Patent · US Expired

Reversible colorful writing apparatus

US6733298B2 · kind B2 · utility

4Cited by
11References
10Claims
0Family size

Inventor

Key dates

Filing dateJan 30, 2003
Grant dateMay 11, 2004
Priority date
Expiry dateMay 19, 2023

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB43L1/008
  • WIPO fieldOther consumer goods
  • WIPO sectorOther fields

Abstract

A reversible colorful writing apparatus includes a reversible writing board composed of a plurality of coloring picture tubes each filled with a plurality of immiscible coloring liquids in each coloring picture tube and suspended with a miniature magnet within each picture tube, and an inkless writing pen having a stepping-motor control circuit provided within the writing pen; whereby upon moving of the pen on the board, the stepping-motor control circuit will drive the miniature magnet forwardly (or reversely) in each picture tube to drive the immiscible coloring liquids forwardly (or reversely); and upon setting of the magnet at a specific position in the tube, a specific coloring liquid corresponding to such a specific magnet position will be driven to the top surface of the picture tube to display such a specific color on the board.

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