JPS6125561Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a hot air device having a heat source using a combination of a resistance heating element such as Ni-Cr and a positive temperature coefficient thermistor.

Conventionally, in hot air equipment that uses resistance heating elements such as Ni-Cr as heaters, when changing the air temperature, it is necessary to change the number of installed resistance heating elements, change the capacity with an intermediate tap, or change the air volume (air volume). A method is used to change the amount by adjusting it with a damper or the like.

On the other hand, in order to switch the discharge air temperature of a hot air device using a positive temperature coefficient thermistor, it is possible to change the number of units installed, adjust the amount of air passing inside the positive coefficient thermistor with a damper, or change the mixing ratio with cold air. The discharge air temperature was changed by a method such as

Figures 1 and 2 show an example of this state, and show an air blower (hereinafter referred to as a fan) in the hot air device 1.
2 is used to send the air to the positive characteristic thermistor 3 in the direction of the arrow, and the damper 4 adjusts the passing air volume or supply air volume to switch the discharge air temperature.

However, with such conventional devices, the wiring is complicated, the load on the fan motor is large, the lifespan is short, and the air is only sent in one direction.
Problems such as clogging occurred due to adhesion of dust to the positive temperature coefficient thermistor 3.

This invention was made to eliminate the above-mentioned drawbacks, and even in a hot air mechanism that uses both a positive temperature coefficient thermistor and a resistance heating element as heat sources, by reversing the direction of air flow, It is an object of the present invention to provide a hot air device in which the positional relationship between a positive temperature coefficient thermistor and a resistance heating element with respect to the air flow path is reversed, and the temperature of the hot air is adjusted by the resulting change in the amount of heat generated by the positive temperature coefficient thermistor.

Due to its characteristics, when a positive temperature coefficient thermistor is used as a heat source of a hot air device, its calorific value changes as shown in FIG. 3 in accordance with the intake air temperature of the incoming air. However, it is known that in a resistance heating element, the amount of heat generated does not change even if the intake hot air changes.

This idea incorporates the phenomenon shown in Figure 3 and the general properties of resistance heating elements into a hot air device that uses both a positive temperature coefficient thermistor and a resistance heating element, and changes the flow path of the air to increase the temperature. The basic idea is to adjust the temperature of the air discharged from the wind device.

To explain specifically based on Figures 4 and 5,
Figure 4 shows an electric circuit in which a positive temperature coefficient thermistor 3 and a resistance heating element 5 are connected in series.For example, if the wind direction is direction A, the flow of air passes through the positive temperature coefficient thermistor 3 as shown by the arrow and the resistance heating element 5. Sent to 5. In this case, the cold air passes through the PTC thermistor 3 and the amount of heat generated by the PTC thermistor 3 becomes larger, so that the temperature of the discharged air can be increased.

Conversely, when the wind direction is set to direction B, the air flow passes through the resistance heating element 5 as shown by the arrow and the warm air is sent to the positive temperature coefficient thermistor 3, so the amount of heat generated by the positive temperature coefficient thermistor 3 is not very large. First, the discharge air temperature can be lowered.

FIG. 5 shows an electric circuit in which a positive temperature coefficient thermistor 3 and a resistance heating element 5 are connected in parallel.

In this case as well, it is shown that the air temperature can be adjusted simply by changing the air direction, similar to the embodiment explained in FIG. 4.

Next, a feature of this invention in which the direction of the wind is reversed will be explained.

FIG. 6 shows an embodiment of the hot air device according to this invention, in which the rotation of the fan 2 of the hot air device 1 is reversed depending on the purpose, and adjustment is made to discharge the desired hot air according to the above-mentioned principle. It is.

In this embodiment, when hot air is discharged from A to B, the fan 2 sucks in the hot air sent from the A direction and discharges it to B.
When sending and discharging hot air from A to A, the principle explained in FIGS. 4 and 5 is applied as is, and desired hot air can be discharged.

FIG. 7 also shows an embodiment of the hot air device according to this invention, in which the air flow path is reversed according to the purpose using slide ducts 6, 6 to adjust the discharge air temperature.

Figure 7A shows the state when the slide duct 6 of the warm air device 1 is slid to the left, and the air sent from the fan 2 is aligned with the slide duct 6 and each ventilation hole 6a, 7a of the air passage 7. As a result, the air passes through the air passageway, passes through the positive temperature coefficient thermistor 3 and the resistance heating element 5, and is discharged as shown by the arrow.

Figure B shows the state when the slide duct 6 of the warm air device is slid to the right, and the air sent from the fan 2 is aligned with the slide duct 6 and the other ventilation holes 6b and 7b of the air passage 7. By doing so,
It passes through and is guided into the air duct, then passes through a resistance heating element 5 and a positive temperature coefficient thermistor 3 in that order, and is discharged in the direction of the arrow, and the temperature of the discharged air can be adjusted from these operations.

As detailed above, according to the hot air device of this invention, there is no need to perform complicated operations such as adjusting the air flow rate or switching the number of energized heat sources.
Desired air temperature can be adjusted with a simple device. Even when the rotation of the fan of the hot air device is reversed, there is no need for accessory devices for adjusting the air volume, such as dampers or bypasses, which is economical. Even if dust or the like adheres to the heat source of the hot air device, it can be removed when the wind direction is reversed, eliminating problems such as a decrease in heat output or overheating due to clogging of the heat source. There are advantages such as

[Brief explanation of the drawing]

Figures 1 and 2 are schematic diagrams of conventional hot air equipment, Figure 3 is a diagram of the relationship between intake air temperature and calorific value according to this invention, and Figure 4 is a series connection of a positive temperature coefficient thermistor and a resistance heating element. An electric circuit diagram, FIG. 5 is a parallel connection electric circuit diagram, FIG. 6 is an embodiment diagram of this invention, and FIG. 7 is another embodiment of this invention.
A is a state diagram when the slide duct is moved to the left, and B is a state diagram when it is similarly moved to the right. DESCRIPTION OF SYMBOLS 1... Warm air device, 2... Fan, 3... Positive characteristic thermistor, 4... Damper, 5... Resistance heating element, 6... Slide duct, 6a, 6b... Ventilation hole of slide duct, 7... ...Wind path, 7a, 7b...
...Air vents.

Claims (1)

[Claims for Utility Model Registration] (1) In a hot air device that is equipped with an air blower and uses a positive temperature coefficient thermistor and a resistance heating element as a heat source, the direction of flow of air in the hot air device is reversed. A hot air device characterized by being equipped with a reversible device that adjusts air temperature. (2) The hot air device according to claim 1, wherein the direction of flow of air in the hot air device is reversed by a blower. (3) The hot air device according to claim 1, wherein the direction of flow of air in the hot air device is reversed by a slide duct.