Heating device

Abstract

The invention relates to a heating device, comprising a combustion chamber (1) which is delimited by a wall (1.1) and receives a burner (1.2), an optical sensor unit (2), and a protective disc (3) which is assigned to the wall (1.1) and is arranged between the combustion chamber (1) and the sensor unit (2). It is provided according to the invention that a thermal insulation element (4) with a viewing through-channel (4.1), pointing from the protective disc (3) in the direction of the burner (1.2), for the optical sensor unit (2) is arranged in the combustion chamber (1) on the wall (1.1).

Description

[0001] heater

[0002] The invention relates to a heating device according to the preamble of patent claim 1.

[0003] A heating device of the type mentioned above is known from patent document EP 3 872 462 A1. This consists of a combustion chamber defined by a wall and accommodating a burner, an optical sensor unit, and a protective disk associated with the wall and arranged between the combustion chamber and the sensor unit. In this solution, the sensor unit is arranged relative to the combustion chamber in such a way that it can be cooled by a fluid flow. 15

[0004] The invention is based on the object of improving a heater of the type mentioned above. In particular, a heater with a sensor unit that is, on the one hand, sufficiently temperature-protected and, on the other hand, operates reliably at all times of operation is to be created.

[0005] This object is achieved with a heating device of the type mentioned at the outset by the features listed in the characterising part of patent claim 1. 25

[0006] According to the invention, a thermal insulation element is arranged on the wall of the combustion chamber, with a viewing channel for the optical sensor unit pointing from the protective screen toward the burner. 30 In other words, the solution according to the invention is characterized in that the viewing channel in the thermal insulation element, on the one hand, makes it possible to protect the sensor unit from excessive temperatures; on the other hand, the viewing channel enables the protective screen to be sufficiently tempered to prevent condensation.

[0007] Other advantageous developments of the heating device according to the invention emerge from the dependent patent claims.

[0008] 10

[0009] For the sake of completeness , reference is also made to document DE 10 2009 043 289 B3 , which has a thermal insulation element ( arranged opposite the burner ) but no optical sensor unit .

[0010] 15

[0011] The heating device according to the invention, including its advantageous developments according to the dependent patent claims, is explained in more detail below with reference to the drawings of several exemplary embodiments.

[0012] 20

[0013] It shows

[0014] Figure 1 shows a schematic section through a first embodiment of the heating device according to the invention;

[0015] Figure 2 as a partial section and as a second embodiment 25 of the heater with an optical sensor unit comprising a so-called TO-5 housing; and

[0016] Figure 3, also in partial section and as a third exemplary embodiment, shows an alternatively designed optical sensor unit. 30 The heating device illustrated in the figures initially consists, in a known manner, of a combustion chamber 1 defined by a wall 1.1 and accommodating a burner 1.2, an optical sensor unit 2, and a protective screen 3 associated with the wall 1.1 and arranged between the combustion chamber 1 and the sensor unit 2. The optical sensor unit 2 is preferably designed to detect ultraviolet light. The above term "associated" means that the protective screen 3 is arranged at a maximum distance of 25 mm, preferably a maximum of 10 mm, particularly preferably 5 mm, from the combustion chamber-side surface 10 of the wall 1.1.

[0017] With regard to the aforementioned burner 1.2, it is preferably provided that it is designed for the combustion of a gaseous fuel. In this context, it is further preferably provided that the fuel contains at least 10%, preferably at least 50%, particularly preferably at least 90% hydrogen.

[0018] Furthermore, it is preferably provided in a manner known per se that the combustion chamber 1 has a cover accommodating the burner 1.2, the aforementioned wall 1.1 being formed as part of this cover.

[0019] Furthermore, as can be seen from the figures, it is provided for cooling the optical sensor unit 2 that a part of the sensor unit 2 facing away from the combustion chamber is designed to project into a flow region for a fluid, preferably air.

[0020] 30 It is essential for the heating device according to the invention that a thermal insulation element 4 with a viewing passage 4.1 for the optical sensor unit 2, pointing from the protective screen 3 in the direction of the burner 1.2, is arranged on the wall 1.1 of the combustion chamber 1. To ensure proper detection, it is particularly preferred that an imaginary main axis of the burner 1.2 and an imaginary main axis of the viewing passage 4.1 intersect, preferably inside the burner 1.2. As expressed in other words above, this solution offers, on the one hand, protection of the sensor from overheating and, on the other hand, protection against the formation of condensate that would impede measurement. As a very precautionary measure, it can also preferably be provided that the protective screen 3 is preferably designed to be electrically heatable.Furthermore, it is preferably provided (see Figures 2 and 3) that an optical lens 2.3 for the sensor element is arranged between a sensor element, preferably a UV diode, the optical sensor unit 2, and the protective screen 3. This lens 2.3 bundles the light in a suitable manner (although the bundling effect of the lens can theoretically be close to zero or even equal to zero). Furthermore, this lens 2.3 additionally protects the sensor element (i.e., in addition to the protective screen 3).

[0021] With regard to the aforementioned thermal insulation element 4, it is preferably provided that it is formed from a mineral material, in particular vermiculite (see also https: / / de.wikipedia.org / w / index.php?title=Vermiculit&oldid=226100906). Furthermore, as shown in Figure 1, it is preferably provided that the thermal insulation element 4 is designed to enclose the burner 1.2. For this purpose, it is further preferably provided that the thermal insulation element 4 has a through-opening 4.4 for the burner 1.2. As can be seen in particular from Figure 1, it is further preferably provided that the thermal insulation element 4 is at least approximately disc-shaped and has a flat side 4.2 facing the combustion chamber and a flat side 4.3 facing away from the combustion chamber. In particular, the flat side 4.2 facing the combustion chamber. can, as shown, also be slightly conical, with its recess pointing towards the burner 1.2.- It is particularly preferred that the visible passage channel 4.1 extends from the flat side 4.2 facing the combustion chamber to the flat side 4.3 facing away from the combustion chamber. The aforementioned "disk-shaped" preferably means that the thermal insulation element 4 has approximately the shape of a cylinder whose radius is many times greater than its thickness. 15.

[0022] As can be seen particularly from Figures 2 and 3, it is furthermore preferably provided that the optical sensor unit 2 and the protective screen 3 are designed as a single assembly fastened jointly to the wall 1.1. They are therefore fastened together or jointly to the wall 1.1 during assembly of the heater.

[0023] Looking at it in more detail, to protect against overheating, it is further preferably provided that a sensor of the optical sensor unit 2 is arranged either in a plane of the wall 1.1 or on a side of the wall 1.1 facing away from the combustion chamber. To prevent condensate, it is further preferably provided that the protective disk 3 is arranged at a location in the viewing passage 30 duct 4.1 that is both facing the wall and facing away from the combustion chamber, preferably in the first third of the duct facing the wall. With reference to Figure 2, it is further preferably provided that a T0-5 housing (see also https: / / en.wikipedia.org / w / index.php?title=TO-5&oldid=1069123945) with a measuring opening 2.1 provided on its end face and closed by the protective disk 3 is arranged at the end of the optical sensor unit 2 facing the combustion chamber.

[0024] Furthermore, it is particularly preferably provided that the optical sensor unit 2 has an external thread 2.2 and the wall 1.1 of the combustion chamber 1 has an internal thread 1.3 matching the external thread 2.2.

[0025] As can be seen from the figures, in order to protect the optical sensor 2, it is preferably provided that it is arranged at least predominantly outside the combustion chamber 1. Finally, it is preferably provided that the optical sensor unit 2 is designed to be gas-tight with respect to the combustion chamber 1.

[0026] List of reference symbols

[0027] 1 combustion chamber

[0028] 1.1 Wall

[0029] 1.2 Burner

[0030] 1.3 Internal thread

[0031] 2 Sensor unit

[0032] 2.1 Measuring opening

[0033] 2.2 External thread

[0034] 2.3 optical lens

[0035] 3 protective screen

[0036] 4 Thermal insulation element

[0037] 4.1 Visual passage channel

[0038] 4.2 Flat side facing the combustion chamber

[0039] 4.3 Flat side facing away from the combustion chamber

[0040] 4.4 Passage opening

Claims

Patent claims 1. Heating device, comprising a combustion chamber (1) delimited by a wall (1.1) and accommodating a burner (1.2), an optical sensor unit (2) and an optical sensor unit associated with the wall (1.1) and arranged between the combustion chamber (1) and the sensor unit (2) arranged protective disc (3), characterized in that in the combustion chamber (1) on the wall (1.1) a thermal insulation element (4) with a viewing passage channel (4.1) for the optical sensor unit (2) pointing from the protective disc (3) in the direction of the burner (1.2) is arranged.

2. Heating device according to claim 1, characterized in that the optical sensor unit (2) and the protective screen (3) are designed as an assembly attached together to the wall (1.1).

3. Heating device according to claim 1 or 2, characterized in that a T0-5 housing with a measuring opening (2.1) provided on its front side and closed by the protective disk (3) is arranged at the end of the optical sensor unit (2) facing the combustion chamber.

4. Heating device according to one of claims 1 to 3, characterized in that the optical sensor unit (2) has an external thread (2.2) and the wall (1.1) of the combustion chamber (1) has an internal thread (1.3) matching the external thread (2.2).

5. Heating device according to one of claims 1 to 4, characterized in that the optical sensor unit (2) is arranged at least predominantly outside the combustion chamber (1).

6. Heating device according to one of claims 1 to 5, characterized in that the protective screen (3) is designed to be heatable.

7. Heating device according to one of claims 1 to 6, characterized in that the optical sensor unit (2) is designed to be gas-tight with respect to the combustion chamber (1).

8. Heating device according to one of claims 1 to 7, characterized in that the optical sensor unit (2) is designed to detect ultraviolet light.

9. Heating device according to one of claims 1 to 8, characterized in that the heat insulating element (4) is at least approximately disc-shaped and has a flat side (4.2) facing the combustion chamber and a flat side (4.3) facing away from the combustion chamber.

10. Heating device according to claim 9, characterized in that the viewing passage channel (4.1) is designed to extend from the flat side (4.2) facing the combustion chamber to the flat side (4.3) facing away from the combustion chamber.

11. Heating device according to one of claims 1 to 10, characterized in that a sensor of the optical sensor unit (2) is arranged optionally in a plane of the wall (1.1) or on a side of the wall (1.1) facing away from the combustion chamber.

12. Heating device according to one of claims 1 to 11, characterized in that the protective screen (3) is arranged at a point in the viewing passage (4.1) facing the wall and facing away from the combustion chamber.

13. Heating device according to one of claims 1 to 12, characterized in that an optical lens (2.3) for the sensor element is arranged between a sensor element of the optical sensor unit (2) and the protective screen (3).

14. Heating device according to one of claims 1 to 12, characterized in that a part of the optical sensor unit (2) facing away from the combustion chamber is designed to project into a flow region for a fluid.

Images