JP2018174608A - Brushless dc motor with built-in circuit and ceiling fan mounting the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brushless DC motor with a built-in circuit, which can easily switch a rotation direction of a blade without increasing the number of lead wires.SOLUTION: A control circuit 4 comprises: amplitude voltage detection means for comparing amplitude voltage of a speed command signal with first threshold voltage and second threshold voltage, which are previously determined, and detecting the amplitude voltage; and rotation direction determining means 12 for determining a rotation direction to be a normal rotation when a result of the amplitude voltage, which is determined by the amplitude voltage detection means 11, is equal to or more than a first threshold and below a second threshold, and determining the rotation direction to be a reverse direction when the result is equal to or more than the first threshold and equal to or more than the second threshold. Thus, a brushless DC motor 1 with a built-in circuit, which is capable of simultaneously transmitting a rotational direction command and a rotational frequency command of a rotor 107 without increasing the number of lead wires, and a ceiling fan mounting the motor can be provided.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a high-efficiency brushless DC motor used for, for example, a ceiling fan, and more specifically, a brushless DC motor with a built-in circuit having a mold outer covering a stator and a control circuit including an inverter circuit that drives the motor, The present invention relates to a method for controlling a brushless DC motor in a ceiling fan or the like on which this is mounted.

  Conventionally, this type of ceiling fan has a structure as shown in FIG.

  As shown in FIG. 10, the ceiling fan 101 is provided with an illuminator 102 at the bottom. The ceiling fan 101 includes a built-in brushless DC motor 103 and an external control circuit 104. The blade 105 is attached to a circuit-less brushless DC motor 103 and is rotated.

  The control circuit receives a speed command signal for controlling the rotational speed of the DC motor 103 from the external control circuit 104. The driving of the DC motor 103 is controlled based on the speed command signal (see, for example, Patent Document 1).

  FIG. 11 is a cross-sectional view of a conventional brushless DC motor with a built-in circuit.

  As shown in FIG. 11, the motor 106 includes a rotor 107 and a stator 108.

  The rotor 107 is formed by mixing ferrite magnet powder and resin, and a shaft 109 is press-fitted into a permanent magnet whose surface is alternately provided with N poles and S poles. A ball bearing 110 is press-fitted into the shaft 109, and the ball bearing 110 is fixed by a bracket 111.

  The shaft 109 is made of metal such as stainless steel and has a structure in which a blade is attached to the tip.

  The bracket 111 is made of metal and is in close contact with the stator 108 to support the blade load.

  The stator 108 has a three-phase winding 112 wound around an iron core in which electromagnetic steel plates are laminated.

  The brushless DC motor 103 with a built-in circuit is covered and integrated with a resin that also serves as an insulation between the motor 106 and the printed circuit board 113, for example, a thermosetting resin 114 mainly composed of unsaturated polyester.

  The bushing 115 is made of resin, and the power line 116 and the signal lead wire 117 are connected to the printed board 113 of the circuit-less brushless DC motor 103 through the bushing 115.

  The power line 116 is supplied with motive power for driving the motor 106.

  The signal lead wire 117 communicates the speed command signal and the frequency generation signal.

  The speed command signal is a speed command for controlling the air volume generated by the rotation of the blades attached to the motor 106 and obtaining a target air volume. The frequency generation signal indicates the number of rotations at which the blades are rotating. The signal is transmitted.

  The capacitor 118, the inverter circuit 119, and the control circuit 120 are mounted on the printed board 113.

  As a speed signal input to the control circuit 120, a PWM (Pulse Width Modulation) signal is used.

  FIG. 12 is a block diagram of a brushless DC motor with a built-in circuit when the speed command signal is a PWM signal.

  Hereinafter, a basic configuration of a conventional control circuit will be described with reference to FIG.

  A speed command signal is output from the external control circuit 121. The control circuit 120 determines the on / off period of the PWM signal from the input speed command signal, calculates the on / off ratio, that is, the duty, and outputs the drive control signal of the motor 106 to the inverter circuit 119. It is like that.

  A voltage is applied from the inverter circuit 119 to the winding 112 of the motor 106 to pass a current through the winding 112, and the motor 106 is rotated in a predetermined rotation direction.

  13 shows a PWM signal output as a speed command signal from the external control circuit 121. FIG. 13 (a) shows a speed command signal when the duty is large, and FIG. 13 (b) shows a speed command when the duty is small. Signals are shown.

  FIG. 13A shows a PWM signal output as a speed command signal from the external control circuit 121. The pulse signal period is made constant and the pulse width is varied to obtain a speed command signal. The pulse period T is 1 ms, and is turned on when the amplitude voltage is 5V, and turned off when the amplitude voltage is 0V. When the ON period is Ton and the OFF period is Toff, the ratio of ON to OFF, that is, the duty DUTY is obtained by Equation 1.

DUTY = Ton / (Ton + Toff) = Ton / T (Formula 1)
FIG. 13A shows a speed command signal in which the ON period Ton and the OFF period Toff are equal. In this case, the duty DUTY is 0.5.

  In FIG. 13B, the on period Ton and the off period Toff are Ton <Toff, and the duty DUTY in this case is smaller than 0.5. As described above, when the duty ratio is increased by changing the ON / OFF ratio, that is, the duty DUTY, the motor current flowing in the winding 112 of the motor 106 increases, and therefore the motor 106 rotates faster. Conversely, if the duty DUTY is reduced, the motor current flowing through the winding 112 of the motor 106 is reduced, so that the rotation of the motor 106 is delayed.

  Thus, the conventional control circuit 120 has a configuration that can change only the rotational speed of the motor 106 based on the speed command signal.

  The control circuit 120 outputs a frequency generation signal using a rotation speed pulse based on the rotation speed of the motor 106 to the external control circuit 121.

  The external control circuit 121 detects the current rotation state of the motor 106 based on the rotation number pulse, and outputs a speed command signal to the control circuit 120 so as to obtain a predetermined rotation speed, thereby speed feedback control. It is carried out.

  This rotation speed pulse is proportional to the rotation speed.

  FIG. 14 shows a frequency generation signal using a rotation speed pulse.

  14A shows a frequency generation signal when rotating in the forward rotation direction, and FIG. 14B shows a frequency generation signal when rotating in the reverse rotation direction. In either case, a state of rotating at the same rotational speed is shown.

  As the frequency generation signal, a rotation speed pulse signal is output based on the rotation speed of the motor 106. For example, when the motor 106 makes one rotation, a signal with an amplitude voltage of 5 V is output. When the rotation speed increases, the number of pulses per rotation increases, and when the rotation speed decreases, the number of pulses per rotation decreases.

  FIG. 14A and FIG. 14B are different in the rotating direction, but have the same number of rotations, so that one rotation pulse is four pulses.

  For this reason, it is difficult to determine from the conventional frequency generation signal whether the rotation is in the forward rotation direction or the reverse rotation direction.

JP 2005-39943 A

  However, in a brushless DC motor with a built-in circuit in which a circuit board having such a conventional inverter circuit is integrally molded with resin, a cool breeze is generated in the summer and a warm air gathered near the ceiling is circulated in the winter. In summer and winter, it is required that the rotation direction of the blades can be easily switched. For this purpose, a rotation direction command line is provided between the external control circuit and the control circuit to switch the rotation direction. It is necessary to transmit the rotation direction command signal. That is, a rotation direction command line for transmitting a rotation direction command signal is required in addition to the power line 116 and the signal lead wire 117.

  On the other hand, it is necessary to improve the sealing of the bushing of the lead wire lead-out part to protect against intrusion of condensation and rainwater, etc., and to improve the sealing of the bushing of the lead wire lead-out part to prevent resin leakage during molding It has a problem that it must be present, and it is difficult to simply increase the number of lead wires or to bundle them.

  Even if the number of lead wires can be increased, it is difficult to prevent water leakage and resin leakage during molding to prevent condensation and rainwater from entering, and space for storing lead wires is required. Therefore, the configuration of a ceiling fan using a molded brushless DC motor with a built-in circuit is difficult, such as bushing becoming larger and mounting of the bushing becomes difficult.

SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object thereof is to provide a brushless DC motor with a built-in circuit that can easily switch the rotation direction of the blades without increasing the number of lead wires.

  In order to achieve this object, a brushless DC motor with a built-in circuit according to the present invention uses a rotor provided with a permanent magnet, a stator provided with a three-phase winding, and a DC voltage input from a DC power supply. The three switching elements are pulled in through a capacitor to a plurality of upper switching elements connected to the positive side and a plurality of lower switching elements connected to the negative side to perform switching between the upper switching element and the lower switching element. An inverter circuit for applying a driving voltage to the phase winding, a control circuit for controlling the operation of the inverter circuit, a mold shell for covering the stator, the inverter circuit, and the control circuit, a power line, and the rotational speed of the rotor A speed command line for controlling the frequency, and the control circuit generates a frequency generation signal with an amplitude voltage determined in advance based on the rotational speed of the rotor. And a frequency generation signal means for comparing the amplitude voltage of the speed command signal with a predetermined first threshold voltage and a second threshold voltage to determine the amplitude voltage. And when the result of the amplitude voltage detected by the amplitude voltage detection means is greater than or equal to the first threshold value and less than the second threshold value, the rotation direction is determined to be normal rotation, and the first threshold value is determined. When the value is equal to or greater than the second threshold value, the rotation direction is determined to be the reverse rotation direction, and the rotation direction command and the rotation number command of the rotor are obtained by switching the amplitude voltage of the speed command signal. It is intended to convey at the same time, thereby achieving the intended purpose.

  Further, in the present invention, the frequency generating means generates a frequency generation signal with a first amplitude voltage when the rotor is rotating in the forward rotation, and the rotor is rotating in the reverse rotation. The frequency generation signal is generated with the second amplitude voltage, and the rotation direction and the number of rotations of the rotor are simultaneously transmitted by switching the amplitude voltage of the frequency generation signal. Is achieved.

  According to the present invention, the frequency generation means generates a frequency generation signal with a first amplitude voltage when the rotor is stopped, and simultaneously transmits the rotation direction and the rotation speed of the rotor. In this way, the intended purpose is achieved.

  Further, the present invention is a ceiling fan equipped with a brushless DC motor with a built-in circuit, thereby achieving the intended purpose.

  According to the present invention, the amplitude voltage detecting means for comparing the amplitude voltage of the speed command signal with a predetermined first threshold voltage and a second threshold voltage to determine the amplitude voltage, and When the result of the amplitude voltage detected by the amplitude voltage detection means is not less than the first threshold value and less than the second threshold value, the rotation direction is determined to be normal rotation, and is not less than the first threshold value and If it is equal to or greater than the second threshold value, the rotation direction determination means for rotating the rotation direction in the reverse direction is used, and the rotation direction command of the rotor is increased without increasing the number of leads by switching the amplitude voltage of the speed command signal. And the rotation speed command can be transmitted simultaneously.

  According to the present invention, when the rotor is rotating in the forward rotation, a frequency generation signal is generated with the first amplitude voltage, and when the rotor is rotating in the reverse rotation, the second amplitude voltage is generated. By generating the frequency generation signal and switching the amplitude voltage of the frequency generation signal, it is possible to obtain the effect that the rotation direction and the rotation speed of the rotor can be transmitted simultaneously without increasing the number of lead wires.

According to the present invention, when the rotor is stopped, the frequency generation signal is generated with the first amplitude voltage, so that the rotation direction and the rotation speed of the rotor can be simultaneously adjusted without increasing the number of lead wires. The effect of being able to communicate can be obtained.

  According to the present invention, a brushless DC motor with a built-in circuit having a small size and good controllability can be easily switched without increasing the number of lead wires by using a ceiling fan equipped with a brushless DC motor with a built-in circuit. The effect that a ceiling fan equipped with can be obtained can be obtained.

Cross-sectional view of a brushless DC motor with a built-in circuit according to the present invention and a brushless DC motor with a built-in circuit of a ceiling fan equipped with the same Block diagram The figure which shows the speed command signal ((a) The figure which shows the speed command signal of forward rotation (b) The figure which shows the speed signal of reverse rotation) A diagram showing a state of outputting a forward rotation speed command signal detected by the same amplitude voltage detection means The figure showing how to output the reverse rotation speed command signal detected by the same amplitude voltage detection means Flow chart for determining the rotation direction The figure which shows the same frequency generation signal ((a) The figure which shows the frequency generation signal at the time of forward rotation (b) The figure which shows the frequency generation signal at the time of reverse rotation) The figure which shows the frequency generation signal at the time of the stop The figure which shows the ceiling fan which mounts the same circuit built-in brushless DC motor The figure which shows the ceiling fan carrying the brushless DC motor with a built-in circuit of the conventional brushless DC motor with a built-in circuit and a ceiling fan carrying the same Cross section of brushless DC motor with built-in circuit Block diagram The figure which shows the speed command signal ((a) The figure which shows the speed command signal when the duty is large (b) The figure which shows the speed command signal when the duty is small) The figure which shows the same frequency generation signal ((a) The figure which shows the frequency generation signal at the time of forward rotation (b) The figure which shows the frequency generation signal at the time of reverse rotation)

  The brushless DC motor with a built-in circuit according to the present invention includes a rotor provided with a permanent magnet, a stator provided with a three-phase winding, and a DC voltage input from a DC power source connected to the positive side via a capacitor. An inverter circuit that draws in a plurality of upper switching elements and a plurality of lower switching elements connected to the negative side, and applies a driving voltage to the three-phase winding by switching between the upper switching element and the lower switching element A control circuit that controls the operation of the inverter circuit, a mold shell that covers the stator, the inverter circuit, and the control circuit, a power line and a speed command line that controls the rotational speed of the rotor, The control circuit includes a frequency generation signal means for generating a frequency generation signal with a predetermined amplitude voltage based on the rotation speed of the rotor; Amplitude voltage detection means for comparing the amplitude voltage of the speed command signal with a predetermined first threshold voltage and a second threshold voltage to determine the amplitude voltage, and the amplitude voltage detection means When the detected result of the amplitude voltage is not less than the first threshold value and less than the second threshold value, the rotation direction is determined to be normal rotation, and is not less than the first threshold value and the second threshold value. When the value is greater than or equal to the value, the rotation direction determining means is configured to reverse the rotation direction, and the amplitude voltage of the speed command signal is switched. Thereby, there is an effect that the rotation direction command and the rotation number command of the rotor can be transmitted simultaneously without increasing the number of lead wires.

The frequency generation means generates a frequency generation signal with a first amplitude voltage when the rotor is rotating in the forward direction, and a second frequency when the rotor is rotated in the reverse direction. By generating a frequency generation signal with an amplitude voltage and switching the amplitude voltage of the frequency generation signal, the rotation direction and the number of rotations of the rotor are simultaneously transmitted. Thereby, there is an effect that the rotation direction and the rotation number of the rotor can be transmitted simultaneously without increasing the number of lead wires.

  Further, the frequency generation means has a configuration in which when the rotor is stopped, a frequency generation signal is generated with a first amplitude voltage, and the rotation direction and the rotation speed of the rotor are simultaneously transmitted. Thereby, there is an effect that the rotation direction and the rotation number of the rotor can be transmitted simultaneously without increasing the number of lead wires.

  Moreover, it is a ceiling fan equipped with a brushless DC motor with a built-in circuit, and is equipped with a brushless DC motor with a small and good controllability that can easily change the rotation direction of the blades without increasing the number of lead wires. There is an effect that a ceiling fan can be made.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following embodiment is an example embodying the present invention, and does not limit the technical scope of the present invention.

  In addition, throughout the drawings, the same portions are denoted by the same reference numerals, and the second and subsequent descriptions are omitted. Further, in each of the drawings, description of details of each part not directly related to the present invention is omitted.

(Embodiment 1)
First, the configuration of the circuit-less brushless DC motor 1 will be described with reference to FIG. FIG. 1 is a cross-sectional view of the brushless DC motor 1 with a built-in circuit according to the first embodiment.

  As shown in FIG. 1, the motor 106 includes a rotor 107 and a stator 108.

  The rotor 107 is formed by mixing ferrite magnet powder and resin, and a shaft 109 is press-fitted into a permanent magnet whose surface is alternately provided with N poles and S poles. A ball bearing 110 is press-fitted into the shaft 109, and the ball bearing 110 is supported by a bracket 111.

  The shaft 109 is made of metal such as stainless steel and has a structure in which a blade is attached to the tip. The ball bearing 110 includes an outer ring and an inner ring. The ball bearing 110 includes a cage that holds the balls between the outer ring and the inner ring, and is filled with lubricating oil. The ball bearing 110 reduces wear and friction during rotation of the rotor 107.

  The bracket 111 is made of metal and is in close contact with the stator 108 to support the blade load.

  The stator 108 has a three-phase winding 112 wound around an iron core in which electromagnetic steel plates are laminated.

  The brushless DC motor 1 with a built-in circuit is covered and integrated with a resin that also serves as an insulation between the motor 106 and the printed circuit board 2, for example, a thermosetting resin 114 mainly composed of unsaturated polyester, and is molded. .

  The bushing 115 is made of resin, and the power line 116 and the signal lead wire 3 are connected to the printed board 2 of the brushless DC motor 1 with a built-in circuit through the bushing 115.

  The power line 116 is supplied with motive power for driving the motor 106.

  The signal lead wire 3 includes a speed command signal and a frequency generation signal. The speed command signal is a speed command for controlling the air volume generated by the rotation of the blades attached to the motor 106 and obtaining a target air volume. The frequency generation signal indicates the number of rotations at which the blades are rotating. The signal is transmitted.

  A capacitor 118, an inverter circuit 119, and a control circuit 4 are mounted on the printed board 2.

  The capacitor 118, the inverter circuit 119, and the control circuit 4 will be described later.

  Hereinafter, a description will be given with reference to FIG. FIG. 2 is a block diagram of a brushless DC motor with a built-in circuit.

  A DC voltage is supplied from the power line 116 connected to the external control circuit 5 to the inverter circuit 119 via the capacitor 118.

  The inverter circuit 119 has a three-phase bridge configuration, and includes six switching elements Q1, Q2, Q3, Q4, Q5, and Q6 that constitute the three-phase bridge. Switching elements Q1, Q2, and Q3 are U-phase, V-phase, and W-phase upper switching elements, respectively. Similarly, switching elements Q4, Q5, and Q6 are U-phase, V-phase, and W-phase lower switching elements, respectively. The winding 112 of the motor 106 has a three-phase winding configuration of LU, LV, and LW, and is connected to the U phase, the V phase, and the W phase, respectively.

  The control circuit 4 includes a duty detection means 6, a drive means 7, a rotation speed detection means 8, a magnetic sensor 9, a frequency generation means 10, an amplitude voltage detection means 11, and a rotation direction determination means 12.

  The duty detection means 6 determines the on / off period of the PWM cycle from the PWM signal output as the speed command signal from the external control circuit 5, and calculates the on / off ratio, that is, the duty.

  Hereinafter, a description will be given with reference to FIG. FIG. 3 shows a PWM signal output from the external control circuit 5 as a speed command signal.

  For example, FIG. 3A is a PWM signal output as a forward rotation speed command signal from the external control circuit 5, and the pulse signal cycle is constant and the pulse width is varied to obtain a speed command signal. For example, the pulse period T is 1 ms, and is turned on when the amplitude voltage is 5 V, and turned off when the amplitude voltage is 0 V. When the ON period is Ton and the OFF period is Toff, the ratio of ON to OFF, that is, the duty DUTY is obtained by Equation 1.

  The duty DUTY when the on period Ton and the off period Toff are equal is 0.5.

FIG. 3B shows a PWM signal output as a reverse rotation speed command signal from the external control circuit 5. The pulse signal cycle is constant and the pulse width is varied to obtain a speed command signal. For example, the pulse period T is 1 ms, and is turned on when the amplitude voltage is 12V and turned off when the amplitude voltage is 0V. Assuming that the on period is Ton and the off period is Toff, the ratio of on to off, that is, the duty DUTY can be similarly obtained from Equation 1.

  The drive means 7 performs PWM control based on the duty DUTY detected by the duty detection means 6, and varies the on-time width of the PWM control, that is, the duty, and repeatedly turns each switching element on and off. By arbitrarily varying the duty cycle, an arbitrary voltage (sine wave AC voltage) proportional to the ON pulse width is applied to the brushless DC motor 103.

  A sinusoidal AC voltage is supplied to the windings LU, LV, LW of the winding 112 of the stator 108, and the motor 106 rotates.

  The rotational speed detection means 8 detects the relative position of the rotor 107 with respect to the stator 108 by using the outputs of the three magnetic sensors 9, and detects the N and S poles of the permanent magnet applied to the rotor 107. The number of rotations and the direction of rotation of the motor 106 are detected from the switching of the magnetic poles.

  For example, when the output of the magnetic sensor 9 when the rotor 107 of the motor 106 makes one revolution is 4 pulses per revolution, the number of revolutions of the motor 106 can be obtained by obtaining the number of pulses per unit time. For example, when the number of pulses is 100 pulses per second, the rotation speed of the motor 106 is 400 rotations.

  The frequency generation means 10 outputs a rotation speed pulse to the external control circuit 5 based on the rotation speed obtained by the rotation speed detection means 8. This rotation speed pulse is proportional to the rotation speed.

  The external control circuit 5 detects the current rotation state of the motor 106 based on the rotation number pulse, and outputs a speed command signal to the control circuit 4 so as to obtain a predetermined rotation speed, thereby speed feedback control. It is carried out.

  The amplitude voltage detecting means 11 compares the amplitude voltage of the PWM signal output as the speed signal with a predetermined first threshold voltage and second threshold voltage. When the amplitude voltage is equal to or higher than the first threshold value, the forward rotation command signal is output with the same ON / OFF cycle as the speed signal. When the amplitude voltage is greater than or equal to the second threshold value, the reverse rotation command signal is output with the same ON / OFF cycle as the speed signal.

  Hereinafter, a description will be given with reference to FIGS. 4 and 5.

  FIG. 4 is a diagram showing a state in which the forward rotation speed command signal output by the amplitude voltage detection means is output, and FIG. 5 is a state in which the reverse rotation speed command signal output by the amplitude voltage detection means is output. A diagram is shown.

The speed command signal is an on / off PWM signal having an amplitude voltage of 5V. The first threshold voltage is set to a voltage less than the amplitude voltage of 5V. When a speed command signal having an amplitude voltage of 5 V is input, when the speed command signal is on, the amplitude voltage is equal to or higher than the first threshold voltage, and the forward rotation command signal is turned on. When the speed command signal is off, it becomes less than the first threshold voltage, and the normal rotation command signal is turned off. When the forward rotation command signal is on, a waveform with an amplitude voltage of 5V is generated. When off, a waveform with an amplitude voltage of 0 V is generated. The second threshold voltage is set to a voltage not lower than the amplitude voltage of 5V and lower than the amplitude voltage of 12V. When a speed command signal having an amplitude voltage of 5 V is input, when the speed command signal is on, the amplitude voltage is less than the second threshold value, and the reverse rotation command signal is turned off. When the speed command signal is OFF, it becomes less than the second threshold voltage, and the reverse rotation command signal is turned OFF. When the reverse rotation command signal is on, a waveform with an amplitude voltage of 12V is generated. When the reverse rotation command signal is off, a waveform with an amplitude voltage of 0V is generated. However, when a speed command signal with an amplitude voltage of 5V is input, the off is continued. Thus, a signal having an amplitude voltage of 0V is generated.

  The rotation direction determination unit 12 determines the rotation direction in which the motor 106 is rotated from the normal rotation speed command signal and the reverse rotation speed command signal generated by the amplitude voltage detection unit 11.

  The operation will be described below with reference to the flowchart for determining the rotation direction in FIG.

  In the forward rotation command signal and the reverse rotation command signal, it is determined whether or not each command signal is an on / off PWM waveform. In Steps 1 and 2, when there is a rising edge of the forward rotation command signal and there is no rising edge of the reverse rotation command signal, that is, in the case of Step 3, the rotation direction of the motor 106 is assumed to be forward rotation.

  When there is a rising edge of the normal rotation command signal and there is a rising edge of the reverse rotation command signal, that is, in the case of step 4, the rotation direction of the motor 106 is reverse rotation.

  When there is no rising edge of the forward rotation command signal, that is, in the case of step 5, the rotation direction of the motor 106 is set to forward rotation.

  The drive unit 7 supplies a sinusoidal AC voltage to the windings LU, LV, LW of the winding 112 of the motor 106 so as to rotate in the rotation direction determined by the rotation direction determination unit 12.

  The frequency generation means 10 outputs a rotation speed pulse to the external control circuit 5 based on the rotation speed obtained by the rotation speed detection means 8. This rotation speed pulse is proportional to the rotation speed.

  The external control circuit 5 detects the current rotation state of the motor 106 based on the rotation number pulse, and outputs a speed command signal to the control circuit 4 so as to obtain a predetermined rotation speed, thereby speed feedback control. It is carried out.

  The frequency generation means 10 generates a frequency generation signal with a first amplitude voltage when the motor 106 rotates in the forward rotation direction, and generates a frequency generation signal with the second amplitude voltage when rotating in the reverse rotation direction. By generating a frequency generation signal and switching the amplitude voltage of the frequency generation signal, the rotation direction and the rotation speed of the motor 106 are simultaneously transmitted.

  Hereinafter, a description will be given with reference to FIG. FIG. 7 shows the frequency generation signal output from the frequency generation means 10. FIG. 7A shows a frequency generation signal during forward rotation, and FIG. 7B shows a frequency generation signal during reverse rotation.

  The frequency generation unit 10 generates a frequency generation signal based on the rotation number and rotation direction of the motor 106 output from the rotation number detection unit 8.

  For example, when the motor 106 is rotating once in the forward rotation direction, when the motor 106 rotates once, a 4-pulse signal is output at the first amplitude voltage 5V. When the rotation speed increases, the number of pulses per rotation increases, and when the rotation speed decreases, the number of pulses per rotation decreases.

  In the case where the motor 106 is rotating once in the reverse rotation direction, for example, when the motor 106 rotates once, a 4-pulse signal is output at the first amplitude voltage 12V. When the rotation speed increases, the number of pulses per rotation increases, and when the rotation speed decreases, the number of pulses per rotation decreases.

  With the above configuration, by switching the amplitude voltage of the frequency generation signal, the rotation direction and the rotation speed of the brushless DC motor can be simultaneously transmitted without increasing the number of lead wires that transmit the rotation direction command signal for switching the rotation direction. Can do.

  Further, the frequency generation means 10 is configured to generate a frequency generation signal with the first amplitude voltage when the motor 106 is stopped.

  Hereinafter, a description will be given with reference to FIG. FIG. 8 shows the frequency generation signal at the time of stop output from the frequency generation means 10.

  The frequency generation unit 10 generates a frequency generation signal based on the rotation number and rotation direction of the motor 106 output from the rotation number detection unit 8.

  For example, when the motor 106 is stopped, a 0-pulse signal is output at the first amplitude voltage 5V.

  With the above configuration, the rotation direction and the rotation number of the rotor can be transmitted simultaneously without increasing the number of lead wires.

  Moreover, it is set as the ceiling fan carrying the brushless DC motor with a built-in circuit.

  Hereinafter, a description will be given with reference to FIG. FIG. 9 shows a ceiling fan equipped with a brushless DC motor with a built-in circuit.

  An illuminator 102 is provided below the ceiling fan 13, and the built-in brushless DC motor 1 and the external control circuit 5 are built in the ceiling fan 13, and the blades 105 attached to the built-in brushless DC motor 1 are rotated.

  With the above configuration, a ceiling fan mounted with a small and controllable brushless DC motor with a good controllability that can easily switch the rotation direction of the blades without increasing the number of lead wires.

The brushless DC motor with a built-in circuit according to the present invention and the ceiling fan equipped with the brushless DC motor with a built-in circuit are small and controllable brushless DC motors that can easily change the rotation direction of the blades without increasing the number of circuit lead wires. It is useful as an installed ceiling fan.

DESCRIPTION OF SYMBOLS 1 Brushless DC motor with built-in circuit 2 Printed circuit board 3 Signal lead wire 4 Control circuit 5 External control circuit 6 Duty detection means 7 Drive means 8 Rotation speed detection means 9 Magnetic sensor 10 Frequency generation means 11 Amplitude voltage detection means 12 Rotation direction determination means 13 Ceiling fan

Claims (4)

A rotor with permanent magnets,
A stator with three-phase winding;
A DC voltage input from a DC power source is drawn into a plurality of upper switching elements connected to the positive side and a plurality of lower switching elements connected to the negative side via a capacitor, and the upper switching element and the lower switching element An inverter circuit for applying a driving voltage to the three-phase winding by switching elements;
A control circuit for controlling the operation of the inverter circuit;
A mold shell covering the stator, the inverter circuit, and the control circuit;
A power line for supplying power,
A speed command signal lead wire for outputting a speed command signal for controlling the rotational speed of the power line and the rotor, and
A brushless DC motor with a built-in circuit,
The control circuit includes:
A frequency generation signal means for generating a frequency generation signal with a predetermined amplitude voltage based on the number of rotations of the rotor;
An amplitude voltage detection means for comparing the amplitude voltage of the speed command signal with a predetermined first threshold voltage and a second threshold voltage to determine the amplitude voltage;
When the result of the amplitude voltage detected by the amplitude voltage detecting means is not less than the first threshold value and less than the second threshold value, the rotation direction is determined to be normal rotation, and the result is not less than the first threshold value. And when it is greater than or equal to the second threshold value, the rotation direction determining means for reversely rotating the rotation direction,
A brushless DC motor with a built-in circuit, wherein the rotation direction command and the rotation number command of the rotor are simultaneously transmitted by switching the amplitude voltage of the speed command signal. The frequency generation signal means generates a frequency generation signal with a first amplitude voltage that is greater than or equal to the first threshold value and less than the second threshold value when the rotor is rotating in a forward rotation. And generating a frequency generation signal with a second amplitude voltage that is greater than or equal to the first threshold and greater than or equal to the second threshold when the rotor is rotating in reverse rotation, The brushless DC motor with a built-in circuit according to claim 1, wherein the rotation direction and the number of rotations of the rotor are simultaneously transmitted by switching the amplitude voltage of the rotor. The frequency generation signal means generates a frequency generation signal with a first amplitude voltage when the rotor is stopped, and simultaneously transmits a rotation direction and a rotation speed of the rotor. 1 is a brushless DC motor with a built-in circuit. A ceiling fan on which the brushless DC motor with a built-in circuit according to any one of claims 1 to 3 is mounted.

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