JP6481503B2 - Image reading apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to an image reading apparatus used for a printer or the like and an image forming apparatus equipped with the image reading apparatus.

  In the image reading apparatus, a flexible flat cable (hereinafter also referred to as FFC) is used as a wiring means to an illumination device installed on a traveling body. In addition, it is necessary to secure a high illuminance in the image reading apparatus with high productivity and a large number of copies, and a configuration in which a plurality of illumination devices are arranged is already known.

  As an example of such a configuration, for example, two illumination devices having an LED substrate having a connector at one end in the main scanning direction shown in FIG. 8 are opposed to each other in the sub-scanning direction with the reading optical axis as shown in FIG. There are two-lamp lighting configurations to be arranged. In this configuration, as shown in FIG. 10, the positions of the connectors on each LED board are laid out at two locations on the near side and the far side in the main scanning direction.

  A flexible flat cable is used as a power supply means to these lighting devices. It is composed of one FFC without branching from the power supply board to the center of the scanner frame, via the second mirror unit, and to the first mirror unit, and branches into two branches at the cable branch on the first mirror unit. It is set as a turning structure connected to the lighting device.

  At this time, as shown in FIG. 10, the cable path from the cable branch portion to the illumination device on the opposite side of the reading optical axis in the sub-scanning direction wraps around the side surface of the first mirror unit from the cable branch portion to the connector. In addition, there is a problem that the machine size is increased in order to secure a space for turning the FFC.

  For example, Patent Literature 1 and Patent Literature 2 describe a configuration of a cable around an illumination device in an image reading device.

  Patent Document 1 discloses a configuration in which a flexible flat cable is used in a harness path from a power supply source substrate to a first mirror unit in a differential mirror type scanner, and turning is performed. However, the illuminating device described in Patent Document 1 is not a two-lamp illumination configuration in which the reading optical axis is sandwiched and arranged facing each other in the sub-scanning direction, and there is no description about the winding of the cable in the two-lamp illumination configuration.

  Further, Patent Document 2 discloses a vertical in which two cores are vertically positioned from the lighting device on the optical scanning unit for the purpose of preventing a breakage of a cable due to leakage current or friction caused by contact with other components near the connector of the lighting device. A cable support configuration is disclosed in which a distribution cable led in a state is twisted so as to rotate 90 degrees by a regulation guide and led out in a horizontal state in which two cores are positioned on the left and right.

  However, the illumination device described in Patent Document 2 is not a two-lamp illumination configuration, and no description is given regarding the winding of the cable in the two-lamp illumination configuration. Patent Document 2 discloses a configuration in which a cable is rotated by 90 degrees, but the cable used here is not a flexible flat cable but a normal two-core cable.

  Furthermore, with respect to the wiring rotated 90 degrees, it is intended to complete the repulsive force when the harness is bent in the regulating member, and to prevent the influence of the stress on the other coiling parts. It is not configured to solve the problem of increasing the size of the machine by securing the necessary space.

  The present invention has been made to solve such a problem. In an image reading apparatus having a configuration in which an illuminating device is disposed facing the reading optical axis in the sub-scanning direction, the flexible flat cable is wound around. An object of the present invention is to provide an image reading apparatus and an image forming apparatus capable of downsizing the apparatus.

In order to achieve the above object, an image reading apparatus according to the present invention includes a first mirror unit that includes a plurality of illumination devices that irradiate a document, and a second mirror that travels at a half speed relative to the first mirror unit. In the image reading apparatus provided with a flexible flat cable for supplying power to the unit, the first mirror unit, and the illuminating device, the illuminating device is disposed facing the reading optical axis in the sub-scanning direction. A substrate having a connector at one end in the main scanning direction, a plurality of light sources arranged on the substrate in the main scanning direction, a light guide for guiding light from the light source to a reading object, the substrate, and the light guide A bracket fixed on the first mirror unit, and the flexible flat cable is connected to the image reading device from a power supply board for supplying power to the illumination device. Main scanning direction passes through the center of, and of the street along the lower the sub-scanning direction of the first mirror unit, the light from said light source through the upper portion traveling around a lower portion of the second mirror unit The first mirror unit is configured with one wiring without branching so as not to block, and is branched to a plurality of wirings at a branching portion located on the first mirror unit and connected to each lighting device, At least one wiring after branching is characterized in that the direction of the wiring is bent 90 degrees upward in the vertical direction between the branch portion and the lighting device.

  According to the present invention, in an image reading device having a configuration in which the illumination device is disposed facing the reading optical axis in the sub-scanning direction, the size of the device can be reduced by the configuration of the flexible flat cable.

1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention. 1 is a cross-sectional view of an image reading apparatus according to an embodiment of the present invention as viewed from a main scanning direction. It is a perspective view of the illuminating device used for the image reading apparatus which concerns on embodiment of this invention. FIG. 3 is a cross-sectional view of the image reading apparatus according to the embodiment of the present invention when the illumination device is mounted and viewed from the main scanning direction. It is sectional drawing which looked at the state before bending the flexible flat cable of the image reading apparatus which concerns on embodiment of this invention from the upper surface. 1 is a perspective view of an image reading apparatus according to an embodiment of the present invention. It is sectional drawing which looked at the state after bending the flexible flat cable of the image reading apparatus which concerns on embodiment of this invention from the upper surface. It is a perspective view of the illuminating device used for a general image reading apparatus. It is sectional drawing which mounted the illuminating device in the general image reading apparatus, and was seen from the main scanning direction. It is sectional drawing which looked at the state which wound the flexible flat cable in the general image reading apparatus from the upper surface.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, an image forming apparatus 1 according to the present embodiment includes an apparatus main body 1M having a paper feed section 2, an image forming section 3, and an image reading apparatus 4, and an automatic document arranged on the apparatus main body 1M. This is a digital multi-function machine including a transport unit (ADF) 5.

  The paper feeding unit 2 includes a plurality of stages of paper feeding cassettes 21A, 21B, and 21C that can store cut sheet-like transfer papers P in a stacked state. In each of the paper feeding cassettes 21A, 21B, and 21C, for example, transfer paper P (for example, white paper) having a sheet size selected in advance from a plurality of sheet sizes is accommodated in the vertical or horizontal paper feeding direction. ing.

  The paper feeding unit 2 includes paper feeding devices 22A, 22B, and 22C that sequentially pick up and separately transfer the transfer paper P stored in the paper feeding cassettes 21A, 21B, and 21C from the uppermost layer side. The paper feeding unit 2 is further provided with various rollers 23 and the like. By these, the transfer paper P fed from the paper feeding devices 22A, 22B, and 22C is transferred to a predetermined image forming position of the image forming unit 3. A sheet feeding path 24 is formed to convey the sheet.

  The image forming unit 3 includes an exposure device 31, photosensitive drums 32K, 32Y, 32M, and 32C, and a developing device filled with black (K), yellow (Y), magenta (M), and cyan (C) toners. 33K, 33Y, 33M, and 33C. The image forming unit 3 includes a primary transfer unit 34, a secondary transfer unit 35, and a fixing unit 36.

  For example, the exposure device 31 generates the laser light L for exposure of each color based on the image read by the image reading device 4. Further, the exposure device 31 exposes the photosensitive drums 32K, 32Y, 32M, and 32C of the respective colors with laser light, and the static layers of the respective colors corresponding to the read images on the surface layer portions of the photosensitive drums 32K, 32Y, 32M, and 32C. An electrostatic latent image is formed.

  The developing devices 33K, 33Y, 33M, and 33C supply the thin-layer toner to the corresponding photosensitive drums 32K, 32Y, 32M, and 32C, respectively, and develop the electrostatic latent image with the toner. Is supposed to do.

  The image forming unit 3 primarily transfers the toner image developed on the photosensitive drums 32K, 32Y, 32M, and 32C to the primary transfer unit 34, and the toner image is transferred to the secondary transfer unit 35 adjacent to the primary transfer unit 34. Secondary transfer is performed on the transfer paper P. Further, the image forming unit 3 heats and pressurizes the toner image secondarily transferred onto the transfer paper P and melts it, and fixes the color image on the transfer paper P for recording.

  The image forming unit 3 has a transport path 39A for transporting the transfer paper P carried from the paper feed unit 2 through the paper feed path 24 to the secondary transfer unit 35 side. In the transport path 39A, first, the transport timing and transport speed of the transfer paper P are adjusted by the registration roller pair 37. The transfer sheet P passes through the secondary transfer unit 35 and the fixing unit 36 in synchronization with the belt speed at the primary transfer unit 34 and the secondary transfer unit 35 and is then discharged onto the discharge tray 38. It is like that.

  The image forming unit 3 also has a manual paper feed path 39B that feeds transfer paper (not shown) placed on the manual feed tray 25 to the transport path 39A upstream of the registration roller pair 37. ing.

  Below the secondary transfer unit 35 and the fixing unit 36, a switchback conveyance path 39C and a reverse conveyance path 39D each including a plurality of conveyance rollers and conveyance guides are disposed.

  When forming an image on both sides of the transfer paper P, the switchback transport path 39C moves backward after moving the transfer paper P on which one side of the image has been fixed from one end (moves in the opposite direction to the time of entry). ) To carry out switchback.

  The reverse conveyance path 39D reverses the front and back of the transfer paper P that is switched back by the switchback conveyance path 39C, and feeds the paper again to the registration roller pair 37.

  The transfer paper P that has been subjected to the image fixing process on one side by the switchback conveyance path 39C and the reverse conveyance path 39D is reversed in its forward and reverse directions, and again enters the secondary transfer nip. . The transfer paper P is discharged onto the paper discharge tray 38 after the secondary transfer processing and fixing processing of the image are performed on the other surface.

  Next, details of the image reading apparatus 4 will be described with reference to FIG.

  The image reading device 4 includes a first mirror unit 203 including illumination devices 300a and 300b and a first mirror 202 supported at both ends, and a second mirror 204 and a third mirror 205 supported at both ends. A second mirror unit 206 is provided, and an optical lens 207 that forms an image of reflected light of the document on an image sensor 208 such as a CCD.

  The first mirror unit 203 travels in the image reading device 4 at a constant speed in the sub-scanning direction. The second mirror unit 206 travels following the first mirror unit 203 at half the speed of the first mirror unit 203, so that the document on the document reading glass 209 is optically scanned.

  The illumination devices 300a and 300b are provided on the first mirror unit 203 so as to face each other with the reading optical axis interposed therebetween. The illumination devices 300a and 300b irradiate the document on the document reading glass 209, and the reflected light image is guided to the optical lens 207 via the first mirror 202, the second mirror 204, and the third mirror 205, and the optical lens 207 As a result, an image is formed on the image sensor 208. Here, the path of the reflected light indicated by the dotted line in the figure is hereinafter referred to as a reading optical axis.

  The image sensor 208 photoelectrically converts the reflected light image of the imaged document into an analog image signal, and reads the document. This mechanism may be a unit type in which the mirror and the image sensor are integrated, or a 1 × magnification sensor (CIS).

  When the sheet original is automatically read continuously, the automatic original conveying unit 5 conveys the original onto the sheet original reading glass 210, and a reflected light image passing through the sheet original reading glass 210 is formed on the image sensor 208. The At that time, the first mirror unit 203 and the second mirror unit 206 are fixed and read the image of the conveyed sheet original. On the other hand, when reading a book document, the automatic document transport unit 5 is opened once, the book document is set on the document reading glass 209, and then the automatic document transport unit 5 is closed. The booklet can be held by the pressed platen. These reading operations are started when a start key provided on the operation unit of the image reading device 4 is pressed.

  The automatic document feeder 5 is connected to the upper part of the apparatus main body 1M of the image forming apparatus 1 through a hinge mechanism so as to be opened and closed. The automatic document feeder 5 is rotated between an open position where the document reading glass 209 and the sheet document reading glass 210 are exposed in the image reading device 4 and a closed position where the document reading glass 209 and the sheet document reading glass 210 are covered. It has come to be.

  The automatic document feeder 5 is configured as a sheet-through type automatic document feeder. The automatic document transport unit 5 includes a document table 51 that is a document placement table, a document transport unit 52 including various rollers and guide members, and a document discharge tray 53 that stacks document sheets S after image reading. Yes.

  FIG. 3 shows an illumination device 300 mounted on the image reading device 4. The lighting device 300 includes an LED substrate 302, an LED chip 301, a light guide 306, and a bracket 303.

  A plurality of LED chips 301 as light sources are arranged on the LED substrate 302 in the main scanning direction, and are fixed by brackets 303 using screws 305. A connector 304 for connecting a flexible flat cable 214 for supplying power to the first mirror unit 203 and the illumination device 300 is disposed at one end of the LED substrate 302 in the main scanning direction. Further, as will be described later, a light guide 306 and a cover 307 are also provided for guiding and diffusing light from the light source in the direction of the reading target.

  FIG. 4 is a cross-sectional view of the image reading apparatus 4 according to this embodiment in which the illumination device 300 is mounted as viewed from the main scanning direction. The illuminating devices 300a and 300b are arranged on the first mirror unit 203 so as to face each other with the reading optical axis in the sub-scanning direction. The illuminating device 300a and the left side are arranged on the right side of the reading optical axis. The lighting device 300b is arranged. In this embodiment, the two lighting devices 300a and 300b are used as the lighting device, but the number of lighting devices is not limited to this.

  In addition to the LED chip 301, LED substrate 302, bracket 303, connector 304, and screw 305 shown in FIG. 3, the illumination devices 300a and 300b include light guides 306a and 306b and covers 307a and 307b, respectively.

  The light guides 306a and 306b guide light emitted from the LED chips 301a and 301b to reading positions, respectively. The covers 307a and 307b are attached to the LED boards 302a and 302b via the brackets 303a and 303b, and are provided outside the light guides 306a and 306b as members that shield light from the outside. The brackets 303a and 303b fix the LED substrates 302a and 302b and the light guides 306a and 306b on the first mirror unit 203.

  The flexible flat cable 214 connects the power supply board 217 of the power supply source and the lighting devices 300a and 300b, and supplies power to the lighting devices 300a and 300b. The flexible flat cable 214 passes from the power supply board 217 to the left in the sub-scanning direction, below the first mirror unit 20, and from the lower part of the second mirror unit 206 to the right in the sub-scanning direction via the upper part. Connected to lighting devices 300a and 300b.

  The flexible flat cable 214 is configured by one wiring without branching from the power supply substrate 217 through the center portion in the main scanning direction in the image reading apparatus 4 to the first mirror unit 203 via the second mirror unit 206. Has been.

  The flexible flat cable 214 includes a branch portion 214c that branches into a plurality of wires. The branching portion 214c is located on the front side of the reading optical axis when viewed from the left side in the sub scanning direction on the first mirror unit 203. The flexible flat cable 214 is branched into two wires at the branching portion 214c and connected to the lighting devices 300a and 300b. In the present embodiment, the flexible flat cable 214 is branched into two wires at the branch portion 214c, but may be branched into two or more wires.

  The problem of turning the cable in the image reading device 4 will be described with reference to FIG. FIG. 5 is a top view showing a state before the flexible flat cable 214 is bent in the vertical direction when the flexible flat cable 214 is turned in the image reading apparatus 4 according to the present embodiment.

  The flexible flat cable 214 is divided into two branches 14a and 14b at a branching portion 214c on the first mirror unit 203 and is wired to each of the lighting devices 300a and 300b. The illumination device 300a is disposed on the opposite side (right side) of the reading optical axis when viewed from the left side in the sub-scanning direction, and the illumination device 300b is disposed on the front side (left side) of the reading optical axis.

  When the flexible flat cable 214 is connected to the connector 304a of the lighting device 300a, the flexible flat cable 214a has a layout around the lighting device 300a. Here, since the flexible flat cable 214a has a width, a space must be provided between the flexible flat cable 214a and the side surface 216 of the scanner base in order to rotate the flexible flat cable 214a. There is a problem that becomes large.

  FIG. 6A is a perspective view of the first mirror unit 203 in a state before the flexible flat cable 214 is bent as in FIG. In contrast, FIG. 6B is a perspective view of the first mirror unit 203 in a state after the flexible flat cable 214 is bent.

  In the first mirror unit 203 in the image reading apparatus 4 according to the present embodiment, the wiring portion 214d on the side surface of the flexible flat cable 214a that goes around the side surface of the first mirror unit 203 is bent 90 degrees in the vertical direction (vertically upward). The connector 304a is connected. Since the flexible flat cable 214 has almost no thickness, it is not necessary to provide a space for wiring between the first mirror unit 203 and the scanner base side surface 216 by adopting a configuration in which the cable is wound around in this way. For this reason, the influence of the wiring layout of the flexible flat cable 214 on the machine size is eliminated. The thickness of the flexible flat cable 214 is, for example, 1 mm or less.

  FIG. 7 is a top view of the image reading device 4 when the cable twisting configuration in the present embodiment shown in FIG. 6 is applied. As shown in FIG. 7, after the flexible flat cable 214a is bent, a space for turning the flexible flat cable 214a between the first mirror unit 203 and the scanner base side surface 216 is made wider than before the flexible flat cable 214a is bent. There is no need.

  In the present embodiment, the cable that is bent 90 degrees upward in the vertical direction is only the flexible flat cable 214a that is the side that is routed around the side surface of the first mirror unit 203. That is, the flexible flat cable 214a connected to the illumination device 300a on the opposite side of the reading optical axis with respect to the branching portion 214c when viewed from the sub-scanning direction is bent. As for the flexible flat cable 214b branched at the branching portion 214c, the connector 304b to which the flexible flat cable 214b is connected is on the left side of the reading optical axis (see FIGS. 5 and 7), and it is not necessary to wrap around the side surface of the first mirror unit 203. It is.

  As described above, in the image reading apparatus 4 according to the present embodiment, the flexible flat cable 214 extends from the power supply substrate 217 for supplying power to the illumination devices 300a and 300b in the central portion in the main scanning direction of the image reading apparatus 4. As described above, the first mirror unit 203 via the second mirror unit 206 is not branched and is constituted by one wiring.

  Further, a branching portion 214c located on the first mirror unit 203 branches to the flexible flat cable 214a and the flexible flat cable 214b and is connected to the lighting devices 300a and 300b. After branching, the flexible flat cable 214a is illuminated from the branching portion 214c. The direction of the wiring is bent 90 degrees vertically upward until the device 300a.

  With this configuration, it is not necessary to make a space for turning the flexible flat cable 214a between the first mirror unit 203 and the scanner base side surface 216, so that the apparatus can be miniaturized.

  Of the wiring of the flexible flat cable 214, the wiring that is bent 90 degrees upward in the vertical direction is connected to the illumination device 300a on the opposite side of the reading optical axis with respect to the branching portion 214c when viewed from the sub-scanning direction. It may be 214a.

  With this configuration, only the flexible flat cable 214a on the side that affects the machine size is bent upward in the vertical direction, so that an unnecessary bent portion is not formed, and the turning is not complicated. Can do.

  Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention.

  According to the present invention, in the image reading device having the configuration in which the illumination device is disposed facing the reading optical axis in the sub-scanning direction, the size of the device can be reduced by the configuration of the flexible flat cable that is wound around. It is useful for general apparatuses and image forming apparatuses.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 4 Image reader 203 1st mirror unit 206 2nd mirror unit 214 Flexible flat cable 214c Branch part 217 Power supply board 300a, 300b Illuminating device 301 LED chip (light source)
302a, 302b LEC substrate (substrate)
303a, 303b Bracket 304a, 304b Connector 306a, 306b Light guide

Japanese Patent No. 4527320 Japanese Patent No. 433318

Claims (3)

A first mirror unit having a plurality of illumination devices for irradiating a document, a second mirror unit that travels at a half speed relative to the first mirror unit, the first mirror unit, and the illumination device for supplying power In an image reading apparatus comprising a flexible flat cable, wherein the illuminating device is arranged facing the sub-scanning direction across the reading optical axis,
The illumination device includes a substrate having a connector at one end in the main scanning direction, a plurality of light sources arranged on the substrate in the main scanning direction, a light guide for guiding light from the light source to a reading object, the substrate, and the light guide. A bracket for fixing the light body on the first mirror unit,
The flexible flat cable passes from the power supply substrate for supplying power to the illumination device through the center in the main scanning direction of the image reading device , and passes under the first mirror unit along the sub-scanning direction. The first mirror unit is configured with a single wiring without branching so as not to block light from the light source via the upper part through the lower part of the second mirror unit ,
A branch part located on the first mirror unit branches to a plurality of wirings and is connected to each lighting device, and after branching, at least one of the wirings has a vertical direction between the branching part and the lighting device. An image reading apparatus bent upward by 90 degrees.   The wiring that is bent 90 degrees upward in the vertical direction among the wirings is a wiring that is connected to the illuminating device on the opposite side of the reading optical axis with respect to the branch portion when viewed from the sub-scanning direction. The image reading apparatus according to 1.   An image forming apparatus comprising the image reading apparatus according to claim 1.

Images