JPS5850203Y2 - Hot air generator - Google Patents

Description

[Detailed description of the invention] This invention automatically adjusts the air flow rate to a heating element made of a positive temperature coefficient thermistor using a damper linked to the displacement of a bimetal, and controls the amount of heat generated to adjust the temperature. This relates to a wind generator.

BACKGROUND ART Conventionally, there has been a hot air generator as shown in FIG. 4, for example, as described in Denshi Gijutsu Vol. 19, No. 2.

In this figure, 21 is a main body case, and an air inlet 22 is provided on one side of the main body case, and an air outlet 23 is provided on the opposite side.

24 is a casing for forming an air passage between the suction port 22 and the air outlet 23; 25 is a filter provided in the air passage near the suction port 22; and 26 is a casing for forming an air flow. A blower 27 is a heating element made of a positive temperature coefficient thermistor having a honeycomb-shaped cavity provided in the air passage and near the blower outlet 23; 28 is provided between the heating element 27 and the blower 26; A damper is used to adjust the amount of air flowing to the heating element 27, and the rotary shaft 29 is rotated by an adjustment knob (not shown), so that its angle can be continuously changed.

In the hot air generator configured as described above, when the blower 26 is rotated and a current is applied to the heating element 27, air is sucked through the suction port 22, dust is removed by the filter 25, and the air is passed through the damper 28 to the heating element 27. When the air passes through the air, it is heated and hot air is blown out from the air outlet 23.

At this time, the angle of the damper 28 is manually changed so that the heating element 27
By changing the amount of air flowing through the heating element 27, the amount of heat generated by the heating element 27 will also change, making it possible to adjust the temperature.

However, in such a hot air generator, although the calorific value P(W) of the heating element 27 varies greatly depending on the amount of air Q (m3/m1n) passing through the heating element 27, as shown in an example in FIG. It only changes slightly depending on the temperature T1.

For example, when the air flow rate Q is 0.31T13/min and the suction air temperature T1 is 20°C, the calorific value P (W) of the heating element 27 is approximately 300W from FIG. 5, and the suction air temperature T1 is 40°C.
℃, the calorific value P of the heating element 27 is 2 from Fig. 5.
It becomes 80W, and the amount of heat generated P decreases only slightly.

In order to greatly change the calorific value P of the heating element 27 according to changes in the intake air temperature T1 in this hot air generator, manually operate the adjustment knob and rotate the damper 28 about the rotation shaft 29 to 27 must be varied.

In other words, when the ambient temperature changes significantly, the adjustment knob must be manually operated in order to significantly change the amount of heat generated.

Also, use the hot air generator described above in a narrow closed space, such as a Yagura kotatsu, and turn on the hot air supply device in an atmosphere of 20°C.
In this case, the air temperature inside the Yagura Kotatsu will have a calorific value P of 30
0.3m3/mi heated by 0W heating element 27
The air inside the tower is mixed and warmed by the n air.

Then, the air temperature inside the tower gradually rises, and the temperature T1 of the intake air of the hot air heating device also gradually rises, so that although the calorific value P gradually decreases as shown in FIG. 6, its change is small.

Therefore, the air temperature inside the tower increases rapidly, so in order to use this hot air generator as a tower kotatsu, a temperature sensor is used to detect the air temperature inside the tower, and when the temperature exceeds a predetermined temperature, electricity is turned on to the blower of the heating element. There is no choice but to take control to stop it.

In addition, among the heating devices often used in ordinary homes, infrared kotatsu, which heat small closed spaces, are equipped with a thermostat for temperature control. The temperature inside the kotatsu is adjusted by changing to a small amount of electricity and repeating this process repeatedly.

This method has the disadvantage that the temperature inside the kotatsu varies greatly, making the person trying to warm themselves uncomfortable.

Also, the thermostat etc. that adjust the temperature mentioned above is turned on and off.
During FF, radio wave interference occurs, causing noise on televisions, radios, etc.

Additionally, if a temperature regulator such as a thermostat malfunctions, the temperature inside the kotatsu may become abnormally high, potentially leading to a fire.

The purpose of this invention is to eliminate the drawbacks of conventional hot air generators,
It is a damper that can be used regardless of the volume of the space, whether it is open or a relatively narrow closed space, and controls the air flow rate to the heating element made of a positive temperature coefficient thermistor in response to the temperature of the air to be heated. To solve the above-mentioned drawbacks by quickly raising the temperature of the heated air and by smoothly, reliably, and safely controlling the temperature, and by constantly mixing the heated air and the heated air to prevent blowing out of high-temperature air. It is intended for that purpose.

That is, the configuration of the present invention is that a heating element made of a positive temperature coefficient thermistor is disposed in the air flow passage of the blower, and the air flow in the air flow passage is arranged in the air flow passage upstream of the heating element according to the temperature of the air to be heated. A damper device that controls the flow rate is provided to change the amount of heat generated by the heating element according to changes in the air flow rate, while an exhaust port that is opened and closed by the damper is provided to prevent this even when the amount of air to the heating element is maximized. Provide a specified gap at the exhaust port,
This hot air generator is configured to blow out a mixture of exhaust air and air heated by the heating element from this exhaust port.

First, the positive temperature coefficient thermistor receives a heat dissipation effect due to the passage of a large amount of air, so that the temperature does not rise, so due to its characteristics, the amount of heat generated is large.

Then, when the air temperature gradually increases, the damper is displaced in a direction to close the air flow path to the PTC thermistor, reducing the amount of air flowing to the PTC thermistor, and reducing the amount of heat generated by the PTC thermistor.

When the heated air reaches a predetermined temperature, the damper closes the air flow path to the PTC thermistor, and the amount of heat generated by the PTC thermistor becomes extremely small.

In addition, even when the amount of air to the positive temperature coefficient thermistor is maximized, the damper exhausts a predetermined amount of air from the exhaust port, so this exhaust air is mixed with air heated by the heating element, resulting in high-temperature air that makes people feel uncomfortable. Prevent speech bubbles.

As mentioned above, the temperature of the heated air is quickly raised,
In addition, the temperature of the blown air is maintained at an appropriate temperature.

The present invention will be described below with reference to an embodiment in which the present invention is incorporated into a Yagura Kotatsu as an example of a heater.

In FIG. 1, 1 is a tower, and 2 is a hot air generator installed under the top of the tower.

FIG. 2 is a longitudinal cross-sectional view of the warm air generator 2, in which 3 is the main body case, 4 is an airflow generation fan, 5 is a motor for driving this airflow generation fan 4, and 6 is for this drive. A motor fixing plate is attached to the main body case 3 via a plurality of anti-vibration rubbers 7 for fixing the motor, 8 is a fan casing which forms a fan outlet 9 together with the motor fixing plate, and 10 is the fan outlet. A blowout duct 11 forms a part of the air flow passage from the opening 9, and 11 is a heating element made of a positive temperature coefficient thermistor provided in this blowout duct, and this has a large number of circular, rectangular, polygonal, etc. ventilation holes. What will happen,
Alternatively, it is constructed by arranging a large number of flat plate-shaped, disk-shaped, etc. heating elements in an air flow, and one or more of these heating elements are provided.

This heating element consists of a positive characteristic thermistor, so if the air flow rate passing through the heating element increases, the amount of heat generated will increase in proportion to it, and if the air flow rate decreases, the amount of heat generated will also decrease, and when the air flow rate becomes extremely small. , the amount of heat generated is also extremely small.

12 is an exhaust port provided in a removable intermediate duct 13 formed between the fan outlet 9 and the air outlet duct 10; 14 is an exhaust port 12 for diverting the air flow rate generated by the fan 4; By doing so, the damper 15 automatically adjusts the air flow rate to the heating element 11, and mixes the airflow exhausted from the exhaust port 12 with the airflow blown out after passing through the heating element 11. Daku)
A mixing chamber 16 is formed by a part of the wall surface of 10, and a mixing duct communicates with a main body outlet 17 provided in the main body case 3. Reference numeral 18 is a suction port provided in the main body case 3.

FIG. 3 is an enlarged perspective view of the intermediate duct 13, with parts of the damper 14 and the exhaust port 12 cut away to show its structure in detail.

In this figure, 20 is a spiral-shaped bimetal whose outer peripheral end is fixed by a fixed shaft 23 and whose center is connected to the damper by a rotating shaft 21, which is displaced in proportion to the temperature of the inflowing air.
When the temperature exceeds a predetermined temperature, a rotational force is applied to the rotating shaft 21 to rotate the damper 14 about the fulcrum in the direction in which the exhaust port 12 opens.

22 is the exhaust port 12 even at a temperature below the first predetermined temperature.
This is a restraining plate provided on the intermediate duct 13 that restrains the damper 14 with a predetermined gap between the damper 14 and the damper 14 .

In the warm air electric kotatsu constructed as above,
At the start, the temperature inside the kotatsu is still low and the bimetal 20 is not deformed, so the damper 14 remains in close contact with the restraining plate. Therefore, the predetermined amount of air flow is always exhausted from the exhaust port and passes through the heating element 11. The flow rate of the air blown out is at its maximum, and at this time the heat generation amount of the heating element 11 is at its maximum, the temperature inside the kotatsu rises quickly, and since the air is forced, the temperature inside the kotatsu is also uniform.

When the temperature inside the kotatsu exceeds a first predetermined temperature, the damper 14 rotates in proportion to the temperature in response to the displacement of the bimetal 20 in the direction of opening the exhaust port 12, and the flow rate of air exhausted from the exhaust port 12 is Conversely, the flow rate of air blown out through the heating element 11 decreases.

Both air flows are mixed in the mixing chamber 16 and the air flows through the main body outlet 17.
More blown out.

The amount of heat generated by the heating element 11 also decreases in proportion to the flow rate of air passing through it.

When the temperature rises to a second predetermined temperature, the damper 14 is positioned at a predetermined angle with respect to the fan outlet, closes the intermediate duct 13, minimizes the air flow to the heating element 11, and exhausts air from the exhaust port 12. The maximum air flow rate is blown out from the main body outlet 17 via the mixing chamber 16.

In this state, the amount of air passing through the heating element 11 is extremely small, so the amount of heat generated is extremely small.

When the temperature of the kotatsu falls, the damper 14 rotates in a direction to close the exhaust port 12, the flow rate of air passing through the heating element 11 increases, and the amount of heat generated increases.

However, since the heating element 11 is a positive temperature coefficient thermistor and is designed so that the flow rate of air passing through the heating element 11 decreases when the temperature increases, the heating element itself does not generate abnormal heat and is safe.

Also, even if the temperature inside the kotatsu drops due to people coming and going,
Accordingly, the damper 14 adjusts the air flow upward and automatically increases the amount of heat generated, so that the temperature inside the kotatsu is always kept constant.

Further, since the predetermined flow rate of air that does not pass through the heating element is always mixed with the high temperature air flow rate that has passed through the heating element in the mixing chamber and blown out, the temperature of the blown air becomes an appropriate temperature.

Additionally, because the amount of heat generated is continuously and automatically adjusted, the temperature change inside the kotatsu is smaller than with conventional infrared kotatsu, and does not cause discomfort to the person trying to stay warm.

Moreover, the amount of heat generated by the kotatsu is designed based on the air flow rate that passes through the heating element, and the fan drive motor is cooled because the air flow rate and the predetermined air flow rate that is constantly exhausted from the exhaust port pass through the fan drive motor. It is highly effective, the amount of air generated by the fan is always constant, and the design takes into account factors such as longevity.

Furthermore, since it does not have a temperature controller such as a thermostat that can be turned on and off, there is no radio wave interference to televisions, radios, etc. that occurs with conventional infrared kotatsu.

In the above embodiment, a restraint plate is provided inside the duct I-, but this restraint plate is provided at a predetermined position of the damper or near the rotation axis of the damper.

Alternatively, the structure may be such that a predetermined amount of air is always exhausted from the exhaust port even when the temperature is below the first predetermined temperature, such as when a part of the damper shape is smaller than the exhaust port shape, and the damper is driven by a spiral-shaped bimetal. There are many methods, including but not limited to, configuring the damper itself with bimetal.

By the way, in the above description, the present invention was explained in the case of an electric kotatsu, but it goes without saying that it can also be used in other heaters and heat insulators.

Moreover, if the damper has this configuration, the machining accuracy is not strictly required and it becomes simple.

As explained above, in this invention, air is supplied to the heating element of a PTC thermistor by forced air flow, so that the temperature rises well and uniformly.Moreover, a constant flow rate of air is always released without passing through the heating element, so the heating element is It softens the temperature of the airflow that passes through it and blows out air at an appropriate temperature, resulting in better comfort, and compared to a structure in which all the airflow generated by a fan passes through to the heating element, the structure is better. It is characterized by being simple, and because the air flow rate is automatically adjusted by the damper, there is little temperature change and no radio wave interference occurs.

[Brief explanation of drawings]

The figures show one embodiment of the present invention. Figure 1 is a vertical cross-sectional view of the device installed in a tower kotatsu, Figure 2 is an enlarged vertical cross-sectional view of the device, and Figure 3 is a damper installed. FIG. 4 is a vertical cross-sectional view of a conventional hot air generator; FIG. 5 is a characteristic diagram showing the amount of air passing through a heating element consisting of an hourly thermistor and the amount of heat generated; FIG. 6 is a characteristic diagram of the temperature and calorific value of the kotatsu over time when a conventional hot air generator is installed in the kotatsu. In the figure, 4 is a fan, 8 is a casing, 10 is a blowout duct, 11 is a heating element, 12 is an exhaust port, 13 is an intermediate duct, 14 is a damper, 20 is a bimetal, and 22 is a restraint plate. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] An air flow path that incorporates a fan for generating air flow and a positive temperature coefficient thermistor as a heating element, an exhaust port provided between the fan and the heat generating element of this air flow path, and an air flow path that is displaced according to the temperature of the incoming air. , by changing the air flow rate to this exhaust port, the air flow rate to the heating element is automatically adjusted, and even when the temperature is below a predetermined temperature, a predetermined gap is provided between the air outlet and the exhaust port so that the predetermined air flow rate is always maintained between the exhaust port and the exhaust port. 1. A hot air generator comprising: a damper for ejecting air to the heating element; and a structure for blowing out a mixture of air heated by the heating element and exhaust air from the exhaust port.