Two-line liquid dispenser, especially for lubricants of central loss lubrication systems

摘要

The two-pipe liquid dispenser (3) comprises at least one dosing unit (31), the operating cycle of which consists of a filling and a discharge phase, and is connected to a lubrication circuit with an outlet for one lubrication point (51). In the discharge phase, a control fluid is supplied to the control chamber (314) under pressure (p314), and a dose of lubricating fluid is forced out of the dosing chamber (313) toward the lubrication point. There is a negligible pressure drop between the control and dosing chamber. The metering ball (312) is entrained by the liquid stream without the liquid flowing through the annular gap, i.e. the radial clearance (312b) between the ball and its guide. On the outlet side of the dosing chamber, the cylindrical cavity (311) is provided with a valve seat (315), the closing element of which is a ball (312), which preferably simultaneously has the function of a dosing piston. A ball (312) abuts the valve seat (315) at the end of the discharge phase, thus preventing undesired leakage of control fluid from the control chamber to the lubrication point (51).