Photocopying – Projection printing and copying cameras – Focus or magnification control
Patent
1988-06-21
1989-09-19
Wintercorn, Richard A.
Photocopying
Projection printing and copying cameras
Focus or magnification control
G03B 2736, G03B 2738
Patent
active
048686034
ABSTRACT:
A variable magnification optical system for a copier has a movable lens (10) of fixed focal length for projecting an image of an original document with a desired magnification within a predetermined range, e.g. 0.64 to 1.54, onto a photoreceptor (6). The lens 10 is fixed on a carriage (12) which is slidable along an elongate cam member (13) inclined to the optical axis. The lens is coupled to a cam foller (11) which is slidably mounted on the carriage 12. Cam member (13) has an arcuate camming surface (20) against which the cam follower (11) is urged so that the lens (10) describes an arcuate path as the carriage (12) travels along the cam member (13) enabling the top edge of the original document to be registered with a datum of the photoreceptor (6) for all magnifications. The camming surface (20) is extended beyond that necessary to achieve the predetermined magnification range for the lens, and the cam member (13) is movable relative to the cam follower (11) to alter the portion of the camming surface with which the cam follower cooperates. This makes it possible to compensate on an individual basis for manufacturing tolerances in the focal length of a particular lens used and thereby maintain top edge alignment. In an example of a two dimensional cam the cam surface is extended at both its ends, and the cam member is movable longitudinally (see FIG. 2). In an example of a three dimensional cam the camming surface comprises a plurality of different arcs of the same curve disposed sequentially in adjoining relationship transversely to the plane of the curve, and the cam member is movable at right angles to the longitudinal axis.
REFERENCES:
patent: 4032231 (1977-06-01), Zucker
patent: 4077715 (1978-03-01), Greene
patent: 4093374 (1978-06-01), Zucker et al.
patent: 4530592 (1985-07-01), Green et al.
patent: 4557594 (1985-12-01), Negoro
patent: 4641957 (1987-02-01), Tokeda
patent: 4657380 (1985-11-01), Hamano
Wintercorn Richard A.
Xerox Corporation
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