Patent · US Expired

Presentation device used in combination with an overhead projector

US4946274A · kind A · utility

8Cited by
2References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 25, 1989
Grant dateAug 7, 1990
Priority date
Expiry dateApr 25, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B21/132
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A presentation device for an overhead projector according to the present invention comprises a panel unit, which includes a liquid crystal panel, and a case for encasing the panel unit. At least one recess is formed in the outer surface of the panel unit which faces downward during use, and a movable leg is rockably mounted in the recess. During the use of the panel unit, the movable leg is caused to project from the recess by the urging force of a torsion coil spring. The case has an opening edge defining an inlet opening through which the panel unit is inserted into the case. The opening edge serves as an operating portion which is adapted to engage the movable leg, thereby rocking the leg against the urging force of the coil spring, so that the leg is housed in the recess, when the panel unit is inserted into the case through the inlet opening.

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