JPH05328720A - Phase controller - Google Patents

Abstract

PURPOSE:To provide a phase controller, in which phase control for one load has no effect on that for the other load whether the environment, where this apparatus is used, is good or not. CONSTITUTION:A phase control signal generation circuit 8 first gives a phase control signal to a TRIAC 4 corresponding to a motor 3 for conduction and thereafter gives the phase control signal to a TRIAC 6 corresponding to a heater for conduction. At that time, a momentary drop of supply voltage occurs by a rush current flowing through the heater 5, but the second phase control signal is given to the TRIAC 4 so that the TRIAC 4 maintains a conducted state to continue to apply power to the motor 3. Therefore, the number of revolutions of the motor 3 does not decrease from a set value and an air quantity as set can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phase control device.

[0002]

2. Description of the Related Art Conventionally, there is a hair dryer as a phase control device for individually controlling the phases of two loads that are operated in parallel. This hair dryer uses a triac as a phase control element, and connects a heater and a fan rotation motor to an AC power source via a corresponding triac provided to phase-control the energization of the motor to control the rotation speed of the motor. The amount of heat generation is changed by varying the air flow rate and controlling the phase of energization of the heater.

FIG. 6 is a waveform diagram showing the phase control operation of the hair dryer. The phase of the voltage waveform of the AC power supply shown in FIG. 6 (a) corresponds to the heater as shown in FIG. 6 (b). When a phase control signal is applied to the triac, the triac is conducted at that phase and a current flows through the heater. FIG. 7C shows the voltage waveform across the triac.

On the other hand, FIG. 1D shows a phase control signal given to the triac corresponding to the motor, and the triac to which the phase control signal is given becomes conductive as shown in FIG. .

[0005]

By the way, in the above hair dryer, when the power cord is very long, the voltage drop due to the inrush current flowing through the heater is very large when the phase control signal is applied to the triac for the heater to make it conductive. Therefore, the power supply voltage instantaneously drops as shown by (a) in FIG. As a result, the triac corresponding to the motor, which is in the conductive state, is turned off as shown in FIG. 6 (e) to stop energizing the motor. Therefore, there is a problem that the number of rotations of the motor decreases and the air volume decreases, which is less than the set air volume.

That is, in the case where the two loads to be operated in parallel are individually phase-controlled, there is a problem that the phase control for one load is affected when the phase control is performed for one load depending on the environment in which it is used. The present invention has been made in view of the above problems, and an object of the present invention is to provide a phase control device that controls the phases of two loads to be operated in parallel independently of each other, regardless of whether the usage environment is good or bad. It is an object of the present invention to provide a phase control device in which the phase control of one load does not affect the phase control of the other load.

[0007]

In order to achieve the above-mentioned object, the invention of claim 1 is characterized in that two loads to be operated in parallel are separately connected to an AC power source through a phase control element, respectively. After applying the phase control signal to the phase control element of 1,
In a phase control device that applies a phase control signal to the second phase control element during the half cycle period of the same power supply voltage to control the phase of the energization of each load separately, the phase control device approaches the phase control start point of the second phase control element Then, the half cycle of the power supply voltage including the conduction phase ends from the time when the previous phase control signal is applied to the first phase control element so that the next phase control signal is applied to the first phase control element. Up to now, the first phase control element is provided with the phase control signal generating means for applying the phase control signal a plurality of times.

According to a second aspect of the present invention, the two loads to be operated in parallel are separately connected to the AC power source through the phase control element, respectively, and the same phase control signal is applied to the first phase control element. In a phase control device that applies a phase control signal to a second phase control element during a half cycle of a power supply voltage to individually control the energization of each load, the phase control is performed after the phase control of the first phase control element is started. It is provided with a phase control signal generating means for re-applying the phase control signal to the first phase control element when the signal is applied to the second phase control element.

According to a first aspect of the present invention, two loads that are operated in parallel are separately connected to an AC power source via a phase control element, respectively, and the same phase control signal is applied to the first phase control element. In a phase control device that applies a phase control signal to the second phase control element during the half cycle period of the power supply voltage to control the phase of energization of each load separately, until the phase control signal is completely applied to the second phase control element , A phase control signal generating means for continuing to apply the phase control signal to the first phase control element.

[0010]

According to the present invention, even if the second phase control element is turned on after the first phase control element and an inrush current flows to the corresponding load to cause a momentary drop in the power supply voltage, the current is turned on first. The first phase control element that is operating can be kept in a conducting state by being given a phase control signal, so that the load whose conduction is phase-controlled by the first phase control element is connected to the second phase control element. There is no influence of the phase control operation, and normal operation of a predetermined load can be obtained.

[0011]

(Embodiment 1) FIG. 1 shows a circuit configuration of this embodiment used in the hair dryer D shown in FIG. 2. In this embodiment, a fan 2 is connected to an AC power source connected via a plug 1.
A phase control circuit 7 is provided for connecting the motor 3 for rotating the motor via the triac 4 and the heater 5 for connecting to the AC power source via another triac 6. The phase control circuit 7 is provided with a phase control signal generation circuit 8 including a microcomputer for applying a phase control signal to each of the triacs 4 and 6, and a power supply circuit 9 for supplying power to the phase control signal generation circuit 8. There is.

The phase control signal generation circuit 8 determines the conduction phase angle of each triac 4, 6 based on the setting contents of the air volume setting means (not shown) and the air temperature setting means (not shown). In view of the above-mentioned conventional problems, the phase control signal is generated a plurality of times during the half cycle period of the AC power supply voltage.

That is, when the phase control signal generating circuit 8 outputs the phase control signal of the triac 4 corresponding to the motor 3 at an appropriate phase of the AC power source shown in FIG. 3A, as shown in FIG. Is conducted and the motor 3 is energized,
The voltage across the triac 4 is as shown in FIG. Next, as shown in FIG. 3B, the phase control signal of the triac 6 corresponding to the heater 5 is supplied to the phase control signal generation circuit 8
Output, the traac 6 becomes conductive and the heater 5 is energized, and the voltage across the triac 6 becomes as shown in FIG. At this time, an inrush current flows through the heater 5, causing a voltage drop due to the impedance of the power supply cord, and the AC power supply voltage drops for a moment as shown in (a) of the same figure. Since the phase control signal generation circuit 8 outputs the phase control signal for the triac 4 in the vicinity of the time when the phase control signal for the triac 6 is generated, the triac 6 maintains the conductive state and continues to energize the motor 3. Therefore, the rotation speed of the motor 3 does not decrease below the set value, and the air volume can be obtained according to the set value.

(Second Embodiment) In the first embodiment, the phase control signal generation circuit 8 outputs the phase control signal a plurality of times during the half cycle of the AC power supply voltage. When a phase control signal is given to a triac that has been turned on and then turned on, the phase control signal is turned on again and given to the triac when a phase control signal is given to another triac later. is there.

That is, in this embodiment, the phase control signal generation circuit 8 outputs the phase control signal of the triac 4 corresponding to the motor 3 at the appropriate phase of the AC power supply shown in FIG. 4A as shown in FIG. When it is output to, the traac 4 becomes conductive and the motor 3 is energized, and the voltage across the triac 4 becomes as shown in FIG. Next, when the phase control signal generation circuit 8 outputs the phase control signal of the triac 6 corresponding to the heater 5 as shown in FIG. 7B, the traac 6 is turned on and the heater 5 is energized to generate the voltage across the triac 6. Is as shown in FIG. At this time, an inrush current flows through the heater 5, causing a voltage drop due to the impedance of the power supply cord, and the AC power supply voltage drops for a moment as shown by (a) in the same figure. Due to this drop, the triac 6 is about to turn off. In the present embodiment, the phase control signal generation circuit 8 outputs the phase control signal again to the triac 6 to which the phase control signal has been previously given, close to the time when the phase control signal for the triac 4 is generated. Therefore, the triac 6 maintains the conductive state and continues to energize the motor 3. Therefore, the number of rotations of the motor 3 does not decrease below the set value, and the air volume is obtained according to the set value.

Since the circuit configuration is similar to that of the first embodiment, the description of the configuration is omitted. (Third Embodiment) The circuit configuration of this embodiment is similar to that of the first embodiment, but the phase control signal output from the phase control signal generation circuit 8 is different from that of the first and second embodiments. That is, in this embodiment, FIG.
When the phase control signal generation circuit 8 outputs the phase control signal of the triac 4 corresponding to the motor 3 at an appropriate phase of the AC power source shown in FIG. 3A as shown in FIG.
Is conducted to energize the motor 3, and the voltage across the triac 4 becomes as shown in FIG. Next, when the phase control signal generation circuit 8 outputs the phase control signal of the triac 6 corresponding to the heater 5 as shown in (b) of the figure, the traac 6 becomes conductive and the heater 5 is energized to generate the voltage across the triac 6. Is as shown in FIG. At this time, an inrush current flows through the heater 5, causing a voltage drop due to the impedance of the power supply cord, and the AC power supply voltage is momentarily lowered as shown in (a) of FIG.
Turn off, but the phase control signal generation circuit 8
Continuously outputs the phase control signal previously given to the triac 6 until the output of the phase control signal to the triac 4 disappears, the triac 6 maintains the conducting state and continues to energize the motor 3. Therefore, the number of rotations of the motor 3 does not decrease below the set value, and the air volume is obtained according to the set value.

When the device of the present invention is used in the hair dryer as in each of the embodiments, it is possible to obtain the air temperature and the air volume as the set values even in the environment where the power cord is long and the impedance is high.

[0018]

Since the present invention is configured as described above, the second phase control element is rendered conductive after the first phase control element, and a rush current flows through the corresponding load so that the power supply voltage is reduced. Even if an instantaneous drop occurs, the phase control signal is given to the first phase control element that is conducting first, so the conduction state of the first phase control element can be maintained, and therefore the first phase control element can be maintained. The load whose energization is phase-controlled by the control element is not affected by the phase control of the second phase control element, and as a result there is an effect that a normal predetermined load operation can be obtained regardless of the quality of the usage environment. .

[Brief description of drawings]

FIG. 1 is a circuit diagram of a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of the hair dryer of the above.

FIG. 3 is a waveform diagram for explaining the operation of the above.

FIG. 4 is a waveform diagram for explaining the operation of the second embodiment of the present invention.

FIG. 5 is a waveform diagram for explaining the operation of the third embodiment of the present invention.

FIG. 6 is a waveform diagram for explaining the operation of a conventional example.

[Explanation of symbols]

 3 Motor 4 Triac 5 Heater 6 Triac 7 Phase control circuit 8 Phase control signal generation circuit

Claims (3)

[Claims] 1. A half cycle of the same power supply voltage after connecting two loads to be operated in parallel to an AC power supply through a phase control element and applying a phase control signal to the first phase control element, respectively. In a phase control device that applies a phase control signal to a second phase control element during a period to individually control the energization of each load, the first phase control device approaches the phase control start time of the second phase control element. The first phase is controlled from the time when the previous phase control signal is applied to the first phase control element to the end of the half cycle of the power supply voltage including the conduction phase so that the next phase control signal is applied to the control element. A phase control device comprising phase control signal generation means for applying a phase control signal to a control element a plurality of times. 2. Two half-cycles of the same power supply voltage are respectively connected to an AC power supply through a phase control element, and two loads to be operated in parallel are respectively connected to an AC power supply and a phase control signal is applied to the first phase control element. In a phase control device that applies a phase control signal to the second phase control element during a period to individually control the energization of each load, the phase control signal is supplied to the second phase control element after the phase control of the first phase control element is started. When applying to the phase control element, the first
And a phase control signal generating means for applying a phase control signal to the phase control element again. 3. A half cycle of the same power supply voltage after connecting two loads to be operated in parallel to an AC power supply via a phase control element and applying a phase control signal to the first phase control element, respectively. In a phase control device that applies a phase control signal to a second phase control element during a period of time to individually control the energization of each load, until the first phase control signal is applied to the second phase control element, A phase control device comprising phase control signal generation means for continuing to apply a phase control signal to a control element.