Patent ID: 7644727

Claim:
A hydraulic fluid reservoir having at least one hydraulic fluid port and comprising: a container having a hollow body with a top, the container having an interior; a means for creating and maintaining an air pocket within the container, the means comprising a conduit having an upper portion extending upwardly from the top of the container and a lower portion extending downwardly from the upper portion within the interior of the container, the conduit having a bottom within the container and a top above the bottom thereof, the conduit having an opening adjacent to the bottom of the conduit, the opening being spaced-apart below the top of the container, the opening being so positioned within the container as to create the air pocket within the container when hydraulic fluid is poured through the conduit to fill the container, the air pocket being trapped in the container between the top of the container and the bottom of the conduit when the container is so filled with hydraulic fluid; and a closure member releasably and sealingly connected to the top of the conduit, the reservoir being sealed apart from said closure member and said at least one port when the closure member is sealingly connected to the top of the conduit, whereby addition of further hydraulic fluid fills the conduit to the top thereof and the conduit overflows if additional hydraulic fluid is added after the top of the conduit is reached by the fluid.