JP2943297B2 - Electrophotographic image forming equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus for forming an image by cutting a roll-shaped image output sheet into one image and supporting the image on a rotating drum.

[Prior Art] Conventionally, a photosensitive paper transport control device in an electrophotographic image forming apparatus has a configuration shown in FIG. That is, the photosensitive paper 1 stored in a roll shape is set in the cartridge 2, and the leading end thereof is supported by being sandwiched between the paper feed rollers 3a and 3b. The transport path is formed by a guide 4, and a paper position detection sensor 5, a cutter 6, and paper feed rollers 7a and 7b are arranged on the transport path in this order from the paper cartridge side. The transport path reaches a tangent near the drum 8. Inside the drum 8, suction holes 9 and 10 are provided at the leading suction position and the end suction position of the photosensitive paper, respectively. The suction holes 9 and 10 are connected to a suction pump 12 through a suction pipe 11. I have.

Fourth is a block diagram of the drive circuit. Center CPU21
The signal from the paper position detection sensor 5 is input to the paper transport CPU 22 connected to the CPU. Also, the paper transport CP
Based on a command from U22, a motor drive circuit 23 controls a motor 24 connected to the paper feed rollers 3a and 3b, and a motor drive circuit 25 controls a motor 26 connected to the paper feed rollers 7a and 7b.
Are connected so that they can be driven.

Next, the operation of the conventional example will be described. A new roll of photosensitive paper 1 is set in the cartridge 2 and the copy switch is operated. As a result, when an image forming command is output from the center CPU 21, the paper feed rollers 3a, 3b, 7a, and 7b all rotate the photosensitive paper 1 at a speed equal to the peripheral speed V (m / s) when the drum 8 rotates at a constant speed. The transfer CPU 22 is connected to the motor drive circuit 2
The command is transmitted to 3, 25, and the motors 24, 26 rotate at the same speed. When the leading end of the photosensitive paper 1 reaches the paper position detection sensor 5, a detection signal is output from the sensor 5 to the transport CPU 22, and the CPU 22 stops the motors 24 and 26.

When the leading position suction hole 9 reaches a predetermined position, the paper feed rollers 3a, 3b, 7a, and 7b are again rotated at a speed equal to the peripheral speed V (m / s) when the drum 8 is rotated at a constant speed. The paper 1 is transported. The photosensitive paper 1 is positioned so that the leading position matches the position of the suction hole 9 and wound around the drum 8. The cutter 6 cuts the photosensitive paper 1 so that the photosensitive paper 1 has a predetermined length. The rear end of the cut photosensitive paper 1 is a paper feed roller 7a,
After passing through the position 7b, a stop command is output from the transfer CPU 22, and the paper feed rollers 3a, 3b, 7a, 7b stop. Thus, the roll-shaped photosensitive paper 1 was wound around the drum 8.

[Problems to be Solved by the Invention] However, when replacing the roll-shaped image output paper,
When the outermost periphery of the roll-shaped image output paper is exposed to light or touched by an operator, the characteristics of the photoconductor may change or the surface may become dirty. Even in such a case, there is a problem that an image is formed on the outermost periphery of the roll-shaped image output sheet.

The present invention has been made in order to solve the above-described problems, and an electrophotographic method capable of always forming a good image even if the outermost peripheral characteristics of a roll-shaped image output sheet changes or the surface becomes dirty. It is an object to provide an image forming apparatus.

Means for Solving the Problems In order to achieve this object, an electrophotographic image forming apparatus of the present invention forms an image by cutting a roll-shaped image output sheet into one image and supporting it on a rotating drum. In the electrophotographic image forming apparatus, when the roll-shaped image output paper is replaced, a roll replacement detecting unit is provided, and when the roll-shaped image output paper is replaced, the image output paper for the outermost circumference is cut. And a paper transport control means for discharging the paper.

[Operation] In the electrophotographic image forming apparatus of the present invention having the above-described configuration, the roll replacement detecting means detects when the rolled image output sheet used so far is replaced with another rolled image output sheet. Is detected.

When detecting that the roll-shaped image output paper has been replaced based on the information transmitted from the roll replacement detection means, the paper transport control means transports, cuts, and discharges the image output paper having a length equal to or longer than the outermost circumference. .

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a configuration diagram of the present embodiment, and the basic configuration is the same as that of the conventional example, so that the description is omitted. The remaining paper amount detection roller 101 is supported by a support rod 102 and is connected to a resolver 103. The paper remaining amount detection roller 101 is lightly pressed against the photosensitive paper 1 by a spring. The resolver 103 is a support rod 102
Is read, and the angle information is transmitted to the paper transport CPU 22 as shown in FIG. The paper transport CPU 22 is the resolver 10
Based on the angle information from 3, it is recognized that the roll-shaped photosensitive paper 1 has been replaced when the remaining amount of the roll-shaped photosensitive paper 1 has rapidly increased.

That is, in the present embodiment, the paper remaining amount detecting roller 10
1. The support bar 102 and the resolver 103 constitute a roll replacement detecting means, and the paper transport CPU 22 constitutes a paper transport control means.

 Next, the operation of this embodiment will be described.

When recognizing that the roll-shaped photosensitive paper 1 has been replaced by a signal from the resolver 103, the paper transport CPU 22 issues a command to the motor drive circuits 23 and 25, and the paper feed rollers 3a, 3b, 7a,
7b is rotated to convey the rolled photosensitive paper 1 by a predetermined length. When the roll-shaped photosensitive paper 1 has passed the position of the cutter 6 by a predetermined length, the cutter 6 cuts the roll-shaped photosensitive paper 1. When the rolled photosensitive paper 1 is cut, the paper transport CPU 2
In 2, the paper feed rollers 3 a and 3 b are stopped, and the paper feed rollers 7 a and 7 b continue to rotate, and discharge the cut roll-shaped photosensitive paper 1 out of the apparatus.

When the cut rolled photosensitive paper 1 is discharged, the paper transport CP
U22 enters a standby state and outputs the signal to center CPU 21. Thereafter, when the copy SW is operated, the rolled photosensitive paper 1 is wound around the drum 8 in the same manner as in the conventional example, and an image is formed.

In the present invention, it is recognized that the roll-shaped photosensitive paper 1 has been replaced by a change in the remaining amount of the roll-shaped photosensitive paper 1,
Although this is used as the roll change detecting means, it is also possible to detect that the cartridge 2 has been removed from the apparatus and use this as the roll change detecting means. When information on the roll-shaped photosensitive paper 1 is recorded in a part of the roll-shaped photosensitive paper 1, the information is read, stored, and compared to determine that the roll-shaped photosensitive paper 1 has been replaced. The present invention can also be implemented by detecting the change and using this as a roll change detection unit.

[Effects of the Invention] As is clear from the above description, according to the present invention, a good image is always formed even if the outermost peripheral characteristics of the roll-shaped image output paper change or the surface becomes dirty. An electrophotographic image forming apparatus that can be used is provided.

[Brief description of the drawings]

1 and 2 show an embodiment embodying the present invention, and FIG. 1 is a configuration diagram of an electrophotographic image forming apparatus.
FIG. 2 is a block diagram of the same. 3 and 4 show a conventional example, FIG. 3 is a block diagram showing a conventional example, and FIG. 4 is a block diagram of the same. In FIG. 1, reference numeral 1 denotes a roll of photosensitive paper, 8 denotes a rotating drum, 22 denotes a paper transport CPU, and 103 denotes a resolver.

Claims (1)

(57) [Claims] An electrophotographic image forming apparatus which cuts a roll-shaped image output sheet into one image and forms the image by supporting the image on a rotating drum, a roll for detecting that the roll-shaped image output sheet has been replaced. An electrophotographic image forming apparatus comprising: a replacement detection unit; and a paper conveyance control unit that cuts and discharges the outermost circumference of the image output sheet when the rolled image output sheet is replaced.