Fluid detection apparatus to detect a quantity of fluid using a vibration

Abstract

A fluid detection apparatus to detect quantity of a fluid having flowability and stored in a casing includes an oscillator disposed outside the casing to output a frequency of an oscillation signal corresponding to a magnetic flux passing through a space near the oscillator, a vibrator made of material effecting the magnetic flux and disposed inside the casing, a vibration trigger disposed inside the casing to vibrate the vibrator, and circuitry to acquire frequency-related information related to the frequency of the oscillation signal output from the oscillator, detect the vibration of the vibrator based on a change of the frequency-related information, determine whether the vibration of the vibrator converges during a convergence-checking time period defined after the vibrator is vibrated by the vibration trigger, and detect the quantity of the fluid in the casing based on a convergence determination result of the vibration of the vibrator.