DE29802563U1 - Stove for solid, free-flowing fuels, especially for wood pellets - Google Patents

Description

G 9406 EN

Wodtke GmbH

Rittweg 55 - 57

72070 Tuebingen

Stove for solid, free-flowing fuels, especially for wood pellets

The invention relates to a furnace for solid, free-flowing fuels, in particular for wood pellets, with a combustion chamber, an automatic fuel feed device and intake openings for room air arranged in the lower area of the furnace and outlet openings for the room air arranged in the upper area of the furnace.

In order for the room air to flow through such a stove, which is generally known as a pellet stove, to be heated and for the fuel container (which is preferably integrated) and the fuel supply to not heat up too much, convection must be generated in the stove. In the stoves of this type known to date, a fan causes the convection. However, this fan increases the need for electrical energy, causes noise, costs money and can create an unpleasant draft in the room in which it is installed. The fan also requires additional control and, if it fails, can lead to the stove and the fuel in the fuel container overheating.

G 9406 EN - 2 -

The invention is based on the object of improving such a furnace for solid, free-flowing fuels in such a way that the necessary convection is generated without a fan and the disadvantages mentioned above are avoided.

The stated object is achieved according to the invention in that at least one room air-heating gas heat exchanger is provided, which has at least one heat conducting plate that leads the heated room air to the outlet openings of the oven. This constructively simple and inexpensive solution brings about the required convection. The at least one heat conducting plate results in a smaller cross-section of the flow channel for the room air, which increases the chimney effect. In addition, a comfortable room atmosphere is created, since annoying fan noise and unpleasant drafts are eliminated. The at least one room air-heating gas heat exchanger can have a ribbed surface. The resulting increase in surface area enables the heat from the combustion chamber to be better transferred to the room air to be heated and the efficiency of the oven can be improved. For optimal heat yield, the oven can have room air-heating gas heat exchangers in the upper area and/or on the side walls and/or the rear wall of the combustion chamber. To optimize the chimney effect of the room air-heating gas heat exchanger, the stove can have a relatively large construction height. This can automatically require a larger storage container, which at the same time increases the ease of use, as fuel does not have to be refilled as often. A slope, which can be provided at the upper end of the combustion chamber, increases the exchange surface required to transfer the heat, thus automatically improving free convection.

An embodiment of a furnace according to the invention is explained in more detail below with reference to the accompanying drawing.

G 9406 EN - 3 -

In detail:

Fig. 1 is a sectional side view of the furnace;

Fig. 2 a sectional view along the line II - II

through the furnace of Fig. 1;

Fig. 3 is a sectional side view of a second

Construction variant of the oven.

Fig. 1 shows a furnace 10 with a combustion chamber 11, an air inlet 12, an air outlet 13 and heat conducting plates 14. The room air is sucked into the furnace at the air inlet 12 and then flows upwards past the combustion chamber 11. As it flows around the combustion chamber 11, the air heats up, flows over the heat conducting plates 14 and then leaves the furnace 10 at the air outlet 13. The flow channels created by the heat conducting plates 14 cause a chimney effect that increases the flow speed. The combustion chamber 11 ends at its upper end with a slope 15. In comparison to a horizontal end of the combustion chamber, the sloped upper part increases the surface of the combustion chamber and thus improves the heat transfer to the air to be heated.

The sectional view in Fig. 2 shows two side room air-heating gas heat exchangers 16. After leaving the combustion chamber 11, the flue gas enters the room air-heating gas heat exchangers 16 via an opening not shown here. Behind the combustion chamber 11 there is a storage container 17 for holding the solid fuel. The heat conducting plates 14 can be seen between the storage container 17 and the combustion chamber 11.

Fig. 3 shows a variant of a furnace 20 with a greater height. In this variant, the heat conducting plates 21 are directed towards the lower end of the combustion chamber 22 in the direction of a direction not described in detail here.

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G 9406 EN

shown air inlet opening on the back of the oven 20. The upwardly tapering cross-section of the air channels formed by the heat conducting plates 21 increases the flow speed of the room air to be heated, which means that the chimney effect of free convection is even better.

Claims (5)

G 9406 DE - 5 - Protection claims: 1. Oven (10, 20) for solid, free-flowing fuels, in particular for wood pellets, with a combustion chamber (11), an automatic fuel feed device and intake openings (12) for room air arranged in the lower area and outlet openings (13) for the room air arranged in the upper oven area, characterized in that at least one room air-heating gas heat exchanger (16) is provided, which has at least one heat conducting plate (14) which guides the heated room air to the outlet openings (13) of the oven (10, 20). 2. Oven according to claim 1, characterized in that the at least one heat exchanger (16) has a ribbed surface. 3. Oven according to one of claims 1 or 2, characterized in that the room air-heating gas heat exchanger (16) is arranged in the upper region and/or on the side walls and/or the rear wall of the combustion chamber (11). 4. Oven according to one of claims 1 to 3, characterized in that the combustion chamber (11) has a relatively large overall height. 5. Oven according to one of claims 1 to 4, characterized in that the combustion chamber (11) is bevelled at the upper end.