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1947-48 Theatre Catalog, 6th Edition, Page 338 (324)

1947-48 Theatre Catalog, 6th Edition
1947-48 Theatre Catalog
1947-48 Theatre Catalog, 6th Edition, Page 338
Page 338

1947-48 Theatre Catalog, 6th Edition, Page 338

DeVry's 12000 Series Projection Equipment

Projector Mechanisms, Bases, and Changeovers

Redesigned for Large and Drive-in Theatres

The DeVry 12000 Series of 35-mm. motion picture projection equipment (Figure 1) includes a new design of projector head, new designs of projector bases, amplifiers in various powers up to 250 watts, and speakers designed to accommodate theatres of maximum size to the drive-in theatre speaker usable within a car.


The projector mechanism head incorporates the sound head components usually supplied in a separate unit.

This basic construction allows for great economy and maximum simplification of the mechanical drive for all of the projector functions. The projector


DeVry Corporation

head itself is aligned and secured to a mounting plate in such a manner as to permit rapid head replacement in correct projection alignment in case of need, and the switchover from defective head to replacement head can be occomplished very rapidly.

Securement of Parts

The basic components utilized in the mechanism construction are protected against corrosion or rust by suitable platings or the use of corrosion resistant material. Assembly of parts to the main

FIGURE 1*The 12000 Series of 35-mm. motiompicture projection equipment of. the DeVry Corporation includes a new design projector head and new designs 0! projector bases, as well as amplifiers in various powers up to 250 watts, and speakers designed to accommodate theatres of maximum size to the drive-in theatre speaker. The proiector head incorporates the components at the sound head.

mechanism plate is with through bolting where possible or mechanical locking devices of various approved types.

Basic Construction

The 12000 projector head is built around a main center mounting plate of normalized aluminum of adequate crosssection to guarantee permanent correct alignment of the optics, sprockets, intermittent mechanism, sound head, and so forth.

All of the power driving mechanism is mounted on the non-operating side of the mechanism main frame and is accessible for service or inspection by a latched, hinged door. Conversely, all of the film handling equipment is mounted on the operating side of the mechanism plate and it, too, is accessibly by a latched, hinged door in which a the resistant glass port is installed for inspection of the proper operating loops during projection.

Intermittent Movement

The intermittent movement (Figure 2) is of the 90-degree Genevascross type, the cam and star operating in an oil chame her. The entire intermittent movement is readily replaceable and is doweled to the framing mechanism so that proper timing may be maintained when removed for inspection, repair or replacement. Lubrication of shaft bearings is by oil canals ground on the shaft, oil feeding from the reservoir. Final end performance of the intermittent is such as to result in a projected picture jump of less than 0.25 percent at a 100 foot projection distance.


One hundred percent synchronous framing is accomplished in an ingenious manner, utilizing the chain drive feature (Figure 3) so as to maintain perfect synchronization between the star and cam crossover point and the shutter position. This is accomplished by rotation of the intermittent housing and sprocket around the intermittent sprocket axis through sufiicient angle to allow framing over two picture frames.

Synchronization with the shutter is accomplished by synchronizing the rotary movement of the intermittent housing with two vertical moving chain idlers so as to maintain the same eHective distance with respect to chain length between the crossover point of the star and cam and the correct shutter position for 100 percent synchronizatirm.

Film Rails

Film rails (Figure 4) on which the film rides at the aperture are made of hardened ground stock that is then chrome plated to reduce frictional resistance, thus allowing the maintenance of adequate tension on the film during

1947-48 Theatre Catalog, 6th Edition, Page 338