Patent · US Expired

Device for determining the forces in the area of the contact surfaces between a spectacle frame and the head of the wearer

US4873994A · kind A · utility

6Cited by
13References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 26, 1989
Grant dateOct 17, 1989
Priority date
Expiry dateJan 26, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01L5/00
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Described is a device for testing for a perfect fit of spectacle frames on the head of the spectacle wearer. The device has at least one plate- or blade-shaped force or pressure sensor, which is mounted on a holder and can be applied to the respective contact surfaces between the frame and head. With this device it is possible to make precise measurements of the forces and pressures actually occurring at each individual point so that they can be reproduced, for example, by raising the frame slightly, introducing the pressure sensor to the pertinent point of contact, and lowering the frame down again. Becausede of the negligible structural height of the pressure sensor, the individual contact areas between the frame and head can be tested without having to make any change in the controlled vane position in space existing when the spectacles are worn in place.

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