JPH0419000Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a sheet member conveying device in a copying machine, etc., and more specifically, a pair of feeding rollers for feeding a sheet member, and The present invention relates to a sheet member conveying device including a temporary blocking means disposed downstream of the sheet member for temporarily blocking the advance of the sheet member fed by the pair of feeding rollers.

(Prior Art) Conventionally, in an electrostatic copying machine equipped with a manual paper feed mechanism, in order to prevent the sheet member from being skewed, or to prevent the sheet member from being skewed, the toner image on the rotating drum having a photoreceptor on the circumferential surface and the sheet member In order to synchronize the sheet members, a pair of registration rollers are provided, the rotation of which is controlled by a clutch or the like, and serves as a temporary stopping means for temporarily keeping the sheet member in a stopped state. On the upstream side of the pair of registration rollers in the conveyance direction, a pair of feed rollers are arranged that are constantly rotating and drive to convey the sheet member so that it is sandwiched between the pair of registration rollers whose drive is stopped by the action of a clutch. . This feed roller pair is made of a metal material and includes a lower roller that is a driving roller, and a synthetic resin material that is configured to press the lower roller with its own weight in order to cooperate with the lower roller to pinch and convey the sheet member. Alternatively, it is composed of an upper roller made of a metal material. With the above configuration, the sheet member fed manually is conveyed by a pair of feed rollers that are constantly driven to rotate, and is temporarily stopped by a pair of registration rollers whose drive is stopped. The tip is corrected, that is, the skew feed is corrected. Next, the sheet member that has been temporarily stopped is conveyed again by a pair of registration rollers whose drive is controlled in synchronization with the movement of the photoreceptor.

(Problem to be solved by the invention) In such prior art, the lower roller of the feeding roller pair is always driven to rotate in the conveying direction with respect to the sheet member that is temporarily stopped. . Therefore, the sheet member and the lower roller are maintained in a slipped state,
There was a problem in that the back side of the sheet member was stained by the circumferential surface of the lower roller made of a metal material, and that it could not be applied particularly to sheet members that required double-sided copying. Furthermore, in such a configuration, the frictional force (conveying force) between the sheet member and the lower roller is set by the weight of the upper roller of the pair of feeding rollers, so thin sheet members with weak stiffness are Even though the leading end is stopped, paper jams occur because the paper is being conveyed, and stiff, thin sheets, etc. cannot be sufficiently pinched by the pair of registration rollers whose leading end is stopped. However, there was a problem in that the leading edge correction could not be performed sufficiently and the manual paper feed mechanism provided for various sheet members could no longer fulfill its original role.

One possible solution to the above problem is to transmit the drive to the lower roller, which is the drive roller of the pair of feed rollers, via a clutch, but it should be noted that the drive roller of the pair of registration rollers also requires a clutch. When you think about it, there are problems with the complexity and accuracy of control such as how to engage the clutch between the roller pairs.
Furthermore, there is the problem of increased costs, making it difficult to apply to copying machines and the like that require miniaturization and cost reduction.

(Means for Solving the Problems) According to the present invention, there is provided a pair of feeding rollers for feeding a sheet member, and a pair of feeding rollers disposed downstream of the pair of feeding rollers, a temporary blocking means for temporarily blocking the forward movement of the fed sheet member; the feeding roller pair includes a drive shaft rotationally driven by a drive source, and a drive shaft spaced apart from the drive shaft; In a sheet member conveying device that nip and feed a sheet member between an arranged driven shaft, a plurality of drive rollers attached to the drive shaft, and at least one driven roller attached to the driven shaft. , the drive roller includes at least one drive roller and at least one loosely inserted roller, and the drive roller is mounted on the drive shaft so as to be actively rotated as the drive shaft rotates. The loosely inserted roller has substantially the same wall thickness as the drive roller, and is loosely inserted into the drive shaft, and the sheet member being fed by the feeding roller pair. When the forward movement of the loosely inserted roller is blocked by the temporary blocking means, the rotation of the loosely inserted roller is prevented by the resistance applied from the sheet member to the loosely inserted roller even though the drive shaft is rotationally driven. A sheet member conveying device is provided, which is characterized in that it can be stopped.

(Function) Since the structure is as described above, the sheet member can be reliably conveyed to the temporary blocking means by the drive rollers to which the drive shaft is transmitted, and the leading edge can be corrected, and the sheet member can be By being stopped by the temporary blocking means, the resistance applied from the sheet member to the loosely inserted roller causes
The rotation of the loose insertion roller is stopped.

(Embodiments) Hereinafter, preferred embodiments constructed according to the present invention will be described with reference to the accompanying drawings.

First, to outline the overall structure of an electrostatic copying machine constructed according to the present invention with reference to FIG. 4 is rotatably attached. Around the rotating drum 4, which is rotated in the direction shown by the arrow 6, there are installed a charging corona discharger 8, an optical system 10, a developing device 12, a transfer corona discharger 14, and a peeling corona discharger, which are arranged in order in the direction of rotation. A corona discharger 16, a cleaning device 20 having a cleaning blade 18, and a static elimination lamp 22 are provided. Further, a document irradiation lamp 24 is provided in association with the optical system 10. This original irradiation lamp 24 is inserted into the original placing means 3 through an opening 28 formed in the upper plate 26 of the housing 2.
The original to be copied (not shown) placed on the transparent plate 32 of No. 0 is irradiated. An optical system 1 constituted by arranging a large number of elongated optical elements extending in the vertical direction (for example, rod-shaped lenses sold by Nippon Sheet Glass Co., Ltd. under the trade name "Self-Ox Micro Lens") in the front-back direction.
0 projects the reflected light from the document onto the circumferential surface of the rotating drum 4, as shown by the arrow in FIG.

Approximately the lower half of the housing 2 is marked with the number 34 as a whole.
A sheet member conveying device shown in is provided. At one end of this sheet member conveyance device 34, at the right end in FIG.
and a manual sheet member feeding device 38 located above it. The copy paper supply device 36 includes a copy paper cassette receiver 42 provided with a feeding roller 40, and a copy paper cassette loaded into the copy paper cassette receiver 42 through an opening 44 formed on the right side of the housing 2. 46, and by the action of the feeding roller 40, the copy paper is fed one by one from the sheet member copy paper layer 48 housed in the copy paper cassette 46. The manual sheet member feeding device 38 includes a manual feed table 52 for feeding the sheet member P through an opening 50 formed on the right side of the housing 2;
It includes a pair of upper and lower guide plates 54 and 56, and a pair of feed rollers 58 and 60 located downstream of these guide plates 54 and 56 (left side in FIG. 2). When a suitable sheet member P such as a sheet of copy paper is positioned on the manual feed table 52 and advanced to the nip position of the pair of feed rollers 58 and 60, the pair of feed rollers 58 and 60 transfer the sheet member P.
Nip and feed this. Copy paper supply device 3
The copy paper fed from 6 through between the guide plates 62 and 64, or the sheet member P fed from the sheet member feeding device 38 through between the guide plates 64 and 66, is moved by a pair of registration rollers serving as temporary blocking means. 68 and 70 prevent its advancement. Meanwhile, while the rotating drum 4 is rotated in the direction shown by the arrow 6, the charging corona discharger 8 charges the photoreceptor substantially uniformly to a specific polarity, and then the optical system 1
0, the image of the original is projected onto the photoreceptor (at this time, the original document mounting means 30
The scanning exposure movement is performed from the scanning exposure start position indicated by 0A to the right in FIG. 2), thus forming an electrostatic latent image corresponding to the original on the photoreceptor. Thereafter, development device 12 applies toner particles to the electrostatic latent image on the photoreceptor to develop the electrostatic latent image into a toner image. Next, the pair of registration rollers 68 and 70 are installed as described above.
The sheet member P was temporarily stopped by
is transported in synchronization with the toner image on the photoreceptor. A transfer corona discharger 1 is attached to the conveyed sheet member P.
The toner image on the photoreceptor is transferred by the action of 4, and is peeled off from the photoreceptor by the action of the peeling corona discharger 16. The sheet member P on which the toner image has been transferred is conveyed by an appropriate conveyance belt mechanism 76 and sent to a fixing device 78 . The sheet member P on which the toner image has been fixed in the fixing device 78 is discharged onto a receiving tray 84 by the action of a pair of discharge rollers 80 and 82 . On the other hand, the rotary drum 4 continues to rotate, and the cleaning device 20 removes residual toner particles from the photoreceptor, and the discharge lamp 22 causes the residual charge on the photoreceptor to disappear.

Next, the sheet member conveying device according to the present invention will be described in detail with reference to FIGS. 1, 3, and 4. Third
The figure is an enlarged view of the vicinity of the pair of registration rollers 68 and 70 and the pair of feeding rollers 58 and 60 in FIG.
In order to correct the skew feeding of the sheet member P,
Alternatively, a rotating drum 4 having a photoreceptor on its circumferential surface
In order to synchronize the upper toner image with the sheet member P, the sheet member P is disposed so as to be temporarily in a stopped state. As shown in FIG. 4, the lower roller 70 of this pair of registration rollers is rotatably supported by side walls 88 and 90 in the housing 2, and has a sprocket at one end that transmits driving force from a drive motor (not shown). A spring clutch 94 is provided for selectively transmitting drive to the wheel 92 and the sprocket wheel 92. The upper roller 68 of the registration roller pair is rotatably supported in long holes 96 and 98 provided in side walls 88 and 90 via bushes 97 and 99, and is supported by a spring 1.
This roller is driven by the lower roller 70 by resiliently pressing the lower roller 70 with the rollers 00 and 102.

Registration roller pair 6 in sheet member conveyance direction 86
On the upstream side in the conveyance direction with respect to the pair of registration rollers 68 and 70, there is a sheet member P with respect to the pair of registration rollers 68 and 70.
Guide plates 64 and 66 are disposed close to each other to guide the conveyance.

Furthermore, a pair of feed rollers 58 and 60 are arranged on the upstream side in the conveyance direction.

As shown in FIG. 1, the lower roller 60 of the pair of feeding rollers connects a drive shaft 106 provided to convey the sheet member P via a gear 104 with driving force from a drive motor (not shown). It consists of a loosely inserted roller 108 that is loosely inserted into the drive shaft 106, and a drive roller 116 that transmits the driving force from the drive shaft 106 to the upper roller 58 that is fixed to the other support shaft 107. Therefore, the lower roller 60 constitutes a driving roller, and the upper roller 58 constitutes a driven roller. Like the drive shaft 106 and the lower roller 70 of the pair of registration rollers, it is rotatably supported on the side walls 88 and 90 in the housing 2 .

Next, referring to FIG. 1, the loosely inserted roller 108
and the driving roller 116 will be explained. The loosely inserted roller 108 and the drive roller 116 are made of a material with a small friction coefficient such as a synthetic resin material, and the inner diameter D ₁ of the loosely inserted roller 108 is larger than the outer diameter of the drive shaft 106 (D ₁ >
d), and the loosely inserted roller 108 is loosely inserted into the drive shaft 106 in a suspended state.

On the other hand, the inner diameter D ₂ of the drive roller 16 is
6 (D ₂ =d), the drive roller 116 is attached to the drive shaft 106 in a substantially fixed state.

Furthermore, the wall thicknesses t ₁ and t ₂ of the loosely inserted roller 108 and the driving roller 116 are formed to be equal (t ₁ =t ₂ ).

Since the lower roller 6 is configured accordingly,
The circumferential surfaces of the loosely inserted roller 108 and the driving roller 116 are always in contact with the upper roller 58 even while the drive is being transmitted from the roller 108 to the upper roller 58 .

Next, the loosely inserted roller 108 and the driving roller 116
To explain the arrangement with respect to the drive shaft 106, the first
As shown in the figure, a pair of drive rollers 116 are arranged symmetrically at a predetermined distance apart from each other with respect to the center of the drive shaft 106, and two pairs of loosely inserted rollers 108 are arranged outside the drive rollers 116 in the axial direction, Each is configured to correspond to JIS standard paper sizes (for example, B4, A4, B5, etc.), and each end is equipped with a stop ring 11.
0, movement in the axial direction is restricted. The upper roller 58 of the feeding roller pair is made of a metal material, and has elongated holes 112 formed in the side walls 88 and 90.
and 114 via bushes 113 and 115, and is brought into contact with the loosely inserted roller 108 and driving roller 116 of the lower roller 60 due to its own weight.

Next, the operation of the sheet member conveying device configured as described above will be explained. Referring to FIGS. 2 and 3, first, the sheet member P that is manually fed is transported by a pair of feeding rollers 58 which are constantly rotationally driven.
and 60 in the transport direction 86. As for drive transmission at this time, as described above with reference to FIG. 1, the driving force from the drive shaft 106 is transmitted to the drive roller 116,
Due to the squeezing force of the upper roller 58 pressed against the roller 16 by its own weight and the own weight of the upper roller 58, the looseness due to the frictional force μ1 between the drive shaft 106 and the inner circumferential surface 108a of the loosely inserted roller 108 (point A in the third figure) is Insert roller 1
The sheet member P is conveyed in the conveyance direction 86 by the rotational drive accompanying the rotation of the drive shaft 106 of 08.

The sheet member P conveyed by the pair of feed rollers 58 and 60 is guided by guide plates 64 and 66 that are disposed close to each other, and its tip reaches the pair of registration rollers 68 and 70 whose drive is stopped. are brought into contact. Even in this state, the drive shaft 106 of the lower roller 60 of the pair of feed rollers continues to rotate, and the leading end of the sheet member P is moved to the pair of registration rollers 68 by the rotation of the drive roller 116.
and 70, and acts to correct the tip of the sheet member P uniformly.

Even when the leading end of the sheet member P is properly corrected and stopped, the drive shaft 106 continues to rotate. The frictional force μ2 acting between the drive shaft 106 and the inner peripheral surface 108a of the loosely inserted roller 108 (point A shown in FIG. 3) is larger than the frictional force μ1 acting between the drive shaft 106 and the inner peripheral surface 108a of the loosely inserted roller 108 (point A shown in FIG. 3). (μ
2>μ1), the loosely inserted rollers 108 and the drive shaft 106 are in a slip state, and the loosely inserted rollers 108 do not rotate, but only the drive shaft 106 rotates. As the sheet member P is stopped by the pair of registration rollers 68 and 70, a frictional force is generated between the sheet member P and the loosely inserted rollers 108, and the loosely inserted rollers 108 are stopped, so that they are not rotated. Since there is only a slip between the circumferential surface of the continuous driving roller 116 and the back side of the sheet member P, there is very little dirt on the back side of the sheet member P, and the simple structure can be used with a wide variety of sheet members. It becomes possible. Furthermore, a guide plate 64 guides the sheet member P with respect to the pair of registration rollers 68 and 70.
By arranging and 66 close to each other, the waist force of the seat member P can be increased, which is more useful.

Then, the sheet member P, which has been temporarily stopped by the pair of registration rollers 68 and 70, is moved by a clutch 94 connected to the lower roller 70 of the pair of registration rollers in synchronization with the movement of the toner image on the rotating drum 4. It is transported again by the action of

Next, other embodiments will be described.

Hereinafter, the same numbers will be used for the same names.

In this embodiment, the width of the driving roller 116 in the axial direction and the width of the loosely inserted roller 108 are configured to be substantially the same, but the width of the driving roller 116 is set to the width of the sheet member P.
If it is shortened within the range that can be conveyed, the sheet member P
Even if a slip occurs on the back side of the sheet member P and the circumferential surface of the driving roller 116, the dirt on the back side of the sheet member P will be extremely small.

Furthermore, as shown in FIG. 5, in the lower roller 60 of the feeding roller pair, the drive rollers 116 and the loosely inserted rollers 108 are arranged alternately with respect to the drive shaft 106, and the drive rollers 116 and loosely inserted rollers 108 are arranged in a staggered manner, and are arranged horizontally with respect to the center of the drive shaft 106. By symmetrically arranging several pairs separated by a predetermined distance, tip correction can be performed extremely easily regardless of the size of the sheet member P, and one drive roller 116
This has the effect that the width can be made short.

Further, in the drive example of the present invention, the explanation has been made based on the pair of conveyance rollers 68 and 70 as temporary blocking means, but control is performed by using an appropriate stop piece that can advance and retreat in the conveying path as the temporary blocking means. You can do it like this.

Further, in the specific example of the present invention, the upper roller 58 of the feeding roller pair is configured to press the lower roller 60 by its own weight, but it goes without saying that the lower roller 60 may be pressed by a spring means. stomach.

(Effects) As described in detail above, according to the present invention, the sheet member can be reliably conveyed to the temporary blocking means by the drive rollers to which the drive shaft is transmitted, and the leading edge can be corrected.

When the sheet member is stopped by the temporary blocking means, the rotation of the loosely inserted roller is stopped by the resistance applied from the sheet member to the loosely inserted roller. It is possible to minimize the amount of dirt on the back of the member, and it is also possible to stably convey various sheet members with a simple configuration.

Further, according to the present invention, even if the circumferential speeds of the temporary stop means and the pair of feeding rollers are set to be different, stable conveyance is possible due to the action of the loosely inserted rollers.

[Brief explanation of drawings]

FIG. 1 is a partial cross-sectional view taken along a plane passing through the axes of a pair of feed rollers, and FIG. 3 is an enlarged view of the sheet member conveying device shown in FIG. 2, FIG. 4 is a partial sectional view taken along a plane passing through the axes of the registration roller pair, and
The figure shows another embodiment of the present invention. 58, 60... Feeding roller pair, 64, 66...
Guide plate, 68, 70... Registration roller pair, 10
6... Drive shaft, 108... Loosely inserted roller, 116...
Drive roller, P... Sheet member.

Claims (1)

[Claims for Utility Model Registration] 1. A pair of feed rollers for feeding a sheet member, and an advancement of the sheet member disposed downstream of the pair of feed rollers and fed by the pair of feed rollers. The pair of feed rollers includes a drive shaft rotationally driven by a drive source, a driven shaft spaced apart from the drive shaft, and a temporary blocking means for temporarily blocking the feed roller pair. In a sheet material conveying device that nips and feeds a sheet material between a plurality of drive rollers mounted on a drive shaft and at least one driven roller mounted on the driven shaft, the drive roller includes at least one driven roller. and at least one loosely inserted roller, the drive roller being mounted on the drive shaft so as to be actively rotated as the drive shaft rotates;
The loosely inserted roller has substantially the same wall thickness as the drive roller, and is loosely inserted into the drive shaft, so that the sheet member being fed by the pair of feeding rollers can move forward. When blocked by the temporary blocking means, the rotation of the loosely inserted roller is stopped due to the resistance applied from the sheet member to the loosely inserted roller even though the drive shaft is rotationally driven. A sheet member conveying device characterized by the following. 2. The drive roller includes: at least one pair of drive rollers arranged symmetrically at a predetermined distance apart from the center of the drive shaft; and at least one pair of drive rollers arranged axially outward of the drive rollers. A sheet member conveying device according to claim 1, characterized in that it comprises a loosely inserted roller. 3. The sheet member conveying device according to claim 1 or 2, wherein the drive roller and the loosely inserted roller are alternately arranged on the drive shaft.