JPS5826748A - Detector for moving member in electrophotographic copying machine - Google Patents

Abstract

PURPOSE:To detect a copying paper appropriately, by a method wherein the copying paper is passed between a discharging member and a counter electrode to destaticize or electrify the paper by a discharge current, and the current flowing into the counter electrode is changed, in a detector for paper or the like moved in a copying machine. CONSTITUTION:The discharge current 10 discharged from the discharging current 3 flows through the counter electrode 4 and a load resistor, so that a voltage following up to the current 10 is induced at a detection point 6, and the volage is outputted as a detection signal at an output terminal 11 through a detecting part 7 and an amplifying part 8. On the other hand, when the paper 1 is advanced to a position faced to the discharging electrode 3 (in a static electricity removal step), the paper 1 is destaticized by the current discharged from the electrode 3, so that the current 10 flowing into the counter electrode 4 is changed in magnitude. As a result, the voltage at the detection point 6 is changed to change the detection signal outputted at the terminal 11, and accordingly, the entering of the paper 1 into the destaticizing step is detected by the change in the detection signal.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for detecting members such as sheets of paper moving within an electrophotographic copying machine.

In an electrophotographic copying machine, in order to detect paper jams and the like, it is necessary to detect whether all sheets have passed through a charging process, a static electricity removal process, etc.

For this purpose, a means for detecting the paper, such as a contact material such as a switch, is used in the charging process and neutralizing process.

A device that utilizes light, ultrasonic waves, a change in capacity, etc. is provided separately from a discharge member that performs charging and neutralizing functions.

For this reason, a large installation space is required and the copying machine becomes large, which is undesirable.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to provide a moving member detection device for an electrophotographic copying machine that has charging and neutralizing functions and is capable of detecting all moving members such as paper. be.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 shows the static elimination process, in which a sheet of paper 1 serving as a moving member is conveyed and moved in the direction of the arrow along a moving path 2, and at the same time, a discharge occurs at a predetermined position 16° on the moving path 2! A discharge member 3 serving as a pole and a member 4 to be discharged serving as an opposing member are arranged to face each other with the movement path 2 in between.

The member 4 to be discharged is grounded via a load resistor 5 serving as a resistor, and a detection section 7 and an amplification section 8 are connected to a detection point 6 between the member 4 to be discharged and the load resistor 5.

9 is a discharge member power supply path.

Therefore, the discharge current 10 discharged from the discharge member 3 flows through the member 4 to be discharged and the load resistor 5, so that the discharge current is detected at the detection point 6! A voltage that follows zero is generated, and the voltage is outputted as a detection signal (voltage) to the output terminal 11 via the detection section 7 and the amplification section 8.

On the other hand, when the paper 1 enters the position facing the discharge member 3 (that is, the static elimination step), the static electricity is eliminated by the current discharged by the discharge member 3, so that the discharged member 4 is For this reason, the voltage at the detection point 6 also changes and the ultra-fine signal output to the output terminal 11 changes, so it is possible to detect that the paper 1 has entered the static elimination process based on the change in this detection signal. .

FIG. 2 is an explanatory diagram of the charging process, in which the member to be discharged 4
The photoreceptor is grounded through a load resistor 51&:, and a detection section 7 and an amplification section 8 are connected to the detection point 6, and the operation is the same as described above.

The present invention is as described above, and the moving member 1 is completely neutralized.

Since the movable member 1 can be detected while being charged, and the installation space can be reduced, the copying machine can be made smaller and more compact.

[Brief explanation of the drawing]

Are Figures 1 and 2 different embodiments of the present invention? FIG. 1 is a moving member, 2 is a moving path, 3 is a discharge Wt pole, 4C is a counter electrode, and 5 is a resistor. Applicant Fuji Xerox Co., Ltd. Agent Patent Attorney Masaaki Yonehara Patent Attorney Tadashi Hamamoto

Claims (1)

[Claims] A discharge electrode 3 and its opposing electrodes 4 and 1 are provided across the moving path 2 of the moving member 1, and the opposing electrode 4't' is grounded via a resistor 5, and means for detecting the voltage of the resistor 5 is provided. A moving member detection device in an electrophotographic copying machine characterized by the provision of◎