JPH0711682Y2 - Hair dryer voltage switching device - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is to automatically switch the connection state of a plurality of heaters according to the supplied AC power supply voltage.

[0002]

2. Description of the Related Art Recently, the number of overseas travelers has increased, and a hair dryer has become an essential item during this trip.

However, the supplied AC voltage varies from country to country, and there is a drawback that the hair dryer carried cannot be used as it is. Therefore, since the voltage of each country in the world is roughly divided into 100V and 200V, a switch which is attached to the main body of the hair dryer and which switches the switch according to the supplied voltage has been commercialized. Such specific prior art is disclosed in Japanese Utility Model Publication No. 58-18804 filed by the same applicant.

However, in the above-mentioned prior art, since the voltage supplied in advance is confirmed and the changeover switch is manually operated to switch the heater according to the voltage, the hair dryer. Before connecting the main unit to the outlet, it is necessary to check the supplied voltage, which is troublesome, and if the operation is forgotten or the switch is mistakenly made, the heater will be burnt out or an abnormal overheat will occur. There was a risk of fire.

The drive power source for the motor that rotates the fan is generally a DC low voltage (12V or 24V).
For example, if the AC power supply for obtaining this DC low voltage does not have a perfect sine waveform, there are drawbacks that sparks are generated on the electrodes of the motor, the life of the motor is shortened, and smooth rotation is not possible.

As a specific example of this, since a heater connected to a diode for obtaining a direct current drive power source for a motor is connected and disconnected by opening and closing an element with a control pole such as an SCR or a triac, the heater is supplied to this heater. A spark is generated because the power supply waveform is not a perfect sine waveform due to the firing angle.

[0007]

In the present invention, the heater circuit is automatically switched by the triac and the relay switch according to the supplied power voltage, and the life of the motor is extended regardless of the switching circuit. It is a thing.

[0008]

According to the present invention, there is provided a heater unit having a first heater and a second heater, a voltage switching circuit for changing a connection state of the heater according to a supplied AC power supply voltage, and a voltage switching circuit. A relay switch that connects or disconnects the first heater and the second heater in series according to the output, a triac that is connected in series to the second heater and is turned on by the output of the voltage switching circuit, and is converted to direct current by a diode. When the AC power supplied is low, the triac is turned on to connect the series circuit of the triac and the second heater in parallel to the first heater, When the voltage is at a voltage, the triac is turned off, and the first heater and the second heater are connected in series by a relay switch. Over de is a structure in which to obtain a power for driving a motor connected to the first heater.

[0009]

When the supplied AC power source has a low voltage, the triac is turned on and the first heater and the second heater are connected in parallel with the relay switch not operating. When the supplied AC power source has a high voltage, the triac is turned off and the relay switch is operated to connect the first heater and the second heater in series. Regardless of whether the AC power supply is low voltage or high voltage, the first heater supplying the DC power supply for driving the motor receives a complete AC power supply sinusoidal waveform unrelated to the triac, so that the motor is driven by the motor. Does not generate sparks.

[0010]

Embodiments of the present invention will be described with reference to the drawings.
(1) has a discharge port (2) on the front surface and an intake port (3) on the rear surface
Is a bar-shaped hair dryer body having a grip portion (4) on the side of the intake port, and is formed by a bar-shaped cylindrical case (5) in which divided cases are combined. (6) is a heater unit disposed on the side of the discharge port (2) in the cylindrical case (5), which is a combination of insulating substrates (7) and (7) combined in a cross shape and the winding unit wound around the substrate. It has one heater (8), a second heater (9) and a limiter (10). (11) is a motor holder arranged between the heater unit (6) and the intake port (3) in the cylindrical case (5), and the motor (12) is fixed by this holder. A fan (13) is fixed to 12). (14) is a mounting board fixed to the end of the motor (12) near the heater unit (6) side, and is a capacitor (15), (1) for preventing noise of the motor (12).
5) and diodes (16) and (17) for turning the power applied to the motor to direct current and the triac (40) are attached. The outer diameter of the mounting substrate (14) is set to be the same as or slightly smaller than the outer diameter of the motor (12) in order to reduce the air passage resistance. Most of the triac (40) is made to project from the outer peripheral edge of the mounting substrate (14) so that the wind flowing on the outer wall of the motor (12) is cooled. Reference numeral (18) is a fixing screw for the mounting substrate (14).

Reference numeral (19) is a partition wall integrally provided on the inner wall of the cylindrical case (5), which forms a space (20) between the outer wall and the end wall (2) located on the motor (12) side.
1) is inclined toward the outer wall so that the wind is collected and the wind is forced to hit the triac (40).
Reference numeral (22) is a printed circuit board housed in the space (20), to which electronic parts are attached.

Next, the electric circuit diagram shown in FIG. 1 will be described. (24) and (24) are supply terminals of an AC power supply,
(25) is a voltage switching circuit for switching the heater circuit according to the power supply voltage supplied to the supply terminal, which will be described in detail below. (26) is an SCR, and (27) is a relay connected in series to the SCR, which operates a relay switch (28). This relay switch includes a movable contact (29) connected to the other end of the first heater (8), the triac (40) and a second contact.
One fixed contact (30) (normally open contact) connected to the other end of the heater (9) and the other fixed contact (31) (normally closed contact) connected to one end of the second heater (9) have.

(32) is the supply terminals (24), (2
Convert to DC with the diode connected to 4). (33),
(34) is the first and second voltage dividing resistors connected in series with each other and is connected to the DC power source, and (35) is the SCR (26).
Is a constant voltage element connected between the gate of and the connection portion of the first and second voltage dividing resistors (33) and (34). When the connection portion reaches a predetermined potential, it conducts to connect the SCR (26). Turn it on. A base (36) connects the base to a connection portion of the relay (27) and the SCR (26) through a bias resistor (37), and a collector of the first and second resistors (38), (39).
A switching element (hereinafter referred to as a transistor), which is connected to one of the supply terminals via the, and the emitter of which is connected to the anode of the diode (32) on the other side of the supply terminal. (3
7) is a bias resistor connected between the relay (27) and the base of the transistor (36); First and second connected between collectors
A resistor, (40), is a triac connected between one of the supply terminals (24) and the other end of the second heater (9) <one fixed contact (30)>, the gate of which is connected to the first resistor (38). It is connected to the connection portion of the second resistor (39). (41) is a step-down resistor, (42) is a smoothing capacitor, (43) is a relay (27) and SCR (26), and a transistor (3).
6) is a constant voltage diode that operates at a low voltage.

On the other hand, the diodes (16) and (17) are connected as a bridge circuit to a part of the first heater (8), and a DC voltage obtained by converting an AC power source obtained from both ends of the connection is applied to the motor (12). Connected.

The connection position of the diodes (16) and (17) is (100) when the voltage of the supplied AC power source is low.
V) or high (200 V), the heater is not related to the triac (40) (first heater)
Becomes

The operation will be described below. First, the case where low voltage AC100V of the supply terminals (24) and (24) is supplied will be described. In this case, since the potential of the connection portion of the voltage dividing resistors (33) and (34) is low and the constant voltage element (35) does not reach the Zener voltage, the SCR (2
6) is off. Since the SCR (26) is OFF, the relay (27) is not driven and the movable contact (29) of the relay switch (28) is connected to the other fixed contact (31) as shown by the solid line position in FIG. ing. On the other hand, the transistor (36) becomes conductive via the relay (27) and the bias resistor (37), and the triac (40) becomes O.
N. Therefore, the first heater (8) and the second heater (9) are arranged in parallel, and the supply terminals (24), (2
4), and 100 V is applied to each heater.

Next, the case where a high voltage AC200V is supplied to the supply terminals (24) and (24) will be described. In this case, the potential of the connection between the voltage dividing resistors (33) and (34) is high and reaches the Zener voltage of the constant voltage element (35), the constant voltage element becomes conductive, the SCR (26) is turned on, and the relay (27) is turned on. Is driven and the movable contact (29) of the relay switch (28) is connected to one fixed contact (30) as shown by the broken line position in FIG. On the other hand, the SCR (2
Since the transistor (36) is turned off in accordance with the turning on of 6), the triac (40) is turned off. Therefore, the first
The heater (8) and the second heater (9) are connected in series.

As described above, the DC power supply for the motor (12) is separated from the triac (40) side by the first heater regardless of whether the supplied AC power supply has a low voltage or a high voltage. It will be supplied from (8).

[0019]

As described above, according to the present invention, since the connection state of the first heater and the second heater is automatically switched by the supplied AC power supply voltage, before the hair dryer body is used as in the conventional case. There is no need to check the supplied power voltage. Since the switching of the heater circuit is performed by the two switches of the triac and the relay switch, the number of large components is reduced and the size of the circuit components is reduced as compared with the switching using two sets of relay switches.

In particular, the DC power for driving the motor is not supplied from the second heater connected to the triac side, but is supplied as a triac, regardless of whether the supplied AC power is low voltage or high voltage. Since it is supplied from the first heater that can obtain a complete AC power supply waveform independently of the above, sparks are not generated from the electrodes of the motor, and the life of the motor is shortened, noise is generated, and rotation becomes unstable. There is no.

[Brief description of drawings]

FIG. 1 shows an electric circuit of a voltage switching device of a hair dryer according to the present invention.

FIG. 2 is a partial sectional view of the same.

FIG. 3 is a perspective view showing a mounted state of the triac.

[Explanation of symbols]

 1 Hair Dryer Main Body 6 Heater Unit 8 First Heater 9 Second Heater 12 Motor 13 Fan 16 Diode 25 Voltage Switching Circuit 27 Relay 28 Relay Switch 40 Triac

Claims (1)

[Scope of utility model registration request] 1. A heater unit having a first heater and a second heater, a voltage switching circuit that changes a connection state of the heater according to a supplied AC power supply voltage, and the first heater and the first heater based on an output of the voltage switching circuit. A relay switch that connects or disconnects two heaters in series, a triac that is connected in series to the second heater and is turned on by the output of the voltage switching circuit, and a fan rotation driven by a voltage converted into direct current by a diode. When the supplied AC power source has a low voltage, the triac is turned on and the series circuit of the triac and the second heater is connected in parallel to the first heater, and when the voltage is high, the triac is turned off. In the case where the first heater and the second heater are connected in series by a relay switch, the diode is connected to the first heater. A voltage switching device for a hair dryer, which is characterized in that a power source for driving a motor is continuously obtained.