JP2021027478A - Flat cable and electronic device - Google Patents

Abstract

To provide a flat cable capable of reducing the generation of a radiation noise while capable of miniaturizing a device to be installed.SOLUTION: A flat cable 1081 having: terminal parts 108a and 108b; and a plurality of conductor wires containing first and second conductor wires conducting the terminal parts 108a and 108b, includes: a first region 301; a second region 302; a slit SL provided between the first region 301 and the second region 302; and a shield SD2 adhered onto one surface of the second region 302, and reducing a flow of an electromagnetic field.SELECTED DRAWING: Figure 4

Description

The present invention relates to a flat cable having a plurality of conductor wires and an electronic device including the same.

Generally, there is known an image reading device that irradiates an image or character information recorded on a document with light and reads the reflected light by an imaging unit including an image sensor. In such an image reading device, the original is placed on the platen glass with the scanning surface facing downward, and the image pickup unit arranged below the platen glass moves to read the image and character information of the original.

Conventionally, an image reader equipped with a flexible flat cable (hereinafter referred to as FFC) for movably accommodating an LED lamp that irradiates a document with light and connecting a control board built in the apparatus main body and the LED lamp has been used. It has been proposed (see Patent Document 1). The FFC transmits a control signal to the LED lamp while bending as the LED lamp moves, and slides on the bottom surface of the frame of the image reading device when bending.

Further, an image reading device including a document mounting glass and a traveling body equipped with a CIS for reading an image of a document mounted on the document mounting glass has been proposed (see Patent Document 2). The traveling body is supported by a belt driven by a motor, and when reading an image of a document, the traveling body moves along the document by driving the motor. The image read by the CIS is transmitted to the control board of the image forming apparatus equipped with the image reader through the analog image signal transmission cable, the A / D converter, and the digital signal transmission cable. Further, the motor and the control board are connected by a drive signal transmission cable that transmits a drive signal to the motor.

Japanese Patent No. 5544276 Japanese Unexamined Patent Publication No. 2014-22776

Since the FFC described in Patent Document 1 slides on the bottom surface of the frame of the image reader when curved, strong stress is applied to the bent portion of the FFC when the LED lamp and the bottom surface of the frame are close to each other. There is a risk that the electric wire in the FFC will be broken. Therefore, it is necessary to increase the distance between the LED lamp and the bottom surface of the frame to some extent, which causes a problem that the device becomes large.

Therefore, as in Patent Document 2, the cables are divided into a plurality of cables, the width of each cable is reduced, and the analog image signal transmission cable bent by the movement of the traveling body is particularly provided along the side surface of the frame of the image reader. It is conceivable to arrange them. However, the digital signal transmission cable and the drive signal transmission cable are crawled separately in the device, so that the space for crawling the cable increases and the number of connectors for connecting the cables also increases. It ends up. Therefore, there is a problem that the device becomes large in the end.

Then, as in Patent Document 2, if the cables are divided into a plurality of cables and the space for crawling the cables is reduced, the cables will overlap, and the signals will interfere with each other and radiate at the overlapped portions. Noise may occur.

Therefore, an object of the present invention is to provide a flat cable and an electronic device capable of reducing the generation of radiation noise while enabling the miniaturization of the device to be installed.

One aspect of the present invention includes a first terminal portion, a second terminal portion, and a plurality of conductor wires including a first conductor wire and a second conductor wire conducting the first terminal portion and the second terminal portion thereof. In a flat cable having, a first region including the first conductor wire, a second region including the second conductor wire, and a slit provided between the first region and the second region. , A flat cable characterized by having a first shield member attached to one surface of the second region and reducing the flow of an electromagnetic field.

According to the present invention, when at least a part of the first region is superposed on one surface of the second region when viewed from the thickness direction of the flat cable by using the slit, the first shield member is overlapped with the first region. It can be interposed in the overlapping portion with the two regions. Therefore, the device on which the flat cable is installed can be miniaturized, and the generation of radiation noise can be reduced.

(A) is an overall schematic view showing the printer according to the first embodiment, and (b) is a schematic view showing an image forming portion. The perspective view which shows the image reading part when the reading part is in a home position. A control block diagram showing control in a printer. (A) is a front view showing the FFC according to the first embodiment, (b) is a rear view showing the FFC according to the first embodiment, and (c) is an FFC according to the first embodiment. A front view showing a folded and overlapped state. (A) is a front view showing the FFC according to the second embodiment, (b) is a rear view showing the FFC according to the second embodiment, and (c) is an FFC according to the second embodiment. A front view showing a folded and overlapped state. (A) is a front view showing the FFC according to the third embodiment, (b) is a rear view showing the FFC according to the third embodiment, and (c) is A- in (a) and (b). A sectional view taken along the arrow. (A) is a front view showing the FFC according to the fourth embodiment, (b) is a rear view showing the FFC according to the fourth embodiment, (c) is A- in (a) and (b). A sectional view taken along the arrow. (A) is a front view showing the FFC according to the fifth embodiment, (b) is a rear view showing the FFC according to the fifth embodiment, (c) is an A- in (a) and (b). A sectional view taken along the arrow.

<First Embodiment>
[overall structure]
Hereinafter, embodiments according to the present invention will be described with reference to the drawings. FIG. 1A is a diagram showing a printer 1 as an image forming apparatus according to the first embodiment. As shown in FIG. 1A, the printer 1 includes a device main body 2 and an image reading device 3 provided on the upper part of the device main body 2, and forms an image on a sheet inside the device main body 2. An image forming unit 10 is provided.

As shown in FIG. 1B, the image forming unit 10 includes an electrophotographic image forming unit PU and a fixing device 17. When the start of the image forming operation is commanded in the image forming unit PU, the photosensitive drum 11 which is a photoconductor rotates, and the drum surface is uniformly charged by the charging device 12. Then, the exposure device 13 modulates and outputs the laser beam based on the image data transmitted from the image reading device 3 or an external computer, scans the surface of the photosensitive drum 11, and forms an electrostatic latent image. This electrostatic latent image is visualized (developed) by the toner supplied from the developing device 14 to become a toner image.

In parallel with such an image forming operation, a feeding operation of feeding a sheet loaded on a cassette or a manual feed tray (not shown) toward the image forming unit 10 is executed. The fed sheet is conveyed in accordance with the progress of the image forming operation by the image forming unit PU. Then, the toner image supported on the photosensitive drum 11 is transferred to the sheet by the transfer roller 15. The toner remaining on the photosensitive drum 11 after the toner image transfer is recovered by the cleaning device 16. The sheet on which the unfixed toner image is transferred is delivered to the fixing device 17, sandwiched between roller pairs, and heated and pressurized. The sheet in which the toner is melted and fixed to the sheet and the image is fixed is discharged by the discharge rollers and the like.

[Image reader]
Next, the configuration of the image reading device 3 will be described in detail. In the present embodiment, the sheet includes, in addition to plain paper, special paper such as coated paper, recording material having a special shape such as envelope and index paper, and plastic film or cloth for overhead projectors. It includes. The manuscript is also an example of a sheet, and the manuscript may be a blank sheet or may have an image formed on one side or both sides.

As shown in FIG. 1A, the image reading device 3 includes an image reading unit 5 as an electronic device for reading an image of a document, and an automatic document transporting device (hereinafter, an automatic document transporting device) provided to be openable and closable with respect to the image reading unit 5. , Simply referred to as ADF) 4. The image reading unit 5 includes a platen glass 70 on which a document is placed and transmits light, and a reading unit 105 as a first electronic device and a reading unit for reading an image of the document. The image reading unit 5 is configured to be capable of reading a document by two types of methods called fixed reading and scanning. The reading unit 105 is configured to be movable in the sub-scanning direction (arrow X direction in FIG. 1A) by a motor 213 (see FIG. 3) that drives a belt (not shown) that supports the reading unit 105.

In the fixed reading, the image reading unit 5 records the document placed on the platen glass 70 as the sheet support by scanning the scanning unit 105 at a constant speed in the sub-scanning direction. The image information is read line by line. Further, in the scanning, the reading unit 105 is moved so as to come to the center position of the lead roller 49 of the ADF4, and the document on the document tray 41 conveyed by the ADF4 is optically read.

The ADF 4 includes a document tray 41 for loading a document bundle S composed of one or more documents, a feeding roller 43, a separation pad 45, and a separation roller 44. The feeding roller 43 is configured to be able to move up and down via an arm, and by descending from a retracted position located above, the feeding roller 43 comes into contact with the uppermost document of the document bundle S loaded on the document tray 41 and is fed. It is configured to send. The originals fed by the feeding roller 43 are separated and fed one by one by the action of the separation roller 44 and the separation pad 45.

The document separated by the separation roller 44 and the separation pad 45 is conveyed to the registration roller pair 47 by the extraction roller 46, and the document is abutted against the registration roller pair 47. As a result, the original is formed in a loop-like deflection, and the skew in the conveying of the original is corrected. On the downstream side of the registration roller pair 47, a transport path for transporting the document passing through the registration roller pair 47 to the scanning glass 57 is arranged, and the document sent to this transport path is read by the upstream roller. It is conveyed to the image reading position by 48. At the image scanning position, the surface of the document is illuminated by the LED 204 (see FIG. 3) mounted on the scanning unit 105, and the reflected light is guided by the image sensor 207 (see FIG. 3) of the scanning unit 105 to guide the surface of the document. The image is read line by line. As the image sensor 207, for example, a CIS (Contact Image Sensor) or a CCD (Charged Coupled Devices) is applied.

A reading downstream roller 50 is provided downstream of the lead roller 49 in the document conveying direction, and the document conveyed by the reading downstream roller 50 is a paper ejection tray by the paper ejection roller 56 when only the surface image of the original is read. It is discharged to 51. When there are a plurality of originals on the original tray 41, the image reading device 3 repeats the above process until the final original is read and the paper is discharged to the paper ejection tray 51.

On the other hand, when the back image of the original is also read, the front image is read and the original is stopped before the rear end of the original passes through the paper ejection roller 56. Then, by rotating the paper ejection roller 56 in the reverse direction, the original is conveyed toward the registration roller pair 47 via the double-sided transfer path 58, and the original is conveyed in the same manner as when reading the front image, thereby conveying the back surface of the original. Can be read.

As shown in FIG. 2, a printed circuit board 205 on which an image sensor 207 (see FIG. 3) is mounted is mounted on the reading unit 105, and the printed circuit board 205 is equipped with a flexible flat cable (hereinafter, FFC) 108. One end of is connected. The FFC 108 crawls along the side surface 109a of the frame 109 of the image reading unit 5 and is guided to the outside of the image reading unit 5 from the hole 110 formed in the side surface 109a to serve as a second electronic device and a control unit. It is connected to the controller 200 (see FIG. 3).

At the time of fixed reading, the reading unit 105 reads the image of the original placed on the platen glass 70 while moving from the home position shown in FIG. 2 (in the direction of arrow X in FIG. 1A). At this time, the FFC 108 is curved in the horizontal direction and moves together with the reading unit 105 while sliding on the side surface 109a of the frame 109. However, since the FFC 108 is supported by the side surface 109a, the FFC 108 is less likely to hang down due to gravity. ing. The FFC 108 does not have to be curved in the horizontal direction, but may be configured to be curved in the horizontal direction.

[Control block]
FIG. 3 is a control block diagram according to the present embodiment. The controller 200 provided in the image reading device 3 (or the main body of the printer 1) is connected to an operation unit 203 and a reading unit 105 that support the user to specify the size of the document, start scanning, and the like. The controller 200 includes a CPU 201 that is a central processing unit of the image reading device 3, a non-volatile memory 202 that stores a control program of the CPU 201, an FFC connector 210, a power supply unit 211, and an image processing unit 212. ing.

The reading unit 105 includes an LED 204 as a light source for irradiating a document with light, and a printed circuit board 205. The printed circuit board 205 has an LED drive unit 206 that controls lighting of the LED 204, an image sensor 207 as an image pickup unit that receives light reflected by the sheet, an AFE 208 as a conversion unit, and an FFC connector 209. .. The reading unit 105 and the controller 200 are electrically connected by connecting the FFC 108 between the FFC connectors 209 and 210. The AFE (Analog Front End) 208 converts an analog image signal output from the image sensor 207 into digital image data.

[Image reading operation]
Next, the operations of the controller 200 and the reading unit 105 during fixed reading will be described. As shown in FIG. 3, when a read job start instruction is issued from the operation unit 203, the CPU 201 controls the power supply unit 211 to output the + 24V and + 5V voltages to the power supply unit.

The + 24V voltage output by the power supply unit 211 is supplied to the LED drive unit 206 via the FFC connectors 209, 210 and FFC 108, and the LED 204 lights up. Further, the + 5V voltage output by the power supply unit 211 is supplied to the image sensor 207 and AFE208 via the FFC connectors 209, 210 and FFC 108. Then, the CPU 201 executes serial communication to the AFE 208 via the FFC connectors 209 and 210 and the FFC 108. The AFE208 outputs a read start signal and a drive signal to the image sensor 207 by making predetermined settings in an internal register by serial communication. As a result, the driving of the image sensor 207 is started, and the A / D conversion by the AFE 208 is started.

In this state, the CPU 201 drives the motor 213 to move the reading unit 105 in the sub-scanning direction, and the reading unit 105 scans the document on the platen glass 70 while moving in the sub-scanning direction. The image sensor 207 outputs the image signal of the scanned document to the AFE208, and the AFE208 converts the image signal output from the image sensor 207 into digital image data by setting a predetermined register by the serial signal. .. The image data is transmitted to the image processing unit 212 of the controller 200 by the FFC connectors 209, 210 and FFC 108, and the image processing unit 212 executes predetermined image processing such as shading correction to the device main body 2 or an external PC or the like. Send image data.

Next, the CPU 201 determines whether or not the reading of the document by the reading unit 105 has been completed. While the scanning unit 105 is reading the document, the serial communication to the AFE208 is not performed, and the serial communication signal is fixed at the Hi or Low level.

When the reading of the original is completed, the AFE208 is subjected to a predetermined serial communication, so that the A / D conversion operation of the AFE208 is completed. Further, a predetermined serial communication is performed on the AFE 208, and the driving of the image sensor 207 ends. Then, the CPU 201 turns off the power supply unit 211, the power supply of + 24V and + 5V is stopped, and the motor 213 is also stopped. As a result, the reading job is completed.

[FFC configuration]
Next, the _{configuration of the FFC 108 1} according to the first embodiment will be described in detail. As shown in FIG. 4 (a) and (b), FFC108 ₁ has a terminal portion 108a which is connected to the FFC connectors 209 and 210 at both ends in the longitudinal direction, 108b are provided. Each of the terminal portion 108a as the first terminal portion and the 108b as the second terminal portion has a 50-core pin and a jacket covering the pin. The terminal portion 108a has a jacket on the back surface side of the pin, and the terminal portion 108b has a jacket on the front surface side of the pin. FFC108 ₁ of the terminal portion 108a, 108b is has a pin 50 core, FFC108 ₁ is 25 core first conductor capable of transmitting electrical signals or power supply voltage is at a position corresponding to the pin of the 26-pin th Does not have. The FFC 108 ₁ has a plurality of conductor wires CL (48 in the present embodiment) that are aligned in the width direction and conduct the pins of the terminal portions 108a and 108b to each other. These plurality of conductor wires CL are covered by being sandwiched from both sides by two resin films such as polyester film tape (see, for example, FIGS. 6 (c), 7 (c), and 8 (c)). ..

The FFC 108 ₁ has slits SL near the center in the width direction, that is, at positions corresponding to the 25th and 26th cores of the terminal portions 108a and 108b, and two conductors are used to form the slit SL. The line is pulled out. Further, the slit SL is arranged so as to be separated from each of the terminal portions 108a and 108b by a predetermined distance in the longitudinal direction. That is, although there is one FFC at both ends where the terminal portions 108a and 108b are present, the slit SL portion is divided into two FFCs. These two FFCs are referred to as a first region 301 and a second region 302, respectively. In short, the first region 301 includes 24 conductor wires CL including a first conductor wire CL1 for transmitting a signal and a ground conductor wire CL which is a ground (grounded state). Further, the second region 302 includes 24 conductor wires CL including a second conductor wire CL2 for transmitting a signal and a ground conductor wire serving as a ground. In the present embodiment, for example, the first conductor wire CL1 is a conductor wire for transmitting a serial communication signal, and the second conductor wire CL2 is a conductor wire for transmitting an image data signal (see FIG. 3). ).

_{Then, as shown in FIG. 4A, the FFC 108 1} according to the first embodiment is provided on the surface (one surface) of the second region 302 as a second shield member for reducing the flow of the electromagnetic field. Shield SD2 is attached. Further, as shown in FIG. 4B, a shield SD1 as a first shield member for reducing the flow of the electromagnetic field is attached to the back surface (the other surface) of the first region 301. These shields SD1 and SD2 are made of a conductive member and are arranged so as to be located outside of both ends of the slit SL in the longitudinal direction. Further, as the shields SD1 and SD2, in the present embodiment, shield tapes (for example, copper foil tape or the like) as an electromagnetic shield containing a sheet metal made of a conductive member are used. However, the present invention is not limited to this, and the conductive material may be a mesh-like material or a material using foamed metal.

When manufacturing FFC108 ₁ , a plurality of conductor wires are arranged in a state where two conductor wires in the center are pulled out in advance, the conductor wires are sandwiched between resin films from above and below, and heat and pressure are applied to bond the resin films. After that, _{the central portion of the FFC 108 1} without a conductor is cut with a member having a sharp tip such as a needle to open a slit SL. After that, the shield SD2 is attached to the front surface of the second region 302, and the shield SD1 is attached to the back surface of the first region 301.

[FFC arrangement]
Next, _{the arrangement of FFC108 1} will be described. First, by folding at the mountain fold or valley fold position in the first region 301 and the second region 302 of the _{FFC 108 1} shown in FIGS. 4 (a) and 4 (b), the first region is as shown in FIG. 4 (c). The 301 and the second region 302 are overlapped. That is, a part of the back surface of the first region 301 and a part of the front surface of the second region 302 are overlapped so as to face each other. Thus, the first region 301 and second region 302, when viewed from the thickness direction of the FFC108 _1, at least partially overlap, in FFC108 ₁ at both ends in the longitudinal direction, do not overlap in the thickness direction. Further, the terminal portion 108a side of the first region 301 and the second region 302 are respectively folded diagonally. The width of the FFC 108 ₁ folded in this way is halved at the portion where the first region 301 and the second region 302 are overlapped.

Then, as shown in FIG. 2, the printed circuit board 205 (see FIG. 3) is attached to the side surface of the reading unit 105, and _{the terminal portion 108b of the FFC 108 1} is connected to the FFC connector 209 (see FIG. 3). Further, the FFC 108 ₁ is arranged from the side surface of the reading unit 105 along the side surface 109a of the frame 109 of the image reading unit 5, and is connected to the FFC connector 210 of the controller 200 through the hole 110.

As shown in FIG. 2, when the reading unit 105 is in the home position, the FFC 108 ₁ is supported by the side surface 109 a, so that the FFC 108 ₁ hangs down is reduced. However, when the reading unit 105 is located at the end position, _{the contact area between the FFC 108 1} and the side surface 109a is small, and most of the overlapping portion of the first region 301 and the second region 302 floats in the air. ing. Therefore, the FFC 108 ₁ tends to hang down due to gravity.

However, since the FFC 108 ₁ is folded so that the first region 301 and the second region 302 overlap each other using the slit SL, the width of the floating portion of _{the FFC 108 1 is halved.} Therefore, even if the FFC 108 ₁ hangs down due to gravity, the FFC 108 ₁ can be crawled in a space-saving manner without the _{FFC 108 1} coming into contact with the bottom surface 109 b of the frame 109. Further, the height of the image reading unit 5 can be reduced by the amount that the width of the FFC 108 _{1 is halved.} Since the _{slit SL is inserted in the center of one} FFC 108 1 and overlapped, the number of FFC connectors 209 and 210 does not increase as compared with the case where two FFCs are used, and the image reading unit 5 is costly. It can be downsized and miniaturized.

_{In the FFC 108 1 that} is folded using the slit SL as described above, the shields SD1 and SD2 are placed between the first region 301 and the second region 302 in the folded state, specifically, the surface of the second region 302. Is arranged between the surface and the back surface of the first region 301. That is, since the shields SD1 and SD2 are located so as to straddle the outside of the slit SL in the longitudinal direction, there is no portion between the first region 301 and the second region 302 without the shields SD1 and SD2. .. Then, as shown in FIG. 3, a signal current such as a DC power supply current having a voltage of + 24 V or + 5 V, a serial communication signal, or an image data signal flows through the FFC 108 _1. However, by arranging the shields SD1 and SD2, it is possible to block mutual interference between the first region 301 and the second region 302 and reduce the generation of radiation noise.

<Second Embodiment>
Next, a second embodiment in which the first embodiment is partially modified will be described with reference to FIGS. 5A, 5B, and 5C. In the description of the second embodiment, the same parts as those of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

The FFC 108 ₂ according to the second embodiment omits the shield SD2 as compared with the FFC 108 _{1 according} to the first embodiment, and is shown in FIGS. 5 (a) and 5 (b). The shield SD1 is attached only to the back surface of the first region 301. _{Also in the FFC 108 2} configured in this way, the shield SD1 is arranged between the first region 301 and the second region 302 in a state where the first region 301 and the second region 302 are overlapped. Therefore, it is possible to block the interference of the DC power supply current and the signal current and reduce the generation of radiation noise. Further, in the second embodiment, since the shield SD1 is sufficient, it is possible to prevent an increase in cost as compared with the first embodiment.

Since the other configurations, actions, and effects in the second embodiment are the same as those in the first embodiment, the description thereof will be omitted.

<Third embodiment>
Subsequently, a third embodiment in which the first embodiment is partially modified will be described with reference to FIGS. 6A, 6B, and 6C. In the description of the third embodiment, the same parts as those of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIGS. 6 (a) and 6 (b), the FFC 108 ₃ according to the third embodiment is compared with the FFC 108 _{1 according} to the first embodiment, and the conductive tapes CT1 and CT1 The CT2 is arranged. The conductive tapes CT1 and CT2 are connected to pins (ground terminals) that are conductive to the ground conductor wires of the terminal portions 108a and 108b. In particular, shield SD1, SD2, the terminal portions 108a at both ends, respectively, are morning affixed to the surface or back surface of FFC108 ₃ to exist a gap B with respect to 108b. Conductive tape CT1 is, in the surface of the FFC108 _3, are attached on position FFC108 ₃ surface that connects the gap B between the end of the terminal portion 108a and the shield SD2. The conductive tape CT1, when viewed from the thickness direction, are stacked in layers between the surface and the shield SD2 of FFC108 _3.

The conductive tape CT2, as shown in FIG. 6 (a) and 6 (b), In the back surface of FFC108 _3, position connecting the gap B between the end of the terminal portion 108b and the shield SD1 in which it affixed to the back surface of FFC108 _3. The conductive tape CT2, as shown in FIG. 6 (c), when viewed from the thickness direction, are layered between FFC108 ₃ of the back and the shield SD1.

As described above, the conductive tape CT1 is conducted to the pin conducting to the ground conductor wire of the terminal portion 108a and also to the shield SD2, that is, the shield SD2 is grounded (grounded). Similarly, the conductive tape CT2 is conducted to a pin conducting to the ground conductor wire of the terminal portion 108b and is also conducted to the shield SD1, that is, the shield SD1 is grounded (grounded). In this manner, the shield SD1, SD2 are ground can be provided a return path of the high-speed signals through conductor lines FFC108 ₃ to signal most recently. That is, the electric field / magnetic field created by the signal is closed internally by the return current in the opposite direction to the signal current and does not leak to the outside, so that radiation noise can be reduced.

<Fourth Embodiment>
Next, a fourth embodiment in which the third embodiment is partially modified will be described with reference to FIGS. 7A, 7B, and 7C. In the description of the fourth embodiment, the same parts as those of the first to third embodiments are designated by the same reference numerals, and the description thereof will be omitted.

In the FFC _{108 3} according to the third embodiment, the jacket of the terminal portion 108a is arranged on the back surface side, and the jacket of the terminal portion 108b is arranged on the front surface side. Therefore, it is necessary to attach the conductive tape CT1 conductive to the pin conducting the ground conductor wire to the front surface and the conductive tape CT2 to the back surface. On the other hand, the shield SD1 is attached to the back surface of the first region 301, and the shield SD2 is attached to the back surface of the second region 302. Then, the shield SD2 cannot be conducted to the terminal portion 108b, and the shield SD1 cannot be conducted to conduct to the terminal portion 108a, so that the effect of reducing radiation noise is low. If the jackets of both terminal portions 108a and 108b are arranged on the same surface side, for example, the jacket of the terminal portion 108b is arranged on the back surface side, either the shield SD1 or SD2 cannot be grounded. As a result, the effect of reducing radiation noise is also low.

Therefore, in the FFC 1084 according to the _fourth embodiment, as shown in FIGS. 7A, 7B, and 7C, one shield SD3 as the first shield member is the second shield SD3. It is bent from the front surface of the region 302 and attached to the back surface of the first region 301. By sticking the shield SD3 across the front surface and the back surface in this way, the shield SD3 conducts to the conductive tape CT1 at one end and to the conductive tape CT2 at the other end. That is, the end portion on the front surface of the shield SD3 on the terminal portion 108b side is short-circuited to the conductive tape CT2 on the back surface, and the end portion on the back surface of the shield SD3 on the terminal portion 108a side is short-circuited to the conductive tape CT1 on the front surface. Will be done. Thereby, the return path of the high-speed signals through conductor lines FFC108 ₄ without interruption at the end of the shield SD3, because it is ground, it is possible to enhance the effect of reducing the radiation noise.

<Fifth Embodiment>
Subsequently, the fifth embodiment, which is a partial modification of the third embodiment, will be described with reference to FIGS. 8 (a), 8 (b), and (c). In the description of the fifth embodiment, the same parts as those of the first to fourth embodiments are designated by the same reference numerals, and the description thereof will be omitted.

As described above, when the jacket of the terminal portion 108a is arranged on the back surface side and the jacket of the terminal portion 108b is arranged on the front surface side, the conductive tape CT1 conducting to the pin conducting to the ground conductor wire is placed on the front surface. The conductive tape CT2 needs to be attached to the back surface. On the other hand, the shield SD1 is attached to the back surface of the first region 301, and the shield SD2 is attached to the back surface of the second region 302. In this state, the shield SD2 cannot be conducted to the terminal portion 108b, and the shield SD1 cannot be conducted to conduct to the terminal portion 108a, so that the effect of reducing radiation noise is low. Similarly, for example, when the jackets of both terminal portions 108a and 108b are arranged on the same surface side, either the shield SD1 or SD2 cannot be grounded, which also has the effect of reducing radiation noise. Low.

Therefore, in the FFC 1085 according to the _fifth embodiment, as shown in FIGS. 8A, 8B, and 8C, the conductive tapes CT3 and CT4 straddle the front surface and the back surface. It is wound and pasted so as to go around. By sticking the conductive tapes CT3 and CT4 across the front surface and the back surface in this way, both ends of the shields SD1 and SD2 are electrically connected to the conductive tapes CT3 and CT4. That is, the ends of the shield SD1 and the shield SD2 on the terminal portion 108b side are short-circuited to the pins conducting the ground conductor wire on the surface of the conductive tape CT4 as the second conductive portion. Further, the ends of the shield SD1 and the shield SD2 on the terminal portion 108a side are short-circuited to a pin conducting the ground conductor wire on the back surface of the conductive tape CT3 as the first conductive portion. Thereby, the return path of the high-speed signals through conductor lines FFC108 _5, without interruption at the end of the shield SD1, SD2, since the ground, it is possible to enhance the effect of reducing the radiation noise.

<Possibilities of other embodiments>
In the first to fifth embodiments described above, a slit SL is used to fold the back surface of the first region 301 and the front surface of the second region 302 so as to overlap each other. Not exclusively. For example, the front surface of the first region 301 and the front surface of the second region 302, the back surface of the first region 301 and the back surface of the second region 302, or the front surface of the first region 301 and the back surface of the second region 302 may be overlapped together. I do not care. In this case, at least one shield may be attached to the FFC 108 so as to be located between them.

Further, in the first to fifth embodiments, the image reading unit 5 as an electronic device provided with the FFC 108 has been described, but the present invention is not limited to this. That is, the FFC 108 according to the present embodiment may be provided in, for example, a printer as an image forming apparatus, a finisher as a sheet processing apparatus, or the like, and may be provided in any electronic device.

Further, in the FFC 108 according to the first to fifth embodiments, the one having 48 conductor wires (48 cores) has been described, but the present invention is not limited to this. That is, five conductor wires (5 cores) are a conductor wire that conducts the currents of the two voltages shown in FIG. 3, a conductor wire that conducts the signal of the image data, a conductor wire that conducts the signal of serial communication, and a ground conductor wire that is grounded. ) Any number of conductors may be used as long as they have at least the above conductor wires.

Further, in the FFC 108 according to the first to fifth embodiments, the folding method shown in FIGS. 4 (c) and 5 (c) has been described, but at least the first region 301 and the second region 302 are described. Any folding method may be used as long as the folding methods partially overlap.

Further, in the first to fifth embodiments, the description has been made using the electrophotographic printer 1 (image forming apparatus), but the present invention is not limited to this. For example, it may be an inkjet type image forming apparatus that forms an image on a sheet by ejecting an ink liquid from a nozzle.

5 ... Electronic device (image reading unit) / 70 ... Sheet support unit (document base glass) / 105 ... First electronic device, reading unit (reading unit) / 108 ... Flat cable / 108a ... First terminal unit / 108b ... 2nd terminal unit / 200 ... 2nd electronic device, control unit (controller) / 204 ... light source (LED) / 207 ... imaging unit (image sensor) / 211 ... power supply unit / 301 ... 1st area / 302 ... 2 regions / CL ... Conductor wire / CL1 ... First conductor wire / CL2 ... Second conductor wire / CT1 ... First conductive part (conductive tape) / CT2 ... Second conductive part (conductive tape) / SD1, SD3 ... 1st shield member (shield) / SD2 ... 2nd shield member (shield) / SL ... Slit

Claims (11)

In a flat cable having a first terminal portion, a second terminal portion, and a plurality of conductor wires including a first conductor wire and a second conductor wire conducting the first terminal portion and the second terminal portion thereof.
The first region including the first conductor wire and
The second region including the second conductor wire and
A slit provided between the first region and the second region,
It has a first shield member that is attached to one surface of the second region and reduces the flow of an electromagnetic field.
A flat cable that features that. The first shield member is arranged so as to be located outside in the longitudinal direction from both ends of the slit.
The flat cable according to claim 1. The first shield member is made of a conductive member.
It is attached at a position connecting the first terminal portion and the first shield member on at least one surface of the second region, and conducts the ground terminal of the first terminal portion and the first shield member. Has a first conductive part,
The flat cable according to claim 2. The first shield member is bent and attached to the other surface of the second region.
It is attached at a position connecting the second terminal portion and the first shield member on at least the other surface of the second region, and conducts the ground terminal of the second terminal portion and the first shield member. Has a second conductive part,
The flat cable according to claim 3. It has a second shield member that is affixed to the other surface of the first region and reduces the flow of electromagnetic fields.
The flat cable according to any one of claims 1 to 3, wherein the flat cable is characterized in that. The second shield member is arranged so as to be located outside in the longitudinal direction from both ends of the slit.
The flat cable according to claim 5. The second shield member is made of a conductive member.
It is attached at a position connecting the second terminal portion and the second shield member on at least the other surface of the first region, and conducts the ground terminal of the second terminal portion and the second shield member. Has a second conductive part,
The flat cable according to claim 6. It has a second shield member that is attached to the other surface of the first region and reduces the flow of the electromagnetic field.
The first shield member and the second shield member are made of a conductive member.
further,
The ground terminal of the first terminal portion and the first shield member are attached so as to be connected to the first terminal portion, the first shield member, and the second shield member so as to straddle the one surface and the other surface. A first conductive portion that conducts the shield member and the second shield member,
The ground terminal of the second terminal portion and the first shield member are attached so as to be connected to the second terminal portion, the first shield member, and the second shield member so as to straddle the one surface and the other surface. It has a second conductive portion that conducts the shield member and the second shield member.
The flat cable according to claim 1 or 2. Using the slit, the first shield member is overlapped with respect to one surface of the second region so that at least a part of the other surface of the first region faces the other surface of the first region when viewed from the thickness direction of the flat cable. Is placed between one surface of the second region and the other surface of the first region.
The flat cable according to any one of claims 1 to 8, wherein the flat cable is characterized in that. The first electronic device and the second electronic device,
A flat cable having a plurality of conductor wires including a first conductor wire and a second conductor wire and transmitting a signal between the first electronic device and the second electronic device is provided.
The flat cable
The first region including the first conductor wire and
The second region including the second conductor wire and
It has a slit provided between the first region and the second region.
Using the slit, at least a part of the first region and the second region is overlapped when viewed from the thickness direction of the flat cable.
Further, it has a shield member which is arranged between the first region and the second region which are overlapped and reduces the flow of the electromagnetic field between them.
An electronic device characterized by that. It has a seat support that transmits light and supports the seat.
The first electronic device receives a light source that irradiates a sheet supported by the sheet support portion with light through the sheet support portion and light emitted from the light source and reflected by the sheet, and converts the light into an image signal. It is a reading unit that has an imaging unit and reads an image of the sheet while moving along the sheet supported by the sheet support unit.
The second electronic device has a power supply unit that supplies power, and is a control unit that controls the light source and the imaging unit.
10. The electronic device according to claim 10.

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