JP2549650Y2 - Image forming device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus, such as a copying machine or a printing machine, having a mechanism for feeding sheets one by one from a sheet tray in an orderly manner.

[0002]

2. Description of the Related Art Papers used in copying machines, printing machines, and the like are roughly classified into rolls and sheets. Among them, sheet-shaped paper is stored in a paper tray and is sent out one by one. At this time, if the leading ends of the sheets on the sending side are not aligned, a double feed in which a plurality of sheets are sent out at the same time, a skew in which the sheets are sent in a state inclined in the transport direction, and the like occur.

Therefore, in order to align the edges of the sheet, a method in which a sheet leading end positioning member is brought into contact with the edge of the sheet by an independent mechanism as shown in FIG. That is, the sheet leading end positioning member 33 which comes into contact with the sending side end of the sheet 32 stored in the sheet tray 31 is arranged to be vertically movable by a link mechanism incorporating a solenoid 34. The sheet 32 in the sheet tray 31 is set at a predetermined position by the sheet leading end positioning member 33 abutting on the end of the sheet 32.

When the sheet 32 is sent out from the sheet tray 31, a sheet leading end positioning member 33 is operated by a solenoid 34.
Is lowered, and the paper feed roller 35 is lowered to make the paper 32
Contact the upper surface of the The paper 32 is a paper feed roller 3
5 rotates the paper feed roller 3 from the paper tray 31
It is sent to 6. A friction pad 37 is pressed against the paper feed roller 36, and by utilizing the fact that the frictional force between the paper 32 and the friction pad 37 is larger than the frictional force between the papers 32, the papers 32 are conveyed one by one. I have.

[0005]

However, the paper tip positioning member 3 driven by the independent mechanism as described above.
Incorporating 3 into a copier or printing machine complicates the structure of the apparatus. In addition, the effective space inside the device is reduced, and operations such as maintenance and inspection are troublesome. Looking at the drive mechanism itself of the sheet leading edge positioning member 33, the solenoid 34 and the link mechanism are required, which not only causes an increase in cost, but also raises and lowers the paper feeding roller 35 by moving the sheet leading edge positioning member 33 up and down by the solenoid 34. Need to be synchronized. If the synchronization is incomplete, the reliability of the device is reduced. However, in order to perform the synchronization completely, a control system incorporating a corresponding program is required.

In view of the above, the present invention provides a special mechanism for driving the sheet leading end positioning member by mechanically connecting the timing at which the positioning member abuts on the end of the sheet with the elevation of the sheet feeding roller. Without using
It is an object of the present invention to provide an image forming apparatus having a paper feed mechanism for aligning the edges of sheets with a simple mechanism.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a paper tray on which paper is stacked, and a paper tray for feeding paper loaded on the paper tray.
A shaft that moves toward
It is, an engaging portion positioning portion and the other for positioning the sheet edge of the sheet to one with respect to the axis, by rotational force of the sheet feeding direction of the positioning portion to the opposite direction to its own weight connexion A paper leading end positioning member that sets the position of the center of gravity to be generated, and the shaft is provided separately from the shaft.
The leading edge of the sheet until it moves toward the sheet tray
By engaging with the engaging portion of the positioning member,
A stopper for restricting rotation of the paper leading end positioning member .

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The features of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a state in which the sheet leading end positioning member is in contact with the end of the sheet in the image forming apparatus of the embodiment of the present invention. The positioning portion 3a of the sheet leading end positioning member 3 abuts on the sending-out end face of the sheet 2 placed on the sheet tray 1. The sheet leading end positioning member 3 is swingably mounted on a shaft 5 of a feeding roller 4 which is arranged above the sheet tray 1 so as to be able to move up and down. At the upper end of the sheet leading end positioning member 3, an engaging portion 3b is formed which engages with a stopper 6 provided above the feeding roller 4.

The center of gravity of the sheet leading end positioning member 3 is
It is set on the left side of FIG. 1 with respect to the mounting portion 3c for the shaft 5. Therefore, in the free state, the sheet leading end positioning member 3 hangs down from the shaft 5 with the positioning portion 3a down, and receives a counterclockwise rotational force. With this force, the end faces of the paper 2 are aligned. The clockwise rotation is restricted by the stopper 6.

In the state shown in FIG. 1, since the positioning portion 3a of the paper leading end positioning member 3 is in contact with the end surface of the paper 2, the paper 2 stored in the paper tray 1 is positioned by the positioning portion 3a. . When the feed roller 4 is lowered from this state, the engagement state of the engagement portion 3b with the stopper 6 is released, and the sheet leading end positioning member 3 becomes swingable.

Further, when the feed roller 4 is lowered and brought into contact with the upper surface of the uppermost sheet 2, the sheet 2 is sent out of the sheet tray 1 by the rotation of the feed roller 4.
At this time, the sheet leading end positioning member 3 is inclined as shown in FIG. 2 with the movement of the fed sheet 2. Then, the paper 2 that has passed through the lower end side of the positioning section 3a passes between the feed roller 7 and the friction pad 8, and is conveyed one by one to a copying or printing process.

When the copying or printing operation is completed, the operation of the operation board raises the feed roller 4 from the state shown in FIG. 2 in contact with the sheet 2 to the state shown in FIG. At this time, since the center of gravity of the paper leading end positioning member 3 is on the left side of the shaft 5, the paper leading end positioning member 3
The feed roller 4 turns counterclockwise with the rise of the feed roller 4. Then, when the feed roller 4 continues to be raised while the engaging portion 3b is standing up, the engaging portion 3b returns to the state of FIG.

Then, based on the positional relationship between the center of gravity of the paper tip positioning member 3 and the shaft 5, the paper tip positioning member 3
, A slight counterclockwise rotation is applied. With this power,
The end surfaces of the sheets 2 in the sheet tray 1 are aligned again.
In order to surely perform the swinging of the sheet leading edge positioning member 3 and the engagement with the stopper 6 described above, the engagement distance L1 between the engagement portion 3b and the stopper 6 is set to the engagement portion 3
It is preferable to make the distance smaller than the minimum moving distance L2 of the feed roller 4 in consideration of the distance in which b rises while maintaining the standing state.

[0014]

As described above, in the present invention, the ends of the sheets stored in the sheet tray are aligned by the sheet leading end positioning member which swings in accordance with the elevation of the feed roller. Therefore, it is not necessary to move the sheet leading end positioning member by a dedicated driving mechanism as in the related art, which not only simplifies the structure, but also abuts the sheet leading end positioning member on the sheet end and the feeding roller of the sheet. Synchronization with lifting is ensured. For this reason, it is possible to perform operations such as alignment of sheet edges and sheet sending with high reliability with a simple equipment configuration. In addition, since the rotating force acts so that the positioning portion of the sheet leading end positioning member returns to the positioning position by its own weight, there is no need to provide a complicated mechanism. Therefore, an image forming apparatus having high reliability with a simple configuration can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a state in which a sheet leading end positioning member is in contact with an end of a sheet in the image forming apparatus according to the embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing a state in which paper is being sent from a paper tray.

FIG. 3 is a schematic sectional view showing an image forming apparatus provided with a conventional sheet leading end positioning member.

[Explanation of symbols]

 1: paper tray 2: paper 3: paper leading end positioning member 3a: positioning part 3b: engaging part 3c: mounting part 4: feed roller 5: shaft 6: stopper 7: feed roller 8: friction pad

Claims (3)

(57) [Scope of request for utility model registration] A sheet tray on which sheets are stacked; and a sheet tray on which the sheets stacked on the sheet tray are sent out.
A shaft that moves toward a paper tray, and is rotatably supported by the shaft, and engages with a positioning portion that positions the paper end of the paper on one side with respect to the shaft and the other
And a section, the paper feed direction of the positioning unit is provided as a paper leading positioning member rotational force in the opposite direction is set the center of gravity position to occur One by its own weight, the shaft separately from, the The axis is the paper tray
Until the paper leading end positioning member moves toward
The leading edge position of the paper is determined by engaging the engaging portion.
An image forming apparatus comprising: a stopper for restricting rotation of the member . 2. The method according to claim 2, wherein the center of gravity of the sheet leading end positioning member is a front end.
2. The image forming apparatus according to claim 1, wherein the image forming apparatus is located downstream of the center of the shaft in the sheet feeding direction. 3. The sheet feeding device is provided downstream of a positioning position of the sheet leading end positioning member by the positioning portion in a sheet feeding direction, and conveys the sheets sent by the sheet feeding means one by one toward a copying or printing step. The image forming apparatus according to claim 1, further comprising a separating / conveying member that performs separation.