FI124929B - Solid fuel combustion device - Google Patents

Description

SOLID FUEL BURNER APPARATUS Technical field

Generally, the invention relates to an apparatus for supporting a fire load and controlling an airflow to a fire load to improve the efficiency of the combustion process and to reduce the discharge of polluting chimney gas particles.

Background technology EP0382107 describes a fireplace insert to improve combustion. It has an L-shaped air duct, the air outlet end of which is arranged at a distance above the support plane in such a manner that it can be arranged in the center of a fireplace fire, with the air inlet end lying outside the fireplace fire. The presented solution is intended for direct air in the center of a fire load. Depending on the amount, quality and placement of the fire load, the area of the fire load, directed air can reach may be limited. Further, the horizontal implementation of the air duct creates unfavorable conditions for the air flow because the pressure gradient at the inlet due to the incoming air may counteract the buoyant flow at the outlet end leading to diminished or nonexistent draft in the duct . US4213445 describes a fireplace combustion air duct apparatus including a main duct, which main duct is open at least partially along the bottom to receive air from the ash clean-out opening or other opening in the floor of the fireplace and also open at the forward end . Sliding into the forward end of the main duct is an adjustable duct open at least at the forward portion portion and configured to fit in telescoping fashion within the main duct. The adjustable duct is provided on the front end with a deflector plate for directing air from the duct to the rear of the fireplace so that logs or other combustible material on or directly above the duct will be directly exposed to the strong flow of air from the combustion air duct. The construction presents the same shortcomings as the previously mentioned EP0382107, as the directed air flow reaches only a small portion of the fire load reactive surface, the deflector is deflected, upwards away from the fire load because of the buoyant forces acting and the chimney draft. Further, the potentially long horizontal part of the duct in relation to the effective height of the duct may prove inefficient in providing a further advantage in providing air to the fire place as compared to a conventional grate opening. There is also the possibility to end up with an air lock in the region of the ash clean-out opening or other opening in the floor of the fireplace because of the heat expansion of the incoming air and the arrangement of the presented air duct. WO06072245 describes a wood burner inset for a wood burning stove, preferably with a closed combustion chamber. The inset is placed on the grate of the fireplace as the hinder entrainment of the cold air directly into the fire region but first circulating in the fireplace space. The air entrainment to the fire plum and the regions around the fire load happens from the fire place space with the exception that the sides were the obstructing plates of the construction resides, the air can only enter through the provided holes or over the edges of the plates. The inset thus merely provides an obstruction for the cold air straight in the fire region and the circulation of heated air in the fire place space confined between and above the inset rearmost horizontal plate and the front of the fire place. CA1197744 describes a newspaper burner insert for a fireplace with a perforated base plate for permitting air circulation and a connected back plate for supporting the newspaper. US 1684749 describes an open fireplace for providing the rear portion of the fuel with support on the grate and the front portion of the raised plate for heating the air passing through the air passage Underneath to the rear portion. US59968 describes a grate insert for a fireplace U.S.6405724 describes a fireplace grate for a stacking wood adjacent rear wall. US4329974 describes a fireplace grate insert with an attachment allowing a pivotal movement between a horizontal operative position and an upright inoperative position. GB601887 describes a basket insert for a fireplace for burning a slack together with conventional fuel. US4180054 describes a fireplace log tray insert with a suppressing base plate. CH669030 describes a fireplace with a slotted heat outlet separating the fireplace from a secondary chamber with a smoke outlet. Among other things for guiding incoming air, the aforementioned inventions are inadequate.

Summary of the invention

It is an object of present invention to implement such a solution that previously mentioned drawbacks of prior art could be diminished. In particular, the invention is implied to solve how to direct preheated air to the Burning region of a fire. The object of the present invention is to maximize the surface area of the fire load the directed air flow can reach, keeping the resulting mixture of pyrolysis products and air within the flammability limits of the mixture and as near as possible to the stoichiometric process. A further object of the present invention is to produce such a directed air flow by utilizing the relative arrangement of the limiting structures creating a retaining space for the fire load and the relative air passage and heat released by the ignited fire load.

The burning apparatus according to the present invention adapts itself to utilizing a large variety of solid fuels such as firewood, logs, charcoal, chips, pellets, peat etc.

The apparatus according to the present invention is an arrangement of limiting structures retaining a fire load and creating an air passage in relation to each other so that the differential pressure flow resulting from the buoyant flow and heat transfer increases the efficiency of the combustion process. Further, the apparatus according to the present invention with the resulting increased supply of air in the burning region of the fire and elevated temperature of the combustion and pyrolysis process decreases the amount of fine particles, carbon monoxide, volatile organic compounds, polycyclic aromatic hydrocarbons, black carbon etc. in the Escaping chimney gas.

Further, the invention relates to an apparatus that may be utilized in an open or enclosed fireplace of various sizes, over a grate or elevated above the bottom of a fireplace. The apparatus according to the present invention may be used in a fireplace having a grating, chimney or any other typical means for incoming air supply and exhaust gas passages and control notes. The apparatus of the present invention is further applicable to a burner on a suitable fire safe substrate without a primary enclosing fire place.

The apparatus according to the present invention consists essentially of a face plate having a first surface portion and a second surface portion. The first surface portion defines a first angle relative to the horizontal plane when the Burner is placed on a bottom or grate of a fire place. The second surface portion defines a second angle relative to the horizontal plane normal, that is, a vector in the vertical plane perpendicular to the horizontal plane. The face plate is supported in the fireplace to maintain the angles relative to the horizontal plane by the lower edge of the face plate first surface portion and optional supporting structures.

The first surface portion has a first angle relative to the supporting plane such that the surface rises towards the second surface portion relative to the horizontal plane. To achieve a favorable effect according to the present invention, said angle is preferably 10 ° or larger, but not more than 35 ° relative to the horizontal plane. The first surface portion defines a cavity between the underside of the surface and the fireplace bottom. The cavity is an air passage with a larger volume under the surface towards the second surface portion.

The second surface portion connects significantly to its lower edge to the upper edge of the first surface portion. The second surface portion is above and angled toward the first surface portion so that it defines an angle of zero degrees or larger relative to the normal of the horizontal plane. To achieve a favorable effect according to the present invention, said angle is preferably 0 ° or larger, but not more than 45 °. relative to the horizontal plane normal. The second surface portion defines a limiting structure for a fire load space. The burner apparatus according to the present invention has an upper opening defined at least by the second edge portion of the insertion of fire load and exiting flames and combustion gases. As the second surface portion connects to the first surface portion above the fireplace bottom, the fire load space is in communication with the air passage cavity.

The second surface portion acts as a support for the fire load. Further, the Burning apparatus according to the present invention may optionally be placed at a distance from the fire place wall, the Wall defining the rear face of the fire load space and an opening between the first and second surface connection and the wall. Similarly, the burner apparatus according to the present invention may be dimensioned and placed in a fire place so that the rear wall and one or two side walls of the fire place defines the rear and one or two side walls of the burner apparatus fire load space . Further, the apparatus according to the present invention may optionally have one or more structures selected from the rear face surface, the side wall, the bottom plate, and the elevating supports. These structures may act as both limiting structures and supporting structures for the present invention. For example, the apparatus according to the present invention may be constructed to have a fixed rear face surface which is attached to the face plate by using one or two side walls or a bottom plate having suitable openings for the passage of air to the air. passage cavity. If the fire place does not have a grate, the elevating supports may be used to raise the burner apparatus above to the fire place bottom in order to enable air to enter the burner apparatus air passage cavity.

The first and second surfaces of the face plate may be planar surfaces or surfaces defined by a continuous or gradual rotation about the center axis to form a face plate surface that coincides at its Imaginary side edges forming a uniform surface such as a surface having azimuthal projections in the horizontal plane of a sphere, ellipse, polygon, rectangle etc. Similarly a confining rear surface of the fire load space may be formed around the face plate, the rear surface is coagulated by rotation of a suitable radius around the symmetry axis.

The angle that the face plate first surface portion forms is that the surface rises towards the second surface portion connection is such that the air is entering at the bottom of the fireplace, being effected by the draft of the fire plum and the heat expansion it Encounters inside the air passage being heated by the combined effect of convection, conduction and radiation by the fire, the confining surfaces of the air passage creates a flow of preheated air towards the fire load being a combination of laminar and turbulent gas flow having a sufficient portion of the laminar flow so that the preheated air flowing past the first and second surface portion of the connection is able to partially travel a considerable horizontal distance. The turbulent portion of the flow is more prone to deflect upwards at said connection. The combined effect of the flow thus embodies a large area of the lower part of the fire load supported at least by the second surface portion of the face plate, the resulting buoyant flow covering a large area and reaching a great portion of the fire load surface area and the fire region. The confining surface of the fire load space defined by the second surface portion has an angle in relation to the supporting plan as to create a favorable chimney effect for the escaping gases to stabilize the flame with respect to the entraining air outside the Burner apparatus.

Further, the fire load space confining surfaces of the Burner apparatus according to the present invention may optionally be equipped with their inner surfaces with one or more spacing elements serving to create an air space between the surface and the fire load.

To achieve the favorable effect and advantage of the present invention compared to the prior art, the first and second angle may be defined according to the present invention, or may be varied based on empirical inspection or measurements and calculations evident for a person skilled in the art of arriving at an extension of the scope of the present invention.

The construction of the apparatus according to the present invention and said parts constituting said apparatus may be constructed by folding a continuous sheet or surface or attaching discontinuous parts by conventional means applicable to the utilized material, the material and the method of construction withstanding the elevated temperatures. of intended purpose of the apparatus as evident to a person skilled in the art.

Certain surfaces or constructions of the apparatus according to the present invention may be constructed of overlapping partial parts slidable over each other to accommodate one or more dimensions of the apparatus to adapt to fireplaces of different sizes or to accommodate insertion of said apparatus through a fireplace opening having a smaller dimension compared to a fire place space. Some structures or parts of the apparatus may also be constructed as foldable or detachable etc. to achieve the fitting or insertion of the apparatus in a fire place with different sizes or limited dimensioned openings.

The dimensions of the apparatus according to the present invention may be dimensioned according to the teachings of the present invention to yield the preferred effect. The effects of varying dimensions of the apparatus according to the present invention may be substantiated by visual inspection of such variables as flame color, flame stability, color of chimney gas, etc. or may be Verified by comparative measurements of gas temperatures in combustion chamber and chimney, concentration of partial gases in combustion gases, rate of heat release, etc. together with associated calculations as evident for a person skilled in the art, to arrive at the conclusion of the preferred arrangement in agreement with the present invention.

The objective of the invention is met by the features disclosed in the independent patent claim. A solid fuel burner apparatus according to the present invention is characterized by the features of the independent claim 1.

Some preferred embodiments of the invention are described in the dependent claims.

Short description of the drawings

Next, the invention is described in more detail with reference to the appended drawings, in which

Figure 1 illustrates a cross section of one apparatus according to the present invention.

Fig. 2 illustrates a cross section of one further embodiment of the apparatus according to the present invention.

Figure 3 is a detail drawing of one embodiment of the apparatus illustrated in Figure 1 according to the present invention.

Figure 4a is a detail drawing of one further embodiment of the apparatus illustrated in Figure 1 according to the present invention in a first functional state.

Figure 4b is a detail drawing of the embodiment illustrated in Figure 4a of the apparatus according to the present invention in a second functional state.

Figure 5 is a detail drawing of one embodiment of the apparatus illustrated in Figure 2 according to the present invention.

Figure 6 illustrates a cross section of one further embodiment of the apparatus according to the present invention.

Figure 7 is a detail drawing of one embodiment of the apparatus illustrated in Figure 6 according to the present invention.

A detailed description of the embodiments

Fig. 1 presents a cross section of one embodiment of the burner according to the present invention. The Burner is placed on a fire place bottom 10 having a grate for supplying air. The Burner has a face plate having a first surface portion 11 forming a first angle 12 in relation to the horizontal plane, the angle in this simply having a value of 22.2 degrees. Second surface portion 13, accomplished by folding, attaching etc. forms a second angle 14 in relation to the normal of the horizontal plane, the angle in this is substantially having a value of 36.2 degrees. According to the embodiment of Fig. 1, the Burner has optional spacing elements 15, made for an example of a flat bar, a round section, etc. to create and maintain an air space between face plate second surface portion 13 and fire load 18, comprised for example of split firewood.

In the embodiment of Fig. 1 of the present invention, the face plate first surface portion 11 and the fire place bottom 10 define an air passage cavity. The face plate second surface portion 13 and the rear wall 17 of the fireplace enclosure define a fire load space.

The thus formed cavity and space may be closed at their two vertical ends by an end plate 16 or by placing the Burner adjacent to the fire place enclosure walls to achieve the closing effect.

Fig. 2 presents a cross section of one further embodiment of the burner according to the present invention. The Burner is placed on a fire place bottom 20 having a grate for supplying air. The Burner has a face plate having a first surface portion 21 forming a first angle 22 in relation to the horizontal plane, the angle in which this is achieved having a value of 16 degrees. Second surface portion 23, accomplished by folding, attaching etc. forms a second angle 24 in relation to the normal of the horizontal plane, the angle in this is substantially having a value of 30 degrees. According to the embodiment of Fig. 2, the Burner has optional spacing elements 25a and 25b, made for example of a flat bar, round section, etc. to create and maintain an air space between face plate second surface portion 23 and firewood 28, and rear face surface 27b and firewood.

In the embodiment of Fig.2 of the present invention, the face plate base support structure 27a and the first surface portion 21 define an air passage cavity above the fire place bottom 20. The face plate second surface portion 23 and the rear face surface 27b of the Burner device define a fire load space closed at their two vertical ends by end plates 26 or by fire place enclosure walls.

Fig. 3 is a detail drawing of one embodiment according to the present invention and a cross sectional drawing of Fig. 1. The embodiment has a face plate with a first surface portion 31 and a second surface portion 33. The Burner is closed at its ends by opposite vertical end plates 36a and 36b. The drawings further show two spacing elements 35a and 35b made of L-section column attached to the surface 33. The burner may be placed adjacent to the fire place enclosure wall, for example the rear wall, thus forming the closing rear face surface of Burner and fire load space. The first and second Angles of the course are preferably 22.2 degrees and 36.2 degrees, respectively.

Figures 4a and 4b illustrate one further embodiment of the present invention, wherein the face plate of the burner having a first and a second surface portion is made of three parts 41a, 42a and 43a. Parts 41a and 42a are slidable relative to part 43 a having Slots 44a accepting fastening members 45 a for fastening and tightening parts 41a and 42a relative to 43a. Loosening of the fastening members allow for relative adjustment of the parts within the span and region determined by the dimensions of the slots. Fig. 4a shows the Burner retracted to possess a minimum width. Fig. 4b shows the burner extracted to its maximum width. Thus constructed, the embodiment of the present invention illustrated by Figures 4a and 4b has the further advantage that it can be adjusted to fire places of different sizes. Further, the Burner may also be inserted into the fire place having a small opening not accepting the Burner otherwise optimum in size for the fire place enclosure, by either retracting the Burner or taking the three parts Apart prior to insertion, to be assembled and extracted to the desired width inside the fire place. The first and second Angles of completion are preferably 10.1 degrees and 24.1 degrees, respectively.

Fig. 5 presents a detail drawing of one further embodiment of the burner according to the present invention. The Burner has a face plate having first surface portion 51 and a second surface portion 53, accomplished by folding, attaching etc. According to the embodiment of Fig. 5, the burner has optional spacing elements 55a and 55b attached to the surface 53. The burner is illustrated in the embodiment of Fig. 5 has a rear face surface composition of a lower part 57a of a solid metal sheet and an upper part 57b of a perforated metal sheet attaching to 57a. The first and second Angles of the course are preferably 22.2 degrees and 36.2 degrees, respectively.

Fig. 6 presents a cross section of one further embodiment of the burner according to the present invention. The Burner has a face plate having a first surface portion 61 forming a first angle 62 in relation to the horizontal plane. Second surface portion 63, accomplished by folding, attaching etc. forms a second angle 64 in relation to the normal of the horizontal plane. According to the embodiment of Fig. 6, the Burner has an optional spacing element 65 to create and maintain an air space between the Burner face plate and the fire load, such as for example wood pellets 68.

In the embodiment of Figure 6 of the present invention, the face plate first surface portion 61 defines an air passage cavity above a perforated bottom plate 60. The face plate second surface portion 63 and the rear face portion 67 of the Burner device define a fire load space.

The resulting cavity and space are closed at their two Imaginary horizontal ends by utilizing continuous surfaces for which the side edges meet to form an example of a rotationally symmetric face plate 71 and a rear face surface 77 as shown in Figure 7. The distancing element 75 is similarly constructed for example by bending a perforated sheet around a center axis distanced by a constant radius.

Although Fig. 7 shows a rotationally symmetric surface with a common axis of symmetry, the surfaces having an azimuthal projection of a sphere in the supporting plane, the Burner may be constructed according to the present invention to the shape of an ellipse, polygon, rectangle etc.

The scope of the invention is determined by the attached claims together with the equivalent claims. The skilled persons will again appreciate the fact that the expressly disclosed embodiments were constructed for illustrative purposes only, and the scope will cover further embodiments, combinations and equivalents that better suit each particular use of the invention.

Claims (10)

A solid fuel burner device comprising a front panel adapted to be disposed on the bottom of a fireplace (10, 20), the front panel having a first surface portion (11,21,31,41a, 42a, 43a, 41b, 42b, 43b, 51, 61) connected. a second surface portion (13, 23, 41a, 42a, 43a, 41b, 42b, 43b, 53, 63), said first surface portion (11, 21, 31, 41a, 42a, 43a, 41b, 42b, 43b, 51, 61) when determining the first angle (12, 22, 62) relative to the horizontal, said second surface portion (13, 23, 41a, 42a, 43a, 41b, 42b, 43b, 53, 63) determining the second angle (14, 24, 64) relative to the normal and, with said front panel supported on the bottom (10, 20) of the fireplace to retain said first angle (12, 22, 62) and second (14, 24, 64) angles, the first surface portion (11, 21, 31, 41a, 42a, 43a), 41b, 42b, 43b, 51, 61) forming an air cavity above the bottom (10, 20) of the fireplace and a second surface portion (13, 23, 41a, 42a, 43a, 41b, 42b, 43b, 53, 63) forming a fire load on the support ( 18, 28, 68), characterized in that said first angle (12, 22, 62) has a value between 10 and 35 degrees being the first surface portion (11, 21, 31, 41a, 42a, 43a, 41b, 42b, 43b, 51.61). ) ascending above the horizontal and towards the junction of the second surface portion (13, 23, 41a, 42a, 43a, 41b, 42b, 43b, 53, 63), said second angle (14, 24, 64) having a value of O and 45 degrees, an angle of deviation of the surface portion (13, 23, 41a, 42a, 43a, 41b, 42b, 43b, 53, 63) above the first surface portion (11, 21, 31, 41a, 42a, 43a, 41b, 42b, 43b, 51, 61), and and with said air cavity (18, 28, 68) and the fire load in contact with the bottom (10, 20) and the first (11, 21, 31, 41a, 42a, 43a, 41b, 42b, 43b, 51, 61) of the fireplace, and through an opening between the second (13, 23, 41a, 42a, 43a, 41b, 42b, 43b, 53, 63) surface portion of the joint. Device according to claim 1, characterized in that said front panel is formed of a rigid sheet material by bending the panel, joining the panels or any combination thereof. Device according to claim 1, characterized in that said first surface portion (11, 21, 31, 41a, 42a, 43a, 41b, 42b, 43b, 51, 61) and the second surface portion (13, 23, 41a, 42a), 43a, 41b, 42b, 43b, 53, 63) are planar surfaces or surfaces defined by vertical symmetry about the center line of a continuous or incremental rotation to form a surface of a front plate that joins the edges of its imaginary side to form a uniform surface of circular, elliptical, polygonal or Device according to claim 1, characterized in that said device further comprises one or two vertical side walls (16, 26, 36a, 36b, 56a, 56b) connected to the front panel. A device according to claim 1, characterized in that said device further comprises a bottom plate (60, 70) under the front plate, comprising one or more openings for air travel. Device according to claim 1, characterized in that said device further comprises a surface (17, 27b, 57a, 57b, 67, 77) of the rear part at a distance greater than zero relative to the first surface part and the second surface part and the joint of the first and second surface part. A device according to claim 1, characterized in that said device further comprises raised supports for supporting the front panel at the bottom of the fireplace to allow air to penetrate into said air cavity around the device substantially from the bottom of the fireplace. A device according to claim 1, characterized in that said device further comprises one or more distance-generating portions (15, 25a, 25b, 35a, 35b, 55a, 55b, 65, 75) for forming air channels in the fire load (18, 28, 68). and said front panel. A device according to claim 4, characterized in that said device further comprises one or more distance-generating members (15, 25a, 25b, 35a, 35b, 55a, 55b, 65, 75) for forming air ducts for the fire load (18, 28, 68). and at least one side wall (16, 26, 36a, 36b, 56a, 56b) of said one or two side walls (16, 26, 36a, 36b, 56a, 56b). Apparatus according to claim 6, characterized in that said apparatus further comprises one or more distance-generating portions (15, 25a, 25b, 35a, 35b, 55a, 55b, 65, 75) for forming air channels in the fire load (18, 28, 68). and between said rear surface (17, 27b, 57a, 57b, 67, 77).