摘要 |
<p>An air-oil full hydraulic reservoir tank of the type used with a vehicle lift system. The tank includes a tank wall forming the tank and a discharge pipe within the tank. The discharge pipe includes an inlet tube portion, an outlet tube portion, each extending through an upper portion of the tank, and a connection, such as a connecting loop portion or a passageway in a casting, within a lower portion of the tank, that joins the lower ends of the inlet and outlet tube portions. A low oil control mechanism within the tank blocks the flow of hydraulic oil from the inlet tube portion to the outlet tube portion when the level of the oil is below a predetermined level, thereby preventing the flow of air through the outlet tube. The inlet tube may be perforated, and the low oil control mechanism may be a float within the inlet tube that rests on a valve seat to block the flow of air into the outlet tube. A connecting pipe joins the reservoir tank to a hydraulic lift cylinder, with interposed control valves. The hydraulic lift cylinder raises and lowers a piston as air is forced into or bled from the reservoir tank, forcing oil from the reservoir tank into and from the lift cylinder.</p> |