JP3446395B2 - Automatic document separation and transport device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic sheet separating and conveying apparatus for a facsimile machine, a copying machine, etc.
The present invention relates to an automatic sheet separating / conveying device capable of ensuring separation / conveyance performance regardless of the amount of stacked documents.

[0002]

2. Description of the Related Art In a document conveying device such as a facsimile machine or a copying machine, it is necessary to surely separate and convey the stacked documents (paper) one by one, and various mechanisms have been considered. A separation roller and a separation pad having a large friction coefficient are provided so as to face the separation roller, and a sheet in contact with the separation roller is conveyed by rotation of the separation roller, and a sheet in contact with the separation pad is conveyed. There is known a separation pad method in which sheets are separated and conveyed by suppressing the conveyance due to the large friction coefficient. When such a separation pad system is used, when a large number of sheets are inserted at once, the separation pad may not be separated one by one and the separation pad may rise. As a means for suppressing this phenomenon, Japanese Unexamined Patent Application Publication No. Hei 6
There is one described in Japanese Patent Publication No. 127721. There, the separation pad is pressed against the separation roller, and a regulation member (see 25 in FIG. 1 of the publication) is provided on the back surface of the pad upstream of the pressure contact of the separation pad to prevent the separation pad from floating. ing.

[0003]

The structure described in the above publication has a structure in which a conveying force is applied to an original only when the original enters the pressing contact portion between the separation pad and the separation roller. Documents are fed to part (pre-feed)
Since there is no means for making it possible, reliable pickup of the original cannot be guaranteed. For example, static electricity may be generated between the table portion on which the document is set and the document body, and if the conveyance path resistance increases, the document may not reach the pressure contact portion. Further, since the separating roller projects from the table portion on which the original is set, when a small number of originals or thin paper originals are set, there arises a problem that the leading end of the original comes into contact with the separating roller and is not conveyed. There was a possibility.

Further, when a large number of originals are set, there is no regulation such that the originals are pressed against the roller side, so that the upper original is conveyed after the previous page is conveyed by the resistance of the leading edge and the separation pad. There are also inconveniences such as not entering the pressure contact portion, and when the upper document hits the separation pad during setting, the lower document hits the roller and does not reach the pressure contact part. Normally, a material with a high friction coefficient such as rubber is used as the separation pad.However, after the final page is conveyed, the separation pad is pulled by the rotation of the separation roller, and a one-way clutch is used for the separation roller. Even if the original is conveyed by the roller of the next stage and the separation roller is rotated together, there is a disadvantage that the original pulls the separation pad. An object of the present invention is to ensure separation / conveyance performance regardless of the number of loaded originals, and to enable pre-feeding up to the number of sheets that can be set even when an original with a height exceeding the assumed loading capacity is set. At the same time, the assembling property of the components for that purpose is improved and the number of parts is reduced.

[0005]

In order to achieve the above object, the present invention provides a feed roller 4 and a separation pad 5 for separating and feeding out a document, a pad holder 14 for supporting the separation pad 5, and the above-mentioned. A pre-feed leaf spring 18 that enables pre-feed by press-contacting the feed roller on the document insertion opening side of the press-contact portion between the feed roller and the separation pad.
A pressing pad 16 for the separation pad, a guide plate 17 having a protrusion (L) at a position facing the center of the separation pad,
In addition to having the pressure plate 6, the interval between the presser 16 and the protrusion (L) of the guide plate 6 is slightly larger than the maximum document stacking height,
In addition, when the number of stacked documents of this height is set, the lower document can be pressed against the feed roller outside the protrusion of the guide plate by the pre-feed plate spring. Further, the pre-feed leaf spring 18 is characterized in that the pre-feed leaf spring 18 is shaped so as to be located closer to the conveyance path than the presser in the vicinity of the presser at the center in the conveying direction when the tip thereof is in pressure contact with the feed roller 4. Further, the width dimension of the protrusion (L) provided on the guide plate 17 is smaller than the width dimension of the presser. Further, the pre-feed leaf spring 18 is formed of an integrated resin or spring material and has a receiving portion (J) for the pressure plate and a spring portion (arm portion K) that comes into pressure contact with the feed roller, and also receives the pressure plate (J). ), The support shaft (C) of the pad holder is supported on the pressure plate 6 in a swingable state.

[0006]

When the originals are set, when the distance between the presser and the projections provided at the position facing the center of the separation pad of the guide plate is slightly larger than the maximum stacking height, and the number of stacked originals of this height is set. The pre-feed plate spring allows the lower document to be pressed against the feed roller on the outside of the protrusion, preventing an excessive number of documents from being set, and also ensuring that the pre-feed plate is set against the set document. It can be picked up with a spring. Also, when the tip of the pre-feed leaf spring is in pressure contact with the feed roller, the pre-feed leaf spring is located closer to the feed path than the foot in the vicinity of the presser in the center of the feeding direction, so that the number of originals set is large. Even if it becomes, it will be possible to reliably pre-feed. Furthermore, by making the width dimension of the protrusion provided at the position facing the center of the separation pad of the guide plate smaller than the presser foot, even if a large number of originals are pushed in and stuck in, the gap between the prefeed leaf spring and the It will not be pinched, and it will be possible to reliably feed out the lower document in order. In addition, the pre-feed leaf spring is formed of an integrated resin or spring material, and has a receiving portion for the pressure plate and a spring portion that is in pressure contact with the feed roller, and the support shaft of the pad holder can be swung by the receiving portion for the pressure plate. By supporting the pressure plate in this state, the assemblability is improved and the number of parts can be reduced.

[0007]

Next, one embodiment of the present invention will be described in detail with reference to FIGS. FIG. 1 is an overall schematic configuration diagram of the present invention. In the figure, 1 is a conveyance roller, 2 is a paper discharge roller, 3 is a roller opposite to these conveyance rollers, 4 is a feed roller (separation roller), 5 is a separation pad, 6 is a pressure plate, and 7 and 8 are respectively first. And a second sensor, 9
Is a mirror, 10 is a lens, 11 is a photoelectric conversion element such as a CCD, 12 is a light source, and 13 is a paper discharge tray. FIG. 1 shows a schematic configuration of a separation pad type separation unit including a feed roller 4 and a separation pad 5, and a conveyance unit including a conveyance roller 1, a paper discharge roller 2, a counter roller 3, and the like.
The document separating / conveying device is roughly divided into feed rollers 4
And a separation unit including a separation pad 5, and a conveyance unit including a conveyance roller 1, a paper discharge roller 2, a counter roller 3, and the like. In the separating section, the coefficient of friction between the feed roller 4 and the original is made larger than the coefficient of friction between the separating pad 5 and the original, so that the originals are separated one by one from the lower side and sequentially fed out. On the other hand, in the transport section, the documents separated in the separating section and sequentially fed out are transported by the transport roller 1, the discharge roller 2,
Necessary conveyance is performed by the opposing roller 3 and the like. That is, the original fed out from the separating portion is conveyed to the reading portion by the conveying roller 1 at a predetermined speed, and the photoelectric conversion element 11 is controlled in synchronization with the conveying speed so that the image on the original is an electrical signal. Converted to and read. After passing through the reading section, the original document is conveyed to the sheet ejection tray 13 by the sheet ejection roller 2 and ejected.

Each of these rollers is driven by a drive system such as a motor and a gear (not shown). The position of the document is detected by a first sensor 7 that detects that the document has reached the feed roller 4 and a second sensor 8 that detects that the document has reached the reading section. A control unit (not shown) drives each roller based on the information from the first sensor 7 and the second sensor 8 and controls the reading optical system at a timing synchronized with this.

FIG. 2 is a schematic side view of the separating portion which is a feature of the present invention. In the figure, 14 is a pad holder, 1
Reference numeral 5 is a spring (coil spring), 16 is a retainer, 17 is a guide plate, 18 is a pre-feed leaf spring, and the same parts as those in FIG. 1 are designated by the same reference numerals. Figure 3
Pressure plate 6, pad holder 14, separation pad 5, presser foot 16,
It is a figure which shows the state which looked at the assembly structure of the pre-feed leaf spring 18 from the lower side. As shown in FIG. 3, the separation pad 5
Is positioned on the pad holder 14 by the hole (A) of the separation pad 5 and the protrusion (B) of the pad holder 14, and the presser 16
It is fixed to the pad holder 14 with. The fixing method in this case includes a method in which the presser 16 and the pad holder 14 are formed by using an elastic member such as resin, and the elastic force is used to fit the two together.
A fixing method such as screwing or adhesion may be used.

By forming the presser 16 with a material having a high slidability such as resin, it is possible to reduce the contact resistance to the original document in this portion. The pad holder 14 has a support shaft (C) at both ends thereof, and by being incorporated in a U-shaped groove (D) provided in the pressure plate 6, the pad holder 14 is swingably attached to the pressure plate 6. The end of the pad holder 14 opposite to the support shaft (C) is inserted into the opening (E) of the pressure plate 6. The pad holder 14 is provided so that it does not come into contact with the pressure plate 6 in the original conveyance state, and that the pressure plate 6 is at the bottom dead center (stop position) of the pad holder 14 during maintenance such as jam clearance and roller cleaning. .

A protrusion (F) is provided at the center of the support shaft (C) on both sides of the pad holder 14, and a protrusion (F) is provided between the protrusion (F) and the hooking portion (G) provided on the pressure plate 6. The separation pad 5 is brought into pressure contact with the feed roller 4 by applying a spring 15 as a coil spring. A flat surface portion (H) is provided on both sides of the mounting position of the pad holder 14 of the pressure plate 6, and the flat feed portion (H) is used in this flat surface portion (H).
The seat portion (J) of the pad holder 14 is received by the seat portion (J) of the pre-feed leaf spring 18 while receiving the seat portion (J) of 8.
Receive. The pre-feed leaf spring 18 is made of an elastic material such as a spring material or resin, has two arm portions (K) near both sides of the separation pad 5, and the tip of the arm is pressed against the feed roller 4. Composed.

As shown in FIG. 2, the pressure contact of the pre-feed leaf spring 18 to the feed roller 4 is located closer to the document insertion opening side than the pressure contact of the separation pad 5 and the feed roller 4, and the document is separated from the separation pad. It is possible to pre-feed to the pressure contact of No. 5. In addition, the plate spring is shaped so that it is positioned below the presser 16 at a substantially central portion (near the presser 16) of the two arm portions (K) of the pre-feed plate spring 18.
Therefore, even if the number of loaded sheets changes, the pre-feed leaf spring 18
Thus, the original can be pressed against the feed roller 4.

Further, as shown in FIG. 2, a protrusion (L) is provided at the entrance of the document guide plate 17 to the feed roller 4. At this time, the interval between the protrusion (L) of the document guide portion and the presser 16 of the separation pad is set to be slightly larger than the maximum stacking height of documents. The width of the protrusion (L) is set to be shorter than the width of the separation pad 5 or the presser foot 16, and when the number of originals exceeds the expected value, the distance between the presser foot 16 and the protrusion (L) is set. Since the stacking height of the originals is large, the user perceives that the number of set sheets is excessive. However, even in this state, since there is no protrusion in the portion facing the pre-feed leaf spring 18, the lower original is pressed against the feed roller 4. Can be transported. Document guide plate 17
Since the distance between the protrusion (L) and the presser 16 of the separation pad is set slightly larger than the maximum stacking height of the originals, it is possible to prevent the number of originals that greatly exceed the maximum stacking height from being set. You can Further, the set original can be picked up by the pre-feed leaf spring 18. In addition, since the width of the protrusion (L) of the document guide plate 17 is made smaller than the width of the pressing pad 16 of the separation pad, even if a large number of documents are stuck in and pushed in, the pre-feed plate spring 18 and It is not extremely pinched, and even in such a case, it is possible to feed the document from the lower document in order.

[0014]

As described above, according to the present invention, the separation and conveyance can be performed reliably regardless of the number of stacked originals, and the original can be set even when the height of the original exceeds the assumed stacking capacity. It is possible to pre-feed up to the maximum number of sheets, and the support shaft of the swing center of the pad holder is supported by the pre-feed leaf spring, which improves the assemblability and greatly reduces the number of parts. It will be possible.

[Brief description of drawings]

FIG. 1 is an overall schematic configuration diagram of the present invention.

FIG. 2 is a schematic side view of a separating unit which is a feature of the present invention.

FIG. 3 is a diagram showing a state in which the assembling structure of the separating unit according to the present invention is viewed from below.

[Explanation of symbols]

1: transport roller, 2: paper discharge roller, 3: facing roller,
4: Feed roller (separation roller), 5: Separation pad,
6: pressure plate, 7: first sensor, 8: second sensor, 9:
Mirror, 10: Lens, 11: Photoelectric conversion element, 12: Light source, 13: Paper ejection tray, 14: Pad holder, 15: Spring (coil spring), 16: Presser, 17: Guide plate, 18: Pre-feed leaf spring

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) B65H 3/66 B65H 3/06 B65H 3/06 320 B65H 3/52 330 H04N 1/00 108

Claims (4)

(57) [Claims] 1. An automatic document separating / conveying device of a separation pad system for separating and conveying a plurality of stacked documents one by one, and a feed roller and a separation pad for separating and feeding the documents, and a separation pad. A pad holder that supports, a pre-feed leaf spring that presses the feed roller on the side of the document insertion port from the pressure contact portion of the feed roller and the separation pad to enable pre-feeding, the pressing of the separation pad, and the center of the separation pad. In addition to having a guide plate having protrusions at opposing positions and a pressure plate, the distance between the presser and the protrusions of the guide plate is slightly larger than the maximum stacking height of originals, and the number of originals stacked at this height is small. When set, the lower feed can be pressed against the feed roller outside the projection of the guide plate by the pre-feed leaf spring. Automatic document separating and feeding device. 2. The automatic original separating and conveying apparatus according to claim 1, wherein the pre-feed leaf spring is located closer to the conveying path than the presser in the vicinity of the presser at the center in the conveying direction when the tip of the pre-feeding plate spring is in pressure contact with the feed roller. An automatic document separating / conveying device having a shape as described above. 3. The automatic document separating / conveying apparatus according to claim 1, wherein a width of a protrusion provided on the guide plate is smaller than a width of the presser. 4. The automatic document separating / conveying apparatus according to claim 1, wherein the pre-feed leaf spring is formed of an integrated resin or spring material, and is formed in a receiving portion for the pressure plate and a feed roller. An automatic document separating / conveying apparatus, which has a spring portion which is in pressure contact with the support shaft of the pad holder and is swingably supported by the pressure plate by a receiving portion for the pressure plate.