Patent · US Expired

Retractable, refillable, sharpen-free pencil assembly

US5292202A · kind A · utility

7Cited by
5References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 5, 1993
Grant dateMar 8, 1994
Priority date
Expiry dateJan 5, 2013

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB43K21/003
  • WIPO fieldOther consumer goods
  • WIPO sectorOther fields

Abstract

A retractable, refillable, sharpen-free pencil assembly comprises an outer tube, an inner tube and several sections of pre-sharpened leads. The inner tube is movable relative to the outer tube. An upper half portion of the inner tube is enlarged by fitting a squeezing tube such that a spring can be positioned below the squeezing tube. When the inner tube is shifted, a lower portion of a spring pushes a lowest lead to a chucking device by which the lead is tightly gripped. A push plate attached to the slot of the outer tube has a squeezing portion engaged with the last coil of the spring. Sliding the push plate upward can pull the lower portion of the spring out of the inner tube. The propelled lead can be retracted into the inner tube and the inner tube can be pulled back and enclosed completely by the outer tube.

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