JP2008205971A - Image reader - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and surely perform an adjustment operation of an angle posture of a carriage while a support state with a guide axis and a connection state with a transfer means are established in an image reader having a single-holding support type carriage. <P>SOLUTION: The carriage 21 is constituted by dual partitioning structure of a bearing block 30 and a scanner block 31 and an angle adjustment mechanism S is provided between the bearing block 30 and the scanner block 31. Thus, the adjustment operation of the angle posture of the carriage 21 is easily and surely performed while the support state with the guide axis 22 and the connection state with an endless belt 28 are established and the angle posture of the carriage 21 is adjusted irrespective of work experience and a degree of proficiency. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention includes a carriage having a reading unit for reading a document, a guide shaft that guides and supports the carriage so as to be movable along the scanning direction, and a moving unit that moves the carriage along the guide shaft. The present invention relates to an image reading apparatus assembled in a frame constituting a mounting table. This image reading apparatus is applied to a scanner, a facsimile, a copying machine, and the like.

  In this type of image reading apparatus, in order to read a document accurately, it is necessary to match a skew which is an inclination of the read resist or scan line. Of these, the resist can be handled by software, but the skew cannot be handled by software, and an accurate original image cannot be obtained unless the sliding direction of the carriage and the reading line of the carriage are exactly perpendicular. Therefore, high accuracy is required for adjusting the inclination of the carriage with respect to the carriage scanning direction.

  For this reason, various types of carriage angle adjustment mechanisms have been proposed. For example, Patent Documents 1 and 2 disclose that the carriage inclination angle is changed by changing the mounting position of the carriage with respect to the wire constituting the moving means. An angle adjustment mechanism that can be finely adjusted has been proposed.

JP-A-6-62173 JP 2000-261622 A

  In the angle adjustment mechanisms of Patent Documents 1 and 2, the connection state with the wire constituting the moving means is released, the carriage is moved, the inclination angle is adjusted, and then the connection state with the wire is established again. For this reason, it takes time and effort to rewire the wire. In order to obtain a precise document image, it is necessary to perform adjustment work many times, but it is disadvantageous in that the work is complicated and the readjustment work takes time. If an operator who does not have specialized skills makes adjustments, the wire may be pulled carelessly, leading to poor carriage travel.

  In particular, as in the present invention, in the case of a cantilever support structure in which only one side end of the carriage is supported and connected to the guide shaft and the moving means, the carriage is opposite to the scanning direction due to rattling of the support portion. It tends to be inclined in a direction (see FIG. 4 of the present invention). In other words, in order to ensure a good sliding movement state, it is indispensable to secure a slight margin gap between the guide shaft and the guide hole that holds the guide shaft in an outer fitting shape. Due to the frictional force acting on the lower surface, it is inevitable that the free end portion moves with respect to the support / connecting portion and the carriage can be slightly swung in the direction opposite to the scanning direction. In addition, even when a slight gap occurs in the carrying portion due to design error between the guide shaft and the guide hole or wear due to sliding, the carriage is likely to swing.

  For this reason, in the cantilever type image reading apparatus, in consideration of the delay of the free end portion, the reading line becomes straight when moving in the scanning direction (the reading line is perpendicular to the scanning direction). Thus, it is necessary to adjust the angular posture of the carriage, and it has been desired to establish an angle adjustment mechanism that can easily and reliably perform the angle adjustment work.

  The object of the present invention is to enable easy and reliable adjustment of the angle and orientation of the carriage while the support state with the guide shaft and the connection state with the moving means are established. An object of the present invention is to provide an image reading apparatus provided with an angle adjustment mechanism that can easily adjust and absorb a deviation in posture as needed.

The present invention according to claim 1 is a carriage having a reading unit for reading a document, a guide shaft for guiding and supporting the carriage so as to be movable along the scanning direction, and a moving unit for moving the carriage along the guide shaft. And an image reading apparatus that is assembled in a casing constituting a document placing table. The carriage is configured to be movable along the guide shaft in a cantilevered state where only one side end is supported by the guide shaft and the moving means, and the carriage slides on the guide shaft. The bearing block is movably supported and connected to the moving means, and the scanner block includes the reading means.
An angle adjusting mechanism is provided between the bearing block and the scanner block to adjust the horizontal angle posture of the scanner block with respect to the bearing block.

  According to a second aspect of the present invention, the angle adjusting mechanism includes a vertical axis that pivotally supports the scanner block with respect to the bearing block, and an arbitrary angular attitude around the vertical axis. And a fastener for fastening and fixing the block. The fastener includes a screw hole formed in the bearing block and a screw body that is screwed into the screw hole through a screw through hole formed in the scanner block. The screw hole is formed in a long hole shape that avoids interference with the screw body.

  According to a third aspect of the present invention, it is preferable that the screw through hole is formed in a partial arc shape with the vertical axis as the center.

  According to a fourth aspect of the present invention, in the scanner block, a swing arm having the screw passage hole and a connecting arm having a shaft insertion hole for the longitudinal axis are integrally extended in the horizontal direction. Can be formed. And it is preferable to open in the said rocking | fluctuation arm the two partial arc-shaped screw through-holes which have a different diameter size centering on the said vertical axis | shaft.

  According to the first aspect of the present invention, the carriage is divided into a two-part configuration of a bearing block supported and connected to the guide shaft and the moving unit and a scanner block including the reading unit. In addition, an angle adjustment mechanism for adjusting the horizontal angle posture of the scanner block with respect to the bearing block is provided. Therefore, even if the deviation of the angular posture of the carriage occurs due to use or the like, the deviation can be absorbed by adjusting the angular posture of the scanner block, and the reading line by the reading unit is made to coincide with the reference line, The reading accuracy of the image reading apparatus can be improved.

  Above all, the carriage has a two-part structure consisting of a bearing block and a scanner block, so that the support state with the guide shaft and the connection state with the moving means remain established, making it easy and reliable to adjust the carriage's angular posture. It is excellent in that the angle and posture can be adjusted regardless of the work experience and the degree of skill. In addition, since the adjustment operation of the angular posture of the carriage can be performed while the support state with the guide shaft and the connection state with the moving means are established, the readjustment operation can be easily performed as necessary. The labor and time required for readjustment can be greatly reduced.

  According to the second aspect of the present invention, the screw hole for the screw body is formed in the bearing block and the long hole-like screw through hole is formed in the scanner block, so that the screw body is loosened and fastened to the screw hole. After releasing the state and placing the scanner block on the bearing block so that it can swing around the vertical axis, the posture of the scanner block is displaced, and then the screw body is fastened to the screw hole. Adjustments can be made. Therefore, the posture adjustment work can be performed easily and quickly.

  If the screw through hole is formed in a partial arc shape with the vertical axis as the center as in the present invention described in claim 3, the screw block is guided by the screw body, and the scanner block is arranged around the vertical axis. The posture can be displaced. Therefore, the angle adjustment can be performed reliably and simply, and the labor required for the angle adjustment can be reduced.

  According to a fourth aspect of the present invention, when the swing arm having the screw passage hole and the connecting arm having the shaft insertion hole for the longitudinal axis are integrally projected from the scanner block, The number of points and processing cost can be reduced, and an image reading apparatus having an angle adjustment mechanism as a whole can be provided at low cost. If two screw holes are formed at the concentric position of the swing arm, the posture of the scanner block can be displaced around the vertical axis while these two screw holes are guided by the corresponding screw bodies. The posture of the scanner block in the temporarily fixed state is stabilized. It is also excellent in that the scanner block is supported at three points by the vertical axis and two fasteners, so that the scanner block can be held in an adjusted angular posture in a stable state at all times.

(First embodiment)
1 to 6 show a first embodiment in which an image reading apparatus according to the present invention is applied to a multifunction machine having a copy function and a facsimile function. In FIG. 2, the multi function device 1 includes a paper feeding cassette 2, an image recording unit 3 that forms an image on a recording paper sent from the paper feeding cassette 2 through a paper feeding path, and the image recording unit. 3 and an image reading unit (image reading device) 4 disposed above 3. The image recording unit 3 is provided with a process unit 5 that is responsible for image formation on recording paper. The process unit 5 includes a photoconductor unit 6 and a toner cartridge 7 that supplies toner to the photoconductor unit 6. On the upper surface of the image reading unit 4, an operation panel 8 having various operation buttons and an automatic document feeder 9 (ADF) are provided.
In the present embodiment, for convenience of explanation, the extending direction of the operation panel 8 is defined as the left-right direction (see FIG. 2). Moreover, the direction orthogonal to the left-right direction and the horizontal direction is defined as the front-rear direction (see FIG. 3).

  As shown in FIG. 3, the image reading unit 4 includes a document placing table 11 on which a platen glass 10 on which a document to be read is placed is disposed, and a document presser that presses and fixes the document onto the platen glass 10. And a cover 12. The document presser cover 12 is configured to be swingable around a pair of left and right hinges 13 and 13, and an automatic document feeder 9 is disposed in the casing. As shown in FIG. 4, the casing 15 constituting the document table 11 includes a substantially square dish-shaped bottom frame 16 having an upper opening, a frame cover 17 that closes the upper opening of the bottom frame 16, and the like. . The frame cover 17 has a square frame shape having a central opening, and the platen glass 10 and the cover plate 18 (see FIG. 1) are assembled to the central opening.

  As shown in FIG. 1, the bottom frame 16 has a carriage 21 having a scanner unit 20 (reading means) for reading a document, and a guide shaft that guides and supports the carriage 21 so as to be movable along the left and right scanning directions. 22 and a belt driving mechanism 23 (moving means) for moving the carriage 21 along the guide shaft 22 are disposed. The scanner unit 20 includes a light source that irradiates scanner light toward an original on the platen glass 10, a CCD image sensor that reads an image by converting reflected light from the original into an electrical signal, and the like. As shown in FIGS. 1 and 3, the guide shaft 22 that runs in the left-right direction is disposed closer to the rear of the bottom frame 16. As shown in FIGS. 4 and 5, the belt driving mechanism 23 is disposed below the guide shaft 22.

  As shown in FIGS. 1, 3, and 5, the belt drive mechanism 23 includes a speed reduction mechanism 25 (see FIG. 1) including a motor assembled at the right back corner portion of the bottom frame 16, and a speed reduction shaft of the speed reduction mechanism 25. A driving pulley 26 fixed to the bottom frame 16, a driven pulley 27 disposed at the left back corner of the bottom frame 16, and an endless belt 28 wound between the pulleys 26 and 27. As shown in FIG. 5, a belt clamp 29 is provided on the rear end surface of the carriage 21 so as to sandwich and hold the endless belt 28. The carriage 21 is moved along the guide shaft 22 in the left and right directions as the endless belt 28 rotates. It can be moved in the scanning direction.

  The carriage 21 is supported by a guide shaft 22 so as to be slidable, and includes a bearing block 30 connected to an endless belt 28 via a belt clamp 29 and a scanner block 31 including a scanner unit 20. The both 30 and 31 are connected by a vertical axis 32, and the scanner block 31 is configured to be swingable in the horizontal direction around the vertical axis 32 with respect to the bearing block 30.

  Between the bearing block 30 and the scanner block 31, an angle adjusting mechanism S that adjusts the horizontal angle posture of the scanner block 31 with respect to the bearing block 30 is provided. The angle adjusting mechanism S includes the above-described vertical axis 32 and a fastener 33 that fastens and fixes the scanner block 31 at an arbitrary angle and orientation around the vertical axis 32. The fastener 33 is composed of a screw hole 35 to be described later and a screw (screw body) 36 that is screwed into the screw hole 35.

  As shown in FIG. 7, the bearing block 30 includes a left and right horizontally-long rectangular parallelepiped base block 38 having a shaft insertion hole 37 that allows the insertion of the vertical axis 32, and a pair of left and right holders protruding from the rear end of the base block. It is a resin molded product formed integrally with 39 and 39. A belt clamp 29 is attached to the left and right center of the lower surface of the base block. Guide holes 41 that allow the guide shaft 22 to be inserted are passed through the holder 39 in the horizontal direction on the left and right. The inner diameter dimension of the guide hole 41 is set slightly larger than the outer diameter dimension of the guide shaft 22, and the guide shaft 22 is supported by the guide holes 41 and 41 of the two holders 39 and 39 in FIG. The carriage 21 can be slid in the horizontal direction between the left end position indicated by the solid line and the right position indicated by the phantom line. Screw holes 35 and 35 opened at the upper surface of the block 38 are formed at two positions on the left and right sides of the base block 38.

  The scanner block 31 includes a base block 50 made of a resin having a substantially rectangular shape which is horizontally long in the front-rear direction. On the rear end surface of the base block 50, a single swing arm 51 and a pair of upper and lower connecting arms 52, 52 are formed integrally and projecting in the horizontal direction. The connecting arm 52 has a shaft insertion hole 53 for the vertical axis 32. 1, 4, and 6, reference numeral 45 indicates a rib that runs in the left-right direction in contact with the lower surface of the free end portion of the base block 50 of the scanner block 31. Is accepted. The rib 45 protrudes upward from the bottom surface of the bottom frame 16.

  As shown in FIG. 7, the vertical axis 32 pivotally supporting the scanner block 31 with respect to the bearing block 30 includes a shaft 46 and a retaining collar 47 provided on the upper portion of the shaft 46. In the vicinity of the lower end of the shaft 46, a groove 49 for the ring 48 is formed. The shaft 46 is inserted into the shaft insertion holes 53, 37, 53 of the upper connection arm 52, the base block 38 of the bearing block 30, and then the lower connection arm 52 from above, and the shaft insertion holes of the lower connection arm 52 are inserted. By attaching the ring 48 to the groove 49 at the lower end of the shaft 46 protruding from 53, the vertical axis 32 can be assembled in a vertical posture. At this time, the flange 47 is received by the opening edge of the shaft insertion hole 53 of the upper connecting arm 52, thereby preventing the vertical axis 32 from coming off downward.

  Corresponding to the previous screw hole 35, two partial arc-shaped screw through holes 54, 54 having different diametrical sizes with the longitudinal axis 32 as the center are opened at two positions on the left and right of the swing arm 51. Yes.

  With the angle adjustment mechanism S configured as described above, the angle adjustment work can be performed in the following procedure. First, the vertical axis 32 pivotally supports the scanner block 31 with respect to the bearing block 30 and then screws the screw 36 incompletely into the screw hole 35 through the screw through hole 54. As a result, the scanner block 31 can be brought into a temporarily fixed state capable of swinging with respect to the bearing block 30. Since the screw holes 54 and 54 are formed in a partial arc shape, the opening edges of the screw holes 54 and 54 of the swing arm 51 do not interfere with the screws 36 and 36. Accordingly, the scanner block 31 can be displaced in the horizontal direction around the vertical axis 32 in a state where the screw through holes 54 and 54 are guided by the corresponding screws 36 and 36.

  From this temporarily fixed state, the scanner block 31 is swung around the vertical axis 32 and the posture is displaced to an arbitrary angle. As shown in FIG. 8A, when the carriage 21 is moved in the scanning direction (rightward direction), the free end side (front end side) acts on the base end side due to the frictional force acting between the ribs 45. Easier to move after (rear end side). Therefore, as shown in FIG. 8B, the angular posture of the scanner block 31 with respect to the bearing block 30 is adjusted in advance so that the free end portion is inclined to the scanning direction side (right side). Thus, the reading line L of the scanner unit 20 at the time of scanning can be matched with the reference line E.

  When the angular posture of the scanner block 31 is determined, the two screws 36 and 36 are completely screwed into the corresponding screw holes 35 and 35, and the scanner block 31 is fastened and fixed to the bearing block 30. Thus, the scanner block 31 can be held in the adjusted angular posture. At this time, the scanner block 31 can be supported at three points by the vertical axis 32 and the two fasteners 33, so that the scanner block 31 can be stably held and fixed in the adjusted angular posture. After the angle adjustment, the manuscript is read and the degree of distortion of the manuscript image is confirmed. If necessary, the adjustment operation is performed again according to the previous procedure.

  As described above, in the present embodiment, the carriage 21 has a two-part configuration of the bearing block 30 supported and connected to the guide shaft 22 and the endless belt 28 and the scanner block 31 including the scanner unit 20. Between the block 30 and the scanner block 31, an angle adjustment mechanism S that adjusts the horizontal angle posture of the scanner block 31 with respect to the bearing block 30 is provided. Therefore, even if a deviation in the angular posture of the carriage 21 occurs due to use or the like, the deviation can be absorbed by adjusting the angular posture of the scanner block 31, and the reading line L by the scanner unit 20 is used as the reference line E. Thus, the reading accuracy of the image reading unit 4 can be improved.

  Since the carriage 21 has a two-part configuration of the bearing block 30 and the scanner block 31, it is easy to adjust the angular posture of the carriage 21 while the support state with the guide shaft 22 and the connection state with the endless belt 28 are established. In addition, the angle and orientation can be adjusted independently of the work experience and skill level. In addition, the adjustment operation of the angular posture of the carriage 21 can be performed while the support state with the guide shaft 22 and the connection state with the endless belt 28 are established, so that the readjustment operation can be easily performed as necessary. And the labor and time required for readjustment can be greatly reduced.

  Since the screw hole 35 for the screw 36 is formed in the bearing block 30 and the long hole-like screw through hole 54 is formed in the scanner block 31, the screw 36 is loosened by an operation tool such as a screwdriver and fixed to the screw hole 35. The state is released, and the scanner block 31 is temporarily fixed to the bearing block 30 so as to be swingable around the longitudinal axis 32, the posture of the scanner block 31 is displaced, and then the screw 36 is fastened to the screw hole 35. It is possible to adjust the posture simply by making it. Therefore, the posture adjustment work can be performed easily and quickly.

  When the screw hole 54 is formed in a partial arc shape with the vertical axis 32 as the center, the scanner block 31 can be displaced around the vertical axis 32 while the screw hole 54 is guided by the screw 36. . Therefore, the angle adjustment can be performed reliably and simply, and the labor required for the angle adjustment can be reduced.

  Further, a swing arm 51 having a screw passage hole 54 and a pair of upper and lower connecting arms 52 and 52 having a shaft insertion hole 53 for the longitudinal axis 32 are integrally extended from the base block 50 of the scanner block 31. As a result, the number of components and the processing cost can be reduced, and the multifunction device 1 including the angle adjustment mechanism S as a whole can be provided at low cost. If two screw holes 54 are formed at the concentric position of the swing arm 51, the scanner block 31 is positioned around the vertical axis 32 while these two screw holes 54 are guided by corresponding screws 36. The position of the scanner block 51 in the temporarily fixed state can be stabilized. It is also excellent in that the scanner block 31 is supported at three points by the vertical axis 32 and the two fasteners 33, and the scanner block 31 can be held in an adjusted angular posture in a stable state at all times.

In the above embodiment, the belt driving mechanism 23 including the endless belt 28 is employed as the moving means, but the present invention is not limited to this.
The swing arm 51 is not limited to the form disposed on the upper surface of the bearing block 30 and may be disposed on the lower surface. Further, a notch groove may be formed in the upper and lower central portions of the bearing block 30 and the swing arm 51 may be disposed in the groove.

1 is an internal plan view of an image reading apparatus according to a first embodiment of the present invention. 1 is a front view of a multifunction machine to which an image reading apparatus is applied. FIG. 2 is a plan view of the image reading apparatus, showing a state where a document pressing cover is pushed up. FIG. 3 is an internal plan view of a main part of the image reading apparatus. It is the sectional view on the AA line of FIG. It is a side view of the principal part which shows an angle adjustment mechanism. It is a disassembled perspective view of the principal part which shows an angle adjustment mechanism. (A) * (b) is a figure which shows the relationship between the reading line L and the reference line E. FIG.

Explanation of symbols

4 Image reading device (image reading unit)
11 Document Placement Table 15 Case 20 Reading Means (Scanner Unit)
21 Carriage 22 Guide shaft 23 Moving means (belt drive mechanism)
30 Bearing block 31 Scanner block 32 Vertical axis 33 Fastener 35 Screw hole 36 Screw body (screw)
37 Shaft insertion hole 39 Holder 41 Guide hole 50 Base block 51 Oscillating arm 52 Connecting arm 53 Shaft insertion hole 54 Screw through hole S Angle adjustment mechanism

Claims (4)

A carriage having a reading unit for reading a document; a guide shaft that guides and supports the carriage so as to be movable in the scanning direction; and a moving unit that moves the carriage along the guide shaft. An image reading apparatus assembled in a housing constituting
The carriage is configured to be movable along the guide shaft in a cantilevered state in which only one side end is supported by the guide shaft and the moving means,
The carriage is slidably supported on the guide shaft, and includes a bearing block coupled to the moving unit, and a scanner block including the reading unit.
An image reading apparatus, wherein an angle adjustment mechanism is provided between the bearing block and the scanner block to adjust a horizontal angle posture of the scanner block with respect to the bearing block. The angle adjustment mechanism includes a vertical axis that pivotally supports the scanner block with respect to the bearing block, and a fastener that fastens and fixes the scanner block at an arbitrary angle around the vertical axis.
The fastener includes a screw hole formed in the bearing block and a screw body that is screwed into the screw hole through a screw through hole formed in the scanner block.
The image reading apparatus according to claim 1, wherein the screw through hole is formed in a long hole shape that avoids interference with the screw body.   The image reading apparatus according to claim 2, wherein the screw hole is formed in a partial arc shape with the vertical axis as a center. In the scanner block, a swing arm having the screw passage hole and a connecting arm having a shaft insertion hole for the longitudinal axis are integrally formed so as to protrude horizontally.
The image reading apparatus according to claim 3, wherein the swing arm is provided with two partial arc-shaped screw through holes having different diameters with the longitudinal axis as a center.

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