Motor driving circuit based on ultrasonic sensor

Abstract

The utility model discloses a motor drive circuit based on an ultrasonic sensor, which relates to the field of motor drive control and comprises an external connection port used for providing a port for connection between an external device and a circuit; according to the motor driving circuit based on the ultrasonic sensor, the distance between a user and the electric fan is sensed in real time through the distance detection module embedded in the electric fan, and the distance detection module detects the distance between the user and the electric fan through the ultrasonic sensor, converts the distance into a digital signal through AD processing and transmits the digital signal to the circuit driving chip; after receiving the corresponding signal, the circuit driving chip analyzes and processes the signal to generate a corresponding instruction for controlling the start and stop of the electric fan and adjusting the electric fan; and after a corresponding instruction is received, the driving circuit main control chip generates a corresponding PWM signal to control the start and stop of the electric fan or the rotating speed of the electric fan, so that the functions of automatic start and stop and automatic rotating speed regulation are achieved.

Description

Technical Field

[0001] The utility model relates to a motor drive control technology, in particular to a motor drive circuit based on an ultrasonic sensor. Background Art

[0002] Traditional electric fans generally run at a constant speed and cannot automatically adjust the speed according to actual conditions. This driving method often easily leads to excessive use of energy, which in turn requires users to bear unnecessary usage costs and reduce their willingness to use.

[0003] Most traditional electric fans change the motor speed by switching gears and run at a constant speed. They are unable to perform corresponding speed control according to actual conditions, which brings unnecessary trouble to their use.

[0004] Traditional electric blowers usually use mechanical buttons to control the start and stop and gear switching of the motor. Therefore, frequent start and stop or gear switching can easily cause damage to the mechanical buttons, making it difficult for users to perform corresponding operations or even causing the motor to fail to start.

[0005] Traditional electric fans usually run at a constant speed in different gears and cannot adjust the speed according to the user's actual usage scenario. Utility Model Content

[0006] The purpose of the utility model is to provide a motor drive circuit based on an ultrasonic sensor to solve the above-mentioned deficiencies in the prior art.

[0007] In order to achieve the above object, the utility model provides the following technical solution: a motor drive circuit based on an ultrasonic sensor, comprising:

[0008] External connection pins, the external connection pins are used to provide ports for connecting external devices to the circuit;

[0009] An ultrasonic sensor, wherein the ultrasonic sensor is used for distance detection and is connected to a driving circuit;

[0010] A single-phase coil, wherein the single-phase coil is connected to a drive circuit;

[0011] A driving circuit, wherein the driving circuit is used to drive the ultrasonic sensor;

[0012] An external power supply is used to provide an external power supply for the circuit.

[0013] Furthermore, the driving circuit includes a driving chip U1, a chip filter capacitor C1, an FG current limiting resistor R1, a distance detection feedback pull-down resistor R2, a distance detection feedback filter capacitor C2 and a chip pull-down resistor R3.

[0014] Furthermore, pin 1 of the driving chip U1 is connected to the positive pole of the power supply VCC, pin 2 of the driving chip U1 is connected to the outside through the FG current limiting resistor R1, pin 3 of the driving chip U1 is the chip trigger signal output, connected to the Trig end of the ultrasonic sensor, pin 4 of the driving chip U1 is the output echo signal receiving end, connected to the Echo end of the ultrasonic sensor, pin 5 of the driving chip U1 is connected to the negative pole of the power supply GND through a pull-down resistor R3, pin 6 of the driving chip U1 is connected to one end of the single-phase coil, pin 7 of the driving chip U1 is connected to the other end of the single-phase coil, and pin 8 of the driving chip U1 is connected to the negative pole of the power supply GND.

[0015] Furthermore, one end of the chip filter capacitor C1 is connected to the positive power supply electrode VCC, and the other end of the chip filter capacitor C1 is connected to the negative power supply electrode GND.

[0016] Furthermore, one end of the distance detection feedback signal filter capacitor C2 is connected to pin No. 4 of the chip, and the other end of the distance detection feedback signal filter capacitor C2 is connected to the negative electrode GND of the power supply.

[0017] Furthermore, the external connection pins include port P1, the J1 pin of the port P1 is the positive power input pin, the J2 pin of the port P1 is the negative power input pin, the J3 pin of the port P1 is the motor speed feedback FG pin, and the J4 pin of the port P1 is the +5V input pin.

[0018] Compared with the prior art, the utility model provides a motor drive circuit based on an ultrasonic sensor. By utilizing a distance detection module embedded inside the electric blower, the distance detection module detects the distance between the user and the electric blower through the ultrasonic sensor, converts the detected distance into a digital signal through AD processing, and transmits it to the circuit drive chip. After receiving the corresponding signal, the circuit drive chip generates corresponding instructions for controlling the start and stop of the electric blower and adjusting the electric blower through analysis and processing. After receiving the corresponding instruction, the main control chip of the drive circuit will generate a corresponding PWM signal to control the start and stop of the electric blower or the speed of the electric blower, thereby achieving the functions of automatic start and stop and automatic speed adjustment. When the distance between the user and the electric blower reaches a certain distance, the electric blower will start automatically. As the distance between the user and the electric blower gets closer, the motor will adjust the speed accordingly according to the mode set in advance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present utility model. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0020] Figure 1 The present invention is a schematic diagram of the overall structure of an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings.

[0022] See also Figure 1 , a motor driving circuit based on an ultrasonic sensor, comprising:

[0023] External connection pins, which are used to provide ports for connecting external devices to circuits;

[0024] Ultrasonic sensor, the ultrasonic sensor is used for distance detection, and the ultrasonic sensor is connected to the driving circuit;

[0025] A single-phase coil, wherein the single-phase coil is connected to a driving circuit;

[0026] A driving circuit, the driving circuit is used to drive the ultrasonic sensor;

[0027] External power supply, the external power supply is used to provide external power to the circuit.

[0028] The driving circuit includes a driving chip U1, a chip filter capacitor C1, an FG current limiting resistor R1, a distance detection feedback pull-down resistor R2, a distance detection feedback filter capacitor C2 and a chip pull-down resistor R3.

[0029] Pin 1 of the driver chip U1 is connected to the positive pole of the power supply VCC, pin 2 of the driver chip U1 is connected to the outside through the FG current limiting resistor R1, pin 3 of the driver chip U1 is the chip trigger signal output, connected to the Trig end of the ultrasonic sensor, pin 4 of the driver chip U1 is the output echo signal receiving end, connected to the Echo end of the ultrasonic sensor, pin 5 of the driver chip U1 is connected to the negative pole of the power supply GND through the pull-down resistor R3, pin 6 of the driver chip U1 is connected to one end of the single-phase coil, pin 7 of the driver chip U1 is connected to the other end of the single-phase coil, and pin 8 of the driver chip U1 is connected to the negative pole of the power supply GND.

[0030] One end of the chip filter capacitor C1 is connected to the positive electrode VCC of the power supply, and the other end of the chip filter capacitor C1 is connected to the negative electrode GND of the power supply.

[0031] One end of the distance detection feedback signal filter capacitor C2 is connected to pin 4 of the chip, and the other end of the distance detection feedback signal filter capacitor C2 is connected to the negative electrode GND of the power supply.

[0032] The external connection pins include port P1, the J1 pin of port P1 is the positive power input pin, the J2 pin of port P1 is the negative power input pin, the J3 pin of port P1 is the motor speed feedback FG pin, and the J4 pin of port P1 is the +5V input pin.

[0033] The ultrasonic sensor is driven by an external 5V input. The driver chip sends a trigger signal to the ultrasonic sensor through pin 3. After receiving the trigger signal, the ultrasonic sensor will send a certain number of cyclic pulses and detect whether there is a radio wave returning. When a radio wave is detected, a high level is output through the Echo port, and the duration of the high level is the time from the ultrasonic wave being sent to the return. That is to say, the distance D = VT / 2, V is the speed of sound, and T is the duration of the high level. After the ultrasonic sensor Echo outputs a high level, it inputs a voltage signal to pin 3 of the chip through a resistor divider. The chip adjusts the motor drive PWM signal by detecting the voltage signal to control the motor speed and power. When the detection distance becomes closer, the duration of the high level output by the ultrasonic sensor Echo pin becomes shorter, and the duty cycle of the PWM signal that adjusts the motor drive is reduced, thereby reducing the motor speed to a suitable range.

[0034] When the detection distance becomes longer, the high level duration of the ultrasonic sensor Echo pin output becomes longer, and the duty cycle of the PWM signal that adjusts the motor drive increases, so that the motor speed rises to the appropriate range. At the same time, the chip calculates internally through the software and outputs the speed feedback signal FG through the chip 2 pin.

[0035] The calculation formula of the speed feedback signal FG is:

[0036] FG signal frequency f1=n*p / 60

[0037] Where n is the motor speed and p is the number of motor pole pairs.

[0038] Working principle: First, the distance detection module embedded in the electric fan is used to sense the distance between the user and the electric fan in real time. The distance detection module detects the distance between the user and the electric fan through an ultrasonic sensor, and then converts it into a digital signal through AD processing and transmits it to the circuit driver chip. After receiving the corresponding signal, the circuit driver chip generates the corresponding control instructions for starting and stopping the electric fan and adjusting the electric fan after analysis and processing; after receiving the corresponding instructions, the main control chip of the drive circuit will generate the corresponding PWM signal to control the start and stop of the electric fan or the speed of the electric fan, so as to achieve the functions of automatic start and stop and automatic speed adjustment. When the distance between the user and the electric fan reaches a certain distance, the electric fan will start automatically; as the distance between the user and the electric fan gets closer, the motor will adjust the speed accordingly according to the pre-set mode.

[0039] The above only describes some exemplary embodiments of the present invention by way of illustration. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A motor drive circuit based on an ultrasonic sensor, characterized in that: include: External connection pins, the external connection pins are used to provide ports for connecting external devices to the circuit; An ultrasonic sensor, wherein the ultrasonic sensor is used for distance detection and is connected to a driving circuit; A single-phase coil, wherein the single-phase coil is connected to a drive circuit; A driving circuit, wherein the driving circuit is used to drive the ultrasonic sensor; An external power supply is used to provide an external power supply for the circuit.

2. The motor drive circuit based on ultrasonic sensor according to claim 1, characterized in that: The driving circuit includes a driving chip U1, a chip filter capacitor C1, an FG current limiting resistor R1, a distance detection feedback pull-down resistor R2, a distance detection feedback filter capacitor C2 and a chip pull-down resistor R3.

3. The motor drive circuit based on ultrasonic sensor according to claim 2, characterized in that: Pin 1 of the driver chip U1 is connected to the positive pole of the power supply VCC, pin 2 of the driver chip U1 is connected to the outside through the FG current limiting resistor R1, pin 3 of the driver chip U1 is the chip trigger signal output, connected to the Trig end of the ultrasonic sensor, pin 4 of the driver chip U1 is the output echo signal receiving end, connected to the Echo end of the ultrasonic sensor, pin 5 of the driver chip U1 is connected to the negative pole of the power supply GND through a pull-down resistor R3, pin 6 of the driver chip U1 is connected to one end of the single-phase coil, pin 7 of the driver chip U1 is connected to the other end of the single-phase coil, and pin 8 of the driver chip U1 is connected to the negative pole of the power supply GND.

4. The motor drive circuit based on ultrasonic sensor according to claim 3, characterized in that: One end of the chip filter capacitor C1 is connected to the positive electrode VCC of the power supply, and the other end of the chip filter capacitor C1 is connected to the negative electrode GND of the power supply.

5. The motor driving circuit based on ultrasonic sensor according to claim 1, characterized in that: One end of the distance detection feedback signal filter capacitor C2 is connected to the chip pin No. 4, and the other end of the distance detection feedback signal filter capacitor C2 is connected to the negative electrode GND of the power supply.

6. The motor drive circuit based on ultrasonic sensor according to claim 1, characterized in that: The external connection pins include port P1, the J1 pin of the port P1 is the positive power input pin, the J2 pin of the port P1 is the negative power input pin, the J3 pin of the port P1 is the motor speed feedback FG pin, and the J4 pin of the port P1 is the +5V input pin.

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