| 摘要 |
PROBLEM TO BE SOLVED: To constitute a using circuit with RoSH (Restriction of Hazardous Substances) corresponding component in consideration of also an environmental problem; to cancel always automatically an unbalanced component by a stray capacitance or the like, while reducing a power supply noise; and to measure accurately an actual resistance component following a resistance value change corresponding to a strain gage included in a measuring bridge. SOLUTION: This carrier wave type strain measuring device has a constitution divided into two systems, namely, a primary side circuit system including a measuring bridge 11, an input transformer 12 for inputting output from the bridge 11, a cancellation circuit 14 for correcting the output from the bridge with a fed-back compensation amount, and a primary side power source circuit 18; and a secondary side circuit system including a carrier wave amplifying circuit 21 for generating the compensation amount from the output from the measuring bridge 11, a capacity portion phase detection circuit 23, a capacity portion canceling driving circuit 24, a carrier wave oscillation circuit 26, and a secondary side power source 28. The primary side circuit system and the secondary side circuit system are bonded only through a magnetic bonding means and a light signal transmission means which is an optical bonding means, and do not have an electrical connection part. COPYRIGHT: (C)2011,JPO&INPIT
|
