| 摘要 |
PROBLEM TO BE SOLVED: To provide an easy-to-use and inexpensive capacitance type proximity detection sensor for detecting an object being in close proximity by detecting a change in electrostatic capacity, which automatically adjusts its sensitivity in response to changes in the shape of a detection electrode and installation conditions, moreover can deal with electrostatic sparks without adding a new element for dealing with them. SOLUTION: The proximity detection sensor detects from a change in the electrostatic capacity that an object to be detected is in close proximity to the detection electrode. The proximity detection sensor includes: a capacitance measuring means for measuring capacitance with time; a filter value calculation means for outputting a filter value acquired by removing quick change components of each measured value measured with time; a determination value calculation means for calculating and outputting a determination value for proximity detection decided corresponding to the filter value; and a determination means for detecting that the measured value has changed from the filter value by the determination value or above. COPYRIGHT: (C)2010,JPO&INPIT |
