SU484483A1 - Moving Film Speed Stabilizer - Google Patents

Description

one

The invention relates to film technology.

Known stabilizers for the speed of motion of a film, mainly for film projectors, containing a smooth drum with a flywheel, a rocker arm with guide rollers.

A distinctive feature of the proposed stabilizer is that the rocker is made in the form of a spring, for example, a flat, fixed central part on an axis that can be rotated in a fixed sleeve, and the spring is curved with a convex side to the smooth drum, which simplifies the design and maintains the same angle of coverage film roll smooth drum.

FIG. 1 schematically shows the proposed stabilizer; in fig. 2 is a section along A-A in FIG. one.

The stabilizing rolls 1 and 2 of the stabilizer are loosely mounted on axles 3, which are fixed to the crown 4, connected by a flat spring 5. The latter is fixed on axis 6, which can be rotated in sleeve 7 fixedly mounted on the casing 8 of the projector. At the end of axis 6, the groove grooves are cut, which are filled with silicone grease. These grooves serve as lubrication tanks, which, due to the high viscosity, acts as a damper.

The film 9 passes a tape mechanism, for example Maltese (not shown on the drawings), then enters the driven toothed drum 10, which is planted on the shaft frictionally. Next, the film 9 envelops the guide roller 1, the smooth drum 11 with the flywheel 12, the guide roller 2 and the guide roller 13 of the path mounted in front of the driving gear drum, which is rotated from the drive mechanism (not shown in the drawings).

The film speed stabilizer operates as follows.

With the passage of the film on the driven toothed drum 10 and the driving toothed drum there are variable effects on it. These variable influences (disturbances) are transmitted to the guide rollers 1 and 2 connected by a flat spring 5. At the same time, the circular frequency of natural oscillations of the flat spring 5 with the guide rollers 1 and 2 due to the small inertia of the system is greater than the circular frequency of disturbance that occurs when the perforations of the film are engaged. with the teeth of the driven and driving drums and causing 11 high-frequency detonations on a smooth drum. As a result, the flat spring with the guide rollers 1 and 2 appears in

state to follow the change in the film core, i.e. filter its oscillations with a frequency that exceeds the circular frequency of natural oscillations.

Low-frequency speed fluctuations, mainly due to the irrelevant effects of the shaft supports of the smooth drum and flywheel (usually ball pins), are extinguished by the flywheel of the smooth drum 12. The film is tensioned with a flat spring 5, as well as with the driven toothed drum 10.

To dampen the natural oscillations of the flat spring 5 with the guide rollers 1 and 2, a damper is used, which is the end of the axis 6 with longitudinal grooves filled with silicone grease.

Subject invention

Claims (2)

1. A film speed stabilizer, mainly for film projectors, comprising a smooth drum with a flywheel, a rocker arm with guide rollers and a damper, characterized in that, in order to simplify the design, the rocker arm is made in the form of a spring, for example a flat, fixed central part on the axis, installed with the possibility of rotation in a fixed sleeve. 2. The stabilizer according to claim 1, wherein in order to maintain the angle of coverage of the film of a smooth drum, the spring is curved with a convex side to the smooth drum.