JPH0370908A - Air blower for combustion - Google Patents

Abstract

PURPOSE:To provide a blower for combustion air with low noises and without raising temperature that is capable of improving the performance of blast delivery by constituting a body of casing of metallic outside casings and an inner casings comprising layers made of porous materials the specific gravities of which change continuously in the direction of thickness. CONSTITUTION:A blower for the air used for combustion is constituted of outside casings 9 and 10 made of metal plates and inside casings 16 and 17. The porous construction body of the inside casings is constituted of a solid fused layer 19 of a large specific gravity, high porosity material layer 19 which is of a low specific gravity and has the porosity which changes in the direction of thickness, and skin layer 20 which has specific gravity between that of the fused layer 18 and that of the porous layer 19. The effects of sound absorption and heat insulation are, therefore, large and noises are low by the use of high porosity material in the inner casings 16 and 17, and it is possible to suppress a rise of temperature in the outer casings 9 and 10 made of metal plates caused by the high temperature of the air for combustion after it has exchanged heat with the exhaust gas. Furthermore, it becomes easy to form a cut-off section 17a in an ideal shape and also finish the outlet section A, 16a and outlet section B, 17b with curved surfaces which give no disturbance to fluid flow, improving the performance of blast delivery.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a combustion air blower used in a hot air heater that burns fuel such as gas or oil and uses the heat to heat the room. .

[Prior Art] Fig. 4 is a vertical sectional view and a side view of a conventional hot air heater disclosed in, for example, Japanese Utility Model Application Publication No. 58-33941. In the figure, (1) is the main body of the hot air heater. , (2) is a convection blower, (3) is a combustion air blower, (4) is a combustion air blower motor, (5) is a combustor, (6) is a heat exchanger, (7
) is the top of the air supply and exhaust pipe with a double cylindrical structure shown in Utility Model Application Publication No. 58-107437, in which the air supply flow path is formed on the outside and the exhaust flow path is formed on the inside. (8) is the partition wall that separates indoor and outdoor areas. be.

In the above configuration, combustion air is supplied outdoors separated by the partition wall (8), flows through the flow path outside the supply/exhaust pipe top (7), and is sent to the combustion air blower* (3). It is then supplied to the combustor (5). Here, the heat generated by burning the fuel is exchanged with the convection air blown from the convection blower (2) in the heat exchanger (6) and is blown as warm air for heating. is the top of the air supply and exhaust pipe (7
) and is discharged outdoors. At this supply/exhaust stack top (7), heat is exchanged from the exhaust gas to the supply air, so the temperature of the air flowing into the combustion air blower fi (3) is higher than the outdoor air temperature. There is.

FIG. 5 is a front sectional view and a side sectional view showing the configuration of a conventional combustion air blower (3). In the figure, (9) is a casing A, and (10) is a casing B, both of which are made of metal plates. It has a blade (12) inside, a cut-off part (LOA), a suction part (14), and a discharge part (15), and the two are joined by a caulked joint part (10c). The motor mounting foot (11) is fixed to the casing B (10) and holds the combustion air blower motor (4), and the backing (13) connects the combustion air blower motor (4) and the casing B (10). Airtightness is maintained between the two.

In this conventional combustion air blower, the blower casing was formed of a metal plate, and did not have sound absorption or heat insulation effects. Also, due to limitations in metal plate processing, the ventilation performance is limited.

There was a point where we had to compromise on the shape of the cut-off part shown by (LOa) instead of the desired shape of the soft-off part shown by the - dotted chain line in (job).

[Problems to be Solved by the Invention] A conventional combustion air blower is configured as described above, and the casing used therein is made of metal, and no consideration has been given to sound absorption or heat insulation.

Generally, in blowers for this type of use, the driving motor is often of a high rotation type in order to obtain high wind pressure, and reducing the noise generated from this blower is an important design issue. Various efforts have been made to optimize the shapes of the blades and casing.

Further, air heated to a high temperature by exchanging heat with exhaust gas flows into a combustion air blower used in a forced air supply/exhaust type hot air heater. This high-temperature air heats the casing of the combustion air blower, thereby increasing the temperature of the surrounding area, especially the temperature of the control device, which is made up of electronic components that do not like high temperatures and is located near the combustion air blower inside the hot air heater body. There was a problem in increasing the

This invention was made to solve the above-mentioned problems, and provides a combustion air blower that has low noise, does not raise the surrounding temperature, and can easily improve air blowing performance. The purpose is to obtain.

[Means for Solving the Problems] A combustion air blower according to the present invention has a casing body that is
It consists of an outer casing made of metal and an inner casing made of a porous structure having a porous layer formed on the inner surface of the outer casing with a porous layer whose specific gravity is continuously varied in the thickness direction of the layer. .

[Function] In this invention, since the inner casing made of a porous structure is provided, the sound absorption and heat insulation effects are improved, and the degree of freedom in forming the shape of the casing is increased, making it possible to obtain the optimal shape for air blowing performance. It becomes possible.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
The figures are a front sectional view, a side sectional view, and a partially enlarged view showing an embodiment of the present invention.
, (12) is a blade, (14) is a suction part, (15) is a discharge part, (16) is an inner casing body made of a porous structure, and (17) is also an inner casing B, and this porous structure is composed of synthetic resin, and as shown in the enlarged view, it consists of a solid fusion/I (18) with a high specific gravity, a porous layer (19) with a low specific gravity and a porosity that changes in the thickness direction, and It is formed of a skin layer (20) whose specific gravity is between the fused layer (18) and the porous layer (19), and is manufactured by molding.

Since the casing body of this embodiment is constructed as described above, the porous layers of the inner casings (16) and (17) have a large sound absorption effect and heat insulation effect, generate less noise, and are able to exchange heat with exhaust gas. This suppresses the temperature rise of the outer casing (9) and (10) made of metal plates due to high-temperature combustion air, reduces heat radiation into the hot air heater body, and increases the ambient temperature of the control circuit located nearby. There is no stress, and compared to the conventional foam material lining,
The shape of the casing body can be formed accurately. Therefore, it is easier to form the cut-off part (17a) into an ideal shape compared to the conventional case made of only a metal plate casing, and furthermore, the outlet part A (16a) and the outlet part B (17b) are also It becomes easy to apply a curved surface finish so as not to disturb the flow of the material. In this way, a combustion air blower with improved basic blowing performance, low noise and low heat radiation to the outside can be obtained.

FIG. 2 is a front sectional view, a side sectional view, and a partially enlarged view showing another embodiment of the present invention. In the figure, (21) indicates a convex portion on the inner casing A side and a concave groove on the inner casing B side. This is the seal portion in which the inner casing (16) (17) formed of the porous structure can be more reliably sealed.

FIG. 3 is a front sectional view showing still another embodiment of the present invention;
The side sectional view and partially enlarged view show that in this embodiment, the outer casing A made of a metal plate is also used as the main body (1) of the hot air heater, and the main body (1) of the hot air heater has porous holes. Inner casing (16) (17) consisting of a quality structure
Stack the outer casing B (10) and tighten the screws (
22) etc. by fixing.

A combustion air blower is integrally formed in the hot air heater body. According to this configuration, a member for fixing the combustion air blower to the hot air heater main body is not required, and a rational fixing structure with high mounting rigidity can be obtained.

In addition, this combustion air blower is often placed near the combustor, and is connected to the combustor by a joint member, so the porous structure is made of non-flammable or flame-retardant material. By using a durable material, safety can be further improved.

[Effects of the Invention] As described above, according to the present invention, the casing body of the combustion air blower is made of a metal outer casing, and the specific gravity formed on the inner surface of the outer casing is made continuous in the thickness direction of the layer. The inner casing is made of a porous structure with a porous layer that has been changed to a combustion engine that produces low noise and does not raise the surrounding temperature, and can easily improve air blowing performance. It has the effect of being able to obtain an air blower for use.

[Brief explanation of drawings]

1 is a front sectional view, a side sectional view, and a partially enlarged view showing one embodiment of the present invention; FIG. 2 is a front sectional view, a side sectional view, and a partially enlarged view showing another embodiment of the present invention; FIG. 3 is a front sectional view, side sectional view, and partially enlarged view showing still another embodiment of the present invention, FIG. 4 is a vertical sectional view and side view showing a conventional hot air heater, and FIG. It is a front sectional view and a side sectional view showing a conventional blower for combustion air. In the figure, (1) is the hot air heater main body, (3) is the combustion air blower, (9) and (10) are the outer casing made of metal plate, (12) is the blade, (14) is the suction part, ( 15) is a discharge part, (16) (17) is an inner casing made of a porous structure, (18) is a fusion layer, (19) is a porous layer, and (20) is a skin layer. The same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] A hot air heater that performs heating by exchanging heat generated by combustion of fuel with convection air via a heat exchanger, or by mixing combustion gas and convection air to warm air. In the combustion air blower that blows the air necessary for the combustion of the fuel, the casing body of the combustion air blower is made of a metal outer casing, and the specific gravity formed on the inner surface of the outer casing is adjusted in the thickness direction of the layer. 1. A combustion air blower comprising: an inner casing made of a porous structure having a porous layer having a continuously changed porous layer;