Piston having a restrictable opening (e.g., apertured plate) in a fixed volume chamber:
(under subclass 266) Internal resistance motion retarder wherein restraining effort varies in accordance with the relationship between a passage for fluid medium and an element modifying the size of the passage within a cylinder having a predetermined size.
SEE OR SEARCH THIS CLASS, SUBCLASS:
319.2, for varying orifice size using a hand or hand tool in a variable volume chamber.
SEE OR SEARCH CLASS
267, Spring Devices,
140.11+, for a resilient shock absorber including energy absorbing means having an orifice plate.
