FIREPLACE WITH HEAT-ACCUMULATING WALLS, COMPOSED OF SEPARATE, PREFABRICATED MODULE ELEMENTS

Abstract: A fireplace with heat-accumulating walls (2, 3, 4, 5) comprising a combustion chamber (10) and a flue gas space (14) being dismountably composed of separate, prefabricated module elements for walls (2, 3, 4, 5), top (7) and bottom (1), the wall elements (2, 3, 4, 5) consisting of an outer plate cover (28) formed as a mould, heat-accumulating material (29) being moulded therein and having assembly means (32) at its edge areas for dismountable mounting of the wall elements (2, 3, 4, 5).

Description: Fireplace with heat-accumulating trails, composed of separate, prefabricated module elements. The present invention relates to a fireplace with heat- accumulating walls comprising a combustion chamber and a flue gas space . Prior art Already in the 18th century it was known that stoves are a very efficient source of heat. A stove built in the con- ventional way has a very long life and practically no main¬ tenance is needed. Because of the rather complicated con¬ struction of stoves the building of a stove from bricks or other suitable stones is a very labour-intensive method demanding a very skilled builder in order to obtain a satis- factory result. Because of this, in the course of time stoves have become very expensive. Attempts have been made to make the erection of stoves easier by manufacturing them from prefabricated blocks. Such a stove construction is disclosed in SE-C-8102543-9. The above solution has been further developed by simpli¬ fying the manufacture and assembly of built fireplaces in general and especially stoves, so that they can be installed without need of the expert skill of a stove maker. Such a solution is described in SE-C-8702579-7. Here, the fireplace is made in to halves in a plant, preferably from blocks, whereupon the fireplace halves are transported to the place where they shall be assembled and installed. Since each fireplace half e.g. for building a stove normally weighs 800 - 1000 kgs, it has been regarded as practically impossible to bring such heavy elements into a dwelling and mount them ontop of each other. However, this problem has been solved by designing the stove with an integral stand for mounting of the lifting means. Many different kinds of fireplaces have been developed, and as examples of the different types existing on the market can be mentioned; different kinds of fire stoves, some with a sope-stone heat reservoir; inserts made of cast iron for open fireplaces. Common for all these alternatives is that they do not have the same efficiency and capacity as a stove and they also have other disadvantages such as short life, problems with cracks in the heat-reservoirs, they are heavy and cubersome, etc. The invention The object of the present invention is to provide a fireplace with heat-accumulating walls, which can be assembled easy and quickly in situ without any expert skills, which does not demand transportation and assembling of heavy and cumbersome elements, but still has heat-accumulating and heat-emitting properties which are close to those for a conventiona1 stove. Another object of the invention is to provide a fireplace which can be completely or partly dismantled and in which it is easy to replace defect parts without having to dismount the whole fireplace. A further object of the invention is to provide a fire¬ place which allows for optimization of the flue gas tempera¬ ture in the construction in which it shall be fitted. A further object of the invention is to provide a fire¬ place which can be used as fireplace when renovating stoves. These and other objects are attained with the above mentioned heat-accumulating fireplace which according to the invention is characterized in that it is dismountably com- posed of separate, prefabricated module elements for walls, top and bottom, the wall elements consisting of an outer plate cover formed as a mould, heat-accumulating material being cast therein and having assembly means at its edge areas for dismountable assembly of the wall elements. This embodiment makes possible an economical manufacture of the wall elements. Further, the flue gases will get into direct contact with heat-accumulating material facing inward¬ ly towards the flue gas space and thereby moisture can be both absorbed by and liberated from the accumulating material and the risk of cracking and erosion will therby be sub¬ stantially reduced in comparison with e.g. an embodiment with plate on both the inside and the outside of the wall ele¬ ments. Further, the fireplace can be transported in pieces being comparatively easy to handle and easy to assemble at the in¬ tended site as well as being dismounted completely or partly. The assembling time for the whole fireplace becomes very short. Further, the fireplace is well suited for being built-in in different ways and without problems it can be provided with water heating means and/or hot air circulation means. Further embodiments of the invention are disclosed in the subclaims. Short description of the drawings. Further objects, advantages and features of the invention will be evident from the following description of preferred embodiments of the invention shown on the accompanying drawings, on which fig. 1 is a schematic, exploded view of the mountable and dismountable fireplace, fig. 2 is a schematic view of the fireplace in mounted condition, fig. 3 is a vertical cross-section through the fireplace from the front side, fig. 4 is a vertical cross-sectional side view through the fireplace, fig. 5 is a horizontal cross-section through the firepla- ce, taken along the line A-A in fig. 3, fig. 6 is a top elevational view of the fireplace, fig. 7 is a schematic perspective view of the flue gas module, where non-visible parts are shown with dashed lines, and fig. 8 is a bottom insert in the combustion chamber. Description of preferred embodiments In fig. 1 the structure of the fireplace according to the invention is schematically shown, with separate modular elements in the form of a base element 1, side wall elements 2,3, backpiece 4, front piece 5, a modular insert 6 for the suspension of fireplace doors as well as a top element 7. In fig. 2 the parts are schematically shown, assembled to one unity 8. This construction of a fireplace is the result of a new way of thinking. Transportation of the separate elements is no problem and not the assemblage either, since the separate parts have a relatively low weight. Since the elements are self-supporting, which will be discussed more i detail below, the mounting will be simple, and it is also possible to dismount the fireplace, completely or partially. Fig. 3 is a vertical cross-sectional view, from the fron side of the fireplace. The fireplace rests in the base 1. Th side wall elements 2,3 and the back piece 40 are placed on the base, possibly with a sealing mass or other means for sealing purposes. The elements are mounted successively and are connected to each other by suitable jointings, e.g. by screwing, possibly with sealing means placed in-between. The top of the fireplace is formed by the top element 7 compris- ing a flue gas connector 8 and a slide valve 9 therefor. A combustion chamber 10 is contained in the lower part o the fireplace, the walls of which are covered with refractor material 11. In the embodiment shown the side wall elements comprise air ducts 12,13 for circulating air, whereby a direct heating of air is obtained. The fireplace can be combined with a fan for forced circulation. In the upper part of the fireplace a flue gas space 14 i arranged, which is separated from the combustion chamber 10. A suitable residence time and optimum transfer of heat from the flue gases to the heat-accumulating walls are attained with the aid of the flue gas module 15 arranged in the flue gas space. This module comprises a central flue element 16, the lower part of which expands like a funnel so that an intermediate bottom 17 is formed, which separates the two spaces of the fireplace from each other. A hub element 18 is arranged above this central flue element, in which the flue gas is forced to turn and flow downwards again and then to turn upwards to flow out through the flue gas connector 8 placed at the top. With this embodiment it is possible to adjust the length of the flue gas path through the flue gas space e.g. to adjust the fireplace to an actual chimney or corresponding means. In the embodiment shown, turbulators 19 are arranged on the outside of the hub element in order to further enhance the heat emission to the heat-accumulating wall elements surrounding the flue gas space. In the base element a primary air intake 20 is arranged for supply of combustion air at the bottom of the combustion chamber. A bottom insert 21 is arranged in the bottom of the fireplace with a central opening 22, preferably provided with a grid or fire bars. In the base element l secondary air channels 23 are also arranged, which lead to openings 24 in the restriction wall at the back of the combustion chamber. Fig. 4 is a vertical cross-sectional sideview, from which, besides what is shown in fig. 3, it can be seen that the flue gas module 15 is arranged out of contact of all walls of the flue gas space. Further, baffles 25 conducting the air which is intended to be directly heated, circulating in the side wall elements, are indicated with dashed lines. The flue gas module is laid up on brackets, preferably mounted with screws, at 27, in the side wall elements. With this a simple solution of the problem of inspection and any repair of the flue gas module without having to disassembly the complete fireplace, is attained. By removing the brackets 27 and letting the flue gas module down into the combustion chamber, it can then be dismounted and taken out through the door opening. Fig. 5 is a horizontal cross-sectional view through the fireplace taken along the line A-A in fig. 3. The wall elements are provided with a cover 28 of plate, pref. steel- plate with 3 mm thickness. Hereby the wall elements obtains the desired stiffness and will be self-supporting. The plate of the wall elements are bent into the formation of a rim with a height corresponding to the desired thickness of heat- accumulating material 29. The form of the bending is so adapted that double sealing surfaces 30,31 at an angle is achieved in the corners, whereby a very good seal can be obtained with simple means. The wall elements can be joined by direct screwing in the plate, as is illustrated with a screw 32 in fig. 5, or a reinforcement could be arranged e.g. in the form of a welded nut. Alternative solutions are of course possible without departing from the scope of the invention, i.e. that the fireplace shall be constructed from selfsupporting, prefabricated elements to be mounted in situ. By designing the wall elements with a plate cover, a number of advantages are obtained. The fireplace can be used just as it is, but is as well suitable for building-in, as desired. A major advantage is, however, that the plates act as remaining moulds and heat-accumulating mass is preferably moulded directly in the plates. After the curing of the cast compound the wall elements are ready to use. E.g. the proble of form stripping is completely eliminated. In order to reduce the risk of cracking in the heat-accumulating materia partition walls made of plate can be provided in the plate moulds in order to divide the heat-accumulating mass into several blocks (not shown in the drawings) . Fig. 6 is a top planar view of the top of the fireplace. In the embodiment shown, the top is intended to be filled with sand or similar material and can be complemented with a insulation of mineral wool or similar material, and comprise the flue gas connector 8 and the slide valve 9. The slide valve is manipulated with a control 33 accessible from the side of the fireplace. In fig. 7 the flue gas module 15 is shown in a perspec¬ tive view. The flue gas module comprises a central flue gas duct element 16 with a lower widened part with a bottom side edge corresponding to the cross section of the fireplace, arranged to act as a hanging floor or partition wall between combustion chamber and flue gas space. Soot-doors or inspec¬ tion doors 34 are preferably also arranged in this part, which when necessary also may act as by-pass conduit. From the combustion chamber 10 the flue gases are directed up through the central flue element up to the inside of the hub provided over it, and further on, as has be described in connection with fig. 3. In fig. 8 the bottom element 21 is shown in a larger scale with the central opening 23 for supply of primary air, as well as steps 35 at the upper edge for placing of refrac¬ tory material around the edges of the combustion chamber. The flue gas module is preferably manufactured from 3 mm plate. In the embodiment shown the hub has a pointed top, bu other embodiments are possible, e.g. semi-spherical, planar, substantially planar with rounded corners. In the figure a construction is shown which allows displacement of the two parts of the flue gas module in relation to each other in order to change the length of the flues, and thus a mechanic can adjust and optimize the function of the fireplace when connecting it to an existing chimney in an older building when the fireplace is mounted or at a later time. A suitable plate thickness in the module element is 3 mm, which results in a stable, self-supporting construction. A wall thickness of about 80 mm, i.e. 77 mm heat-accumulating material, is suitable. Thanks to the design of the fireplace it can be mounted in practically all spaces without any specific limitations. Then it can be used as such or be built in with bricks or in any other way, e.g. into an old stove, which then will have a modern interior and which meets all possible requirements of the authorities. Further, the fireplace may be complemented with a water heater, fans for air heating by addition of, or building-in conventional equipment. Thus, with the fireplace according to the invention a flexible, easily adaptable heat source is obtained which replaces practically all variations of stoves, pot stone fireplaces etc. existing on the market.

Claims: Claims 1. A fireplace with heat-accumulating walls comprising a combustion chamber and a flue gas space, characterized in that it is dismountably composed of separate, prefabricated module elements for walls, top and bottom, the wall elements consisting of an outer plate cover formed as a mould, heat- accumulating material being moulded therein and having assembly means at its edge areas for dismountable assembly of the wall elements. 2. A fireplace according to claim 1, characterized in that the wall module elements comprise side wall elements, which, in the part adjacent to the combustion chamber have channels for air circulation. 3. A fireplace according to claims 1-2, characterized in that a flue gas module made of plate is provided in the flue gas space. 4. A fireplace according to claim 3, characterized in that the flue gas module comprises a central flue element connected to the combustion chamber and a hub element surrounding said flue element and having walls overlapping the walls of the central flue element. 5. A fireplace according to claim 3, characterized in that the flue gas module has a lower bottom plate with a form corresponding to the inner cross section of the fireplace and forming a partition wall between the combustion chamber and the flue gas space, that said bottom plate is mounted on removable brackets, and in that the flue gas module is constructed to be divisible, whereby the parts separately can be let down into the combustion chamber and be picked out through an entrance opening of the combustion chamber. 6. A fireplace according to claim 4, characterized in that turbulence forming baffles are arranged on the outside of the hub element. 7. Fireplace according to claim 1 - 6, characterized in that the bottom plate is removably arranged at the bottom of the combustion chamber in order to simplify dismounting and mounting of the flue gas module without dismounting the whole fireplace.

Inventors: HANSSON KENNETH, HANSSON, KENNETH
Applicants: CRONSPISEN KAKELUGNAR AB, HANSSON KENNETH, HANSSON, KENNETH
Application year: 1995
Main classification: F24B1
IPC codes: F24B1