US 4,039,256 AGranted

Intermittent film transport registration stabilization device

AssigneeAmpex Corporation

InventorsLawrence R. Teeple, Jr., Andrew K. Magyary, Kenneth N. Severs

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Abstract

The invention provides a modification of the conventional rolling loop transport system, which enables the system to operate at the relatively high pull-down speeds required to match the 1.3 millisecond vertical blanking times of a video format, thereby allowing use of the improved transport in a video system. The instant transport utilizes two gaps in a rotor set apart at 180.degree., entrance of the film at a selected shallow angle, a shortened distance from the exposure gate to the film outlet with no decay of the film loop until expulsion, and a secondary pair of fixed registration pins disposed at the point of expulsion of the film at the film outlet which, in conjunction with a vacuum platen extending from the exposure gate to the film outlet, significantly reduces the jitter at the exposure gate, to allow the use of the transport in high density laser or electron beam recorders.

Claims10

Dependent claims

A film transport for intermittently moving a film past an exposure gate at relatively high pull-down rates commensurate with television systems, the transport including a stator, a rotatable rotor concentric within the stator to define a film passage therebetween, film supply/guide means for supplying and retrieving the film, and means for recording on the film via the exposure gate, comprising the combination of;

a single sprocket disposed to introduce the film from the film supply/guide means to the film passage between the stator and rotor at a selected shallow inlet angle;
said rotor including selected gaps formed in the circumference thereof for gradually forming therein film loops which reach their full size of an exposure frame length upon arriving at the exposure gate;
means for expelling the film loops in their full size condition shortly after their passing the exposure gate;
said means for expelling including expulsion pin means located at the expulsion point of the film loops for preventing back forces upon the film in the exposure gate in response to expulsion of the full size loops;
and
vacuum means cooperating with the means for expelling the film loops to stabilize the film in the exposure gate during the recording process.

3 more elements

Dependencies are inferred from the claim text.