JP2664307B2 - Suction device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is directed to suctioning ozone generated from a corona discharger (transfer device or the like) for performing corona discharge, and to prevent the paper from being lifted when the paper after toner transfer is transported. The present invention relates to a suction device that sucks a sheet.

[0002]

2. Description of the Related Art In a copying machine, a toner on a photoreceptor is transferred onto a sheet using a transfer device.

[0003] The paper on which the toner has been transferred is conveyed to the fixing unit on the suction belt. As the transfer device, a transfer device which generally performs corona discharge and electrostatically transfers toner on a photoreceptor to paper is used. Since the corona discharge generates ozone, the copying machine is provided with a suction device for sucking ozone.

Further, the suction belt transports the paper while the powder toner is loaded thereon, so that the suction belt transports the paper in order to prevent wrinkling, vibration, and the like of the paper. That is, a suction duct having a suction port is provided in the suction belt, and the suction belt is rotated by rotating the transfer belt while sucking the sheet, whereby the sheet is adsorbed on the transfer belt and transferred. doing. Generally, in terms of cost and space,
The negative pressure for ozone suction and the negative pressure for transporting the paper are generated by one negative pressure generator (usually a fan is used). The duct connected to the fan was composed of a paper suction unit that continued to the suction belt side, and an ozone suction unit that diverged from the paper suction unit side and continued to the transfer unit side.

[0005]

By the way, when the paper size is large, when the paper is on the suction belt, its end is located at least on one of the photoconductor and the fixing unit, Since the sheet conveyance is assisted by the fixing unit, the sheet can be sufficiently conveyed even if the sheet suction force (negative pressure) by the suction belt is not so large.

However, when the sheet size is small, the sheet is conveyed only by the suction belt, so that a large sheet suction force (negative pressure) is required. For this reason, it is conceivable to provide a negative pressure generator (fan) capable of generating a negative pressure that satisfies a suction force for conveying a small-sized sheet + a suction force for ozone suction. Must have a fan with great ability,
There are problems of high cost and space.

Therefore, conventionally, an on-off valve is provided at a branch position between the sheet suction unit and the ozone suction unit, and the on-off valve is opened and closed by a special valve opening and closing mechanism such as a solenoid or a link mechanism, so that ozone is sucked during sheet conveyance. The suction force on the side was cut off to prevent the fan from becoming larger. However, such a suction device requires a special valve opening / closing mechanism, which hinders simplicity of the configuration and miniaturization, and also has a problem of long-term reliability of operation due to an increase in the number of mechanical components.

SUMMARY OF THE INVENTION An object of the present invention is to provide a suction device that directly operates an on-off valve simultaneously with sheet detection with a very simple mechanism.

[0009]

According to the present invention, there is provided a duct connected to a negative pressure generator such as a fan, and the duct is piped to a suction belt position for conveying a sheet to constitute a sheet suction section. The duct is branched and piped at a corona discharger position to form an ozone suction unit. Further, an actuator that is pressed when the paper passes over the suction belt, and a rotation that rotates when the actuator is pressed A shaft, a detection unit that detects a sheet by the operation of the actuator, and an on-off valve provided on the rotation shaft and disposed at the branch position. The on-off valve at the branch position is provided by rotation of the actuator. Work, and
It is characterized in that paper detection is performed.

[0010]

According to the present invention, the opening / closing valve provided at the branch position is rotated by the rotation operation of the actuator to directly open and close the branch position. When the on-off valve is in the open state, the negative pressure generated by the negative pressure generator is supplied to both the paper suction unit and the ozone suction unit, and can perform both paper suction and ozone suction. Further, when the on-off valve is in the closed state, the supply of the negative pressure to the ozone suction unit side is not performed, and all the negative pressure generated by the negative pressure generator is supplied to the paper suction unit and the paper is suctioned. .

When the sheet passes over the suction belt, the actuator is pressed by the passing sheet and rotates to be closed when the sheet passes over the suction belt. Therefore, when the sheet passes over the suction belt, a negative pressure is generated. Most of the negative pressure generated in the container is sent to the paper suction unit side. The detection unit detects the passage of the sheet by the rotation operation of the actuator, whereby another processing operation such as a jam detection is performed.

[0012]

FIG. 1 is a diagram showing a main configuration of a copying machine according to an embodiment of the present invention.

Around the photosensitive drum 1, a charging charger 11, a blank lamp 12, a developing tank 13, a registration roller 14, a transfer / peeling charger 15, a remover tape 1
6, peeling nail 17, cleaning device 18, static elimination lamp 1
9 are arranged in the above order. The photoreceptor drum 1 is charged by a charging charger 11 and is exposed by reflected light of a document set on a document table (not shown) to form an electrostatic latent image. The area outside the image area is exposed by the blank lamp 12 to be neutralized. The developing tank 13 visualizes the electrostatic latent image by attaching toner to the electrostatic latent image. A sheet on which a copy image is to be formed is fed by a registration roller 14, and a toner image is transferred to the sheet by a transfer charger section of a transfer / separation charger 15. Thereafter, the sheet is peeled from the photosensitive drum 1 by the remover tape 16, the peeling charger portion of the transfer / peeling charger 15, and the peeling claw 17. The cleaning device 18 collects the toner remaining on the photosensitive drum 1, and the charge removing lamp 19 removes the charge remaining on the photosensitive member.

A suction belt 2 is disposed downstream of the transfer / separation charger 15 (in the paper transport direction), and a fixing device 3 is further downstream thereof. The sheet peeled off from the photosensitive drum 1 by the remover tape 16 and the peeling claw 17 is conveyed to the fixing device 3 by the suction belt 2 and is fixed by the fixing device 3.

A suction device is disposed at 15 parts of the transfer / peeling charger and 2 parts of the suction belt. FIG. 2 is a diagram showing the appearance of the suction device. The suction device includes an ozone suction unit 4, a paper suction unit 5, an axial fan 6, and an on-off valve driving unit 7.

The ozone suction unit 4 includes the transfer / peeling charger 1
5, a plurality of intake holes 4b are formed on the surface side of the duct portion 4a formed in a rectangular parallelepiped shape. When the axial fan 6 operates to generate a negative pressure,
Ozone generated around the transfer / peeling charger 15 is sucked through the hole 4b. The ozone suction unit 4
An ozone filter (not shown) is disposed in the inside, and adsorbs ozone.

The paper suction unit 5 has a plurality of holes 5b formed on the surface of a duct 5a having a rectangular parallelepiped shape. The belt 2a of the suction belt 2 is provided around the duct 5a.
Is provided. The suction belt 2 has a transport belt 2a stretched between rotatable rollers 2b and 2c. The transport belt 2a is formed in a plurality of belt shapes, and the suction holes 5b are viewed from both ends of the transport belt 2a. As a result, the paper passing over the transport belt 2a is drawn toward the hole 5b, that is, toward the belt 2a, and the transport belt 2a rotates in this state, whereby the paper is transported toward the fixing device 3.

The duct section 5a of the paper suction section 5 is directly connected to the axial fan 6, and the duct section 4a of the ozone suction section 4 branches off from the duct section 5a. An on-off valve is arranged at this branch position.

FIG. 3 shows a cross-sectional structure of the on-off valve driving section 7.
FIG. 3A shows a state where the on-off valve at the branch position is opened, and FIG.
(B) shows a state in which the on-off valve is closed. The on-off valve drive unit 7 includes a rotating shaft 7a rotatably supported. An actuator 7b for detecting paper is provided on the rotating shaft 7a.
A detection piece 7c and an on-off valve 7d are provided. A rotational force is applied to the rotating shaft 7a in the direction of arrow A, that is, in the direction in which the actuator 7b is lifted. This urging force is applied using, for example, a spring. The actuator 7b is provided to protrude upward from between the transport belts 2a. In a state where the sheet does not pass on the transport belt 2a, the urging force is applied to the rotating shaft 7a, so that the upper end of the actuator 7b is lifted up as shown in FIG. Looking upwards. However, when the sheet passes over the conveyor belt 2a, the upper end of the actuator 7b is pushed down by the sheet against the urging force of the rotating shaft 7a. The detection piece 7c and the on-off valve 7d are provided on the rotating shaft 7a as described above. When the actuator 7b is pushed down by the paper and the rotating shaft 7a rotates, the detecting piece 7c and the on-off valve 7d
Also rotates at the same time. The detection piece 7c includes a transmission type optical sensor 7
e are arranged to face each other, and in a normal state, the detection piece 7c blocks light from the optical sensor 7e. However, when the actuator 7b is pushed down by the sheet, the detection piece 7c rises and does not block the light of the optical sensor 7e, so that the passage of the sheet can be detected. The opening / closing valve 7d also performs the opening / closing operation by the rotation of the actuator 7b. The on-off valve 7d is provided at a branch portion between the duct portion 4a of the ozone suction portion 4 and the duct portion 5a of the paper suction portion 5. When the sheet is not passing, the on-off valve 7d is open as shown in FIG. However, when the actuator 7b is pushed down by the paper and pivots, the on-off valve 7d pivots and closes the duct 4a of the ozone suction unit 4. As a result, the suction force of the ozone suction unit 4 decreases.

As described above, the actuator 7b pivots when the sheet passes, turns on the optical sensor 7e (the light is no longer cut off), and closes the on-off valve 7d.

That is, the transfer / peeling charger 1
When the sheet reaches the suction belt 2 after passing through the sheet 5, the sheet rotates the actuator 7b to turn on the optical sensor 7e and closes the on-off valve 7d. As a result, a negative pressure is not generated on the ozone suction unit 4 side, and the paper suction unit 5 can obtain a suction force enough to adsorb even small-sized paper.

[0022]

According to the present invention, the open / close valve provided at the branch position between the paper suction unit and the ozone suction unit is operated by the operation of the sheet detection actuator, and the solenoid or the solenoid is used to operate the open / close valve. There is no need to provide a special operation mechanism for connecting the solenoid and the on-off valve. That is, the actuator is originally provided to detect the passage of the sheet for detecting a jam or the like, and the actuator can be used to directly operate the open / close valve. This enables high reliability, cost reduction, and space saving.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a main part of a copying machine including a suction device.

FIG. 2 is an external view of a suction device.

FIG. 3 is a view showing the operation of an actuator and an on-off valve of the suction device.

[Explanation of symbols]

 2 Suction belt 2a Belt 2b, 2c Roller 4 Ozone suction part 4a Duct part 4b (for suction) hole part 5 Paper suction part 5a Duct part 5b (for suction) hole part 6 Axial flow fan 7 Valve drive part 7a Rotating shaft 7b Actuator 7c Detection piece 7d Open / close valve 7e Optical sensor

Claims (1)

(57) [Claims] A duct connected to a negative pressure generator such as a fan is provided at a suction belt position for conveying a sheet to form a sheet suction unit, and the duct is branched to form a corona discharger. An ozone suction unit is formed by piping at a position, an actuator that is pressed when the sheet passes over the suction belt, a rotating shaft that rotates when the actuator is pressed, and an operation of the actuator. A detection unit that performs paper detection, and an on-off valve provided on the rotation shaft and disposed at the branch position, wherein the rotation of the actuator operates the on-off valve at the branch position, and performs paper detection. A suction device characterized by performing.