EP0496043B1 - Heating stove for solid fuels - Google Patents

Description

The invention relates to a heating stove operated with solid fuels such as wood, in particular a stove, according to the preamble of patent claim 1.

In a known heating furnace of this type (EP-A-0 297 086), a downwardly movable floor acts via an extension on one arm of a balance beam, over the other arm thereof, and an extension, a rotatably mounted rod and a further extension to pivot an air supply duct-associated flap into its closed position if the fuel weight falls below a certain value. The flap can only occupy two positions in this heating furnace, namely in addition to the closed position mentioned, an open position in which the channel is fully open. The flap is moved to the open position by opening the combustion chamber door using a lever system.

The known heating furnace has the disadvantage that continuous regulation of the passage cross section of the air supply channel as a function of the fuel weight is not possible. The air supply duct is completely open during the entire combustion process and is only completely closed at the end of the combustion process when the remaining fuel falls below a certain minimum weight. The air supply in this heater is therefore always at a maximum, so that on the one hand the combustion takes place very quickly and on the other hand optimal and environmentally friendly combustion is not possible, especially even in low-load operation. A Another disadvantage of the known heating furnace is that the mechanism for controlling the passage opening of the air supply duct is mechanically complex, requires maintenance and requires a considerable amount of space. Finally, this known heating furnace has the disadvantage that the combustion residues remain on the floor and therefore influence the control of the air flap. The control is thus dependent on the amount of residue that varies depending on the fuel, so that depending on the setting there is a risk that the furnace will not close at all or too soon. In the first case, the furnace cools down, while in the second case there is a risk of flue gas explosions.

There is also already known a heating oven with an automatic fume cupboard control (DE-PS 102406), in which a slide in the fume channel is moved by a grate that can be pivoted downwards via a lever mechanism and a weighing device. Because of the mechanical complexity and the high space requirement, this heating furnace has the disadvantage that when the grate is pivoted downwards, part of the fuel can slip into the ash-receiving space. This not only leads to an unnecessarily high fuel requirement, but also entails the risk that when the grate is lifted, unburned fuel parts are trapped between the grate and the furnace wall as the fuel weight decreases, causing the grate to be raised completely and thus the slide in the flue duct to be completely closed prevent.

The invention has for its object to develop a heating furnace of the type mentioned in such a way that continuous and safe control of the air supply is possible, the mechanism taking up as little space as possible and should be mechanically inexpensive.

The features are to solve this task of claim 1 provided.

Because of this design, the closure arrangement or the closure arrangements move synchronously with the floor containing the grate, which enables a continuous regulation of the air supply through the air supply opening or air supply openings and thereby optimizes the combustion during the entire combustion process. At the beginning of the burning process, i.e. when the grate is completely loaded with fuel, the air supply opening is fully open, so that a maximum amount of air is supplied, while after the firing process the air supply opening is completely closed, so that the heating furnace cannot cool down due to drafts. With this configuration, a space-consuming and mechanically complex weighing device can also be dispensed with.

Advantageous developments of the invention are characterized by the subclaims.

According to a preferred embodiment, the dependence of the throttling of the air supply on the burnup is non-linear.

It is particularly advantageous if the closure arrangement closes completely after a certain amount of erosion, because this ensures optimal control of the air supply.

However, in this case it is expedient if, according to claim 4, additional permanently open air supplies are provided, which is expediently provided according to claim 5 above the floor, for example on the upper edge of the combustion chamber door or in the rear wall of the combustion chamber.

Manually controllable additional air supply openings are also to be provided, for example in order to be able to provide a constant amount of additional air during heating or with certain fuels.

A structurally particularly simple and very reliable practical embodiment is characterized by claim 7.

Advantageous developments of this practical embodiment are characterized by claims 8 to 12.

Fig. 1

eine teilweise geschnittene Seitenansicht eines erfindungsgemäßen Kaminofens und

Fig. 2

eine rein schematische und stark verkleinerte Schnittansicht nach Linie II-II in Fig. 1 bei herausgenommenem Boden mit den daran befestigten Bauelementen.

The invention is described below, for example with reference to the drawing; in this shows:

Fig. 1

a partially sectioned side view of a stove according to the invention and

Fig. 2

a purely schematic and greatly reduced sectional view along line II-II in Fig. 1 with the floor removed with the components attached to it.

According to FIGS. 1 and 2, an oven housing 23 made of chrome-nickel steel sheet has an essentially trapezoidal horizontal cross section and is provided with a rectangular front opening 33 in the upper region. The housing 23 is laterally and rearally insulated by rock wool mats 35, which are only shown in FIG. 1.

The furnace housing 23 encloses a combustion chamber 13 which opens at the top into a smoke vent opening 11, to which a hood 12 connects, which has a connection piece 36 for a furnace tube at the top, rear or side.

The front opening 33 is closed by a combustion chamber door 37 which can be pivoted about a hinge 38 with a vertical axis in order to either close the front opening 33 or open it for filling fuel 21. The front surface of the combustion chamber door 37 is designed as a fire-resistant glass pane 39.

In the upper frame leg 40 of the combustion chamber door 37 there are air inlet slots 41 immediately behind the upper edge of the glass pane 39. Between the upper area of the glass pane 39 and a holding bracket 42 arranged at a distance behind it there is an air settling agent 43 which has an increased flow resistance and which serves to to calm the outside air flowing in in the direction of the arrow and to have it flow as a laminar flow in the direction of the dashed line at the rear of the glass pane 39.

This air is also used to maintain the combustion.

Provided in the rear wall 44 of the furnace housing 23 in the lower half of the height of the combustion chamber 13 is an air supply duct 14 running perpendicular to the plane of FIG. 1, which on its side facing the combustion chamber 13 by an air sedative e.g. is closed by a wire mesh 70 and serves to evenly distribute air into the combustion chamber 13 from the outside.

Below the front opening 33 is the floor 17 of the combustion chamber 13, which adjoins the front wall 46 of the furnace housing 23 via a ramp 45 which rises obliquely to the lower edge of the front opening.

Around its central area, the base 17 has a square or round opening 47 which is closed by a removable or fold-out grate 18 which rests on holding projections 48 of the base 17.
In all four corners of the trapezoidal cross-section, the frame parts 49 provided by the ramp 45, laterally and rearward, and the grate 18 lie on support rods 50, which are shown in plan view in FIG. 2 and of which only the rear left rod 50 is shown in FIG. 1.

The vertical bars 50 are e.g. through holes 52 in the upper stop plate 25 and 53 in the lower stop plate 51. In the embodiment variant shown in FIG. 1, the rods 50 act on a coil or disc spring via a cross pin 54. In other designs, not shown, the rods 50 act via their lower end, e.g. on leaf springs or on a lever system loaded by counterweights. The aforementioned spring, weight or other forces allow a lowering of the base 17 corresponding to the fuel weight with the intermediate piece 57 and the closure flap 20. Not all possible variants are to be explained in detail here; Therefore, only the solution shown in FIG. 1, in which the support rods 50 act on helical compression springs 24, is described in detail below.

Between the lower horizontal support plate 51 and a transverse pin 54 provided below the upper stop plate 25 within the rod 50 extends a prestressed helical compression spring 24, which moves the associated rod 50 into an upper end position in which the transverse pin 54, which is on both sides of the Rod 50 protrudes from the bottom against the stop plate 25.

The upper end faces 55 of the four support rods 50, which are arranged clearly above the stop plate 25, together form a flat support surface for the bottom 17, which is arranged vertically displaceably in the furnace housing 23.

At the bottom of the bottom 17, around the opening 47 for the grate 18, a cylindrical sheet metal jacket 28 is tightly attached, which in its lower area is arranged in a tightly arranged one there Hose 29 of corresponding diameter merges, which in turn is placed tightly around a cylindrical flange 56, which also has a corresponding diameter.

From the lower end of the cylindrical sheet metal jacket 28, a transverse rail 58 extends over two diametrically opposed intermediate members 57 parallel to a base plate 27, which has a diameter corresponding to the cylindrical flange 56 and centrally has an air supply opening 15 and eccentrically an additional air supply opening 16.

The base plate lies on an elastic sealing ring 59 on a horizontal support plate 34, which is also shown in FIG. 2 and runs around a central rectangular opening 60 at the bottom of the furnace housing 23.

On the cross rail 58, a horizontal circular closure flap 20 is fastened centrally via a bolt 61 with two nuts 62 locked against one another, which in the position shown, i.e. when the cross pins 54 abut against the stop plates 25 from below, the air supply opening 15 closes.

The additional air supply opening 16 is closed from below by a flap 31 or a slide which can be pivoted about a horizontal axis 63 and which can be actuated by the operator via a linkage 32 by means of a handle 64 from the front opening 33.

Arranged within the cylindrical sheet metal jacket 28 is an ash box 26 which is concentric with it and whose diameter is slightly smaller than that of the circular opening 47 for the arrangement of the grate 18. In this way it is ensured that the ash pan 26 on the one hand with the grate 18 removed or folded up through the opening 47 can be removed at the top or set through this opening 47 and the ash falling through the grate 18 can fall into the ash receiving space 19 of the ash box 26.

The closed bottom 65 of the ash box 26 extends above the cross member 58, while its side walls at 66 still extend to the bottom plate 27 on which they rest, so as to support the ash box 26 on the bottom plate 27. In the area of the cross member 58, the areas 66 of the side walls of the ash pan 26 which extend below the floor 65 have corresponding cutouts which must also ensure the freedom of movement of the cross member 58 described below.

The grate opening 47, the ash pan 26 and the circular cylindrical sealing plate 28 have a common vertical central axis 30.

Underneath the support rods 50 there is a clear play 67 of e.g. 5 to 10 mm, by which the movement play of the floor 17 described in the following is ensured.

The stove works as follows:

If the fuel 21 indicated in dashed lines in FIG. 1 is placed, for example in the form of pieces of wood, on the bottom 17 and in particular the grate 18, the prestressing force of the correspondingly designed suspension springs 24 at the four corners of the furnace housing 23 is overcome and the bottom 17 presses it Support rods 50 together with further compression of the suspension springs 24 until the game 67 between the lower end of the rods 50 and the support plate 34 is overcome. Here, the flap 20 lifts from the lower edge of the air supply opening 15, so that there is an annular gap through which, according to the two dashed arrow lines in FIG. 1, outside air can enter the space delimited by the circular cylindrical plate 28, the hose 29 and the base plate 27. The air passes through the cutouts described above in the bottom parts 66 of the walls of the ash pan 26 according to the dashed arrow lines in the space 68 between the ash pan 26 and the circular cylindrical plate 28 up to the grate 18, where the air is then dashed for the combustion of the indicated fuel 21 is available.

The linkage 32 can be moved downward by hand via the handle 64, whereby the flap 31 opens downward by pivoting about the axis 63 or a slide and releases the additional air supply opening 16, whereby further air enters the interior of the sealing plate 28 and for example, can be available for heating.

With increasing combustion, the grate 18 is relieved and ash also falls through the bars of the grate 18 in the direction of the dash-dotted arrow lines down into the ash box 26, whereby the bottom 17 is increasingly relieved until finally the force of the springs 24, counterweights or other components is sufficient to raise the bottom 17. When the amount of fuel 21 falls below a certain amount, the bottom 17 finally assumes the uppermost position shown in FIG. 1, in which the air supply opening 15 in the bottom plate 27 is completely closed. When the fuel 21 is burned, the throttling of the air supply at the air supply opening 15 increases steadily, so that the amount of air available for combustion is optimized at every moment.

When the air supply openings 15, 16 are completely closed, due to the hermetic sealing of the space below the grate 18, no air can reach the grate 18 from below. For complete combustion, however, the air entering through the air duct 14 and the air supply slot 22 below the air inlet slots at the upper edge of the combustion chamber door 37 and through the duct 14 is still available.

The spatial compactness of the automatic air control arrangement according to FIG. 1 is particularly noteworthy. Due to the concentric arrangement of the sealing plate 28 and ash box 26, practically the entire space below the grate 18 is made available for the ash reception without the air supply control being impaired.

It is also particularly advantageous that the entire arrangement can easily be lifted up from the support rods 50 out of the base 17 and the parts attached to it up to the base plate 27 and can be removed or inserted through the front opening 33 with the door 37 open.

As a result, the lower part of the interior of the furnace housing 23 (FIG. 2) is fully accessible and can be cleaned, for example with the aid of a vacuum cleaner, of ash or other impurities located on the support plate 34. In this way, any repair work on the base receiving part of the furnace can be carried out without any assembly and disassembly.

Below the support surface 34, the furnace housing preferably has height-adjustable feet 69.

Claims (14)

1. Heating stove operated with solid fuels such as wood, in particular a chimney stove, with a combustion chamber (13) which has an air supply (14, 15, 16, 22) and which opens into a flue (11) from the side or from the top, with at least one air supply opening (15) which can be controlled to be opened or partially or completely closed via a closing arrangement (20), wherein the closing arrangement (20) is automatically actuated depending on the fuel weight lying on the base (17) such that the closing arrangement (20) is open up to a maximum in the case of unburned fuel (21) and closed in the case of entirely burned fuel (21), and wherein the base (17) in the stove housing (23) is arranged to be displaceable in the downward direction against a force (24) and is mechanically coupled with the closing arrangement(s) (20) which is or are associated with the controlled air supply opening(s) such that the closing arrangement(s) (20) is or are closed in the case of a base (17) which is in the upper abutment position (25) and is or are completely open in the case of a filled-up desired amount of fuel,
   characterised in that
   a grate (18) which can be taken out is arranged in the base of the heating stove;
   in that there is an ash receiving space (19) and at least a part of the air supply (15, 16) under the grate (18);
   and in that the closing arrangement(s) (20) is or are connected to the base (17) via mechanical intermediate members (28, 57, 58, 61, 62) to form a constructional unit, so that the closing arrangement(s) moves or move synchronous with the base, so that exactly the air amount required for an optimum combustion is always supplied to the fuel (21).
2. Heating stove in accordance with claim 1,
   characterised in that
   the dependence of the throttling of the air supply from the burn-off is non-linear, such that the increase of the throttling becomes larger during the course of the burn-off process than it was at the beginning of the same.
3. Heating stove in accordance with claim 1 or 2,
   characterised in that
   the closing arrangement (20) completely closes the associated air supply opening (15) or the associated air supply openings after the falling below a specific fuel weight.
4. Heating stove in accordance with one of the preceding claims,
   characterised in that
   at least one further, continually open air supply opening (14, 22) is provided aside from the air supply opening(s) (15) which can be controlled by the closing arrangement (20).
5. Heating stove in accordance with claim 4,
   characterised in that
   the continually open air supply (14, 22) is above the base (17).
6. Heating stove in accordance with one of the preceding claims,
   characterised in that
   one or more additional air supply openings (16), which are to be manually closed or completely or partially opened, are provided below the base (17).
7. Heating stove in accordance with one of the preceding claims,
   characterised in that
   the base (17) containing the grate (18) is arranged to be displaceable in the downward direction against a spring force, weight, or similar force (24) and is held in an upper abutment position (25) by the aforementioned force (24) until the desired fuel amount is filled on the base (17), following which the base (17) sinks down to its lower position;
   in that the controlled air supply opening (15) or the controlled air supply openings are provided in a base plate (27) which is arranged below the base;
   and in that the base (17) is mechanically coupled with a closing flap (20) or a plurality of closing flaps associated with the controlled air supply opening or the controlled air supply openings such that the closing flap(s) (20) is or are closed in the case of a base (17) which is in the upper abutment position (25) and is or are completely open in the case of a filled-up desired amount of fuel and increasingly moves or move in the closing direction in the case of increasing burn-off until it or they are once again closed after the falling below of a specific fuel weight.
8. Heating stove in accordance with one of the preceding claims,
   characterised in that
   an ash chest (26) which does not support itself at the base (17) is arranged below the grate (18).
9. Heating stove in accordance with claim 7 and 8,
   characterised in that
   the ash chest (26) supports itself immediately on a base plate (27) which is rigidly connected to the stove housing (23) in the lower region of the stove housing (23).
10. Heating stove in accordance with one of the claims 7 to 9,
    characterised in that
    the ash chest (26) is formed as a pot which is arranged under the grate (18), and is surrounded by a cylinder (28) which is secured at the bottom of the base (17) around the grate (18) in an air-tight manner, the cylinder (28) being connected to the base plate (27) in an air-tight manner via an air-tight telescope connection or via a fire-resistant hose (29), such that the vertical displaceability of the base (17) is ensured.
11. Heating stove in accordance with one of the claims 7 to 10,
    characterised in that
    the additional air supply opening (16), which can be actuated through a heating flap or a fuel selection flap (31) or a slider via a mechanism (32) which can be manually actuated, is provided in the base plate (27).
12. Heating stove in accordance with one of the claims 7 to 11,
    characterised in that
    the base (17) together with the grate (18) as well as the base plate (27) and the constructional elements secured thereto is formed to be removable from the stove housing (23) through the front opening (33).
13. Heating stove in accordance with one of the preceding claims,
    characterised in that
    the grate (18) is arranged in the base (17) to be able to be folded upward.
14. Heating stove in accordance with one of the claims 10 to 13,
    characterised in that
    a transverse rail (58) extends parallel to the base plate (27) from the lower end of the cylinder (28) formed as a metal jacket over two diametrically opposite intermediate members (57).

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