JPS6356140B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement in a sheet conveying device suitable for use, for example, in a facsimile machine to automatically convey documents.

[Technical background of the invention]

Conventionally, as this type of sheet conveying device, there are, for example, those shown in FIGS. 1 and 2. 1st
The figure is a front view thereof, and FIG. 2 is a sectional view taken along the line A-A in FIG. 1. In the figure, supply roller mechanism 1
is composed of a roller 11 narrower than the sheet 2 and a sorting piece 12 that presses against the circumferential surface of the roller 11, and is disposed at the center of the sheet 2 in the width direction. On the other hand, on the downstream side of the supply roller mechanism 1, a conveyance roller mechanism 4 is disposed. This conveyance roller mechanism 4 includes a plurality of rollers 41, 41 arranged at regular intervals in the width direction of the sheet,
It is composed of pressing members 42, 42 that contact the peripheral surfaces of these rollers 41, 41, respectively, and each of the rollers 41, 41 is rotated at a constant speed by a drive mechanism (not shown) via a shaft 43. ing. Here, the rotational speed of the rollers 41, 41 is such that the rotation speed of the rollers 41, 41 is such that the sheets 2 are sequentially fed one by one from the supply roller mechanism 1.
When a sheet is fed out, the distance between the trailing edge of the preceding sheet and the leading edge of the following sheet is widened, and this increases the number of sheets fed out, and in facsimile, the leading and trailing edges for the start and end of main scanning. In order to facilitate detection, the conveyance speed is set higher than the conveyance speed of the supply roller mechanism 1.

When the supply roller mechanism 1 and the conveyance roller mechanism 4 are each rotated, the sheets 2, 2, ... set on the sheet supply table 3 are first separated one by one by the supply roller mechanism 1, and then transferred to the conveyance roller mechanism 4. is conveyed to the downstream device at high speed by the conveyance roller mechanism 4.

[Problems with background technology]

However, in such conventional devices, the pressing members 42, 42 are generally positioned so that the contact positions 42' of the pressing members 42, 42 with respect to the respective rollers 41, 41 of the conveying roller mechanism 4 are equal to each other. In other words, the biting positions 42' of the sheet 2 in each of the rollers 41, 41 are all set equally with respect to the conveying direction C of the sheet 2.

Therefore, when a sheet whose leading end is cut diagonally is conveyed, or when the sheet 2 is fed out obliquely from the supply roller mechanism 1, the side edges of the sheet that protrude from the center part are exposed to the conveyance roller. The roller 41 located at the side (end) of the mechanism 4 will be caught first. In this way, if the side edges of the sheet 2 are bitten first, the conveyance roller mechanism 4 is faster than the supply roller mechanism 1, and the center portion of the sheet 2 is still being held by the supply roller mechanism 1. The clamping point is used as a fulcrum to rotate due to the difference in conveying speed between the roller mechanisms 1 and 4. When rotation occurs in this manner, the sheet 2 conveyed from the conveyance roller mechanism 4 is conveyed in a skewed state, or the degree of skew is increased compared to the state before the jamming. As a result, the conveyance stability of the sheet 2 decreases, and depending on the degree of skew, the sheet 2 may deviate from the normal path and cause a jam, or the sheet 2 may be damaged, which is undesirable. .

On the other hand, in order to reduce such problems, it has been considered to provide a conveyance roller only in the center, or to convey the sheet while being held between only the conveyance rollers located in the center. However, in such a configuration, after the trailing edge of the sheet is released from being pinched by the supply roller mechanism, the sheet is conveyed with only its center portion being pinched, so that the conveyance of the sheet is There was a problem that the direction and conveyance state tended to become unstable.

[Purpose of the invention]

The present invention prevents the sheet from being skewed and the increase in skewed feeding without destabilizing the conveyance state of the sheet after it is released from the supply roller mechanism, thereby providing a sheet conveying device with high conveyance stability. The purpose is to

[Summary of the invention]

In order to achieve the above-mentioned object, the present invention has provided that, among the plurality of sheet biting positions in the conveying roller mechanism, the biting position of the portion located on the conveying extension of the supply roller mechanism is the most in the sheet conveying direction. It is set so that it is on the upper side, so that among the sheets sent from the supply roller mechanism, the portion located on the extension of the gripping position by the supply roller mechanism is first bitten.

[Embodiments of the invention]

3 and 4 show a sheet conveying device according to an embodiment of the present invention, FIG. 3 is a front view thereof, and FIG. 4 is a sectional view taken along the line B--B in FIG. 3. In this figure, the same parts as in FIGS. 1 and 2 are given the same reference numerals and detailed explanations will be omitted.

In the apparatus of this embodiment, the configuration is different from that shown in FIGS. 1 and 2 above. Among the rollers 41, 41 of the conveyance roller mechanism 4, the roller 11 of the supply roller mechanism 1 has an extension in the conveyance direction. The roller located above, that is, the roller 4 located in the center in the figure
Contact position 42 of the pressing member 42a that contacts 1a
a' of the sheet 2 from the abutment position 42' of the pressing members 42, 42 against the rollers 41, 41 on both sides.
This point is set to be on the upstream side in the conveyance direction. That is, in the figure, the roller 41a is
The contact position 42a' of the pressing member 42a against the other rollers 41, 41 is
It is positioned upstream in the sheet conveyance direction C from the contact position 42' of the sheet.

Because of this configuration, even if the sheet 2 is fed with a slight skew, or even if a sheet whose leading end is cut diagonally is fed, the degree of skew will be within a certain range (i.e. absorbed by x). (within the range that is possible), the center of the sheet 2 is first moved by the roller 41a.
and its pressing member 42a, and then both side portions are caught between each roller 41 and its pressing member 42a. Therefore, no rotational force is generated in the sheet 2 during the biting, and as a result, the sheet 2 is conveyed downstream without increasing the degree of skew or without causing skew.

As described above, in the apparatus of this embodiment, among the rollers 41, 41 of the conveyance roller mechanism 4, the roller located on the extension of the conveyance path of the supply roller mechanism 1, that is, the central roller 41a, has a biting position 42a'. , the biting position 42' of each roller 41, 41 on both sides
Since it is set on the upstream side, no rotational force is generated when the sheet 2 is caught, and the sheet 2 can be conveyed extremely stably without being skewed. Therefore, problems such as jamming or damage to the sheet can be reduced.

In addition, since each roller 41 of the conveyance roller mechanism is designed to convey the sheet 2 while sandwiching it with equal pressure, the rear end of the sheet 2 is transferred to the supply roller mechanism 1.
After the sheet 2 is released from the clamping by the rollers 41 and the pressing members 42, 42a, the sheet 2 is conveyed while being clamped at a plurality of locations by the rollers 41 and the pressing members 42, 42a. Therefore, the sheet can be transported more stably than, for example, when the sheet is held and transported only by the central roller and the pressing member 42a.

Note that the present invention is not limited to the above embodiments. For example, in the above embodiment, the rollers 41,
Contact position 4 of the pressing members 42, 42 with respect to 41
2' and the contact position 42a' of the pressing member 42a with respect to the roller 41a, a positional shift was provided at the biting position.
If a pinch roller is used instead, change the contact position of this pinch roller, or leave the contact position of the pinch roller as it is and bring a pressing member into contact with the circumferential surface of the roller on the upstream side. Accordingly, a positional shift may be provided at the biting position. In addition, the structure, arrangement positional relationship, etc. of the conveyance roller mechanism and the supply roller mechanism can be modified in various ways without departing from the gist of the present invention.

〔Effect of the invention〕

As described in detail above, the present invention sets the sheet biting position in the conveyance roller mechanism so that the portion located on the extension of the conveyance path of the supply roller mechanism is the most upstream side in the sheet conveyance direction. It is something.

Therefore, according to the present invention, it is possible to prevent the skewed feeding of the sheet and the increase in skewed feeding without destabilizing the conveyance state of the sheet after it is released from the supply roller mechanism, thereby stabilizing the conveyance. Therefore, it is possible to provide a sheet conveying device with high performance.

[Brief explanation of the drawing]

1 and 2 show a schematic configuration of a conventional sheet conveying device, in which FIG. 1 is a front view thereof, FIG. 2 is a sectional view taken along the line A-A in FIG. 1, and FIGS. FIG. 4 shows a schematic configuration of a sheet conveying device according to an embodiment of the present invention, FIG. 3 is a front view thereof, and FIG. 4 is a sectional view taken along the line B--B in FIG. 3. 1... Supply roller mechanism, 2... Sheet, 11...
...Roller, 12... Sorting piece, 4... Conveyance roller mechanism, 41, 41a... Roller, 42, 42a...
Pressing member, 42', 42a'... contact position (biting position), 43... shaft.

Claims (1)

[Claims] 1 A supply roller mechanism having a sorting section and having a width narrower than the sheet separates and feeds the sheets one by one, and the sheets are then transferred to a plurality of the sheets by a conveyance roller mechanism having a higher conveyance speed than the supply roller mechanism. In a sheet conveyance device that conveys a sheet to the downstream side by pinching a portion, a portion located on an extension of the conveyance path of the supply roller mechanism among the biting positions of the sheet in the conveyance roller mechanism is the most upstream portion in the conveyance direction of the sheet. A sheet conveying device characterized in that the sheet conveying device is set so as to be on the side.