Patent ID: 6733423
Filing Date: 2004-05-11
Classification: A63B

Abstract:
A speed control device of a treadmill, said speed control device being arranged in a certain position on a controlling panel of the treadmill, said speed control device comprising a transmitter, a receiver, a transmitter end circuit and a receiver end circuit, wherein:the transmitter and the receiver are mounted on the controlling panel of the treadmill and directed to rear end of the treadmill, the transmitter serving to generate and transmit ultrasonic wave, while the receiver serving to receive reflected ultrasonic wave; the transmitter end circuit is disposed in the controlling panel and connected with a CPU and the transmitter inside the controlling panel, the transmitter end circuit having an oscillating IC circuit and an analog-digital converting circuit, the oscillating IC circuit serving to oscillate the ultrasonic wave generated by the transmitter to high frequency, the analog-digital converting circuit serving to convert the digital signal of the CPU into analog signal; and the receiver end circuit is disposed in the controlling panel and connected with the CPU and the receiver inside the controlling panel, the receiver end circuit having an amplifying circuit and an analog-digital converting circuit, the amplifying circuit serving to amplify the reflected ultrasonic wave received by the receiver into high frequency, the analog-digital converting circuit serving to convert the reflected analog signal into digital signal and send the signal to the CPU.