[0001] The present invention relates to a device for heating enclosed spaces, such as aircraft
hangars, theaters, movie theaters, high-rise warehouses, and buildings used for commerce,
industry and handicraft, which are usually tall and have large surface areas.
[0002] Systems are known for this purpose that comprise a closed circuit composed of multiple
pipelines which are arranged approximately at the roof or ceiling of the enclosed
space; warm air is circulated inside these pipelines.
[0003] The heating effect is achieved by radiation from the surface of said pipelines towards
the floor by suitable insulating reflecting screens.
[0004] A system of this type is described in Italian patent no. 1,037,880, which includes
a burner located directly at the pipeline and a fan for feeding the gaseous heating
medium through the pipeline; the fan is located upstream or downstream of the burner.
[0005] The burner is of the blast type and is inserted at the pipeline, which has the configuration
of a closed loop.
[0006] This solution has a drawback: the use of air-blast burners in fact produces a preset
pressure in the pipeline, and this pressure requires continuous and accurate maintenance,
which must be performed by extremely qualified individuals, to check for any loss
from said pipeline.
[0007] Furthermore, the use of air-blast gas burners requires the manufacture of devices
which are complicated from a structural point of view and are difficult to optimize;
the large number of moving mechanical parts makes the device prone to breakages, and
thus to considerable maintenance, and entails high overall costs.
[0008] An aim of the present invention is therefore to solve the described technical problems,
eliminating the drawbacks of the described prior art and thus providing a device that
allows to heat enclosed spaces by radiation and has high-level safety characteristics
for its users.
[0009] Within the scope of this aim, an important object is to provide a device that has
very low manufacturing and maintenance costs.
[0010] Another object is to provide a device that is simple to set up, has a limited number
of moving mechanical parts, and allows the use of personnel that is not particularly
trained or qualified.
[0011] Another object is to provide a device for heating enclosed spaces by radiation which
has very low installation costs and is reliable and safe in use.
[0012] With the foregoing and other objects in view, there is provided a device as defined
in the appended claims.
[0013] Further characteristics and advantages of the invention will become apparent from
the detailed description of a particular embodiment, illustrated only by way of non-limitative
example in the accompanying drawings, wherein:
figures 1 and 2 are schematic views of the components of the device;
figure 3 is a sectional view of the fan of the burner;
figure 4 is a sectional view, taken along the plane IV-IV of figure 3;
figure 5 is a schematic view of the use of an air-stream burner.
[0014] With reference to the above figures, the reference numeral 1 generally designates
the heating device for enclosed spaces with any surface extension; said device comprises
at least one pipeline, designated by the reference numeral 2, which forms a closed
circuit that has the desired configuration according to the dimensions of the enclosed
space.
[0015] The device furthermore comprises an atmospheric multiple-flame Venturi-tube or air-stream
burner designated by the reference numeral 3.
[0016] The device is furthermore constituted by a fan, designated by the reference numeral
4, which is interposed at the pipeline 2 in a region that is adjacent to the burner
3 and is preferably contained together with said burner in a suitable containment
element 5 that has an appropriate insulation 6.
[0017] The fan 4 thus draws the burnt gas and sends it into a suitable chamber 7 arranged
laterally to the burner 3; downstream of said burner, the combustion gas and the flame,
which contains a certain amount of air drawn from outside and of burnt air, mix and
allow to obtain a high-temperature gaseous fluid without the aid of heat exchangers.
[0018] Preferably, a first gate valve 8 for adjusting the air flow-rate is inserted between
the fan 4 and the burner 3.
[0019] The fan 4 furthermore has a second gate valve 9 for adjusting the discharge of fumes
at a suitable discharge duct 10.
[0020] Of course there is a very specific ratio in the mixing of the air that circulates
inside the pipeline 2, of the product of combustion, and of the flame of the atmospheric
gas burner, since the mixed amount of air and gas required for combustion is equal
to the amount of combustion gas that leaves the discharge duct 10.
[0021] In this way, in this device primary air, generally designated by the reference numeral
11, enters the burner 3 due to the negative pressure produced by the jets of pressurized
combustible gas inside one or more Venturi-tube burners and due to the negative pressure
produced by the fan 4 on the feed duct 12 that is associated with said burner.
[0022] As shown in figures 1 and 2, the discharge duct 10 can furthermore be arranged at
the fan 4 or between the fan and the burner 3.
[0023] Furthermore, as shown in figures 3 and 4, advantageously the suction inlet 13 of
the fan 4 is located approximately at the center of the return duct 14.
[0024] As shown in figure 5, an air-stream burner 3 is used wherein the air and burnt gas
mixture is introduced laterally.
[0025] Air is fed upstream of the fan 4 by means of a third gate valve 15.
[0026] The dimensions of the device can be limited in this solution, too, by providing the
fan and the burner in a single unit.
[0027] It has thus been observed that the invention has achieved the intended aim and objects
a device having been provided that allows to heat enclosed spaces by radiation with
extremely high user safety characteristics, since the pipeline is at negative pressure
and thus does not release into the environment any toxic fumes due to accidental leaks
or breakages.
[0028] The possibility of providing in a single unit the fan and the burner, which is of
the Venturi-tube atmospheric type or of the air-stream type, allows to place said
unit in any point outside the enclosed space, due to its limited dimensions with respect
to known systems that have equal capabilities.
[0029] Its simple construction furthermore allows rapid and easy maintenance, which can
be performed even by personnel that is not particularly trained and thus with very
low manufacturing, installation, and management costs.
[0030] As regards the field of application, the described solution can be used to heat a
furnace, for example of the tunnel type.
[0031] The dimensions and the materials that constitute the individual components of the
device may of course be the most pertinent according to the specific requirements.
[0032] Where technical features mentioned in any claim are followed by reference signs,
those reference signs have been included for the sole purpose of increasing the intelligibility
of the claims and accordingly such reference signs do not have any limiting effect
on the scope of each element identified by way of example by such reference signs.
1. Device for heating enclosed spaces, comprising at least one closed-circuit pipeline,
which acts by heat radiation, a burner, and a fan, characterized in that said burner
is of the multiple-flame atmospheric-pressure type with Venturi tubes and in that
said fan injects air, drawn from said pipeline, laterally to said burner.
2. Device according to claim 1, characterized in that said atmospheric multiple-flame
burner with Venturi tubes is located in a region that is adjacent to said fan.
3. Device according to claims 1 and 2, characterized in that said burner and said fan
are located at a same containment element that has an appropriate insulation.
4. Device according to claims 1 and 3, characterized in that said fan draws the burnt
gas from said pipeline and sends it to a suitable chamber which is located laterally
to said burner, the combustion gases and the flame, which contains a certain amount
of air drawn from outside and of burnt air, mixing downstream of said burner.
5. Device according to one or more of the preceding claims, characterized in that said
Venturi-tube burner, of the atmospheric or air-stream type, produces a negative pressure
that allows to draw primary air from outside.
6. Device according to one or more of the preceding claims, characterized in that it
comprises a first gate valve which is interposed between said fan and said burner
or between said burner and a second gate valve that is connected to a discharge duct.
7. Device according to claims 1 and 6, characterized in that said discharge duct is located
at said fan or between said burner and said fan.
8. Device according to one or more of the preceding claims, characterized in that it
comprises at least one pipe, at least one air-stream or atmospheric Venturi-tube or
air-stream burner which has a lateral chamber to which the return duct of said at
least one pipeline can be connected.
9. Device according to one or more of the preceding claims, characterized in that said
fan has a suction inlet located approximately at the center of the return duct of
said at least one pipeline.
10. Device according to one or more of the preceding claims, characterized in that said
burner has a preheater for heating the comburent air which is suitable to increase
thermal efficiency.
11. Device according to one or more of the preceding claims, characterized in that said
air-stream burner laterally receives a mixture of air and burnt gases, said air being
drawn upstream of said fan.