JPH059732Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an image forming apparatus in which a heat roller fixing device and a paper discharge section for guiding paper discharged from the heat roller fixing device to the outside of the machine are respectively pivotally mounted to the main body of the device.

Prior Art A heat roller fixing device and a paper discharge section that guides the paper discharged from the machine to the outside of the machine are each pivoted to the main body of the device by shafts parallel to the rollers of the fixing device, and the paper discharge section is opened.
Image forming apparatuses such as copying machines and printers have been known in the past, in which the fixing roller pair is separated by tilting the fixing device from a predetermined mounting position to perform maintenance of the fixing device and paper ejecting section and processing of jammed paper. It is being

However, in conventional image forming apparatuses of this type, when the fixing device is folded down after opening the paper ejecting section, there is no means to appropriately regulate the rotation angle of the fusing device, so the fixing device does not eject the paper. It was difficult to maintain the fixing device in a position convenient for maintenance and inspection.

In addition, when maintenance and inspection are completed and the fixing device is reset, the paper ejecting section may be closed without the fixing device being securely set in the specified mounting position, and the paper ejecting unit may become inoperable, and this may be noticed and the paper ejecting unit may be re-installed. There were drawbacks such as having to open the section and set it again.

Purpose The present invention eliminates the above-mentioned drawbacks of the conventional image forming apparatus having the above configuration. When the paper ejection section is opened and the fixing device is tilted down, the fixing device is held at an appropriate rotational angle position, and the fixing device is fixed when resetting. It is an object of the present invention to provide an image forming apparatus that can be reliably set at a predetermined position.

Configuration In order to achieve the above object, the present invention arranges the pivot shafts of the fixing device and the paper ejection section at different positions in the image forming apparatus having the above structure, so that when the paper ejection section is opened, the fixing device is The present invention is characterized in that a pair of position regulating members are provided on the fixing device side and the paper discharging section side, respectively, to regulate the rotation angle and set the fixing device at a predetermined mounting position when the paper discharging section is closed.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 shows a fixing device of an embodiment of an image forming apparatus to which the present invention is applied, and a configuration near a paper discharge section that guides paper discharged from the fixing device to the outside of the machine.

The fixing device 1 is a heat roller fixing device having a roller pair of a fixing roller 7 and a pressure roller 8, and the fixing device side plate 1a has its lower end connected to the image forming device by a shaft 2 parallel to the axis of the fixing roller. It is pivoted to the main machine frame. The lower end of the paper discharge section 3 is pivotally connected to the frame of the main body of the apparatus via a shaft 4 which is also parallel to the axis of the fixing roller. The axes 2 and 3 mentioned above are located apart from each other.

A fixing roller 7 is rotatably supported on the side plate 1a of the fixing device 1, and a pressure roller 8 is supported on a pressure lever 5 that is swingably attached to the side plate 1a via a pin 13. In the normal mounting state shown in the figure, the tip of the pressure lever 5 is pushed up by a compression spring 6 whose one end is fixed to the main body of the apparatus, and the pressure roller 8 is pressed against the fixing roller 7 to obtain the nip width necessary for fixing. It's starting to become easier. The fixing device 1 including the fixing roller 7 is prevented from rotating clockwise around the shaft 2 due to the pressure contact force of the pressure roller 8 by the compression spring 6, and in order to maintain a predetermined mounting position, the fixing device 1 is fixedly fixed. The device 1 has a hook 9 whose one end is pivotally attached to the upper end of the side plate 1a, and the tip of which is hooked to a pin 10 fixed to the machine frame. Reference numeral 14 in FIG. 1 is a photoreceptor belt, and 15 is a transfer charger. The toner image formed on the photoreceptor belt 14 is transferred to the transfer charger 1.
5 onto the transfer paper, and the fixing roller pair 7, 8
is transported to and fixed.

Now, if a paper jam occurs in the fixing device 1 or if maintenance is to be performed, open the paper discharge section 3 by rotating it to the position shown by the chain line in FIG. Fix and hold. Then, the hook 9 of the fixing device 1 is removed from the pin 10, and the fixing device 1 is rotated about the pin 1 from the normal position shown by the chain line in FIG. 2 to the position shown by the solid line.
At this time, the fixing device 1 is moved so that the fixing device 1 stops at a predetermined position shown by the solid line and maintains that position.
A position regulating pin 11 is provided on the side plate 1a, and a position regulating member 12 is fixedly provided on the paper discharge section 3, with which the position regulating pin 11 comes into contact when the fixing device is rotated as described above in the open position. There is. Since the pivot shafts 2 and 4 of the fixing device 1 and the paper discharge section 3 are separated from each other, the point of contact of the position regulating pin 11 with the position regulation member 12 is at the paper discharge section which is far from the pivot shaft 2 of the fixing device 1. It can be placed close to directly above the pivot shaft 4, and the moment around the shaft 4 due to the weight of the heavy fixing device 1 can be reduced. As a result, excessive stress is prevented from being generated in the paper discharge section.

When the fixing device 1 is in the state shown in FIG. 2, the pressure lever 5 and the pressure roller 8 rotate slightly counterclockwise around the pin 13 due to their own weight, stop at a stopper (not shown), and the fixing roller 7 and pressure roller 8 are separated, and the jam paper can be removed.

After maintenance and removal of jam paper are completed, the fixing device 1 is raised and the paper ejecting section 3 is closed. , position regulation pin 1 on the fixing device side
1 and the position regulating member 12 on the paper discharge section 3 side are brought into contact again.

Therefore, when resetting, if you try to close the paper ejection section 3 while the securing device 1 has not been completely returned to the predetermined mounting position as shown in FIG. 3, it will not close completely. The position regulating member 12 comes into contact with the position regulating pin 11 in the state where the position regulating member 12 is in contact with the position regulating pin 11, and as the paper discharging section 3 is closed, the fixing device 1 is pushed by the paper discharging section 3 via the position regulating pin 11 and moves counterclockwise. Then, the hook 9 is engaged with the pin 10, and the fixing device is reliably reset to the predetermined mounting position.

Effects As described above, according to the present invention, the fixing device is positioned and held at a predetermined appropriate position during maintenance or when processing jam paper, and excessive force is not applied to the paper ejection section that carries the weight of the fixing device. Furthermore, when returning the fixing device to its original position, even if the paper ejection section is closed without returning it correctly, it can be automatically and reliably set in the correct position.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of the present invention, and FIGS. 2 and 3 are explanatory views explaining its operation, respectively. 1... Fixing device, 2... Fixing device pivot shaft, 3...
...Sheet discharge section, 4...Sheet discharge section pivot shaft, 7...Fixing roller, 8...Pressure roller, 11...Position regulation pin,
12...Position regulating member.

Claims (1)

[Scope of utility model registration request] A fixing device having a pair of rollers and a paper discharge section for guiding the paper discharged from the fixing device to the outside of the machine are respectively pivotally connected to the main body of the apparatus by shafts parallel to the axis of the rollers of the fixing device, and the paper discharge section is opened. In an image forming apparatus in which the roller pair is separated by tilting the fixing device from a predetermined mounting position, the pivot shafts of the fixing device and the paper ejection section are arranged at different positions, and the paper ejection section is moved away from the image forming apparatus. When opened, the rotation angle of the fixing device is regulated, and when the paper ejecting section is closed, the fixing device is set at a predetermined mounting position. A pair of position regulating members that engage with each other are attached to the fixing device side and the paper ejecting section side. An image forming apparatus characterized in that each of the image forming apparatuses is provided with an image forming apparatus.