The oiler has a sheet metal looks like a daisy with with the petals in hollows folded up towards the center which are adjusted in a part of the hat which is similar by machining . A sensitive effort is felt when one turns the hat to reason des compressions / laxities of the spring. These oilers date 1930.

these patters are exceptional grease cups for service where vibration is especially severe. The pins prohibit to unscrew the cap .Also we must block the foot in its lowest position.

French greaser LEFEBVRE of the 1920.  F and B are in the same disk of steel. The spring pushes disk C against the disk B + F . It takes an important effort of rotation to go out "b" "c".
link for catalog of LEFEBVRE 1922

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