Firebox with improved hot-air diffusion arrangement

Abstract

 The present invention refers to a firebox (1), in particular of the kind intended for residential use, comprising a hearth (2) in which combustion is generated, a heat exchanger (3) coupled to said hearth so as to promote heat exchange, at least one hot-air diffusion port branching off said heat exchanger (3), characterized in that it further comprises suction means (6) associated to said port, adapted to draw the hot air out of said heat exchanger (3) and diffuse it in the living areas therearound.

Description

[0001] The present invention refers to a firebox, in particular of the kind intended for residential use, provided with an improved arrangement for diffusing hot air into the living areas therearound.

[0002] Conventional fireboxes contain heat exchangers, inside and through which air is circulated for it to be heated up and be then diffused into the living space therearound through specially provided ports. The air may circulate in a natural way or it can be forced by means of fans. Possibly, filters of various kind may be provided to remove impurities carried by the air; the possibility also exists for scent dispensing means to be fitted in the air circulating circuit to agreeably perfume the same air.

[0003] Solutions of the above-cited kind are described, for example, in FR 2 706 589 and US 2005/0257787 patent publications.

[0004] In particular, currently available fireboxes are provided with a hearth, in which hot air is generated, and which is associated to a flue exhaust hood, at least one hot-air diffusion port branching off the chimney hood, and means to force outside cold air from the base of the firebox along the hearth until to flow ultimately out through said at least one hot-air diffusion port and provided in a lower portion of the firebox. These forced-circulation means are represented by a blower that forces cold air from the outside into a heat exchanger associated to a wall of the hearth, where the air is heated up and forced again, via appropriate conduits, into the outside through the above-mentioned hot-air diffusion ports.

[0005] It has been noticed that such kind of construction implies a number of drawbacks, such as the need for powerfully rated and largely sized blowers to be used in order to be able to overcome the flow resistance created by the heat exchanger, as well as to ensure an effective air flow rate at the hot-air diffusion ports. Moreover, it should be stressed that such blowers are rather noisy.

[0006] It is therefore a main object of the present invention to provide a system made up by a firebox and an improved arrangement for diffusing the hot air into the room in which the firebox is installed, said hot-air diffusion arrangement being connected to the heat exchanger via appropriate ducts.

[0007] It is another purpose of the present invention to improve the overall performance of the firebox by recovering a greater amount of heat energy, as well as increasing the flow rate of the hot air being diffused into the room, without any need arising for conventional heat exchangers to be modified structurally or more performing and more expensive blowers to be used, which would complicate the structure of the firebox itself.

[0008] In other words, the technical problem of the present invention lies in improving the efficiency of fireboxes while avoiding any need for modifications of the above-noted kind to be made often bulky and expensive.

[0009] A further purpose of the present invention is to convey the hot air generated by the heat exchanger much farther with a greater thermal efficiency.

[0010] Another purpose of the present invention is to place the improved hot-air diffusion arrangement also at a low level, i.e. at the floor level, without this affecting or limiting the performance.

[0011] Yet another purpose of the present invention is to produce a firebox provided with a plurality of operating parts for it to be able to ensure more satisfactory, all-round performance capabilities.

[0012] These and further aims are reached in a firebox that incorporates the features as defined in the appended claims at the end of the description.

[0013] Advantages and features of the present invention will anyway be more readily understood from the description that is given below by way of non-limiting example with reference to the accompanying drawings, in which:

• Figure 1A is a schematic, perspective rear elevational view of a firebox comprising an improved arrangement for the diffusion of heated-up air into the living space therearound according to the present invention;
• Figure 1B is a schematic, perspective front elevational view of the firebox shown in Figure 1A, as viewed in a possible condition of use;
• Figure 1C is a schematic, perspective front elevational view of the firebox shown in Figure 1A in a modified embodiment thereof;
• Figure 2 is a schematic exploded view of the hot-air outlet port of the improved arrangement for the diffusion of heated-up air into the living space therearound according to the present invention;
• Figure 3 is a schematic, perspective partially cross-sectional view of the arrangement shown in Figure 2, as viewed in the assembled state thereof;
• Figure 4 is a schematic perspective view of the arrangement shown in Figure 2, as viewed in a partially assembled state thereof, according to a modified embodiment.

[0014] As noted hereinbefore, the basic idea at the roots of the present invention lies in devising a structure of a firebox which enables the main component parts thereof, such as the hearth, the heat exchanger and the forced- circulation means for the room air, to be kept substantially unaltered, thereby doing away with any need whatsoever for more powerful, noisier and oversized component parts to improve the efficiency of the firebox.

[0015] Therefore, it has been found that, if a conventional suction fan positioned at the level of the hot-air diffusion ports is used instead of the afore-mentioned blower positioned at the base of the firebox, all afore-indicated aims are reached.

[0016] As a result, the object of the present invention is a firebox, in particular of the kind intended for residential use, as recited in the appended claims.

[0017] In particular, as shown in Figures 1 A to 1C, the firebox 1 comprises a hearth or combustion chamber 2, a heat exchanger 3 associated to said hearth so as to ensure adequate heat-exchange, a hood 4 for exhausting fumes, and at least one hot-air diffusion port 5.

[0018] Advantageously, suction means 6 are associated to said hot-air diffusion port 5 to draw in the hot air from the firebox and diffuse it into the room therearound. Preferably, said suction means 6 are represented by a suction fan.

[0019] The suction means 6 are therefore positioned at a point located downstream from the flowpath that the outside air must follow to be heated up and blown again into the room, that is exactly the opposite of what is generally the case in prior-art fireboxes, in which, as already noted hereinbefore, a blower is positioned just upstream to said flowpath. In other words, the suction means 6 are positioned close to the point at which the hot air is let out from the firebox.

[0020] Furthermore, the suction means 6 may be mounted outside the hot-air diffusion port 5, as this is best illustrated in Figures 2 to 4, so as to intercept the flowpath of the heated air prior to its being blown out of the same port. As an alternative, such means may be housed inside the port assembly.

[0021] By having said suction means 6 arranged directly at the level of the hot-air diffusion port 5, considerable advantages can be achieved in terms of both performance capabilities and energy usage, noise and space requirements.

[0022] In fact, it has been noticed that a moderately sized and rated conventional fan is fully capable of coping with the requirements of the particular application, since suction, when situated on the upper side of the firebox in this way, is able to take advantage from the natural tendency of hot air to move upwards, while being at the same time effective in applying a negative pressure upstream of the flowpath of the air, which tends to draw in air from the lower portion of the firebox.

[0023] The combination of the above-cited effects is such as to bring about an increase in the performance capabilities of the inventive firebox by more than 30 percent as compared with conventional fireboxes having the blower situated at the base thereof or, in other words, upstream of the flowpath followed by the air to be heated. At the same time, use is made of less performing fans with a significant saving effect in terms of reduced energy usage, costs and noise.

[0024] It has furthermore been found that the above-indicated advantages are even more conspicuous in the case that the heated air is remotely conveyed, via appropriately insulated ducts, since the air output rate is such as to ensure optimum effectiveness also at distances of 6 to 8 metres from the firebox.

[0025] According to a first modified embodiment of the present invention, the hot-air diffusion port may also be positioned at the lower portion so that the hot air can be blown out at the level of the floor, without affecting the overall performance of the firebox.

[0026] Figures 2 and 3 illustrate the hot-air diffusion port 5 according to the present invention. The port 5 comprises a first box-shaped element 7 coupled with a connecting member 8 for connection with a duct 9 receiving the hot air from the heat exchanger 3. The above-cited suction means 6 are accommodated between the port 5 and the connecting member 8.

[0027] The first box-shaped element 7 of the port 5 is provided with a heated-air inflow aperture 10 that is formed in the bottom thereof, and a heated-air outflow aperture 11 opposite to said inflow aperture. The inflow aperture 10 fluidly communicates with the suction means 6, whereas the outflow aperture 11 is delimited by a second box-shaped element 12 of the port 5 adapted to be fitted into said first box-shaped element 7.

[0028] Preferably, as illustrated in Figure 3, said second box-shaped element 12 is provided with walls 13 for the flow of the outflowing air to be properly channelled.

[0029] More preferably, the hot-air diffusion port 5 comprises a filter 16, as shown in Figures 1B and 1C, provided to clean the hot air flowing out from the port 5. This filter may for instance be reversibly mounted outside the port for more convenient replacement or cleaning. Alternatively, it can be accommodated within the first box-shaped element 7 so as to be able to intercept the flow of heated air prior to its flowing out from the port 5.

[0030] According to another modified embodiment of the present invention, the bottom portion of the first box-shaped element 7 may accommodate a lighting member 14, such as for instance a courtesy lamp.

[0031] According to yet another modified embodiment, as shown in Figure 4, the diffusion port 5 may include a removable container 15 for substances intended to perfume and/or humidify the hot air to be diffused. In particular, the container 15 may be subdivided in two distinct parts, so that it will contain just the water needed for air humidification on the one side and, on the other side, a perfuming substance, either in a liquid form or on a conventional solid carrier.

[0032] Yet another modified embodiment may contemplate a loudspeaker (not shown) being provided for the diffusion of music, as duly associated to said hot-air diffusion port and appropriately insulated in order to prevent it from being damaged by the heat.

[0033] The diffuser port 5, the suction means 6 and the joining member 8 are associated with each other with the aid of conventional fastening means, such as screws and corresponding lock-nuts, snap-fitting releasable joining means, joining means by the mating of shapes, welding or suitable bonding.

[0034] In particular, the connecting member 8 is further connected to the duct 9 so as to receive in a fluid-tight manner the air flowing in from the heat exchanger 3, in a basically conventional manner.

[0035] Fully apparent from the foregoing description is therefore the ability of the present invention to effectively reach the afore-indicated aims.

[0036] It will be readily appreciated that the inventive firebox as described above may be the subject of a number of modifications that are within the abilities of those skilled in the art. So, for example, sizes, materials and shapes may each time be selected so as to more effectively comply with particular needs or preferences, without departing from the scope of the present invention as defined by the following claims.

Claims

1. Firebox (1), in particular of the kind intended for residential use, comprising a hearth (2) in which combustion is generated, a heat exchanger (3) coupled to said hearth so as to promote heat exchange, at least one hot-air diffusion port (5) branching off said heat exchanger (3), characterized in that it further comprises suction means (6) associated to said port, adapted to draw the hot air out of said heat exchanger (3) and diffuse it in the living areas therearound.

2. Firebox (1) according to claim 1, wherein said suction means (6) are positioned downstream from the flowpath which the outside air is due to follow to be heated up and be diffused again into the room.

3. Firebox (1) according to claim 1 or 2, wherein said suction means (6) comprise at least one suction fan.

4. Firebox (1) according to any of the claims 1 to 3, wherein said suction means (6) are positioned close to said at least one hot-air diffusion port (5).

5. Firebox (1) according to any of the claims 1 to 4, wherein said at least one hot-air diffusion port (5) comprises a container (15) for substances adapted to perfume the hot air being let out from the port, and/or a further container for the humidification of said outflowing hot air.

6. Firebox (1) according to any of the claims 1 to 5, wherein within said hot-air diffusion port (5) there is housed a filter for cleaning the hot air being let out from said port.

7. Firebox (1) according to any of the claims 1 to 6, wherein within said hot-air diffusion port (5) there is housed a lighting member (14).

8. Firebox (1) according to any of the claims 1 to 7, further comprising a music-diffusing loudspeaker associated to said hot-air diffusion port (5).

Drawing