EP2775210A1 - Oven - Google Patents

Abstract

The furnace (1) has a combustion chamber (2) having a convection heat region (3) for generating convection heat from a heat radiation area (4) for radiating generated heat in combustion chamber to heat the air of heat radiation area with the radiated heat. The furnace has two operating states, and in the first operating state, a fan (5) is operated to direct warm air from heat region by convection to the outside environment, and in the second operating state, the fan is operated to direct the warm air partially into the remote area of furnace. Independent claims are included for the following: (1) a heating system; and (2) a method for controlling heating system.

Description

FIELD OF THE INVENTION

The present invention relates generally to furnaces for heat generation, and more particularly to a convection heat-generating oven, a heating system with such an oven, and a method of controlling such a heating system.

BACKGROUND OF THE INVENTION

There are generally known stoves for heat generation, which are particularly suitable for the combustion of wood, such as logs or pellets. Such ovens are typically also used in living quarters, e.g. set up in the form of a stove.

Basically, two different types of furnaces are known, namely, on the one hand, which deliver heat as convection heat to the environment of the furnace and, on the other hand, those in which a fan in the oven gives off heated air to the environment of the furnace. With convective heat, the air heated by the oven rises by natural convection.

Stoves that use the convection heating principle are typically very quiet because they do not require a fan. In addition, the convection results in a quiet flow of heated air, so that no dust or other light particles in the vicinity of the furnace are whirled up.

Furnaces that use a blower to deliver the heated air to the environment produce a noise during operation which is primarily caused by the blower. In addition, the air flow generated by the blower is typically significantly stronger than the convection flow, so that dust and other light particles can be swirled up.

In particular, stoves that are placed in living rooms, often serve as an eye-catcher, although the heat emitted from the oven is sometimes not needed. In addition, ovens often have a heating capacity higher than that required in the room in which they are installed.

The object of the present invention is to provide an improved furnace for heat generation, in particular a wood-burning stove such as a log burning stove or pellet stove, a heating system with such a furnace and a method for controlling such a heating system.

SUMMARY OF THE INVENTION

According to a first aspect, the present invention provides a furnace for heat generation, in particular a wood-burning stove, such as a log-burning stove or pellet stove, in accordance with independent claim 1. In a second aspect, the present invention provides a heating system with a furnace according to the first aspect in accordance with claim 8. In a third aspect, the present invention provides a method of controlling the heating system of the second aspect.

Further aspects and features of the present invention will become apparent from the dependent claims, the accompanying drawings and the following description of preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWING

• Fig. 1 ein Ausführungsbeispiel eines Pelltofens in Übereinstimmung mit der vorliegenden Erfindung in einer dreidimensionalen Schnittansicht veranschaulicht;
• Fig. 2 den Pelletofen in einer vertikalen Querschnittansicht zeigt;
• Fig. 3 den Pelletofen in einer Schnittansicht von oben darstellt;
• Fig. 4 ein Ausführungsbeispiel eines Heizsystems mit einem Pelletofen nach den Fig. 1 bis 3 zeigt; und
• Fig. 5 ein Verfahren zur Steuerung des Heizsystems nach Fig. 4 zeigt.

Embodiments of the invention will now be described by way of example and with reference to the accompanying drawings, in which:

• Fig. 1 an embodiment of a Pelltofens in accordance with the present invention in a three-dimensional sectional view illustrated;
• Fig. 2 shows the pellet stove in a vertical cross-sectional view;
• Fig. 3 shows the pellet stove in a sectional view from above;
• Fig. 4 an embodiment of a heating system with a pellet stove after the Fig. 1 to 3 shows; and
• Fig. 5 a method for controlling the heating system after Fig. 4 shows.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the Fig. 1 to 3 is an embodiment of a pellet stove 1 in accordance illustrated with the present invention. Before a detailed description follows first general explanations to the embodiments and their advantages.

The embodiments relate to a furnace for heat generation, which is designed to burn a fuel in a combustion chamber. In principle, all types of fuels are considered, which are made of biomass, but also fuels such as gas, oil, lignite, wood or hard coal and the like.

In particular, the further description also relates, without the present invention being restricted thereto, to a wood-burning stove, such as e.g. a log burning stove or in particular a pellet stove, which is designed, for example, as a stove or the like and typically in a (living) room can be set up.

In the exemplary embodiments, a furnace for heat generation, in particular a wood-burning stove, such as a logwood stove or pellet stove, comprises a combustion chamber with a rear wall and two side walls. Compared to the rear wall of the combustion chamber is typically closed with an oven door. The oven may be equipped with firebricks or the like.

The oven further includes a convection heat area for generating convection heat. Convective heat is generated when air is heated by heat radiation and the heated air rises due to convection. The convection-rising air is typically discharged through a corresponding outlet of the oven to the outside of the oven, thereby heating the environment of the oven. The air that is heated can also come from the outside of the oven. In some embodiments, the air to be heated comes from a fresh air supply, which removes the fresh air from an area remote from the furnace; For example, from another room or from outside the building in which the furnace is placed.

For heating the air, the furnace in the convection heat area has a heat radiation area for radiating heat generated in the combustion chamber. It is designed to heat air by the radiated heat from the heat radiation area, wherein the heated air flows away by convection from the heat radiation area and, for example, delivered to the outside of the furnace environment and it warms them.

The heat radiation region may preferably have a structure that guides heated air, such as ribs, channels, or the like. The heat radiation region, in some embodiments, is formed of metal or other suitable material that can withstand the temperatures typically encountered in an oven. It can also be thermally coupled to the combustion chamber. In some embodiments, the heat radiation area is located above the combustion chamber, i. either directly above the combustion chamber or (partially) offset to the combustion chamber but above the combustion chamber. The heat radiation region may also be configured directly, for example, on an upper side of the combustion chamber as ribs or the like in order to provide a large heat radiation surface for the air to be heated.

In some embodiments, the heat radiation region or region also extends partially around the combustion chamber, such that air flowing from bottom to top along one side of the combustion chamber and through the confectioning heat region is heated.

The oven further includes a fan arranged to at least partially discharge the warm air from the convection heat area during operation. The blower can thereby suck the warm air out of the ready-made heat area and / or blow the air through the convection heat area in a targeted manner.

If the fan removes the warm air from the convection heat range, typically the fan does not interfere with the air flow of the air to be heated through the convection area since the fan may be located behind the convection area from the point of view of air flow. The flow path is therefore such that cold air is heated in the vicinity of the combustion chamber in the convection region, further rises in the convection region and is strongly heated in the heat radiation region. Depending on the structural condition, the flow path of the air to be heated and the heated air can also be guided, for example through channels, guide bleach and the like.

As blower come various known types of blower into consideration, such as radial fan and cross-flow fan, the present invention is not limited to a particular Blower type is limited. In some embodiments, more than one fan is present. Thus, for example, the air flow can be divided into two fans or one fan is arranged in front of the air and another after the heat radiation area.

The oven has two operating states. In a first operating state, the fan is de-energized and out of service and the oven releases convective heat in the form of the warm air, which has been heated in the heat radiation area, to the outside environment of the oven. Thus, in the first mode of operation, in some embodiments, the oven operates as a convection heat oven, which does not require the operation of a fan, and where the air is heated due to (natural) convection and delivered to the outside environment around the oven. In this case, the oven or the convection heat range is designed so that there is no overheating even when the blower is switched off.

In a second operating state, the fan is in operation, so it is powered, and at least partially directs the warm air in one of the remote area. The remote area may be a space that differs from the installation space of the oven, or it may be an area in the room in which the oven is installed, but in which e.g. the convection heat is not delivered, etc. In some embodiments, in the second operating state of the furnace, the heated air is not completely discharged from the fan, but still some of the heated air passes through the (natural) convection to the outside environment of the furnace.

The switching of the furnace in the first and second operating state, that is, e.g. also switching on the blower, can be done manually or by a controller, as described below. With manual switching of the furnace, a corresponding switching means is provided in some embodiments.

In some embodiments, an additional deflection means is provided, which is designed so that it passes in the first operating state of the furnace, the warm air through a convection air opening of the furnace, while in the second operating state of the furnace, the warm air

To the fan, in some embodiments, a corresponding warm air duct for the heated air is mounted to direct the warm air from the convection heat range targeted in the remote area.

The furnace may be switched to the first or second operating state depending on a temperature in the remote region, in some embodiments. For this purpose, it can have a controller which is set up in such a way that it switches on the fan when a temperature value originating from a temperature measurement in the remote area falls below a setpoint value connected in the controller.

The blower can be arranged above the combustion chamber, for example in the convection heat range in the immediate vicinity of the heat radiation region. In some embodiments, the fan is disposed adjacent the heat radiation area. As already stated above, the fan can be arranged from the perspective of the heated air before or after the heat radiation region. In some embodiments, the heat radiation region is disposed directly above the combustion chamber, and the blower is disposed adjacent to the heat radiation region such that the blower itself is not disposed above the combustion chamber. In this way, the heat radiation from the combustion chamber is transmitted to the heat radiation area in a particularly effective manner, and the blower itself is not arranged directly in the hot zone above the combustion chamber.

In some embodiments, the oven is configured as a pellet stove and includes a pellet container. The blower is located in the area of the pellet container. As a result, the pellet container shields the heat radiation emitted by the combustion chamber with respect to the blower and thereby protects the blower against overheating. The pellet container may have a recess and the fan may be at least partially disposed in the recess. In this embodiment, the blower can be particularly effectively shielded against the heat radiation of the combustion chamber. A pellet stove uses as fuel pellets, which are small cylindrical wood pellets. The pellet container is typically filled with pellets during operation of the pellet stove, so that pellets lying between the combustion chamber and the fan also contribute to the shielding of the heat radiation emitted by the combustion chamber.

Some embodiments relate to a heating system with an oven as described above for heating at least two rooms. The stove is installed in a first room and heats the first room with convection heat in the first operating state. In the second operating state, the oven heats the second room by passing the warm air into the second room. As stated above, in the second operating state, the fan is turned on and accordingly, as described above, directs the warm air from the convection heat area, for example, through a hot air duct into the second room to heat it.

For the control, in some embodiments, the heating system includes a controller and a thermostat. The thermostat is located in the second room and connected to the controller. The controller switches the oven to the second operating state when the temperature determined by the thermostat in the second room falls below a setpoint set in the thermostat. The controller may be placed in the oven or outside the oven and connected to the oven by appropriate control lines. It can also be housed in a housing together with the thermostat. In some embodiments, the controller has a microprocessor and (read) memory. Control commands, threshold values and the like can be stored in the memory (read-only memory). In addition, the controller can also be set up to execute a method, for example the one described below.

Some embodiments relate to a method of controlling a heating system, as described above. The method includes starting a combustion in the combustion chamber of the furnace. For this purpose, in some embodiments, the oven is equipped with a corresponding ignition mechanism and a fuel supply, so that combustion in the oven can be started automatically. Next, we detect a first temperature in the first room and / or a second temperature in the second room. The fan of the furnace is controlled in dependence on the detected first and / or second temperature. In this case, various control scenarios can be provided, as explained below.

In one scenario, the fan is turned on when the second temperature is below a threshold regardless of the amount of the first temperature. In another scenario, the fan is not turned on until when the first temperature is above a threshold, that is, when the first space has reached the desired temperature and the second temperature is below a threshold. In another scenario, the blower (also) is turned on when the first temperature is above another threshold, that is, when it is warmer in the room than desired. This may be useful if it is desired that the temperature in the first room remains stable at a setpoint temperature, while, for example, the temperature in the second room is of secondary importance. Also mixed forms of the described scenarios are realized.

Coming back to the Fig. 1 to 3 These illustrate an embodiment of a pellet stove 1, which is adapted for the combustion of pellets.

The pellet stove 1 has a combustion chamber 2 and, above the combustion chamber 2, a convection heat region 3, which also extends laterally along a side wall of the combustion chamber 2 and is arranged in the heat exchanger 10. In the convection heating area 3, a heat radiation area 4 is formed from ribs 12, which are arranged directly on the upper side of the combustion space 2 and in this way are thermally coupled to the combustion space 2. The pellet stove 1 has on its upper side air openings through which warm air which has been heated in the convection heating area 3 can flow out.

In addition to the combustion chamber 2, a pellet container 6 is arranged. In the pellet container 6 is an inclined screw conveyor 8, which conveys pellets from the pellet container 6 into the combustion chamber 2. Below the pellet container 6, a flue gas fan 9 is arranged, which derives in the combustion chamber 2 emerging flue gas via a flue gas outlet. In the upper half of the pellet container 6, a recess 7 is formed, in which a convection air blower 5 is arranged. The recess 7 has a trapezoidal cross-section and is thereby adapted to the outer shape of the convection air blower 5.

The convection air blower 5 in the present embodiment is a radial blower, and is arranged to suck in air heated in the heat radiation area 4 from the heat radiation area 4 and to discharge it through an outlet 11. In addition, it is arranged so that a motor of the convection air blower 5 points in the direction of the recess 7 of the pellet container 6.

The ribs 12 of the heat radiation area 4 are arranged such that channels formed between them extend in the direction of the convection air blower 5. Thereby, the convection air blower 5 can suck the air directed between the ribs 12 of the heat radiation area 4.

Opposite a side wall of the combustion chamber 2, as mentioned above, the heat exchanger 10 is arranged at a distance. The heat exchanger 10 is designed plate-shaped and has an area which corresponds substantially to the area of the side wall of the combustion chamber 2, with respect to which it is arranged. Between the heat exchanger 10 and the opposite side wall of the combustion chamber 2, a channel 13 is formed by the spacing, rises in the air during operation of the pellet stove 1 due to convection and is heated by the heat radiation emitted from the combustion chamber 2. At the upper end of the channel 13, the air is deflected and enters the heat radiation region 4 and between the ribs 12 and is further heated there. On top of the pellet stove 1 convection air openings through which the heated air can flow.

A heating system 20, which has a pellet stove 1, as above in connection with the Fig. 1 to 3 is described below with reference to Fig. 4 explained.

The pellet stove 1 is in a first room 21, hereinafter referred to as installation room 1, set up. At the outlet 11 of the fan 5 of the pellet stove 1, a hot air duct 23 is mounted, which leads into a side room 22. In the side room 22 is a thermostat 24th

The heating system has a controller 25 mounted or integrated in the vicinity of the pellet stove 1 and connected to both the pellet stove 1 and the thermostat 24.

The thermostat 24 has a temperature measuring means which determines the temperature in the side room 22. In addition, the thermostat 24 has a setting means with which a user can set a target temperature for the side room 22. If the determined by the thermostat 24 room temperature of the subspace 22 below the set temperature setpoint, the thermostat 24 sends a corresponding signal to the controller 25th

The controller 25 controls the pellet stove 1 and turns on the fan 5 of the pellet stove 1 when it has received the signal from the thermostat 24 that the room temperature determined by the thermostat 24 in the side room 22 is below the setpoint set to it.

As stated above, the fan 5 sucks the warm air from the heat convection region 3 and directs it from the outlet 11 into the hot air duct 23 and, in turn, into the auxiliary space 22 and heats it.

If the controller 25 does not receive a corresponding signal from the thermostat 24, the fan 5 remains switched off and the pellet stove 1 heats the installation space 21, as described above, with the warm air flowing out by natural convection. In a further embodiment (not shown), the pellet stove 1 has an additional fan which, depending on the control mode, can assist the delivery of the warm convection air into the installation room 22.

A general method for controlling the heating system Fig. 4 with a pellet stove after the Fig. 1 to 3 that may be implemented in a controller, such as the controller 25, is associated with Fig. 5 described.

In a first step 30, combustion in the combustion chamber 2 of the furnace 1 is started. For this purpose, the screw conveyed 8 pellets in the combustion chamber 2 and an igniter ignites the pellets in the combustion chamber 2. The air supply to initiate the combustion in the combustion chamber 2 is also adjusted accordingly. Next, in a step 31, for example, by the thermostat 24, a room temperature in the adjacent room 22 is determined.

The fan 5 of the furnace 1 is now, as described above, controlled in a further step 32 in response to the detected room temperature. The process is repeated at predetermined time intervals.

In addition, as stated above, in some embodiments, the room temperature in the installation room 21 of the pellet stove 1 is detected, and the pellet stove 1 is controlled according to the room temperature in the installation room 21 as stated above. For this purpose, either a further thermostat may be mounted in the installation room or a corresponding temperature detection and temperature setting is provided in the pellet stove 1.

Claims (11)

Furnace for heat generation, in particular wood-burning stove, such as log burning stove or pellet stove, comprising: a combustion chamber (2), a convection heating section (3) for generating convection heat having a heat radiating section (4) for radiating heat generated in the combustion chamber (2) and adapted to heat air by the heat radiated from the radiating section (4), the heated one Air by convection from the heat radiation area (4) flows away, and a fan (5) arranged to at least partially discharge the warm air from the convection heat zone (3) during operation, wherein the furnace has two operating states, in a first operating state the fan (5) is out of operation and the furnace diverts the warm air from the convection heat zone (3) by convection to the external environment and in a second operating state the fan (5) in operation, and it at least partially diverts the warm air to an area remote from the furnace. A heat generation furnace according to claim 1, further comprising a hot air duct (23) configured to direct the warm air into the remote area (22). Furnace for generating heat according to one of the preceding claims, wherein the blower (5) is arranged above the combustion chamber (2). A furnace for generating heat according to any one of the preceding claims, wherein the fan (5) is arranged adjacent to the heat radiation area (4). A furnace for generating heat as claimed in any one of the preceding claims, which is configured to switch the furnace to the first or second operating condition in response to a temperature in the remote region (22). A furnace for generating heat according to one of the preceding claims, wherein the furnace is designed as a pellet stove and comprises a pellet container (6) and the blower (5) is arranged in the region of the pellet container (6). A furnace for generating heat according to claim 6, wherein the pellet container has a recess (7) and the blower (5) is at least partially disposed in the recess (7). Heating system comprising an oven according to one of the preceding claims for heating at least two spaces (21, 22), the oven (1) being installed in a first space (21) and heating the first space (21) with convection heat in the first operating state and in the second operating state, heats the second space (22) by passing the warm air into the second space (22). A heating system according to claim 8, wherein the heating system comprises a controller (25) and a thermostat (24) disposed in the second space (22), the temperature in the second space (22) is determined and connected to the controller the controller (25) switches the oven to the second operating condition when the temperature in the second space (22) falls below a setpoint set in the thermostat. Heating system according to claim 8 or 9, wherein the furnace is designed as a log or pellet stove. A method of controlling a heating system according to any one of claims 8 to 10, comprising the steps of: Starting (30) combustion in the combustion chamber (2) of the furnace (1); Detecting (31) a first temperature in the first space (21) and / or a second temperature in the second space (22); Controlling (32) the fan (5) of the furnace (1) as a function of the detected first and / or second temperature.

Images