JPS592447Y2 - Safety devices for hot air heaters - Google Patents

Description

[Detailed description of the invention] This invention relates to a hot air heater, and in particular, when a wind shield such as a human body comes into contact with the hot air blown out, it may cause burns if it is a human body, or it may cause burns if it is caused by other objects. The object is to provide a safety device that can prevent the risk of fire or damage caused by overheating.

In hot air heaters that use fuel such as white kerosene, the temperature near the hot air outlet is quite high, and the temperature in the vicinity of the hot air outlet is quite high. If human skin is exposed for a considerable period of time at a distance of 1,000 cm, there is a risk of high-temperature burns. However, exposure to hot air for a considerable period of time can cause low-temperature burns.

Furthermore, even if it is not a human body, it is not preferable to leave an object that would be thermally deformed by rising temperature in close proximity to the hot air outlet.

However, with conventional heaters, we are aware that there is a danger if a person or other wind blocker gets close to the hot air outlet, but the instruction manual explains how to avoid touching the outlet or getting close to the outlet. The device merely issued a warning, and no further rational measures were taken on the equipment side, resulting in burns to young children and the elderly, and foreign objects to the hot air outlet. There were still cases of cars falling over or getting thermally deformed, and there was a need for some sort of safety device to be installed.

In view of the actual situation, the present invention detects the occurrence of the various abnormal conditions mentioned above as soon as possible, and automatically and proactively stops the heating function, such as by interrupting the heating operation, thereby preventing various accidents. The purpose of the present invention is to provide a novel safety device for hot-air heaters that can prevent the above from occurring, and embodiments of the present invention will be specifically described below with reference to embodiments shown in the accompanying drawings.

Fig. 1 shows a floor-mounted hot air heater, in which a hot air outlet 3 at the lower front of the main body casing 1 blows out hot air forward.
On the other hand, inside the casing 1, devices such as a fan 3 and a heat exchanger 4 are housed.

This hot air heater is, for example, 4
The air drawn in from the room is heated by the heat exchanger 4 with hot water of 5°C or more, and the hot air is heated to 40°C or more, which is then output to the hot air outlet 2.
The fan coil unit that directs air from the air into the room uses a downward blowing method.

5 is a sensing object such as an antenna that can detect the state of the electric field at the relevant position in the air, and when a wind shielding object such as a human body approaches or comes into contact with it, it is possible to detect the capacitance possessed by the object. With such a structure, the detection body 5 includes a peripheral frame portion of the hot air outlet 2 and is disposed at a predetermined position near the hot air outlet 2.

In the illustrated example, the front plate of the casing 1 is attached to an insulating outlet grill provided at the hot air outlet 2.

This detector 5 is used to automatically stop the warm air heater, and is incorporated into the operating circuit shown in FIGS. 2 and 3.

The above operating circuit will first be explained with reference to those shown in Figure 2: rectifier section A, first oscillation circuit section C, constant voltage circuit section C, second oscillation circuit section II, AC amplifier section E, and output circuit. Each circuit section has the following functions.

The rectifier part A is for supplying DC low voltage power to the first oscillation circuit part, the constant voltage circuit part C, and the output circuit part. and turns transistor Q1 ON-OFF at every fixed cycle.
The system is activated repeatedly, and is formed into a monitoring circuit to periodically determine the presence or absence of wind shields.

On the other hand, the constant voltage circuit section C is for supplying a constant value of DC voltage to the second oscillation circuit section 2 and the AC amplifier section E, and the second oscillation circuit section 2 connects the sensing body 5 to the input terminal. The output (oscillation frequency) depends on whether the wind shield is in contact with, close to, or far away from the sensing object 5.
is formed so as to change, and this output is given as an input command to the AC amplifier section E.

Next, the AC amplification section E receives the output of the second oscillation circuit section 2, and if there is a change in the output, amplifies the change, and then supplies it as a base potential to the transistor Q2 to drive the output circuit section. The circuit is configured to send a stop command.

Further, the output circuit section has a configuration in which a pulse transistor 8 is connected in series to a circuit in which a coil 6 of an electromagnetic relay and a light emitting diode 7 are connected in parallel. When the transistor Q2 is in the OFF state, it is turned ON to excite the electromagnetic relay coil 6 and cause the light emitting diode 7 to emit light, thereby indicating the state with light emission when the heating function is stopped, for example, when the fan is stopped. .

As is clear from the circuit structure described above, in the circuit shown in the second figure, when the detection body 5 detects that the wind shield is close to the hot air outlet 2, the output of the second oscillation circuit section 2 changes, and this change occurs. amplified by the AC amplification section E.

This turns on the transistor Q2, triggering the pulse transistor 8, and the excitation of the coil 6 energizes the electromagnetic relay, which opens its normally closed contact to stop the heating function, and at the same time, indicates this by the light emission of the light emitting diode 7. .

When the closeness of the wind shield is released, the change in the output of the second oscillation circuit section 2 disappears, so the oscillation transistor 8 and the trigger signal disappear, and the oscillation transistor 8 and the trigger signal are turned 0N-OFF every certain cycle.
The electromagnetic relay is released from the ON state when the transistor Q1, which is repeatedly activated, is turned ON, so that the heating function is restarted automatically or when an operation command is given.

Next, to explain the circuit shown in the third country, this circuit includes a rectifier part I for supplying constant DC voltage to each circuit described later.
A DC amplifier having a sensing element 5 at its input terminal, a room temperature detection thermistor 9, a temperature setting device 10, a transistor Q4, and a light emitting diode 11 are connected to an output circuit section that operates to stop the heating function by demagnetizing the coil 6 of the relay. The sensor body 5 is composed of a one-step thermoelectric circuit with a bridge circuit at the input end, and when a wind shielding object such as a human body to be detected comes into contact with it, it converts the induced voltage generated by the capacitance it has into a direct current. The detector 5 is arranged in front of the hot air outlet 2 and connected to the outlet 2 or the high temperature section of the front surface of the casing.

On the other hand, the one-step thermo circuit section 1 operates to make the output transistor Q5 conductive when the room temperature detected by the thermistor 9 is lower than the set value, and rendered non-conductive when the temperature is higher.

The operation of this circuit is as follows.

That is, when a wind shield such as a human body touches the sensing body 5, the induced voltage generated by the wind shield is rectified and smoothed by the diode D3 and the capacitor C2, and then input to the DC amplifier.

As a result, an output of H level is output from the DC amplifier, so the transistor Q4 becomes conductive, causing the light emitting diode 11 to emit light, and at the same time, the input level of the one-step thermo circuit rises to H, making the output transistor Q5 non-conductive. Let it be.

Therefore, since the coil 6 is demagnetized and the output relay is deenergized, the heating function is stopped.

When the wind shield is no longer in contact with the sensing body 5, the transistor Q4 becomes non-conductive, and the one-step thermo circuit section 4 is automatically turned on/off depending on the level of the room temperature value detected by the thermistor 9.

As is clear from the operation mode of both sides described above, in the present invention, when the sensing body 5 capacitively detects the state in which the wind shield is in contact with or close to the hot air outlet 2, the fan coil unit during temperature adjustment operation is activated. For example, it is possible to issue a stop command to stop the fan motor and automatically interrupt the blowing of hot air, ensuring safety without causing burns in the case of a human body approaching, and in case of the approach of another object. By taking appropriate measures such as repositioning, unexpected accidents can be prevented.

In addition to stopping only the fan with a stop command, various other methods can be used, such as stopping the combustion operation as well in the case of a combustion hot-air fan, or stopping the operation completely regardless of the model. Several means of stopping are possible.

As described above, the present invention has a configuration in which the heating function is stopped by the detection body 5 when a wind shielding object comes into contact with or approaches the hot air outlet 2. Therefore, the heating function is stopped by the detection body 5. Unlike conventional devices that relied on passive safety maintenance, this system actively strives to improve safety, making it significantly different in terms of reliability and increasing the popularity of hot air heaters. It is highly effective in promoting the

Moreover, since it is only necessary to attach a detection body 5 such as an antenna and make some modifications to the control circuit, the cost required for the safety device is low, and it can also be easily applied to existing heaters. This invention has immeasurable economic advantages and is a great safety device for hot air heaters that will benefit the industry.

[Brief explanation of the drawing]

FIG. 1 is a side view of a heater according to an embodiment of the present invention, and FIGS. 2 and 3 are electrical control circuit diagrams. 1... Body casing, 2... Warm air outlet, 5... Sensing object.

Claims (1)

[Scope of utility model registration request] When a wind shield such as a human body comes into contact with or is in the vicinity,
A sensing body 5 capable of detecting the capacitance possessed by the human body and emitting a signal is disposed at or near the hot air outlet 2 of the main body casing 1, and the heating function is automatically activated upon receiving the signal from the sensing body 5. A safety device for a hot-air heater, characterized by having a circuit for stopping the warm-air heater.