WO2007125211A1

WO2007125211A1 - Enclosed fireplace with improved combustion and increased operating temperature

Info

Publication number: WO2007125211A1
Application number: PCT/FR2007/000731
Authority: WO
Inventors: Frédéric HAAS; Marc Boulanger
Original assignee: Fondis
Priority date: 2006-04-28
Filing date: 2007-04-27
Publication date: 2007-11-08
Also published as: DE602007009512D1; FR2900461B1; WO2007125211B1; EP2013541B1; FR2900461A1; ATE483141T1; EP2013541A1

Abstract

The enclosed fireplace is notable in that it has a rear air inlet, and a fireplace the base and side walls of which are lined with refractory blocks (7), (9) and (5), (6), a primary air circuit formed of two symmetric branches, each one opening through a side refractory block (5) or (6) via ports (38) situated above the base plane of the fireplace (1) and a secondary air circuit formed of two symmetric parts grafted onto the primary air circuit and running along the side refractory blocks (5) and (6) to end at a distributor despatching the heated air in a downwards stream against the rear face of the glazed part (3) via a curved deflector (36). The fireplace is lined with refractory blocks and thermally insulated. This invention is of interest to the manufacturers of enclosed fireplaces.

Description

Closed fireplace with improved combustion and increased operating temperature.

The present invention relates to a fireplace closed combustion improved including wood and increased temperature.

It also relates to improved primary and secondary air supply circuits and thermal insulation and thermal inertia in the case of a closed fireplace including wood with at least one transparent wall of flame vision.

With standards becoming more stringent, a chimney must have the maximum thermal efficiency and the cleanest possible combustion, that is, it must reject only small amounts of volatile or particulate pollutants. microscopic solids for a better ecology.

The air supply of a closed fireplace and its operating temperature are decisive factors for the quality of combustion and therefore the cleanliness of the fireplace.

The main purpose of the invention is to substantially increase the operating temperature of the furnace while keeping it as long as possible in order to obtain a better combustion, a pyrolytic elimination of the maximum of ¹ unburned and of products staining the interior of the furnace. fireplace, especially the inside of the glass door. Another object of the invention is to increase the speed of the outlet airflow, thus removing more quickly and more volatile materials which may dirty the inside of the hearth and the rear face of the glazed door.

The invention also aims to provide an improved primary and secondary air supply circuit for a closed fireplace contributing fireplace better combustion and cleanliness of the fireplace.

Noting that the improvement of the central air intake by the ashtray provides only a limited improvement, the inventors have designed a side system for supplying primary combustion air, passing through each time a refractory block and opening by means of orifices located on each side of the hearth approximately level with the fire. By the joint use of refractory blocks that accumulate the heat side fireplace and sufficient thermal insulation against the metal wall of the body of the device, the focus focuses and keeps its temperature longer. This higher temperature results in better combustion during operation and is still maintained at reduced speed and a significant reduction in pollutant emission rates even at the reduced operating speeds of the closed fireplace.

Similarly, for better economy, 1 'air supply is through the back of the chimney, which allows to connect directly to the outside. By heating the air by the primary and secondary air circuit against various surfaces including those of the refractory blocks, the combustion is improved for better thermal performance and a good temperature regularity in the room. The invention also relates to a secondary air circuit which starts from the air inlet and extends upwards along the bottom and side refractory blocks to give rise to a heated air flow which is projected. in a descending layer against the rear face of the glass wall of the chimney door to ensure cleanliness, on the one hand by removing the dirty particles by the force of the air flow, and on the other hand by burning those arriving nearby by the high temperature of the air flow and its oxygen richness. Other features and advantages of the invention will appear on reading the detailed description which follows, description made with reference to the accompanying drawings, in which:

. Figure 1 is a general perspective view of a closed fireplace according to the invention;

. FIG. 2 is a general perspective view of the front of a closed hearth chimney according to the invention, the lateral part of the body of the chimney being shown partially cut away and transparent for the thermal insulation plate and the cladding of the sidewall, the air flows being represented by arrows;

. Figure 3 is a general perspective view, similar to that of Figure 2, of the front of a closed fireplace according to the invention, wherein the upper part of the door and its frame was also partially removed;

. FIG. 4 is a general perspective view of the rear of a closed hearth chimney according to the invention, the rear and side portion of the body of the chimney being partially shown in cutaway and transparent for the thermal insulation plate; and the dressing of the side and the back; . Figure 5 is a schematic sectional view taken horizontally through the fireplace of a closed fireplace according to the invention.

In the remainder of this description, by chimney, we will hear any type of solid fuel heater, closed by a transparent door allowing the vision of the flames. The present invention relates to

1 improvement of combustion including wood and the operating temperature of the fireplace and the insulation and thermal inertia of a closed hearth with transparent door.

It also relates to a primary air and secondary air circuit designed to improve combustion and to ensure the cleanliness of the glass regardless of the appearance of the fire. On a solid-fuel burning appliance, in particular with wood, for example a closed hearth with a metal body 1 taken by way of example, with a front door 2 having a curved or multifaceted glass surface 3, and an interior fireplace 4, a total interior lining is provided, but at least lateral to the hearth and bottom of hearth in the form of refractory blocks. There are thus lateral blocks 5 and 6 and base blocks including a central block 7 bottomed bottom 8 and peripheral blocks such as 9 and a special front block 10 shaped fender 11 constituting the front stop for the logs of wood .

The refractory blocks have a density and a thickness adapted to act as a heat accumulator having an effective thermal inertia to ensure a certain thermal relay between the different heating stages.

To improve the thermal performance, and in particular to increase the operating temperature of the hearth, thermal insulating plates 12 and 13 of sufficient thickness, dress the inside or outside face of at least each of the side walls of the hearth body and it is possible to optionally provide a cast iron plate that occupies at least a portion of the rear wall of the fireplace. This cast iron plate acts as a steering wheel additional thermal acting in conjunction with the refractory blocks.

Various other means of thermal insulation of the hearth are possible such as sandwich structures, hollow structures in which heated air passes or other. The general purpose is to limit thermal losses by radiation from the walls of the body of the home.

Thus, a special thermally insulating glass single or double glazed glass can be used for the glass door.

These means are to keep the heat of the home for as long as possible when it runs at reduced speed or when it goes out.

The fireplace comprises a circuit 14 for supplying primary and secondary air. This circuit has a single input 15 at the rear of the apparatus formed of a junction box 16 to an air intake duct, the box covering an air intake opening 17 with an adjustable flow rate, for example under the shape of a pivoting flap 18 controlled by a handle or an operating lever 19 outside the device connected by linkage to the pivoting flap 18.

The air inlet opening 17 is located approximately in the middle position at the rear of the hearth. It opens onto a channel 20 along the rear of the hearth which forms two branches 21 and 22 each going to one of the rear corners 23 and 24 of the hearth 4.

At this level, the airflow is divided on each side of the hearth into two branches: a branch of secondary air 25 and 26 along the vertical rear edge of the hearth and a horizontal branch of primary air 27 and 28 respectively following each lateral side of the fireplace under the corresponding lateral refractory block.

The secondary air circuit is formed of two symmetrical parts joining in the upper part of the glass wall.

Each lateral refractory block 5, 6 has a parallelepipedal overall shape with an oblique cutaway 29 and 30 with a rear edge each forming, when the lateral block is in place, with the dressed side wall of the thermal insulation plate 12 or 13 and the back plate of the hearth body, the two joining at the rear edge, a rising channel 31 or 32 of triangular section forming each rising branch 25 or 26 along which the secondary air travels to the upper part of the hearth .

The secondary air path continues forward on each side by an upper transverse channel such as 33 running along the top of each refractory block transversely and at the edge of the hearth.

The upper transverse channels 33 extending each ascending branch 25 or 26 of the secondary air circuit open at the ends of a distributor 34 whose shape follows at a distance the contour of the upper part 35 of the glass part 3 to create at this level a descending air curtain preferably guided by means of a curvilinear baffle 36 inclined downwards (Figure 3). This air curtain provides a hot air flow in a down ply to ensure the cleanliness of the glass by removing the messy particles that could stick on the rear face of the glass and burning those of them. The primary air arrives at the rear of the side refractory blocks 5 and 6 after preheating the along the edge of the base of the hearth itself filled with refractory blocks 7 and 9. These have at a certain height from the base plane of the hearth and for example approximately at the level of the fire, a group 37 orifices such as primary air inlet furnace gui individually communicate with outlet openings of the side channel by recesses such as 39 dug in the rear face of each side block 5 and 6. The primary air is thus still heated in contact with each refractory block before leaving it in the firebox.

Therefore, the air circuits described above, by the location of their outlets and the reheating of the air they allow, contribute to ensure perfect cleanliness of the rear face of the glass wall of the chimney and excellent combustion of solid fuel, for example wood, which provides energy saving and reduced emission of pollutants. Other embodiments may be envisaged by those skilled in the art without departing from the general principle of the invention.

Claims

An improved combustion chimney fireplace with an increased operating temperature comprising an internal combustion chamber (4), at least one glass viewing part (3), a primary air circuit and a secondary air circuit of combustion and cleanliness of the glass wall characterized by:

. an air inlet (15) with adjustable flow rate located at the rear of the inner firebox (4),

. an inner hearth (4) with a base plane and side walls filled with refractory blocks by bottom hearth blocks (7) and (9) and side blocks (5) and (6),. thermal insulation at least around the fireplace

. a primary air circuit formed of two branches along the refractory blocks of the bottom of the hearth

(7) and (9) and lateral (5) and (6) each exiting inside the focus through a refractory side block (5) or (6) through orifices (38) located above the bottom of the fireplace

. a secondary air circuit which starts from the air inlet (15), runs along the refractory bottom blocks (9) and (7) and extends upwards along the lateral refractory blocks (5) and (6) to give rise to a downward flow of air along the rear face of the glazed portion (3) forming a hot air insulation curtain to protect the rear face and burn materials that may contaminate the window.

2. closed fireplace according to claim 1 characterized in that the secondary air circuit is grafted on the primary air circuit, the first branches from the rear air inlet (15) being common.

3. Fireplace closed fireplace according to claim 1 characterized in that the rear air inlet (15) is in the middle position in the lower part at the rear of the hearth.

4. fireplace closed hearth according to claim 1 characterized in that the two branches of the primary circuit from the rear air inlet (15), along the lower rear edges of the inner hearth (4) and the side edges of the hearth and are each connected by several outlets, to corresponding vertical longitudinal recesses (39) recessed in each refractory side block (5) or (6) to, after passing through the corresponding refractory block, lead into the inner fire (4) at the exit of each recess (39) through an orifice (38) at a height greater than the level of refractory blocks lining the bottom of the hearth.

5. fireplace closed fireplace according to the preceding claim characterized in that the orifices (38) of the primary air outlet in the home are located substantially at the level of the fire.

6. closed hearth according to claim 4 characterized in that each of the two branches of the primary air circuit runs along the edges of the refractory bottom hearth (7) and (9) and lateral (5) and (6) for terminate in and through the corresponding lateral refractory block (5) or (6).

7. closed hearth according to any one of the preceding claims characterized in that the secondary air circuit is formed of two symmetrical parts and is composed on each side of a lower branch common with that of the primary air circuit between l the air inlet (15) and the corresponding lower corner (23) or (24) of the furnace body containing the focus, a rising branch respectively (25) or (26) along each edge rear, upper branch horizontal (27) or (28) along the upper edge of the hearth, the two symmetrical parts meeting above the upper edge of the glass wall (3) to form a common air distribution ramp in view the creation of a descending sheet of hot air for the cleanliness of its rear face.

8. Closed hearth according to the preceding claim characterized in that the branches of the secondary air circuit along the edges of the refractory blocks (9) and (7), the rear vertical edge of each refractory side block (5) or (6). constituting one of the side walls of each rising branch (25) or (26) of the secondary air circuit.

9. closed hearth according to claim 7 characterized in that the common rail is of curvilinear shape slightly distant from the upper edge of the glass portion (3) and opens on the entire upper inner edge of the glazed portion (3).

10. Closed hearth according to the preceding claim characterized in that the common rail is extended downwardly by a downward inclined curved deflector (36).

11. closed hearth according to claim 1 characterized in that each side wall of the closed hearth (1) is lined by a thermal insulation plate (12) or (13) in contact or not with the rear face of the corresponding side refractory block .

12. Closed hearth according to claim 1 characterized in that all the walls of the fireplace are lined with thermal insulation.

13. Closed hearth according to claim 1 characterized in that the glass of the glass door is thermally insulating glass.

14. Closed hearth according to claim 1 characterized in that the glass of the glass door is double glazed.