JPH066369Y2 - Paper feeding device of image forming apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is provided in a sheet feeding device, and in particular, in an image forming apparatus having a main body upper frame and a lower body frame that can be opened and closed. The present invention relates to a paper feeding device for feeding paper.

[Conventional technology]

2. Description of the Related Art Conventionally, there is a bypass paper feeding device provided separately from cassette paper feeding in order to feed paper in an image forming apparatus such as a copying machine. The bypass sheet feeding device has a stack table for placing sheets on the side surface of the main body, and a plurality of sheets can be placed on the stack table for various sheet sizes. Then, during the copying operation, the sheets placed on the stack table are conveyed by the forward feed roller, and are conveyed one by one to the main body image forming section by the sheet feed roller and the friction pad.

In order to improve the paper feeding performance and to reduce the area occupied by the machine, the stack table in such a system is inclined and arranged with its rear end portion raised.

[Problems to be solved by the invention]

By the way, in copiers and the like, in order to improve workability during jam handling or machine replacement inside, a so-called clamshell type in which the upper frame and the lower frame of the main body can be opened and closed by a predetermined angle There is something called. That is, normally, as shown in FIG. 7 (a), when the upper frame 2 and the lower frame 1 are closed, a copying operation or the like is performed, and when jamming or the like, the same figure is used.
As shown in (b), it is possible to mutually swivel around a fulcrum at one end of the side surface.

However, if such a clamshell type device is provided with the bypass paper feeding device as described above, after opening the upper frame 2 and the lower frame 1 for jam removal and the like, when both frames are closed again. There is a problem that a jam is displayed or multiple sheets are fed.

This will be described in detail with reference to FIG. In the normally closed state, the paper feed roller 6 is in contact with the friction pad 7 provided on the lower frame 1 of the main body, and the paper is sandwiched between the both to convey the paper inside the main body. However, since the paper feed roller 6 is attached to the upper frame 2 side so as to easily remove the jammed paper, the paper feed roller 6 is opened when the upper frame 2 is opened during jam processing or the like. At the same time, it is lifted up as shown by the chain double-dashed line in FIG. In such an opened state, a large gap is generated between the paper feed roller 6 and the friction pad 7, and the sheet 9 is discharged from the stack table 4 whose rear end is lifted and set as described above. It will pass and get inside the device. At the position where this paper enters,
A jam display switch (not shown) is provided, and the switch is turned on by the sheet that has entered. If the operator does not notice this and removes the previously jammed paper and then closes the upper frame, the device will again display a jam. Even if the jam display is not displayed, a plurality of sheets will be supplied.

An object of the present invention is to prevent an image forming apparatus having an openable upper frame and a lower frame from entering a sheet on a stack table into the image forming apparatus when the upper frame is opened.

[Means for solving problems]

A sheet feeding device of an image forming apparatus according to the present invention is a device that is provided in an image forming apparatus having a body upper frame and a body lower frame that can be opened and closed, and that feeds a sheet into the image forming apparatus. The sheet feeding device includes a stack table, a sheet feeding roller, a double feed preventing mechanism, a locking member, and an interlocking mechanism. The stack table is mounted on the lower frame of the main body so that the upstream side in the paper transport direction inclines downward,
A paper is placed on it. The paper feed roller is mounted on the upper frame of the main body and sends the paper on the stack table into the image forming apparatus. The double feed prevention mechanism is mounted on the lower frame of the main body and is a mechanism for preventing double feed of sheets. The locking member prevents the paper on the stack table from entering the inside of the image forming apparatus beyond the paper feed roller and the double feed prevention mechanism, and prevents the paper from entering the inside of the image forming apparatus. It can take a second position that allows. The interlocking mechanism is a mechanism that positions the locking member in the first position when the upper frame of the main body and the lower frame of the main body are in the open position, and positions the locking member in the second position when the upper frame and the lower frame of the main body are in the closed position.

[Action]

In the paper feeding device of the image forming apparatus according to the present invention, when the upper frame of the main body is opened, the interlocking mechanism positions the locking member at the first position. When the locking member is located at the first position, the locking member prevents the sheets on the stack table from entering the image forming apparatus beyond the paper feed roller and the double feed prevention mechanism. It On the other hand, in a normal state in which the upper frame of the main body and the lower frame of the main body are closed, the interlocking mechanism positions the locking member at the second position. When the locking member is located at the second position, it does not hinder the conveyance of the sheet. Therefore, the sheets on the stack table are fed inside the image forming apparatus.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a copying machine as an image forming apparatus according to an embodiment of the present invention. The body frame of the copying machine is composed of a lower frame 1 and an upper frame 2, and a paper feed line is defined with a paper conveying line as a boundary. It is configured so that it can be swung by a predetermined angle around the hinge portion 15 provided on the. An original table 3a on which an original to be copied is placed is provided on the upper surface of the upper upper frame 2, and an original holder 3b is openably and closably mounted on the original table 3a. Further, a stack table 4 is provided on the side surface on the paper feed side of the copying machine body, and a paper discharge tray 5 is provided on the side surface on the discharge side.
The stack table 4 is arranged so as to be inclined so that the upstream side (the right side in FIG. 1) in the sheet feeding direction is higher than the downstream side. Further, the discharge tray 5 has its tip (downstream end).
Are arranged so that they are on the upper side.

The inside of the main body frame will be briefly described. A photoconductor drum 21 is provided at a substantially central portion, and the photoconductor drum 2 is provided around the photoconductor drum 21.
1 main charging corona discharger 22 for charging the surface to a predetermined charge, developing device 23 for developing an electrostatic latent image formed by exposure by an optical system (not shown), transfer for transferring a toner image to a sheet Corona discharger 24a, photoconductor drum 2
A separation corona discharger 24b for separating the copy paper from the surface of No. 1 and a cleaning device 25 for removing the residual toner on the photosensitive drum 21 are provided. Further, at the lower part inside the main body frame, there are rollers 2 for conveying the paper.
A conveying device including 6a, a guide member 26b, a conveying mechanism 26c, and the like is arranged, and a fixing device 27 and a discharging roller pair 28 are arranged on the downstream side (discharging side) of the conveying device.

Next, the bypass sheet feeding portion will be described. A roller 6 for bypass sheet feeding and a friction pad 7 as a double feed preventing mechanism which is pressed against the bypass sheet feeding roller 6 are provided at the sheet feeding side end of the transport system, and the upper sheet feeding roller 6 is provided on the upper frame 2 and the friction pad. The lower frame 1 is provided with 7. The friction pad 7 is the third
As shown in the figure, it is fixed on the receiving table 7a, and the receiving table 7a is constantly urged by the pad pressing spring 8 toward the sheet feeding roller 6 side. A locking member 10 is provided below the pedestal 7a, and the locking member 10 is provided with a spring 11 provided below the locking member 10.
Is urged upward by. The locking member 10 is the fourth
As shown in the figure, a plurality of locking portions 10a are provided at predetermined intervals in the roller axis direction of the paper feed roller 6, and when the upper frame 2 is opened, the locking portions 10a prevent the entry of paper. Has become. The friction pad 7 and its cradle 7a
As shown in FIG. 4, the locking portion 10 of the locking member 10 is
A hole through which a passes is formed. 19 is paper 9
Is a pre-feed roller that conveys the paper to the paper feed roller 6.

Further, an operating lever 14 is rotatably attached above the locking member 10 of the upper frame 2, and as shown in detail in FIG. 2, when the upper frame 2 is in a closed state (normal state). The lower end of the operating lever 14 is configured to come into contact with the upper end of the locking member 10. On the other hand, a lever 12 for opening the upper frame is rotatably mounted above the discharge side of the upper frame 2, and the lever 12 for opening the upper frame and the operating lever 14 are interlocked via an arm 13. It is like this. Further, an upper frame fixing lever 16 is connected to the upper frame opening lever 12,
The lower frame 1 is provided with an upper frame fixing lever locking portion 17 to which the tip of the upper frame fixing lever 16 is locked. The upper frame opening lever 12 is biased clockwise in the drawing.

Next, the operation will be described.

In a normal state such as a copying operation, the upper frame 2 is in a closed state, and the tip of the upper frame fixing lever 16 is locked by the upper frame fixing lever locking portion 17 and the lower frame 1. The upper frame 2 is locked. In this closed state, as shown in detail in FIGS. 2 and 3, the lower end of the operating lever 14 contacts the upper end of the locking member 10, and the upward movement (projection) of the locking member 10 is restricted. Has been done. That is, the locking member 10 prevents the friction pad 7 from interfering with the sheet conveyance.
It is stored below. Then, the paper feed roller 6 and the friction pad 7 are pressed against each other by the friction pad pressing spring 8, and the sheets of the stack table 4 conveyed by the forward feed roller 19 are conveyed one by one inside the apparatus by these.

Next, when a jam or the like occurs and the upper frame 2 is opened, the operator operates the upper frame opening lever 12 against the urging force of a spring (not shown) so as to prevent the upper frame 2 from opening as shown by an arrow A in FIG. It is rotated clockwise. As a result, the upper frame fixing lever 16 shown in FIG. 1 moves downward, its tip is released from the lever locking portion 17, and the upper frame 2 can be opened. At the same time, the arm 13 connected to the upper frame opening lever 12 moves to the right in FIG.
As a result, the actuating lever 14 rotates clockwise around the fulcrum 14a (see the chain double-dashed line in FIG. 2). Therefore, the lower end of the operating lever 14 that was in contact with the upper end of the locking member 10 is released, the restriction by the operating lever 14 is released, and the locking member 10 is projected above the friction pad 7 by the spring 11, as shown in FIG. The state is as shown. At this point, the paper does not enter the downstream side from the nip position between the paper feed roller 6 and the friction pad 7.

After that, the upper frame 2 is opened as shown in FIG. FIG. 6 shows an enlarged view of the bypass sheet feeding section at this time, and the sheet feeding roller 6 is lifted upward to form a large gap with the friction pad 7, but the sheet is locked by the locking member 10. The stop 10a prevents entry into the apparatus.

When the jamming process and the like are finished and the upper frame 2 is closed, the upper frame 2 may simply be swung downward in the same state. That is, the upper frame opening lever 12 has returned to the state shown by the solid line in FIG.
Similarly, due to the position of its center of gravity, is also located in the state shown by the solid line in FIG. Therefore, when the upper frame 2 is closed, the lower end of the actuating lever 14 pushes the upper end of the locking member 10 as shown by the solid line in FIG. It is stored in a position that does not interfere with transportation.

In this embodiment, even when the upper frame is opened, the locking member 10 prevents the sheets from entering the inside of the apparatus, so that it is possible to eliminate the multiple sheet feeding or the jam after the upper frame is opened. In particular, in this embodiment, since the upper frame opening lever 12 and the locking member 10 are interlocked with each other, the locking member 10 can be locked only by operating the upper frame opening lever 12 before opening the upper frame 2. It is possible to project the sheet onto the sheet conveying path and completely prevent the sheet from entering.

In the above embodiment, the locking member is made to project in conjunction with the upper frame opening lever. For example, a member for pressing the locking member (corresponding to the operating lever 14) is used as the upper frame. When the upper frame is opened, the member releases the restriction of upward protrusion of the locking member,
When closing, the tip of the locking member may be pressed by the member so that the locking member is housed in the lower frame. In short, if the protrusion of the locking member is interlocked with the opening of the upper frame. The object of the present invention can be achieved.

Further, in the above embodiment, the case where the protruding member is provided below the friction pad has been described, but the mechanism and installation position of this locking member are not limited to those in the above embodiment.
For example, the locking member may project from the lateral direction to the transport path.

[Effect of device]

As described above, according to the present invention, in the clamshell type image forming apparatus provided with the bypass sheet feeding mechanism, the locking member that appears in and out of the sheet conveyance path is provided in association with the opening / closing operation of the upper frame of the main body. When the upper frame is opened, the above-mentioned locking member is made to project onto the paper transport path, so that it is possible to prevent the paper from entering the inside of the device when the main frame is opened, and eliminate multiple paper feed and jams after opening the main frame. There is an effect that can be.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an image forming apparatus according to an embodiment of the present invention, FIG. 2 is a diagram showing a relationship between an upper frame opening lever and a locking member, and FIG. 3 is a bypass supply in an upper frame closed state. FIG. 4 is an enlarged view of the paper section, FIG. 4 is an enlarged cross-sectional view of the bypass paper feed section when the locking member is projected in conjunction with the upper frame opening lever, and FIG. 5 is the entire apparatus with the upper frame open. FIG. 6, FIG. 6 is a view showing a bypass sheet feeding section in an upper frame open state, FIGS. 7 (a) and 7 (b) are external views showing a general clamshell type image forming apparatus, and FIG. FIG. 6 is a diagram showing a conventional bypass sheet feeding section. 1 ... Main body lower frame, 2 ... Main body upper frame, 4 ... Stack table, 6 ... Paper feed roller, 7 ... Friction pad, 10
...... Locking member, 11 ...... Spring, 12 ...... Upper frame opening lever, 13 ...... Arm, 14 ...... Operating lever

Claims (2)

[Scope of utility model registration request] 1. A sheet feeding device provided in an image forming apparatus having an openable and closable main body upper frame and a lower body main frame, for feeding paper into the image forming apparatus, wherein A stack table on which the sheets are placed so that the upstream side in the transport direction is inclined downward, and a sheet feed roller which is attached to the upper frame of the main body and which feeds the sheets on the stack table into the image forming apparatus. A double feed prevention mechanism mounted on the lower frame of the main body for preventing double feed of the sheets; and a sheet on the stack table passing over the paper feed roller and the double feed prevention mechanism, inside the image forming apparatus. A locking member capable of having a first position for preventing the sheet from entering the inside of the image forming apparatus and a second position for allowing the sheet to enter the inside of the image forming apparatus; When said locking The wood in the first position, the sheet feeding device of an image forming apparatus and a coupling mechanism to position the locking member to the second position when the closed position. 2. The image forming apparatus further comprises a lever for opening the main body upper frame and the main body lower frame, and the interlocking mechanism is interlocked with the operation of the lever. The sheet feeding device of the image forming apparatus according to claim 1, wherein a member is located at the first position and the second position.