FI20237134A1 - Solid fuel fireplace and method in a solid fuel fireplace - Google Patents

Abstract

The invention relates to a solid fuel fireplace (1, 2, 3, 4), which fireplace comprises a hearth (6) with walls (7, 8, 9); a flue gas duct (18) for conducting gases away from the hearth, which flue gas duct is at least partly metallic or made of masonry or made of refractory mass; air ducts for primary and secondary air (11, 12) for conducting air to the fire event of the fireplace at several different points of the fire event; adjustable air intake openings (33), from which the combustion air that the fireplace needs is obtained, and by adjusting the size of which air intake openings (33) the primary and secondary air flows in the air ducts (11, 12) of the fireplace are simultaneously controlled. Behind the air intake openings (33) inside the fireplace there is an air space (40), from which the combustion air required by the fireplace is drawn and from which the primary and secondary air ducts (11, 12) originate. The size of the primary air duct (11) between the air space (40) and the hearth (6) is arranged to be adjustable to control the primary air flow separately from the secondary air flow.

Description

Solid fuel fireplace and method for solid fuel fireplace

TECHNICAL FIELD OF THE INVENTION

The invention relates to a solid fuel fireplace and a method for a solid fuel fireplace as set out in the preambles of the independent claims set out below.

STATE OF THE ART

The aim is to reduce emissions from solid fuel fireplaces, such as heaters, fireplaces, fireplace inserts, stoves, fireplaces or baking ovens. The aim is to improve the durability of fireplaces and their components. At the same time, combustion should be efficient. It is known that precise control of combustion is difficult.

The problems are solved, for example, by modifying the shape of the fireplace and its firebox. For example, a fire guide can be placed in the firebox, which can control the flame, combustion gases and flue gases, protect the firebox structures and enhance the combustion process by increasing the turbulence of the gases and thus their mixing.

Various additional structures are usually susceptible to breakage.

It is known to optimize the amount of combustion air supplied and the supply point.

Sufficient air is needed for a fire to occur. However, too much air can also be detrimental, as the temperature and combustion efficiency can decrease.

WO 2021/165578 A1 discloses a combustion air cassette to be placed in a firebox, comprising — a hollow floor and walls, within which combustion air is conducted. The hollow walls have a number of holes for supplying air from the wall to different heights in the firebox of the fireplace. Primary combustion air is supplied through the floor and secondary air is supplied through the walls.

PURPOSE OF THE INVENTION

— The purpose of the present invention is to reduce or even eliminate the above-mentioned problems encountered in the prior art.

One purpose of the present invention is to provide a solution that reduces emissions from a solid fuel-burning fireplace, such as a stove, fireplace, fireplace insert, storage fireplace, stove, fireplace or baking oven.

One purpose of the present invention is to provide a solution that makes controlling combustion in a solid fuel fireplace easier than ever.

One purpose of the present invention is to provide a solid fuel fireplace that operates more efficiently than before.

One purpose of the present invention is to provide a solid fuel fireplace that is and whose components are more durable.

BRIEF DESCRIPTION OF THE INVENTION

In order to achieve, among other things, the above-mentioned purposes, the solid fuel fireplace and method according to the invention, as well as other objects of the invention, are characterized by what is presented in the accompanying independent patent claims.

The application examples and advantages mentioned in this text apply, as applicable, to the solid fuel fireplace according to the invention, the method, and other objects of the invention, even if they are not always specifically mentioned.

A typical solid fuel fireplace according to the invention comprises — a firebox with walls; — an at least partially metallic or masonry or refractory flue gas duct for conducting gases out of the firebox; — primary and secondary air ducts for conducting air in connection with a fire event in the fireplace at several different points during the fire event, whereby the secondary air duct is arranged to conduct air in connection with a fire event in the fireplace in the general flow direction of the flue gases at least mainly after the primary air;

— adjustable air intakes, from which the combustion air required by the fireplace, i.e. primary and secondary air, is taken, and by adjusting the size of the air intakes, the primary and secondary air flows in the air ducts of the fireplace are simultaneously controlled; whereby — behind the air intakes inside the fireplace there is an air space from which the combustion air required by the fireplace is taken, and from which the primary and secondary air air ducts originate, and — the entire length of the primary air air duct between the air space and the firebox is arranged to be adjustable, in order to control the primary air flow separately from the secondary air flow.

In a typical method according to the invention, a fireplace according to the invention is used in a solid fuel fireplace. The method comprises at least the following steps: — burning solid fuel in a fire chamber of the fireplace, which has walls; — conducting gases out of the fireplace through a flue gas duct made of at least part metal or masonry or refractory mass; — conducting air through primary and secondary air ducts in connection with the fire event of the fireplace at several different points in the fire event, whereby the secondary air duct is arranged to conduct air in connection with the fire event of the fireplace in the general flow direction of the flue gases at least mainly after the primary air, whereby — the combustion air required by the fireplace, i.e. primary and secondary air, is taken in through adjustable air intake openings, — simultaneously controlling the primary and secondary air flows in the air ducts of the fireplace by adjusting the size of the air intake openings; — the combustion air needed by the fireplace is taken from the air space inside the fireplace behind the air intakes, from which the primary and secondary air ducts originate, — the size of the primary air duct between the air space and the firebox is adjusted and thus the primary air flow is controlled separately from the secondary air flow.

The flue gas duct can be made of a material suitable for the purpose, but at least partly of metal and/or masonry material and/or refractory mass. In one embodiment, the flue gas duct is at least partly of metal.

In one embodiment, the flue gas duct is at least partially bricked. In one embodiment, the flue gas duct is at least partially made of a refractory mass suitable for use in a fireplace.

The general direction of flow of flue gases refers to the direction in which the flow of hot gases in the fireplace mainly leads. The gases may swirl in the fireplace, for example in its firebox, even strongly, but ultimately the gases travel out of the fireplace through the flue gas duct.

Flue gas refers to gases produced during the combustion of fuel, such as carbon monoxide, carbon dioxide, various hydrocarbons, and other organic compounds. Flue gas — includes unburned gas. Flue gas refers to gases that are transported away from the firebox and fireplace. Flue gas contains gases produced during the combustion process and may also include unburned flue gas and air.

The solid fuel can be, for example, wood in its various forms. The invention is suitable for — various types of fireplaces, examples include a heater, fireplace, fireplace insert, heat-storing fireplace, stove, fireplace and baking oven.

The invention comprises a new method of controlling the combustion air flows of a solid fuel fireplace. This method of control is also inventive in solid fuel fireplaces other than those mentioned in this application. According to the control method, adjustable air intakes are arranged in the fireplace, from which the combustion air needed by the fireplace, i.e. primary air and secondary air and possibly also tertiary air, is taken. In one application, the adjustable air intakes can be closed completely if desired. In one application, all the combustion air needed by the fireplace is taken through said adjustable air intakes. In one application, the adjustable air intakes are arranged in an openable and tightly closed fireplace door. In one application, said door also functions as a door for the fireplace's firebox, through which fuel is fed into the firebox. In one application, said door functions as an ash door for the fireplace. In one application, the door has a window through which combustion and flame formation in the firebox can be observed.

Behind the air intakes and a possible hatch, there is an air space inside the fireplace, to which combustion air from the air intakes is directed, and from which the combustion air required by the fireplace, possibly all the combustion air required by the fireplace, is taken. In one embodiment, the air space is directly connected to the air intakes. In one embodiment, the air intakes are in one wall of the air space. In one embodiment, the air space is directly connected to the hatch in which the air intakes are located. In one embodiment — said hatch acts as a wall of the air space or part thereof. In one embodiment, the air space is directly connected to the ash box cover. In one embodiment, the ash box cover acts as a wall of the air space or part thereof. In one embodiment, the air space is at least substantially airtight so that during normal use of the fireplace, no air can enter the air space from outside the fireplace other than through the opened air intakes.

The air space is supplied with an air duct for primary air, secondary air and possibly also tertiary air. By adjusting the size of the adjustable air intake openings, the primary and secondary air flows, but also any tertiary air, are simultaneously controlled in the air ducts of the fireplace. The size of the primary air duct between the air space and the firebox can be adjusted, for example by opening and closing the ash box leading from the air space under the grate. In this way, the primary air flow can be controlled separately from the secondary and possibly tertiary air flow. This invention enables a new, more efficient and simple way of controlling the different combustion air flows in the fireplace.

It has now been surprisingly realized that by taking all the combustion air needed by the fireplace, i.e. primary, secondary and possibly tertiary air, into the air space inside the device through the same control device, i.e. adjustable air intake openings, the primary air taken from there can be adjusted separately from the other air, for example by opening and closing the ash door.

For example, in a device according to the invention, in which the primary air duct is controlled by the position of the ash door, the air intakes and the ash door can be kept open during ignition. The amount of air to the air space, i.e. all ducts, e.g. the primary air duct and the fire guide, can then be controlled by adjusting one of the air intakes. When the fire has reached a suitable speed, the ash door, i.e. the primary air duct, can be closed, and yet the amount of secondary and possible tertiary combustion air can be controlled simply by adjusting one of the air intakes.

In one embodiment of the invention, the fireplace comprises a tertiary air duct for conducting air to the fireplace = in connection with a fire event — in the general flow direction of the combustion gases — at least mainly after the primary and secondary air.

In one embodiment of the invention, a fire guide is used in the fireplace and method.

The fire guide is at least partially hollow, and the empty interior of the fire guide can be connected to the air duct of the fireplace to conduct air from the air duct to the interior of the fire guide.

In this method, air is directed from the fireplace's air duct into the interior of the fire damper, thereby cooling the fire damper with the air directed from the air duct.

A fire damper refers to a device placed in the firebox or flue gas duct of a fireplace that controls gas flows. The purpose of a fire damper can be, for example, to direct gases such as combustion gases, flue gases and flames to a larger or smaller area of the firebox or flue gas ducts, to protect parts behind the fire damper, or to increase turbulence. The shape and size of the fire damper are always chosen to suit the situation. For example, it can be plate-shaped, comprising two larger surfaces and possibly an end and/or edges connecting the surfaces. The fire damper can be placed in the firebox in a way that deviates from the direction of its walls, for example under the roof of the firebox to divert gas flows before they hit the ceiling. The fire damper can be located in the flue gas duct after the firebox. For example, in a stove, the fire damper can be placed in the flue gas duct just before the hob to optimally direct hot gases under the hob. There can be one, two, three or more fire dampers in one fireplace, depending on the situation.

The walls of the firebox and the fire guide can be made of a material suitable for the purpose. In one embodiment, the walls of the firebox and/or the fire guide are at least partially made of metal. In one embodiment, the walls of the firebox and/or the fire guide are at least partially made of a refractory mass suitable for use in the firebox. In one embodiment, the walls of the firebox and the fire guide are of the same material.

The fire damper may be retrofittable. One embodiment of the invention is a retrofit kit comprising the fire damper. The retrofit kit may also comprise accessories required for its installation, for example fastening means, fittings and/or tools.

In one embodiment, at least one wall of the firebox is hollow and its interior is connected to an air duct so that the hollow wall functions as an air duct. In one embodiment, the interior of the fire guide is connected to the interior of such a hollow firebox wall. Air then enters the fire guide from the hollow firebox wall. This simplifies the structure.

In one application, the back wall of the firebox, i.e. the wall furthest from the firebox door, is hollow and functions as an air duct. In one application, one or more side walls of the firebox are hollow and function as an air duct. In certain situations, one or two walls acting as air ducts are sufficient.

In one embodiment, the interior of the hollow wall of the firebox is connected to and functions as a part of the secondary air duct. In one embodiment, at least one hollow wall of the firebox has at least one air opening for directing air from the interior of the hollow wall to the firebox as secondary air. In one embodiment, the air openings in the hollow wall are in the upper part of the firebox.

In one application, an air duct, such as a hollow wall of a firebox, acts as an air duct for secondary and tertiary air. Thus, both secondary and tertiary air are supplied through it. In one application, secondary air is supplied to the fire event from the air openings in the hollow wall of the firebox, but part of the air from the hollow wall is led into the fire guide and further as tertiary air out of the air openings in the fire guide.

During combustion, the air in the air duct is typically cooler than the gases flowing in the firebox and thus helps to keep the temperature of the hollow wall and/or fire guide lower. This makes the hollow wall and/or fire guide more durable and protects the fireplace structures behind it more effectively. While the hollow wall and/or fire guide cools from the cool air, the air flowing through it warms up. Warm air can be used for various purposes. For example, if air is taken directly from the outside during the cold season, even very cold air can enter the fireplace from the air duct. Feeding cold air into the firebox could have an adverse effect on combustion.

In one application of the invention, the amount of air introduced into a fire event is controlled.

In one application, the size of the air duct leading to the fire event, i.e. the amount of air flowing through it, is controlled by an air duct closing device. The air duct can be closed even completely if desired. The closing device can be known per se, for example an ash box or hatch that can be opened and closed, or a flap or damper that can be moved or turned by means of a handle or rod, with which the size of the flow channel can be controlled.

The closing device can operate, for example, manually, motorized or automatically.

In one application, a control system is connected to the fireplace or the closing device, which comprises the necessary sensors, such as a temperature sensor, a motor controlling the position of the closing device, and logic, for example a computer software, that controls said motor based on the signals produced by the sensors.

In one embodiment of the invention, the empty interior of the fire damper is surrounded by the walls of the fire damper, at least one of which has at least one air opening for directing air from the interior of the fire damper to the fire chamber and/or the flue gas duct. In this way, the fire damper can be used to bring combustion air to the exact desired point in the fire event. By bringing combustion air to the fire event through the fire damper, the combustion air can be preheated before it is fed into the fire chamber or the flue gas duct. In this way, it is possible to further enhance the efficiency of the fire event.

Preheating the combustion air is important, for example, if the air is taken directly from outside during the cold season. Feeding air into the combustion process through a fire guide also enables a new and efficient way to produce turbulence, i.e. to achieve efficient mixing of gases in the firebox and/or flue gas duct.

In one embodiment, there are several air openings in the hollow walls and/or the fire baffle. The air openings may be, for example, more than 10, more than 20, more than 50, 10-100. The secondary air openings according to the invention may have a diameter of, for example, 3-10 mm, 5-9 mm or 6-8 mm. The tertiary air openings according to the invention may have a diameter of, for example, 1-10 mm, 2-6 mm or 3-4 mm. In one embodiment, the air openings are on one surface of the fire baffle, for example, on the top or bottom surface or at the end of the plate-like fire baffle. In one embodiment, the air openings are on several surfaces of the fire baffle. The location and number of the air openings are selected to suit each situation. This allows the fire event to be optimized in different situations.

For example, the air volumes of primary and secondary air, as well as possible tertiary air, can be controlled to be optimal for a fire event by choosing the location and number of air openings appropriately.

In one embodiment, the fireplace comprises both primary and secondary air ducts. The fire damper according to the invention can then be connected in flow communication with either the primary and/or secondary air duct. Thus, the fire damper can be used to supply either primary or secondary air or both to the fire event.

In one embodiment, the fireplace comprises both primary, secondary and tertiary air ducts. The fire damper according to the invention can be connected in flow communication with either the primary, secondary or tertiary air duct or more of these ducts. Thus, the fire damper can be used to supply primary, secondary or tertiary air or more of these to the fire event.

In one application, the interior of the fire damper is a tertiary air duct. In another application, the interior of the fire damper is connected to a tertiary air duct. In this way, tertiary air is supplied to the fire event from the air openings of the fire damper. Tertiary air

air = is supplied to the combustion event = slightly later than — primary — secondary air. This enhances the combustion of unburned gases.

In one embodiment of the invention, the amount of primary air is regulated by a primary air shut-off device. In one embodiment of the invention, the amount of secondary air is regulated by a secondary air shut-off device. In one embodiment of the invention, the amount of tertiary air is regulated by a tertiary air shut-off device.

In one embodiment of the invention, the amount of primary air can be adjusted — separately, completely independent of any possible adjustment of secondary and/or tertiary air.

The primary air duct can even be closed completely if desired.

In one embodiment of the invention, the amount of secondary air can be adjusted separately, completely independent of any adjustment of primary and/or tertiary air.

The secondary air duct can even be closed completely if desired.

In one embodiment of the invention, the amount of tertiary air can be adjusted separately, completely independent of any adjustment of primary and/or secondary air.

The tertiary air duct can even be closed completely if desired.

In one application, the primary air volume can be adjusted independently of the secondary and tertiary air, and the combined volume of secondary and tertiary air is adjusted together, independently of the primary air volume. In one application, the primary air duct is separate from the common secondary and tertiary air duct. In one application, the primary air volume is adjusted by a primary air shut-off device, and the combined volume of secondary and tertiary air is adjusted by a secondary and tertiary air shut-off device.

In one application, the fire guide is attached to the upper part of the firebox wall. In another application, the fire guide is attached to the firebox wall and at an angle to the wall so that the fire guide forms a roof of the firebox for at least part of the area between the firebox walls. The fire guide can be arranged horizontally or at an angle to the horizontal, as needed. The temperature in the upper part of the firebox easily rises so high that traditional fire guides often do not last very long in use. A cooled fire guide is more durable.

In one application, the amount of primary air directed to the fireplace grate is controlled manually by opening and closing the ash box. The primary air duct then passes through the ash box. In one application, the ash box lid is at least essentially airtight when closed, so that the flow of primary air can be stopped completely by closing the ash box.

In one embodiment, part of the secondary and/or tertiary air duct is arranged under and/or to the side of the firebox and/or ash box. The air transport can thus be arranged in a space-saving manner. In one embodiment, this route is the most direct route from the air intake openings in the front wall of the fireplace to the lower edge of the hollow side or rear wall of the firebox and — to the interior.

In one application, the fireplace is a stove with a stone space intended for stove stones. The stone space is in heat transfer connection to the flue gas duct for heating the stove stones and thus to the hot gases flowing inside the flue gas duct during use of the stove. —The stove stones are thus heated by the heat taken from the hot gases. The gas flows controlled by the invention result in very low stove emissions while fuel consumption is low.

The invention and its possible applications achieve several advantages over traditional fireplaces. The temperature of the hollow walls and the firebox can now be controlled.

The service life of the fireplace structures increases. Flame guides can be used to control the flame and to supply air to the fire in a controlled manner. Turbulence and the efficiency of the fire process can be improved. A normal type of grate can be used at the bottom of the firebox, through which the primary air coming in can be adjusted separately from the rest of the air.

Secondary and tertiary air can be controlled together or separately. The amount of air required for a fire event can be directed to the right point in the fire process.

The temperature of the flue gas remains sufficient for ignition when mixed with oxygen-rich air at different points in the fireplace. More controlled turbulence formation promotes reaching the optimal temperature at different points in the combustion process. Effective turbulence causes efficient mixing of air and flue gas. The progression of flue gases in the process without a flame is effectively prevented. This achieves the cleanest and most complete combustion possible. Studies have shown that too high or low a combustion temperature promotes, among other things, the formation of soot. The shape of the firebox and air guide, as well as the location and size of the air holes, ensure the correct combustion process almost regardless of the user's actions. With precise air volume and flow control, the amount of waste air flowing past the combustion process can be minimized. With precise air volume and flow control, the draft in the fireplace is achieved, even though relatively little air is supplied. The combustion process is easy to adjust manually by monitoring the combustion and flame formation through a hatch or window. Operation with incorrect air duct settings is quickly visible in the flame formation. The user's main task is to adjust the amount of air needed for ignition and the total amount of combustion air. The simplicity of the adjustment also allows for easy installation of an auxiliary device, such as an electronic control device, which makes optimal clean fire even more independent of user intervention.

BRIEF DESCRIPTION OF THE PATTERNS

The invention will be described in more detail below with reference to the accompanying schematic drawing, in which

Figure 1 shows a side cutaway view of a stove according to the invention,

Figure 2 shows a front view of the firebox door of the stove of Figure 1,

Figure 3 shows a cutaway view of the stove in Figure 1 from the front,

Figure 4 shows a side cutaway view of the heater according to the invention,

Figure 5 shows a cutaway view of the front of the heater in Figure 4,

Figure 6 shows a side cutaway view of a fireplace or fireplace core according to the invention,

Figure 7 shows a front section of the fireplace or fireplace hearth of Figure 6,

Figure 8 shows a side cutaway view of a storage fireplace according to the invention,

Figure 9 shows the ash door of the fireplace of Figure 8, viewed from the front,

Figure 10 — shows Figure 8 cut away from the front of the fireplace,

DETAILED DESCRIPTION OF EXAMPLES OF PATTERNS

For the sake of clarity, some corresponding parts are given the same reference numbers in different figures and embodiments.

The figures use arrows to schematically depict different gas flows in the furnaces. The arrows drawn in a circle depict the turbulence of the flows.

Figures 1-3 show a stove 1 according to the invention. Figures 4 and 5 show a heater 2 according to the invention. Figures 6 and 7 show a fireplace or fireplace core 3 according to the invention. Figures 8-10 show a storage fireplace 4 according to the invention. The stove 1, the heater 2, the fireplace or fireplace core 3 and the storage fireplace 4 are intended for burning solid fuel, such as firewood 5. Each fireplace 1-4 is unique in its structure and function, but there are also many similarities. Each fireplace 1-4 comprises a firebox 6, which has side walls 7 and 8, a rear wall 9 and a front wall.

In the examples in the pictures, the opening door 10 serves as the main front wall of the firebox.

The fireplaces of Figures 1-4 have a primary air duct 11, a secondary air duct 12 and a tertiary air duct 13, through which air is brought to different points of the combustion process. In the examples of the figures, primary air is brought to the combustion process through a grate 14, secondary air through secondary air openings 15 and tertiary air through tertiary air openings 16. A flue gas duct 18 originates from the upper part 17 of the firebox, through which the gases are led out of the firebox.

Each fireplace 1-4 comprises a fire guide 21 for guiding gases in the firebox and/or flue gas duct. The fire guide has walls 22, 23, 24 and between them an empty — inner space 25, in which air can flow. In the examples, the interior 25 is connected to the tertiary air duct 13. At least one fire guide wall 22, 23, 24 has tertiary air openings 16 for directing air from the interior of the fire guide to the firebox 6 or to the flue gas duct 18. —Each fireplace 1-4 comprises at least one hollow firebox wall 7, 8, 9. The interior parts 26 of the hollow walls are connected to the secondary air duct 12. Thus, the hollow wall 7, 8, 9 also functions as a secondary air duct 12. In the upper parts of the hollow walls 7, 8, 9, typically above the firewood 5, there are secondary air openings 15 for directing air from the interior part 26 of the hollow wall to the firebox 6 as secondary air.

In the examples, the interior space 25 of the fire guide 21 is connected to the interior space 26 of the hollow wall of the firebox. The tertiary air to the fire guide 21 is therefore taken from the secondary air duct 12. It can therefore be said that in the examples, the interior space 26 of the hollow wall functions as both the secondary and tertiary air ducts 12 and 13.

The stove 1 of Figures 1-3 has a firebox door 10. At its upper edge there is a window 32, through which the combustion process in the firebox 6 can be observed. At the lower edge of the door 10 there are adjustable air intake openings 33. Behind the air intake openings there is an air space 40, from which the combustion air required by the fireplace is taken. The primary, secondary and tertiary air ducts 11 and 12 originate from the air space. By adjusting the size of the openings 33, the flows of both primary, secondary and tertiary air into the air ducts 11 and 12 are simultaneously controlled. The size of the primary air duct 11, i.e. the amount of primary air directed to the grate 14, is also controlled manually by opening and closing the ash box 34.

The inner parts 26 of the hollow walls 7, 8 and 9 of the stove 1 are connected to the secondary air duct 12. Thus, the hollow side walls 7 and 8 and the rear wall 9 also function as the secondary air duct 12. In the upper part of the walls there are secondary air openings 15 for directing air from the inner part 26 of the hollow wall to the firebox 6 as secondary air. Part of the secondary air duct 12 is arranged under the firebox 6 and the ash box 34 and part on the sides of the firebox.

The fire guide 21 of the stove 1 is connected to the upper edge of the hollow side wall 7 of the firebox. The air to the fire guide 21 comes from the hollow side wall 7 of the firebox. The secondary air duct 12 therefore also functions as a tertiary air duct 13. The horizontal upper wall 24 of the fire guide has tertiary air openings 16 for directing air from the inner part 25 of the fire guide to the firebox 6 as tertiary air. The fire guide 21 is arranged in the flue gas duct 18 just before the stove level 31. In this way, the fire guide 21 optimally directs the hot gases flowing from the firebox 6 under the stove level 31, and the tertiary air supplied from the fire guide ensures turbulence of the gases under the stove level and thus the optimality of the combustion process.

The stove 2 of Figures 4 and 5 has a door 10 corresponding to the firebox door of Figure 2. At its upper edge there is a window 32 through which the combustion process in the firebox 6 can be observed.

At the bottom edge of the hatch 10 there are adjustable air intake openings 33. Behind the air intake openings there is an air space 40, from which the combustion air required by the fireplace is taken. The primary, secondary and tertiary air ducts 11 and 12 depart from the air space 40. By adjusting the size of the openings 33, the flows of both primary, secondary and tertiary air into the air ducts 11 and 12 are simultaneously controlled. The size of the primary air duct 11, i.e. the amount of primary air directed to the grate 14, is also controlled manually by opening and closing the ash box 34.

The inner parts 26 of the hollow walls 1, 8 and 9 of the heater 2 are connected to the secondary air duct 12. Thus, the hollow side walls 7 and 8 and the rear wall 9 also function as the secondary air duct 12. In the upper part of the walls there are secondary air openings 15 for directing air from the inner part 26 of the hollow wall to the firebox 6 as secondary air. Part of the secondary air duct 12 is arranged under the firebox 6 and the ash box 34 and part on the sides of the firebox.

The fire guide 21 of the stove 2 is arranged in the upper part 17 of the firebox directly above the grate 14 and the firewood 5 to be burned on it. The plate-like fire guide 21 is attached to the upper edge of the vertical hollow rear wall 9 of the firebox in a roughly horizontal plane. Air enters the fire guide 21 from the hollow rear wall 9 of the firebox. The plate-like fire guide 21 forms, as it were, the main horizontal roof in the upper part 17 of the firebox.

The fire guide 21 spreads the gases towards the front wall 10 and the side walls 7 and 8 of the fire chamber before the gases flow between the fire guide 21 and the walls 7, 8 and 10 into the flue gas duct 18. Tertiary air air openings 16 are formed in the horizontal lower wall 22 and the vertical end wall 23 of the fire guide to direct air from the inner part 25 of the fire guide to the fire chamber 6 as tertiary air. In this way, the fire guide 21 directs the hot gases flowing from the fire chamber 6, ensures the mixing of the gases with the tertiary air and thus the optimality of the combustion process.

At the top of the heater 2 there is a stone space 41 intended for heater stones (not shown). The flue gas channel 18 passes through the stone space 41. The stone space 41 and the heater stones placed therein are in heat transfer connection with the flue gas channel 18 and with the hot gases flowing inside the flue gas channel 18 during operation of the heater 2. The heater stones are therefore heated by the heat taken from the hot gases.

The fireplace or fireplace hearth 3 of Figures 6 and 7 has a firebox door 10. At its upper edge there is a window through which the combustion process in the firebox 6 can be observed.

The size of the primary air duct 11, i.e. the amount of primary air directed to the grate 14, is controlled manually by opening and closing the ash box 34 below the door 10. Below the ash box 34 is an air intake opening, from which air is directed to the secondary air duct 12 and from there to the tertiary air duct 13. The size of the air duct 12 and thus the flow of secondary and tertiary air is controlled by controlling the closing device 35 below the fireplace.

The inner part 26 of the hollow rear wall 9 of the fireplace or fireplace core 3 is connected to the secondary air duct 12. Thus, the hollow rear wall 9 also functions as a secondary air duct 12. The upper part of the wall 9 has secondary air openings 15 for directing air from the inner part 26 of the hollow wall to the firebox 6 as secondary air. A part of the secondary air duct 12 is arranged under the firebox 6 and the ash box 34.

The fire guide 21 of the fireplace or fireplace core 3 is arranged in the upper part 17 of the firebox directly above the grate 14 and the firewood 5 to be burned on it. The plate-like fire guide 21 is attached to the upper edge of the hollow rear wall 9 of the firebox. Air enters the fire guide 21 from the hollow rear wall 9 of the firebox. The fire guide 21 is attached at an angle to the vertical rear wall 9, i.e. diagonally, so that its front edge 27 is somewhat higher than the rear edge 28. The sides 29 of the fire guide are attached to the side walls 7 and 8 of the firebox.

The fire guide 21 forms a roof that rises towards the front wall 10 of the firebox — at the top 17 of the firebox. The fire guide 21 spreads the gases towards the front wall 10 before the gases flow between the fire guide 21 and the front wall 10 into the flue gas duct 18.

Tertiary air inlets are formed in the lower wall 22 and the end wall 23 of the fire guide.

openings 16 for directing air from the inner part 25 of the fire guide to the fire chamber 6 as tertiary air. In this way, the fire guide 21 directs the hot gases flowing from the fire chamber 6, ensures mixing of the gases with the tertiary air and thus the optimality of the combustion process.

The storage fireplace 4 of Figures 8—10 has a firebox door 10. At its upper edge there is a window through which the combustion process in the firebox 6 can be observed. Below the door 10 there is an openable ash door 36 with adjustable air intake openings 33.

Behind the air intake openings is an air space 40, from which the combustion air required by the fireplace is taken. The primary, secondary and tertiary air ducts 11 and 12 originate from the air space. By adjusting the size of the openings 33, the flows of primary, secondary and tertiary air into the air ducts 11 and 12 are simultaneously controlled. The amount of primary air directed to the grate 14 can also be controlled manually by opening and closing the ash box 34.

The inner part 26 of the hollow rear wall 9 of the fireplace 4 is connected to the secondary air duct 12. Thus, the hollow rear wall 9 also functions as a secondary air duct 12. The upper part of the wall 9 has secondary air openings 15 for directing air from the inner part 26 of the hollow wall to the firebox 6 as secondary air. A part of the secondary air duct 12 is arranged under the firebox 6 and the ash box 34.

The fire guide 21 of the fireplace 4 is arranged in the upper part 17 of the firebox directly above the grate 14 and the firewood 5 to be burned on it. The plate-like fire guide 21 is attached to the upper edge of the hollow rear wall 9 of the firebox. Air to the fire guide 21 comes from the hollow rear wall 9 of the firebox. The fire guide 21 is attached at an angle to the vertical rear wall 9, i.e. diagonally, so that its front edge 27 is somewhat higher than the rear edge 28. The sides 29 of the fire guide are tightly attached to the side walls 7 and 8 of the firebox.

The fire guide 21 forms a roof, as it were, rising towards the front wall 10 of the firebox at the top 17 of the firebox. The fire guide 21 spreads the gases towards the front wall 10 before the gases flow between the fire guide 21 and the front wall 10 into the flue gas duct 18.

Tertiary air openings 16 are formed in the lower wall 22 and the vertical end wall 23 of the fire guide to direct air from the inner part 25 of the fire guide to the fire chamber 6 as tertiary air. In this way, the fire guide 21 directs the hot gases flowing from the fire chamber 6, ensures the mixing of the gases with the tertiary air and thus the optimality of the combustion process.

The reversible damper 37 can be opened and closed using the handle 38. If the damper 37 is open, the flue gases travel from the top of the combustion chamber straight up to the flue gas duct 18. If the damper 37 is closed, the flue gases travel from the top of the combustion chamber along a longer winding path 39 to the flue gas duct 18, while heating the storage firebox structures more efficiently.

The invention is not intended to be limited to the examples presented, but the scope of protection is determined by the independent patent claims. The dependent claims present several advantageous applications of the invention.

Claims (18)

PATENT CLAIMS 1. A solid fuel fireplace (1, 2, 3, 4), comprising — a firebox (6) having walls (7, 8, 9); — an at least partially metallic or masonry or refractory mass flue gas duct (18) for conducting gases out of the firebox; — primary and secondary air air ducts (11, 12) for conducting air in connection with a fire event in the fireplace at several different points in the fire event, whereby the secondary air air duct (12) is arranged to conduct air in connection with a fire event in the fireplace in the general flow direction of the flue gases at least mainly after the primary air; — adjustable | air intake openings (33), from which the combustion air required by the fireplace, i.e. primary and secondary air, is taken, and by adjusting the size of the air intake openings (33) of which the primary and secondary air flows in the air ducts (11, 12) of the fireplace are simultaneously controlled; characterized in that — behind the air intake openings (33) inside the fireplace there is an air space (40), from which the combustion air required by the fireplace is taken, and from which the primary and secondary air air ducts (11, 12) exit, and that — the entire air space (40) of the primary air air duct (11) between the firebox (6) is arranged to be adjustable, in order to control the primary air flow separately from the secondary air flow. 2. A fireplace (1, 2, 3, 4) according to claim 1, wherein — at least one wall (7, 8, 9) of the firebox is hollow and the interior space (26) of the wall is connected to a secondary air duct (12) so that the hollow wall functions as an air duct, and at least one hollow wall (7, 8, 9) of the firebox has at least one secondary air = air opening (15) for directing air from the interior of the hollow wall (26) into the firebox (6) as secondary air. 3. A fireplace (1, 2, 3, 4) according to claim 1 or 2, characterized in that it comprises — a tertiary air duct (13) for conducting air in connection with the fire event of the fireplace in the general flow direction of the combustion gases at least mainly after the primary and secondary air. 4 A fireplace (1, 2, 3, 4) according to claim 3, characterized in that it comprises — a fire guide (21) for directing gases in the fire chamber (6) and/or in the flue gas duct (18), which fire guide (21) is at least partially hollow, and the empty interior space (25) of the fire guide is connected to the tertiary air duct (13) for conducting air from the air duct to the interior space of the fire guide, and the interior space (25) of the fire guide (21) is surrounded by walls (22, 23, 24) of the fire guide, at least one of which has at least one air opening (16) for directing air as tertiary air from the interior space of the fire guide to the fire chamber (6) and/or to the flue gas duct (18). 5. A fireplace (1, 2, 3, 4) according to any one of the preceding claims, characterised in that — tertiary air is additionally taken from adjustable air intakes (33), and by adjusting the size of the air intakes (33) the primary, secondary and tertiary air flows in the air ducts (11, 12, 13) of the fireplace are simultaneously controlled. 6. A fireplace according to any one of the preceding claims, characterized in that it comprises — an openable and closable ash box (34) leading from the air space (40) to under the grate (14), by opening and closing which the size of the primary air duct (11) between the air space (40) and the firebox (6) can be adjusted. 7. A fireplace according to any one of the preceding claims, characterized in that all the combustion air required by the fireplace is taken from the air space (40). 8. A fireplace according to any one of the preceding claims, characterized in that all the combustion air required by the fireplace is taken into the air space (40) through adjustable air intake openings (33). 9. A fireplace according to any one of the preceding claims, characterized in that it comprises an openable and tightly closable fireplace door (10, 36) in which adjustable air intake openings (33) are arranged. 10. A fireplace according to claim 9, characterized in that the air space (40) is behind the door (10, 36) and the air intake openings (33). 11. A fireplace according to any preceding claim, characterized in that the same air duct (12) serves as an air duct for secondary and tertiary air. 12. A fireplace according to any one of the preceding claims, characterized in that it is a heater (2), fireplace (3), fireplace insert (3), storage fireplace (4), stove (1), stove or baking oven. 13. A fireplace according to claim 12, characterized in that the fireplace is a stove (2) which — comprises a stone space (41) intended for stove stones, which is in heat transfer connection with the flue gas duct (18) and with the hot gases flowing inside the flue gas duct (18) during use of the fireplace, for heating the stove stones. 14. A method in a solid fuel fireplace (1, 2, 3, 4) according to any one of the preceding claims 1-13, which method comprises at least the following step: — burning solid fuel in a fireplace chamber (6) having walls (7, 8, 9); — conducting gases out of the fireplace chamber through a flue gas duct (18) made at least partly of metal or masonry or of refractory mass; — conducting air through primary and secondary air ducts (11, 12) in connection with the fire event of the fireplace at several different points in the fire event, whereby the secondary air duct (12) is arranged to conduct air in connection with the fire event of the fireplace in the general flow direction of the flue gases at least mainly after the primary air, whereby — taking in the combustion air required by the fireplace, i.e. primary and secondary air, through adjustable air intake openings (33), — the primary and secondary air flows in the air ducts (11, 12) of the fireplace are simultaneously controlled by adjusting the size of the air intake openings (33); characterized in that — the combustion air required by the fireplace is taken from the air space (40) inside the fireplace behind the air intake openings (33), from which the primary and secondary air air ducts (11, 12) originate, — the size of the primary air air duct (11) is adjusted between the air space (40) and the firebox (6) and thus the primary air flow is controlled separately from the secondary air flow. 15. A method according to claim 14, characterized in that — the tertiary air required by the fireplace is taken into the air space (40) through adjustable air intake openings (33) and is further led along the tertiary air air duct (12, 13) leaving the air space (40) to the fireplace combustion event in the general flow direction of the combustion gases, at least mainly after the primary and secondary air. 16. A method according to claim 15, characterized in that — gases are guided in the firebox (6) and/or in the flue gas duct (18) of the fireplace by a fire guide (21), which is at least partially hollow, and the empty interior space (25) of the fire guide is connected to the tertiary air duct (12, 13) of the fireplace; — air is guided from the tertiary air duct (12, 13) to the interior space (25) of the fire guide; whereby — the fire guide (21) is cooled with air guided from the air duct (12, 13); — the interior space (25) of the fire guide (21) is surrounded by walls (22, 23, 24) of the fire guide, at least one of which walls has at least one air opening (16), through which air is guided as tertiary air from the interior space of the fire guide to the firebox (6) and/or to the flue gas duct (18). 17. A method according to any one of the preceding claims 14-16, characterized in that the size of the primary air duct (11) is adjusted to the air space (40) and the firebox (6). between opening and closing the ash box (34) leading from the air space (40) to under the grate (14). 18. A method according to any one of the preceding claims 14-17, characterized in that all the combustion air required by the fireplace is taken into the air space (40) through adjustable air intake openings (33).