface radiators (5) which are formed with a ceramic cavity construction, the infrared surface radiators (5) pointing towards the radiation grid (4 ) are designed with a surface (6), the cavity (7) of the infrared panel radiator (5) is filled with thermal insulation (8) and the area output of an infrared panel radiator (5) is 20 to 35 kW/m ² , one Enclosure (9) made of light-reflecting material, in which the plurality of infrared panel radiators (5) can be accommodated, a thermal insulation layer (10) which can be attached at least partially between the housing (2) and the enclosure (9), a Control unit (11) for clocked operation of the plurality of infrared surface radiators (5), clocking being carried out with an associated bimetallic switch (12) which has a switching temperature above 125°C.

2. Infrared heater (1) according to claim 1, wherein the plurality of infrared panel radiators (5) are not parallel or at least partially inclined to each other in the frame (9) can be mounted.

3. Infrared heater (1) according to one of the preceding claims, wherein the radiation grid (4) is designed with struts (13) which realize an openness of at least 50% with regard to the frontal opening (3) and wherein reflector surfaces (14) are formed , with which the Infrared radiation (15) of the infrared surface radiator (5) when leaving the housing (2) is deflected at an angle (16). An infrared heater (1) as claimed in any preceding claim, wherein there is a single enclosure (9) formed with an aluminum sheet body (17). Infrared heater (1) according to one of the preceding claims, wherein a single thermal insulation layer (10) is provided which covers at least 85% of a contact surface (18) of the frame (9) and housing (2). Infrared heater (1) according to any one of the preceding claims, wherein electrical or electronic connections (19) of components in the housing (2) at least partially passed through the frame (9), the thermal insulation layer (10) and the housing (2) and in a rear chamber (20) with a chamber wall (21) open out, wherein in the chamber (20) the control unit (11) is at least partially arranged. Method for operating an infrared heating device (1) according to one of the preceding claims, at least comprising the following steps: d) clocked activation of the plurality of infrared surface radiators (5) over a start-up period (H1); e) deactivating the plurality of infrared panel radiators (5) over a first pause period (P1); f) Carrying out a phase change heating, comprising heating phases (Hp) with clocked activation of the plurality of infrared surface radiators (5) and pause phases (Pp) with deactivated plurality of infrared surface radiators (5), with at least one heating phase being shorter in time than the start-up period (H1 ) is. Method according to Claim 7, in which, in step c), a pause phase (Pp) is also shorter in time than the first pause period (P1). Method according to one of Claims 7 or 8, in which step a) is carried out if a temperature in the surroundings (22) of the infrared heating device (1) can be determined which is below a predeterminable comfort temperature. Method according to one of Claims 7 to 9, in which the method is ended when a predeterminable comfort temperature in the area (22) surrounding the infrared heating device (1) has been reached. Space heater (23), comprising at least one infrared heater (1) according to one of the preceding claims, which is fixed at a predeterminable distance (24) to the room floor (25) on or in a room wall (26), being remote from the at least one infrared heater ( 1) a temperature sensor (27) for the room temperature and an adjustment element (28) for a comfort temperature are installed in the room (29), which are connected to the control unit (11) of the infrared heater (1) in a data-conducting manner. Space heater (23) according to claim 11, wherein at least one infrared heater (1) is attached to the room wall (26) or the radiation grille (4) is designed in such a way that a significant proportion of the infrared radiation (15) leaving the infrared heater (1) is directed towards the Room floor (25) emits. Space heater (23) according to claim 11 or 12, wherein at least one infrared heater (1) is releasably plugged into a frame (30) fixed to at least one room wall (26) and having at least a top cover (31) and a bottom cover (32) is provided. Computer program set up to carry out a method according to one of Claims 7 to 10.

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