Mollerup automatic pump lubricator

Mollerup automatic pump lubricator for steam engines

This is an example of a positively driven lubricator patented in France by A. M. Mollerup in 1881. It is employed extensively on the Continent, and a modified form is manufactured in this country. It consists of a lower vessel to contain oil, fitted with a hollow plunger or piston, which is actuated by an arrangement of ratchet, worm and screw gearing. The upper end of the piston forms a nut for a square-threaded screw which has a loose worm wheel on its upper end. This wheel gears with a worm driven by a ratchet wheel, the long ratchet arm obtaining its motion by its attachment to a reciprocating part of the engine. Thus at every stroke of the engine a slight turn is imparted to the square-threaded screw, and this, being fixed in position, causes the nut, i.e., the piston, to descend and force out oil into the distributing pipe, which is attached to the upper part of the oil cylinder. The rate of oil feed can be adjusted to suit the requirements by moving a sliding block on the ratchet arm, When a wing nut above the plunger screw is tightened, the worm wheel and the screw rotate as one, but when this nut is loose, the worm wheel revolves freely on the screw and the plunger can be raised or lowered by turning the handle at the top of the lubricator. To fill the lubricator, the wing nut is slackened and the plunger is drawn to the top of its stroke. Oil can then be poured into the lower vessel through the cup at the side. The rotation of the plunger is prevented by a piece of bent wire, U-shaped at its upper end, which is guided by a vertical fixed wire rod. The screw is only just long enough to allow the plunger to reach its lowest position and empty the vessel of oil; any further rotation then winds the screw out of the plunger.