Hydraulic excavator and method for measuring stroke of hydraulic cylinder of hydraulic excavator

摘要

A hydraulic excavator includes a base body portion, a movable portion, a hydraulic cylinder, a position sensor, a rotary encoder, and a control unit. The rotary encoder includes a light emitting unit, a light receiving unit, and a disk unit having a plurality of transmission portions. The control unit measures the stroke length of the hydraulic cylinder by correcting deviation of the stroke length, which is measured by the position sensor, based on the pulse signal output from the rotary encoder. In this way, there can be obtained a hydraulic excavator capable of precisely measuring a stroke length of a hydraulic cylinder driving a work implement, as well as a method for measuring the stroke of the hydraulic cylinder of the hydraulic excavator.

主权项

1. A hydraulic excavator comprising:
a base body portion formed of one of a vehicle main body and a boom; a movable portion supported to be revolvable relative to said base body portion; a hydraulic cylinder supporting said movable portion such that said movable portion is revolvable relative to said base body portion; a position sensor installed on said hydraulic cylinder to measure a stroke length of said hydraulic cylinder; a rotary encoder installed across said base body portion and said movable portion, said rotary encoder including a light emitting unit, a light receiving unit capable of receiving light emitted from said light emitting unit, and a disk unit having a plurality of transmission portions that permit passage of the light emitted from said light emitting unit to said light receiving unit, said disk unit being revolved in synchronization with revolution of said movable portion relative to said base body portion, said light receiving unit outputting, based on the light having passed through said plurality of transmission portions, a pulse signal generated according to an angle of revolution of said disk unit, said angle of revolution of said disk unit being associated with an angle of revolution of said movable portion; and a control unit measuring the stroke length of said hydraulic cylinder by correcting deviation of the stroke length, which is measured by said position sensor, based on said pulse signal output from said rotary encoder.