The first documented invention of the doorhandle appears in U.S. Patent entries for the year 1878 when a patent for enhancements on a device that closes the door was issued to a person named Osbourn Dorsey. The traditional door knob has a bolt or spindle running through it which sits just above a cylinder, to which the spindle is connected. Turning the knob pulls the cylinder in the direction of the turn.

The end of the cylinder is the latch, which protrudes into a space carved out of the door frame, and which prevents the door from opening if the knob is not turned.

A spring or similar mechanism makes the latch to return to its protruding state whenever the knob is not being turned. Escutcheon plates are typically 0placed around the knob and the place from that the latch protrudes.

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