CN116412544A

CN116412544A - Heater

Info

Publication number: CN116412544A
Application number: CN202310018771.2A
Authority: CN
Inventors: A·舍费尔; P·格拉泽; B·巴斯纳
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2022-01-10
Filing date: 2023-01-06
Publication date: 2023-07-11
Also published as: DE102022200144A1

Abstract

The invention relates to a heater (10) having a combustion chamber (12), an inlet air path (14) for inlet air (16), an exhaust gas path (18) for exhaust gas (20), an exhaust gas collector (22), a blower (24) arranged between the inlet air path (14) and the exhaust gas path (18), a sensor (26) arranged in the exhaust gas path (18) and/or the inlet air path (14), a switch (28), and a line (30) between the sensor (26) and the switch (28). According to the invention, the line (30) can be heated indirectly.

Description

Heater

Technical Field

The invention relates to a heater having a combustion chamber, an intake air path for intake air, an exhaust gas path for exhaust gas, an exhaust gas collector and a blower arranged between the intake air path and the exhaust gas path.

Background

Such a heater is known from CN 209436995 U1.

Disclosure of Invention

The heater according to the invention has a combustion chamber, an inlet air path for inlet air, an exhaust gas path for exhaust gas, an exhaust gas collector and a blower arranged between the inlet air path and the exhaust gas path, a sensor arranged in the exhaust gas path and/or the inlet air path, a switch and a circuit between the sensor and the switch, characterized in that the circuit can be heated indirectly. This has the following advantages: the route can be freely selected in a wide range. This route does not necessarily have to be routed through the combustion chamber wall or the wall of the exhaust gas collector, whereby an elaborate sealing at such a location is avoided.

In particular, in heating devices with an atmospheric burner, which can be operated without connection to a chimney, blowers are used to safely conduct the exhaust gases to the outside. The blower must be reliably implemented against wind pressure with a certain minimum conveying quantity. For this purpose, a probe (for example a Prandtl probe Prandtl-Sonde) can be arranged in the exhaust gas path (also referred to as exhaust gas channel), which probe supplies an overpressure to the pressure switch on the pressure side and a negative pressure on the outflow side by means of a thin hose or a small tube. The formation of condensation water in the line, i.e. in the hose or the small tube, is now avoided by the invention. However, it is not necessary to conduct the line through the exhaust collector.

Advantageous embodiments of the heater according to the invention are given below. A low cost embodiment is obtained when the line can be heated by the heat generated in the combustion chamber.

In a simple manner, the line can be led outside the combustion chamber along the wall of the combustion chamber and/or the exhaust gas collector.

Furthermore, a partition can be provided in the combustion chamber and/or the exhaust gas collector, which partition shields the line from the exhaust gas of the combustion chamber or the exhaust gas collector.

If the line is provided with heat transfer means, heat can be led to the line from another point.

In terms of design, it is very simple to implement that a heat transfer element or the heat transfer element protrudes into the combustion chamber and/or the exhaust gas collector and transfers heat to the circuit.

The effect is increased if the line is at least partly provided with insulation.

In a preferred embodiment, the line has one or more tubes.

The switch may simply be mounted on the outside of the combustion or exhaust chamber.

In a further advantageous embodiment, the heating circuit can be heated by means of a separate heating device. Here, indirect heating is also achieved for the main heat source in the combustion chamber.

Drawings

One embodiment of a heater according to the present invention is shown in the drawings and described in more detail in the following description. Here, it is shown that:

figure 1 shows a schematic view of a heater,

fig. 2 to 4 each show a sectional view according to A-A in fig. 1 in an alternative variant.

Detailed Description

In fig. 1, a heater 10 is shown having a combustion chamber 12, an inlet air path 14 for inlet air 16, an exhaust gas path 18 for exhaust gas 20, an exhaust gas collector 22 and a blower 24 arranged between the inlet air path 14 and the exhaust gas path 18, a sensor 26 arranged in the exhaust gas path 18 and/or in the inlet air path 14, a switch 28 and a line 30 between the sensor 26 and the switch 28.

As can be seen, the feed air path 14 in the exemplary embodiment is not closed, but is guided through the heater 10 in an outer housing 31. The housing 31 has one or more openings 32 through which the inlet air 16 can flow. From there, the feed air 16 flows to the burner 34.

In an embodiment, the burner 34 is flowed through from bottom to top. Fuel is supplied to the burner 34 through a fuel line 36. Along with the feed air 16, fuel enters the combustion chamber 12 in a combustor 34 for combustion. In an embodiment, the burner 34 is designed as an atmospheric burner 34.

The combusted charge air/fuel mixture, hereinafter referred to as exhaust gas 20, flows through the combustion chamber 12 and transfers heat to the medium to be heated in a heat exchanger 38. The medium is supplied via a line, not shown here, to a heating circuit, also not shown.

An exhaust gas collector 22 is connected downstream of the heat exchanger 38 in the flow direction, in which the exhaust gas 20 is collected and fed to the exhaust gas path 18. The exhaust gas path 18 then leads to the outside of the building in which the heater 10 is installed.

The blower 24 assists combustion and ensures that the exhaust gas 20 is reliably led out even under adverse external conditions. A sensor 26 is provided in the exhaust path 18, which detects the flow in the exhaust path 18. For example, a Prandtl-Sonde probe (Prandtl-Sonde) may be used as the sensor 26.

The sensor 26 is connected to a switch 28 by a line 30. Switch 28 shuts off burner 34 when there is insufficient flow. In an embodiment, the switch 28 is connected to a controller 40 that may consider other parameters for controlling the blower 24 and/or the burner. This may be, for example, the current heat demand, the indoor temperature and/or the outdoor temperature, etc. Depending on the sensor and the switch type, variable switching stages can also be implemented. To shut down the burner 34, the switch 28 is connected directly or via a controller 40 to a valve, not shown, which monitors the fuel supply line 36.

The line 30 leads out of the exhaust gas path 18 and extends at least in regions in the region of influence of the supply air. Depending on the temperature of the feed air, this may lead to condensation in the line, especially if the feed air is cooled, which makes reliable switching difficult.

It is therefore an object of the present invention to avoid condensation of liquid in the line 30 even under adverse temperature conditions. According to the invention, this is achieved by being able to indirectly heat the line 30. I.e. to supply heat to the line 30. The circuit is not directly exposed to the hot exhaust gases 20.

If the line 30 is arranged, for example, directly in the combustion chamber 12 or in the exhaust gas collector 22, direct heating is obtained. For this purpose, however, the line 30 must penetrate at least one wall 42 of the combustion chamber 12 or of the exhaust gas collector 22, which would be associated with a corresponding sealing effort.

In the simplest case, the line 30 may extend along the outside of the exhaust gas collector 22, as shown in fig. 1, and thus indirectly absorb heat through the wall of the exhaust gas collector 22. The line 30 may also extend along the outer wall of the combustion chamber 12. In both cases, the line 30 is heated indirectly by the heat generated in the combustion chamber 12.

In a further embodiment according to fig. 2, the combustion chamber 12 and/or the exhaust gas collector 22 has a recess in which the line 30 can extend. A spacer 43, for example in the form of a shielding plate, is then provided.

In another embodiment according to fig. 3, the line 30 is provided with a heat transfer device 44. In an exemplary embodiment, the heat transfer element 44 has the shape of a sheet 46, which on the one hand rests on the line and on the other hand protrudes into the exhaust gas collector 22 or the combustion chamber 12. No elaborate seals are required for this purpose. The sheet material may extend through the wall 42 and simply be welded to the wall 42, which facilitates heat transfer to the heat transfer device 44 and thus to the circuit 30.

In an embodiment, at least the circuitry 30 is surrounded at least in areas by thermal insulation 48. This can prevent cooling too quickly when the heater 10 is turned off. Thus, condensation of the liquid in line 30 is at least delayed. Together with the indirect heatable nature of the line 30, an effective prevention of condensation can be achieved.

The line 30 is provided for transmitting the value determined by the sensor 26 for the activity of the blower 24 to the switch 28. In one embodiment, the line 30 may be provided as a tube 50, which provides pressure as a value to the switch 26, for example. However, two or more tubes 50 may also be provided, which provide the pressure differential to the switch 28 as determined by the sensor. The pressure differential may consist of a static pressure and a dynamic pressure. Depending on the sensor type, different values can therefore be determined. Thus, the switch 28 must be coordinated with the sensor type.

Instead of one or more tubes 50, one or more hoses may also be used.

The switch 28 may be disposed at any location in the heater 10 or may be disposed outside the heater. As shown in fig. 2, the switch 28 may also be arranged outside the combustion chamber 12 or the exhaust gas collector 22. In this way, the switch 28 is also indirectly heated. The switch 26 may also be surrounded by insulation 48.

In the event that cooling of the line 30 and thus condensation cannot be completely avoided, for example if the heater 10 has a long standstill phase and/or the feed air 16 has an extremely low temperature, a separate heating device 52 may alternatively or additionally be provided. The heating means then extends along a line or, for example, between two tubes 50 if such tubes are provided.

Claims

1. A heater (10) having a combustion chamber (12), an inlet air path (14) for inlet air (16), an exhaust gas path (18) for exhaust gas (20), an exhaust gas collector (22), a blower (24) arranged between the inlet air path (14) and the exhaust gas path (18), a sensor (26) arranged in the exhaust gas path (18) and/or the inlet air path (14), a switch (28) and a line (30) between the sensor (26) and the switch (28), characterized in that the line (30) is indirectly heatable.

2. The heater (10) of claim 1, wherein the circuit (30) is heatable by heat generated in the combustion chamber (12).

3. The heater (10) according to any of the preceding claims, wherein the line (30) is directed outside the combustion chamber (12) along a wall (42) of the combustion chamber (12) and/or the exhaust gas collector (22).

4. The heater (10) according to any of the preceding claims, characterized in that a partition (43) is provided in the combustion chamber (12) and/or the exhaust gas collector (22), which partition shields the line (30) from the exhaust gas (20) of the combustion chamber (12) or the exhaust gas collector (22).

5. The heater (10) of any preceding claim, wherein the circuit (30) is provided with heat transfer means (44).

6. The heater (10) according to any of the preceding claims, characterized in that a heat transfer means or the heat transfer means (44) protrudes into the combustion chamber (12) and/or the exhaust gas collector (22) and transfers heat to the line (30).

7. The heater (10) of any of the preceding claims, wherein the circuit (30) has, at least in part, insulation (48).

8. The heater (10) of any of the preceding claims, wherein the circuit (30) has a tube or a plurality of tubes (50).

9. The heater (10) of any of the preceding claims, wherein the switch (28) is mounted on the outside of the combustion chamber (12) or exhaust chamber (22).

10. The heater (10) according to any of the preceding claims, wherein the line (30) is heatable by means of a separate heating device (52).