JP2698125B2 - Sheet transport device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to an openable and closable first transport guide plate constituting a first transport path for transporting a sheet, and a second transport path continuous with the first transport path. The present invention relates to a sheet conveying device for an image forming apparatus such as a copying machine, comprising: a second conveying guide plate which is configured and is capable of being opened and closed, and is provided with a driven roller which is pressed against a stationary driving roller.

2. Description of the Related Art Jamming of sheets in a sheet conveying path of a copier or the like.
When the sheet is conveyed by pressing the driving roller and the driven roller, it is necessary to release the pressing of the driven roller. Conventionally, in a transport apparatus having a continuous first transport path and a second transport path, when the driven roller provided to the transport guide plate constituting the second transport path, the first transport path is conventionally opened. By itself, the pressure of the driven roller is not released, and it is necessary to provide a mechanism for releasing the pressure on the second transport guide plate.

However, in such an apparatus, it is necessary to open the first conveyance path and to operate the pressure release mechanism of the second conveyance guide plate, so that a jam operation or the like cannot be performed by a simple operation.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-described problems in the related art, and to provide a sheet conveying apparatus with improved operability in jam processing and the like.

According to the present invention, the engaging portion contacts the first guide plate, the pressing means for pressing the driven roller against the driving roller, and the pressing portion engages the engaging portion at the closed position of the first guide plate to press the pressing means. By providing the engagement member set at the position and the means for holding the position of the second guide plate when the pressure is released, the driven roller can be pressed or released simply by opening and closing the first guide plate. it can.

Embodiment FIG. 1 shows an embodiment in which the present invention is applied to a duplex conveying device of a copying machine.

A transfer sheet P, which is an example of a sheet carrying an unfixed toner image formed by a predetermined copying process, is
After the fixing, the sheet is introduced into a conveying unit which is an example of the sheet conveying apparatus.

The transfer paper P enters the second transport path 2 and passes through the first transport path 1, and when performing one-sided recording, passes through the transport path 3 and is discharged to complete the copy. When double-sided recording is performed, the drive means (not shown) of the branch claw 4 is turned on, the branch claw 4 rotates clockwise, the transfer path 5 passes through, and the transfer paper P passes therethrough and is discharged to the double-sided tray by the discharge roller 6. And stocked in it.

The transfer paper P stocked on the double-sided tray 7 has its leading end position uniformly aligned by an end fence 8 movable for each size. Air A is blown to the leading end of the stocked transfer paper P to float, so that the coefficient of friction between the papers is reduced and the separation performance is improved. As a result, the transfer paper P is sequentially re-supplied while being suctioned to the upper surface of the belt 10 driven at a predetermined timing by the negative pressure unit 9 on the lower surface side in order from the lowest stage.

If the transfer sheet P is jammed, it must be removed.

FIG. 2 shows a state in which the first upper transport unit 20 is opened.

When the transfer paper P is jammed, by opening the first upper conveyance unit 20 around the fulcrum 20a, the driven roller 20b is released together with the first upper conveyance unit 20, and the jammed transfer paper P becomes free. You can get rid of this.

When a paper jam occurs in the double-sided tray 6 during the double-sided stacking or when a paper jam occurs during re-feeding, it is necessary to remove the transfer paper P from the double-sided tray 6. At this time, the rotating shaft 30
The second transport unit upper unit 30 is opened centering on a, and the jammed transfer paper P is removed.

FIG. 3 is an enlarged view of the first and second transport path portions, and shows a state where both the first and second transport guide plates are at the closed position.

After the upper transport unit 20 is opened, the first transport guide plate 11 constituting the first transport path 1 is pivoted to the center as shown in FIG.
The second conveyance path 2 is rotated counterclockwise around 11a.
Open the sheet exit part of.

A force is applied to the first transport guide plate 11 by a slide shaft 11c rotatably mounted about a rotation center 11b and a compression spring 11d mounted on the slide shaft 11c. As shown in FIG. 4, when the first transport guide plate 11 is opened, the force of the compression spring 11d acts in the opening direction, and the moment by the force of the spring 11d and the first transport around the fulcrum 11a. The moment due to the weight of the guide plate 11 is balanced, and the open position of the first guide plate 11 is determined at that position.

The first transport guide plate 11 has a lock portion 11 as an engagement portion.
e is provided.

As shown in FIG. 6, the slide shaft 11c is moved so that the position of the upper fulcrum 11b is moved by the rotation of the first transfer guide plate 11 and the axial movement is free. The position is held at the lower side by a member 11f rotatably supported by the side plate 101.

The second transport guide plate 12 is rotatable about a rotation center 12a, and is a rotation center 12b which is an example of a position holding unit.
A force is applied by a slide shaft 12c that is rotatably mounted around the shaft and a compression spring 12d mounted on the slide shaft 12c. The slide shaft 12c is held in position by a member 12f shown in FIG. 6, similarly to the slide shaft 11c.

The driven roller 12e of the second transport guide plate 12 is pressed against the drive roller 13 by a pressing member 12g, which is an example of a pressing unit. Bracket part 12g of pressure member 12g
A lock pin 1 is an engagement member as shown in FIG.
The position is determined by engaging the lock portion 11e in the closed position of the first transport guide plate 12 and the driven roller 12e is pressed by the pressing member 12g, and the driven roller 13e is mounted. And an appropriate pressing force is generated. The lock pin 12h is fixed to the bracket portion 12g-1 by caulking as shown in FIG. 7, but the roller 12h-1 is fitted so as to smoothly engage and disengage.

 FIG. 4 shows a state where the first transport guide plate 11 is opened.

When the first transport guide plate 11 is at the open position, the engagement between the lock portion 11e and the lock pin 12h is released, the second transport guide plate 12 is lowered, and the pressure between the drive roller 13 and the driven roller 12e is reduced. Depressurized. When the engagement is released, the second transport guide plate 12 moves the drive roller 13 and the driven roller 12e.
The pressure is applied between the slide shaft 12c and the compression spring 12d mounted on the slide shaft 12c so that the pressure is set at the position.

If the pressure between the driving and driven rollers is opened and the pressure is released,
The jammed sheet in the conveyance path 2 can be removed. In other words, by simply opening the first transport guide plate 11, a special pressure-reducing mechanism is provided and the pressure between both rollers is reduced without the need to operate the pressure-reducing mechanism, so that the jam can be removed by a simple operation.

FIG. 5 shows that after the first transport guide plate 11 is in the open position,
The figure shows a case where the second transport guide plate 12 is further pushed down while holding the bracket portion 12g-1 of the pressing member of the transport guide plate 12. In the present embodiment, the position holding means of the second conveyance guide plate 12 when the roller is not pressurized has an elastic structure having the slide shaft 12c and the compression spring 12d. The second as shown
The transport guide plate 12 can be lowered to widen the second transport path. As a result, even if a sheet remains inside, it can be easily taken out. When the hand is released from the bracket portion 12g-1 in the state of FIG. 5, the operation returns to the state of FIG. 4 automatically by the operation of the compression spring 12d. When the first transport guide plate 11 is set to the closed position, the state shown in FIG. 3 is obtained, and the lock portion 11e of the first transport guide plate 11 is engaged with the lock pin 12h of the second transport guide plate to perform positioning. .

Advantageous Effects of the Invention As described above, according to the present invention, the engagement of the driven roller pressurizing means of the second transport guide plate is released and the pressure of the driven roller can be released by simply opening the first transport guide plate. Thus, the operability in the jam processing is improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a sheet conveying device used in a copying machine showing an embodiment of the present invention, FIG. 2 is a diagram showing a state where the first conveying unit is opened, and FIG. FIGS. 4 and 5 are views showing the first transport guide plate opened, FIG. 6 is a cross-sectional view showing the slide shaft holder, and FIG. It is sectional drawing of a lock pin. DESCRIPTION OF SYMBOLS 1 ... 1st conveyance path 2 ... 2nd conveyance path 11 ... 1st conveyance guide plate 11e ... Lock part (engagement part) 12 ... 2nd conveyance guide plate 12c ... Slide shaft (position holding means) 12d compression spring (position holding means) 12e driven roller 12g pressure member (pressure means) 12h lock pin (engagement member) 13 drive roller

Claims (1)

(57) [Claims] An openable first transport guide plate which forms a first transport path for transporting a sheet; and a second transport path which is continuous with the first transport path, and which is pressed against a fixed driving roller. An openable and closable second transport guide plate having a driven roller mounted thereon, an engaging portion with the first transport guide plate, and pressurizing means for pressing the driven roller against the driving roller; An engaging member that engages with the engaging portion at the closed position of the first transport guide plate and sets the pressurizing unit to a pressing position; and when the engagement between the engaging portion and the engaging member is released, The second
Means for holding the conveyance guide plate at a predetermined position, wherein at the time of the disengagement, the pressurizing means is released and the driven roller is depressurized.