Refractor having simplified cylinder lens assembly
US4606624A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 13, 1983 |
| Grant date | Aug 19, 1986 |
| Priority date | — |
| Expiry date | Oct 13, 2003 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B3/0285
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
Disclosed is a refractor of the type having a housing which has patient eye position for viewing along a sight axis extendible therethrough, a pair of superimposed cylinder lens assemblies, means for positioning a particular lens in front of the sight axis, axis control means for controlling the axis of each cylinder lens, a cross-cylinder assembly which is synchronously coupled with said cylinder lens assemblies. The improvement of such type of refractor comprises the positioning means including an internally threaded cylinder axis drive gear having a lock shaft, said gear located outside of the housing and having its lock shaft extending through an opening in the housing coincident with the common axis of both carriers, said shafted cylinder axis drive gear riding upon bearing means disposed between it and the housing. The housing opening for the lock shaft has a sleeve within the housing which circumscribes the opening. There is an annular space formed between the lock shaft and the sleeve. The sleeve retains a first bearing means followed by a first said carrier, the shaft of a shafted cell drive gear then fitting between the annular space formed between the sleeve and the lock…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.