JP3564443B2 - Scanner unit - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a structure of a scanner unit for reading a document image of an image reading device.
[0002]
[Prior art]
For example, a scanner unit for reading a document image of a copying machine or a facsimile machine is a traveling frame equipped with a scanner frame and an optical system having a light source for irradiating the document and a mirror for guiding the reflected light to a photosensitive drum or the like. And a rail member for guiding the traveling operation of the traveling frame.
[0003]
[Problems to be solved by the invention]
By the way, the above-mentioned scanner frame may be formed by welding a plurality of frame bodies in order to improve frame rigidity. In this case, a welding jig for positioning the frame body is used, and a positioning hole is formed in the scanner frame to be fitted to a positioning pin formed on the welding jig, and the scanner frame is positioned on the welding jig. Welding is performed in the state of being performed.
[0004]
On the other hand, mirrors and the like provided in the scanner frame are easily affected by foreign substances such as dust, so that it is required to prevent foreign substances from entering the scanner frame.
[0005]
However, in the conventional scanner frame, no measures have been taken against foreign matter intrusion from the above-described positioning holes, so that foreign matter may enter the scanner frame from the positioning holes. It is conceivable to close the above-mentioned positioning holes by taping or the like, but the number of steps and the number of parts increase accordingly.
[0006]
The present invention has been made in view of the above, and an object of the present invention is to prevent foreign substances from entering from the positioning holes in a scanner frame constituting a scanner unit of an image reading device without increasing man-hours or the number of parts. I do.
[0007]
[Means for Solving the Problems]
The invention according to claim 1 has a scanner frame formed by welding and joining a plurality of frame bodies, and a traveling surface for guiding a traveling operation of a traveling frame on which an optical system is mounted, and is orthogonal to the traveling surface. A rail member having a mounting surface closely attached to an inner surface of the scanner frame; and a predetermined welding jig for supporting the plurality of frame bodies when the plurality of frame bodies are welded and connected to the scanner frame. A positioning hole for positioning with respect to a tool is formed in a region where the mounting surface of the rail member is in close contact with the rail member, and is closed by the mounting surface when the rail member is mounted. .
[0008]
According to this invention, when welding the plurality of frame members, the positioning hole for performing positioning with respect to the predetermined welding jig supporting the plurality of frame members is formed in the area where the mounting surface of the rail member is in close contact. Since the positioning hole is formed in the scanner frame and the positioning hole is closed by the mounting surface when the rail member is mounted, intrusion of foreign matter from the positioning hole into the scanner frame is prevented. Further, since the rail member for guiding the traveling operation of the traveling frame also has the function of closing the positioning hole, an increase in the number of steps and the number of parts due to realizing prevention of intrusion of foreign matter is avoided.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment in which an image reading apparatus provided with a scanner unit according to the present invention is applied to a copying machine will be described, and then the features of the present invention will be described after describing the overall configuration thereof.
[0010]
FIG. 1 is a perspective view showing an external configuration of the copying machine 1, and FIG. 2 is a schematic diagram showing a schematic configuration of the copying machine 1. In the following description, the near side (when viewed from the direction of arrow A in FIG. 1) is referred to as the front of the copying machine when viewed from the normal operation position of the copying machine 1.
[0011]
As shown in FIG. 1, the copying machine 1 has an apparatus main body 2 and a document holder 3 mounted on the upper part of the apparatus main body 2 so as to be openable and closable. The apparatus main body 2 is divided by a main body housing 4 and an upper housing 5 placed on the upper part thereof. In an intermediate portion between the main body housing 4 and the upper housing 5, paper P from the main body housing 4 is supplied from the left side to the right side. A paper discharge unit 6 that is discharged toward is formed.
[0012]
As shown in FIG. 2, the upper housing 5 has a built-in image reading section 7 for reading an image by exposing and scanning an original at an image reading position. The image reading unit 7 includes first and second traveling frames 12 and 13 in which an optical system including an exposure lamp 9 and mirrors 10 and 11 is mounted in a substantially rectangular scanner frame 8 (see FIG. 3). 14, a CCD line sensor 15, a rail member 16 having a U-shaped cross section for guiding the traveling operation of the first and second traveling frames 12, 13, and the like.
[0013]
The first traveling frame 12 has an exposure lamp 9 for irradiating the original with light, and a mirror 10 for reflecting light reflected from the original to the second traveling frame 13. The mirror 11 reflects the light reflected from the traveling frame 12 toward the CCD line sensor 15.
[0014]
The original placed on the contact glass 18 is irradiated with light by the exposure lamp 9 while the first and second traveling frames 12 and 13 are reciprocated in the left-right direction of FIG. Then, the reflected light is guided to the CCD line sensor 15 via the lens 14 to read image information of the entire surface of the document.
[0015]
As shown in FIGS. 1 and 2, the main body housing 4 includes a paper supply unit 19 provided at a lower portion, a first paper transport unit 20 provided above the paper supply unit 19, and a first paper A lower housing 23 containing an image forming unit 21 disposed above the conveying unit 20 and a fixing unit 22 disposed downstream of the image forming unit 21 in the sheet conveying direction, It is partitioned by a connection housing 25 containing a second paper transport unit 24 for transporting and discharging the paper to the paper discharge unit 6.
[0016]
The paper supply unit 19 sends out the paper P stacked and placed on the paper supply cassette 26 to the outlet side (the left side in FIG. 1) of the paper supply cassette 26 by the rotation operation of the paper supply roller 27, and the width of the paper supply cassette 26. The sheet P at the uppermost position is fed one by one to the sheet transporting unit 20 by separating the sheet P by a separating claw (not shown) provided at the upper portion of both ends in the direction.
[0017]
The first paper transport unit 20 transports the paper fed from the paper feed unit 19 toward the image forming unit 21 by the transport roller pair 28, the registration roller pair 29, and the pre-transfer guide 30.
[0018]
The image forming section 21 includes a photoconductive drum 31 rotatably supported on a photoconductive drum, a charger 32 and a laser scanning unit (LSU) 33 around the photoconductive drum 31 along the rotation direction thereof. , A developing unit 34, a transfer unit 35, a cleaning unit 36, and a discharge lamp 37, and forms a predetermined toner image on the photosensitive drum 31 by an electrophotographic process, and transfers the toner image to a sheet.
[0019]
The charger 32 charges the photosensitive drum 31 to a fixed polarity (positive in this embodiment).
[0020]
The laser scanning unit (LSU) 33 outputs a laser beam, which is intensified according to the image data of the document read by the image reading unit 7, from the laser emitter 38, and outputs the laser beam via the polygon mirror 39 and the reflecting mirror 40. Irradiates the exposed area of the photosensitive drum 31 charged to the positive polarity. The irradiated laser light reduces the surface potential of the photosensitive drum 31 in accordance with the image, and forms an electrostatic latent image on the surface of the photosensitive drum 31 in accordance with the document image data. This light irradiation is repeatedly scanned in the width direction of the rotating photosensitive drum 31 to the exposure area between the charger 32 and the developing unit 34 by the rotation of the polygon mirror 39.
[0021]
The developing unit 34 attaches the same polarity, that is, positively charged toner in the developing area to the portion of the electrostatic latent image on the photosensitive drum 31 where the positive charge is reduced (the potential is reduced) on the photosensitive drum 31 by the laser beam. . As a result, the electrostatic latent image formed on the photosensitive drum 31 is developed with the toner, and a toner image is formed on the surface of the photosensitive drum 31 as a visible image.
[0022]
The transfer device 35 performs a negative corona discharge from the back surface of the sheet by a transfer roller 41 disposed in a transfer area of the photosensitive drum 31 to electrostatically transfer the toner image formed on the photosensitive drum 31. It is to be transferred onto paper.
[0023]
The cleaning unit 36 urges the tip of the cleaning blade (not shown) to the surface of the photoconductor drum 31 by the urging force of the urging means (not shown), and the residual portion adhered to the surface of the photoconductor drum 31 after the transfer. This is to scrape off the toner.
[0024]
Although not shown in detail, the static elimination lamp 37 includes a plurality of LED lamps arranged in a row or a plurality of rows in an array over the entire width of the photosensitive drum 31, and is configured to receive LED lamp light. Irradiation is performed on the surface of the body drum 31 to remove residual charges on the photosensitive drum 31.
[0025]
The fixing unit 22 is disposed downstream of the image forming unit 21 in the sheet conveying direction, and presses the sheet on which the toner image has been transferred in the image forming unit 21 with a heating roller 42 having a heater therein and the heating roller 42. The toner image is heated and pressurized by being sandwiched between the pressure rollers 43 to be fused and fixed on the paper.
[0026]
The second sheet transport unit 24 discharges the sheet P on which an image has been formed by the image forming unit 21 from the fixing unit 22 to the sheet discharge unit 6 via the discharge roller pair 44.
[0027]
Next, a portion according to the present invention will be described.
[0028]
FIG. 3 is an overall perspective view of the scanner frame 8 provided in the image reading unit 7.
[0029]
As shown in FIG. 3, a rail member 16 having a U-shaped cross section is attached to the inner surfaces of the front and rear side plates 81 and 82 of the scanner frame 8. Of the three surfaces of the rail member 16, two parallel surfaces 16a and 16b (see FIG. 4) are traveling surfaces (hereinafter, traveling surfaces 16a and 16b) for reciprocating the first and second traveling frames 12 and 13. ), And the remaining surface 16c (see FIG. 4) is a mounting surface (hereinafter, referred to as a mounting surface 16c) that is in close contact with the inner surfaces of the front and rear side plates 81 and 82 of the scanner frame 8, and the rail member 16 is connected to the scanner frame. 8 are attached to the front and rear side plates 81 and 82 by screws 17 substantially horizontally. The holes 81a and 82a shown in FIG. 3 are screw holes into which the screws 17 are screwed, and are formed on the left and right sides of the front and rear side plates 81 and 82.
[0030]
FIG. 4 is a sectional view of the scanner frame 8 and the rail member 16.
[0031]
As shown in FIG. 4, in order to position the rail member 16 with respect to the front and rear side plates 81 and 82 when attaching the rail member 16 to the scanner frame 8, a column is provided at an appropriate position on the inner surface of the front and rear side plates 81 and 82 of the scanner frame 8. A boss portion 8c having a protruding portion is formed, and a circular hole portion 16d having substantially the same diameter as the cylindrical portion of the boss portion 8c is formed on the rail member 16, and the boss portion 8c and the circular hole are formed. The rail member 16 is positioned with respect to the front and rear side plates 81 and 82 by fitting with the portion 16d.
[0032]
As shown in FIG. 5, the scanner frame 8 is created by welding the frame body while being fixed to the welding jig 45. Note that, for convenience of explanation, the frame body is given the same number “8” as the scanner frame.
[0033]
As shown in FIG. 5, the welding jig 45 includes a cylinder 452 mounted and fixed on a base 451, and a positioning unit 454 having a rectangular workpiece 453 mounted on the tip of a rod 452a of the cylinder 452. The positioning block 453a and the positioning pin 453b for positioning the frame body 8 are attached to the surface of the work 453 facing the frame body 8 so as to correspond to the front and rear side plates 81 and 82. ing. On the other hand, as shown in FIGS. 3 and 5, positioning holes 81 b and 82 b corresponding to the positioning pins 453 b of the welding jig 45 are formed in the front and rear side plates 81 and 82 of the frame body 8.
[0034]
When the welding of the frame body 8 is performed, the frame body 8 is placed on the base 451 of the welding jig 45, the rod 452a of the cylinder 452 projects, and the positioning pin 453b of the welding jig 45 is moved. The positioning block 453a is pressed against the front and rear side plates 81, 82 of the frame body 8 while being fitted into the positioning holes 81b, 82b of the frame body 8, respectively. Thereby, the frame body 8 is positioned on the welding jig 45.
[0035]
As described above, in the scanner frame 8 in which the positioning holes 81b and 82b are formed in the front and rear side plates 81 and 82, there is a possibility that foreign matter such as dust may enter through the positioning holes 81b and 82b.
[0036]
Therefore, as described above, since the rail member 16 having a U-shaped cross section is attached to the front and rear side plates 81 and 82 in close contact with each other, the screw holes 81a and 82a and the bosses are formed in this embodiment as shown in FIG. The portion 8c and the positioning holes 81b and 82b are arranged in a straight line, and the positioning holes 81b and 82b are formed in the portion of the front and rear side plates 81 and 82 of the scanner frame 8 where the rail member 16 is in close contact, as shown in FIG. When the rail member 16 is attached to the front and rear side plates 81 and 82 of the scanner frame 8, the positioning holes 81 b and 82 b are closed by the attachment surface 16 c of the rail member 16.
[0037]
In this manner, the positioning holes 81b and 82b are not configured to prevent foreign matter from entering by using a new member such as taping, but are positioned on the rail member 16 for running the first and second running frames 12 and 13. By adopting a configuration that also serves to close the holes 81b and 82b, it is possible to prevent foreign substances such as dust from entering the scanner frame 8 from the positioning holes 81b and 82b while avoiding an increase in man-hours and the number of parts. be able to.
[0038]
In the above embodiment, the positioning holes 81b and 82b are closed by the mounting surface 16c of the rail member 16. However, as shown in FIG. 7, the positioning holes 81b and 82b are closed with the opening side facing downward. It may be. Further, as the rail member for guiding the traveling operation of the traveling frame, a rail member formed in a U-shaped cross section is used in the above embodiment, but a rail member formed in an L-shaped cross section as shown in FIG. 8 may be used.
[0039]
Further, in the above embodiment, the present invention is applied to the scanner unit of the copying machine. However, the present invention is not limited to this, and can be applied to a scanner unit provided in an image reading apparatus such as a facsimile apparatus and a scanner apparatus.
[0040]
【The invention's effect】
According to the present invention, a positioning hole for performing positioning with respect to a predetermined welding jig that supports the plurality of frame bodies when the plurality of frame bodies are welded to each other is formed in an area where the mounting surface of the rail member is in close contact. And the positioning hole is closed by the mounting surface when the rail member is mounted, so that foreign matter can enter the scanner frame from the positioning hole while avoiding an increase in man-hours and the number of parts. Can be prevented.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an external configuration of a copying machine.
FIG. 2 is a schematic diagram showing a schematic configuration of a copying machine.
FIG. 3 is an overall perspective view of a scanner frame provided in the image reading unit.
FIG. 4 is a sectional view of a scanner frame and a rail member.
FIG. 5 is a schematic plan view of a welding jig.
FIG. 6 is an explanatory diagram showing a characteristic portion of the present invention.
FIG. 7 is a cross-sectional view showing another embodiment for mounting a rail member.
FIG. 8 is a sectional view showing another embodiment of the shape of the rail member.
[Explanation of symbols]
7 Image reading section 8 Scanner frames 81b, 82b Positioning holes 45 Welding jigs 453b Positioning pins 12, 13 First and second traveling frames 16 Rail members

Claims (1)

A scanner frame configured by welding and joining a plurality of frame bodies,
It has a traveling surface for guiding the traveling operation of the traveling frame on which the optical system is mounted, and a rail member having a mounting surface orthogonal to the traveling surface attached to the inner surface of the scanner frame in close contact with the traveling surface,
The scanner frame has a positioning hole for positioning with respect to a predetermined welding jig supporting the plurality of frame bodies when the plurality of frame bodies are welded and joined, and the mounting surface of the rail member is in close contact therewith. A scanner unit formed in an area and closed by the mounting surface when the rail member is mounted.

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