Patent · US Expired

Typewriter spiral disc printer

US4149809A · kind A · utility

0Cited by
4References
2Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 27, 1978
Grant dateApr 17, 1979
Priority date
Expiry dateJan 27, 1998

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB41J1/30
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

A rotatable disc type printer for use in conjunction with a typewriter having a movable carrier. The type element or characters are carried on radially extending petals and are arranged at varying distances from the center of disc rotation so as to define a circumferential spiral path. The angular placement or position of each petal or spoke is determined by the following formula: angular placement of i.sup.th petal=360.degree./n .+-. tan .sup.-1 id/nL where n defines the total number of petals, d is the character spacing and L is the minimum distance from the center of disc to the print point. The length or distance from the center of disc rotation to the type character or element is defined by: L.sub.i (length for i.sup.th element=.sqroot.i L.sup.2 +(i/nd).sup.2 where i/nd ids the linear distance of travel of the disc center while rotating from a home position to the position for printing the character carried by the i.sup.th petal. In addition, the vertical center line of each type character is angularly displaced from the petal center line by an angle equal to tan .sup.-1 id/nL (i.sup.th element). In essence the disc rotates and linearly moves along a path parallel to the typew…

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