METHOD OF CONTROLLING ROTATIONAL SPEED OF MOTOR OF ELECTRIC BED

摘要

A method of controlling a rotational speed of a motor of an electric bed includes the following steps. (A) Use a sensor to detect rotation of the motor, set a predetermined rotational speed of the motor in a microcontroller, and use the microcontroller to calculate actual rotational speeds of the motor. (B) Use the microcontroller to calculate an average actual rotational speed of the motor at each of sampling time points in a predetermined period. (C) Use the microcontroller to compare the average actual rotational speed of the motor with the predetermined rotational speed to obtain a difference signal. (D) Input the difference signal to a driver circuit to adjust the rotational speed of the motor until the average actual rotational speed of the motor is equal to the predetermined rotational speed. In this way, the motor of the electric bed can approximately rotate in the predetermined rotational speed.

主权项

1. A method of controlling a rotational speed of a motor of an electric bed, the motor being driven and controlled by a driver circuit, the method comprising the steps of:
(A) using a sensor to detect rotation of the motor to output a sensing signal, setting a predetermined rotational speed of the motor in a microcontroller, and using the microcontroller to calculate actual rotational speeds of the motor according to the sensing signal while the motor is in operation; (B) using the microcontroller to calculate an average actual rotational speed of the motor at each of sampling time points in a predetermined period, wherein the average actual rotational speed equals a total rotational speed divided by an accumulative time from beginning of the predetermined period till the sampling time point when the average actual rotational speed is calculated, and the total rotational speed is a summation of the actual rotational speeds obtained from the beginning of the predetermined period till the sampling time point when the average actual rotational speed is calculated; (C) using the microcontroller to compare the average actual rotational speed of the motor obtained at said each of the sampling time points with the predetermined rotational speed to obtain a difference signal; and (D) inputting the difference signal obtained at said each of the sampling time points to the driver circuit to adjust the rotational speed of the motor until the average actual rotational speed of the motor is equal to the predetermined rotational speed.