Patents Assigned to T & T Mfg. Co.
  • Patent number: 4354767
    Abstract: A mechanical pencil has a clutch feature which prevents the breakage of the lead-carrying mechanism when the mechanism is advanced or retracted too hard or encounters an obstruction anywhere during its travel along the guide tube. The stationary lower barrel and guide tube are rotatably fixed to a rotating upper cap, knurled bushing and worm spring which drive the lead carrier along the stationary guide tube to advance and retract the lead. The lower end of the worm spring and the upper end of the cap bushing are linked together by clutch means which permits their relative slippage when excessive torque forces are encountered.
    Type: Grant
    Filed: June 20, 1980
    Date of Patent: October 19, 1982
    Assignee: T & T Mfg. Co.
    Inventor: Aram J. Tessier