JP3897090B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus provided with a guide member in which a suction fan for adjusting a posture of a sheet after transfer and inserting it into a fixing unit is installed.
[0002]
[Prior art]
The images formed one by one on the photoconductor are sequentially transferred to the intermediate transfer member at the primary transfer unit and superimposed, and then the paper is sandwiched between the intermediate transfer member and the secondary transfer roller at the secondary transfer unit, 2. Description of the Related Art An intermediate transfer type color image forming apparatus that performs batch transfer is known, and the overall configuration of such an image forming apparatus will be described with reference to FIG.
The photoreceptor (OPC) 1 forms toner images of 1 to 4 colors by a developing device (not shown). The intermediate transfer belt 20 is stretched in a polygonal shape by a cleaner backup roller 21, a tension roller 22, a secondary transfer backup roller 23, a drive roller 26, and a primary transfer support roller 25, and is driven so as to come into contact with the photoreceptor 1 in a forward rotation. The roller 26 is rotationally driven. A primary transfer portion is formed by the photoreceptor 1 and the primary transfer backup roller 24, and the primary transfer support roller 25 cooperates with the primary transfer backup roller 24 to secure a contact pressure with the photoreceptor 1. Primary transfer is performed. The image formed on the photosensitive member 1 is transferred to the intermediate transfer belt 20 one color at a time and is overlaid on the sheet 31 at the secondary transfer portion formed by the secondary transfer roller 30 and the secondary transfer backup roller 23. The images are collectively transferred and fixed by the fixing device 40.
[0003]
In the vicinity of the transfer portion where the secondary transfer roller 30 comes into contact with the intermediate transfer belt 20, a guide 31 incorporating a suction fan 32 for setting the posture of the sheet after transfer and feeding it into the fixing device 40 is installed. ing. Since the suction fan 32 is blowing air in the direction in which the sheet is attracted to the guide 31, the vicinity of the secondary transfer portion has a negative pressure. In the vicinity of the secondary transfer portion, a cleaner member 10 that comes into contact with the intermediate transfer belt at the position of the cleaner backup roller 21 is provided to clean residual toner after secondary transfer and residual toner at the time of jamming. . The cleaner member 10 is composed of a cleaner case 11 that opens to the intermediate transfer belt side, a cleaner blade 12, a cleaner cover 13 that prevents the cleaned waste toner from splashing, and a cleaner rake sheet 14, and is in contact with and separated from the intermediate transfer belt. Residual toner is cleaned and collected.
[0004]
As shown in FIG. 3, the toner collected by the cleaner member 10 is conveyed through a waste toner pipe 15 containing a conveyance screw (not shown) extending from the cleaner case 11, and is discharged from a toner dropping port 16 at the tip of the pipe. It is put into the tank 17 and stored. The waste toner tank 17 has a large pipe insertion opening with respect to the pipe so that the user can easily attach and detach the waste toner tank 17 and replace it before the waste toner overflows. In addition, the waste toner tank can be used as a front door for maintenance so as not to hinder maintenance work, facilitate the removal and installation of waste toner, and improve the efficiency of tank use by smoothing the unevenness of the stored waste toner. May be attached to. In that case, the accuracy of the opening and closing of the door, and the locus of movement of the tank along with the opening and closing becomes an arc, and in order to insert the tank into the fixed waste toner pipe 15, it is necessary to make the pipe insertion port of the waste toner tank considerably large. is there. Therefore, a gap is generated between the waste toner tank pipe insertion opening and the waste toner pipe.
[0005]
A suction airflow generated by a suction fan or a cooling fan in the apparatus generates an airflow around the pipe insertion port of the waste toner tank, and the waste toner is scattered around the tank through a gap between the waste toner pipe and the pipe insertion port. Conventionally, in order to prevent this, a partition wall 35 is provided between various exhaust fans and the waste toner tank so as to isolate the airflow from directly affecting the pipe insertion port of the waste toner tank. These partition walls serve to prevent the user from contacting the inside of the apparatus other than necessary during maintenance, and also to prevent the heat of the fixing unit from being directly transmitted to the waste toner tank.
[0006]
[Problems to be solved by the invention]
However, according to the above-described conventional apparatus configuration, the partition wall 35 formed between the waste toner tank and the area where the suction fan is installed has a gap between the waste toner pipe 15 and the waste toner pipe 15. Air flows in through. Accordingly, the waste toner is sucked by the airflow from the waste toner drop port 16 of the waste toner pipe 15 in the vicinity from the gap, and the toner is scattered in the vicinity of the secondary transfer portion to contaminate the inside of the transfer device and stain the print. There's a problem. In particular, when printing on the second side of double-sided printing, the paper is curled, the posture of entering the fixing is not stable, and the paper is likely to wrinkle. It is necessary to suck it along the guide, so that a stronger air current is generated and the degree of contamination becomes severe.
[0007]
[Means for Solving the Problems]
The present invention has been made to solve the above-described problems, and eliminates the influence of negative pressure on the waste toner tank side by a suction fan to prevent contamination of the transfer unit, the inside of the apparatus, or printing.
[0008]
The present invention extends from a suction fan that adjusts the posture of a sheet placed between a transfer unit that transfers a toner image from an intermediate transfer member to a sheet and a fixing unit, and a cleaning member that faces the intermediate transfer member. In an image forming apparatus in which a waste toner pipe tip is inserted and a partition wall through which the waste toner pipe passes is provided between a waste toner pipe and a waste toner container in which a gap is formed between the waste toner pipe and the pipe insertion port. A seal member for closing a gap between the pipe and the partition wall is provided.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0010]
FIG. 1 is a diagram showing an example of the apparatus configuration of the present invention. The same numbers as those in FIGS. 2 and 3 indicate the same contents.
[0011]
As described with reference to FIGS. 2 and 3, the sheet on which the transfer has been performed from the intermediate transfer belt 20 by the secondary transfer roller 30 is adjusted by the suction fan 31 and is fed into the fixing unit. Residual toner on the intermediate transfer belt 20 is conveyed through a waste toner pipe 15 extending from the cleaner case 11 of the cleaner member 10, and is put into a waste toner tank 17 from a toner drop port 16 at the tip of the pipe and stored. At this time, since there is a gap between the waste toner pipe 15 and the partition wall 35, air flows in through the gap due to the intake airflow generated by the suction fan 31 and the like. Accordingly, the waste toner is sucked by the airflow from the waste toner drop port 16 of the waste toner pipe 15 in the vicinity from the gap, and the waste toner to be put into the tank is scattered.
[0012]
Therefore, in the present invention, a seal 36 that closes the gap between the partition wall 35 and the waste toner pipe 15 is provided. As a result, no airflow is generated on the side of the waste toner tank due to the influence of the suction fan 31 or the like, and the toner to be put into the waste toner tank from the toner dropping port 16 is not sucked and scattered.
[0013]
In the above example, the seal 36 that fills the gap between the partition wall 35 and the waste toner pipe 15 is provided. However, in order to eliminate the toner that falls from the cleaner case and scatters on the transfer portion side, the outer side of the cleaner cover is removed. Further, a plate for obstructing the flow of air may be provided.
[0014]
【The invention's effect】
As described above, according to the present invention, airflow generated by a suction fan or the like can be prevented from being generated in the gap between the waste toner pipe and the partition wall, so that the toner is sucked in the vicinity of the toner drop port of the waste toner pipe. Therefore, the waste toner is stored in the waste toner tank without being scattered, and the transfer device, the inside of the device, or the printing can be prevented from being contaminated.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of a device configuration of the present invention.
FIG. 2 is a diagram illustrating an overall configuration of an image forming apparatus.
FIG. 3 is a diagram illustrating a partition provided between a transfer unit and a waste toner tank.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 15 ... Toner pipe, 16 ... Toner drop port, 17 ... Waste toner tank, 30 ... Secondary transfer roller, 31 ... Guide, 32 ... Suction fan, 35 ... Partition, 36 ... Seal.

Claims (1)

A suction fan that adjusts the orientation of the paper installed between the transfer unit and the fixing unit that transfers the toner image from the intermediate transfer member to the paper, and a tip of the waste toner pipe that extends from a cleaning member that faces the intermediate transfer member There is inserted, between the waste toner container a gap is formed between the waste toner pipe and the pipe insertion port, in an image forming apparatus provided with a partition wall waste toner pipe penetrates, and a waste toner pipe and the partition An image forming apparatus comprising a sealing member for closing the gap.

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