JP2638732B2 - Hot air heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in the detection accuracy of a room temperature in a warm air heater of a system for automatically controlling a room temperature set by a user.

[0002]

2. Description of the Related Art A casing provided with an air inlet and a hot air outlet, a heating source mounted in the casing, air sucked from the inlet mounted in the casing and the outlet A blower that blows out hot air, a temperature sensor attached near the suction port of the casing, connected to the temperature sensor via a lead wire, and input a room temperature detected by the temperature sensor,
A hot air heater having a control unit for controlling the heating source and the like is used. In this warm air heater, the amount of heat generated by the heating source and the amount of air blown out by the blower are controlled while detecting the room temperature with a temperature sensor so that the room temperature set by the user is obtained. Further, the temperature sensor is usually installed at the air intake of the casing in order to detect the room temperature as accurately as possible. By the way, in recent years, the casing has been significantly reduced in size due to improvement in the heating capacity of the heating source and downsizing of the control unit.

[0003]

However, especially in the case where the casing is downsized, the temperature in the casing tends to rise because the blowout temperature is the same as that of the conventional one even if the casing is downsized. Also, the lead wire is arranged along the casing wall etc. between the temperature sensor and the control unit, and when passing through a high temperature part of the hot air heater such as near the heating source due to the wiring layout. There are many. The inventor of the present application has found that even if the temperature sensor is installed near the air intake where an atmospheric humidity close to room temperature can be obtained, the temperature sensor becomes high due to heat conduction from the high temperature portion of the lead wire, and the room temperature is accurately detected. I found that there are many cases where it is impossible. SUMMARY OF THE INVENTION An object of the present invention is to provide a warm air heater that can remove the adverse effect of heat conduction through a lead wire with a very simple configuration and can accurately detect room temperature by a temperature sensor.

[0004]

SUMMARY OF THE INVENTION A hot air heater according to the present invention includes a casing having an air inlet and a hot air outlet, a heating source mounted in the casing, and a heat source mounted in the casing. A blower that sucks air from the suction port and blows out hot air from the air outlet, a temperature sensor attached near the suction port of the casing,
A warm air heater connected to the temperature sensor via a lead wire and having a control unit for controlling the operation of the heating source by inputting the room temperature detected by the temperature sensor, A portion extending a sufficient length from the connection portion of the lead wire to the temperature sensor faces the suction port such that the vicinity of the connection portion to the temperature sensor is cooled by the suction air from the suction port. A hot air heater. In the configuration of claim 2, the temperature sensor is attached to a substantially center of an inner surface of a lid with a vent provided in the suction port, and a portion extending a sufficient length from a connection portion of the lead wire to the temperature sensor is: The lead wire is attached to the inside of the lid as a spiral portion provided in the vicinity of the connection portion to the temperature sensor.

[0005]

According to the present invention, a sufficient length is provided from the connection portion of the lead wire to the temperature sensor so that the vicinity of the connection portion of the lead wire to the temperature sensor is cooled by the suction air from the suction port. The extended part faces the inlet of the casing. For this reason, even if there is a high-temperature portion in the lead wire on the way from the control unit to the temperature sensor, the lead wire is cooled by the suction air, and the transmission of heat to the temperature sensor is prevented. Thus, the temperature sensor is always maintained at the suction air temperature, and can accurately detect the room temperature. As a result, the room temperature can be accurately detected with a very simple configuration, and the room can be smoothly heated by the warm air heater.

[0006]

1 shows a hot air heater 1. FIG. Hot air heater 1
Has a casing 2 made of an iron plate, a hot air outlet 22 is opened at a lower portion of a front surface 21 of the casing 2, and a convection air inlet 24 and a combustion air inlet 25 are provided at an upper portion of a back surface 23.
Are juxtaposed. The convection air suction port 24 and the combustion air suction port 25 are both covered by a rectangular plate-shaped common filter 26 detachably mounted on the back surface 23.

As shown in FIG. 4, a gas burner 3 as a heating source and a blower 4 are provided in the casing 2. Fuel gas is supplied to the gas burner 3 from a gas pipe 34 in which a main valve 31, a safety valve 32, and a flow control valve 33 are interposed, and combustion air is supplied from the suction port 25. Inside the gas burner 3, an ignition device 35 and a combustion detection device 36 such as an acid-deficient fire are mounted. Blower 4
Has a fan 41 disposed inside the outlet 22 and a motor 42 for driving the fan 41. As indicated by arrows, the convection air inlet 24 and the combustion air inlet 25 Along with sucking indoor air, warm air is blown out from the outlet 22.

A control unit 5 which is an electronic control unit is mounted in the casing 2 and controls the gas burner 3 and the blower 4. The control unit 5 is usually mounted on the side of the casing 2 to avoid unstable operation of the electronic circuit due to high temperatures. As shown in FIG. 2, the convection air suction port 24 has a grill structure in which a number of horizontally long ventilation holes are vertically arranged. Combustion air inlet 2
5 is provided with a grill-shaped lid 6 having a large number of horizontal slit-shaped vent holes 60 provided in two rows in the vertical direction.

As shown in FIG. 3, a temperature sensor 7 is provided at the center on the inner surface of the lid 6, and the temperature sensor 7 is connected to the control unit 5 via a lead wire 8. In this embodiment, the temperature sensor 7 is connected to a lead wire 8 through a notch 63 at the tip of a bracket 62 protruding from an inner surface 61 of the lid 6.
Is fixed by fitting. Control unit 5
Inputs the room temperature (suction air temperature) detected by the temperature sensor 7 and the set temperature of the temperature setting switch 11 (shown in FIG. 4), and appropriately controls the operation of the gas burner 3 and the blower 4.

The vicinity of the connection portion of the lead wire 8 to the temperature sensor 7 is a portion extending a sufficient length from the connection portion of the lead wire 8 to the temperature sensor 7 so as to be cooled by the air sucked from the suction port 25. Facing the suction port 25 of the casing to form a long cooling portion 81. Long cooling part 8
In this embodiment, 1 is arranged around a number of brackets 62 projecting from an inner surface 61 of the lid 6 and is spirally arranged around the temperature sensor 7. Thus, the long cooling portion 81 of the lead wire 8 is smoothly cooled by the room air sucked from the suction port 25. In other words, the long cooling portion 81 prevents conduction of heat from the high-temperature portion to the temperature sensor 7 even if a high-temperature portion exists in the lead wire 8 in the middle of the wiring from the control unit 5 to the temperature sensor 7. I do. As a result, the temperature of the temperature sensor 7 increases due to the heat transfer from the lead wire 8,
It is possible to prevent the output above room temperature from being generated, and the temperature sensor 7
Improves the detection accuracy of the room temperature.

The long cooling portion 81 can be formed in any desired pattern such as a meandering shape, a star shape, a flower shape and the like in addition to the spiral shape of the above embodiment. Any other position such as a position close to the suction port 24 may be a place that can be cooled by the suction air. Further, the heating source may be an electric heat source or a petroleum fuel. In the above embodiment, the long cooling portion 81 is wired by the bracket 62 so as to be separated from the inner surface 61 of the lid 6, but may be in contact with the inner surface 61. Note that the remote state (for example, 5
mm), the long cooling part 81 that comes into contact with the suction air
Surface area is increased, and the cooling effect is great.

[Brief description of the drawings]

FIG. 1 is a perspective view from behind a hot air heater.

FIG. 2 is a rear view of the hot air heater with a common filter removed.

FIG. 3 is an enlarged perspective view of the lid of the suction port as viewed from the inside.

FIG. 4 is a schematic configuration diagram of a hot air heater.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hot air heater 2 Casing 22 Outlet 24, 25 Inlet 3 Gas burner (heating source) 4 Blower 5 Control unit 6 Lid 60 Ventilation hole 7 Temperature sensor 8 Lead wire 81 Cooling long part

Claims (2)

(57) [Claims] 1. A casing provided with an air inlet and a hot air outlet, a heating source mounted in the casing, and air sucked from the inlet mounted in the casing and the outlet. A blower that blows out hot air, a temperature sensor attached to the suction port of the casing, and a temperature sensor connected to the temperature sensor via a lead wire. A control unit for controlling the operation of the source , wherein the vicinity of the connection portion of the lead wire to the temperature sensor,
Reed so that it is cooled by the air sucked from the suction port
A section of sufficient length from the connection of the wire to the temperature sensor
A warm air heater having the opening facing the inlet . 2. The temperature sensor according to claim 1, wherein the temperature sensor is mounted substantially at the center of an inner surface of a lid with a vent provided in the suction port, and a connection portion of the lead wire to the temperature sensor.
A hot air heater having a portion extending from the cover to a sufficient length as a helical portion provided near a connection portion of the lead wire to the temperature sensor, which is attached to the inside of the lid.