JPH0814738B2 - Image forming device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an electrophotographic image forming apparatus,
More specifically, the present invention relates to an image forming apparatus characterized by an internal heat discharging mechanism.

(Prior Art) In an image forming apparatus such as a printer or a copying machine adopting an electrophotographic system, in order to reduce the installation space, a recording paper is used as disclosed in, for example, Japanese Patent Laid-Open No. 62-102258. It has been proposed that a paper conveyance path is provided obliquely downward so that the paper can be inserted from above and discharged from below the front surface.

However, in the case of such a configuration, the fixing unit located below the series of process units causes the high temperature gas generated inside to flow upward along the paper conveyance path, so that toner that is relatively heat-sensitive and This causes an inconvenience that the photoconductor or the like is affected by this heat and its life is greatly shortened.

(Problems to be Solved by the Invention) The present invention has been made in view of such problems, and an object thereof is to effectively remove internal heat without increasing the size of the device. It is to provide a new image forming apparatus.

(Means for Solving the Problems) That is, the present invention is an image forming apparatus for achieving the above-mentioned problems, in which a fixing unit provided in a part of a paper conveyance path extending obliquely downward is provided diagonally inward. In addition, an exhaust fan for discharging at least the heated gas generated in the fixing unit to the back surface of the apparatus main body is provided in the portion located directly below the photoconductor.

(Example) Then, the Example of this invention is described below.

Each of the drawings shows an embodiment of the present invention.

The outer case shown by reference numeral 1 in the drawing is formed as a vertically long substantially rectangular parallelepiped, and inside the outer case, a pair of registration rollers 2.2 and a pair of discharge rollers 3.3 are arranged vertically, respectively. A paper conveyance path 4 extending obliquely downward so that the recording paper pulled in from the upper part of the paper is discharged along the front surface of the photosensitive drum 10 to the lower front surface of the outer case 1.
Are formed.

The front surface of the outer case 1 is covered with a front cover 6 that opens and closes with the paper transport path 4 as a boundary. The outer case 1 also includes a cleaning unit 11 and an eraser 1.
2, the charger 13, the optical writing unit 14, and the developing unit 15 that are involved in a series of electrophotographic processes surround the photoconductor drum 10 and the paper transport path 4
The transfer charger 16 and the fixing unit 17 are provided at the corresponding positions of the paper transport path 4 on the inner side of the front cover 6 described above.

By the way, reference numeral 20 in the drawing denotes an exhaust fan disposed obliquely inward of the fixing unit 17 and immediately below the axial center position of the photosensitive drum 10. The exhaust fan 20 is fixed like a well-known sirocco fan. The heating gas is directly sucked from the entire longitudinal direction of the unit 17, and while the gas is brought into contact with the waste toner box of the cleaning unit 11, the suction force is directly applied from the gap between the fixing unit 17 and the cleaning unit 11. A fixing unit that acts on the paper transport path 4
The heating gas rising from 17 toward the photoconductor drum 10 is discharged to the back surface of the apparatus main body (second
Figure).

In the figure, reference numeral 18 indicates a power source arranged at the bottom of the outer case 1, and reference numeral 19 indicates a controller board.

In the apparatus configured as described above, the toner image formed on the photoconductor drum 10 is transferred onto the recording paper fed from the upper part of the outer case 1, and then the space between the heating roller and the pressure roller in the fixing unit 17 is transferred. After a series of image forming operations for fixing the toner image while applying heat and pressure to the recording paper through the outer case 1 is filled with the heated gas generated in the fixing unit 17, as described above, Since the exhaust fan 20 is provided diagonally inward, the heated gas generated in the fixing unit 17 is directly sucked by the exhaust fan 20 together with the heated gas generated from the power source 18 and discharged to the rear surface of the apparatus main body. The heated gas that is going to rise from the fixing unit 17 to the cleaning blade 11a, the photoconductor drum 10, and the developing unit 15 along the paper transport path 4 is fixed. From the gap between the unit 17 and the cleaning unit 11, it is effectively sucked by the suction force directly acting on the paper conveyance path 4 and discharged to the back surface of the apparatus main body, and there is no influence of heat on the photoconductor drum 10 or toner. To

(Effect) As described above, according to the present invention, in an image forming apparatus provided with a paper conveyance path that extends obliquely downward, it occurs internally in a portion located diagonally below the fixing unit and directly below the photoconductor. Since an exhaust fan for discharging the heated gas to the back of the apparatus main body is provided, this type of exhaust fan having a relatively large volume can be easily used by utilizing the trapezoidal space formed inside the paper transport path. Not only can it be housed, but the exhaust air can be prevented from directly hitting the user by making the exhaust direction the rear surface of the apparatus main body.

Moreover, the heated gas generated in the fixing unit can be directly sucked and removed in the vicinity of it together with the heat from the power supply, and the suction force of the exhaust fan can be directly applied to the paper conveyance path without being obstructed by the fixing unit. As a result, the heated gas rising from the fixing unit to the photoconductor through the paper conveyance path can also be effectively sucked and removed, and the adverse effect of heat on the toner and the photoconductor can be reliably suppressed.

[Brief description of drawings]

FIG. 1 is a perspective view of an apparatus showing an embodiment of the present invention, and FIG. 2 is a view showing a schematic configuration of the same apparatus. 1 ... Exterior case, 4 ... Paper transport path 10 ... Photosensitive drum, 17 ... Fixing unit 20 ... Exhaust fan

Continuation of front page (56) Reference JP-A-55-155378 (JP, A) JP-A-59-53876 (JP, A) JP-A-56-151560 (JP, A) JP-A-61-175649 (JP , A) JP 62-102258 (JP, A) JP 48-29445 (JP, A) JP 56-27184 (JP, A) JP 59-133557 (JP, A) JP 61-56371 (JP, A) Actually opened 61-114464 (JP, U) Actually opened 53-155642 (JP, U) Actually opened 55-172939 (JP, U) Actually opened 63-33158 (JP, U) JP-B 47-26349 (JP, B1) JP-B 58-43741 (JP, B2) JP-B 55-50285 (JP, B2) JP-B 62-50824 (JP, B2) JP-B 52 -43103 (JP, B2) Actual public 49-11955 (JP, Y1) Actual public 52-41391 (JP, Y2) Actual public 52-25152 (JP, Y2)

Claims (1)

[Claims] 1. An image forming apparatus provided with a paper conveying path extending obliquely downward so that recording paper fed from above an outer case is discharged along a front surface of a photoconductor to a lower front side of the outer case. Exhaust gas that discharges at least the heating gas generated in the fixing unit to the rear surface of the apparatus main body at a portion diagonally inward of the fixing unit provided in a part of the transport path and directly below the photoconductor. An image forming apparatus having a fan.