WO2009136180A1

WO2009136180A1 - Fireplace

Info

Publication number: WO2009136180A1
Application number: PCT/GB2009/050315
Authority: WO
Inventors: Michael Aherne
Original assignee: Michael Aherne
Priority date: 2008-04-29
Filing date: 2009-03-31
Publication date: 2009-11-12
Also published as: GB0807760D0; GB2459834A

Abstract

An outdoor fireplace (10) comprising a combustion chamber (16) defined by an outer wall (14) enclosing, at least partially, the combustion chamber (16), wherein the fireplace (10) further comprises a screen (18) positioned within the outer wall (14) between the interior of the combustion chamber (16) and the outer wall (14), such that a gap is formed between the screen (18) and the outer wall (14) to provide an insulating region.

Description

FIREPLACE

Field of the Invention

This invention relates to a fireplace, in particular an outdoor fireplace.

Background to the Invention

A fireplace construction that has previously been proposed includes a combustion chamber defined by an upwardly extending mesh wall. Such a construction is known as a brazier. A disadvantage of a mesh wall is that the heat escapes in all directions and is not focussed on the user. Furthermore, the mesh is constructed from metal and becomes very hot and subsequently may cause burns should people or animals touch it.

A further disadvantage of such constructions is that the waste, such as ash, and burnt fuel is collected in the combustion chamber itself. Therefore, when the waste and burnt fuel requires removing, the whole assembly must be dismantled. This is inconvenient and time consuming.

Many barbeques are not suitable for use as outdoor fireplaces due to the temperatures experienced by the combustion chamber. Furthermore, barbeques become very hot during use and may cause burns to people and animals should they touch the barbeque during or shortly after use. Similarly, many outdoor fireplaces are not suitable for use as barbeques due to the shape of the outdoor fireplace being unsuitable for putting a grill above the heat source. Furthermore, outdoor fireplaces are difficult to control as the ventilation to the flames is often predetermined and the inability to control the ventilation may lead to badly-cooked food.

The present invention, at least in its preferred embodiments, seeks to obviate one or more of these disadvantages.

Summary of the Invention Accordingly, the present invention is directed to an outdoor fireplace comprising a combustion chamber defined by an outer wall enclosing, at least partially, the combustion chamber, wherein the fireplace further comprises a screen positioned within the outer wall between the interior of the combustion chamber and the outer wall, such that a gap is formed between the screen and the outer wall to provide an insulating region. The gap created between the screen and the outer wall creates an air space, which acts as a good insulator. The outer wall is not exposed to the degree of heat that it would be without the screen in place and so the outer wall remains relatively cool compared to the screen and the fire. This widens the range of possible materials from which the outer wall may be constructed and also increases the potential lifetime of the outer wall.

Preferably, the screen comprises a reflective material to reflect heat produced by burning fuel. The reflective material directs the heat away from the outer wall, further reducing the likelihood of the outer wall becoming relatively hot to the touch. Thus, the screen may be formed of metal, in particular sheet metal. It is advantageous if the screen comprises stainless steel, which is a relatively good thermal insulator.

Advantageously, the fireplace further comprises a fuel grill positioned within the combustion chamber to allow air to flow below and around the fuel grill. By having a fuel grill within the combustion chamber, the air can circulate around the fuel and this allows for more complete combustion of the fuel.

The outer wall and the screen may define an opening in the combustion chamber to allow heat from burning fuel to be directed in an outward direction from the fireplace. The opening, at an intended front region of the outdoor fireplace, allows heat to be directed out of the combustion chamber. The screen can be shaped to focus the heat from within the fireplace toward the opening. This has the result that instead of radiating heat in all directions, the heat is radiated through the opening to provide a more efficient heater.

In a preferred embodiment, the combustion chamber further comprises a removable collection tray below the fuel grill, aligned to collect waste materials. The removable tray, or drawer, allows for the ashes and any other waste, such as burnt fuel, to be removed from the bottom of the combustion chamber, without requiring any heavy lifting OT complex cleaning. A further purpose of the removable tray is to allow the amount of air flowing below the fuel grill to be adjusted. Thus, the tray may be slidably received within the fireplace. The tray may be slid into a partially opened or closed position, according to the air flow required. This allows a degree of control over the rate of fuel combustion and therefore the temperature of the fire within the combustion chamber.

In a preferred construction, the outer wall comprises foamed concrete. Foamed concrete is a relatively good insulator due to the relatively high air content compared to other types of concrete. Furthermore, foamed concrete exhibits stable load bearing capacity during and after exposure to fire. Therefore, the outer wall will maintain its structural integrity and also is in itself a good insulator, further decreasing the likelihood of the wall becoming hot enough to burn a person or animal.

Advantageously, the outer surface of the foamed concrete outer wall is closed-cell foamed concrete. Closed cell foamed concrete, that is foamed concrete wherein all of the air spaces are close cells, is more resistant to weathering and to frost damage.

Preferably, the foamed concrete comprises fly ash. Fly ash is a readily available byproduct from power generation and is relatively cheap, whilst also being light-weight.

It is advantageous if the outer wall is skimmed with ceramic material to provide additional protection from weathering.

Advantageously, the outer wall may be formed by moulding. In particular, the outer wall may be formed as a one-piece moulding. This provides a particularly efficient method of manufacture. The material of the moulded outer wall may be concrete, in particular foamed concrete, as described above. The outer wall of the combustion chamber may provide the entire outer surface of the fireplace.

It is preferable that the screen is provided with grill holding formations. The fireplace may be used for cooking food by providing means for holding a grill above the fire. In one construction, the grill holding means comprise at least one aperture to receive a protrusion from the grill. Alternatively, the grill holding means comprise at least one protrusion on which the grill may be positioned.

The fireplace may be a free-standing fireplace. Furthermore, the fireplace may be portable, in the sense that it may be used in alternative locations, rather than being installed in a single location.

The fireplace, the outer wall and/or the combustion chamber may have a generally circular cross-section, as this provides for an aesthetically-pleasing design. However, other cross-sectional shapes, such as elliptical, square or rectangular, are possible.

Brief Description of the Drawings

An embodiment of the invention will now be described, by way of example only, and with reference to the accompanying drawings, in which: Figure 1 is a cross-sectional side view of an embodiment of an outdoor fireplace in accordance with the present invention;

Figure 2 is a front view of the outdoor fireplace shown in Figure 1 ;

Figure 3 is a side view of the outdoor fireplace shown in Figure 1 ;

Figure 4 is a top view of the outdoor fireplace shown in Figure 1 ; and Figure 5 is a perspective view of the outdoor fireplace shown in Figure 1.

Detailed Description of Exemplary Embodiments

Figures 1 to 5 show an outdoor fireplace 10 comprising a moulded foamed concrete crucible 12, defined by an outer wall 14, which at least partially encloses a combustion chamber 16. A stainless steel screen 18 is provided within, and in close proximity to, the outer wall 14, between the interior of the combustion chamber 16 and the outer wall 14, and the screen 18 generally follows the shape of the outer wall 14, such that an air-space is provided between the screen 18 and the outer wall 14.

At a position within the combustion chamber 16 is a fuel grill 20, comprising a plurality of slits to allow ash and waste material to fall through the grill 20. Directly below the fuel grill 20 is a collection tray 22, within a recess of the crucible 12, such that waste from the fuel grill 20 is collected in the collection tray 22. The outer wall 14 and the screen 18 have a corresponding U-shaped opening 26 at the intended front of the fireplace 10, allowing access to the inside of the crucible 12 radially, through the outer wall 14.

The screen 18 is provided with apertures 28 to receive a protrusion of a cooking grill 30. A front fire grate 32 is provided at the bottom end of the U-shaped opening 26, extending in an upward direction. The fire grate 32 prevents the lighted fuel from falling through the opening 26.

Fuel is placed on the fuel grill 20 and lit. Smoke and other combustion fumes pass through the top of the crucible 12, whilst at least some of the heat and light provided by the combusting fuel is reflected by the screen 18 and passes through opening 26. Any ash that is formed during combustion of the fuel can pass through the slits in the fuel tray 20 and enters the collection tray 22.

The collection tray 22 can be opened or closed according to the amount of airflow that is required. When the tray 22 is in a fully closed position, the airflow to the combustion grill is restricted. As the tray 22 is pulled out, the airflow increases.

Numerous other variations and modifications to the illustrated construction may occur to the reader familiar with the art without taking the device outside the scope of the present invention. For example, castors or wheels may be applied to the base of the crucible 12 to allow it to be moved easily. Additionally, a removable lid may be provided to protect the outdoor fireplace while it is not in use.

In summary, an outdoor fireplace comprising a combustion chamber defined by an outer wall enclosing, at least partially, the combustion chamber, wherein the fireplace further comprises a screen positioned within the outer wall between the interior of the combustion chamber and the outer wall, such that a gap is formed between the screen and the outer wall to provide an insulating region.

Claims

1. An outdoor fireplace comprising a combustion chamber defined by an outer wall enclosing, at least partially, the combustion chamber, wherein the fireplace further comprises a screen positioned within the outer wall between the interior of the combustion chamber and the outer wall, such that a gap is formed between the screen and the outer wall to provide an insulating region.

2. A fireplace according to claim 1, wherein, the screen comprises a reflective material to reflect heat produced by burning fuel.

3. A fireplace according to claim 2, wherein the screen comprises stainless steel.

4. A fireplace according to any preceding claim, wherein the outer wall and the screen define an opening in the combustion chamber to allow heat from burning fuel to be directed in an outward direction from the fireplace.

5. A fireplace according to any preceding claim, further comprising a fuel grill positioned within the combustion chamber to allow air to flow below and around the fuel grill.

6. A fireplace according to claim 5, comprising a removable collection tray below the fuel grill, aligned to collect waste materials.

7. A fireplace according to any preceding claim, wherein the outer wall is formed from foamed concrete.

8. A fireplace according to claim 7, wherein, the outer surface of the foamed concrete outer wall is closed-cell foamed concrete.

9. A fireplace according to claim 7 or claim 8, wherein, the foamed concrete comprises fly ash.

10. A fireplace according to claim any one of claims 7 to 9, wherein the outer wall is skimmed with ceramic material, at least on its outside surface, to provide additional protection from weathering.

11. A fireplace according to any preceding claim, wherein the screen is provided with grill-holding formations.

12. A fireplace according to claim 11, wherein, the grill-holding formations comprise at least one aperture to receive a protrusion from a grill.

13. A fireplace according to claim 11, wherein the grill holding formations comprise at least one protrusion on which the grill may be positioned.