GB1583126A - Fireplace installation - Google Patents

Description

(54) A FIREPLACE INSTALLATION (71) We, SUPERPART AG, a Swiss joint-stock company, of 8 Ryffligässchen, CH-3011 Berne, Switzerland, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement :: A fireplace installation for heating a room comprises according to the present invention a hearth, two side members flanking said hearth, a flue hood supported by said side members and a double-walled metal insert surrounding said hearth from three sides within said side members and acting as a heat reflector, said insert being divided by partitions into a rear chamber and two side chambers, an air inlet being provided at the top of said rear chamber and an air passage being provided near the bottom of each partition leading from said rear chamber into each side chamber, an outlet being provided near the top of each side chamber leading through an aligned outlet in the associated side member.

Preferably a second outlet is provided near the bottom of each side chamber aligned with an obliquely rising outlet in the associated side member issuing heated air into the room to be heated.

Preferably also a thermal insulation is provided between the outer faces of said metal insert and said side members, and also dampers are provided for the control of the air flow into said rear chamber and out of said side chambers.

With most known fireplaces the fresh air introduced from outside the room is led only through passages directed upwards, and thus follows the natural thermal convection circulation. Poor heating of the fresh air is thus obtained before it is discharged into the room.

In order to increase the heating of the fresh air it is known to let the air pass through an air channel system arranged in the walls surrounding the hearth and comprising a downflow duct whose air intake is located higher than its outlet. As the flow of air in the downflow duct takes place downwards from the top, i.e. in a direction opposite to natural thermal convection circulation, a heavy turbulance is generated and intense heating of the air takes place. To generate a flow of air directed downwards in the downflow duct a low pressure in the room is required. If the windows and doors thereof are closed and made draughtproof, a low pressure is created in the room to be heated as a consequence of the combustion gases flowing out.However, if the room is not tightly sealed a low pressure for aspirating air through the downflow duct will not be generated, but, instead, cold air will be aspirated through open windows and doors or through cracks or other leaks. The advantages of the hearths referred to are thus wasted.

In order to obviate this disadvantage, it is known to arrange at the outlet of the downdraught duct an up-draught passage which opens into the room to be heated. This passage is capable of generating a low pressure at the bottom end of the downflow duct and thereby drawing an air stream into the room, and consequently the flow of the air in the passages is no longer dependent on the low pressure in the room to be heated. In this kind of known fire places each updraught passage is arranged in the side walls of the hearth. These side walls are part of the support structure for the smoke duct opening into the associated chimney. The load supporting capacity of this structure is reduced owing to the channels arranged therein.Moreover these side wall elements are made of ceramic material, concrete or rock which takes some time to warm up sufficiently before transmitting heat to the air in the updraught passage to make the air rise therein and to accelerate the air flow into the room.

The object of the present invention is to provide a fireplace having the advantages of the known fire place described hereinabove while avoding the disadvantages of the reduced load carrying capacity of the side wall elements. Moreover, according to the present invention the walls of the updraught passage are heated quickly so that the air in this passage is heated quickly and a draught is created in the air passage system.

The invention will now be described in more detail with reference to an embodiment illustrated by way of example in the accompanying drawings, in which: Fig. 1 is an exploded perspective view of a fire place according to the invention.

Fig. 2 is a sectional frontal elevation thereof, Fig. 3 is a sectional side elevation thereof, Fig. 4 is a plan view in section on line IV-IV of Fig. 2, and Fig. 5 is a perspective view of the metal insert according to the invention.

The fire place illustrated comprises a base plate 1, a bottom plate 2, two side elements 3 and 4, a top plate 5 and a hood 6 arranged on top of the latter. These parts 1--6 form the structural support of a flue (not shown).

The fire place has also fire stops 7 and 8 and is lined inside on three sides by a metal insert 9 designed as a reflector.

The metal insert 9 is double-walled and comprises a back portion 10 and two side portions 11 and 12. Partition walls 13 and 14 are arranged between the back portion 10 and the side portions 11 and 12, dividing the insert 9 into three chambers: one in the back portion 10, and one in each side portion 11, 12. Heat insulations are arranged to separate the portions 10, 11, 12 of the insert 9 from the side elements 3, 4.

The back portion 10 is provided at the top with an air intake 18 from where aspirated fresh air is directed to flow downwards through the chamber of the back portion 10 designed as a downflow duct. The air is heated therein intensely owing to turbulence generated by resistence to the descending flow. Near the lower end of each of the partition walls 13, 14 a couple of air inlets 19, 20 and 21, 22, respectively (Fig. 2) are arranged. From the upper inlets 19 and 21 the air flows into the room to be heated in the direction of the arrow 'A' (Figs. 1 and 5), flowing through passages 23 and 24 and through lower outlets 25, 26, respectively, in the side members 3 and 4. As shown in Fig. 2, the outlets of the passages 25, 26 are located higher than their inlets. Consequently a rising flow of hot air is generated in the outlet passages 25, 26 creating a pressure drop in the passages 23, 24.

From the lower air inlets 20, 22 the air flows in the direction of arrow 'B', i.e. below and past the passages 23, 24, respectively, and into the chambers of the side portions 11, 12 of the insert 9. At the upper part of said chambers there are arranged upper outlet passages 27, 28 extending through the structural side members 3, 4 respectively, into the room to be heated. A considerable pressure drop is thus created in the lower part of the chambers in the side portions 11, 12 of the insert 9 owing to the rising flow of hot air. The heat energy derived from the side portions of the metal insert is utilised for heating the air rising in the chambers of the side portions 11, 12.

In the lower outlet passages 25, 26 there are arranged air control dampers 29, 30, and in the upper outlets 27, 28 there are provided air control dampers 31, 32 (Fig. 2) to control the hot air flowing out through those outlet passages. Thus the fire place according to this invention allows various operations: it can create intense heat emission at low pressure in the room to be heated, sending an air flow through the lower outlet passages 25, 26 into that room. Alternatively it can send hot air through the upper outlet passages 27, 28 into that room even when the pressure therein is not low enough for the operation mentioned above. As all the outlets into the room are situated higher than the air inlets 19, 20 and 21, 22 of the side portions 11, 12 of the insert 9, heated air can rise by natural convection circulation even when the pressure is not low enough in the room to be heated.This natural circulation causes air to flow down in the back portion 10 of the insert 9.

As can be seen from Fig. 1, two air control passages 33, 34 are formed when placing the bottom plate 2 upon the base plate 1. Through these passages fresh air is led directly to the fire, flowing from both sides immediately under the hearths 7, 8. These hearths are strongly heated by the fuel burning on them, and consequently the aspirated air is heated before it reaches the combustion chamber.

The amount of this primary air can be metered or throttled as desired by means of draught dampers 35 and 37. The flow of heated air to the room can be metered or throttled as desired by means of draught dampers 36 (Figs. 3, 4) and 360 (Fig. 3).

WHAT WE CLAIM IS:- 1. A fire place installation for heating a room comprising a hearth, two side members flanking said hearth, a flue hood supported by said side members, and a double-walled metal insert surrounding said hearth from three sides within said side members and acting as a heat reflector, said insert being divided by partitions into a rear chamber and two side chambers, an air inlet being provided at the top of said rear chamber and an air passage being provided near the bottom of each partition leading from said rear chamber into each side chamber, an outlet being provided near the top of each side chamber leading through an aligned outlet in the associated side member.

2. A fire place installation according to claim 1, wherein a second outlet is provided.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. invention the walls of the updraught passage are heated quickly so that the air in this passage is heated quickly and a draught is created in the air passage system. The invention will now be described in more detail with reference to an embodiment illustrated by way of example in the accompanying drawings, in which: Fig. 1 is an exploded perspective view of a fire place according to the invention. Fig. 2 is a sectional frontal elevation thereof, Fig. 3 is a sectional side elevation thereof, Fig. 4 is a plan view in section on line IV-IV of Fig. 2, and Fig. 5 is a perspective view of the metal insert according to the invention. The fire place illustrated comprises a base plate 1, a bottom plate 2, two side elements 3 and 4, a top plate 5 and a hood 6 arranged on top of the latter. These parts 1--6 form the structural support of a flue (not shown). The fire place has also fire stops 7 and 8 and is lined inside on three sides by a metal insert 9 designed as a reflector. The metal insert 9 is double-walled and comprises a back portion 10 and two side portions 11 and 12. Partition walls 13 and 14 are arranged between the back portion 10 and the side portions 11 and 12, dividing the insert 9 into three chambers: one in the back portion 10, and one in each side portion 11, 12. Heat insulations are arranged to separate the portions 10, 11, 12 of the insert 9 from the side elements 3, 4. The back portion 10 is provided at the top with an air intake 18 from where aspirated fresh air is directed to flow downwards through the chamber of the back portion 10 designed as a downflow duct. The air is heated therein intensely owing to turbulence generated by resistence to the descending flow. Near the lower end of each of the partition walls 13, 14 a couple of air inlets 19, 20 and 21, 22, respectively (Fig. 2) are arranged. From the upper inlets 19 and 21 the air flows into the room to be heated in the direction of the arrow 'A' (Figs. 1 and 5), flowing through passages 23 and 24 and through lower outlets 25, 26, respectively, in the side members 3 and 4. As shown in Fig. 2, the outlets of the passages 25, 26 are located higher than their inlets. Consequently a rising flow of hot air is generated in the outlet passages 25, 26 creating a pressure drop in the passages 23, 24. From the lower air inlets 20, 22 the air flows in the direction of arrow 'B', i.e. below and past the passages 23, 24, respectively, and into the chambers of the side portions 11, 12 of the insert 9. At the upper part of said chambers there are arranged upper outlet passages 27, 28 extending through the structural side members 3, 4 respectively, into the room to be heated. A considerable pressure drop is thus created in the lower part of the chambers in the side portions 11, 12 of the insert 9 owing to the rising flow of hot air. The heat energy derived from the side portions of the metal insert is utilised for heating the air rising in the chambers of the side portions 11, 12. In the lower outlet passages 25, 26 there are arranged air control dampers 29, 30, and in the upper outlets 27, 28 there are provided air control dampers 31, 32 (Fig. 2) to control the hot air flowing out through those outlet passages. Thus the fire place according to this invention allows various operations: it can create intense heat emission at low pressure in the room to be heated, sending an air flow through the lower outlet passages 25, 26 into that room. Alternatively it can send hot air through the upper outlet passages 27, 28 into that room even when the pressure therein is not low enough for the operation mentioned above. As all the outlets into the room are situated higher than the air inlets 19, 20 and 21, 22 of the side portions 11, 12 of the insert 9, heated air can rise by natural convection circulation even when the pressure is not low enough in the room to be heated.This natural circulation causes air to flow down in the back portion 10 of the insert 9. As can be seen from Fig. 1, two air control passages 33, 34 are formed when placing the bottom plate 2 upon the base plate 1. Through these passages fresh air is led directly to the fire, flowing from both sides immediately under the hearths 7, 8. These hearths are strongly heated by the fuel burning on them, and consequently the aspirated air is heated before it reaches the combustion chamber. The amount of this primary air can be metered or throttled as desired by means of draught dampers 35 and 37. The flow of heated air to the room can be metered or throttled as desired by means of draught dampers 36 (Figs. 3, 4) and 360 (Fig. 3). WHAT WE CLAIM IS:-

1. A fire place installation for heating a room comprising a hearth, two side members flanking said hearth, a flue hood supported by said side members, and a double-walled metal insert surrounding said hearth from three sides within said side members and acting as a heat reflector, said insert being divided by partitions into a rear chamber and two side chambers, an air inlet being provided at the top of said rear chamber and an air passage being provided near the bottom of each partition leading from said rear chamber into each side chamber, an outlet being provided near the top of each side chamber leading through an aligned outlet in the associated side member.

2. A fire place installation according to claim 1, wherein a second outlet is provided.

near the bottom of each side chamber aligned

with an obliquely rising outlet in the associated side member issuing heated air into the room to be heated.

3. A fire place installation according to claim 1 or to claim 2, wherein a thermal insulation is provided between the outer faces of said metal insert and said side members.

4. A fire place installation according to claim 1 or to claim 2, wherein dampers are provided for the control of the air flow into said rear chamber and out of said side chambers.

5. A fire place installation according to claim 1, substantially as herein described with reference to the accompanying drawings.