JPS6112181B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hot air heater, and in particular, when a wind shield comes into contact with hot air blown out, it can cause burns to the human body.
Another object of the present invention is to provide a safety device that can prevent damage to other objects due to 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 position as close as 10 cm, there is a risk of high-temperature burns.
Even if the temperature is low, if the model is exposed to hot air for a considerable period of time, low-temperature burns can occur.

Furthermore, even if it is not a human body, it is also undesirable to leave an object that is subject to thermal deformation due to rising temperature in close proximity to the hot air outlet.

However, with conventional heaters, the user's manual does not allow people to touch or get close to the hot air outlet, even though they are aware that it is dangerous if a person or other wind shield gets close to the hot air outlet. They only issued warnings to prevent this from happening, and no further rational measures were taken, such as proactively implementing measures such as using the equipment, resulting in low-temperature burns to young children and the elderly.
Situations such as heat deformation of instruments that are not heat resistant continue to occur, and it has been desired to provide some kind of safety device.

In view of these circumstances, the present invention promptly detects the occurrence of the various abnormal conditions described above, and automatically and proactively stops the heating function, such as by interrupting the heating operation, thereby providing various solutions. DESCRIPTION OF THE PREFERRED EMBODIMENTS An object of the present invention is to provide a novel safety device for hot-air heaters that can prevent accidents, and embodiments of the present invention will be specifically described below with reference to embodiments of the accompanying drawings.

FIG. 1 shows a floor-mounted hot air heater, in which a hot air outlet 2 for blowing out hot air forward is provided at the lower front of the main body casing 1;
Equipment such as a fan 3 and a heat exchanger 4 are housed inside.

This hot air heater heats the air drawn in from the room with a heat exchanger 4 using hot water of 45°C or higher sent from a hot water boiler, for example, and generates hot air with a temperature of 40°C or higher from a hot air outlet 2. It is formed into a fan coil unit that blows out air indoors using a downward blowing method.

Reference numerals 5 and 6 denote temperature measuring elements such as temperature sensors.The temperature measuring element 5 is attached to the hot air outlet 2, while the temperature measuring element 6 is attached to a predetermined position near the hot air outlet 2, and the temperature measuring element 6 is attached to a predetermined position near the hot air outlet 2. It is fixed with the hot side facing forward.

In the illustrated example, the temperature measuring element 6 is attached to the front plate of the casing 1 at a position below the hot air outlet 2 that does not come into direct contact with the hot air blown out.

In addition, in order to set the mounting location of the temperature sensor 6, it is necessary to satisfy the following conditions. That is, the wind shield 17 with a fairly large surface area, such as a person, should not approach or come into contact with the hot air outlet 2. This causes a change in the airflow of the blown hot air, and it is necessary to identify a position where the temperature can rise due to this airflow change.

However, in the above example, because the wind shield 17 is in close contact with or close to the hot air outlet 2, the hot air blows against the wind shield 17 and then turns around to cause the temperature measuring body to 6 or when the heat rays in the hot air are reflected by the wind shield 17 and radiate to the temperature sensor 6, the temperature sensor 6 senses the temperature rise. Needless to say, a corresponding control signal is emitted from the temperature measuring body 6.

The temperature measuring elements 5 and 6 are used to automatically stop the warm air heater, and are incorporated into the operating circuit shown in FIG. 2.

The above operation circuit includes rectifier part A, hot water temperature thermostat 7
A cold air prevention circuit section (b) having a room temperature thermometer 8 as a detection element, a temperature adjustment circuit section (c) having a room temperature thermometer 8 as a detection element, a temperature difference detection circuit section (d) having a temperature measuring body 5, 6 as a detection element, a temperature difference detection prohibition timer (e), an automatic It consists of seven circuit sections, including a return timer and an output circuit section, and each circuit section functions as follows.

The rectifier part (a) is for supplying DC low voltage power to each part rot. , an amplifier 9, a transistor Q ₁ , and a light emitting diode 10. When the hot water reaches a set temperature, for example, 40°C or less, the amplifier 9 generates an output voltage to make the transistor Q ₁ conductive, and the temperature control circuit of the next stage is activated. It operates so as to lower the potential at the input terminal of part C and cause the light emitting diode 10 to emit light to notify that the operation has stopped in a cold air condition.

On the other hand, the temperature adjustment circuit section C is the temperature setting resistor 1.
1, a room temperature thermostat 8, an amplifier 12, and a transistor _Q2 , and when the transistor _Q1 is non-conducting, that is, when the hot water temperature is higher than the set temperature, the room temperature is, for example, 15 to 30°C. When the temperature is above the set temperature within the range of °C, transistor _Q2 is made non-conductive, and when the temperature is below the set temperature, transistor _Q2 is made conductive, and the subsequent output circuit section is deactivated and activated. .

Next, the temperature difference detection circuit section D is a main part of the present invention, and includes the temperature measuring elements 5 and 6 and the amplifier 13.
and a light emitting diode 14, and the thermometer 5 detects the temperature of the hot air at the outlet 2, for example 60°C, while the thermometer 6 detects the temperature of the warm air at 60°C as the wind shield 17 approaches.
When it is detected that the temperature has become higher than the predetermined temperature of approximately 45°C, the difference between the two temperatures becomes less than the set value of 15°C, so the output e of the amplifier 12 is changed to L, and the diode 15 By drifting the base potential of the transistor Q ₂ to the grounded state through the transistor Q 2 , the transistor Q ₂ is forcibly rendered non-conductive, and the light emitting diode 14 is caused to emit light to notify the operation of the temperature difference detection circuit section 2. On the other hand, when the temperature sensing element 6 detects a state where the temperature is below a predetermined temperature, that is, a normal state, the output e of the amplifier 13 is changed to H, the forced non-conduction of the transistor Q ₂ is released, and the light emitting diode 14 is turned off. When the temperature difference detection circuit section 2 is turned off, the non-operation of the temperature difference detection circuit section 2 is notified. Reference numeral 18 denotes a temperature difference setting resistor, which is formed so that the set value of the temperature difference can be made variable by making the resistance variable.

Next, the temperature difference detection prohibition timer is a circuit that prevents a false stop signal from being issued from the temperature difference detection circuit section 2 when there is no temperature difference between the temperature measuring elements 5 and 6 immediately after the start of operation. At the same time as the temperature control circuit part C emits the H output, it measures the time and holds the output of the amplifier 13 at H until the time limit, for example, about 15 seconds, at which temperature difference can be detected by the temperature measuring elements 5 and 6 has elapsed. A command is issued, the command is then erased, and the automatic reset timer is reset by a release command to be described later.

In addition, the automatic reset timer measures time in response to the start of operation of the temperature difference detection circuit section 2, and when a predetermined time limit of about 5 minutes has elapsed, a release command is issued to the amplifier 13 to stop the operation of the temperature difference detection circuit section 2. An automatic reset circuit is formed to force a return.

Note that the present invention may be capable of not only automatic recovery but also manual reset.

Next, to the output circuit section, the coil 16 of the electromagnetic relay for the fan is connected to the power supply through the transistor Q ₂ in series, and is excited by the conduction of the transistor Q ₂ and energizes the fan motor. The fan motor is deenergized by demagnetization due to non-conduction of the transistor _Q2 .

As is clear from the above circuit description, the present invention is configured such that when the temperature measuring elements 5 and 6 detect the state in which the wind shield 17 is close to the hot air outlet 2 using a temperature difference signal, the fan coil unit during temperature adjustment operation is activated. By issuing a stop command to the device, in other words, forcibly making transistor _Q2 non-conductive, it is possible to stop the fan motor and automatically interrupt the hot air blowout, which can prevent burns in the case of close contact with a human body. Safety can be maintained without any danger, and unexpected accidents can be prevented by taking appropriate measures such as changing the position in the event of another object approaching.

In addition to stopping only the fan with a stop command, in the case of a combustion-type hot-air fan, the combustion operation may also be stopped, or the operation may be completely stopped regardless of the model. Various stopping means are possible.

Further, the present invention is characterized in that the temperature measuring element 6 detects the temperature at a predetermined position and compares it with the temperature at the outlet. It is mainly capable of detecting whether or not the object is approaching a position where the temperature will result in It can be demonstrated.

The temperature measuring element 5 may be installed in the hot air blowing passage as in the embodiment, or in a fan coil type where it can detect the hot water inlet or outlet temperature, or in a combustion type in a position where it can detect the temperature at the inlet or outlet of the hot water. It may be a position where the surface temperature of the heat exchanger can be detected.In short, it may be a position that is related to the heat source, and may be determined depending on the installation position of both temperature sensors 5 and 6 and the size and position of the wind shield 17. The set value of the temperature difference is determined experimentally in advance.

Furthermore, if the present invention is applied to a bottom-blowing hot air heater as in the embodiment, the heating effect is good, and the temperature remains low even when infants, elderly people, etc. are lying on the floor near the hot air outlet. This has the effect of killing two birds with one stone, as there is no need to worry about getting burned.

As is clear from the above explanation, the safety device of the present invention is designed to protect the body from the temperature at a location related to the heat source of the heater, and at a location near the hot air outlet 2 and a wind shield 1 such as a person.
Temperature measuring elements 5 and 6 are respectively disposed at positions where the temperature increases due to airflow changes of hot air blown out due to the approach of temperature sensing elements 5 and 6, and the difference in temperature detected by both temperature measuring elements 5 and 6 is determined. Because we have installed a circuit that automatically stops the heating function when the signal value corresponding to the Since the system is actively working to improve safety, it is significantly different in terms of reliability and will have a great effect on promoting the spread of warm air heaters.

Moreover, the cost required for the safety device is low, as it is only necessary to attach temperature measuring elements 5 and 6 such as thermistors and make slight modifications to the control circuit, and furthermore, it can be easily applied to existing heaters. It is possible to do so, and the economic benefits are immeasurable.
The present invention is a safety device for hot air heaters that greatly benefits 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 FIG. 2 is an electric control circuit diagram. 1... Main body casing, 2... Warm air outlet, 5
...Thermometer, 6...Temperature sensor, 17...Wind shield.

Claims (1)

[Claims] 1 A place near the hot air outlet 2 of the main body casing 1 that is not directly hit by the hot air blowing out and a wind shield 17 for people etc.
Temperature measuring elements 6 and 5 are respectively disposed at a position where the temperature rises due to a change in the air flow of hot air blown out due to the approach of the heater, and at a position where the temperature is related to the heat source of the heater. A hot air type heater characterized in that it is provided with a circuit that automatically stops the heating function when the signal value corresponding to the difference in temperature detected by the temperature measuring elements 5 and 6 falls below a set value. Safety device.