JPH0318546A - Automatic original paper feeding device - Google Patents

Abstract

PURPOSE:To obtain the uniform press contact force of a following roller for a prime mover roller by arranging the following roller inside the top part of a base member so that the upper surface of the following roller projects from a hole formed on the top part and energizing the shaft of the following roller upwardly by a leaf spring fixed onto the back surface of an inclined surface on the top part. CONSTITUTION:In a discharge roller part, a shaft 23 having a plurality of following rollers 21 is energized upwardly by a leaf spring 25 fixed onto the back surface of an inclined surface 22a on the top part of a base member 22. Therefore, the pressing force (press contact force) for a prime mover roller 12 of the following roller 22 whose upper surface projects from a hole formed on the top part is made uniform, and the transport of an original D is stabilized, and the generation of skew and jam can be prevented. Further, in a transport roller part immediately before a read-out part, the following roller is separated from an original roller if necessary, and the jam is eliminated.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is an automatic document feeder installed in a document image reading device, which separates documents one by one and supplies them to a reading unit, and also discharges scanned documents. This is related to the paper ejection device (usually called ADF). (Prior Art) First, Fig. 4 shows the external appearance of an example of an ADF to which the present invention can be applied. its base member,
4 is a document table, 5 is an upper cover, and 6a and 6b are left and right covers. A conventional ADF is structured as shown in Figure 5. 7 is the original D placed on the original table 4
9.10 The calling roller that sends the material to the pair of separating rollers 8.
1 is a conveying roller that conveys the original separated one by one by the separation roller 8 along a guide member, and 11 is an original glass provided in the reading device main body 1. When the original reaches the position indicated by arrow R, it is read (not shown) The image is read by an optical system (hereinafter, R will be referred to as a reading section). Reference numeral 12 denotes a moving drive roller for ejecting the scanned original, and reference numeral 13 denotes a driven roller for ejection that comes into pressure contact with the driving roller 12. The distal end is lifted by the provided guide scale 14 and conveyed along the guide plate l5, and the discharge port-ra (12, 13)
It is discharged by l6 consists of a part of the base member,
This is a stacker section that stores ejected documents.

(Problem to be Solved by the Invention) However, in this conventional example, as shown in FIG. A plurality of the plate springs 17 are arranged through the bending angle and dimensional error of the leaf spring 17, which causes variations in the pressing force on the driving roller l2.
Therefore, the frictional force between each roller changed, causing uneven document conveyance. The original must be fed at a constant speed and parallel to the reading section I, but due to uneven transport, the original may gradually become skewed, making it impossible to read it accurately or causing paper jams. There was a problem. Furthermore, since the support portion 17a of the driven roller 13 must extend beyond the outer diameter of the roller, the support portion 17a must extend beyond the outer diameter of the roller.
The length between 7a and the fixed part of the leaf spring 17, that is, the length of the arm, becomes short within a limited space, making it difficult to adjust the spring pressure. There were also problems such as the overall thickness becoming thicker.

Furthermore, if a jam occurs in the portion of the conveyance roller 10 disposed immediately before the reading section R, the conveyance roller 10 is moved to the drive roller]. Since the positions of both the Oa side and the driven roller 10b side are fixed, it is very difficult to eliminate jams.

The present invention solves the above-mentioned problems of the prior art, and the suppressing force of the driven roller against the driving roller for ejection becomes uniform, so that the document is conveyed correctly, and therefore, the occurrence of jams is reduced. To provide an ADF that can easily eliminate a jam even if it occurs.

(Means for Solving the Problems) In order to achieve the above object, the ADF of the present invention includes a driving roller for discharging a scanned document, a driven roller that presses against the driving roller, and a driven roller for discharging the scanned document. The driven roller includes a portion having an inclined surface and a chevron-shaped cross section for guiding up to the roller, and a base member having a stacker portion for ejected documents, and the driven roller has a plurality of rollers provided at a predetermined interval on one shaft. The upper surface of the roller is arranged inside the chevron-shaped part so that it protrudes from a hole formed in the chevron-shaped part of the base member, and the shaft of the driven roller is attached upward by a leaf spring fixed to the back surface of the inclined surface. The configuration is such that it is supported.

In addition, the guide member facing the inclined surface of the base member in the document ejecting section is rotatable around the bearing of the driving roller, and the guide member is configured to maintain a constant distance from the document glass in the reading section. A structure with means in place.

Furthermore, the driven roller unit includes a driving roller for document conveyance disposed immediately in front of the reading section, and a driven roller that is in pressure contact with the driving roller, and the driven roller unit includes a main bracket having a document conveying guide section, An auxiliary bracket is provided to be rotatable around a first shaft supported by a pair of bearings protruding from the main bracket, and a second shaft is arranged at a predetermined interval on a second shaft held by the auxiliary bracket. a plurality of driven rollers, a spring provided between the main bracket and the auxiliary bracket, and urging the auxiliary bracket so that the driven rollers come into pressure contact with the driving roller; and a lever that separates the driven roller from the driving roller accordingly.

(Function) According to this configuration, first, in the discharge section, the document guide surface is integrally formed with the base member, so there is no need for a guide plate as a separate part, and the plurality of driven rollers are connected to one Since the shaft is provided on a shaft and the shaft is urged upward by a leaf spring, the pressing force of the driven roller against the driving roller becomes uniform, and skewing can be prevented.

In addition, in the conveying roller section immediately before the reading section, the driven roller can be separated from the driving roller as necessary, making it very easy to eliminate jams.

(Example) Hereinafter, embodiments will be described in detail with reference to the drawings.

FIG. 1 shows an ADF according to an embodiment of the present invention.
Items with the same symbols as in Figure 5 indicate the same items, and 2
1 is a driven roller that comes into pressure contact with the driving roller 12; 22 is a portion that has a chevron-shaped cross section and has an inclined surface 22a that guides the document whose image has been read at the reading position indicated by the arrow R to the driving roller 12 and the driven roller 21; and a stacker section 22b for accommodating the discharged original document D'. As shown in FIG. 3, the driven roller 2l has a plurality of rollers arranged at predetermined intervals on l shafts 23, and the upper surface of the roller protrudes from a hole 24 formed in the chevron-shaped portion of the base member. It is placed inside the chevron part. Further, the shaft 23 of the driven roller is, as shown in FIG. 2(a),
It is biased upward by a leaf spring 25 fixed to the back surface of the inclined surface 22a. Further, the shaft 23 of the driven roller
As shown in Figure (b), a groove 26 formed in the base member 22
The lateral displacement is regulated by In addition, 27 is A
A pad 28 that presses down the original placed on the original glass 11 when the DF is not used is a white sheet extending from the lower surface of the pad 27 to the guide scale 14.

Here, the guide member 30 facing the inclined surface 22a of the base member 22 is a thin plate having spring properties, and is rotatable around a bearing of the shaft 19 of the driving roller 12 for ejection. That is, as shown in FIG. 7, by fitting the notch 30a provided in the guide member 30 inside the side plate 3l of the device and further inserting the bearing 32 from the end of the shaft 19, the guide member 30 is It is attached so that it can rotate freely. On the other hand, in the vicinity of the reading section R of the guide member 30, the distance from the original glass 11 must be kept constant at 0.3 to 0.5 m, so as shown in FIG. Spacers 33a, 33b, 33c, etc. are provided.
The spacer 33a in (a) is formed by bending the end of the guide member.
33b in (b) is a string taken out, and 33c in (C) is a separate member attached. Furthermore, in order to maintain a constant distance from the original glass l1 using these spacers, as shown in FIG. 9(a),
, As shown in (b), a coil spring 34a or a leaf spring 34b provided on the side plate 3l, or as shown in (c), the spring of the guide member 30 itself is used to extend from both ends of the flat part 30b. The end portion 34c of the protruding portion is engaged with a hole formed in the side plate 31 to press down the spacer portion.

Next, the operation of this embodiment will be explained. A plurality of originals D set on the original table 4 are sent to a separation roller 8 by a calling roller 7. Here, the original is separated into sheets one by one, and each separated sheet is sent to the reading section R by transport rollers 9 and 10, where it is sequentially read. The leading edge of the document is lifted by the guide scale l4, climbs along the inclined surface 22a and the guide member 30, and is discharged onto the stacker section 22b by the driving roller l2 and the driven roller 2l.

In this embodiment configured as described above, (1) Since the driven roller 21 has a structure in which a plurality of rollers are provided on one shaft 23, there is no variation in the suppressing load of the individual rollers. As a result, the document conveyance force becomes uniform, preventing skew from occurring. In addition, the leaf spring 25
Since the structure is such that the shaft 23 is directly pushed up, the length of the arm of the leaf spring 25 can be maximized even in a limited space, and the spring pressure can be easily adjusted. (2) Slanted surface 22a that guides the original to a part of the base member
Since it is integrally formed, there is no need for a guide plate as a separate part, and since the leaf spring 25 is structured to directly push up the shaft 23, there is no need for bearings, etc. Since the number of parts can be reduced, the number of parts can be reduced, and costs can be significantly reduced.

(3) The guide member 30 has spring properties, and the reading portion R
Since it is possible to maintain a constant gap between the document glass and the document glass in the vicinity, it is possible to absorb variations in the dimensional accuracy and installation accuracy of components, improve paper passing performance, and prevent the occurrence of skews and jams. Figures 10 to 12 show other embodiments of the discharge driven roller portion. Here, two driven rollers 2l are attached to one shaft 23a and two ob, respectively.
, 23b are inserted into 138 formed in the pace member 22, and are pressed by a bottom plate 37 via a coil spring 36. With such a structure, the base member 2
This is advantageous in cases where warpage occurs during molding of the rollers 2, etc., as it provides a better balance of left and right pressure than the configuration shown in FIG. 3, in which all the driven rollers 2l are attached to one shaft. Next, conveyance rollers 10a and 10b immediately in front of the reading section R
If a jam occurs between the two rollers, it is extremely difficult to remove the jam because the positions of both rollers are fixed. In the present invention, the driven roller lOb side is formed into a unit, and the driven roller unit is manually rotated around the shaft as necessary to separate the driven roller 10b from the driving roller 10a, making it extremely easy to remove jams. I have to.

FIG. 13 shows an example thereof, in which 40 is a driven roller unit, and as shown in detail in FIG. 14,
a main bracket 41 having a document conveyance guide section 41a;
An auxiliary bracket 44 is rotatably provided around a first shaft 43 supported by a pair of bearings 42 protruding from the main bracket 41, and a second shaft 45 is held by the auxiliary bracket 44. A plurality of driven rollers lOb arranged at predetermined intervals, a main bracket 41 and an auxiliary bracket 4
4, and the driven roller lOb is provided between the driving roller 1
It consists of a spring 46 that biases the auxiliary bracket 44 so as to come into pressure contact with the auxiliary bracket 44, and a lever 47 that is provided at at least one location on the auxiliary bracket 44 and that separates the driven roller from the driving roller as necessary. The main bracket 41 has both ends connected to device side plates (not shown).
It is fixed with screw 48. Although the pair of bearing portions 42 are formed here by cutting and bending from the main bracket 41, separate members may be attached by spot welding or screwing. Both end rising portions 44a of the auxiliary bracket 44 are located inside this bearing portion 42, and the first shaft 43 is inserted therethrough. The auxiliary bracket 44 is rotatable about its shaft 43. U-shaped notches 49 are provided in the rising portions 44a at both ends of the auxiliary bracket 44.
9, a second shaft 45 through which a plurality of driven rollers 10b are inserted;
are inserted at both ends. The driven rollers 10b are located in cutouts 44b formed in the auxiliary bracket 44, and their lateral movement is restricted. Also, driven roller 1
0b partially protrudes from a hole 50 provided in the document conveyance guide portion 41a of the main bracket 41, and comes into pressure contact with the driving roller lOa. The pressing force P is obtained by the biasing force of a spring 46 provided between the main bracket 41 and the auxiliary bracket 44. In this embodiment configured in this way, the driving roller 10a
If only the positioning of the main bracket 4l is performed with high precision, the pressing force of the driven roller 10b against the driving roller 10a will be substantially uniform, and assembly will be easy.

Furthermore, the driven roller 10b can be assembled to the auxiliary bracket 44 by simply inserting both ends of the shaft 45 into the U-shaped notch 49. In particular, since the auxiliary bracket 44 that holds the driven roller 10b is rotatable about the shaft 43 relative to the main bracket 4l, if a paper jam occurs between the driving roller 10a and the driven roller 10b, By operating the lever 47 and rotating the auxiliary bracket 44, the driven roller lOb can be separated from the driving roller 10a, and jams can be easily eliminated.

(Effects of the Invention) As explained above, according to the present invention, the pressure contact force of the driven roller against the driving roller becomes uniform in the ejection roller section, the document is stably conveyed, and skews and jams do not occur. Prevented. In addition, in the conveyance roller section just before the reading section, even if a jam occurs, the rollers are kept apart.
Jam can be easily removed. Furthermore, it has various effects such as overall improvement in assembly workability, reduction in the number of parts, and cost reduction.

[Brief explanation of the drawing]

Figure ↓ is a configuration diagram of an ADF according to an embodiment of the present invention, Figure 2 is a sectional view of the shaft holding part of the driven roller in the discharge port-R section, and Figure 3 is a perspective view of the driven roller part. , FIG. 4 is a diagram showing the appearance of an ADF to which the present invention can be applied, and FIG. 5 is a diagram showing the appearance of an ADF to which the present invention can be applied.
A diagram of the structure of a conventional ADF, FIG. 6 is a perspective view of the driven roller, FIG. 7 is a configuration diagram of the attachment mechanism of the guide member in the ejection section, and FIG. 8 is the vicinity of the reading section of the guide member. FIG. 9 is a configuration diagram of the holding mechanism near the reading section of the guide member, FIGS. 10 to 12 are configuration diagrams of other embodiments of the ejection section, and FIG. FIG. 14 is a sectional view mainly showing the driven roller unit of the conveyance roller immediately before the reading section of the ADF of the invention, and is an exploded perspective view of the driven roller unit.

Claims (3)

[Claims] (1) In an automatic document feeder and ejector that is installed in a document image reading device and separates documents one by one and supplies them to the reading section and also discharges the scanned documents, there is a drive roller that discharges the scanned documents and a drive roller that discharges the scanned documents. The base member includes a driven roller that comes into pressure contact with the driving roller, a base member that has an inclined surface that guides the read original to the driving roller and the driven roller, and has a chevron-shaped cross section, and a stacker section for the ejected original. The driven roller has a plurality of rollers arranged at predetermined intervals around one shaft, and is arranged inside the chevron-shaped portion so that the upper surface of the roller protrudes from a hole formed in the chevron-shaped portion of the base member, and An automatic document feed/discharge device characterized in that the shaft is biased upward by a leaf spring fixed to the back surface of the inclined surface. (2) The guide member facing the inclined surface of the base member is rotatable around the bearing of the driving roller, and means is provided in the reading section for maintaining a constant distance from the document glass. The automatic document feeder and ejector according to claim 1, characterized in that the automatic document feeder and ejector includes: (3) In an automatic document feeder/discharge device installed in a document reading device, which separates a plurality of documents one by one and supplies them to a reading section, a driving roller for document conveyance disposed immediately before the reading section; a driven roller unit having a driven roller in pressure contact with the driving roller; the driven roller unit includes a main bracket having a document conveyance guide section; and a first roller supported by a pair of bearing sections protruding from the main bracket. an auxiliary bracket rotatably provided around the axis of the auxiliary bracket; and a second bracket held by the auxiliary bracket.
a plurality of driven rollers arranged at predetermined intervals on the axis of the main bracket, and a spring provided between the main bracket and the auxiliary bracket to urge the auxiliary bracket so that the driven rollers come into pressure contact with the driving roller; An automatic document feeder and ejector comprising: a lever provided at at least one location on the auxiliary bracket for separating the driven roller from the driving roller as necessary.