JPH0420443A - Sheet carrier - Google Patents

Abstract

PURPOSE:To smooth carrying papers by supporting follower rollers of a carrier roller pair with an integrated retaining member, and providing a pressing member for pressing the following the following roller to the carrier roller pair. CONSTITUTION:At both ends of roller holder 10, follower rollers 2a, 2b facing a carrier roller pair are retained to rotate freely, and a central shaft 11 formed almost at the center between these two follower rollers are supported in a long hole 3c formed on a wall surface of ribbed face 3b of a guide door. The holder 10 is pressed under a specified force in the direction of carrier roller pair by means of push springs 12a, 12b at all times, and a guide face 10a is formed by one part of the roller holder 10, thereby constituting one part of a carrying passage together with the guide door.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to sheet conveyance, in particular, to a sheet material conveyance device in an image forming apparatus such as a copying machine.

[Prior Art] Conventionally, in image forming apparatuses such as copying machines, multiple sheet trays (cassettes) are used to accommodate various sheet sizes.
It is configured so that it can be pre-equipped with the main unit or added as an option.

For this reason, as shown in Fig. 5, there is a sheet conveyance bus configuration in which multiple sheets (rays) are placed one on top of the other and the sheets fed from each sheet tray are sequentially merged into conveyance paths (A, B). This allows multi-stage sheet trays to be created in a space-saving manner.The guide section on the outside of the device is usually configured to be openable and closable, making it possible to dispose of sheets that have accumulated due to jams, etc.

This conveyance bus is composed of conveyance rollers 4 for conveying the sheet 1-, and a guide member for guiding the sheet between the pair of conveyance rollers.

FIG. 6 is a detailed view of the conveyance path section A.

Drive rollers Ia and lb are supported by bearings on the side plates of the main body (not shown), and repeat rotation and stop at predetermined timings. Reference numeral 3 denotes a guide door, which has a plurality of ribs to form a guide for sheet conveyance, and is configured to be able to open and close around a rotating shaft 3a to clear paper jams caused by jams in this conveyance path section. . The driven roller 2a2b has its rotating shaft supported by a U groove formed in the rib of the guide surface 3, and a predetermined pressure is applied to the drive roller by a leaf spring 4 (4a, 4b) fixed to the guide surface 3. It is being pressed against.

Paper feeding rollers 5a and 5b feed the sheets S from the cassettes 6a and 6b.

7a and 7b are guide plates, 8a and 8b are guide plotters, and the sheets fed from the cassette are transferred to a pair of transport rollers (Ib, 2b, la) of the transport bus section A.

This leads to 2a).

[Problems to be Solved by the Invention] However, in the conventional example, when there is a variation in the condition of the guide surface or deformation such as warping of the guide door itself, the driven rollers (2a, 2a, 2b) is always kept in a suppressed state against the drive rollers (la, lb), but the guide surface of the rib shifts from the predetermined position, resulting in a change in the shape of the transport bus, resulting in the following drawbacks: was there.

(1) As shown in FIG. 8, if the driven roller 2a protrudes excessively from the rib surface of the guide surface, there is a risk of interfering with the conveyance of the sheet S.

(ii) As shown in FIG. 9, when the guide surface is tilted in the front-rear direction (perpendicular to the page),
There is a possibility that the route to the seat will be different. When the oscillating paths are different, the pair of conveying rollers (2a,
There will be a difference in the arrival time of the leading edge of the sheet at point la), resulting in skew feeding. A similar effect can be considered when the paper is transported from the direction (■) in the figure.

In particular, the problem mentioned above is that the sheets fed from the sheet tray are bent significantly when they merge into the transport bus, so changes in the shape of the transport bus at this merging point have a large effect on the stability of Sea 1 transport. are doing.

[Means for Solving the Problems (and Effects)] According to the present invention, by holding the driven rollers of adjacent conveying rollers with an integrated boulder, a plurality of sheets [・sheets fed from a tray The shape of the transport bus where the sheets merge is always kept in a predetermined state, thereby realizing stable sheet transport.

[Embodiment] The present invention will be explained below based on an embodiment shown in the drawings.

Embodiments of the present invention are shown in FIGS. 1 to 3.

10 is the roller holder, 11 is the center axis of the roller bolter, 1
2 is a push spring. The roller holder 10 has a
Driven rollers 2a, 2b relative to conveyance rollers Ia, lb
The center shaft 11 formed approximately at the center of these two driven rollers is supported by the elongated hole 3c formed in the wall surface of the rib surface 3b of the door, so that the arrow shown in the figure It is held movable in both directions. Roughly, the roller holder IO is always pressed against the transport roller with a predetermined force by push springs 12a and 12b.

Further, the roller holder 10 has a guide surface 10a in a part thereof.
It forms a part of the transport bus together with the guide surface (Fig. 2).

As shown in FIG. 3, the roller holder 10 is always driven by the driven roller 2a by the push spring 12.

2b is brought into contact with the conveyance rollers la and lb, and the corobolder 10 itself is also securely fixed in position by the two contact positions with the conveyance rollers and the center shaft 11. Thereby, the guide surface 10a of the roller holder is always held at an optimal position with respect to the kite board 7 and the guy 1-block 8, regardless of the attachment state of the guide surface 3.

As explained above, according to the embodiment of the present invention, by arranging the roller holder that holds two driven rollers and also forms part of the conveyance chime 1 across the conveyance junction from the sheet tray, the following can be achieved. There is an effect like this.

(i) An optimal transport bus shape can always be reliably formed based on the transport rollers.

(11) As a result, reliable conveyance performance can be achieved even in unstable portions of sheet conveyance, such as the merging point of sheet conveyance.

(iii) The above performance can be achieved with a roller holder, which is an extremely simple configuration that does not take up much space.

[Other Embodiments] FIG. 4 shows a second embodiment. In this example,
The roller holder 100 inside the guide screen 103 supports four driven rollers 2. Compared to the first embodiment, the number of Bekoro holders is reduced and the structure is further simplified.

Note that the present invention is not limited to the configuration of nails shown in the above two embodiments, and the optimal shape of the roller holder is selected depending on the arrangement of the pair of conveyance rollers and the shape of the conveyance path. .

Therefore, although a vertical conveyance path is shown in the above embodiment, the same applies to a horizontal or diagonal conveyance path, and is not limited to a straight conveyance path. Further, the merging portion is not limited to one location either.

Furthermore, the suppressing member of the driven roller is not limited to a structure in which it is pressed into contact with the roller holder, but even in a structure in which it is directly pressed against the driven roller, the relationship between the driven roller and the roller holder is the same as in the above embodiment. If so, you can get the same effect.

[Effects of the Invention] Since the sheet conveying device according to the present invention has the above-described configuration, it has the effect that sheets can be conveyed smoothly.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a part of the main part of the sheet conveyance/feeding lid embodying the present invention, Fig. 2 is a perspective view showing the entire main part, and Fig. 3 is a sectional view of the sheet transport device. , FIG. 4 is a perspective view showing a second embodiment of the present invention, FIG. 5 is a sectional view of a conventional copying apparatus, and FIGS. 6 to 9 are sectional views showing the movement of sheets in the conveyance path in FIG. 1... Drive roller 2... Followed roller 3... Guide door lO... Roller holder

Claims (1)

[Claims] In a sheet material conveying device comprising a plurality of conveyance roller pairs and a guide member, the driven rollers of the conveyance roller pairs are supported by an integral holding member, and a pressure force is applied to press the driven rollers against the conveyance rollers. A sheet conveyance device comprising: a member, the holding member forming a sheet conveyance guide member between the pair of conveyance rollers.