Roll film drive control arrangement
AssigneeMinolta Camera Kabushiki Kaisha
InventorKeiji Nakatani
Life of this patent
Estimating the term…
Abstract
Drive control arrangement for roll film having an end attached to a reel shaft and in which an increase in the load imposed on a reel drive motor caused by increased tension in the film when the attached end of the film is reached during film unwinding, or rewinding, is detected by a detection means which in response to the load increase produces an output causing the motor power supply circuit to open, whereby movement of the film is stopped, and risk of damage to the film or the drive system is avoided. The invention offers the advantage that no special marking of the film is required, and that the drive means is easily associated with conventional film drive systems.
Claims10
A drive control arrangement for use in a drive means for roll wound tape-like material having at least one end thereof fixed to a rotary shaft, said drive control arrangement comprising;
- means for detecting variations of electric current flowing through the armature of a motor of said drive means, and
- switching means to be actuated in response to output of said detecting means for controlling selective energization and de-energization of said motor,
- said detecting means emitting a signal upon detection of an increase of the electric current flowing through the armature of said motor caused by the increased tension in the tape-like material when said fixed end of the tape-like material has been reached during driving of the tape-like material, said switching means causing said motor to be de-energized upon receipt of the signal from said detecting means for interrupting driving of the tape-like material.
A drive control arrangement for use in a drive means for a roll film having at least one end thereof fixed to a rotary shaft, said drive control arrangement comprising;
- means for detecting variations of electric current flowing through the armature of a motor of said drive means,
- switching means to be actuated in response to output of said detecting means for de-energizing said motor, and
- resetting means actuable to terminate the output of said detecting means and to cause said motor to rotate in a reverse direction,
- said detecting means emitting a signal upon detecting an increase of the electric current flowing through the armature of said motor caused by increased tension in the roll film when said fixed end of the roll film has been reached during driving of the roll film, said switching means causing said motor to be de-energized upon receipt of the signal from said detecting means for interrupting driving of the roll film, and said output of said detecting means being terminated through actuation of said resetting means, with said motor being simultaneously caused to rotate in the reverse direction for rewinding the roll film.
Dependencies are inferred from the claim text.