JP2942143B2 - Automatic paper feeder - 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 paper feeder for an information processing apparatus using a sheet medium such as an image reading apparatus and a facsimile apparatus, and more particularly to a housing structure thereof and a roller shaft to the housing. And a support structure for mechanical parts.

[0002]

2. Description of the Related Art In an information processing apparatus provided with an automatic paper feeder, a paper path is usually formed so as to cross the apparatus. Further, the housing of the apparatus needs to be structured so that the paper can be easily taken out from the paper passage when a paper jam occurs. Therefore, the housing of the automatic paper feeder has a structure that is vertically divided into two parts with the paper path interposed therebetween, and the upper housing is pivotally supported on the lower housing by a horizontal fulcrum axis, and the upper housing is opened upward. It is common to have a structure in which a paper passage is sometimes opened.

[0003] A plurality of rollers for feeding paper are erected on the housing of the automatic paper feeder. These include a paper feed roller, a feed roller, and a paper discharge roller. A driving device for these rollers is arranged on the side of the paper path in the housing. Further, in order to prevent the paper from waving (lifting) or skew (skew) in the paper passage, a paper guide is arranged so as to vertically sandwich the paper in the paper passage.

FIGS. 3 and 4 show an example of the structure of an image reading apparatus provided with an automatic paper feeder having such a structure. The illustrated apparatus is capable of reading both an original (fixed original) placed on a transparent platen and an original (transferred original) transported by an automatic paper feeder. A transfer original reading unit A and a stationary original reading unit B are provided on the upper surface. A glass plate 52 is fixed to the upper surface of the main body 51, and a carrier 53 running along the lower surface of the glass plate is provided. An optical unit for reading a document is mounted in the carrier 53. On the stationary document reading unit B side, a pressing cover 54 for pressing a document fixed on the glass plate 52 is provided to be openable and closable.

Documents read by the transport document reading unit A are:
It is fed into the automatic paper feeder 56 from a shooter 55 foldably provided above the presser cover 54, and
2 and is discharged to the stacker 57. At this time, the carrier 53 is stationary below the automatic paper feeder 56, and the optical unit of the carrier 53 reads a document traveling along the upper surface of the glass plate 52.

A paper feed roller 35, a first feed roller 5, and a second feed roller 6 having a function as a paper discharge roller are arranged along the paper path C in the housing of the automatic paper feeder 56. . The housing of the automatic paper feeder 56 is divided into a lower frame 31 and an upper frame 1 with a paper path C interposed therebetween. The paper feed roller 35 is supported by the lower frame 31, and a separation pad 28 facing the paper feed roller across the paper path is mounted on the upper frame 1. The first and second feed rollers 5, 6 include a driving roller 5a,
6a and driven rollers 5b and 6b rotating in contact therewith feed the paper sandwiched between them. The driving rollers 5a and 6a are supported by the upper frame 1, and the driven rollers 5b and 6b are supported by the lower frame 31. Have been.

The upper frame 1 is pivotally supported on a lower frame 31 at a left end portion in FIG. 4 by a fulcrum shaft 8 (see FIG. 1) perpendicular to the plane of the drawing. By turning upward, the paper path C is opened.

[0008]

The housing of this type of automatic paper feeder is usually composed of a metal frame made of sheet metal, a paper guide made of a thin plate, and an outer cover made of synthetic resin. The paper feeding roller, its driving mechanism, a paper guide forming a paper path, and the like are mounted on a metal frame, and an outer cover is attached to the outside of the metal frame.

On the other hand, with the widespread use of information processing devices,
It is strongly demanded that the cost of the device be reduced and that the operation be assured. At the same time, it is required that the device be made smaller and the appearance be excellent in design.

SUMMARY OF THE INVENTION An object of the present invention is to provide an automatic sheet feeder having a better cost-performance ratio, and to reduce the number of parts constituting a housing without deteriorating the appearance, thereby reducing the number of man-hours for manufacturing the apparatus. To avoid lowering the smoothness and accuracy of operation due to thermal expansion of parts, etc.
It is a specific object of the present invention to easily assemble mechanical parts such as rollers on a housing and to ensure that paper is fed and guided reliably and accurately.

[0011]

The automatic paper feeder according to the present invention has a paper path C crossing the apparatus, and a fixed lower frame 31 and a releasable upper frame 1 sandwiching the paper path.
And a structure in which the paper path C is opened when the upper frame 1 is opened. Upper and lower frames 1, 3
Reference numeral 1 denotes an injection-molded product made of a synthetic resin such as polycarbonate or ABS, on which the paper guide surfaces 2, 32 are integrally formed, and the roller shafts of the paper feed roller devices 5, 6, 35 are supported by shafts. Have been.

A side wall 37 of either the upper frame 1 or the lower frame 31 (the lower frame in the embodiment) on both sides of the paper path has a double structure including an inner plate 38 and an outer plate 39, The other (the upper frame in the embodiment) side wall 7 is located inside the one side wall 37. The roller shafts of the paper feed roller devices 5, 6, and 35 are connected to one of the above-mentioned frames.
Either Jikuka inside plate 38 of the side wall of the over-time, or are Jikuka on the side wall 7 of the other frame.

The roller shaft is connected to the bearing 2 fitted in the holes 3, 4, 33 provided in the inner plate 38 or the other side wall 7.
One end of each of the third and fourth shafts is axially immovable and the other end is axially movable.

A guide surface for guiding the lower surface of the sheet can be formed integrally with the lower frame 31 by a resiliently deflectable plate-like upper plate 36 which integrally connects the side walls 37 on both sides of the lower frame 31. On the lower side of the upper surface plate, reinforcing ribs 41 in the sheet feeding direction orthogonal to the guide surface are provided in a comb-like shape to ensure the accuracy of the shape of the sheet passage in the sheet feeding direction.

The upper frame 1 has an upper plate 10 forming the outer top plate of the apparatus. The upper plate is formed in a plate shape which can be elastically bent in the sheet width direction, and a reinforcing rib 11 in a sheet feeding direction orthogonal to a guide surface of the sheet is integrally formed in a comb-like shape below the upper surface plate. Guides the upper surface of the paper passing through the paper path. In this case, if necessary
Flip provided paper guides elongated strip-shaped metal plate paper guide 12 in the sheet width direction by, they are effective to more reliably prevent such bending of the corners of the sheet. The paper guide 12, one side wall of the upper frame and the longitudinal end 7
Fixed to and secured to the other end on the other side wall 7 of the upper frame so as to be relatively loose in its longitudinal direction, and attaching the central portion in a state that was backed up at the tip side of the comb teeth-shaped reinforcing ribs 11.

When the upper and lower frames 1 and 31 are provided with an upper plate which can be elastically bent in the paper width direction, the upper and lower frames 1 and 31 are opposed to each other across the paper passage.
Paper having a driving roller 5a and a driven roller 5b facing each other
The driven roller 5b of the feed roller device 5 is pivotally supported at the center of the upper plate 36, and the driven roller 5b is pressed against the opposing drive roller 5a by the elastic restoring force caused by the bending of the upper plate to pinch the sheet. Structure.

When the upper and lower frames 1 and 31 are provided with upper plates 10 and 36 which can be elastically bent in the sheet width direction, the side wall 37 of one frame 31 extends over the sheet guide surface 32 and is placed on the other frame 1 side. A pair of a fulcrum shaft 8 and a pivot hole 40 for pivotally supporting the upper frame 1 is formed on the inner plate 38 and the side wall 7 of the other frame 1 so as to be integrally formed with the frames 1 and 31 respectively; Top plates 10 and 3 of both frames
The upper frame 1 can be pivotally connected to the lower frame 31 so that the upper frame 1 can be freely opened and closed by engaging the fulcrum shaft 8 with the pivot hole 40 by utilizing the elastic bending of FIG.

The synthetic resin of the upper and lower frames 1 and 31 is a synthetic resin having the same coefficient of thermal expansion as the synthetic resin frame 51 of the information processing apparatus to which the automatic sheet feeder is mounted.
It is possible to avoid occurrence of an error in the positional accuracy of the frame due to a difference in thermal expansion between the frames.

[0019]

According to the above configuration, the metal frame of the automatic sheet feeder is eliminated, and the number of components constituting the housing can be reduced. By eliminating the need for a metal frame having a complicated manufacturing process, the number of manufacturing steps for parts can be significantly reduced. Also, there is no bending of the guide or twisting of the sliding portion due to a difference in thermal expansion between the metal mechanical parts or the paper guide and the synthetic resin frames 1 and 31, and an accurate paper feeding operation can be guaranteed. .

Also, one side wall 3 of the upper and lower frames 1 and 31
7 has a double structure, and the other side wall 7 is located inside, so that the mounting ends of the mechanical components such as the paper feed rollers 5, 6, and 35 are not exposed to the outside of the frame without increasing the number of assembling steps. Can be structured.

The side walls 7, 37 of the upper and lower frames 1, 31 are integrally connected by plate-like upper plates 10, 36 which can be elastically bent in the sheet width direction, and reinforcing ribs 41 are provided below the upper plates 10, 36. The structure in which the paper is guided by the top plate 36 and the leading edge of the reinforcing rib 11 enables the paper guide to be integrally formed with the frame without complicating the molding die of the frame, and for the stable feeding of the paper. The shape accuracy of the guide in the important paper feeding direction can be guaranteed.

When an elongated strip-shaped paper guide 12 made of metal plate is attached to the main part of the paper guide formed by the reinforcing rib 11 in the above-described structure, the guide of the paper at the required portion of the paper path is more reliably performed. Paper guide 12
And the assembling work are simplified, and bending deformation due to a difference in thermal expansion between the synthetic resin frame and the metal paper guide can be prevented.

Further, since the driven roller 5b of the feed roller is pivotally supported at the center of the upper plate 36 which can be elastically flexed, a spring for applying a sheet clamping force to the feed roller can be omitted, and the number of parts can be reduced. I can do it.

[0024]

1 to 3 show an embodiment of the present invention. As shown in FIGS. 1 and 2, the housing of the automatic paper feeder is divided into an upper frame 1 and a lower frame 31 with a paper path as a boundary, and both frames 1 and 31 are made of synthetic resin. . The upper and lower frames 1 and 31 are injection molded products, and the paper guide surfaces 2 and 32 are integrally formed. Holes 3, 4, 3 are provided in the side walls of the upper and lower frames 1, 31.
The bearings 23 and 44 are fitted in these holes, and the roller shafts of the paper feed roller devices 5, 6, and 35 are supported by these bearings.

The side wall 37 of the lower frame 31 is
And an outer plate 39. The side wall 37
It projects above the upper surface of the lower frame, which serves as a paper guide surface, and has a pivot hole 40 for pivotally supporting the upper frame 1 in its inner plate 38. The upper frame 1 includes an upper plate 7 that fits inside the inner plate 38 of the lower frame,
A fulcrum shaft 8 serving as an open / close center of the upper frame is integrally provided on the upper plate 7 so as to protrude outward. The fulcrum shaft 8 can be fitted into the fitting hole 40 by elastic bending of the upper plate 7 and the inner plate 38 made of synthetic resin.

In the embodiment shown, the inner plate 38 of the lower frame is provided.
The upper surface of the space formed between the upper frame 1 and the outer plate 39 is closed by a flange 9 projecting laterally from the upper end of the upper frame 1.

The side walls 37 on both sides of the lower frame 31 are
In the portion on the paper insertion side, the paper is integrally connected by an upper surface plate 36 obliquely inclined in the paper transport direction, and the upper surface plate forms a paper guide surface 32 serving as a lower surface of the paper path. Top plate 36
On the lower side, a reinforcing rib 41 in a direction parallel to the side wall 37 is integrally formed in a comb shape. Due to the presence of the reinforcing ribs 41, the upper plate 36 can be elastically bent in the paper width direction, but has high rigidity and high shape accuracy in the paper feeding direction. The driven roller 5b of the first feed roller, which will be described later,
Is pressed against the drive roller 5a by the elastic bending in the paper width direction.

The upper plates 7 on both sides of the upper frame 1 are integrally connected by an upper plate 10 serving as an upper surface of a casing of the automatic sheet feeder. Below the upper plate 10, reinforcement in a direction parallel to the upper plate 7 is provided. The rib 11 is provided in a comb shape. The tip sides of the plurality of parallel reinforcing ribs 11 form the paper guide surface 2 above the paper path.

The paper guide surface 2 above the paper path is generally formed by the tip side of the comb-shaped reinforcing rib 11, but near the feed rollers 5 and 6, the paper end is bent. In order to reliably prevent such a situation, a strip-shaped metal sheet paper guide 12 is provided. Both ends of the paper guide 12 are held by the upper plate 7 of the upper frame, and the paper guide 12 is backed up by the distal end side of the comb-shaped reinforcing rib 11 to prevent the central portion from bending and deforming.

The metal sheet paper guide 12 has one end in the longitudinal direction fastened and fixed to the distal end side of the upper plate 7 on the side thereof by a screw 15. A tongue piece 14 protrudes from the other end of the paper guide 12, and a slit 13 into which the tongue piece 14 is inserted is formed in the upper plate 7 on that side. Slit 13
The tongue piece 14 and the tongue piece 14 are fitted together with a play gap that is slightly movable in the longitudinal direction (paper width direction) of the paper guide 12, and the metal paper guide 12 and the upper frame 1 made of synthetic resin. Is absorbed by the relative movement of the slit 13 and the tongue piece 14, thereby preventing the metal paper guide 12 from being bent and deformed due to the difference in thermal expansion.

In the apparatus of the illustrated embodiment, the paper guide 12 is provided at a portion where the first feed roller 5 and the second feed roller 6 are mounted, and the paper guide 12 is provided with an opening 16 through which the feed roller projects. Have been. A part of the comb-shaped reinforcing rib 11 is cut out in the upper frame, and a motor 17 for driving the feed roller is accommodated in the space. Therefore, a cover 18 that covers the motor housing space is formed integrally with one of the paper guides 12.

When the upper frame 1 is closed, the upper frame 1 is held in a closed state by projecting inward from an engagement lever 19 attached to the outside of the upper plate 7 of the upper frame and an inner plate of the lower frame. This is performed by engagement with the locking pin 42. The engagement lever 19 has a receiving portion 21 having a Y-shaped tip, and is pivotally supported by the upper plate 7 so that the receiving portion 21 can swing up and down. A tension spring 22 stretched between the engagement lever 19 and the upper plate 7 is connected to the base end of the engagement lever 19. Depending on the positional relationship between the biasing direction of the spring 22 and the swing center of the engagement lever 19, The swing of the engagement lever 19 is a flip-flop operation. When the upper frame 1 is closed, the upper frame 1
The upper lever 1 is held closed by the urging force of the tension spring 22.

The paper feed roller 35 is provided on the upper plate 3 of the lower frame.
6, the upper frame 36 of the lower frame is provided with an opening 43 through which the paper feed roller 35 protrudes. Both ends of the shaft 34 of the feed roller are supported by bearings 44 fitted in holes 33 formed in the inner plate 38 on the side wall of the lower frame.

The driven roller 5 of the first feed roller 5
b is supported by a U-shaped bracket 46 provided at the center of the upper plate of the upper frame. The driven roller 5b is urged toward the drive roller 5a by the bending elasticity of the upper surface plate 36 of the synthetic resin lower frame to pinch the sheet. The biasing force at this time can be adjusted by the thickness of the upper surface plate 36 of the lower frame, the shape of the reinforcing rib 41 provided on the back surface thereof, and the like.

The drive rollers 5a and 6a of the feed rollers mounted on the upper frame 1 are mounted by supporting both ends of the shafts 5c and 6c with bearings 23 fitted in holes 3 and 4 provided in the upper plate 7. Have been. At one end of the drive roller shafts 5c and 6c, a retaining ring 24 such as a C clip is provided, and a belt pulley 25 is fixed to the shaft end with a set screw 26. The bearing 23 on this side includes a retaining ring 24 and a belt pulley 2.
5 and the bearing 23 and the shafts 5c and 6c.
Is prevented from moving in the axial direction. On the other hand, the shaft 5c,
The other end of 6c is the bearing 2 fitted in the holes 3 and 4 of the upper plate 7.
3 is supported so that it can slightly move in the axial direction.
Due to this play, a difference in thermal expansion between the upper frame 1 made of synthetic resin and the roller shafts 5c and 6c made of metal is absorbed.

The pick roller shaft 34 shown in FIG. 2 has a similar structure and absorbs the difference in thermal expansion between the synthetic resin lower frame 31 and the metal pick roller shaft 34. That is, one end of the pick roller shaft 34 holds the bearing 44 in the axial direction between the pick roller driving gear 47 and the C-clip 48 at the shaft end, thereby forming a relative axial direction between the bearing 44 and the shaft 34. The movement is prevented, and the other end is configured to be supported by the bearing 44 so as to be slightly free to move in the axial direction.

Driving roller shafts 5c, 6 of the feed rollers
A timing belt 27 is wound around and driven by the belt pulley 25 fixed to the shaft end of c and the belt pulley 25a fixed to the output shaft of the feed roller drive motor 17 described above. The belt pulleys 25 and 25a and the timing belt 27 are located in a space between the upper plate 7 and the inner plate 38 of the lower frame with the upper frame 1 closed, and no mechanical part appears outside the device. In addition, when the upper frame 1 is opened, maintenance and inspection are easily performed. The timing belt 27 in the figure has a triangular shape because two feed rollers 5 and 6 are synchronously driven by one motor 17.

A space for accommodating the separation pad 28 is formed in the center of the top end of the upper frame 1 by partially cutting out the reinforcing rib 11. The separation pad 28 is mounted on a metal bracket 29 with its upper side fixed, and is urged toward the paper feed roller 35 by an urging spring (not shown). On both sides of the separation pad 28, a strip-shaped pressure spring 30 with a sheet made of a thin spring plate is disposed with the upper side fixed to the bracket 29. Pressure spring with paper 3
Numeral 0 indicates that the paper is pressed against the paper feed roller 35 so that a sufficient paper feeding force is applied to the paper. The separation pad 28 that prevents the passage of two or more papers and the paper one by one are surely provided. Has the effect of supplying.

[0039]

According to the present invention described above, it is possible to simplify the housing structure of the automatic sheet feeder provided in the image reading apparatus and the like, to reduce the number of parts thereof, and to greatly reduce the number of assembling steps. In addition, there is an effect that an image reading device or other information processing device having an automatic sheet feeding device can be provided at a lower cost.

In addition, by integrally forming the paper guide surface, which has a complicated structure and high accuracy, with the frame, a complicated paper guide formed by a metal plate in the related art becomes unnecessary, and the cost due to the reduction in the number of parts is reduced. In addition to the reduction, it is possible to stabilize the quality of the device, and furthermore, there is an effect that the appearance of the device is not deteriorated by simplifying the housing structure.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an embodiment seen from below an upper frame.

FIG. 2 is an exploded perspective view of the lower frame of the embodiment as viewed from above.

FIG. 3 is a perspective view showing the appearance of the apparatus of the embodiment.

FIG. 4 is a cross-sectional view of an image reading device with an automatic sheet feeding device.

[Explanation of symbols]

 Reference Signs List 1 upper frame 3 hole 4 hole 5 paper feed roller device 5a drive roller 5b driven roller 6 paper feed roller device 7 upper plate 8 fulcrum shaft 11 reinforcing rib 12 paper guide 23 bearing 31 lower frame 33 hole 35 paper feed roller device 36 upper plate 37 Side wall 38 Inner plate 39 Outer plate 41 Reinforcement rib 44 Bearing 51 Body C Paper passage

Claims (7)

(57) [Claims] A paper path (C) is formed to traverse the apparatus, and a fixed lower frame (31) and an upper frame (1) openable upward are provided with the paper path interposed therebetween. in the automatic sheet feeder of an information processing apparatus having a structure paper path (C) is opened when the opening frame (1), the upper and lower frame
(1,31) with paper guide surface (2,32)
The upper and lower frames (1, 31) are resin molded products.
It has side walls (7,37) on either side of the road,
The side wall (37) of the room (31) has an inner plate (38) and an outer plate (39).
It has a double structure, and the side wall (7) of the other frame (1) is
Located inside the side wall (37) of one frame,
Of the roller shaft of the roller device (5, 6, 35)
The roller shaft supported by (1) is suspended between the inner plates (38, 38).
The roller shaft supported by the other frame (1) is
Characterized in that it is suspended between the side walls (7, 7) of the frame.
That automatic sheet feeder. 2. The roller shaft of a paper feed roller device (5, 6, 35)
Fit into holes (3,4,33) provided in the side wall or its inner plate (7,38)
One end of the bearing (23,44) is immovable relative to the axial direction.
2. The automatic sheet feeding device according to claim 1, wherein the automatic sheet feeding device is inserted so as to be relatively movable in an axial direction and is mounted on a shaft . 3. A paper guide surface for guiding a lower surface of a sheet is provided.
Elasticity that connects the side walls (37) on both sides of the lower frame (31) together
It is formed of a flexible plate-like upper plate (36), and the upper plate
On the lower side, reinforcement of the paper feed direction perpendicular to the paper guide surface
The automatic sheet feeding device according to claim 1, wherein the rib (41) is provided in a comb shape . 4. An upper frame (1) having an elastically flexible plate-like shape.
An upper plate (10) is provided, and a paper guide is provided below the upper plate.
The reinforcing ribs (11) in the paper feed direction perpendicular to the
The reinforcing ribs are formed integrally, and the top edge of the reinforcing ribs
A paper guide surface for guiding
The automatic sheet feeding device according to claim 1, wherein 5. The upper frame (1) guides the upper surface of the paper.
Strip-shaped metal plate paper guide (1
2) is attached, this metal plate paper guide
Is fixed at one longitudinal end to one side wall (7) of the upper frame.
And the other end of the upper frame
To the other side wall (7) of the arm
Backed up at the tip of the
Motomeko 4 Symbol mounting automatic paper feeder of. 6. A paper feed roller device (5) sandwiching a paper path.
A driving roller (5a) and a driven roller (5b)
The driven roller (5b) is located at the center of the upper
Bullets that are pivotally supported and are caused by bending of the upper surface plate in the paper width direction.
It is pressed against the drive roller (5a) by the restoring force
The automatic sheet feeding device according to claim 3 or 4, wherein 7. The upper and lower frames (1, 31) serve as automatic paper feeders.
Same as the synthetic resin frame (51) of the information processing device to be mounted
Molded with synthetic resin having the same coefficient of thermal expansion,
Automatic paper feeder as claimed in any one of the Motomeko 1 to 6.