JP2003075935A - Scanner unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent foreign matter from entering from a positioning hole with which positioning at a welding fixture is performed without increasing man-hour and the number of parts in the scanner unit of an image reader. SOLUTION: The positioning holes 81b and 82b are formed at parts with which a rail member 16 comes into close contact on the front and back side plates 81 and 82 of a scanner frame 8, and when the rail member 16 is attached to the front and back side plates 81 and 82 of the scanner frame 8, the positioning holes 81b and 82b are covered with the attaching surface 16c of the rail member 16.

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a structure of a scanner unit for reading a document image of an image reading apparatus. 2. Description of the Related Art For example, a scanner unit for reading a document image of a copying machine or a facsimile machine has a scanner frame, 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 that guides the traveling operation of the traveling frame. [0003] Incidentally, the above-mentioned scanner frame is sometimes made by welding a plurality of frame members in order to improve the rigidity of the frame. 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. Therefore, it is required to prevent foreign substances from entering the scanner frame. However, in the conventional scanner frame, no measures have been taken against foreign matter intrusion from the above-described positioning holes. Therefore, there is a possibility 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,
It is an object of the present invention to prevent foreign substances from entering through the positioning holes without increasing the number of steps and the number of parts in a scanner frame constituting a scanner unit of an image reading apparatus. According to a first aspect of the present invention, a scanner frame formed by welding and joining a plurality of frame bodies and a traveling operation of a traveling frame on which an optical system is mounted are guided. It has a running surface, and a mounting surface orthogonal to the running surface includes a rail member that is attached to the inner surface of the scanner frame in close contact with the scanner frame. A positioning hole for performing positioning with respect to a predetermined welding jig supporting the plurality of frame bodies is formed in a region where the mounting surface of the rail member is in close contact with the rail member, and the mounting surface is formed by mounting the rail member. It is characterized in that it is closed by. According to the present invention, when the plurality of frame members are welded to each other, a positioning hole for performing positioning with respect to a predetermined welding jig supporting the plurality of frame members is formed by the mounting surface of the rail member. Since the positioning hole is formed in the area where the rail member is attached and the positioning hole is closed by the mounting surface when the rail member is mounted, foreign matter can be prevented from entering the scanner frame from the positioning hole.
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. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 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 the overall configuration thereof will be described. explain. 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. 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. As shown in FIG. 2, the upper housing 5 includes
An image reading section 7 for reading an image by exposing and scanning a document at an image reading position is built in. Image reading unit 7
Are first and second traveling frames 12 and 13 and a lens 1 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).
4, CCD line sensor 15, first and second traveling frames 12,
13 is a U-shaped rail member 16 for inducing the running operation of
And so on. The first traveling frame 12 has an exposure lamp 9 for irradiating the original with light, and a mirror 10 for reflecting the reflected light from the original to the second traveling frame 13. ,
The reflected light from the first traveling frame 12 is transmitted to the CCD line sensor 15.
And a mirror 11 that reflects light toward the mirror. The first and second traveling frames 1 are driven by a drive unit (not shown).
2 is reciprocated at a predetermined speed in the left-right direction in FIG. 2 while irradiating a document placed on a contact glass 18 with light from an exposure lamp 9 and reflecting the reflected light through a lens 14 through a CCD line. By guiding to the sensor 15, the image information of the entire surface of the document is read. As shown in FIGS. 1 and 2, the main body housing 4 includes a sheet feeding portion 19 provided at a lower portion, and the sheet feeding portion 19.
, A first sheet transport section 20 disposed above the first sheet transport section 20, an image forming section 21 disposed above the first sheet transport section 20, and a downstream side in the sheet transport direction relative to the image forming section 21. A lower housing 23 containing the fixing unit 22 and a connecting housing 25 containing a second sheet conveying unit 24 for conveying the sheet after fixing and discharging the sheet to the sheet discharging unit 6. The paper supply unit 19 sends out the paper P stacked and mounted on the paper supply cassette 26 to the outlet side (the left side in FIG. 1) of the paper supply cassette 26 by rotating the paper supply roller 27. The sheet P at the uppermost position is fed one by one to the sheet transporting unit 20 by separating the sheet P by an unillustrated separating claw provided at an upper portion of both ends in the width direction of the sheet 26. The first paper transport section 20 transports the paper fed from the paper feed section 19 to a transport roller pair 28 and a registration roller pair 2.
9. Conveyance is performed by the pre-transfer guide 30 toward the image forming section 21. The image forming section 21 includes a photoconductive drum 31 rotatably supported on a photoconductive drum, and a charger 32 and a laser scanning unit (around the circumference of the photoconductive drum 31 along the rotation direction). An LSU) 33, a developing unit 34, a transfer unit 35, a cleaning unit 36, and a charge removing lamp 37, which form a predetermined toner image on the photosensitive drum 31 by an electrophotographic process, and transfer the toner image to paper. It is. The charger 32 charges the photosensitive drum 31 to a fixed polarity (positive in this embodiment). A laser scanning unit (LSU) 33 outputs from a laser light emitter 38 a laser beam that has been increased or decreased in accordance with image data of a document read by the image reading section 7, and outputs a polygon mirror 39 and a reflecting mirror 40. Through
This is for irradiating 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 according to an image,
An electrostatic latent image corresponding to the document image data is formed on the surface of the photosensitive drum 31. 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. The developing section 34 causes the same polarity, that is, positively charged toner to adhere to the portion of the electrostatic latent image on the photosensitive drum 31 where the positive charge has been reduced (the potential has been reduced) by the laser beam in the developing area. Things. 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. The transfer unit 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 transfer the toner image formed on the photosensitive drum 31 to a static state. It is to be electrically transferred onto paper. The cleaning unit 36 urges the tip of the cleaning blade (not shown) to the surface of the photosensitive drum 31 by the urging force of the urging means (not shown), and adheres to the surface of the photosensitive drum 31 after the transfer. The remaining toner is scraped off. Although not shown in detail, the discharge lamp 37 includes a plurality of L lamps over the entire width of the photosensitive drum 31 in the width direction.
The ED lamps are arranged in one or more rows and arranged in an array, and irradiate the surface of the photosensitive drum 31 with LED lamp light to remove residual charges on the photosensitive drum 31. The fixing section 22 is disposed downstream of the image forming section 21 in the sheet conveying direction, and heats the sheet on which the toner image has been transferred in the image forming section 21 with a heating roller 42 having a heater therein, The toner image is heated and pressed by being sandwiched by a pressure roller 43 pressed against the toner image 42 to fuse and fix the toner image on the paper. The second sheet transport section 24 discharges the sheet P on which an image has been formed by the image forming section 21 from the fixing section 22 to the sheet discharge section 6 via a discharge roller pair 44. Next, a portion according to the present invention will be described. FIG. 3 is an overall perspective view of the scanner frame 8 provided in the image reading section 7. 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 (FIG. 4)
) Is a running surface (hereinafter referred to as running surfaces 16a and 16b) for reciprocating the first and second running frames 12 and 13, and the remaining surface 16c (see FIG. 4) is in front of and behind the scanner frame 8. A mounting surface (hereinafter, referred to as a mounting surface 16c) that is in close contact with the inner surfaces of the side plates 81 and 82 is provided.
6 are screws 1 on front and rear side plates 81 and 82 of the scanner frame 8.
7 so as to be mounted substantially horizontally. Hole 8 shown in FIG.
1a and 82a 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, respectively. FIG. 4 is a sectional view of the scanner frame 8 and the rail member 16. As shown in FIG. 4, when the rail member 16 is mounted on the scanner frame 8, the front and rear side plates 81 and 82 are provided at appropriate positions on the inner surfaces of the front and rear side plates 81 and 82 of the scanner frame 8.
In order to position the rail member 16 with respect to 82, a projecting boss 8c having a cylindrical portion is formed, while the rail member 16 has a circular hole portion 16d having substantially the same diameter as the cylindrical portion of the boss portion 8c. The positioning of the rail member 16 with respect to the front and rear side plates 81 and 82 is performed by fitting the boss portion 8c and the circular hole portion 16d. As shown in FIG. 5, the scanner frame 8 is formed by welding a frame body in a state fixed to a welding jig 45. Note that, for convenience of explanation, the frame body is given the same number “8” as the scanner frame. 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 work 453 mounted on the tip of a rod 452a of the cylinder 452. Are provided corresponding to the front and rear side plates 81 and 82 of the frame body 8, and the surface of the work 453 facing the frame body 8 is provided with:
A positioning block 453a for positioning the frame body 8 and a positioning pin 453b are attached. 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. 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, and the rod 452a of the cylinder 452 projects.
The positioning pins 453b of the welding jig 45 are fitted into the positioning holes 81b and 82b of the frame body 8, respectively, and the positioning block 453a is pressed against the front and rear side plates 81 and 82 of the frame body 8. Thereby, the frame body 8 is positioned on the welding jig 45. 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. Therefore, as described above, the front and rear side plates 81,
Since the rail member 16 having a U-shaped cross section is closely attached to 82, in this embodiment, the screw holes 81a and 82a, the boss 8c, and the positioning holes 81b and 82b are aligned in a straight line as shown in FIG. The positioning holes 81b and 82b are provided in the front and rear side plates 81 and 82 of the scanner frame 8 at positions where the rail members 16 are in close contact with each other.
When the rail member 16 is attached to the front and rear side plates 81 and 82 of the scanner frame 8 as shown in FIG.
Positioning holes 81b, 8 are provided on mounting surface 16c of rail member 16.
2b is closed. As described above, instead of using a new member such as taping in the positioning holes 81b and 82b to prevent foreign matter from entering, the rail member 16 for running the first and second running frames 12 and 13 is used. And positioning holes 81b and 82
With the configuration that also serves as a function of closing the b, the increase in the number of man-hours and the number of parts can be avoided, and the positioning holes 81b, 8 can be prevented.
Foreign matter such as dust can be prevented from entering the scanner frame 8 from the second frame 2b. In the above embodiment, the rail member 16
Although the positioning holes 81b and 82b are closed by the mounting surface 16c, as shown in FIG. 7, the positioning holes 81b and 82b may be closed with the opening side facing downward. 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. In the above embodiment, the present invention is applied to a scanner unit of a 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. According to the present invention, when a plurality of frame members are welded to each other, a positioning hole for performing positioning with respect to a predetermined welding jig supporting the plurality of frame members is provided on the rail member. The mounting surface is formed in an area where the mounting surface is in close contact, and the positioning hole is closed by the mounting surface when the rail member is mounted. Therefore, the positioning hole is prevented while increasing the number of steps and the number of parts. Foreign matter can be prevented from entering the scanner frame from the scanner.

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. [Description of Signs] 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

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Masatoshi Uehara             Kyocera 1-2-2, Tamazo, Chuo-ku, Osaka-shi             Mita Corporation (72) Inventor Masayuki Nishi             Kyocera 1-2-2, Tamazo, Chuo-ku, Osaka-shi             Mita Corporation F-term (reference) 2H108 AA01 CB01 FB92 HA07                 5C072 AA01 EA05 LA20 XA01

Claims (1)

Claims: 1. A scanner frame comprising a plurality of frames joined by welding, and a traveling surface for guiding a traveling operation of a traveling frame on which an optical system is mounted. A rail member having a mounting surface orthogonal to the inner surface of the scanner frame in close contact with the scanner frame, wherein the scanner frame supports the plurality of frame members when the plurality of frame members are welded to each other. A scanner, wherein a positioning hole for performing positioning with respect to a welding jig 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. unit.