JPH03153280A - Initial setting device for transfer current value of electrophotographic copying machine - Google Patents

Abstract

PURPOSE:To perform initialization to the best transfer current value corresponding to a form in use and to simplify the operation by storing the best transfer current values by the kinds of forms and sending the best transfer current value based upon an input signal to a controller. CONSTITUTION:The controller 25 is equipped with an initial value setting circuit 26 and an arithmetic circuit 27 and one of the best transfer current values stored in an initial transfer current storage circuit 28 is inputted to the initial value setting circuit 26. Then the initial transfer current value storage circuit 28 is preliminarily stored with the best transfer current values corresponding to the kinds of forms and the respective best transfer current values are given addresses, which correspond to set mode codes by countries; when one set mode code is inputted, the best transfer current value matching the kind of form used in the corresponding country is set in the initial value setting circuit 26 of the controller 25. Consequently, the initial setting operation for the transfer current value corresponding to the kind of form of the country is facilitated when an electrophotographic copying machine is assembled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for initializing a transfer current value of an electrophotographic copying machine.

[Conventional technology]

In an electrophotographic copying machine, the surface of a sensitive material is uniformly charged with a charger, then imagewise exposed to form an electrostatic latent image, and this electrostatic latent image is developed into a toner image with a developing machine. It is known that a toner image is transferred onto paper using a transfer device, and the paper on which the toner image has been transferred is sent to a fixing device to be fixed, thereby making a copy.

The operation of transferring a toner image onto paper by a transfer device in such an electrophotographic copying machine is shown in FIG.

That is, a transfer device 4 consisting of a corona discharger with a discharge wire 3 stretched across a shield 2 is disposed facing the sensitive material 1, and by passing a high voltage current through the discharge wire 3, static electricity is generated on the surface of the sensitive material 1. This is so that the toner 5 attached by force is attached to the paper 6.

[Problem to be solved by the invention]

With such a transfer operation, assuming that the adhesion force of the toner 5 to the photosensitive material 1 due to electrostatic force is constant, the transfer efficiency of the toner 5 changes depending on the transfer current value to the discharge line 3, so that the transfer is most efficient. The optimum transfer current value that can be achieved is initially set at the time of assembly, but if the type of paper, for example the material, is different, the above-mentioned optimum transfer current value will be different, causing uneven solid density, and even if the material is the same, surface roughness may occur. If the image quality is different, the transfer efficiency will be constant, but the appearance of the copy may differ.

On the other hand, electrophotographic copying machines are often used in countries other than Japan, and the types of paper used in electrophotographic copying machines differ depending on the country.

For this reason, when assembling an electrophotographic copying machine, it is necessary to initially set the transfer current value according to the paper type of the country in which it is used, which is a very troublesome task.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a transfer current value initial setting device for an electrophotographic copying machine that can solve the above-mentioned problems.

[Means and effects for solving the problem] (1) The optimum transfer current value for each type of paper is stored, and the optimum transfer current value based on the input signal is sent to the controller, so that the optimum transfer current value corresponds to the paper used. It is possible to initialize the optimum transfer current value.

(2) The optimum transfer current value is sent to the controller using the country set mode code, and by inputting the country set mode code, the optimum transfer current value corresponding to the paper used in that country can be initialized. This is what I did.

〔Example〕

As shown in FIG. 2, a photosensitive material 1 provided inside the copying machine main body 10
A charging device 12, an image exposure section 13, a developing device 14, a transfer device 15, a peeling device 16, a cleaner 17, etc. are sequentially arranged around the image forming device 1.
0, and a platen 21 and an operation panel 22 are provided on the top of the copying machine main body 10 to constitute an electrophotographic copying machine.

As shown in FIG. 1, the transfer device 15 and the peeling device 16 have shields 15a and 16g and discharge wires 15b.

16b, and its discharge wire 15
A high voltage current is supplied to b and 16b from a high voltage circuit 23.24, and a control command is input from a controller 25 to the high voltage circuit 23.24 to set a predetermined current value.

The controller 25 includes an initial value setting circuit 26 and an arithmetic circuit 27, and one of the optimum transfer current values stored in the initial transfer current value storage circuit 28 is input to the initial value setting circuit 26.

The initial transfer current value storage circuit 28 stores in advance the optimum transfer current value corresponding to the paper type, and each optimum transfer current value is assigned an address, and the address corresponds to the country setting mode code. When the separate set mode code is input, the optimum transfer current value suitable for the paper type used in that country is set in the initial value setting circuit 26 of the controller 25.

The arithmetic circuit 27 receives the value of the current flowing through the shield from the ammeter 29 of the shield 15a, and outputs a control command to the high voltage circuit 23 so that the difference between the shield current and the optimum transfer current is constant.

In other words, the current value 1 dyn given to the paper 19 from the discharge wire 15b is the current value IT flowing through the discharge wire minus the shield current Is, and since the current value 1 dyn changes due to a change in the shield current Is, Current value I↑
is controlled to keep the current value I dyn constant.

The peeler 16 makes it easier for the paper 19 to peel from the photosensitive material 1 after transfer, and as the current value applied to the paper 19 from the transfer device 15 increases, the peelability deteriorates. High voltage circuit 24 based on control commands
The control command is controlled to control the current value to the discharge wire 16b of the peeler 16 so that the paper 19 can be peeled off more easily than the photosensitive material 1.

〔Effect of the invention〕

(1) The optimum transfer current value can be easily initialized based on the paper used.

(2) By entering the country set mode code,
Since the optimal transfer current value can be initially set based on the paper used in that country, the assembly process is simplified because all you need to do is input the country-specific set mode code.

[Brief explanation of the drawing]

FIG. 1 is a transfer current control circuit diagram showing an embodiment of the present invention, FIG. 2 is a schematic explanatory diagram of an electrophotographic copying machine, and FIG. 3 is an explanatory diagram of transfer operation. 10 is a sensitive material, 15 is a transfer device, 15a is a shield, 15b
25 is a controller, 26 is an initial value setting circuit, and 28 is an initial transfer current value storage circuit. Applicant: Fuji Xerox Co., Ltd.

Claims (3)

[Claims] (1) In an electrophotographic copying machine that transfers the toner image formed on the sensitive material 11 onto the paper 19 using the transfer device 15, the optimum transfer current value for each paper type is memorized and the optimum transfer is performed based on the input signal. A transfer current value initial setting device for an electrophotographic copying machine configured to send a current value to a controller 25 that controls current to a transfer device 15. (2) The transfer current value initial setting device for an electrophotographic copying machine according to claim 1, wherein the optimum transfer current value for each type of paper can be sent to the controller 25 using a country-specific set mode code. (3) The present invention comprises an initial transfer current value storage circuit 28 that stores the optimum transfer current value for each paper type, and a controller 25 that controls the transfer current based on the optimum transfer current value set in the initial value setting circuit 26. A transfer current value initial setting device for an electrophotographic copying machine according to items 1 and 2.