| 摘要 |
PROBLEM TO BE SOLVED: To provide a compact content quantity estimating device capable of correctly estimating a content quantity of a liquid or a solid in a container, and a content quantity estimation system including the same.SOLUTION: In a liquid quantity estimating device 6 of a vehicle fuel system 1, a piston 30 is provided with a magnet 35, and an airtight cylinder 20 is provided with an electromagnetic coil 41 applying magnetic force to the magnet 35. A coil power source part 42 supplies the electromagnetic coil 41 with an alternating electric current generating a magnetic force that moves the piston 30 in a reciprocating manner in the airtight cylinder 20, and a control part 60 detects a resonance frequency between a reciprocating movement of the piston 30 and an alternating electric current. Then, the control part 60 estimates a liquid quantity in a fuel tank 10 on the basis of the resonance frequency between the reciprocating movement of the piston 30 and the alternating electric current. |
