JPH0445041A - Paper matching device for image former - Google Patents

Abstract

PURPOSE:To make a sheet of paper feedable askew in a natural state by forming a guide rib, guiding both sides in the cross direction of the paper, at the upstream side of a paper matching part with a skew feed roller, so as to make a conveying distance at the side guide side shorter but the other side longer, respectively. CONSTITUTION:Each of ribs 12-14 is installed in a curved guide plate 11, and the rib 14 at a position nearer to a side guide 2 is made larger in protrusion height and better in circular arc that of the rib 14 at a distant position. Accordingly, length of a guide surface to a sheet of paper to be set up by these ribs 12-14, namely, a travel length becomes larger in a side of the rib 12, whereby the paper is moved askew in a direction where it separates from a reference line. Then, a paper square part is fed askew in the reverse direction with a skew feed roller 3 at regular intervals from the side guide 2, and it is fed out as pressing the side to the side guide 2. Therefore, skew feeding can be done in a natural state without giving an unnatural action to the paper.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a paper aligning device in an image forming apparatus such as an electronic copying machine or a printer. The present invention relates to a device that allows a sheet aligning device to easily perform an aligning action by a diagonal feed row by moving the corner portion of the leading end away from a guide means.

(Prior Art) In image forming apparatuses that use cut paper, such as electronic copying machines and printers, the cut paper sent out from a paper storage device such as a paper tray is placed so that the side of the paper is aligned with the reference line of the paper conveyance path. The paper is conveyed in a parallel state, and is positioned by a paper aligning device disposed immediately in front of the image transfer section, and then fed into the image transfer section. In the following explanation, the terms "side of the paper" and "corner" are
This term is used to refer to the surface of the paper on the reference line side and the corner of the leading edge of the paper on the reference line side.

However, depending on the state of friction between the roller device disposed in the paper transport path, the guide plate, etc. forming the paper transport path, and the paper, the side surface of the paper may not be transported along the reference line.

Therefore, in general image forming apparatuses, a paper alignment device consisting of a diagonal feed roller and a side guide is arranged immediately before the image transfer section, and the paper alignment device aligns the side of the paper along the reference line. A means of positioning is used.

However, if the paper is conveyed through the paper conveyance path with its sides protruding outward from the side guides,
The corner of the paper hits the side guide, causing problems such as the paper being rotated or the corner being bent.

Therefore, in order to prevent the above-mentioned inconvenience from occurring, in conventional image forming apparatuses, a means for separating the paper from the side guides is arranged in front of the paper aligning device, so that the side of the paper is moved away from the side guide. A method is used to keep the distance from the reference line.

The above-mentioned paper aligning device is, for example, disclosed in Japanese Patent Application Laid-Open No. 1986-
A device configured as shown in Japanese Patent No. 109344 and the like is used. The conventional sheet aligning device is constructed as shown in FIG. 5, in which the sheet aligning section 1 includes a side guide 2 disposed on the side of the sheet conveying path, and diagonal feed rollers 3.3. , and a Taber roller 4.

In the paper alignment device, the paper P sent from the paper feeder is diagonally fed by the taber roller 4 so that the side surface of the paper is separated from the side guide 2, and the paper P is fed diagonally by the taber roller 4.
Set the state shown in 1.

After that, the diagonal feed roller 3.3 performs diagonal feeding in a direction opposite to the feeding direction by the Taber roller,
The paper is conveyed from P2 to the state indicated by P3. Then, the sheet is positioned so that the side surface of the sheet is pressed against the side guide, and the sheet is conveyed toward the image transfer section.

Note that, in addition to the paper sent out from the paper storage device, the paper alignment device configured as described above also reverses the single-sided copied paper on which an image has been recorded on one side, and then sends it again toward the image transfer unit. This is a technical means that is also applied to devices that make double-sided copies.

(Problems to be Solved by the Invention) However, in the conventional paper aligning device as described above, the action of separating the paper from the side guide by the Taber roller continues until the paper passes through the Taber roller. However, there is a problem in that the degree of skew feeding varies depending on the paper size.

That is, as shown in FIG. 6, when the paper is A4 size and B4 size, the distance that the corner of the paper is separated from the side guide is greatly different as shown by the distances a and b. , a problem arises in that the stability of the operation of the paper alignment device decreases.

In addition, in the above-mentioned state, in order to feed the paper diagonally toward the side guide using the diagonal feed roller placed just before the paper alignment section, and position the paper by pressing the side of the paper against the side guide, The larger the size, the larger the distance required for paper alignment, which has disadvantages.

In addition to the above-mentioned paper movement distance problem, when separating the corners of the paper in response to the side guides, there is a problem with the taber roller and diagonal feed, and when the paper is located between the rollers, both rollers Since the nip pressure is set to be strong, stress may be applied to the paper, resulting in defects such as wrinkles on the paper.

(Object of the Invention) The present invention solves the above-mentioned drawbacks of the conventional paper alignment device, and aims to keep the corners of the paper at a distance of 111 points from the reference line while the paper is being conveyed through the paper conveyance path. It is an object of the present invention to provide a device in which the distance for positioning the paper can be shortened without using a taber roller by feeding the paper into a paper aligning device.

(Means and effects for solving the problems) The present invention has the following features:
A guide means as a reference line for feeding the paper is arranged on the side of the paper conveyance path, a roller is arranged to feed the paper obliquely toward the guide means, and the side of the paper on the reference line side is aligned with the guide means. The present invention relates to a sheet conveyor provided with alignment means for positioning one side of the sheet while sliding the sheet.

In the first aspect of the present invention, in order to diagonally feed the paper in a direction away from the reference line, a transport distance for guiding both sides of the paper in the width direction is set in the upstream paper transport path of the alignment device. Means is provided for making the guide means shorter and the other side longer.

By configuring as described above, the corners of the paper can be tilted from the reference line toward the inside of the paper transport path while the paper is being transported between the paper feed section and the paper alignment device. Since the conveyance function is performed, it is not necessary to provide a conventional means such as a taber roller, and the structure of the paper alignment section can be simplified.

Further, since the paper being conveyed through the paper conveyance path can be fed diagonally in a natural manner, damage to the paper can be prevented.

By configuring as described above, it is possible to shorten the distance for paper alignment in the paper alignment section, and it is possible to configure the paper conveyance device of the uniformity forming apparatus including the paper conveyance path to be compact. Become.

Further, in the second aspect of the present invention, the means for diagonally feeding the paper in a direction away from the reference line is provided by disposing a slip roller approximately in the center of the paper conveyance path on the upstream side of the paper alignment device, and An O-ra member is provided on each of the guide means side and the other side on the Fi side of the slip roller, and the guide means side roller member is arranged upstream of the roller member on the other side.

Then, due to the interaction between the slip roller and the downstream roller member, the corner of the paper is diagonally fed from the reference line toward the inside of the paper conveyance path, and then the diagonal feed roller device of the paper alignment device feeds the paper diagonally. It is possible to perform positioning along the reference line.

As described above, when the paper diagonal feeding means is composed of a slip roller and a roller member, the nip position with respect to the paper between the slip roller and the upstream roller member is different in both the width direction and the feeding direction. Therefore, due to the mutual action of the rollers, an effect of diagonally feeding the paper is exerted. Therefore, unlike the case of the Taber roller, unnecessary diagonal feeding force is not applied to the paper that is moved in the direction away from the reference line.

Even in this case, the distance between the corners of the paper and the side guides is maintained constant regardless of the paper size, and the subsequent alignment action in the paper alignment device can be performed satisfactorily.

(Example) The configuration of a paper alignment device of an image forming apparatus of the present invention will be described according to an illustrated example.

In the first aspect of the present invention shown in FIGS. 1 and 1a, the configuration of a paper conveyance path provided between a paper feed section and a paper alignment section 1 is shown.

In the embodiment described above, the diagonal feeding section 1 is provided in the middle of the paper conveyance path.
0, and ribs 12 to 14 having different lengths and curvatures are attached to the inside of the curved surface of the curved guide plate 11 in the diagonal feeding section, and the paper is guided by the ribs.

Further, a side guide 2 for setting a reference line of the paper and a diagonal feed roller 3.3 are disposed in a paper alignment section W1 disposed downstream of the diagonal feed section 10. As in the case of the conventional device, the paper alignment device uses a diagonal feed roller to diagonally feed the paper toward the side guide 2, and positions the paper with the side surface of the paper in contact with the side guide 2. It functions to feed the paper toward an image recording section located downstream of the paper alignment device.

In the diagonal feeding section 10, the ribs 12 to 14 provided on the curved guide plate 11 are configured to have different protruding heights from the inner surface of the curved guide plate 11 and different lengths with respect to the paper conveyance direction, as shown in the figure. ing.

That is, the rib 12 disposed at the farthest position from the side guide 2 provided in the paper alignment device is configured to have a low height and be short. On the other hand, the ribs 14 disposed near the side guide have a large protrusion height from the curved guide plate, and are formed into long arcs for guiding the paper. In addition, the rib 13 in the middle part
is constructed with a height and length intermediate between the two.

Therefore, in the length of the guide surface for the paper set by the ribs 12 to 14, the length Ll on the side of the rib 12 (farthest from the reference line) and the length Ll on the side of the rib 14 (position nearer to the reference line) The relationship with the length L3 is Ll>13, and the paper is moved obliquely in a direction away from the reference line.

In the diagonal feeding section 10, in order to press the paper against the ribs arranged on the curved guide plate 11, a paper pressing member 15 made of a plastic film or the like is arranged as shown in FIG. 1a. ing. In the illustrated example, the paper pressing member 15 uses a sheet-like member with a relatively low coefficient of friction, and directs the paper toward the ribs when the paper is moved from top to bottom in the diagonal feeding section. It is configured so that it can be pressed with a constant force.

When the paper passes through the diagonal feeding section 10, the paper is pressed against the surfaces of the ribs 12 to 14 having different lengths and heights by the paper presser member 15, and the movement distance of the paper is different on the left and right sides. Use this to feed paper diagonally.

Therefore, in the diagonal feeding unit of the present invention, when the paper passes through the diagonal feeding unit, diagonal feeding is performed so that the corners of the paper are separated from the reference line, and when the paper is fed into the paper alignment device 1. Then, the corner of the paper is separated from the side guide 2 by a certain distance.

Then, in the device 1 constituted by the side guide 2 and the diagonal feed roller 3.3, the paper is transferred to the side guide 2.
The paper is fed diagonally in the opposite direction to the diagonal feed using the ribs, and the side of the paper is pressed against the side guide while being conveyed, and the paper is sent along the reference line toward the downstream recording section. I can do it.

FIGS. 2 and 3 show the structure of an image forming apparatus including the diagonal feeding section, a paper aligning device, and devices before and after the paper conveyance path. In the example of the image forming apparatus shown in FIG. 2, a paper feeding device consisting of a paper tray 5 and a paper feeding roller 6 is arranged at the top of the apparatus, and the paper is fed through a downwardly curved diagonal feeding section 10. An alignment device 1 is arranged, and an image reading device transfer section is arranged downstream of the paper alignment device N1.

In the example of the image forming apparatus, the diagonal feed roller 3.3 provided in the sheet alignment device 1 is as shown in FIG.
Although it is possible to configure the roller to be pressed onto the guide plate, it is also possible to configure it as a type of device called a cross roller.

Further, a registration gate 7 is provided downstream of the paper alignment device 1.
and a registration roller 8 are arranged, and the gate 7 and the registration roller 8 are arranged.
By doing this, the leading edge of the paper is positioned, and the paper is sent out in synchronization with the toner image formed on the photosensitive drum 9, so that the image is transferred.

Around the photoreceptor drum 9, a means for forming an image using an electrophotographic process is arranged as in a general electronic copying machine, and the image forming apparatus is configured to be an electronic copying machine or a printer. It is possible to configure any device, such as configuring it as .

In the image forming apparatus configured as described above, when the paper fed from the paper tray 5 by the paper feed roller 6 is conveyed along the curved guide plate 11 in the diagonal feeding section 10, the paper is transported by the upper guide 16 and the paper presser. The upper surface is regulated by the member 15, and the lower surface of the paper is provided on the curved guide plate 11 and is conveyed while sliding on the curved guide plates 112-14.

Therefore, as described above, the paper is introduced into the paper aligning device 1 with the corner portion separated from the reference line, and the paper is positioned in the paper aligning device 1.

The image forming apparatus shown in FIG. 3 transports paper from a paper tray 5 disposed at the bottom of the apparatus through an upwardly curved paper transport path toward an image transfer section, and feeds the paper toward the image transfer section. This shows the case of a type of device.

In the image forming apparatus shown in FIG. 3, the paper conveyance path from the paper feed section to the sheet alignment device 1 is curved upward, and the sheet conveyance path is configured as a diagonal feeding section 10. In the image forming apparatus, as well, with the configuration described above, a photosensitive drum and a paper register means are provided downstream of the paper alignment device 11, as in the case of FIG. .

As shown in FIG. 3, the diagonal feeding section 10 has a plurality of ribs 1 having different heights and lengths on the inside of the curved guide plate 11.
2 to 14 are arranged, and a pressing roller 17 is arranged corresponding to the rib.
．． 18 is provided, and while the paper is pressed against the surface of the rib by the roller that freely rotates following the moving speed of the paper,
Performs the action of transporting paper. Note that the pressing roller is used when the pressing action cannot be performed satisfactorily depending on the sheet-like member, as in the case of Fig. 1a, but any pressing means other than the roller may be used. It is also possible.

As described above, the apparatus of the present invention sets the length of the paper path to be different on the left and right sides in the width direction while the paper is being transported in the paper transport path, and moves the corners of the paper from the reference line. The sheet is configured to be sent toward the sheet aligning device while being separated toward the inside of the sheet conveyance path. Therefore, in the apparatus of the present invention, it is possible to diagonally feed the paper in a natural state without applying any unreasonable action to the paper.

(Example 2) As described above, in addition to the method of using ribs to vary the length of guiding the paper in the medial direction within the paper conveyance path, the present invention also uses the method shown in FIG. Using a conveyance roller device placed in the paper conveyance path on the upstream side of the paper alignment section, diagonal feeding is performed with the corners of the paper being moved away from the reference line toward the inside of the paper conveyance path so that the It is also possible to do so.

In the paper transport device according to the second aspect of the present invention shown in FIG.
A slip roller 20 and two roller elements 21, 22 are arranged.

The slip roller 20 and the roller members 21 and 22 are each provided with one roller for each drive shaft.

The relationship between the three rollers is such that the slip roller 20 is placed near the center of the upper guide of a specific size, the roller member 21 is placed close to the reference line, and the roller member 22 is placed close to the reference line. is placed further away from the reference line than the slip roller. Further, the roller member 2
1 and 22 are arranged at positions separated by an interval X in the transport direction.

Furthermore, in the roller member, a slip roller 20
is composed of a roller member with a small coefficient of friction, and the roller member 2
1.22 is constituted by a roller member with a large friction coefficient, and the conveyance speed of each roller is set as roller member>slip roller.

Further, in order to make the conveying performance of the roller device different, it is also possible to configure the nip pressure of the roller device such that the slip roller is small and the roller member is large. Note that the arrangement relationship between the slip roller and the two roller members can be arbitrarily set according to the paper size most often used in the image forming apparatus to which the present invention is applied.

By using the roller device configured as described above, in the sheet aligning device 10 shown in FIG. 4, the diagonal feeding action in the sheet aligning device is performed as follows.

That is, when the paper sent from the paper feeding device is nipped between the slip roller 20 and the downstream roller member 21, the difference in conveyance speed between both roller devices and the mutual relationship between the nip position , the paper is rotated counterclockwise, and the corner of the paper is fed diagonally in a direction away from the reference line, and the paper is moved from the position pa to the state Pb.

Note that when the paper is fed diagonally between the slip roller 20 and the roller member 21, the conveying force of the roller member is strong, so the slip roller slips on the paper and strongly scrapes the paper. There is no need to worry about
The roller member now performs an auxiliary action for diagonal feeding.

As described above, when a sheet of paper that has been diagonally fed by the roller member 21 is nipped by two roller members, the feeding direction and conveying speed of the two roller members 21 and 22, the nip pressure, etc. By setting the positions to be the same, the paper is sent from position IPb toward the paper alignment section N1 without changing its orientation, as shown at pc.

Note that the two roller members 21 and 22 each have a diameter of 1
Each drive roller and nip roller are arranged facing each other across the paper moving path, and each roller member is composed of two or a large number of narrow rollers coaxially provided. It is also possible to do so.

In the above-described embodiment of the present invention, since the two roller members are arranged with a very short distance X between them, it is difficult to feed the paper diagonally between the slip roller and the upstream roller member. The action to be performed will be performed over a relatively short distance.

In addition, in the example shown in FIG. 4, the distance between the corner of the paper and the reference line is a relatively small value, but the distance is such that the paper is The corners are set so that they do not touch.

In the paper alignment device 1, the diagonal feed roller performs diagonal feeding toward the side guide 2.
The paper is fed for the next process with the side surface of the paper aligned with the reference line.

Therefore, in the apparatus of the present invention, the action of separating the corners of the paper from the reference line can be performed without being affected by the paper size, and problems such as the surface of the paper being strongly rubbed by the wax can be avoided. Occurrence can be prevented.

In the present invention, by providing the diagonal feeding section as described above, the sheet aligning device can align the sheets over a relatively short distance, and the sheets hit the side guides strongly, causing the corners to fold. Inconveniences such as bending can be prevented.

Furthermore, the paper alignment device of the image forming apparatus of the present invention is not only applicable to electronic copying machines as described above, but also applies to laser printers and other devices that use cut paper. It is possible to apply.

(Effects of the Invention) Since the paper alignment device of the image forming apparatus of the present invention has the above-described configuration, ribs of different lengths etc. are provided on the paper conveyance path as in the first aspect of the present invention. When the paper is transported between the paper feed section and the paper alignment device, the corners of the paper are slanted from the reference line toward the inside of the paper transport path. It is not necessary to provide a conventional means such as a taber roller, and the configuration of the paper alignment section can be simplified.

Further, since the paper being conveyed through the paper conveyance path can be fed diagonally in a natural manner, damage to the paper can be prevented.

Furthermore, in the apparatus of the present invention, the distance for paper alignment in the paper alignment section can be shortened, and the paper conveyance device of the image forming apparatus including the paper conveyance path can be configured to be compact.

In the second aspect of the present invention, the sheet diagonal feeding means is constituted by a slip roller and a roller member, and the conveyance speed between the slip roller and the upstream roller member and the nip position with respect to the sheet are adjusted depending on the width. By setting a difference in both the direction and the feeding direction, a diagonal feeding effect is generated on the paper due to the mutual action of the rollers, so that the paper is The corners can be easily separated from the reference line.

By configuring as described above, the positioning of the corners of the paper with respect to the side guides is maintained constant regardless of the paper size, and the alignment action in the paper alignment device can be performed satisfactorily.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the configuration of a paper aligning device of an image forming apparatus of the present invention, FIG. 1a is a side view thereof, and FIG. 2 is an explanatory diagram when the diagonal feeding section of the present invention is applied to an image forming apparatus. , FIG. 3 is an explanatory diagram when applied to an image forming apparatus having a configuration different from that in FIG. 2, FIG. 4 is an explanatory diagram of another embodiment of the diagonal feeding section of the present invention, and FIG. 5 is an explanatory diagram of a conventional paper sheet. FIG. 6 is a plan view showing the configuration of the aligning device, and FIG. 6 is an explanatory diagram when the state in which the corners of the paper are separated from the side guides differs depending on the paper size. Reference numerals in the figure 1...Paper aligning section, 2...Side guide, 3...Diagonal feed roller, 4...Taper roller, 5...Self...・Paper tray, 10...
・Diagonal feed section, 11...Curved guide plate, 12~
14... Rib, 15... Paper pressing member,
17・18...press roller, 20...
Slip roller, 21, 22...0-ra member.

Claims (2)

[Claims] (1) A guide means is arranged on the side of the paper conveyance path as a reference line for paper feeding, a roller is arranged to feed the paper diagonally toward the guide means, and one side of the paper is positioned by the guide means. In the paper conveyance device, the paper conveyance path on the upstream side of the alignment device is provided with means for guiding both sides of the paper in the width direction so that the conveyance distance is short on the guide means side and long on the widthwise side. A paper conveying device for an image forming apparatus, comprising: (2) A guide means is arranged on the side of the paper conveyance path as a reference line for paper feeding, a roller is arranged to feed the paper obliquely toward the guide means, and one side of the paper is positioned by the guide means. In the sheet conveying device, a slip roller is disposed approximately in the center of the sheet conveying path on the upstream side of the sheet aligning device, and a slip roller is disposed on each of the guide means side and the other side downstream of the slip roller. A sheet aligning device for an image forming apparatus, characterized in that a roller member is provided, and a guide means side roller member is disposed upstream of a roller member on the other side.