Patent · US Expired

Rotary knock type mechanical pencil

US5022772A · kind A · utility

9Cited by
7References
7Claims
0Family size

Assignees

Inventors

Key dates

Filing dateSep 11, 1989
Grant dateJun 11, 1991
Priority date
Expiry dateSep 11, 2009

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB43K24/06
  • WIPO fieldOther consumer goods
  • WIPO sectorOther fields

Abstract

A rotary knock type mechanical pencil in which the forward and rearward outer cylindrical are relatively rotated, a cam movement converting mechanism stored in the forward outer cylinder converts the rotary movement into an axial advancing or retracting movement, the lead feeding mechanism may feed the lead of desired length from the extremity end of the mechanical pencil under a knocking operation in the shaft comprising: a cam cylinder integrally rotating with the rearward outer cylinder; that includes two cam surfaces and an engaging part which allows retraction of a lead guide pipe a rotary cam mechanism for converting the rotary movement of the cam cylinder into a reciprocating advancing or retracting movement while slidably contacting with the cam surface formed at the extremity end surface of the cam cylinder; a lead feeding mechanism including an advancing or retracting mechanism such as a cassette adapter for advancing or retracting the lead chuck attached to the extremity end under a reciprocating movement applied through the rotary cam mechanism, a lead chuck for holding the lead, and a tightening member freely inserted into the extremity end of the load chuck and for ho…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.