JPS54111834A - Density control device of copying machine - Google Patents

Abstract

PURPOSE:To perform density controlling and enable density to be set arbitrarily by setting the density with the keyboard on the outside of the copying machine body and controling the number of revolutions of a feed roller. CONSTITUTION:When a desired density suited to the original is inputted from ten keys 10, an encoder 15 converts this to a binary code. A selection circuit 21 supplies this to a memory device 31 to have the input data stored. The stored data is displayed in a display device 32 and at the same time it is converted by a first decoder 33 to a decimal signal to drive a first driving device 40. This turns ON a solenoid 38 to revolve a feed roller. As the feed roller revolves, the signal from a cam switch SW 41 is counted with a counter 45, whose output is then supplied to a second decoder 46 to be converted to a decimal signal. This signal is supplied to a comparator 36 where it is compared with the input data from the ten keys 10. When the feed rollers revolves as much as the number of revolutions conforming to the input data and the desired toner instructed from the ten keys 10 is supplemented, the input signal of the comparator 36 coincides and the solenoid 38 goes OFF. The feed roller then stops.