JPS61282241A - Sheet carrying apparatus - Google Patents

Abstract

PURPOSE:To improve the carrying stability while to reduce the carrying noise, in U-turn carrying apparatus for copy machine, by employing crape finish on the inside face of U-turn member for passing a sheet. CONSTITUTION:A rib (a) is provided on the surface of an inside guide 14b of U-turn guide 14 while crape finish (b) is employed on the entire surface of the inside guide 14b including the rib (a). With such structure, the surfaces of the inside guide 14b and the sheet to be carried will point contact to retard the adsorbing phenomena between the surface of U-turn guide 14 and the sheet resulting in stable carrying.

Description

Detailed Description of the Invention [Scope of Industrial Application] The present invention relates to a sheet conveying device for a facsimile, a copying machine, a printer, etc., and particularly to a sheet conveying device in which the sheet is conveyed in a U-turn by a curved guide. It is related to the device.

[Problems to be solved by conventional technology and invention]

2. Description of the Related Art Conventionally, there has been known a sheet conveyance device that includes a path for U-turning a sheet in a conveyance path for conveying the sheet, and includes conveyance rollers that apply conveyance force to the beginning and end of this path.

However, in such a mechanism, the document always tends to follow the U-turn guide, so if the document has a smooth surface such as lightweight art paper, coated paper, art paper, etc., the document surface and the U-turn guide The surface attracts static electricity, etc., and creates a resistance stronger than the document ejecting force due to the urging force of the paper ejecting roller, making it difficult to load the original onto the paper ejecting tray. On the other hand, since the suction force between the surface of the document and the surface of the U-turn guide is weaker than the document conveyance force due to the urging force of the conveyance rollers, the document may become clogged near the U-turn guide, and in some cases, the document may be bent or jammed. In addition, an abnormal noise may be generated due to the U-turn guide rubbing against a document having a smooth surface such as art paper.

[Purpose of the invention]

The present invention provides a sheet conveying device that can solve the problems of the conventional method described above, increase the stability of sheet conveyance, and reduce conveyance noise when the sheet passes through a U-turn guide. be.

〔Example〕

FIG. 1 shows an example in which an embodiment of the present invention is applied to a sheet document reading device in which a U-turn mechanism is provided in a paper conveyance path.

In the figure, l is the main body of the apparatus, 2 is a sheet document, 7 is a separation belt that separates the documents, 3 is a separation pulley that rotates the separation belt 7, 5 is a separation idler, 8 is a conveyance belt that conveys the document, and 4 is a conveyance belt. Conveyance pulley that rotates the belt, 6
9 is a conveyance idler; 9 is a conveyance roller (1) rotated by a motor (not shown); 10 is a conveyance roller (1) which is biased against the conveyance roller (1) by a biasing member such as a spring (not shown); 1 is a document guide plate that guides the document; 12 is a conveyance roller (2) rotated by a motor (not shown); and 13 is a conveyance roller (2) urged by a biasing member such as a spring (not shown). ),
14aI+14b makes a U-turn on the scanned original
It is a turn guide. Note that 14a is an outer guide, 14
b is the inner guide. Furthermore, 15 is a paper ejection roller rotated by a motor (not shown), 16 is a paper ejection roller that is urged against the paper ejection roller 15 by a biasing member such as a spring (not shown), and 17 is a paper ejection roller on which ejected documents are stacked. A paper tray 18 is a reading unit that reads a document.

Now, the sheet conveyance device shown in FIG. 1 includes a member that constitutes a document conveyance path that starts after the reading unit and makes a U-turn.The sheet conveyance device shown in FIG. Pair of rollers and conveying rollers 12.1
This is an example of an optical reading device equipped with 3, 15 and 16.

Here, in FIG. 1, by setting the original 2 to be read and pressing the start switch, etc., not shown,
The document 2 is caught between the conveyor belt 8 and the separation belt 7 by a pickup roller (not shown). In addition, a motor (not shown) is connected to a conveyor pulley 4, a separation pulley 3,
Conveyance roller (1)9. The conveyance roller (2) 12 and the paper discharge roller 15 rotate in the direction of the arrow shown in FIG. 1 for the friction coefficient of the conveyor belt 8 with the original, the friction coefficient J42 of the separation belt 7 with the original, and the friction coefficient 1 between the original. What kind of relationship is this? ＞
Therefore, among the multiple documents 2 that have entered between the conveyor belt 8 and the separation belt 7, only the document that is in contact with the conveyor belt 8, that is, the one document placed on the top, is transferred to the conveyor belt 8. conveyed by conveying roller (1) 9 and conveying roller (1)
) until it reaches position 10. Since the conveying roller (1) 10 is pressed against the conveying roller (1) 9 by a spring or the like (not shown), the rotation of the conveying roller (1) 9 applies a conveying force to the document, and the document is advanced along the document guide 11 and read. unit 18
The original is read.

The read original further advances along the original guide and reaches the position of the transport roller (2) 12 and the transport roller (2) 13. Since the conveying roller (2) 13 is pressed against the conveying roller (2) 12 by a spring or the like (not shown), the rotation of the conveying roller (2) 12 applies a conveying force to the document, and the document is moved along the U-turn guide 14. The document is U-turned, and paper ejection roller 1
5 and paper ejection roller 16. Since the paper ejection roller 16 is pressed against the paper ejection roller 15 by a spring or the like (not shown), the rotation of the paper ejection roller 15 applies a conveyance force to the document, and the document is ejected onto the paper ejection tray 17.

Here, since the circumferential speed of the paper ejection roller 15 is slightly faster than the circumferential speed of the transport roller 12 (as shown in FIG. 3), the document spacing is 2, and the document 2 is placed on the ejection roller 1 as shown in Fig. 2.
Even if the document shifts slightly due to the buckling of the leading edge of the document when it is caught between the transport rollers (2) and the paper ejection rollers 16 and overlaps the next document, the previous document will be moved between the transport rollers (2) 12 and the transport rollers (2).
13, and when the conveying force is applied by the paper ejection roller 15 and the paper ejection roller 16, the next original is 1
Since the wI feed roller (2) 12 and the conveyance roller (2) 13 are engaged with each other, the paper ejection roller 15 and the conveyance roller (2) 12 are engaged with each other.
Due to the speed difference, a speed difference occurs between the two documents, and the overlapping documents also become separated. The biasing force of the paper ejection roller 16 is applied in order to prevent paper ejection roller marks from being left on the document, and to prevent the document from meshing with the transport roller (2) 12 and the transport roller (2) 13, and further between the paper ejection roller 15 and the paper ejection roller 16. When they are engaged with each other, the original is transported only at the circumferential speed of the transport roller (2) 12, and the paper ejection rollers 15 and 16 are extremely weak so that the original slips. Furthermore, when the original is separated from the nip between the transport rollers (2) 12 and transport rollers (2) 13 and is transported only by the paper ejection rollers 15 and 16, the original is separated from the paper ejection rollers 15 and Even if there is some slippage during the engagement of the rollers 16, the circumferential speed of the ejection roller 15 is slightly faster than the circumferential speed of the transport rollers (2) 13, so the documents in front and behind will not overlap.
Since the document passes along the turn guide 14, the document conveyance system is also stabilized. Note that in this embodiment, as described above, the roller 15
Since the circumferential speed of the roller 12 is faster than that of the roller 12, the document is often pulled and conveyed by the dust, and the document is often conveyed in contact with the surface of the inner guide 14b. Therefore, in this embodiment,
A rib a is provided on the surface of the inner guide 14b of the U-turn guide 14.
At the same time, the entire surface of the inner guide 14b, including the ribs a, is made of a satin finish (with a grain finish in the case of a mold).
) 12, even if an original with a smooth surface such as art paper comes into contact with the inner guide 14b, it will contact the inner guide 14b not on one side but at a point, so the original will not stick to the surface of the U Tartsuga 4114. The frictional force between the U-turn guide 14b and the document with a smooth surface is reduced, so the document is ejected to the output tray without hesitation, and at the same time, the friction between the document with the smooth surface and the U-turn guide 14 is reduced. There is no abnormal noise due to rubbing (FIG. 4(a) shows a plan view of the inner surface of the guide 14b, and FIG. 4(b) shows a side view thereof).

In the embodiment shown in Fig. 1, the seat is U-turned from bottom to top, but even if the seat is U-turned from top to bottom, the seat can also be U-turned from left to right or right to left. A similar effect can be obtained with a turning mechanism. Note that when passing a sheet with a smooth surface such as stiff art paper, the peripheral speed of the conveying roller at the end of the U-turn guide 14 should be slower than the peripheral speed of the conveying roller at the beginning of the U-turn guide 14. Then, the outer guide 1 of the U-turn guide 14
Sometimes the original is placed along 4a. In that case, if the surface of the outer guide 14a of the U-turn guide 14 is made matte or/and provided with ribs, the U-turn guide 14
There is no adhesion between the outer guide 14a and the surface of the document.
Guide the sheet paper in a U-turn without hesitation! It is possible to pass around 4.

〔Effect of the invention〕

As explained above, according to the present invention, an apparatus for conveying a sheet of paper is provided with a member for U-turning the paper in the conveyance path, and the U-turn section Zto/711 Todoroki et al. → hi L1 nJ, 11 noti punishment = 11-bite jcl-
1#I: 1-hi, 艮;:=1--N.

In a sheet conveying device equipped with a conveying means, the inner sheet passing surface of the U-turn member has a matte finish to improve sheet conveyance stability when the sheet passes through the U-turn member. It has the effect of reducing the sound of the guide and sheet passing through.

[Brief explanation of the drawing]

FIG. 1 shows that an original to be read is conveyed from the paper feed side by a curved original guide to which an embodiment of the present invention is applied.
A cross-sectional view of an optical reading device for a sheet document that is read and then makes a U-turn toward the paper feed side again. FIG. 2 is a side view showing the state immediately before the document is bitten by the paper ejection roller and the paper ejection roller. A side view showing the state near the U-turn guide of the document when the circumferential speed of the conveyance roller is slower than the circumferential speed of the paper ejection roller, FIG. 4(a)
is a plan view of the inner surface of the guide, and FIG. 4(b) is a side view thereof. In the figure, l is the apparatus body, 2 is the document, 3 is the separation pulley, 4 is the conveyance pulley, 5 is the separation idler, 6 is the conveyance idler, 7 is the separation belt, 8 is the conveyance belt, 9 is the conveyance roller (1), to is the transport roller (1), 11 is the document guide plate, 12 is the transport roller (2)', 13 is the transport roller (
2), 14 is a U-turn guide, 15 is a paper ejection roller, 16
is a paper output roller, 17 is a paper output tray, 18 is a reading unit,
a is lipstick, b is satin finish.

Claims (3)

[Claims] (1) A sheet conveying device for conveying a sheet, comprising a member for U-turning the sheet in its conveying path, and a sheet passing surface inside the U-turning member having a satin finish. . (2) A conveyance roller is provided near the beginning of the U-turn member, and the circumferential speed of the conveyance roller is slower than the circumferential speed of the conveyance roller provided near the end of the U-turn member. The sheet conveying device described. (3) The sheet conveying device according to claim (1), in which the urging force of the conveying rollers provided near the end of the U-turn member is extremely weak.