초록 ▼

An improved absolute position detection method is provided for a stroke sensing cylinder which includes a magnetic scale detecting step for obtaining a plurality of sine wave form voltages having different phases using a magnetic sensor unit in accordance with a driving operation of the cylinder. A

An improved absolute position detection method is provided for a stroke sensing cylinder which includes a magnetic scale detecting step for obtaining a plurality of sine wave form voltages having different phases using a magnetic sensor unit in accordance with a driving operation of the cylinder. A wave form generation step is also provided for converting the sine wave form voltage obtained in the magnetic scale detection step into a square wave form and generating a triangle wave form having the same period as the thusly converted square wave form. A first absolute position value detection and stroke direction judging step is then provided for judging a first absolute position value and stroke direction of the cylinder using a pair of square and triangle wave forms generated in the wave form generation step. Lastly, a second absolute position value computation and storing step is provided for computing and storing a second absolute position value having a predetermined value based on the first absolute position value. The method of the present invention is directed to detecting a magnetic flux change of a magnetic scale using a plurality of magnetic sensors. The magnetic scale is disposed along the cylinder rod and includes at least one different magnetic scale processing period contained within a regularly protruded and recessed portion. Signal-processing is achieved using a microprocessor and a 1/N-dividing counter. The thusly signal-processed wave forms are counted and an absolute position and stroke direction is determined.

대표청구항 ▼

[ What is claimed is:] [1.] In a method for detecting a magnetic flux change of a magnetic scale using a plurality of magnetic sensors with respect to the cylinder rod including at least one different magnetic scale processing period in a regularly protruded and recessed portion, signal-processing u

[ What is claimed is:] [1.] In a method for detecting a magnetic flux change of a magnetic scale using a plurality of magnetic sensors with respect to the cylinder rod including at least one different magnetic scale processing period in a regularly protruded and recessed portion, signal-processing using a microcomputer and a 1/N-dividing counter, counting the thusly signal-processed wave forms, and judging an absolute position and direction with respect to a stroke of a cylinder, the improved method comprising the steps of:a magnetic scale detecting step for detecting a plurality of sine wave form voltages having different phases using a magnetic sensor unit in accordance with a driving operation of the cylinder;a wave form generation step for converting said plurality of sine wave form voltages obtained in said magnetic scale detection step into a plurality of corresponding square wave forms, said wave form generation step further generating a plurality of triangle wave forms, each of said plurality of triangle wave forms having the same period as a corresponding one of said plurality of square wave forms;a first absolute position value detection and stroke direction judging step for judging a first absolute position value and stroke direction of the cylinder using a pair of said plurality of square and triangle wave forms generated in said wave form generation step; anda second absolute position value computation and storing step for computing and storing a second absolute position value having a predetermined value based on the first absolute position value.