SU484481A1 - Device for controlling two film projectors - Google Patents

Description

Devices are known for controlling two film projectors, preferably with incandescent lamps, with continuous demonstration of films containing its motor powering unit of the projector and the station from post to post. The proposed device differs from the known one in that the post-to-fast transition unit is made of two magnetic starters, each of which has a power switch of the electric drive of one film projector and normally closed buttons for turning on the magnetic starter of the other film projector in series. This difference allows to simplify the design of the device and facilitate the management of two film projectors. The drawing shows a schematic diagram of the described device. In the film projector 1, a toggle switch 2, having a neutral position, is connected by middle contacts 3 to pin 4 of the electric motor 5 of the tape drive and to the coil of the magnetic actuator 6. Another middle pin 7 of the toggle switch 2 is connected to the output of the electric motor 8 of the receiving cassette. The contacts 9, 10 and 11 of the toggle switch 2 are activated by a voltage to supply the 5 n 8 electric motors and the coil of the magnetic actuator 6 on one side. The voltage applied to the 5 n 8 electric motors on the other hand is made directly from the power source. The second output of the coil of the magnetic actuator 6 is connected to the normally open contact 12 of the button 13 of the junction node from the station to one of the terminals of the block contact 14 of the starter 6. Another terminal of the block contact 14 through the jumper 15 and the switching hose is connected to the normally closed contacts of the button 16 transition nodes from a post to a post located on another film projector. Normally: the open contacts 17 of the actuator 6 are connected in series to the power supply circuit of the sound-reading lamp 18. Normally open contacts 19 of the actuator 6 are connected in series to the power supply circuit of the projection lamp 20. Normally closed contacts 21 of the actuator 6 are connected in series to the power supply circuit of the backlight lamp 22. "The second projector contains exactly such controls connected in the same way. The operation of the device during continuous demonstration of movies is as follows. If the beginning of the session is made from the film projector 1, then the cinema mechanic starts up the toggle switch 2 in the upper position and starts the electric motor 5 of the tape path and the electric motor 8 of the receiving cassette. With

This prepares the coil circuit of the magnetic actuator 6 for operation. As soon as the initial tape breaker passes through the tape path of the film projector 1, the cinema mechanic presses button 13. The magnetic starter 6 operates. Block contact 14 locks the start contacts of button 13, and the coil is powered through the normally closed contacts of button 16 of the projector 23. Contacts 17 include the sound is: its lamp 18, contacts 19 turn on the projection lamp 20, and contacts 21 turn off the backlight 22. The film has begun to project onto the screen.

A film projector 23 is prepared for the demonstration of the next part of the film.

At the first signal point at the end of the demonstration part of the film, the projectionist turning on the toggle switch 24 to the upper position starts the motor 25 of the tape path of the film projector 23 and the motor 26 of the receiving cassette.

In this case, the power supply circuit of the magnetic actuator 27 is prepared for operation. At the second signal point, the projectionist presses the button 16. The magnetic starter 27 triggers. 29 turn on the sound-reading lamp 30, contacts 31 turn on the projection lamp 32, and contacts 33 turn off the backlight lamp 34. At the same time, the power supply circuit of the coil of the magnetic actuator 6 is broken. Magnetic starter 6 comes in the initial state. Pins 17 and 18, open, turn on the lamps 18 and 20, and pins 21, close, turn on the backlight 22.

As soon as the projection of the next part of the film from the film projector 23 begins, the cinema mechanic proceeds to the film projector 1 and after the completion of the tape section of the part with the toggle switch 2 turns off the electric motors 5 and 8. Then it starts charging the next part to the tape path.

During movie charging, one of film projectors 1 or 23 can be switched by switching the toggle switch 2 or 24 to the lower position from the electric motor 8 or 26 of the receiving cassette, i.e., the film can be rewound during charging to the tape path, and rewind the film directly on one of the film projectors without switching on the electric motor of the tape path. However, the operation mode of the other film projector is not disturbed.

Due to the fact that the coils of the magnetic starters 6 and 27 are connected to the same middle contacts 3 and 34 of the toggle switches 2 and 24, respectively, as the electric motors 5 and 25 of the tape path, it is impossible to turn on the projection lamps when the electric motors 5 and 25 are not turned on. This eliminates the ignition of the film in the film channel in case of violation of the sequence of the start of the film project.

Subject invention

A device for controlling two film projectors, preferably with incandescent lamps, with continuous demonstration of movies, comprising a switch-on unit for the film's electric drives and a station from post to post, characterized in that, in order to simplify the design and facilitate control, the station from post to post is made of two magnetic starters, the power supply coil of the electric drive of one film projector and the normally closed contacts of the power button agnitnogo actuator of another film projector.

P

18

N-oj

11 ± 1

13

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