JPH0355966Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a paper feeding and conveying device for an image forming apparatus.

[Conventional technology]

As a paper feed conveyance device of an image forming apparatus, for example, conveyance elements including conveyance rollers and guide plates are arranged at the top and bottom of the paper feed path, and paper is fed to the developing unit side which is configured to be freely drawn out to the front side of the apparatus. There is something I tried to do.

[Problem that the invention attempts to solve]

If the paper fed by the paper feeding and conveying device described above becomes jammed in the vicinity of the developing unit, the developing unit, which is configured to be able to be pulled out to the front of the device, is moved to the front side to facilitate maintenance and inspection. By pulling out the developing unit, the paper jam can be easily cleared through the developing unit pull-out space, but if a paper jam occurs in the paper feeding path of the paper feeding and transporting device, or if the paper is further removed from the paper feeding and transporting device. If a paper jam occurs near the developing unit, it is often difficult to clear the paper jam because the spacing between the upper and lower transport elements is narrow. It was even more difficult to clear the paper jam when the paper was jammed.

The present invention has been devised in view of the above circumstances, and provides a paper feeding and conveying device that can easily eliminate paper jams in the paper feeding path through extremely simple improvements. The purpose is to

[Means for solving problems]

In order to achieve the above object, the present invention provides a paper feeding and conveying device for an image forming apparatus that includes upper and lower conveying elements for feeding paper to a developing unit side that can be freely pulled out to the front side of the apparatus. A conveyance element is provided so as to be able to approach and separate from the conveyance element on the lower side, and the conveyance element on the upper side is positioned at a paper conveyance position for conveying the paper and a space when the developing unit is pulled out to the front side of the apparatus. It is characterized in that it is configured to be movable between the open position and the open position, and is provided with a fixing mechanism for fixing the upper conveyance element at the paper conveyance position, which can be freely fixed and released.

[Effect]

According to the above characteristic configuration, after the developing unit is pulled out to the front side of the apparatus, the upper conveyance element is released from being fixed at the paper conveyance position,
In addition, by separating the upper conveying element from the lower conveying element, the interval between the upper and lower conveying elements increases.

Hereinafter, an embodiment of the present invention will be described based on the drawings. FIG. 1 shows the entirety of an electrostatographic copying machine as an image forming apparatus. Along with opening up
The developing unit A is shown pulled out to the front of the copying machine along the pair of left and right guide members 3, 3.

As shown in FIG. 2, the developing unit A includes a photosensitive drum 4 having a photoreceptor on its surface, a developing device 5, and a cleaning device 6 arranged in a developing unit frame 7.
By pulling out the developing unit A forward, you can not only perform maintenance and inspection of the developing unit A, but also easily clear paper jams near the developing unit A through the developing unit pull-out space. It's getting old.

When the developing unit A is built into the copying machine main body 8, a charging device 9, a transfer device 11, and a separating device 12 are arranged around the photosensitive drum 4, and an upper part of the copying machine main body 8 is provided. is an exposure device 10
is provided. And the developing unit A
Upstream side in the paper feeding direction (right side in Figure 2)
has a paper feed unit B, and the paper feed unit B
A paper feeding conveyance mechanism 1 is provided between the developing unit A and the developing unit A.
3 are arranged respectively.

As shown in FIG. 3, the paper feed unit B includes a loading section 15 for a plurality of cassette cases 14 containing copy sheets of different sizes, a manual feed section 16 for copy paper, and a loading section 15 for storing copy sheets of different sizes. A paper feed roller 17 for feeding copy paper is provided in a pair of front and rear paper feed unit frames 18, and the paper feed unit frame 18 is placed on the extraction side (paper feed side) of the cassette case 14 with respect to the copying machine main body 8. (opposite side)
It consists of a drawer that can be freely pulled out.

The paper feed conveyance device 13 is composed of upper and lower conveyance elements. Specifically, the lower conveyance element includes a lower conveyance roller 20 provided near the paper feed rollers 17 with respect to the paper feed unit frame 18. At the same time, a lower guide plate 22 is disposed between the lower conveyance rollers 20, 20, and the upper conveyance element is positioned corresponding to the lower conveyance roller 20, and is connected to a pair of front and rear conveyance unit frames 23. is provided with upper conveyor rollers 19... and an upper guide plate 21 is arranged between the upper conveyor rollers 19, 19, and by the cooperation of the upper and lower conveyor rollers 19, 20 pairs of both conveyance elements that are in contact with each other. , the copy paper is in the developing unit A
When the paper is fed towards the copy paper and the copy paper becomes jammed between the two transport elements, the paper feed unit frame 18 is moved toward the By pulling out the copy paper from the machine body 8, it is possible to remove the copy paper stuck between the two transport elements through the draw-out space of the paper feed unit B.

On the other hand, the conveying unit frame 23 of the upper conveying element is located near the front and rear side plates 8a of the copying machine main body 8, and its upper side pivots to the copying machine main body 8 about a shaft 24 extending in the front-rear direction. Supported.

The transport unit frame 23 extends between the upper side of the transport unit frame 23 and the copying machine main body 8.
A tension spring 25 is provided for rotating the upper conveying roller 19 and the guide plate 21 upwardly around the shaft 24, and for separating the upper conveying roller 19 and the guide plate 21 from the lower conveying roller 20 and the guide plate 22. At the same time, the transport unit frame 23 is placed in a predetermined position (between the upper and lower transport rollers 19 and 20) against the tension spring 25 between the transport unit frame 23, the lower side, and the copying machine main body 8. Fixing mechanism 2 that fixes with a predetermined nip width)
6 is provided so that it can be freely fixed and released.

Therefore, by switching the fixing mechanism 26 to the unlocked state while the developing unit A is pulled out to the front of the copying machine main body 8, the developing unit A is brought to a position where the paper is transported in cooperation with the lower transport element. The transport unit frame 23 of the upper transport element rotates upward in a state in which it enters the drawer space of the developing unit A, and the upper transport element separates from the lower transport element and transports the upper part. The element is switched to the open position, so that copy paper stuck between the upper and lower pairs of conveying rollers 19 and 20 can be removed through the drawer space of the developing unit A. .

Although the amount of upward rotation of the transport unit frame 23 is limited by the guide member 3 on the right side, in order to increase the amount of rotation as much as possible, Transport unit frame 23
A recess 27 is formed in.

A stopper 28 is provided on the copying machine main body 8 to restrict the amount of rotation of the transport unit frame 23 so that the recess 27 does not come into contact with the guide member 3.

Now, on the operation panel section X at the top of the copying machine main body 8, there is a paper jam display panel _Y1 that separately displays the occurrence of a paper jam near the developing unit A and the occurrence of a paper jam in the paper feed conveyance mechanism 13. , Y ₂ are provided.

Therefore, when a paper jam occurs, it can be determined whether to pull out the developing unit A or the paper feed unit B, and the paper jam can be cleared efficiently.

However, as described above, the paper jam in the paper feed and transport mechanism 13 can also be cleared by pulling out the developing unit A and releasing the fixation from the transport unit frame 23. Of course, it is possible to select clearing the paper jam by pulling out the paper feed unit B, and the panel _Y2 that displays the paper jam in the copy paper transport mechanism 13 is based on the selection criteria for clearing the paper jam described above. It becomes.

Based on the paper jam display on both panels Y ₁ and Y ₂ , it can be determined that the paper jam has occurred from the copy paper transport mechanism 13 to the developing unit A.

Next, regarding the fixing mechanism 26, as shown in FIG.
An L is provided on the transport unit frame 23 at a location corresponding to the locking pin 29 so as to be rotatable around an axis 30 in the front-rear direction.
The L-shaped arm 3 is pivotally connected to the L-shaped arm 3.
1 is provided with a hook a that engages and disengages from the locking pin 29 by rotation of the L-shaped arm 31, and a spring 32 that biases the hook a in the engagement direction; , a stopper 33 is provided on the L-shaped arm 31 for restricting rotation of the L-shaped arm 31 in the disengaged state, and a stopper 33 is provided on the L-shaped arm 31 to limit the rotation of the L-shaped arm 31, and as the stopper 33 An inclined portion b is formed at one end of the L-shaped arm 31 that abuts the locking pin 29, and rotates the hook a in the disengagement direction upon the abutment.

Therefore, by pressing the other end of the L-shaped arm 31 downward, the engagement of the hook a with the locking pin 29 can be released, and when the pressing is released in this state, the tension spring 25 The conveyance unit frame 23 can be rotated upward by the biasing force of , and by pressing the lower side of the conveyance unit frame 23 in this unlocked state, the inclined portion b is moved against the locking pin 29. , the L-shaped arm 31 rotates counterclockwise about the shaft 30, and then the L-shaped arm 31 rotates clockwise due to the biasing force of the spring 32, and the hook a is locking pin 2
9, thereby fixing the transport unit frame 23 at a predetermined position.

[Effect of idea]

As explained above, according to the paper feed conveyance device of the image forming apparatus according to the present invention, after the developing unit is pulled out to the front side of the apparatus, the fixation of the upper conveyance element at the paper conveyance position is released, and , by separating the upper conveying element from the lower conveying element and switching the upper conveying element to an open position, the distance between the upper and lower conveying elements can be increased. Therefore, even if a paper jam occurs between the upper and lower conveyance rollers, where it is most difficult to clear a paper jam, or even if the paper jam occurs between the paper feed and conveyance device and the vicinity of the developing unit, Even if a paper jam occurs, it has become possible to clear the paper jam extremely easily through the drawer space of the developing unit.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is an overall perspective view of the copying machine with the front cover open and the developing unit pulled out, FIG. 2 is an overall longitudinal sectional front view of the copying machine, and FIG. 4 is a sectional view of the main part, and FIG. 4 is a detailed view of the fixing mechanism. 19...Upper conveyance roller, 20...Lower side conveyance roller, 21...Upper guide plate, 22...Lower guide plate, 26...Fixing mechanism, A...Developing unit.

Claims (1)

[Claims for Utility Model Registration] In a sheet feeding and conveying device for an image forming apparatus, which comprises upper and lower conveying elements for feeding paper to a developing unit that can be freely pulled out to the front side of the apparatus, the upper conveying element is The conveyance element on the lower side is provided so as to be close to and separated from the conveyance element on the lower side, and the conveyance element on the upper side is moved to a paper conveyance position for conveying the paper and a space when the developing unit is pulled out to the front side of the apparatus. A supply of an image forming apparatus characterized in that the image forming apparatus is configured to be movable between an open position and a fixing mechanism for fixing the upper conveying element at the sheet conveying position and is detachable from the fixing mechanism. Paper conveyance device. Each of the lower conveying elements has at least one
a lower conveyor roller and a lower guide plate, wherein the upper conveyor element cooperates with the lower conveyor roller and an upper guide plate located opposite the upper conveyor roller and the lower guide plate. A paper feeding and conveying device for an image forming apparatus according to claim 1, which includes the following.