Engineering mechanical speedometer circuit

Abstract

The invention relates to an engineering mechanical speedometer circuit. The engineering mechanical speedometer circuit comprises a power supply voltage-stabilizing circuit, a power supply state detection circuit, a signal input circuit, and a master control circuit, digital frequency measurement of input signals is performed through a single-chip microcomputer, a moving magnetic type gauge head or a stepping motor type gauge head is directly driven through a single-chip microcomputer I / O in a PWM mode after software operation, a mileage counter and an electronic speedometer are combined together, the input signals are counted through software, and the accumulated mileage is displayed through a LCD. The engineering mechanical speedometer circuit is advantageous in that digital frequency measurement and software conversion are employed so that the conversion precision is high, and the adjusting range is wide; the indication positions of scales can be corrected one by one during debugging so that the indication linearity of the meter is good; a gauge head driving circuit is cancelled, and the gauge head is driven by employing the single-chip microcomputer I / O port so that the circuit cost is reduced; the form of the driven gauge head can be randomly replaced by adjusting software setting options so that the usage is more flexible; and most circuit hardware is shared so that the size is small, and the cost is low.

Description

technical field [0001] The invention relates to a construction machinery speedometer circuit, in particular to an electronic speedometer circuit with a mileage counter based on single-chip microcomputer control technology and used to measure the driving speed and mileage when the construction machinery is working. Background technique [0002] With the improvement of domestic construction machinery technology, the application of electronic speedometer is gradually being popularized. Electronic speedometers for construction machinery generally use the method of measuring the sine wave frequency signal output by the magnetic induction sensor on the gearbox housing, and converting the frequency signal into the deflection angle of the pointer installed on the meter head to realize the vehicle speed indication . The current electronic speedometer circuit commonly used in construction machinery is mainly composed of analog circuits. The principle is to integrate the frequency sig...

AI Technical Summary

Problems solved by technology

[0003] The general solution of the above electronic speedometer has the shortcomings of low measurement accuracy of the analog circuit, small adjustment range of the potentiometer, and no compensation measures for the non-linearity of the meter head. In addition, the mileage counter is designed as a separate component, which increases the volume and use cost when used.

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