RESERVOIR TANK

To provide a reservoir tank which inhibits air bubbles from flowing to a cylindrical protruding part regardless of arrangement of the protruding part.SOLUTION: In a reservoir tank 10, a reservoir body 11 is formed into a hollow box shape, stores a fluid therein, and includes: a port 12 extending outward from a peripheral wall part 11a2; an upper partition member 13a and a lower partition member 13b (a first partition part 13) which divide the interior into a storage chamber R1 which stores the fluid and a port chamber R2 having a volumetric capacity smaller than the storage chamber R1 and communicating with the port 12; and a first communication passage 14 which is located below a liquid surface of the fluid stored in the storage chamber R1 in a vertical direction and is provided at the lower partition member 13b so as to allow communication between the storage chamber R1 and the port chamber R2. The port chamber R2 and the port 12 are kept in a state that the port chamber R2 and the port 12 are filled with the fluid supplied from the storage chamber R1 through the first communication passage 14.SELECTED DRAWING: Figure 2 【課題】筒状の突出部の配置に拘わらず、突出部に気泡が流れることを抑制するリザーバタンクを提供すること。【解決手段】リザーバタンク１０において、中空箱状に形成され内部にフルードを貯留するリザーバ本体１１は、周壁部１１ａ２の周壁部１１ａ２から外方に向けて延設されたポート１２と、フルードを貯留する貯留室Ｒ１と、貯留室Ｒ１よりも小さい容積を有してポート１２と連通しているポート室Ｒ２と、に区画する上部仕切部材１３ａ及び下部仕切部材１３ｂ（第一仕切部１３）と、貯留室Ｒ１に貯留されたフルードの液面よりも鉛直方向にて下方に位置しており、貯留室Ｒ１とポート室Ｒ２とを連通するように下部仕切部材１３ｂに設けられた第一連通路１４と、を有し、ポート室Ｒ２及びポート１２が第一連通路１４を介して貯留室Ｒ１から供給されるフルードで充填された状態で保持される。【選択図】図２