JPH1179476A - Laterally paper correcting mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly performing the positional correction of a paper sheet in lateral direction by suppressing deformation for smooth feeding of the paper sheet. SOLUTION: A correction mechanism is structured so that a guide member 16 is disposed along a paper sheet feeding path, and a paper sheet P is fed aslant by a slanted roller 20 until it is brought in contact with the guide surface 16a of the guide member 16 so as to correct a sheet position in lateral direction of the paper sheet feeding path. Also the slanted roller 20 is driven at least while the paper sheet passes the slanted roller 20. In addition, the guide surface 16a of the guide member 16 is formed by coating the surface of the materials of the guide member 16 with fluororesin so that the paper sheet P can be fed very smoothly in the paper sheet feeding direction due to the state of contact with the side part of the paper sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper width direction correcting mechanism applied to an image forming apparatus such as a copying machine and a printer.

[0002]

2. Description of the Related Art Conventionally, as a paper width direction correcting mechanism as described above, for example, there is a mechanism disclosed in Japanese Patent Application Laid-Open No. 7-89645.

In this mechanism, a side guide is provided along a paper transport path, and a skew roller is provided corresponding to the side guide. Then, the fed sheet is skewed and conveyed by the skew roller, so that the side portion of the sheet comes into contact with the side guide, and the position of the sheet in the sheet conveyance path in the width direction is corrected, that is, in the direction orthogonal to the conveyance direction. Is corrected.

In this mechanism, the skew roller can be displaced between a drive position in contact with the sheet and a retracted position separated from the sheet, and is disposed immediately upstream of the skew roller (upstream in the sheet transport direction). The conveyance roller pair is configured to be switchable between a pressurized state in which the sheet is nipped on the sheet and a non-pressurized state. Then, when feeding the paper, the transport roller pair is set in a pressurized state, the paper is transported by the transport roller pair, and the sensor detects that the leading end of the paper has reached a position corresponding to the skew roller. Then, the skew roller is set to the driving position, and the pair of conveying rollers is set in a non-pressurized state. When it is detected that the paper position correction has been completed,
The skew roller is reset to the retracted position, and the conveying roller pair is switched to a pressurized state. Thereafter, the sheet is conveyed downstream by driving the conveying roller pair.

[0005]

In the above-mentioned conventional paper width direction correcting mechanism, the skew roller can be displaced between the drive position and the retreat position as described above, and when the position correction of the paper is completed, the skew roller is displaced. Is reset to the retracted position, so that the skew force by the skew rollers does not act more than necessary on the sheet whose position has been corrected. Therefore, there is a characteristic that the sheet hardly bends while the sheet is skewed and abutted on the side guide.

However, since the skew roller is immediately moved to the retracted position after the position correction, there is a possibility that the sheet once corrected is shifted in the width direction again. Therefore, position correction cannot be performed appropriately.

Further, after the position correction, the sheet is conveyed only by the pair of conveying rollers disposed on the upstream side of the skew roller, which causes a problem that the conveyance is liable to occur.

That is, after the position is corrected, the sheet is in contact with the side guide, so that conveyance resistance is generated due to friction. However, when the sheet is conveyed by the conveyance roller pair as described above, mainly the sheet is rearward. End part (rear end part in the traveling direction)
Is conveyed by nipping, the conveyance at the leading end side of the paper is liable to be delayed due to the friction and the gradient of the paper conveyance path, and the conveyance failure is easily induced. Therefore, it is necessary to improve the paper after the position correction so that the paper can be transported more smoothly.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and a paper width direction correcting mechanism capable of appropriately correcting the position in the paper width direction while smoothly transporting the paper while suppressing bending. It is intended to provide.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a reference member installed in a paper transport direction along a paper transport path, and skews the paper with respect to the transport direction. A skew roller, wherein the skew roller causes the sheet to abut on the reference member to correct the position of the sheet in the width direction of the sheet conveyance path. And a skew roller configured to drive the skew roller relative to the sheet while at least each sheet passes through the skew roller. .

According to this mechanism, since the skew roller is driven until the sheet passes through the skew roller, after the side of the sheet in the traveling direction abuts the reference member, that is, after the position correction is completed. Also, the skew force is continuously applied to the sheet. Therefore, the sheet does not separate from the reference member. In addition, since the skew roller is driven with respect to the sheet even after the position correction, the position of the skew roller is retracted after the position correction, and the conventional skew feeding device feeds the sheet only by the pair of conveying rollers on the upstream side. By comparison, the conveying force can be applied to the leading end side of the sheet. Therefore, the paper can be smoothly transported without delay. In addition, since the reference member has a conveyance resistance reducing structure and the resistance in the conveyance direction acting on the sheet due to contact with the reference member is small, even if the skew roller continues to be driven as described above after the position correction, Difficult to bend. The “transportation resistance reducing structure” is a structure that can reduce the hindrance of the conveyance of the sheet due to the contact with the reference member, and reduces the “transportation resistance” itself to smoothly convey the sheet. In addition to the passive structure described above, it also includes a positive structure that smoothly conveys a sheet by positively applying a conveying force to the sheet.

The reference member can be formed of a low-friction material as the transport resistance reducing structure. According to this configuration, the above-described effects can be obtained with a very simple configuration.

As the transport resistance reducing structure, it is conceivable that the reference member is constituted by a rotating body rotatable about an axis perpendicular to the paper transport surface (claim 3). The rollers are arranged side by side, and the rollers are arranged so that a plane commonly in contact with each roller peripheral surface is parallel to the sheet conveying direction (Claim 4). Alternatively, a pair of rollers are arranged in the sheet conveying direction. Endless belts may be attached to these pulleys, and the belt may be arranged so that the surface of the belt that comes into contact with the paper is parallel to the paper conveyance direction. According to these configurations, the position of the sheet is corrected by contacting the side of the sheet in the traveling direction with a roller or a belt. At this time, when the sheet comes into contact with the roller or the belt, the roller or the belt rotates, thereby reducing the conveyance resistance acting on the sheet due to the contact with the reference member.

In particular, in the mechanism according to any one of claims 3 to 5, if the rotating body is driven to rotate in a direction of applying a conveying force to the sheet by contact with the sheet (claim 6), the position correction is performed. Thereafter, since a transport force is applied to the sheet from the reference member, the sheet transport is promoted. In addition, the force in the combined direction of the conveying force by the rotating body and the skew force by the skew roller,
That is, a force in a direction more parallel to the transport direction acts on the sheet, and the skew force acting on the sheet is reduced. As a result, the paper is less likely to bend.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a sheet conveying path of a copying machine to which the sheet width direction correcting mechanism of the present invention is applied. For example, the sheet conveying path is located immediately upstream of a pair of registration rollers for aligning the leading end of the sheet, that is, in the sheet conveying direction. The right upstream side is shown.

In the sheet conveying path 10A shown in FIG. 1, pairs of conveying rollers 12, 14 are provided in order from the upstream side (right side in FIG. 1) in the sheet conveying direction.
4, a guide member 16 (reference member) is provided, and a skew roller 20 for skew-feeding the paper toward the guide member 16 is provided at a position closer to the center than the guide member 16. Has been established.

The skew roller 20 is supported by a mounting member 22, and is mounted on the frame of the copying machine via the mounting member 22 such that the roller 20 contacts the sheet. The rotating shaft 21 of the skew roller 20 is connected to a drive shaft 24 supported by the frame via a universal joint 25 as shown in FIG. The drive shaft 24 is connected to a drive motor via a torque transmission means such as a gear (not shown) so that the skew roller 20 rotates by receiving the rotation drive force of the drive motor. Has become.

The guide member 16 is provided on the sheet transport path 10A.
Is arranged near one end (near the front end in FIG. 1) in the width direction of the paper, that is, in the direction orthogonal to the conveyance direction on the paper conveyance surface, and on the paper conveyance path side (the upper side in FIG. 1). A guide surface 16a is formed in parallel with the sheet transport direction.

The guide surface 16a is formed by coating the surface of the material of the guide member 16 with a fluororesin, so that the sheet P can be moved very smoothly in the state of contact with the side of the sheet. It can be moved to.

In FIG. 1, reference numerals 26 and 28 denote sensors for detecting a sheet embedded on the sheet conveying surface immediately downstream of the pair of conveying rollers 12 and 14, that is, downstream of the sheet conveying direction. is there. These sensors 26, 28
For example, the reflection type sensor is configured to detect the presence or absence of the sheet by reflecting the irradiated light on the sheet and receiving the light. During the operation of the copying machine, the operation timing of the skew roller 20 is determined based on the detection of the sheet by the sensors 26 and 28, as described later. In particular, the sensor 28
The sheet P is disposed so as to detect the leading end of the sheet P at a position where the rear end portion of the sheet P has completely passed the skew roller 20.

In the above configuration, the fed sheet P is sent in the direction shown by the white arrow in FIG. When the sheet passes through the pair of transport rollers 12 and the leading end of the sheet is detected by the sensor 26, the rotational driving force of the drive motor is transmitted to the skew roller 20 in accordance with the operation of a solenoid (not shown). You.

When the sheet P is further conveyed and its leading end reaches the skew roller 20, the sheet P is fed by the conveying roller pair 12 and the skew roller 20, and the skew force of the skew roller 20 acts. Then, the sheet P is skewed toward the guide member 16. As a result, the side of the sheet P gradually comes into contact with the guide surface 16a from the leading end side and the guide surface 1a.
6a, the position of the paper P in the width direction in the paper transport path 10A is corrected as shown in FIG.

When the sheet P is further conveyed and passes through the pair of conveying rollers 14 and the leading end thereof is detected by the sensor 28, that is, when the sheet P completely passes through the skew roller 20, the solenoid is actuated. The transmission of the rotational driving force to the skew roller 20 is interrupted in response to the
4, the paper P is sent to the downstream side.

According to the above configuration, regardless of whether the position correction of the sheet P has been completed or not, the sheet P is completely
Skew roller 20 is driven until it passes. Therefore, the skew force of the skew roller 20 always acts on the paper P, and the state where the side of the paper P is completely in contact with the guide surface 16a, that is, the position after the position correction is maintained. In this state, the sheet P is transported downstream.

Therefore, there is no danger that the sheet whose position has been corrected will shift again, unlike a conventional mechanism of this type in which the skew roller is immediately moved to the retracted position immediately after the position of the sheet is corrected. The position correction in the width direction in the sheet transport path 10A is surely performed.

Until the sheet P completely passes through the pair of conveying rollers 12, the sheet P is conveyed by the pair of conveying rollers 12 and the skew roller 20 on the downstream side thereof. Compared to a conventional device of this type in which the rollers are retracted and the sheet is conveyed only by the conveying roller pair on the upstream side, a larger conveying force can be applied, and the conveying force can be applied to the leading end side of the sheet P. Can be granted. Therefore, in the conveyance of the sheet P after the position correction, the sheet P can be smoothly conveyed without delaying the conveyance on the leading end side of the sheet.

Further, the guide surface 16a is formed by the fluororesin coating as described above,
Is very good,
After the position correction, the bending of the sheet P can be suppressed while the skew roller 20 continues to apply the skew force to the sheet P as described above.

That is, in a general position correction mechanism of this kind, if the sheet is continuously applied with a skew force after the position correction, the sheet is bent because the friction between the sheet and the guide surface causes a large conveyance to the sheet. This is due to the resistance acting. Therefore, in the above-described configuration in which the guide surface 16a is formed of the fluororesin coating, the conveyance resistance acting on the sheet P due to the contact between the sheet P and the guide surface 16a is extremely small. The paper P is hardly bent even if is continuously driven.

Therefore, according to the above configuration, the paper P can be smoothly transported without hindering the transportability of the paper P while reliably performing the position correction in the paper width direction.

In the above configuration, the guide surface 16a is formed by applying a fluororesin coating to the material of the guide member 16 as one of the low-friction materials. Of course, other low-friction materials such as polyethylene The guide surface 16a may be formed by coating a material such as. Further, other than forming the guide surface 16a by coating the low friction material as described above, the guide member 16 itself may be formed of a low friction material.

By the way, various modifications (second to fifth embodiments) can be considered for the configuration of the paper transport path 10A, and these modifications will be described below. In addition,
The configuration described below is also basically the same as the paper transport path 10A shown in FIG. 1, and therefore, the same members will be denoted by the same reference numerals and description thereof will be omitted, and only differences will be described in detail. I will do it.

FIG. 3 shows a sheet transport path 10B according to the second embodiment. Paper transport path 10B shown in FIG.
In this embodiment, a plurality of rollers 30 are arranged in a line in the transport direction of the sheet P as shown in FIG. Each roller 3
Numeral 0 is arranged so that a virtual plane commonly in contact with each roller peripheral surface is parallel to the paper transport direction, and is rotatably supported via a bearing on a support shaft 31 perpendicular to the transport surface of the paper transport path 10. ing. As a result, the position correction is performed when the sheet P comes into contact with the peripheral surface of each roller 30. In the drawing, reference numeral 32 denotes a protection plate disposed on the paper transport path 10B, and although not shown in detail, the peripheral surface of each roller 30 is cut through a notch formed in the protection plate 32. The sheet P faces the transport path side.

In this configuration, the position correction is performed by the sheet P abutting on the roller 30 as described above. At this time, when the sheet P comes into contact with the roller 30, the roller 30 moves smoothly in the transport direction of the sheet P. To rotate. Therefore, paper P
The conveyance resistance acting on the sheet P due to the contact between the sheet P and the roller 30 is extremely small, and the sheet P is unlikely to bend even if the skew roller 20 is continuously driven after the position correction. Therefore, also in the case of this configuration, the position correction in the paper width direction can be appropriately performed while smoothly transporting the paper P, as in the first embodiment.

FIG. 4 shows a sheet transport path 10C according to the third embodiment. Paper transport path 10C shown in FIG.
As shown in the figure, a pair of pulleys 34 are disposed apart from each other in the transport direction of the paper P, and an endless belt 36 is mounted over the pulleys 34 to form the guide member 16. Each pulley 34 is rotatably supported via a bearing on a support shaft 35 that is perpendicular to the transport surface of the paper transport path 10.
The surface of the belt 36 attached to the pulley 4 is parallel to the paper transport direction between the pulleys 34 and faces the transport path of the paper P via a cutout formed in the protection plate 32. .

According to this configuration, the position correction is performed when the sheet P comes into contact with the surface of the belt 36. At this time, when the sheet P comes into contact with the belt 36, the belt 36 smoothly rotates in the transport direction of the sheet P.
Therefore, the conveyance resistance acting on the sheet P due to the contact between the sheet P and the guide member 16 is small, and the sheet P is unlikely to bend even if the skew roller 20 is continuously driven after the position correction. Therefore, also in this case, the same effect as in the first embodiment can be obtained.

FIG. 5 shows a paper transport path 10D according to the fourth embodiment. Paper transport path 10D shown in FIG.
Correspond to each roller 30 in the paper transport path 10B shown in FIG.
Is driven to rotate.

That is, in this configuration, the support shaft 31 is rotatably supported by the frame of the copying machine via the bearing, and each roller 30 is fixed to the support shaft 31 so that it can rotate integrally with the support shaft 31. Has become. A timing pulley 38 is mounted on each support shaft 31,
A tension pulley 42 is disposed near each support shaft 31, and the timing pulley 38, the tension pulley 42, and the pulley 4 mounted on the output shaft of the motor 40 are provided.
The timing belt 44 is attached to the first and second belts. Thus, the respective rollers 30 are integrally rotated at the same speed in the same direction in accordance with the driving of the motor 40.

In this configuration, the skew roller 20 is operated at the same timing as in the first embodiment, and the motor 40 is driven at the same timing as the operation timing of the skew roller 20. At this time, when the sheet P comes into contact with the roller 30, the roller 30 is rotationally driven so that a conveying force acts on the sheet P by the roller 30. Specifically, each roller 3
0 is rotated counterclockwise in FIG.

In this manner, when the sheet P is brought into contact with the peripheral surface of the roller 30 and the position is corrected, since each roller 30 is driven to rotate, the conveying force is applied to the sheet P by the roller 30. Is given. Therefore, a combined force of the conveying force of the roller 30 and the skew force of the skew roller 20, that is, a force in a direction more parallel to the conveyance direction acts on the sheet P after the position correction. Therefore, after position correction,
The skew force acting on the paper P is reduced, and as a result, the deflection of the paper P is effectively suppressed.

Therefore, even in the configuration of the paper transport path 10D, the position correction in the paper width direction can be appropriately performed while smoothly transporting the paper P similarly to the paper transport paths 10A to 10C. .

In the sheet conveying path 10D, after the position is corrected, the side of the sheet comes into contact with the roller 30 over a wide range from the leading end to the trailing end. , It is possible to apply a larger conveying force to the sheet P after the position correction,
A conveying force can be applied to the leading end side of the paper P.
Therefore, there is an advantage that a phenomenon in which the conveyance of the leading end side of the sheet is delayed in the conveyance of the sheet P after the position correction can be more effectively avoided.

FIG. 6 shows a sheet transport path 10E according to the fifth embodiment. Paper transport path 10E shown in FIG.
Is a belt 36 in the sheet conveyance path 10C shown in FIG.
Is driven to rotate.

That is, in this configuration, the support shaft 35 on one side (the right side in the figure) is rotatably supported by the frame of the copying machine via the bearing, and the pulley 34 is fixed to the support shaft 35 to be supported. It can rotate integrally with the shaft 35. Then, a timing pulley 46 is mounted on the support shaft 35, and a timing belt 52 is mounted over the timing pulley 46 and a pulley 50 mounted on the output shaft of the motor 48, so that the motor 4
8, the belt 36 is driven to rotate in one direction at a constant speed.

Also in this case, the motor 48 is driven at the same timing as the operation timing of the skew roller 20,
By rotating the belt 36 in the counterclockwise direction in the figure, the belt 36 applies a conveying force to the sheet P after the position correction, similarly to the sheet conveying path 10D of the fourth embodiment. Is done. Therefore, a force in a direction more parallel to the transport direction acts on the sheet P after the position correction, and as a result, the deflection of the sheet P is effectively suppressed. Therefore, the same effect as in the first embodiment can be obtained also in the case of such a paper transport path 10E.

The paper transport path described in each of the above embodiments is an example of a part of the paper transport path to which the paper width direction correcting mechanism of the present invention is applied. The specific configuration of the paper width direction correction mechanism can be appropriately changed without departing from the gist of the present invention. For example, in the above-described embodiment, as the transport resistance reducing structure, the guide member 16 is formed by applying a fluororesin coating to the material of the guide member 16 to form the guide surface 16a, or by a rotating member such as a plurality of rotatable rollers 30 and a belt 36. 16 or the roller 30 or the belt 36 is driven to rotate, but other structures may be employed as the transport resistance reducing structure.
What is necessary is just to employ | adopt suitably the structure which can reduce effectively that the conveyance of the paper P is obstructed by the contact with the guide member 16. FIG.

In the above embodiment, an example in which the paper width direction correcting mechanism of the present invention is applied to a copying machine has been described. However, the above mechanism of the present invention is applicable to an image forming apparatus such as a printer or a facsimile other than the copying machine. Of course, it is applicable.

[0048]

As described above, the present invention relates to a paper width direction correcting mechanism in which a sheet is brought into contact with a reference member by a skew roller to correct the width of a sheet being conveyed in the width direction. Since the skew roller is driven relative to the sheet at least while each sheet passes through the skew roller, the position of the corrected sheet can be reliably maintained, and the position correction can be performed. After time, the sheet can be conveyed by applying a conveying force to the leading end side of the sheet.
In addition, since the reference member has a conveyance resistance reducing structure that reduces the conveyance resistance acting on the sheet, the sheet hardly bends even if the skew roller continues to be driven as described above after the position correction. Accordingly, the position of the sheet can be reliably corrected without impairing the sheet transportability.

In particular, if the reference member is formed of a low friction material as the transport resistance reducing structure, the above-described effects can be obtained with a very simple configuration.

Further, if the reference member is constituted by a rotating member rotatable about an axis perpendicular to the sheet carrying surface as the above-described transport resistance reducing structure, the rotating member rotates upon contact with the sheet during position correction. Can be effectively reduced. In particular, if the rotator is driven to rotate in the direction in which the sheet is conveyed with the conveying force, the sheet can be conveyed after the position correction, so that the sheet can be conveyed. In addition, a force in the combined direction of the conveying force of the rotating body and the skew force of the skew roller, that is, a force more parallel to the conveying direction can be applied to the sheet, and as a result, the sheet can be hardly bent.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing a sheet conveying path (first embodiment) of a copying machine to which a sheet width direction correcting mechanism according to the present invention is applied.

FIG. 2 is a schematic diagram illustrating position correction in the width direction of a sheet.

FIG. 3 is a schematic plan view showing a sheet conveying path (second embodiment) of a copying machine to which a sheet width direction correcting mechanism according to the present invention is applied.

FIG. 4 is a schematic plan view showing a sheet conveying path (third embodiment) of a copying machine to which a sheet width direction correcting mechanism according to the present invention is applied.

FIG. 5 is a schematic plan view showing a sheet transport path (fourth embodiment) of a copying machine to which a sheet width direction correcting mechanism according to the present invention is applied.

FIG. 6 is a schematic plan view showing a sheet transport path (fifth embodiment) of a copying machine to which a sheet width direction correcting mechanism according to the present invention is applied.

[Explanation of symbols]

 Reference Signs List 10 paper transport path 12, 14 transport roller pair 16 guide member 16a guide surface 20 skew roller 26, 28 sensor P paper

Claims (6)

[Claims] A reference member provided in a paper transport direction along a paper transport path; and a skew roller for skewing the paper with respect to the transport direction. In the paper width direction correction mechanism that abuts against a member and corrects the position of the paper in the width direction of the paper transport path, the reference member has a transport resistance reducing structure that reduces the transport resistance acting on the paper, A sheet width direction correcting mechanism, wherein the skew roller is driven relative to the sheet while at least each sheet passes through the skew roller. 2. The paper width direction correcting mechanism according to claim 1, wherein said reference member is formed of a low friction material. 3. The paper width direction correcting mechanism according to claim 1, wherein said reference member is constituted by a rotating body rotatable about an axis perpendicular to the paper conveying surface. 4. The rotating body is composed of a plurality of rollers arranged in parallel in the paper transport direction, and the rollers are arranged such that a plane common to each roller peripheral surface is parallel to the paper transport direction. 4. The paper width direction correcting mechanism according to claim 3, wherein: 5. The rotating body comprises a pair of pulleys juxtaposed in a sheet conveying direction and an endless belt mounted on the pulleys, and a surface of the belt abutting on the sheet is aligned with the sheet conveying direction. 4. The paper width direction correcting mechanism according to claim 3, wherein the paper width direction correcting mechanism is arranged so as to be parallel. 6. The paper width direction correcting mechanism according to claim 3, wherein said rotating body is driven to rotate in a direction of applying a conveying force to said paper by contact with said paper. .