JP3287619B2 - Sheet transport path switching device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer path switching device for a branch provided in a sheet transfer path of an image forming apparatus such as an electrophotographic copying machine or a printer.

[0002]

2. Description of the Related Art In an image forming apparatus such as an electrophotographic copying machine or a printer, a switching claw 10 as shown in FIG. , B, and a gate system that switches the position of the switching claw 10 by a solenoid (not shown) and conveys the sheet P conveyed by the feed roller 3 on the upstream side of the branch to a selected conveyance path. Widely adopted. When the branching claw 10 is set to a position that closes the lower conveyance path B as shown by a solid line, the sheet is sent to the upper conveyance path A, and the branch claw 10 is moved to a position that closes the upper conveyance path A as shown by a broken line. In this case, the sheet P is sent to the lower conveyance path B.

However, in the transport path switching apparatus of this type, if the branch claw 10 is switched while the sheet is being transported to the branch portion, the sheet being transported is moved to the branch claw 1.
The sheet P is strongly pinched between the leading end of the sheet P and the guide plate, and the sheet P is jammed or damaged. Therefore, it is necessary to feed the sheet with a large sheet interval, which is not suitable for high-speed switching.

In view of the above-mentioned problem of the gate system using the branch claws, the present applicant has previously provided a switching roller 1 capable of rotating forward and reverse at a branch portion as shown in FIG. The leading edge of the sheet P conveyed from the sheet feed roller pair 3 is brought into contact with the peripheral surface of the switching roller 1 rotating in any direction, and the sheet is moved by the action force between the sheet leading edge and the switching roller 1. A transport path switching device that selectively guides to one transport path has been proposed.

In FIG. 8, when the switching roller 1 rotates counterclockwise as indicated by the solid line arrow, the sheet P whose leading end abuts on the sheet is guided to the transport path A as indicated by the solid line, and the switching roller 1 is rotated. In the case where the sheet P rotates clockwise as indicated by the dashed arrow, the sheet P whose leading end abuts on the sheet is guided to the transport path B as indicated by the dashed line.

Since the conveyance path is switched by switching the rotation direction of the switching roller, a switching operation can be performed regardless of whether or not a sheet exists in the branch portion, and high-speed switching can be performed regardless of the sheet interval. Can be.
Further, since there is no suction operation of the solenoid, no sudden sound is generated and a low-cost and highly reliable switching device can be realized.

By the way, the switching roller type sheet conveying path switching device proposed by the present applicant has
There is no specific description of the configuration of the switching roller, and it is considered that one long roller having the same diameter from end to end is simply assumed. Therefore, there is a disadvantage that the weight of the switching roller is increased, the material cost is increased, the inertia of the rotation is increased, and the response of the forward / reverse rotation switching is deteriorated.

Further, since the switching roller 1 is a single long cylindrical roller, a gap is provided between the end of the inner guide plate 4 forming the branch path and the outer peripheral surface of the switching roller 1 as shown in FIG. When the sheet P is fed to the switching roller 1 in a curled or broken state, the sheet P is not guided to a desired conveyance path,
There is a possibility that the sheet enters the space between the switching roller 1 and the guide plate 4 and is caught by the switching roller 1 to cause a jam.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-mentioned problems of the conventional sheet conveying path switching device, and has a roller for switching the sheet leading end even when the sheet is fed in a curled or broken state. It is an object of the present invention to provide a sheet conveyance path switching device that is smoothly conveyed to a desired path without being caught in a sheet.

[0010]

In order to solve the above-mentioned problems, the present invention has a switching roller rotatable in both forward and reverse directions at a branch portion of a sheet transport path, and is conveyed from an upstream side of the branch portion. In a sheet conveying path switching device for switching the sheet conveying path by an action force between the sheet leading end and the switching roller peripheral surface, the sheet leading end abuts on a switching roller rotating in any direction, the switching roller includes: Multiple roller parts on a shaft smaller than the outer diameter of the roller,
It is a split type roller that is provided in the skewers at intervals,
A guide plate on the switching roller side of the branch path is integrally connected, and a relief hole is formed in the guide plate corresponding to a roller portion of the switching roller, and the switching roller has a shaft outside the sheet conveying path. A part of the roller portion is disposed so as to protrude into the sheet conveying path from the relief hole.

[0011]

[0012]

According to the above arrangement, since the guide plate for guiding the sheet in the direction selected by the switching roller extends between the roller portions of the switching roller, the leading end of the sheet conveyed from the upstream side is provided. Even if it is curled,
Even if it is broken, it does not enter between the roller and the edge of the guide plate and is wound around the roller, so that jamming and breakage of the sheet do not occur.

[0013]

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings.

1, 2 and 3 are a side sectional view, a plan view and a perspective view, respectively, of an embodiment of the present invention. In these figures, members having the same functions as those of the previously proposed transport path switching device shown in FIG. 8 are denoted by the same reference numerals.

The switching roller 1 of the apparatus according to the present embodiment is shown in FIG.
As shown in FIG. 3, a plurality of roller portions 1b formed in a short width on a shaft 1a having a diameter smaller than the outer diameter of the roller are skewered at intervals to form a split roller.

Further, as shown in FIG.
And B, the guide plate 2 on the side of the switching roller 1 is provided extending in a groove between the roller portions 1b of the switching roller 1,
The guide plates 2 of the route A and the route B are integrally connected. That is, as shown in FIGS. 3 to 5, the guide plate 2 is provided with an escape hole 2 a corresponding to each of the roller portions 1 b,
The switching roller 1 is disposed such that the shaft 1a is outside the paths A and B, and the roller portion 1b projects partly from the relief hole 2a.

Therefore, as shown in FIG. 1 and FIG. 2, when the sheet P is conveyed from the feed roller 3 on the upstream side of the branching section, the sheet is changed to the leading end thereof according to the rotation direction of the switching roller 1. It is guided to the transport route A or B by the acting force with respect to the peripheral surface of 1, and is transported along that route. 1 and 4 show a state in which the switching roller 1 rotates counterclockwise to feed the sheet P to the conveyance path A, and FIG. 5 shows a state in which the switching roller 1 rotates clockwise and the sheet P is sent to the conveyance path B. Is shown.

Since the guide plate 2 extending from the switching roller 1 is provided so as to extend into the groove between the roller portions 1b as described above, the leading end of the sheet is prevented from being entangled in the switching roller, and the sheet can be smoothly transported as desired. You can be guided on the route.

By the way, both ends in the width direction of the front end of the sheet are:
Depending on the conditions at the time of sheet feeding or during conveyance, the sheet is particularly easily curled or broken. When the curled or broken sheet comes into contact with the switching roller, the sheet conveyance becomes unstable.

In the sheet conveying path switching device of the present invention,
The switching roller is a divided roller in which a plurality of roller portions are skewed at intervals, so that both ends in the width direction of the standard size sheet used in this apparatus are located between the roller portions of the switching roller. In addition, it is easy to determine the arrangement of the roller portions of the switching roller so that both end edges of the sheet are not too far from the nearest roller portion within the width of the sheet.

FIG. 6 is a diagram showing an embodiment of the switching roller 1 which meets this requirement. Sheets P1, P2 of different sizes
Both end portions in the width direction are roller portions 1b of the switching roller 1.
And the roller portions 1b are arranged such that both end edges do not move away from the outermost roller portion 1b within the width of the sheet. Therefore,
Even if both ends of the sheet are curled or broken, it is possible to stably switch the sheet conveying direction.

[0023]

As described above, according to the present invention, even if the leading end of the sheet is curled or broken, the sheet can be smoothly guided in the transport direction without being caught by the switching roller. Becomes

[Brief description of the drawings]

FIG. 1 is a side sectional view of an embodiment of a sheet conveyance path switching device according to the present invention.

FIG. 2 is a plan view thereof.

FIG. 3 is a perspective view thereof.

FIG. 4 is a perspective view illustrating a state in which a sheet is transported to an upper transport path by the apparatus.

FIG. 5 is a perspective view showing a state in which a sheet is conveyed to a lower conveyance path by the apparatus.

FIG. 6 is a plan view of another embodiment of the present invention.

FIG. 7 is a side sectional view of an example of a conventional sheet conveyance path switching device.

FIG. 8 is a side sectional view of another example of the conventional sheet conveying path switching device.

FIG. 9 is an explanatory diagram for explaining the problem.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Switching roller 1a Roller shaft 1b Roller part 2 Guide plate 3 Paper feed roller pair A Upper sheet conveyance path B Lower sheet conveyance path P Sheet

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Yasufumi Nakazato 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd. (56) References JP-A-61-86358 (JP, A) (58) ) Surveyed field (Int.Cl. ⁷ , DB name) B65H 29/60

Claims (2)

(57) [Claims] 1. A switching roller rotatable in both forward and reverse directions at a branch portion of a sheet conveying path, and a leading end of a sheet conveyed from an upstream side of the branch portion is brought into contact with a switching roller rotating in either direction. In the sheet transport path switching device that switches the sheet transport path by an action force between the sheet leading end and the switching roller peripheral surface, the switching roller includes a plurality of roller portions on a shaft thinner than the outer diameter of the roller.
It is a split type roller that is provided in the skewers at intervals,
A guide plate on the switching roller side of the branch path is integrally connected, and a relief hole is formed in the guide plate corresponding to a roller portion of the switching roller, and the switching roller has a shaft outside the sheet conveying path. Wherein a part of the roller portion is disposed so as to protrude from the relief hole into the sheet conveying path. 2. The sheet conveying path switching device according to claim 1, wherein the switching roller is provided at a position where the roller portion does not overlap both ends of the width of the sheet to be conveyed.