In liquid, the Helmholtz resonance container 110 in order to be able to measure the volume of an object without contact by using a Helmholtz resonator includes a container 130 having a sealable opening 132, a hollow portion of the interior of the container 130 It includes a lower end communicating with a neck portion 138 having an upper end which is open, disposed at the upper end of the neck portion 138, and a cover member 140 having an opening communicating with the interior of the neck portion 138. Edge of the opening 112 of the cover member 140, nearer the wall thickness in the opening portion becomes thinner, forming the lead portion 152 for voice generation. Sound is generated by the read unit 152 by applying a water flow from the water pipe 118 to the lead 152, the Helmholtz resonance is generated in the container 110 in response to the speech. Is previously put an object in the container 130, by examining the peak frequency of the Helmholtz resonator, it is possible to measure the volume of an object by a predetermined functional relationship.液体中で、ヘルムホルツ共鳴を用いて対象物の体積を非接触で計測できるようにするためのヘルムホルツ共鳴容器110は、密閉可能な開口部132を有する容器130と、容器130の内部の中空部分と連通する下端と、開口する上端とを持つネック部138と、ネック部138の上端に設けられ、ネック部138の内部に連通する開口部を持つカバー部材140とを含む。カバー部材140の開口部112の縁部が、当該開口部に近くなるほど肉厚が薄くなる、音声発生のためのリード部152を形成している。リード部152に送水管118から水流をあてることによりリード部152により音声が発生し、この音声に応答して容器110でヘルムホルツ共鳴が発生する。容器130内に対象物を入れておき、ヘルムホルツ共鳴のピーク周波数を調べることで、所定の関数関係により対象物の体積を計測できる。
