JPH0325089Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a hot air heater, in particular, a warm air heater that blows hot air from the bottom of the machine and is placed on the floor of the room to be heated, and the operating time can be controlled with a timer. Regarding hot air heaters.

Conventional warm air heaters have a heating function, as shown in Figures 1 and 2, to prevent burns to the human body and abnormal heating of obstacles during operation using a timer, for example, when sleeping. In addition to the room temperature detection element 1 for controlling the air blowing temperature, there is a temperature sensing element 2 for preventing burns.
is provided. This temperature-sensitive element 2 for preventing burns
is attached to the ventilation passage 5 formed in the lower part of the fuselage 4 in order to detect the temperature when the hot air blown out hits the human body 3 and returns. The temperature of the ventilation passage 5 is slightly higher than the vicinity of the suction port 6 at the back of the machine body 4 where the room temperature sensing element 1 is installed, and when the temperature detected by the temperature sensing element 2 for preventing burns reaches a preset value. , timer operation is stopped. However, depending on the installation conditions of the fuselage 4, for example, if the fuselage 4 is installed in a corner of a room that should be heated, the room temperature detection element 1 may be activated first, which may pose a risk of low-temperature burns. occurs. Moreover, since the shape of the lower part of the fuselage 4 is special, compatibility is poor, manufacturing costs increase, and the design is also inferior.

The purpose of the present invention is to solve the above-mentioned technical problems and provide a hot air heater that prevents low-temperature burns by omitting the conventional thermal sensor for preventing burns, and has a simplified shape of the lower part of the machine. shall be.

The present invention is installed on the floor of a room to be heated so that hot air is blown out from the bottom of the body, and the timer is set so that the detected temperature of the room temperature detection element becomes the preset temperature that controls the room temperature. In a hot air heater that is configured to operate on a timer for a specified period of time, the room temperature sensing element is disposed near the suction port of the airframe, and the temperature detected by the room temperature sensing element is used to set a set temperature for controlling the room temperature. Means for level discrimination is provided at a predetermined set level corresponding to a temperature that exceeds and prevents burns, and means for stopping the timer operation when the detected temperature exceeds the set level during the timer operation. This hot air heater is characterized in that it is provided with:

Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 shows a hot air heater 10 according to an embodiment of the present invention.
FIG. 4 is a simplified side sectional view of FIG. 3. The body 11 of the warm-air heater 10 is placed on a floor 13 with a slight distance between it and a wall surface 12 of a room to be heated. Inside fuselage 11,
A combustor 14 that burns fuel such as city gas
and a heat exchanger 15 for exchanging heat between the combustion exhaust gas from the combustor 14 and air, and the combustion exhaust gas is discharged from the heat exchanger 15 to the outdoors via a duct (not shown) or the like. A suction port 16 is formed in the upper part of the rear surface of the fuselage 11, and the air sucked into the fuselage 11 through the suction port 16 by a suction fan 17 is heated by the heat exchanger 15 and becomes warm air. The air is blown out from the air outlet 18 formed at the bottom of the entire surface of the fuselage 11. Hot air heating is thereby achieved.

According to the present invention, the temperature-sensitive element for preventing burns in the prior art shown in FIGS. 1 and 2 is unnecessary, and the lower part of the fuselage 11 has a simplified structure without any ventilation passages. . A room temperature detection element 19, such as a thermistor, is provided near the suction port 16 on the back of the body 11. Room temperature sensing element 19
The room temperature is detected by the system, and the hot air blowing temperature is controlled based on the detected temperature, and according to the present invention, a burn prevention function is achieved during timer operation.

FIG. 5 is a diagram showing a control circuit for timer operation including the room temperature sensing element 19. A motor FM of the suction fan 17 is connected in series to the power source 20 . This motor FM has main switch MSW,
1st timer switch TMSW1 and 1st relay
A series circuit consisting of RL1 is connected in parallel, and the first
A timer TM is connected in parallel to relay RL1.
Further, in parallel with the series circuit consisting of the first timer switch TMSW1 and relay RL1, there is a series circuit consisting of the second timer switch TMSW2 and a motor CM for supplying combustion air to the combustor 14, and the primary winding of the transformer 21. 21a is connected.

The secondary winding 21b of the transformer 21 is connected to the rectifier circuit 22 via a self-holding switch HSW and a second relay switch RSW2 that are connected in parallel. This rectifier circuit 22 includes a second relay RL2.
and a first relay switch RSW1 are connected in series. The series circuit consisting of the second relay RL2 and the first relay switch RSW1 includes a series circuit consisting of the transistor TR and the combustion circuit 23, a series circuit consisting of the temperature adjustment circuit 24, the room temperature sensing element 19 and the variable resistor VR, and a series circuit consisting of the first relay switch RL2 and the first relay switch RSW1. Series circuits each consisting of a resistor R1 and a second resistor R2 are connected in parallel. A control voltage from the temperature control circuit 24 is applied to the base of the transistor TR. A connection point between the room temperature sensing element 19 and the variable resistor VR is connected to the temperature adjustment circuit 24 and to a non-inverting terminal of the comparator 25. 1st
The connection point between the second resistors R1 and R2 is the comparator 25
Connected to the inverted terminal of The output terminal of the comparator 25 is connected to the second relay RL2 and the first relay switch.
Connected to the connection point of RSW1.

Main switch MSW and self-holding switch
The HSW is linked to, for example, a gas tank (not shown) for supplying city gas to the combustor 14, and becomes conductive when the gas tank is opened. Note that the self-holding switch HSW shuts off when you take your hand off the gas tank. The first and second timer switches TMSW1 and TMSW2 are interlocked.

The temperature control circuit 24 controls the transistor TR so that the output of the room temperature detection element 19 becomes a predetermined constant value, and based on this, the solenoid valve in the combustion circuit 23 operates to adjust the combustion amount of the combustor 14. is controlled.

A reference voltage determined by the first and second resistors R1 and R2 is applied to the inverting terminal of the comparator 25,
When the output of the room temperature sensing element 19 exceeds the reference voltage level, the output of the comparator 25 becomes high level. The first relay switch RSW1 is a normally closed contact and is cut off when the first relay RL1 is energized. Further, the second relay switch RSW2 is a normally open contact, and the second relay becomes conductive when RL2 is excited.

In such a control circuit, when the timer operation is not performed, the first relay switch RSW1 is a normally closed contact, so the second relay switch RSW2
is self-maintained by the second relay RL2, and the temperature control circuit 24 controls the combustion circuit 23, thereby regulating the hot air to a constant temperature.

During timer operation, the first and second timer switches TMSW1 and TMSW2 are turned on to energize the first relay RL1, and the first relay switch RSW1 is accordingly cut off. At this time, when the output of the room temperature sensing element 19 is below a predetermined reference level, the output of the comparator 25 is at a low level, and therefore the second relay RL2 is energized.
The second relay switch RSW2 is self-held.
In this state, the hot air heating operation at a predetermined constant temperature is continued for the time set by the timer TM.
That is, the temperature adjustment circuit 24 controls the combustion circuit 23 by turning on/off the transistor TR so that the temperature detected by the room temperature detection element 19 is, for example, 20°C. As a result, the temperature detected by the room temperature sensing element 19 is maintained at, for example, 20°C.

As shown in FIGS. 3 and 4, the air outlet 18
If the output of the room temperature detection element 19 exceeds the reference level corresponding to a temperature that may cause low-temperature burns, such as 40°C, set by the resistors R1 and R2, due to the presence of a human body M in front of the The output of the device 25 becomes high level, and the second relay RL2 is demagnetized accordingly. Therefore, the relay switch RSW2 is cut off, and the power supply to the combustion circuit 23 via the conductive transistor TR is cut off, the solenoid valves etc. in the combustion circuit 23 are demagnetized, and the timer operation is stopped. Ru.

In the embodiment described above, the timer operation is stopped when the room temperature detection element 19 detects the predetermined temperature once, but in another embodiment of the present invention, the set temperature is stopped within a predetermined period of time. The timer operation may be stopped when the detection is performed a predetermined number of times. To this end, for example, the capacitor may be charged with the output when the room temperature detection element 19 detects the set temperature, and the timer operation may be stopped when the charging capacity exceeds a reference level.

As described above, according to the present invention, the burn prevention function can be achieved without providing the conventional burn prevention temperature sensing element, and therefore the structure of the lower part of the fuselage is simplified and manufacturing costs are reduced. At the same time, the aesthetic appearance improves.

[Brief explanation of the drawing]

Figure 1 is a front view showing the prior art, and Figure 2 is the front view of the prior art.
3 is a front view of one embodiment of the present invention, FIG. 4 is a simplified side sectional view of FIG. 3, and FIG. 5 is a simplified side sectional view of FIG. 3 and FIG. 3 is a diagram showing a control circuit including a room temperature sensing element 19. FIG. 10... Warm air heater, 11... Aircraft, 16...
Suction port, 19... Room temperature detection element, TM... Timer, 25... Comparator.

Claims (1)

[Claim for Utility Model Registration] The machine is placed on the floor of a room to be heated so that warm air is blown out from the bottom of the body, and the temperature detected by the room temperature detection element is the preset temperature for controlling the room temperature. In the hot air heater which is configured to perform timer operation for a time specified by a timer in this way, the room temperature sensing element is disposed near the suction port of the airframe, and the temperature detected by the room temperature sensing element is used to control the room temperature. Means for level discrimination is provided at a predetermined level corresponding to a temperature that exceeds a set temperature and that prevents burns, and when the detected temperature exceeds the set level during the timer operation, the timer operation is stopped. A hot air heater characterized by being provided with means for stopping. It is characterized by