Motion picture projection : an elementary text book (1928)

Record Details:

Something wrong or inaccurate about this page? Let us Know!

Thanks for helping us continually improve the quality of the Lantern search engine for all of our users! We have millions of scanned pages, so user reports are incredibly helpful for us to identify places where we can improve and update the metadata.

Please describe the issue below, and click "Submit" to send your comments to our team! If you'd prefer, you can also send us an email to mhdl@commarts.wisc.edu with your comments.




We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.

Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.

552 MOTION PICTURE PROJECTION Simplex star and cam with proper adjustment and perfect lubrication will stand for four or five years of constant use. Care in adjustment must be exercised, for the very best results can only be obtained when the star is so adjusted, when its "locking" or radius surface bears upon the cam flange just sufficiently to allow a thin film of oil to work between the two surfaces. Under no circumstances should the star be set up so tightly that there is even the slightest bind or "drag" apparent, for it must be borne in mind that the movement, working at operating speed develops certain friction between the two surfaces of the star and cam. Friction develops heat, and heat in turn develops expansion, which if too great will tend to tighten up the intermittent movement. To adjust: — loosen two screws, S-125-B, P.l (being careful not to let them unscrew so far that they will drop out), then apply the fork end of Simplex spanner wrench to hexagon nut on eccentric bushing, B-4, P. 4 and turn slightly either forward or back (very gently), until lost motion which is determined by rocking intermittent sprocket is quite taken up. Make sure when rocking or testing the sprocket that the star is in locking position, or in other words, that when turning the fly wheel the sprocket has entirely stopped turning and is in a position when the radius of the star is locked onto the flange of the cam wheel. Now tighten screws S-125-B, P.l which completes the operation, but if tightening of screws should bind the star against cam, loosen screws again and allow for binding space.