Circuit applicable to double voltages and double-voltage blower

Abstract

The utility model discloses a circuit suitable for double voltages, comprising a power supply circuit, the input end of which is electrically connected with a commercial power, and the AC commercial power is subjected to filtering rectification and then boost or buck into DC voltages with different values for output; the input end of the zero-cross detection circuit is electrically connected with the input end of the power supply circuit, and the zero-cross detection circuit detects the zero-cross position of the mains supply and outputs a signal to the MCU control circuit; the MCU control circuit comprises an MCU chip, and the MCU chip outputs a control signal after receiving the input signal and running the input signal; the heating control circuit is electrically connected with the MCU chip and the heating tube respectively, and the heating control circuit receives signals of the MCU chip to control the heating tube to heat; and the motor driving circuit drives the motor to operate. The applicable voltage of the circuit is 110 / 220V, and the dual-voltage blower adopting the circuit can be normally used under two kinds of commercial power voltages of 110 / 220V without additional steps.

Description

Technical Field

[0001] The utility model relates to the technical field of hair dryer power supply, in particular to a dual-voltage circuit and a dual-voltage hair dryer. Background Art

[0002] At present, there are two international standard electricity voltages: 110V and 220V. For example, the United States, Canada and other countries use 110V, while China, France, Germany and other countries use 220V.

[0003] Hair dryers that use a single voltage standard may create safety hazards if they are turned on with the wrong voltage. For example, a hair dryer with a standard voltage of 110VAC will be burned if used on a 220VAC voltage; a hair dryer with a standard voltage of 220VAC will not work properly if used on a 110V voltage.

[0004] In this way, when producing hair dryers, two production lines need to be set up, one to produce hair dryers rated at 110VAC, and the other to produce hair dryers rated at 220VAC, which increases the production cost of the company's hair dryers. Utility Model Content

[0005] The utility model aims to provide a dual-voltage circuit and a dual-voltage hair dryer. The applicable voltage of the circuit is 110V / 220V. The dual-voltage hair dryer adopting the circuit can be used normally under two types of mains voltages.

[0006] The above technical objectives of the present invention are achieved through the following technical solutions: A dual voltage circuit comprising:

[0007] A power supply circuit, wherein the input end of the power supply circuit is electrically connected to the mains power, and the AC mains power is filtered and rectified and then stepped up or stepped down to output a DC voltage of different values;

[0008] A zero-crossing detection circuit, wherein an input end of the zero-crossing detection circuit is electrically connected to an input end of the power supply circuit, and the zero-crossing detection circuit detects the zero-crossing position of the mains power and outputs a signal to the MCU control circuit;

[0009] MCU control circuit, the MCU control circuit includes an MCU chip, the MCU chip receives an input signal and outputs a control signal after operation;

[0010] A heating control circuit, the heating control circuit being electrically connected to the MCU chip and the heating tube, and the heating control circuit receiving a signal from the MCU chip to control the heating of the heating tube;

[0011] A driving circuit drives the motor to operate.

[0012] By adopting the above technical solution, the power supply circuit converts AC mains power into DC output, the zero-crossing detection circuit detects the zero-crossing point of the AC power and sends it to the MCU chip. The MCU chip outputs a signal to control the on-off of the heating control circuit at the zero-crossing point, so that the heating tube generates heat at rated power under a voltage of 110 / 220V; the drive circuit inverts the DC voltage and outputs a drive motor to rotate.

[0013] The present invention is further configured as follows: the power supply circuit includes capacitors C37, C34, C35, resistors R5, R8, a varistor RV1, and a bridge rectifier DB1; the capacitors C37, C34, C35 and the varistor RV1 are configured in parallel.

[0014] The present invention is further configured as follows: the power supply circuit further includes a voltage stabilizing chip U1 and its auxiliary circuits and a voltage stabilizing chip U2 and its auxiliary circuits; the voltage stabilizing chip U1 outputs a 12V DC voltage; and the voltage stabilizing chip U2 outputs a 5V DC voltage.

[0015] The present utility model is further configured as follows: the zero-crossing detection circuit includes a photocoupler U3 and a transistor Q1, pins 1 and 2 of the light-emitting end of the photocoupler U3 are electrically connected to the power supply circuit, pin 3 of the photosensitive end of the photocoupler U3 is electrically connected to the ground point, and pin 4 is electrically connected to a 5V voltage and the base B of the transistor Q1.

[0016] By adopting the above technical solution, the zero-crossing detection circuit outputs a pulse voltage signal.

[0017] The present invention is further configured as follows: the heating control circuit includes an optical coupler U5 and an optical coupler U6, and the optical coupler U5 and the optical coupler U6 are respectively connected to the MCU chip by signals.

[0018] The present invention is further configured as follows: the optocoupler U5 and the optocoupler U6 are both zero-crossing bidirectional thyristor optocouplers.

[0019] By adopting the above technical solution, the zero-crossing bidirectional thyristor optocoupler is triggered to turn on when the AC voltage crosses the zero point, which can reduce electromagnetic interference and switching loss and extend the service life of the circuit.

[0020] The present invention is further configured as follows: the drive circuit includes a drive chip and a three-phase inverter circuit, the drive chip signal is connected to the MCU chip, and the drive chip output signal switches the three-phase inverter circuit.

[0021] By adopting the above technical solution, the driver chip and the MCU chip transmit data, and the driver chip switches the three-phase inverter circuit on and off, so that the three-phase inverter circuit outputs current to drive the motor to rotate.

[0022] The present invention is further configured as follows: the three-phase inverter circuit includes a field-effect transistor Q2, a field-effect transistor Q5, and a field-effect transistor Q6, which together constitute a six-arm full-bridge drive, wherein the field-effect transistor Q2, the field-effect transistor Q5, and the field-effect transistor Q6 are respectively provided with an upper bridge arm and a lower bridge arm, wherein the upper bridge arm and the lower bridge arm are respectively connected to the drive chip for signal connection, and the field-effect transistor Q2, the field-effect transistor Q5, and the field-effect transistor Q6 are respectively connected to the U, V, and W phases of the motor.

[0023] By adopting the above technical solution, the driver chip outputs a PWM signal to adjust the speed of the motor.

[0024] A dual-pressure hair dryer includes a handle and a hair dryer housing. A control panel is provided in the handle. A circuit is provided on the control panel. The circuit includes the above-mentioned dual-voltage circuit.

[0025] The utility model is further configured as follows: a heating tube, a negative ion generator and a motor are arranged in the blowing shell.

[0026] Compared with the prior art, the present invention has the following beneficial effects: the applicable voltage of the circuit of the present invention is 110 / 220V, and the dual-pressure hair dryer using this circuit can be used normally under two types of mains voltages of 110 / 220V without the need for additional steps. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 1 is a circuit structure principle diagram of a dual-pressure hair dryer in an embodiment.

[0028] Figure 2 It is a principle block diagram of a circuit applicable to dual voltage in an embodiment.

[0029] Figure 3 1 is a power supply circuit diagram of a dual voltage circuit in an embodiment.

[0030] Figure 4 1 is a zero-crossing detection circuit diagram in a dual-voltage circuit according to an embodiment.

[0031] Figure 5 This is a circuit diagram of an MCU control circuit in a dual voltage circuit according to an embodiment.

[0032] Figure 6 This is a heating control circuit diagram for a dual voltage circuit in an embodiment.

[0033] Figure 7 2 is a diagram of a driver chip in a dual voltage circuit according to an embodiment of the present invention.

[0034] Figure 8This is a three-phase inverter circuit diagram in a dual-voltage circuit according to an embodiment.

[0035] Figure 9 2 is a perspective view of a dual-pressure hair dryer according to an embodiment.

[0036] Figure 10 2 is a cross-sectional view of a dual-pressure hair dryer in an embodiment.

[0037] In the figure: 1. Power supply circuit; 2. Zero-crossing detection circuit; 3. MCU control circuit; 4. Heating control circuit; 5. Drive circuit; 10. Handle; 11. Hair dryer housing; 12. Control board; 13. Heating tube; 14. Motor. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0039] like Figure 1-2 As shown, this embodiment discloses a circuit suitable for dual voltage, which includes a power supply circuit 1, a zero-crossing detection circuit 2, an MCU control circuit 3 and a drive circuit 5. The input end of the power supply circuit 1 is electrically connected to the AC mains, and the power supply circuit 1 filters and rectifies the AC mains and then boosts or steps down the voltage to a DC voltage of different values ​​for output; the input end of the zero-crossing detection circuit 2 is electrically connected to the input end of the power supply circuit 1, and the zero-crossing detection circuit 2 detects the zero-crossing position of the AC mains and outputs a signal to the MCU control circuit 3; the MCU control circuit 3 includes an MCU chip, and the MCU chip receives the input signal and outputs a control signal after running; the drive circuit 5 includes a drive chip and a three-phase inverter circuit, and the drive chip signal is connected to the MCU chip for data transmission. The three-phase inverter circuit is electrically connected to the drive chip, and the three-phase inverter circuit receives the signal output by the drive chip to drive the motor 14 to run.

[0040] like Figure 3As shown, the power supply circuit 1 is connected in parallel with capacitors C37, C34, and C35 for filtering, a fuse F1 is connected in series, and a varistor RV1 is connected in parallel to provide overvoltage protection and suppress surge voltage; the power supply circuit 1 is provided with a bridge rectifier DB1, which rectifies the AC mains and outputs the output voltage DCP to the drive circuit 5; the power supply circuit 1 is provided with a voltage regulator chip U1, which steps down and stabilizes the DC voltage and then outputs a 12V DC voltage; the power supply circuit 1 is also provided with a voltage regulator chip U2, which is electrically connected to the voltage regulator chip U1, and the voltage regulator chip U2 and its auxiliary circuits further step down and stabilize the 12V DC voltage into a 5V DC voltage.

[0041] like Figure 4 As shown, the zero-crossing detection circuit 2 includes a photocoupler U3 and a transistor Q1. The input pins 1 and 2 of the photocoupler U3 are electrically connected to the power supply circuit 1, the output pin 3 is electrically connected to the ground point, and the pin 4 is electrically connected to the 5V voltage and the base B of the transistor Q1; the pin 1 of the photocoupler U3 is electrically connected to the voltage divider resistors R15 and R16, the parallel voltage regulator diode D6 and the capacitor C18, the voltage divider resistors R15 and R16 share the voltage drop of the power supply, and the parallel voltage regulator diode D6 limits the voltage value of the input photocoupler U3 to prevent the photocoupler U3 from being burned out due to overcurrent; when the input AC sine wave voltage is positive, the photocoupler When the input AC power is a sine wave with a negative voltage, the optocoupler U3 is turned on, the base B of the transistor Q1 is triggered, the transistor Q1 is turned on, and the output terminal T6 has a voltage output as a high level electricity. When the input AC power is a sine wave with a negative voltage, the optocoupler U3 is turned off, the base B of the transistor Q1 is not triggered by current, the transistor Q1 is turned off, and the output terminal T6 has no voltage output as a low level electricity. The zero-crossing detection circuit 2 outputs a pulse signal periodically according to the frequency of the AC mains, and the MCU chip receives it to determine the zero-crossing point of the AC sine wave. The MCU chip outputs a signal according to the zero-crossing point, and the output signal repeatedly turns on and off the heating control circuit 4, so that the heating tube 13 heats up at the rated power.

[0042] like Figure 5 As shown, the MCU control circuit 3 includes an MCU chip, which is chip U6. The chip U6 is connected to various functional circuits by signal, receives input signals, and outputs control signals to ensure the operation of each circuit.

[0043] like Figure 6 As shown, the heating control circuit 4 is electrically connected to the heating element and the MCU chip. The heating control circuit 4 receives the signal output by the MCU chip and controls the heating element to generate heat. The heating control circuit 4 includes a photocoupler U5 and a photocoupler U7. The photocoupler U5 and the photocoupler U7 respectively receive the signal from the MCU chip and turn on to start the heating element, so that the heating element generates heat.

[0044] In the embodiment of the present invention, the optocoupler U5 and the optocoupler U6 are both zero-crossing bidirectional thyristor optocouplers.

[0045] like Figure 7 As shown, the driving chip is chip U4, and the chip U4 model is FU6862L. The driving chip signal is connected to the MCU chip for data transmission. The driving chip sends a signal to make the driving chip output a signal to open and close the switching device in the three-phase inverter circuit, so that the motor 14 rotates.

[0046] like Figure 8 As shown, the three-phase inverter circuit is a full-bridge inverter circuit. The three-phase inverter circuit is driven by a six-arm full-bridge composed of field effect transistors Q2, Q5, and Q6. The field effect transistors Q2, Q5, and Q6 each include two field effect transistors. The six field effect transistors are divided into two groups of three-phase bridge arms, each bridge arm includes a field effect transistor and a diode. The field effect transistors Q2, Q5, and Q6 are respectively connected to the three phases U, V, and W of the motor 14. Each bridge arm is respectively connected to the positive and negative poles of the power supply, and the middle part of the bridge arm is connected to the motor 14 line; as shown in FIG. As shown, the drain D1 of the field effect transistor Q2 is connected to the positive pole of the power supply DCP, the source S2 is connected to the negative pole grounding point GND of the power supply, and after the source S1 and the drain D2 are connected, they are jointly connected to the U phase output line of the motor 14. The base G1 of the field effect transistor Q2 is connected to the PWM_UH end of the driving chip, and the base G2 of the field effect transistor Q2 is connected to the PWM_UL and PWM_UH of the driving chip. The field effect transistor Q2 receives the PWM signal of the driving chip to adjust the speed of the motor 14; the field effect transistors Q5 and Q6 are connected in the same way.

[0047] like Figure 9 、 Figure 10 As shown, the dual-pressure hair dryer includes a handle 10 and a hair drying shell 11. A control panel 12 is provided in the handle 10, and the control panel 12 is provided with the above-mentioned dual-voltage circuit; at the same time, a heating tube 13, a negative ion generator (not marked in the drawing) and a motor 14 are provided in the hair drying shell 11. The heating tube 13, the negative ion generator and the motor 14 are electrically connected to the control panel 12 respectively. The control panel 12 outputs electrical energy to heat the heating tube 13, and the control panel 12 outputs electrical energy to rotate the motor 14 to drive the blades to blow out air. At the same time, the motor 14 is a high-speed motor, and the wind speed can be adjusted by the gear.

[0048] The above description is only a preferred embodiment of the present invention. Therefore, any equivalent changes or modifications made according to the structure, features and principles described in the scope of the present invention patent application are included in the scope of the present invention patent application.

Claims

1. A dual voltage circuit, characterized in that: include: A power supply circuit (1), wherein the input end of the power supply circuit (1) is electrically connected to AC mains power, and the AC mains power is filtered and rectified and then stepped up or stepped down to output a DC voltage of different values; A zero-crossing detection circuit (2), wherein an input end of the zero-crossing detection circuit (2) is electrically connected to an input end of the power supply circuit (1), and the zero-crossing detection circuit (2) detects the zero-crossing position of the AC mains power and outputs a signal to the MCU control circuit (3); An MCU control circuit (3), wherein the MCU control circuit (3) comprises an MCU chip, wherein the MCU chip receives an input signal and outputs a control signal after operation; A heating control circuit (4), the heating control circuit (4) being electrically connected to the MCU chip and the heating tube (13), and the heating control circuit (4) receiving a signal from the MCU chip to control the heating tube (13) to heat; A drive circuit (5), wherein the drive circuit (5) drives the motor (14) to operate.

2. The dual voltage circuit according to claim 1, characterized in that: The power supply circuit (1) comprises capacitors C37, C34, C35, resistors R5, R8, a varistor RV1, and a bridge rectifier DB1; the capacitors C37, C34, C35 and the varistor RV1 are arranged in parallel.

3. The dual voltage circuit according to claim 2, characterized in that: The power supply circuit (1) further comprises a voltage stabilizing chip U1 and its auxiliary circuits and a voltage stabilizing chip U2 and its auxiliary circuits. The voltage stabilizing chip U1 outputs a 12V DC voltage, and the voltage stabilizing chip U2 outputs a 5V DC voltage.

4. The dual voltage circuit according to claim 1, characterized in that: The zero-crossing detection circuit (2) comprises a photocoupler U3 and a transistor Q1, wherein pins 1 and 2 of the light-emitting end of the photocoupler U3 are electrically connected to the power supply circuit (1), pin 3 of the light-sensitive end of the photocoupler U3 is electrically connected to a ground point, and pin 4 is electrically connected to a 5V voltage and a base B of the transistor Q1.

5. The dual voltage circuit according to claim 1, characterized in that: The heating control circuit (4) comprises an optical coupler U5 and an optical coupler U6, and the optical coupler U5 and the optical coupler U6 are respectively connected to the MCU chip by signals.

6. The dual voltage circuit according to claim 5, characterized in that: The optocoupler U5 and the optocoupler U6 are both zero-crossing bidirectional thyristor optocouplers.

7. The dual voltage circuit according to claim 1, characterized in that: The driving circuit (5) comprises a driving chip and a three-phase inverter circuit, wherein the driving chip signal is connected to the MCU chip, and the driving chip outputs a signal to open and close the three-phase inverter circuit.

8. The dual voltage circuit according to claim 7, characterized in that: The three-phase inverter circuit includes a field effect transistor Q2, a field effect transistor Q5, and a field effect transistor Q6. The field effect transistor Q2, the field effect transistor Q5, and the field effect transistor Q6 together form a six-arm full-bridge drive. The field effect transistor Q2, the field effect transistor Q5, and the field effect transistor Q6 are respectively provided with an upper bridge arm and a lower bridge arm. The upper bridge arm and the lower bridge arm are respectively connected to the drive chip for signal connection. The field effect transistor Q2, the field effect transistor Q5, and the field effect transistor Q6 are respectively connected to the U, V, and W phases of the motor (14).

9. Double pressure hair dryer, characterized by: The dual-pressure hair dryer comprises a handle (10) and a blowing shell (11), wherein a control panel (12) is provided in the handle (10), and a circuit is provided on the control panel (12), wherein the circuit comprises a dual-voltage circuit as described in any one of claims 1 to 8.

10. The dual-pressure hair dryer according to claim 9, characterized in that: A heating tube (13), a negative ion generator and a motor (14) are provided in the blowing housing (11).

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