JPH0320564A - Hot air heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a hot air heater that is open to a room and heats the room by blowing combustion gas into the room. 2. Description of the Related Art In general, indoor open type hot air heaters are equipped with a burner section 21, a combustion tube 22 and a duct 23 that guide combustion gas from the burner section, and a combustion tube 22 and a duct 23, as shown in FIG. Wind from the convection blower 24 provided oppositely to the combustion tube 2
The combustion gas discharged from the outlet 25 is mixed with the combustion gas discharged from the outlet 25.
It blows out warmer air to heat the room.

Problems to be Solved by the Invention However, in the conventional structure described above, the convection blower 24 protrudes largely from the back of the main body. Therefore, in order to make the device more compact, the inventors considered housing the convection blower 24 inside the main body 26, reducing the protrusion caused by the fan guard 27 on the back of the main body, and making the propeller fan 24a smaller as well. However, in this case, as the protrusion of the fan guard 27 is reduced, the opening area of the convection air intake hole 28 provided in the fan guard 27 is also reduced, resulting in the following problem. In other words, in such a configuration,
There is no problem when the device is in the initial α state of use, but as the combustion time becomes longer, indoor dust adheres to the fan guard 27 in a short time and begins to block the convection air intake hole 28. As a result, the amount of air blown by the convection blower 24 is reduced in a short time, and if the device is equipped with an overheating prevention device, this will be activated in a short time and the operation of the device will automatically stop, so please check the fan guard 27 frequently. If the attached dust is not removed, the equipment will not be able to continue operating.
Additionally, the temperature of the unit rose within a short period of time, which was a drawback in terms of safety. The present invention was created in view of the above problems, and aims to make the equipment more compact by preventing air volume from decreasing due to dust buildup in a short period of time. Means for Solving the Problems In order to solve the above problem, the hot IR heater of the present invention includes a burner that performs combustion, a combustion tube provided to cover the burner, and a box provided to cover the burner and combustion tube. a convection blower attached to the back of the main body so as to supply hot air into the duct; a fan of the convection blower is installed inside the duct; A bell mouth plate is installed at the rear of the duct,
In addition, ventilation holes are provided in the duct surrounding wall located behind this bell mouth plate. The present invention has the above-mentioned configuration, so even if the opening area of the convection air intake hole of the fan guard is small and dust adheres to the fan guard in a short period of time, indoor air is taken in through the ventilation hole of the duct, so the rate of decrease in air volume is reduced. It is small and can prevent a sudden drop in air volume. Therefore, it is possible to prevent the temperature of the duct body from rising due to a decrease in air volume, and to maintain operation for a long time without having to frequently remove dust attached to the fan guard net. Furthermore, it is possible to prevent the main unit from overheating due to a reduction in air flow, and it is possible to provide a compact warm air heater that is highly dust resistant and highly safe. A hot air heater according to an embodiment of the present invention other than the embodiment will be described with reference to the drawings. In FIG. 1, 1 is a main body having a hot air outlet 2 on the front, 3 is a burner installed on one unit 4 of this main body 1 via a leg 5, and in this embodiment, it is used to vaporize liquid fuel. A burner is used for combustion. Reference numeral 6 denotes a combustion cylinder that covers above the burner 3. A catalyst 7 having many ventilation holes is provided in the upper part, and a plurality of air intake ports 8 are formed in the lower peripheral wall. Reference numeral 9 indicates a guide plate for improving air intake into the air intake port 8, 10 indicates a horseshoe-shaped duct provided inside the main body so as to surround the combustion tube 6, and a bell mouth plate 11 is attached to the inner rear part. ．． Reference numeral 12 denotes a convection blower that supplies hot air into the duct 10, and is attached to the rear of the main body via a fan guard 13. This convection blower has its propeller fan 12a located inside the duct 10 and facing the bell mouth plate 11, so that the protrusion from the back of the main body is reduced accordingly. The fan guard 13 has numerous air intake holes on its rear surface and all around the surface.
4 has a strong appearance, but there are fewer air intake holes 14 on the dividing surface with a smaller protruding dimension, that is, there are fewer air intake holes 14 in the entire fan guard. 15 is this air intake. This is a ventilation hole to compensate for the reduced number of holes 14.
There are multiple convection blowers 12 on the peripheral wall of the duct behind the bell mouth fill, and the convection blowers 12 also suck air from these ventilation holes 15. In the figure, l6 is an overheating prevention device installed on the upper wall of duct 0, and l7 is a wind control plate. In the above structure, the combustion flame formed by the burner 3 is
The indoor air obtained by the convection blower l2 through the convection air intake hole l4 provided in the fan guard 13 and the ventilation hole l5 provided in the duct peripheral wall behind the bell mouth plate 11 is supplied to the air below the combustion tube 6. The flame is supplied through the suction hole 8 and becomes a complete combustion flame. Combustion heat from this combustion flame heats the combustion tube 6, and combustion gas passes through the catalyst 7 and is discharged outside the combustion tube 6. On the other hand, the air sent from the convection blower l2 exchanges heat with the combustion tube 6, mixes with combustion gas, is guided to the duct 10, and is discharged indoors as warm air from the outlet 2 to heat the room. ．． Here, the opening area of the convection air intake hole 14 of the fan guard l3 is small, and the fan guard 1
Even if the convective air intake hole 14 is blocked by dust, the indoor air is taken in through the ventilation hole 15 of the duct 10, so the reduction rate of the hot air volume is small and a sudden drop in the air volume can be prevented. can. Therefore, the amount of combustion air introduced into the combustion tube 6 does not decrease in a short time due to a decrease in air volume due to dust adhesion on the fan guard 13, and C
Deterioration of exhaust gas performance such as O generation can be prevented as much as possible. In addition, by reducing the air volume, the temperature of the overheat prevention device 16 installed at the top of the duct 10 will not rise in a short period of time, and the equipment can continue to operate for a long time without frequently removing dust attached to the fan guard 13. be able to. Furthermore, it is possible to prevent the duct 10 and the main body 1 from overheating due to a reduction in the amount of air flow, and it is possible to provide a compact point-air heater with excellent dust resistance and high safety.

Effects of the Invention As is clear from the description of the embodiments, the present invention can make the equipment more compact and compensate for the reduction in air volume due to the reduction in the area of the convection air intake hole of the fan guard, resulting in a small and compact equipment. can be provided. In addition, even if the convection air intake hole area of the fan guard is small, it can prevent the air volume from decreasing in a short period of time due to dust adhesion, which can prevent overheating prevention devices from operating in a short period of time, and also prevent abnormal overheating of equipment. etc., it is possible to obtain a compact hot air heater with excellent dust resistance and high safety.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a hot air heater according to an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional hot air heater.

Claims (1)

[Claims] A burner that performs combustion, a combustion tube provided to cover the burner, a box-shaped duct provided to cover the burner and combustion tube, and a convection device attached to the back of the main body to supply hot air into the duct. a convection blower, and a fan of the convection blower is incorporated inside the duct,
This hot air heater has a bell mouth plate provided at the rear of the duct facing the fan, and ventilation holes provided in the duct peripheral wall located behind the bell mouth plate.