Flexible flat cable and electric power supply device

Abstract

Provided is a flexible flat cable that makes it possible to secure flexibility by suppressing an increase in size in the thickness direction, and to reliably adjust characteristic impedances of a first communication conductor and a second communication conductor to predetermined values. A flexible flat cable 1 includes a first communication conductor 11 and a second communication conductor 12 that are arranged at predetermined intervals in a width direction. The flexible flat cable 1 comprises a plurality of impedance adjustment portions 13 that are formed of a conductor, and are arranged at intervals in the direction in which the first communication conductor 11 and the second communication conductor 12 extend, in a portion corresponding to between at least the first communication conductor 11 and the second communication conductor 12, at positions at predetermined intervals in the thickness direction with respect to the first communication conductor 11 and the second communication conductor 12, said impedance adjustment portions adjusting the characteristic impedance of the first communication conductor 11 and the second communication conductor 12.

Description

TECHNICAL FIELD

[0001] The present invention relates to a flexible flat cable and an electric power supply device that are capable of transmitting communication signals.BACKGROUND ART

[0002] A known flexible flat cable includes a first communication conductor and a second communication conductor that are spaced apart from each other in the width direction and transmit electrical signals for communication.

[0003] In order to stabilize communication performance, especially in high-speed communication, it is necessary for the flexible flat cable to adjust the characteristic impedances of the first and second communication conductors to a predetermined value over the entire lengths thereof.

[0004] In a conventional flexible flat cable, the characteristic impedances are adjusted to a predetermined value by forming a metal layer at one or both sides of the first and second communication conductors in the thickness direction with a predetermined spacing therebetween.

[0005] However, for adjusting the characteristic impedances of the first and second communication conductors to a high value in the flexible flat cable having a metal layer, it is necessary to provide a large spacing between the metal layer and the first and second communication conductors, which can result in an increase in size in the thickness direction and a decrease in flexibility.

[0006] Patent Document 1 discloses a flexible flat cable having a metal layer. A plurality of holes are formed in the metal layer to reduce the surface area of the metal layer, thereby mitigating the influence of the metal layer on first and second communication conductors. Thus, the characteristic impedances of the first and second communication conductors are adjusted to a predetermined value without resulting in an increase in size in the thickness direction.Citation ListPatent Documents

[0007] Patent Document 1: Japanese Unexamined Patent Application, Publication No. 2007-200747DISCLOSURE OF THE INVENTIONProblems to be Solved by the Invention

[0008] However, in the flexible flat cable having a metal layer provided with a plurality of holes, the positions of the respective holes in the metal layer are allocated unequally to the first and second communication conductors, which can introduce a difference in the characteristic impedance between the first and second communication conductors.

[0009] An object of the present invention is to provide a flexible flat cable and an electric power supply device that make it possible to reliably adjust each of the characteristic impedances of first and second communication conductors to a predetermined value, while minimizing an increase in size in the thickness direction, and thus ensuring flexibility.Means for Solving the Problems

[0010] A flexible flat cable according to the present invention includes: a first communication conductor and a second communication conductor that are spaced apart from each other by a predetermined spacing in a width direction; and a plurality of impedance adjusters that are composed of a conductive material and that adjust characteristic impedances of the first and second communication conductors, the plurality of impedance adjusters being disposed in at least a region corresponding to the spacing between the first and second communication conductors at positions spaced apart from the first and second communication conductors by a predetermined spacing in a thickness direction, and arranged at intervals in a longitudinal direction of the first and second communication conductors.

[0011] Preferably, in the flexible flat cable according to the present invention, each of the impedance adjusters extends from a position corresponding to a centerline of the spacing between the first and second communication conductors toward opposite widthwise edges by an equal distance on each side.

[0012] Preferably, in the flexible flat cable according to the present invention, opposite widthwise ends of each impedance adjuster respectively extend at least to opposite widthwise ends of the first and second communication conductors paired in the width direction.

[0013] Preferably, the flexible flat cable according to the present invention further includes a connecting part composed of a conductive material and located, in the width direction, outward of the first and second communication conductors paired in the width direction, the connecting part extending in the longitudinal direction of the first and second communication conductors and connecting the impedance adjusters to each other.

[0014] Preferably, in the flexible flat cable according to the present invention, the impedance adjusters and the connecting part are formed from a conductive layer extending in the longitudinal direction of the first and second communication conductors and having a plurality of openings arranged in the longitudinal direction of the first and second communication conductors.

[0015] Preferably, in the flexible flat cable according to the present invention, the plurality of impedance adjusters each have a strip shape with a predetermined width dimension and are arranged at predetermined intervals in the longitudinal direction of the first and second communication conductors.

[0016] Preferably, the flexible flat cable according to the present invention includes a plurality of adjuster units each including multiple ones of the plurality of impedance adjusters arranged at intervals in the longitudinal direction of the first and second communication conductors, and the plurality of adjuster units are arranged in the longitudinal direction of the first and second communication conductors.

[0017] An electric power supply device according to the present invention is an electric power supply device for transmitting at least one of electric power or an electrical signal between one member and another, the electric power supply device including the flexible flat cable described above, wherein one end of the flexible flat cable is connected to the one member, and an opposite end of the flexible flat cable is connected to the other member.

[0018] In the electric power supply device according to the present invention, the one member is movable relative to the other member.Effects of the Invention

[0019] The present invention eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters is allocated equally to both the first and second communication conductors, the present invention makes it possible to adjust each of the characteristic impedances of the first and second communication conductors to a predetermined value without introducing any difference therebetween.BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 is a plan view of a flexible flat cable according to a first embodiment of the present invention; FIG. 2 is a plan view of a main portion of the flexible flat cable according to the first embodiment of the present invention; FIG. 3 is a cross-sectional view of the flexible flat cable according to the first embodiment of the present invention; FIG. 4 is a cross-sectional view for describing a structure of the flexible flat cable according to the first embodiment of the present invention in detail; FIGs. 5A to 5D are plan views of the main portion of the flexible flat cable according to the first embodiment of the present invention for describing multiple types of impedance adjusters having different width dimensions; FIG. 6 is a plan view of a main portion of a flexible flat cable according to a second embodiment of the present invention; FIG. 7 is a plan view of a main portion of a flexible flat cable according to a third embodiment of the present invention; FIG. 8 is a plan view of a main portion of a flexible flat cable according to a fourth embodiment of the present invention; FIG. 9 is a plan view of a main portion of a flexible flat cable according to a fifth embodiment of the present invention; FIG. 10 is a plan view of a main portion of a flexible flat cable according to a sixth embodiment of the present invention; FIGs. 11A to 11C are plan views of the main portion of the flexible flat cable according to the sixth embodiment of the present invention for describing multiple types of impedance adjusters having different width dimensions; FIG. 12 is a plan view of a main portion of a flexible flat cable according to a seventh embodiment of the present invention; FIG. 13 is a plan view of a main portion of a flexible flat cable according to an eighth embodiment of the present invention; FIG. 14 is a plan view of a main portion of a flexible flat cable according to a ninth embodiment of the present invention; FIG. 15 is a plan view of a main portion of a flexible flat cable according to a tenth embodiment of the present invention; FIG. 16 is a cross-sectional view of a flexible flat cable according to an eleventh embodiment of the present invention; FIG. 17 is a cross-sectional view of a flexible flat cable according to a twelfth embodiment of the present invention; FIGs. 18A to 18C are cross-sectional views of a first communication conductor and a second communication conductor; FIG. 19 is a cross-sectional view of the flexible flat cable showing another example of the arrangement of the impedance adjusters; FIG. 20 is a cross-sectional view of the flexible flat cable showing another example of the arrangement of the impedance adjusters; FIG. 21 is a cross-sectional view of the flexible flat cable showing another example of the arrangement of the impedance adjusters; FIG. 22 is a perspective view of a main portion of an electric power supply device according to a thirteenth embodiment of the present invention; FIG. 23 is a perspective view of a main portion of an electric power supply device according to a fourteenth embodiment of the present invention; FIG. 24 is a perspective view of a steering roll connector according to a fifteenth embodiment of the present invention; FIG. 25 is a plan view illustrating an internal structure of the steering roll connector according to the fifteenth embodiment of the present invention; and FIG. 26 is a plan view of a main portion of a flexible flat cable according to a sixteenth embodiment of the present invention for illustrating a connection structure thereof. PREFERRED MODE FOR CARRYING OUT THE INVENTION<First Embodiment>

[0021] FIGs. 1 to 5D are diagrams for illustrating a first embodiment of the present invention. FIG. 1 is a plan view of a flexible flat cable. FIG. 2 is a plan view of a main portion of the flexible flat cable. FIG. 3 is a cross-sectional view of the flexible flat cable. FIG. 4 is a cross-sectional view for describing a structure of the flexible flat cable in detail. FIGs. 5A to 5D are plan views of the main portion of the flexible flat cable for describing multiple types of impedance adjusters having different width dimensions.

[0022] A flexible flat cable 1 according to the present invention is, for example, applied to a movable component of a vehicle such as a steering roll connector serving as a rotary connector provided at a connection portion between a steering column on a vehicle body side and a steering shaft on a steering wheel side, a sliding door harness provided at a connection portion between the vehicle body side and a sliding door, or a sliding seat harness provided at a connection portion between the vehicle body side and a sliding seat. Alternatively, the flexible flat cable 1 is applied to a stationary component of a vehicle such as the interior of an ECU or a connection between ECUs. Furthermore, the flexible flat cable 1 according to the present invention is not limited to being applied to a vehicle and can be applied to an apparatus requiring communication between one device and another.

[0023] The flexible flat cable 1 has, for example, a width dimension of 5 mm or more and 30 mm or less, a thickness dimension of 0.1 mm or more and 0.3 mm or less, and a longitudinal dimension of 1000 mm. The flexible flat cable 1 forms a portion of a communication circuit for transmitting electrical signals between one device and another. Note here that the communication circuit is, for example, used in signal transmission based on a communication standard such as differential signal transmission employing Low Voltage Differential Signaling (LVDS) for performing high-speed transmission using low-voltage, low-amplitude signals, Controller Area Network (CAN), Controller Area Network Flexible Data Rate (CAN FD), Controller Area Network Extra Long (CAN XL), or Ethernet. The transmission rate of communication signals transmitted through the flexible flat cable 1 is generally 100 Mbps or less, but may be higher than 100 Mbps as necessary.

[0024] As shown in FIGs. 1 to 3, the flexible flat cable 1 includes: a first communication conductor 11 and a second communication conductor 12 that are spaced apart from each other by a predetermined spacing in the width direction; a plurality of impedance adjusters 13 that adjust the characteristic impedances of the first and second communication conductors 11 and 12; and an insulating material 14 that covers the first and second communication conductors 11 and 12.

[0025] Each of the first and second communication conductors 11 and 12 is composed of a material having high electrical conductivity, such as tough pitch copper. Each of the first and second communication conductors 11 and 12 has a strip shape with a rectangular transverse cross-section.

[0026] Each of the plurality of impedance adjusters 13 is, for example, composed of a metal having electrical conductivity such as copper or another conductive material such as carbon. The plurality of impedance adjusters 13 are disposed in at least a region corresponding to the spacing between the first and second communication conductors 11 and 12 at positions spaced apart from the first and second communication conductors 11 and 12 by a predetermined spacing in the thickness direction of the flexible flat cable 1, and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0027] In the present embodiment, each of the plurality of impedance adjusters 13 has a strip shape extending in the width direction of the flexible flat cable 1. Each of the plurality of impedance adjusters 13 extends from a centerline of the spacing between the first and second communication conductors 11 and 12 toward opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side.

[0028] The impedance adjusters 13 may be, for example, formed by generating a layer of a conductive material on an outer surface of the insulating material 14 through vapor deposition, sputtering, or plating, and subsequently performing etching. Alternatively, the impedance adjusters 13 may be, for example, directly formed on the outer surface of the insulating material 14 by screen printing, inkjet printing, or plating. Furthermore, the impedance adjusters 13 may be, for example, formed by attaching a plate-like member having portions removed by punching to the outer surface of the insulating material 14. The impedance adjusters 13 are formed to have a thickness dimension of, for example, 50 µm.

[0029] As shown in FIG. 4, the insulating material 14 includes a first base film 14a, a second base film 14b, and a third base film 14c, each of which is composed of an insulating material such as PET, as well as a first adhesive 14d, a second adhesive 14e, a third adhesive 14f, and a fourth adhesive 14g, each of which is a polyester-based adhesive.

[0030] In the flexible flat cable 1, the first and second communication conductors 11 and 12 are disposed between the first base film 14a and the second base film 14b with the first adhesive 14d and the second adhesive 14e therebetween, and the impedance adjusters 13 are disposed between the second base film 14b and the third base film 14c with the third adhesive 14f and the fourth adhesive 14g therebetween.

[0031] The characteristic impedances of the first and second communication conductors 11 and 12 are each adjusted to, for example, 100 Ω. In this case, the first and second communication conductors 11 and 12 are formed to have, for example, a width dimension of 0.8 mm and a thickness dimension of 35 µm, and spaced apart from each other by a spacing of 0.60 mm in the width direction of the flexible flat cable 1. The plurality of impedance adjusters 13 are spaced apart from the first and second communication conductors 11 and 12 by a spacing of, for example, 54 µm in the thickness direction of the flexible flat cable 1. Furthermore, each of the plurality of impedance adjusters 13 has a length of, for example, 0.25 mm in the short-side direction thereof (longitudinal direction of the flexible flat cable 1), and the interval between adjacent impedance adjusters 13 in the longitudinal direction of the first and second communication conductors 11 and 12 is, for example, 2.5 mm.

[0032] Note here that no limitations are imposed except that each of the plurality of impedance adjusters 13 has a length in the long-side direction thereof (width direction of the flexible flat cable 1) that is at least equal to the spacing between the first and second communication conductors 11 and 12. As shown in FIG. 5A, the impedance adjusters 13 may have a long-side length L1 equal to the spacing between the first and second communication conductors 11 and 12. As shown in FIG. 5B, the impedance adjusters 13 may have a long-side length L2 greater than the spacing between the first and second communication conductors 11 and 12, extending to respective centerlines of the first and second communication conductors 11 and 12 in the width direction. As shown in FIG. 5C, the impedance adjusters 13 may have a long-side length L3, extending to respective widthwise outer ends of the first and second communication conductors 11 and 12 paired in the width direction. As shown in FIG. 5D, the impedance adjusters 13 may have a long-side length L4, extending outward beyond the respective widthwise outer ends of the first and second communication conductors 11 and 12 paired in the width direction.

[0033] The flexible flat cable 1 having the above-described configuration forms a communication circuit between one device and another, with one end thereof connected to the one device and an opposite end thereof connected to the other device.

[0034] The plurality of impedance adjusters 13 are spaced apart from the first and second communication conductors 11 and 12 in the thickness direction, and are arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. The plurality of impedance adjusters 13 are allocated equally to both the first and second communication conductors 11 and 12. Thus, it is possible to adjust the characteristic impedances of the first and second communication conductors 11 and 12 to, for example, 100 Ω without introducing any difference therebetween.

[0035] As described above, the flexible flat cable according to the present embodiment is a flexible flat cable 1 including: a first communication conductor 11 and a second communication conductor 12 that are spaced apart from each other by a predetermined spacing in the width direction; and a plurality of impedance adjusters 13 that are composed of a conductive material and that adjust the characteristic impedances of the first and second communication conductors 11 and 12, the plurality of impedance adjusters 13 being disposed in at least a region corresponding to the spacing between the first and second communication conductors 11 and 12 at positions spaced apart from the first and second communication conductors 11 and 12 by a predetermined spacing in the thickness direction, and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0036] This configuration eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 13 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.

[0037] Preferably, each of the impedance adjusters 13 extends from a position corresponding to a centerline of the spacing between the first and second communication conductors 11 and 12 toward opposite widthwise edges by an equal distance on each side.

[0038] This configuration allows each of the impedance adjusters 13 to be allocated evenly to both the first and second communication conductors 11 and 12, making it possible to more reliably adjust the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value.

[0039] Preferably, opposite widthwise ends of each impedance adjuster 13 respectively extend at least to opposite widthwise ends of the first and second communication conductors 11 and 12 paired in the width direction.

[0040] This configuration allows the impedance adjusters 13, which are located outward of the first and second communication conductors 11 and 12 in the thickness direction, to be disposed across the width of the first and second communication conductors 11 and 12, making it possible to more reliably adjust the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value.

[0041] Preferably, the plurality of impedance adjusters 13 each have a strip shape with a predetermined width dimension and are arranged at predetermined intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0042] This configuration makes it possible to reduce the metal material usage as compared with a configuration having a metal layer formed to cover the entire flat surface of the flexible flat cable, thereby reducing manufacturing costs.<Second Embodiment>

[0043] FIG. 6 is a diagram illustrating a second embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0044] As shown in FIG. 6, each of a plurality of impedance adjusters 15 of the flexible flat cable 1 according to the present embodiment has a strip shape and extends in a direction inclined relative to the width direction and the longitudinal direction of the flexible flat cable 1. Each of the plurality of impedance adjusters 15 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side. Each of the plurality of impedance adjusters 15 extends, for example, at an angle of 15 degrees relative to the width direction of the flexible flat cable 1.

[0045] The plurality of impedance adjusters 15 of the flexible flat cable 1 having the above-described configuration each extend in a direction inclined relative to the width direction and the longitudinal direction of the flexible flat cable 1. However, the degree of inclination of the impedance adjusters 15 relative to the width direction and the longitudinal direction of the flexible flat cable 1 has little effect on the characteristic impedances of the first and second communication conductors 11 and 12 that extend in the longitudinal direction of the flexible flat cable 1. As such, the degree of inclination of the impedance adjusters 15 can be considered negligible in the flexible flat cable 1.

[0046] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 15 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Third Embodiment>

[0047] FIG. 7 is a diagram illustrating a third embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0048] As shown in FIG. 7, each of a plurality of impedance adjusters 16 of the flexible flat cable 1 according to the present embodiment has an elliptical shape. The major axis of each of the plurality of elliptical impedance adjusters 16 is oriented in the width direction of the flexible flat cable 1, and the minor axis thereof is oriented in the longitudinal direction of the flexible flat cable 1. Each of the plurality of impedance adjusters 16 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side.

[0049] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 16 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0050] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 16 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Fourth Embodiment>

[0051] FIG. 8 is a diagram illustrating a fourth embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0052] As shown in FIG. 8, each of a plurality of impedance adjusters 17 of the flexible flat cable 1 according to the present embodiment has a strip shape provided with a plurality of holes 17a. Each of the plurality of impedance adjusters 17 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side. Note here that the plurality of holes 17a may be provided in any number and at any positions in each impedance adjuster 17, provided that the size of each hole 17a is small enough that the effect thereof on the adjustment of the characteristic impedances of the first and second communication conductors 11 and 12 is negligible. On the other hand, if the size of each hole 17a is so large that the effect thereof on the adjustment of the characteristic impedances of the first and second communication conductors 11 and 12 is not negligible, it is necessary to provide a certain number of holes 17a at certain positions in each impedance adjuster 17 so that the holes 17a are equally distributed to both the first communication conductor 11 side and the second communication conductor 12 side based on the midpoint between the first and second communication conductors 11 and 12 in the width direction of the flexible flat cable 1.

[0053] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 17 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0054] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 17 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Fifth Embodiment>

[0055] FIG. 9 is a diagram illustrating a fifth embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0056] As shown in FIG. 9, each of a plurality of impedance adjusters 18 of the flexible flat cable 1 according to the present embodiment has a strip shape and extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side. The flexible flat cable 1 further includes connecting parts 18a that integrally connect ends of the plurality of impedance adjusters 18 on each side.

[0057] The connecting parts 18a are composed of the same material as the impedance adjusters 18. The connecting parts 18a are located toward the opposite widthwise outer edges of the flexible flat cable 1 and extend in the longitudinal direction of the flexible flat cable 1. The connecting parts 18a are connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected, and equalize the potentials of the plurality of impedance adjusters 18 connected to the connecting parts 18a.

[0058] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 18 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. Furthermore, since the plurality of impedance adjusters 18 are connected to a ground via the connecting parts 18a, the flexible flat cable 1 makes it possible to stabilize the potentials of the plurality of impedance adjusters 18.

[0059] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 18 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.

[0060] Preferably, the flexible flat cable 1 further includes the connecting parts 18a composed of a conductive material and located, in the width direction, outward of the first and second communication conductors 11 and 12 paired in the width direction, and the connecting parts 18a extend in the longitudinal direction of the first and second communication conductors 11 and 12 and connect the impedance adjusters 18 to each other.

[0061] This configuration makes it possible to stabilize the potentials of the plurality of impedance adjusters 18, thereby enhancing communication performance.<Sixth Embodiment>

[0062] FIGs. 10 and 11A to 11C are diagrams illustrating a sixth embodiment of the present invention. FIG. 10 is a plan view of a main portion of a flexible flat cable. FIGs. 11A to 11C are plan views of the main portion of the flexible flat cable for describing multiple types of impedance adjusters having different width dimensions.

[0063] As shown in FIG. 10, each of a plurality of impedance adjusters 19 of the flexible flat cable 1 according to the present embodiment has a strip shape and extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side. The flexible flat cable 1 further includes connecting parts 19a that integrally connect ends of the plurality of impedance adjusters 19 on each side.

[0064] The connecting parts 19a are composed of the same material as the impedance adjusters 19, and extend in the longitudinal direction of the flexible flat cable 1 and respectively span the entire surfaces of regions from the opposite ends of the impedance adjusters 19 to the opposite widthwise outer edges of the flexible flat cable 1. The connecting parts 19a are connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected, and equalize the potentials of the plurality of impedance adjusters 19 connected to the connecting parts 19a.

[0065] Furthermore, no limitations are imposed except that each of the plurality of impedance adjusters 19 has a length in the long-side direction thereof (width direction of the flexible flat cable 1) that extends outward at least beyond the widthwise outer ends of the paired first and second communication conductors 11 and 12. The extent to which the long-side length of the impedance adjusters 19 extends outward beyond the widthwise outer ends of the paired first and second communication conductors 11 and 12 may be varied as indicated by L1, L2, and L3 in FIGs. 11A, 11B, and 11C. In this case, the characteristic impedances of the first and second communication conductors 11 and 12 increase as the long-side length of the impedance adjusters 19 increases, but the amount of increase decreases once the long-side length exceeds a certain value.

[0066] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 19 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. Furthermore, since the plurality of impedance adjusters 19 are connected to a ground via the connecting parts 19a, the flexible flat cable 1 makes it possible to stabilize the potentials of the plurality of impedance adjusters 19.

[0067] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 19 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Seventh Embodiment>

[0068] FIG. 12 is a diagram illustrating a seventh embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0069] As shown in FIG. 12, each of a plurality of impedance adjusters 20 of the flexible flat cable 1 according to the present embodiment has a strip shape. Each of the plurality of impedance adjusters 20 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1, and has one end and an opposite end in the width direction of the flexible flat cable 1. The plurality of impedance adjusters 20 include a plurality of first adjusters 20a and a plurality of second adjusters 20b. The one end of each first adjuster 20a extends farther than the opposite end thereof. The opposite end of each second adjuster 20b extends farther than the one end thereof. The first adjusters 20a and the second adjusters 20b are alternately arranged in the longitudinal direction of the flexible flat cable 1.

[0070] The flexible flat cable 1 further includes a first connecting part 20c that integrally connects the plurality of first adjusters 20a and a second connecting part 20d that integrally connects the plurality of second adjusters 20b.

[0071] The first connecting part 20c is composed of the same material as the first adjusters 20a. The first connecting part 20c is located toward one widthwise edge of the flexible flat cable 1 and extends in the longitudinal direction of the flexible flat cable 1. The first connecting part 20c is connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected and equalizes the potentials of the plurality of first adjusters 20a.

[0072] The second connecting part 20d is composed of the same material as the second adjusters 20b. The second connecting part 20d is located toward an opposite widthwise edge of the flexible flat cable 1 and extends in the longitudinal direction of the flexible flat cable 1. The second connecting part 20d is connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected and equalizes the potentials of the plurality of second adjusters 20b.

[0073] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 20 (first and second adjusters 20a and 20b) spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. Furthermore, since the plurality of impedance adjusters 20 (first and second adjusters 20a and 20b) are connected to a ground via the first and second connecting parts 20c and 20d, the flexible flat cable 1 makes it possible to stabilize the potentials of the plurality of impedance adjusters 20.

[0074] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 20 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Eighth Embodiment>

[0075] FIG. 13 is a diagram illustrating an eighth embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0076] As shown in FIG. 13, each of a plurality of impedance adjusters 21 of the flexible flat cable 1 according to the present embodiment has a strip shape. Each of the plurality of impedance adjusters 21 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1, and has one end and an opposite end in the width direction of the flexible flat cable 1. The plurality of impedance adjusters 21 include a plurality of first adjusters 21a, a plurality of second adjusters 21b, and a third adjuster 21c. The one end of each first adjuster 21a extends farther than the opposite end thereof. The opposite end of each second adjuster 21b extends farther than the one end thereof. The third adjuster 21c extends toward the opposite widthwise edges of the flexible flat cable 1 by an equal length on each side. The first adjusters 21a and the second adjusters 21b are alternately arranged in the longitudinal direction of the flexible flat cable 1. The first adjusters 21a and the second adjusters 21b alternately arranged in the longitudinal direction of the flexible flat cable 1 have at least one third adjuster 21c therebetween.

[0077] The flexible flat cable 1 further includes a first connecting part 21d that integrally connects the plurality of first adjusters 21a and a second connecting part 21e that integrally connects the plurality of second adjusters 21b.

[0078] The first connecting part 21d is composed of the same material as the first adjusters 21a. The first connecting part 21d is located toward one widthwise edge of the flexible flat cable 1 and extends in the longitudinal direction of the flexible flat cable 1.

[0079] The second connecting part 21e is composed of the same material as the second adjusters 21b. The second connecting part 21e is located toward an opposite widthwise edge of the flexible flat cable 1 and extends in the longitudinal direction of the flexible flat cable 1.

[0080] The third adjuster 21c connects the first connecting part 21d and the second connecting part 21e to each other. At least one of the first connecting part 21d or the second connecting part 21e is connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected and equalizes the potentials of the plurality of impedance adjusters 21 (first, second, and third adjusters 21a, 21b, and 21c).

[0081] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 21 (first, second, and third adjusters 21a, 21b, and 21c) spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. Furthermore, since the plurality of impedance adjusters 21 (first, second, and third adjusters 21a, 21b, and 21c) are connected to a ground via the first and second connecting parts 21d and 21e, the flexible flat cable 1 makes it possible to stabilize the potentials of the plurality of impedance adjusters 21 (first, second, and third adjusters 21a, 21b, and 21c).

[0082] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 21 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Ninth Embodiment>

[0083] FIG. 14 is a diagram illustrating a ninth embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0084] As shown in FIG. 14, a plurality of impedance adjusters 22 and a connecting part 22a of the flexible flat cable 1 according to the present embodiment are spaced apart from the first and second communication conductors 11 and 12 in the thickness direction, and are formed from a metal layer 23, which serves as a conductive layer, extending in the longitudinal direction of the first and second communication conductors 11 and 12, and having a plurality of openings 23a arranged in the longitudinal direction of the first and second communication conductors 11 and 12.

[0085] The plurality of impedance adjusters 22 are formed between adjacent openings 23a in the metal layer 23. As in the case of the first embodiment, each of the plurality of impedance adjusters 22 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1.

[0086] The metal layer 23 is connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected, and thus the potentials of the plurality of impedance adjusters 21 are equalized.

[0087] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 22 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. Furthermore, since the plurality of impedance adjusters 22 are connected to a ground via the connecting part 22a, the flexible flat cable 1 makes it possible to stabilize the potentials of the plurality of impedance adjusters 22.

[0088] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 22 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.

[0089] Furthermore, preferably, the impedance adjusters 22 and the connecting part 22a are formed from the metal layer 23, which serves as a conductive layer, extending in the longitudinal direction of the first and second communication conductors 11 and 12, and having the plurality of openings 23a arranged in the longitudinal direction of the first and second communication conductors 11 and 12.

[0090] This configuration makes it possible to form the impedance adjusters 22 and the connecting part 22a using a simple configuration of a single metal layer 23, thereby reducing manufacturing costs.<Tenth Embodiment>

[0091] FIG. 15 is a diagram illustrating a tenth embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0092] As shown in FIG. 15, the flexible flat cable 1 according to the present embodiment includes a plurality of adjuster units 24 each including multiple types of impedance adjusters 24a, 24b, 24c, 24d, and 24e that are different in length in the short-side direction thereof (longitudinal direction of the flexible flat cable 1) and that are arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0093] The plurality of adjuster units 24 are arranged in the longitudinal direction of the first and second communication conductors 11 and 12. The plurality of adjuster units 24 are integrated by connecting opposite ends of the multiple types of impedance adjusters 24a, 24b, 24c, 24d, and 24e on each side using connecting parts 24f.

[0094] The connecting parts 24f are composed of the same material as the impedance adjusters 24a, 24b, 24c, 24d, and 24e. The connecting parts 24f extend in the longitudinal direction of the flexible flat cable 1 and respectively span the entire surfaces of regions from the opposite ends of the impedance adjusters 24a, 24b, 24c, 24d, and 24e to the opposite widthwise outer edges of the flexible flat cable 1. The connecting parts 24f are connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected, and equalize the potentials of the impedance adjusters 24a, 24b, 24c, 24d, and 24e connected to the connecting parts 24f.

[0095] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of adjuster units 24 each including the multiple types of impedance adjusters 24a, 24b, 24c, 24d, and 24e spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. Furthermore, since the multiple types of impedance adjusters 24a, 24b, 24c, 24d, and 24e are connected to a ground via the connecting parts 24f, the flexible flat cable 1 makes it possible to stabilize the potentials of the multiple types of impedance adjusters 24a, 24b, 24c, 24d, and 24e in the plurality of adjuster units 24.

[0096] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 24a, 24b, 24c, 24d, and 24e is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.

[0097] The flexible flat cable according to the present embodiment includes the plurality of adjuster units 24 each including the multiple impedance adjusters 24a, 24b, 24c, 24d, and 24e arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12, and the plurality of adjuster units 24 are arranged in the longitudinal direction of the first and second communication conductors 11 and 12.

[0098] This configuration allows each adjuster unit 24 including the multiple impedance adjusters 24a, 24b, 24c, 24d, and 24e to be handled as a single component, making it possible to reduce the amount of labor required for assembly.<Eleventh Embodiment>

[0099] FIG. 16 is a diagram illustrating an eleventh embodiment of the present invention and is a cross-sectional view of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0100] As shown in FIG. 16, the flexible flat cable 1 according to the present embodiment includes additional conductors 25 located, with a spacing in the width direction, outward of the first and second communication conductors 11 and 12 paired in the width direction. The conductors 25 are, for example, used for transmitting electric power between one device and another.

[0101] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 13 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0102] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 13 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Twelfth Embodiment>

[0103] FIG. 17 is a diagram illustrating a twelfth embodiment of the present invention and is a cross-sectional view of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0104] As shown in FIG. 17, the flexible flat cable 1 according to the present embodiment includes a pair of ground conductors 26 located, with a spacing in the width direction, outward of the first and second communication conductors 11 and 12 paired in the width direction.

[0105] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 13 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. The characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by changing the spacing between the ground conductors 26 and the first and second communication conductors 11 and 12.

[0106] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 13 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.

[0107] It should be noted that the cross-sectional shapes of the first and second communication conductors 11 and 12 are rectangular in the foregoing embodiments, but are not limited as such. As the cross-sectional shapes, the first and second communication conductors may have a rectangular transverse cross-sectional shape as shown in FIG. 18A or a circular transverse cross-sectional shape as shown in FIG. 18B. Alternatively, the first and second communication conductors may each be a twisted wire formed by twisting thin conductive strands as shown in FIG. 18C. Moreover, the first communication conductor 11 and the second communication conductor may have different transverse cross-sectional shapes, as long as the first and second communication conductors have substantially the same conductor resistance.

[0108] In the first embodiment, as shown in FIG. 3, the impedance adjusters 13 are disposed on the outer surface of the insulating material 14 that covers the first and second communication conductors 11 and 12. However, the impedance adjusters 13 are not limited as such. The impedance adjusters 13 may be embedded within the insulating material 14 as shown in FIG. 19, as long as the impedance adjusters 13 are disposed at positions spaced apart from the first and second communication conductors 11 and 12 by a predetermined spacing in the thickness direction of the flexible flat cable 1. Alternatively, the impedance adjusters 13 may be embedded in the insulating material 14 so that outer surfaces thereof are flush with the outer surface of the insulating material 14 as shown in FIG. 20. Alternatively, a portion of each of the impedance adjusters 13 including the outer surface thereof may project from the insulating material 14, and the remaining portion may be embedded within the insulating material 14 as shown in FIG. 21.

[0109] The flexible flat cables 1 described in the foregoing embodiments are applicable to electric power supply devices described in detail in thirteenth to fifteenth embodiments below. Each electric power supply device transmits at least one of electric power or electrical signals between one member and another, and includes a flexible flat cable. One end of the flexible flat cable is connected to the one member, and an opposite end of the flexible flat cable is connected to the other member.<Thirteenth Embodiment>

[0110] FIG. 22 is a diagram illustrating the thirteenth embodiment of the present invention and is a perspective view of a main portion of an electric power supply device. It should be noted that the same elements of configuration as in the first to twelfth embodiments are labeled with the same reference numerals as in the first to twelfth embodiments.

[0111] With respect to the present embodiment, the following describes, as an example of an application for the flexible flat cable 1, an electric power supply device 100 for a sliding door that transmits at least one of electric power or electrical signals between a vehicle body B as one member of a vehicle and a sliding door D as another member.

[0112] The electric power supply device 100 includes a flexible flat cable 1.

[0113] A connector 2 is connected to each of the opposite ends of the flexible flat cable 1.

[0114] One end of the flexible flat cable 1 is connected to the vehicle body B via the connector 2.

[0115] The opposite end of the flexible flat cable 1 is connected to the sliding door D via the connector 2.

[0116] That is, the flexible flat cable 1 connects an electrical circuit provided on the vehicle body B side with an electrical circuit provided on the sliding door D side.

[0117] The flexible flat cable 1 installed between the vehicle body B and the sliding door D extends in one direction along the moving direction of the sliding door D, is curved into a U-shape to reverse direction, and extends in an opposite direction along the moving direction of the sliding door D. In this embodiment, a portion of the flexible flat cable 1 curved into a U-shape to reverse direction is defined as a reversal portion 1a.

[0118] In the electric power supply device 100 having the above-described configuration, when the sliding door D is opened or closed, only the position of the reversal portion 1a in the lengthwise direction changes, while the directions in which the flexible flat cable 1 extends are maintained.

[0119] As such, the flexible flat cable 1 transmits at least one of electric power or electrical signals between the vehicle body B and the sliding door D without interfering with the movement of the sliding door D relative to the vehicle body B.

[0120] As described above, the electric power supply device according to the present embodiment is an electric power supply device 100 for transmitting at least one of electric power or electrical signals between a vehicle body B and a sliding door D. The electric power supply device 100 includes a flexible flat cable 1. One end of the flexible flat cable 1 is connected to the vehicle body B, and an opposite end of the flexible flat cable 1 is connected to the sliding door D.

[0121] This configuration makes it possible to enhance communication performance in high-speed communication between the vehicle body B and the sliding door D since the flexible flat cable 1, which includes the first and second communication conductors 11 and 12 with adjusted characteristic impedances, is used to transmit at least one of electric power or electrical signals between the vehicle body B and the sliding door D.

[0122] The sliding door D is movable relative to the vehicle body B.

[0123] Using the flexible flat cable 1 as wiring to connect the vehicle body B and the sliding door D makes it possible to transmit at least one of electric power or electrical signals without interfering with the movement of the sliding door D relative to the vehicle body B.<Fourteenth Embodiment>

[0124] FIG. 23 is a diagram illustrating the fourteenth embodiment of the present invention and is a perspective view of a main portion of an electric power supply device. It should be noted that the same elements of configuration as in the first to thirteenth embodiments are labeled with the same reference numerals as in the first to thirteenth embodiments.

[0125] With respect to the present embodiment, the following describes, as an example of an application for the flexible flat cable 1, an electric power supply device 200 for a sliding seat that transmits at least one of electric power or electrical signals between a vehicle body B as one member of a vehicle and a sliding seat S as another member.

[0126] The electric power supply device 200 includes a flexible flat cable 1.

[0127] A connector 2 is connected to each of the opposite ends of the flexible flat cable 1.

[0128] The vehicle body B has a connector BC that forms an electrical circuit on the vehicle body B side. One end of the flexible flat cable 1 is connected to the connector BC via the connector 2.

[0129] The sliding seat S has a connector SC that forms an electrical circuit on the sliding seat S side. The opposite end of the flexible flat cable 1 is connected to the connector SC via the connector 2.

[0130] That is, the flexible flat cable 1 connects the electrical circuit provided on the vehicle body B side with the electrical circuit provided on the sliding seat S side.

[0131] The flexible flat cable 1 installed between the vehicle body B and the sliding seat S extends upward from the vehicle body B, bends in the horizontal direction, extends in one direction along the moving direction of the sliding seat S, reverses direction through a reversal portion 1a, and extends in an opposite direction along the moving direction of the sliding seat S.

[0132] In the electric power supply device 200 having the above-described configuration, when the sliding seat S moves in the front-rear direction, only the position of the reversal portion 1a in the lengthwise direction changes, while the orientation in which the flexible flat cable 1 extends along the moving direction of the sliding seat S is maintained.

[0133] As such, the flexible flat cable 1 transmits at least one of electric power or electrical signals between the vehicle body B and the sliding seat S without interfering with the movement of the sliding seat S relative to the vehicle body B.

[0134] As described above, the electric power supply device according to the present embodiment is an electric power supply device 200 for transmitting at least one of electric power or electrical signals between a vehicle body B and a sliding seat S. The electric power supply device 200 includes a flexible flat cable 1. One end of the flexible flat cable 1 is connected to the vehicle body B, and an opposite end of the flexible flat cable 1 is connected to the sliding seat S.

[0135] This configuration makes it possible to enhance communication performance in high-speed communication between the vehicle body B and the sliding seat S since the flexible flat cable 1, which includes the first and second communication conductors 11 and 12 with adjusted characteristic impedances, is used to transmit at least one of electric power or electrical signals between the vehicle body B and the sliding seat S.

[0136] The sliding seat S is movable relative to the vehicle body B.

[0137] Using the flexible flat cable 1 as wiring to connect the vehicle body B and the sliding seat S makes it possible to transmit at least one of electric power or electrical signals without interfering with the movement of the sliding seat S relative to the vehicle body B.<Fifteenth Embodiment>

[0138] FIGs. 24 and 25 are diagrams illustrating the fifteenth embodiment of the present invention. FIG. 24 is a perspective view of a steering roll connector, and FIG. 25 is a plan view illustrating an internal structure of the steering roll connector. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0139] With respect to the present embodiment, the following describes, as an example of an application for the flexible flat cable 1, a steering roll connector 300 that is used as an electric power supply device to be provided at a connection portion between a steering column on a vehicle body side and a steering shaft on a steering wheel side in a vehicle.

[0140] The steering roll connector 300 transmits at least one of electric power or electrical signals between a device provided on the steering wheel connected to the steering shaft rotatable relative to the vehicle body and a device provided on the vehicle body.

[0141] As shown in FIGs. 24 and 25, the steering roll connector 300 includes a plurality of flexible flat cables 1, a fixed-side housing 310 as one member, which is fixed to the steering column, and a rotating-side housing 320 as another member, which is fixed to the steering shaft.

[0142] The fixed-side housing 310 includes a fixed-side ring part 311 having an opening through which the steering shaft can be inserted, and a cylindrical outer peripheral part 312 having a hollow cylindrical shape extending vertically from the outer periphery of the fixed-side ring part 311. The outer periphery of the cylindrical outer peripheral part 312 is provided with a first fixed-side connector 313 to which one end of at least one of the plurality of flexible flat cables 1 is connected, and a second fixed-side connector 314 to which one end of each of the remaining flexible flat cables 1 is connected.

[0143] The rotating-side housing 320 includes a rotating-side ring part 321 disposed to face the fixed-side ring part 311 and provided with an opening through which the steering shaft can be inserted, and a cylindrical inner peripheral part 322 disposed to face the cylindrical outer peripheral part 312 and having a hollow cylindrical shape extending vertically from the inner periphery of the rotating-side ring part 321. The outer surface of the rotating-side ring part 321 is provided with a first rotating-side connector 323 to which an opposite end of the at least one of the plurality of flexible flat cables 1 having the one end connected to the first fixed-side connector 313 is connected, and a second rotating-side connector 324 to which an opposite end of each of the remaining flexible flat cables 1 having the one end connected to the second fixed-side connector 314 is connected.

[0144] As shown in FIG. 25, an accommodating space S that accommodates the plurality of flexible flat cables 1 is formed between the fixed-side housing 310 and the rotating-side housing 320. The accommodating space S has an annular shape defined by the fixed-side ring part 311 and the cylindrical outer peripheral part 312 of the fixed-side housing 310, and the rotating-side ring part 321 and the cylindrical inner peripheral part 322 of the rotating-side housing 320.

[0145] The plurality of flexible flat cables 1, which are arranged in layers and separable from each other, are accommodated in the accommodating space S. Each of the plurality of flexible flat cables 1 is fixed to the cylindrical outer peripheral part 312 at the one end thereof, wound along the inner surface of the cylindrical outer peripheral part 312 in one direction along the rotation direction of the rotating-side housing 320, curved into a U-shape at a middle portion thereof to reverse direction between the cylindrical outer peripheral part 312 and the cylindrical inner peripheral part 322, wound in an opposite direction along the rotation direction, and fixed to the cylindrical inner peripheral part 322 at the opposite end thereof.

[0146] As shown in FIG. 25, the middle portion of each of the plurality of flexible flat cables 1 accommodated in the accommodating space S has a reversal portion 1a that moves as the rotating-side housing 320 rotates relative to the fixed-side housing 310. When each of the reversal portions 1a is located at the center of the corresponding flexible flat cable 1 in the longitudinal direction, the rotating-side housing 320 is allowed to rotate relative to the fixed-side housing 310 by the same angle in the one direction and in the opposite direction.

[0147] In the steering roll connector 300 having the above-described configuration, the rotating-side housing 320 rotates relative to the fixed-side housing 310 as the steering shaft rotates.

[0148] During the rotation, the reversal portions 1a of the flexible flat cables 1 maintain the direction-reversing state and move within the annular accommodating space S. As such, the flexible flat cables 1 transmit at least one of electric power or electrical signals between the vehicle body side, to which the fixed-side housing 310 is fixed, and the steering shaft side, to which the rotating-side housing 320 is fixed, without interfering with the rotation of the rotating-side housing 320 relative to the fixed-side housing 310.

[0149] As described above, the electric power supply device according to the present embodiment is a steering roll connector 300 for transmitting at least one of electric power or electrical signals between a fixed-side housing 310 and a rotating-side housing 320. The steering roll connector 300 includes a plurality of flexible flat cables 1. One end of each flexible flat cable 1 is connected to the fixed-side housing 310, and an opposite end of each flexible flat cable 1 is connected to the rotating-side housing 320.

[0150] This configuration makes it possible to enhance communication performance in high-speed communication between the vehicle body and the steering wheel since the flexible flat cables 1, which each include the first and second communication conductors 11 and 12 with adjusted characteristic impedances, are used to transmit at least one of electric power or electrical signals between the fixed-side housing 310 and the rotating-side housing 320.

[0151] Furthermore, the rotating-side housing 320 is rotatable relative to the fixed-side housing 310.

[0152] Using the flexible flat cables 1 as wiring to connect the fixed-side housing 310 and the rotating-side housing 320 makes it possible to transmit at least one of electric power or electrical signals without interfering with the rotational movement of the rotating-side housing 320 relative to the fixed-side housing 310.<Sixteenth Embodiment>

[0153] FIG. 26 is a diagram illustrating the sixteenth embodiment of the present invention and is a plan view of a main portion of a flexible flat cable for illustrating a connection structure thereof. It should be noted that the same elements of configuration as in the first to fifteenth embodiments are labeled with the same reference numerals as in the first to fifteenth embodiments.

[0154] The flexible flat cable 1 including a connection structure according to the present embodiment is connected to a conductive circuit and a communication circuit via a connector 400. As shown in FIG. 26, each of the first and second communication conductors 11 and 12 of the flexible flat cable 1 is connected to a bus bar 410, which is a connection target forming the connector 400. The bus bars 410 are, for example, members having electrical conductivity such as brass.

[0155] In the present embodiment, the connection structure is applied to the connection between the first and second communication conductors 11 and 12 and the respective bus bars 410.

[0156] The connection structure includes connection portions 420, which are portions of the first and second communication conductors 11 and 12 of the flexible flat cable 1 that are connected to the bus bars 410. The connection portions 420 are located at respective ends of the first and second communication conductors 11 and 12.

[0157] The connection portions 420 are formed by joining the first and second communication conductors 11 and 12 to the bus bars 410 by ultrasonic welding, resistance welding, or soldering. The flexible flat cable 1 including the connection structure according to the present embodiment can be, for example, used by being incorporated in any of the electric power supply devices according to the thirteenth to fifteenth embodiments of the present invention described above.EXPLANATION OF REFERENCE NUMERALS

[0158] 1: Flexible flat cable 11: First communication conductor 12: Second communication conductor 13, 15, 16, 17, 18: Impedance adjuster 18a, 19a: Connecting part 20: Impedance adjuster 20a: First adjuster 20b: Second adjuster 20c: First connecting part 20d: Second connecting part 21: Impedance adjuster 21a: First adjuster 21b: Second adjuster 21d: First connecting part 21e: Second connecting part 22: Impedance adjuster 23: Metal layer 23a: Opening 24: Adjuster unit 24a, 24b, 24c, 24d, 24e: Impedance adjuster 100, 200: Electric power supply device 300: Steering roll connector 310: Fixed-side housing 320: Rotating-side housing B: Vehicle body D: Sliding door S: Sliding seat

Examples

first embodiment

[0021]FIGs. 1 to 5D are diagrams for illustrating the present invention. FIG. 1 is a plan view of a flexible flat cable. FIG. 2 is a plan view of a main portion of the flexible flat cable. FIG. 3 is a cross-sectional view of the flexible flat cable. FIG. 4 is a cross-sectional view for describing a structure of the flexible flat cable in detail. FIGs. 5A to 5D are plan views of the main portion of the flexible flat cable for describing multiple types of impedance adjusters having different width dimensions.

[0022]A flexible flat cable 1 according to the present invention is, for example, applied to a movable component of a vehicle such as a steering roll connector serving as a rotary connector provided at a connection portion between a steering column on a vehicle body side and a steering shaft on a steering wheel side, a sliding door harness provided at a connection portion between the vehicle body side and a sliding door, or a sliding seat harness provided at a connection portion b...

sixth embodiment

[0062]FIGs. 10 and 11A to 11C are diagrams illustrating the present invention. FIG. 10 is a plan view of a main portion of a flexible flat cable. FIGs. 11A to 11C are plan views of the main portion of the flexible flat cable for describing multiple types of impedance adjusters having different width dimensions.

[0063]As shown in FIG. 10, each of a plurality of impedance adjusters 19 of the flexible flat cable 1 according to the present embodiment has a strip shape and extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side. The flexible flat cable 1 further includes connecting parts 19a that integrally connect ends of the plurality of impedance adjusters 19 on each side.

[0064]The connecting parts 19a are composed of the same material as the impedance adjusters 19, and extend in the longitudinal direction of the flexible flat cable 1...

eighth embodiment

[0075]FIG. 13 is a diagram illustrating the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0076]As shown in FIG. 13, each of a plurality of impedance adjusters 21 of the flexible flat cable 1 according to the present embodiment has a strip shape. Each of the plurality of impedance adjusters 21 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1, and has one end and an opposite end in the width direction of the flexible flat cable 1. The plurality of impedance adjusters 21 include a plurality of first adjusters 21a, a plurality of second adjusters 21b, and a third adjuster 21c. The one end of each first adjuster 21a extends farther than the opposite end thereof. The oppo...

TECHNICAL FIELD

[0001] The present invention relates to a flexible flat cable and an electric power supply device that are capable of transmitting communication signals.BACKGROUND ART

[0002] A known flexible flat cable includes a first communication conductor and a second communication conductor that are spaced apart from each other in the width direction and transmit electrical signals for communication.

[0003] In order to stabilize communication performance, especially in high-speed communication, it is necessary for the flexible flat cable to adjust the characteristic impedances of the first and second communication conductors to a predetermined value over the entire lengths thereof.

[0004] In a conventional flexible flat cable, the characteristic impedances are adjusted to a predetermined value by forming a metal layer at one or both sides of the first and second communication conductors in the thickness direction with a predetermined spacing therebetween.

[0005] However, for adjusting the characteristic impedances of the first and second communication conductors to a high value in the flexible flat cable having a metal layer, it is necessary to provide a large spacing between the metal layer and the first and second communication conductors, which can result in an increase in size in the thickness direction and a decrease in flexibility.

[0006] Patent Document 1 discloses a flexible flat cable having a metal layer. A plurality of holes are formed in the metal layer to reduce the surface area of the metal layer, thereby mitigating the influence of the metal layer on first and second communication conductors. Thus, the characteristic impedances of the first and second communication conductors are adjusted to a predetermined value without resulting in an increase in size in the thickness direction.Citation ListPatent Documents

[0007] Patent Document 1: Japanese Unexamined Patent Application, Publication No. 2007-200747DISCLOSURE OF THE INVENTIONProblems to be Solved by the Invention

[0008] However, in the flexible flat cable having a metal layer provided with a plurality of holes, the positions of the respective holes in the metal layer are allocated unequally to the first and second communication conductors, which can introduce a difference in the characteristic impedance between the first and second communication conductors.

[0009] An object of the present invention is to provide a flexible flat cable and an electric power supply device that make it possible to reliably adjust each of the characteristic impedances of first and second communication conductors to a predetermined value, while minimizing an increase in size in the thickness direction, and thus ensuring flexibility.Means for Solving the Problems

[0010] A flexible flat cable according to the present invention includes: a first communication conductor and a second communication conductor that are spaced apart from each other by a predetermined spacing in a width direction; and a plurality of impedance adjusters that are composed of a conductive material and that adjust characteristic impedances of the first and second communication conductors, the plurality of impedance adjusters being disposed in at least a region corresponding to the spacing between the first and second communication conductors at positions spaced apart from the first and second communication conductors by a predetermined spacing in a thickness direction, and arranged at intervals in a longitudinal direction of the first and second communication conductors.

[0011] Preferably, in the flexible flat cable according to the present invention, each of the impedance adjusters extends from a position corresponding to a centerline of the spacing between the first and second communication conductors toward opposite widthwise edges by an equal distance on each side.

[0012] Preferably, in the flexible flat cable according to the present invention, opposite widthwise ends of each impedance adjuster respectively extend at least to opposite widthwise ends of the first and second communication conductors paired in the width direction.

[0013] Preferably, the flexible flat cable according to the present invention further includes a connecting part composed of a conductive material and located, in the width direction, outward of the first and second communication conductors paired in the width direction, the connecting part extending in the longitudinal direction of the first and second communication conductors and connecting the impedance adjusters to each other.

[0014] Preferably, in the flexible flat cable according to the present invention, the impedance adjusters and the connecting part are formed from a conductive layer extending in the longitudinal direction of the first and second communication conductors and having a plurality of openings arranged in the longitudinal direction of the first and second communication conductors.

[0015] Preferably, in the flexible flat cable according to the present invention, the plurality of impedance adjusters each have a strip shape with a predetermined width dimension and are arranged at predetermined intervals in the longitudinal direction of the first and second communication conductors.

[0016] Preferably, the flexible flat cable according to the present invention includes a plurality of adjuster units each including multiple ones of the plurality of impedance adjusters arranged at intervals in the longitudinal direction of the first and second communication conductors, and the plurality of adjuster units are arranged in the longitudinal direction of the first and second communication conductors.

[0017] An electric power supply device according to the present invention is an electric power supply device for transmitting at least one of electric power or an electrical signal between one member and another, the electric power supply device including the flexible flat cable described above, wherein one end of the flexible flat cable is connected to the one member, and an opposite end of the flexible flat cable is connected to the other member.

[0018] In the electric power supply device according to the present invention, the one member is movable relative to the other member.Effects of the Invention

[0019] The present invention eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters is allocated equally to both the first and second communication conductors, the present invention makes it possible to adjust each of the characteristic impedances of the first and second communication conductors to a predetermined value without introducing any difference therebetween.BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 is a plan view of a flexible flat cable according to a first embodiment of the present invention; FIG. 2 is a plan view of a main portion of the flexible flat cable according to the first embodiment of the present invention; FIG. 3 is a cross-sectional view of the flexible flat cable according to the first embodiment of the present invention; FIG. 4 is a cross-sectional view for describing a structure of the flexible flat cable according to the first embodiment of the present invention in detail; FIGs. 5A to 5D are plan views of the main portion of the flexible flat cable according to the first embodiment of the present invention for describing multiple types of impedance adjusters having different width dimensions; FIG. 6 is a plan view of a main portion of a flexible flat cable according to a second embodiment of the present invention; FIG. 7 is a plan view of a main portion of a flexible flat cable according to a third embodiment of the present invention; FIG. 8 is a plan view of a main portion of a flexible flat cable according to a fourth embodiment of the present invention; FIG. 9 is a plan view of a main portion of a flexible flat cable according to a fifth embodiment of the present invention; FIG. 10 is a plan view of a main portion of a flexible flat cable according to a sixth embodiment of the present invention; FIGs. 11A to 11C are plan views of the main portion of the flexible flat cable according to the sixth embodiment of the present invention for describing multiple types of impedance adjusters having different width dimensions; FIG. 12 is a plan view of a main portion of a flexible flat cable according to a seventh embodiment of the present invention; FIG. 13 is a plan view of a main portion of a flexible flat cable according to an eighth embodiment of the present invention; FIG. 14 is a plan view of a main portion of a flexible flat cable according to a ninth embodiment of the present invention; FIG. 15 is a plan view of a main portion of a flexible flat cable according to a tenth embodiment of the present invention; FIG. 16 is a cross-sectional view of a flexible flat cable according to an eleventh embodiment of the present invention; FIG. 17 is a cross-sectional view of a flexible flat cable according to a twelfth embodiment of the present invention; FIGs. 18A to 18C are cross-sectional views of a first communication conductor and a second communication conductor; FIG. 19 is a cross-sectional view of the flexible flat cable showing another example of the arrangement of the impedance adjusters; FIG. 20 is a cross-sectional view of the flexible flat cable showing another example of the arrangement of the impedance adjusters; FIG. 21 is a cross-sectional view of the flexible flat cable showing another example of the arrangement of the impedance adjusters; FIG. 22 is a perspective view of a main portion of an electric power supply device according to a thirteenth embodiment of the present invention; FIG. 23 is a perspective view of a main portion of an electric power supply device according to a fourteenth embodiment of the present invention; FIG. 24 is a perspective view of a steering roll connector according to a fifteenth embodiment of the present invention; FIG. 25 is a plan view illustrating an internal structure of the steering roll connector according to the fifteenth embodiment of the present invention; and FIG. 26 is a plan view of a main portion of a flexible flat cable according to a sixteenth embodiment of the present invention for illustrating a connection structure thereof. PREFERRED MODE FOR CARRYING OUT THE INVENTION<First Embodiment>

[0021] FIGs. 1 to 5D are diagrams for illustrating a first embodiment of the present invention. FIG. 1 is a plan view of a flexible flat cable. FIG. 2 is a plan view of a main portion of the flexible flat cable. FIG. 3 is a cross-sectional view of the flexible flat cable. FIG. 4 is a cross-sectional view for describing a structure of the flexible flat cable in detail. FIGs. 5A to 5D are plan views of the main portion of the flexible flat cable for describing multiple types of impedance adjusters having different width dimensions.

[0022] A flexible flat cable 1 according to the present invention is, for example, applied to a movable component of a vehicle such as a steering roll connector serving as a rotary connector provided at a connection portion between a steering column on a vehicle body side and a steering shaft on a steering wheel side, a sliding door harness provided at a connection portion between the vehicle body side and a sliding door, or a sliding seat harness provided at a connection portion between the vehicle body side and a sliding seat. Alternatively, the flexible flat cable 1 is applied to a stationary component of a vehicle such as the interior of an ECU or a connection between ECUs. Furthermore, the flexible flat cable 1 according to the present invention is not limited to being applied to a vehicle and can be applied to an apparatus requiring communication between one device and another.

[0023] The flexible flat cable 1 has, for example, a width dimension of 5 mm or more and 30 mm or less, a thickness dimension of 0.1 mm or more and 0.3 mm or less, and a longitudinal dimension of 1000 mm. The flexible flat cable 1 forms a portion of a communication circuit for transmitting electrical signals between one device and another. Note here that the communication circuit is, for example, used in signal transmission based on a communication standard such as differential signal transmission employing Low Voltage Differential Signaling (LVDS) for performing high-speed transmission using low-voltage, low-amplitude signals, Controller Area Network (CAN), Controller Area Network Flexible Data Rate (CAN FD), Controller Area Network Extra Long (CAN XL), or Ethernet. The transmission rate of communication signals transmitted through the flexible flat cable 1 is generally 100 Mbps or less, but may be higher than 100 Mbps as necessary.

[0024] As shown in FIGs. 1 to 3, the flexible flat cable 1 includes: a first communication conductor 11 and a second communication conductor 12 that are spaced apart from each other by a predetermined spacing in the width direction; a plurality of impedance adjusters 13 that adjust the characteristic impedances of the first and second communication conductors 11 and 12; and an insulating material 14 that covers the first and second communication conductors 11 and 12.

[0025] Each of the first and second communication conductors 11 and 12 is composed of a material having high electrical conductivity, such as tough pitch copper. Each of the first and second communication conductors 11 and 12 has a strip shape with a rectangular transverse cross-section.

[0026] Each of the plurality of impedance adjusters 13 is, for example, composed of a metal having electrical conductivity such as copper or another conductive material such as carbon. The plurality of impedance adjusters 13 are disposed in at least a region corresponding to the spacing between the first and second communication conductors 11 and 12 at positions spaced apart from the first and second communication conductors 11 and 12 by a predetermined spacing in the thickness direction of the flexible flat cable 1, and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0027] In the present embodiment, each of the plurality of impedance adjusters 13 has a strip shape extending in the width direction of the flexible flat cable 1. Each of the plurality of impedance adjusters 13 extends from a centerline of the spacing between the first and second communication conductors 11 and 12 toward opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side.

[0028] The impedance adjusters 13 may be, for example, formed by generating a layer of a conductive material on an outer surface of the insulating material 14 through vapor deposition, sputtering, or plating, and subsequently performing etching. Alternatively, the impedance adjusters 13 may be, for example, directly formed on the outer surface of the insulating material 14 by screen printing, inkjet printing, or plating. Furthermore, the impedance adjusters 13 may be, for example, formed by attaching a plate-like member having portions removed by punching to the outer surface of the insulating material 14. The impedance adjusters 13 are formed to have a thickness dimension of, for example, 50 µm.

[0029] As shown in FIG. 4, the insulating material 14 includes a first base film 14a, a second base film 14b, and a third base film 14c, each of which is composed of an insulating material such as PET, as well as a first adhesive 14d, a second adhesive 14e, a third adhesive 14f, and a fourth adhesive 14g, each of which is a polyester-based adhesive.

[0030] In the flexible flat cable 1, the first and second communication conductors 11 and 12 are disposed between the first base film 14a and the second base film 14b with the first adhesive 14d and the second adhesive 14e therebetween, and the impedance adjusters 13 are disposed between the second base film 14b and the third base film 14c with the third adhesive 14f and the fourth adhesive 14g therebetween.

[0031] The characteristic impedances of the first and second communication conductors 11 and 12 are each adjusted to, for example, 100 Ω. In this case, the first and second communication conductors 11 and 12 are formed to have, for example, a width dimension of 0.8 mm and a thickness dimension of 35 µm, and spaced apart from each other by a spacing of 0.60 mm in the width direction of the flexible flat cable 1. The plurality of impedance adjusters 13 are spaced apart from the first and second communication conductors 11 and 12 by a spacing of, for example, 54 µm in the thickness direction of the flexible flat cable 1. Furthermore, each of the plurality of impedance adjusters 13 has a length of, for example, 0.25 mm in the short-side direction thereof (longitudinal direction of the flexible flat cable 1), and the interval between adjacent impedance adjusters 13 in the longitudinal direction of the first and second communication conductors 11 and 12 is, for example, 2.5 mm.

[0032] Note here that no limitations are imposed except that each of the plurality of impedance adjusters 13 has a length in the long-side direction thereof (width direction of the flexible flat cable 1) that is at least equal to the spacing between the first and second communication conductors 11 and 12. As shown in FIG. 5A, the impedance adjusters 13 may have a long-side length L1 equal to the spacing between the first and second communication conductors 11 and 12. As shown in FIG. 5B, the impedance adjusters 13 may have a long-side length L2 greater than the spacing between the first and second communication conductors 11 and 12, extending to respective centerlines of the first and second communication conductors 11 and 12 in the width direction. As shown in FIG. 5C, the impedance adjusters 13 may have a long-side length L3, extending to respective widthwise outer ends of the first and second communication conductors 11 and 12 paired in the width direction. As shown in FIG. 5D, the impedance adjusters 13 may have a long-side length L4, extending outward beyond the respective widthwise outer ends of the first and second communication conductors 11 and 12 paired in the width direction.

[0033] The flexible flat cable 1 having the above-described configuration forms a communication circuit between one device and another, with one end thereof connected to the one device and an opposite end thereof connected to the other device.

[0034] The plurality of impedance adjusters 13 are spaced apart from the first and second communication conductors 11 and 12 in the thickness direction, and are arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. The plurality of impedance adjusters 13 are allocated equally to both the first and second communication conductors 11 and 12. Thus, it is possible to adjust the characteristic impedances of the first and second communication conductors 11 and 12 to, for example, 100 Ω without introducing any difference therebetween.

[0035] As described above, the flexible flat cable according to the present embodiment is a flexible flat cable 1 including: a first communication conductor 11 and a second communication conductor 12 that are spaced apart from each other by a predetermined spacing in the width direction; and a plurality of impedance adjusters 13 that are composed of a conductive material and that adjust the characteristic impedances of the first and second communication conductors 11 and 12, the plurality of impedance adjusters 13 being disposed in at least a region corresponding to the spacing between the first and second communication conductors 11 and 12 at positions spaced apart from the first and second communication conductors 11 and 12 by a predetermined spacing in the thickness direction, and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0036] This configuration eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 13 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.

[0037] Preferably, each of the impedance adjusters 13 extends from a position corresponding to a centerline of the spacing between the first and second communication conductors 11 and 12 toward opposite widthwise edges by an equal distance on each side.

[0038] This configuration allows each of the impedance adjusters 13 to be allocated evenly to both the first and second communication conductors 11 and 12, making it possible to more reliably adjust the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value.

[0039] Preferably, opposite widthwise ends of each impedance adjuster 13 respectively extend at least to opposite widthwise ends of the first and second communication conductors 11 and 12 paired in the width direction.

[0040] This configuration allows the impedance adjusters 13, which are located outward of the first and second communication conductors 11 and 12 in the thickness direction, to be disposed across the width of the first and second communication conductors 11 and 12, making it possible to more reliably adjust the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value.

[0041] Preferably, the plurality of impedance adjusters 13 each have a strip shape with a predetermined width dimension and are arranged at predetermined intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0042] This configuration makes it possible to reduce the metal material usage as compared with a configuration having a metal layer formed to cover the entire flat surface of the flexible flat cable, thereby reducing manufacturing costs.<Second Embodiment>

[0043] FIG. 6 is a diagram illustrating a second embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0044] As shown in FIG. 6, each of a plurality of impedance adjusters 15 of the flexible flat cable 1 according to the present embodiment has a strip shape and extends in a direction inclined relative to the width direction and the longitudinal direction of the flexible flat cable 1. Each of the plurality of impedance adjusters 15 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side. Each of the plurality of impedance adjusters 15 extends, for example, at an angle of 15 degrees relative to the width direction of the flexible flat cable 1.

[0045] The plurality of impedance adjusters 15 of the flexible flat cable 1 having the above-described configuration each extend in a direction inclined relative to the width direction and the longitudinal direction of the flexible flat cable 1. However, the degree of inclination of the impedance adjusters 15 relative to the width direction and the longitudinal direction of the flexible flat cable 1 has little effect on the characteristic impedances of the first and second communication conductors 11 and 12 that extend in the longitudinal direction of the flexible flat cable 1. As such, the degree of inclination of the impedance adjusters 15 can be considered negligible in the flexible flat cable 1.

[0046] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 15 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Third Embodiment>

[0047] FIG. 7 is a diagram illustrating a third embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0048] As shown in FIG. 7, each of a plurality of impedance adjusters 16 of the flexible flat cable 1 according to the present embodiment has an elliptical shape. The major axis of each of the plurality of elliptical impedance adjusters 16 is oriented in the width direction of the flexible flat cable 1, and the minor axis thereof is oriented in the longitudinal direction of the flexible flat cable 1. Each of the plurality of impedance adjusters 16 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side.

[0049] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 16 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0050] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 16 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Fourth Embodiment>

[0051] FIG. 8 is a diagram illustrating a fourth embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0052] As shown in FIG. 8, each of a plurality of impedance adjusters 17 of the flexible flat cable 1 according to the present embodiment has a strip shape provided with a plurality of holes 17a. Each of the plurality of impedance adjusters 17 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side. Note here that the plurality of holes 17a may be provided in any number and at any positions in each impedance adjuster 17, provided that the size of each hole 17a is small enough that the effect thereof on the adjustment of the characteristic impedances of the first and second communication conductors 11 and 12 is negligible. On the other hand, if the size of each hole 17a is so large that the effect thereof on the adjustment of the characteristic impedances of the first and second communication conductors 11 and 12 is not negligible, it is necessary to provide a certain number of holes 17a at certain positions in each impedance adjuster 17 so that the holes 17a are equally distributed to both the first communication conductor 11 side and the second communication conductor 12 side based on the midpoint between the first and second communication conductors 11 and 12 in the width direction of the flexible flat cable 1.

[0053] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 17 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0054] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 17 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Fifth Embodiment>

[0055] FIG. 9 is a diagram illustrating a fifth embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0056] As shown in FIG. 9, each of a plurality of impedance adjusters 18 of the flexible flat cable 1 according to the present embodiment has a strip shape and extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side. The flexible flat cable 1 further includes connecting parts 18a that integrally connect ends of the plurality of impedance adjusters 18 on each side.

[0057] The connecting parts 18a are composed of the same material as the impedance adjusters 18. The connecting parts 18a are located toward the opposite widthwise outer edges of the flexible flat cable 1 and extend in the longitudinal direction of the flexible flat cable 1. The connecting parts 18a are connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected, and equalize the potentials of the plurality of impedance adjusters 18 connected to the connecting parts 18a.

[0058] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 18 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. Furthermore, since the plurality of impedance adjusters 18 are connected to a ground via the connecting parts 18a, the flexible flat cable 1 makes it possible to stabilize the potentials of the plurality of impedance adjusters 18.

[0059] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 18 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.

[0060] Preferably, the flexible flat cable 1 further includes the connecting parts 18a composed of a conductive material and located, in the width direction, outward of the first and second communication conductors 11 and 12 paired in the width direction, and the connecting parts 18a extend in the longitudinal direction of the first and second communication conductors 11 and 12 and connect the impedance adjusters 18 to each other.

[0061] This configuration makes it possible to stabilize the potentials of the plurality of impedance adjusters 18, thereby enhancing communication performance.<Sixth Embodiment>

[0062] FIGs. 10 and 11A to 11C are diagrams illustrating a sixth embodiment of the present invention. FIG. 10 is a plan view of a main portion of a flexible flat cable. FIGs. 11A to 11C are plan views of the main portion of the flexible flat cable for describing multiple types of impedance adjusters having different width dimensions.

[0063] As shown in FIG. 10, each of a plurality of impedance adjusters 19 of the flexible flat cable 1 according to the present embodiment has a strip shape and extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side. The flexible flat cable 1 further includes connecting parts 19a that integrally connect ends of the plurality of impedance adjusters 19 on each side.

[0064] The connecting parts 19a are composed of the same material as the impedance adjusters 19, and extend in the longitudinal direction of the flexible flat cable 1 and respectively span the entire surfaces of regions from the opposite ends of the impedance adjusters 19 to the opposite widthwise outer edges of the flexible flat cable 1. The connecting parts 19a are connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected, and equalize the potentials of the plurality of impedance adjusters 19 connected to the connecting parts 19a.

[0065] Furthermore, no limitations are imposed except that each of the plurality of impedance adjusters 19 has a length in the long-side direction thereof (width direction of the flexible flat cable 1) that extends outward at least beyond the widthwise outer ends of the paired first and second communication conductors 11 and 12. The extent to which the long-side length of the impedance adjusters 19 extends outward beyond the widthwise outer ends of the paired first and second communication conductors 11 and 12 may be varied as indicated by L1, L2, and L3 in FIGs. 11A, 11B, and 11C. In this case, the characteristic impedances of the first and second communication conductors 11 and 12 increase as the long-side length of the impedance adjusters 19 increases, but the amount of increase decreases once the long-side length exceeds a certain value.

[0066] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 19 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. Furthermore, since the plurality of impedance adjusters 19 are connected to a ground via the connecting parts 19a, the flexible flat cable 1 makes it possible to stabilize the potentials of the plurality of impedance adjusters 19.

[0067] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 19 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Seventh Embodiment>

[0068] FIG. 12 is a diagram illustrating a seventh embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0069] As shown in FIG. 12, each of a plurality of impedance adjusters 20 of the flexible flat cable 1 according to the present embodiment has a strip shape. Each of the plurality of impedance adjusters 20 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1, and has one end and an opposite end in the width direction of the flexible flat cable 1. The plurality of impedance adjusters 20 include a plurality of first adjusters 20a and a plurality of second adjusters 20b. The one end of each first adjuster 20a extends farther than the opposite end thereof. The opposite end of each second adjuster 20b extends farther than the one end thereof. The first adjusters 20a and the second adjusters 20b are alternately arranged in the longitudinal direction of the flexible flat cable 1.

[0070] The flexible flat cable 1 further includes a first connecting part 20c that integrally connects the plurality of first adjusters 20a and a second connecting part 20d that integrally connects the plurality of second adjusters 20b.

[0071] The first connecting part 20c is composed of the same material as the first adjusters 20a. The first connecting part 20c is located toward one widthwise edge of the flexible flat cable 1 and extends in the longitudinal direction of the flexible flat cable 1. The first connecting part 20c is connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected and equalizes the potentials of the plurality of first adjusters 20a.

[0072] The second connecting part 20d is composed of the same material as the second adjusters 20b. The second connecting part 20d is located toward an opposite widthwise edge of the flexible flat cable 1 and extends in the longitudinal direction of the flexible flat cable 1. The second connecting part 20d is connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected and equalizes the potentials of the plurality of second adjusters 20b.

[0073] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 20 (first and second adjusters 20a and 20b) spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. Furthermore, since the plurality of impedance adjusters 20 (first and second adjusters 20a and 20b) are connected to a ground via the first and second connecting parts 20c and 20d, the flexible flat cable 1 makes it possible to stabilize the potentials of the plurality of impedance adjusters 20.

[0074] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 20 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Eighth Embodiment>

[0075] FIG. 13 is a diagram illustrating an eighth embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0076] As shown in FIG. 13, each of a plurality of impedance adjusters 21 of the flexible flat cable 1 according to the present embodiment has a strip shape. Each of the plurality of impedance adjusters 21 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1, and has one end and an opposite end in the width direction of the flexible flat cable 1. The plurality of impedance adjusters 21 include a plurality of first adjusters 21a, a plurality of second adjusters 21b, and a third adjuster 21c. The one end of each first adjuster 21a extends farther than the opposite end thereof. The opposite end of each second adjuster 21b extends farther than the one end thereof. The third adjuster 21c extends toward the opposite widthwise edges of the flexible flat cable 1 by an equal length on each side. The first adjusters 21a and the second adjusters 21b are alternately arranged in the longitudinal direction of the flexible flat cable 1. The first adjusters 21a and the second adjusters 21b alternately arranged in the longitudinal direction of the flexible flat cable 1 have at least one third adjuster 21c therebetween.

[0077] The flexible flat cable 1 further includes a first connecting part 21d that integrally connects the plurality of first adjusters 21a and a second connecting part 21e that integrally connects the plurality of second adjusters 21b.

[0078] The first connecting part 21d is composed of the same material as the first adjusters 21a. The first connecting part 21d is located toward one widthwise edge of the flexible flat cable 1 and extends in the longitudinal direction of the flexible flat cable 1.

[0079] The second connecting part 21e is composed of the same material as the second adjusters 21b. The second connecting part 21e is located toward an opposite widthwise edge of the flexible flat cable 1 and extends in the longitudinal direction of the flexible flat cable 1.

[0080] The third adjuster 21c connects the first connecting part 21d and the second connecting part 21e to each other. At least one of the first connecting part 21d or the second connecting part 21e is connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected and equalizes the potentials of the plurality of impedance adjusters 21 (first, second, and third adjusters 21a, 21b, and 21c).

[0081] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 21 (first, second, and third adjusters 21a, 21b, and 21c) spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. Furthermore, since the plurality of impedance adjusters 21 (first, second, and third adjusters 21a, 21b, and 21c) are connected to a ground via the first and second connecting parts 21d and 21e, the flexible flat cable 1 makes it possible to stabilize the potentials of the plurality of impedance adjusters 21 (first, second, and third adjusters 21a, 21b, and 21c).

[0082] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 21 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Ninth Embodiment>

[0083] FIG. 14 is a diagram illustrating a ninth embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0084] As shown in FIG. 14, a plurality of impedance adjusters 22 and a connecting part 22a of the flexible flat cable 1 according to the present embodiment are spaced apart from the first and second communication conductors 11 and 12 in the thickness direction, and are formed from a metal layer 23, which serves as a conductive layer, extending in the longitudinal direction of the first and second communication conductors 11 and 12, and having a plurality of openings 23a arranged in the longitudinal direction of the first and second communication conductors 11 and 12.

[0085] The plurality of impedance adjusters 22 are formed between adjacent openings 23a in the metal layer 23. As in the case of the first embodiment, each of the plurality of impedance adjusters 22 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1.

[0086] The metal layer 23 is connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected, and thus the potentials of the plurality of impedance adjusters 21 are equalized.

[0087] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 22 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. Furthermore, since the plurality of impedance adjusters 22 are connected to a ground via the connecting part 22a, the flexible flat cable 1 makes it possible to stabilize the potentials of the plurality of impedance adjusters 22.

[0088] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 22 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.

[0089] Furthermore, preferably, the impedance adjusters 22 and the connecting part 22a are formed from the metal layer 23, which serves as a conductive layer, extending in the longitudinal direction of the first and second communication conductors 11 and 12, and having the plurality of openings 23a arranged in the longitudinal direction of the first and second communication conductors 11 and 12.

[0090] This configuration makes it possible to form the impedance adjusters 22 and the connecting part 22a using a simple configuration of a single metal layer 23, thereby reducing manufacturing costs.<Tenth Embodiment>

[0091] FIG. 15 is a diagram illustrating a tenth embodiment of the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0092] As shown in FIG. 15, the flexible flat cable 1 according to the present embodiment includes a plurality of adjuster units 24 each including multiple types of impedance adjusters 24a, 24b, 24c, 24d, and 24e that are different in length in the short-side direction thereof (longitudinal direction of the flexible flat cable 1) and that are arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0093] The plurality of adjuster units 24 are arranged in the longitudinal direction of the first and second communication conductors 11 and 12. The plurality of adjuster units 24 are integrated by connecting opposite ends of the multiple types of impedance adjusters 24a, 24b, 24c, 24d, and 24e on each side using connecting parts 24f.

[0094] The connecting parts 24f are composed of the same material as the impedance adjusters 24a, 24b, 24c, 24d, and 24e. The connecting parts 24f extend in the longitudinal direction of the flexible flat cable 1 and respectively span the entire surfaces of regions from the opposite ends of the impedance adjusters 24a, 24b, 24c, 24d, and 24e to the opposite widthwise outer edges of the flexible flat cable 1. The connecting parts 24f are connected to a ground such as one on a housing of a device to which the flexible flat cable 1 is connected, and equalize the potentials of the impedance adjusters 24a, 24b, 24c, 24d, and 24e connected to the connecting parts 24f.

[0095] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of adjuster units 24 each including the multiple types of impedance adjusters 24a, 24b, 24c, 24d, and 24e spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. Furthermore, since the multiple types of impedance adjusters 24a, 24b, 24c, 24d, and 24e are connected to a ground via the connecting parts 24f, the flexible flat cable 1 makes it possible to stabilize the potentials of the multiple types of impedance adjusters 24a, 24b, 24c, 24d, and 24e in the plurality of adjuster units 24.

[0096] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 24a, 24b, 24c, 24d, and 24e is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.

[0097] The flexible flat cable according to the present embodiment includes the plurality of adjuster units 24 each including the multiple impedance adjusters 24a, 24b, 24c, 24d, and 24e arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12, and the plurality of adjuster units 24 are arranged in the longitudinal direction of the first and second communication conductors 11 and 12.

[0098] This configuration allows each adjuster unit 24 including the multiple impedance adjusters 24a, 24b, 24c, 24d, and 24e to be handled as a single component, making it possible to reduce the amount of labor required for assembly.<Eleventh Embodiment>

[0099] FIG. 16 is a diagram illustrating an eleventh embodiment of the present invention and is a cross-sectional view of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0100] As shown in FIG. 16, the flexible flat cable 1 according to the present embodiment includes additional conductors 25 located, with a spacing in the width direction, outward of the first and second communication conductors 11 and 12 paired in the width direction. The conductors 25 are, for example, used for transmitting electric power between one device and another.

[0101] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 13 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12.

[0102] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 13 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.<Twelfth Embodiment>

[0103] FIG. 17 is a diagram illustrating a twelfth embodiment of the present invention and is a cross-sectional view of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0104] As shown in FIG. 17, the flexible flat cable 1 according to the present embodiment includes a pair of ground conductors 26 located, with a spacing in the width direction, outward of the first and second communication conductors 11 and 12 paired in the width direction.

[0105] In the flexible flat cable 1 having the above-described configuration, the characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by the plurality of impedance adjusters 13 spaced apart from the first and second communication conductors 11 and 12 in the thickness direction and arranged at intervals in the longitudinal direction of the first and second communication conductors 11 and 12. The characteristic impedances of the first and second communication conductors 11 and 12 are adjusted by changing the spacing between the ground conductors 26 and the first and second communication conductors 11 and 12.

[0106] Thus, as in the case of the first embodiment, the flexible flat cable according to the present embodiment eliminates the need for a metal layer that covers the entire flat surface, making it possible to minimize an increase in size in the thickness direction, and thus ensure flexibility. Furthermore, since each of the plurality of impedance adjusters 13 is allocated equally to both the first and second communication conductors 11 and 12, this configuration makes it possible to adjust each of the characteristic impedances of the first and second communication conductors 11 and 12 to a predetermined value without introducing any difference therebetween.

[0107] It should be noted that the cross-sectional shapes of the first and second communication conductors 11 and 12 are rectangular in the foregoing embodiments, but are not limited as such. As the cross-sectional shapes, the first and second communication conductors may have a rectangular transverse cross-sectional shape as shown in FIG. 18A or a circular transverse cross-sectional shape as shown in FIG. 18B. Alternatively, the first and second communication conductors may each be a twisted wire formed by twisting thin conductive strands as shown in FIG. 18C. Moreover, the first communication conductor 11 and the second communication conductor may have different transverse cross-sectional shapes, as long as the first and second communication conductors have substantially the same conductor resistance.

[0108] In the first embodiment, as shown in FIG. 3, the impedance adjusters 13 are disposed on the outer surface of the insulating material 14 that covers the first and second communication conductors 11 and 12. However, the impedance adjusters 13 are not limited as such. The impedance adjusters 13 may be embedded within the insulating material 14 as shown in FIG. 19, as long as the impedance adjusters 13 are disposed at positions spaced apart from the first and second communication conductors 11 and 12 by a predetermined spacing in the thickness direction of the flexible flat cable 1. Alternatively, the impedance adjusters 13 may be embedded in the insulating material 14 so that outer surfaces thereof are flush with the outer surface of the insulating material 14 as shown in FIG. 20. Alternatively, a portion of each of the impedance adjusters 13 including the outer surface thereof may project from the insulating material 14, and the remaining portion may be embedded within the insulating material 14 as shown in FIG. 21.

[0109] The flexible flat cables 1 described in the foregoing embodiments are applicable to electric power supply devices described in detail in thirteenth to fifteenth embodiments below. Each electric power supply device transmits at least one of electric power or electrical signals between one member and another, and includes a flexible flat cable. One end of the flexible flat cable is connected to the one member, and an opposite end of the flexible flat cable is connected to the other member.<Thirteenth Embodiment>

[0110] FIG. 22 is a diagram illustrating the thirteenth embodiment of the present invention and is a perspective view of a main portion of an electric power supply device. It should be noted that the same elements of configuration as in the first to twelfth embodiments are labeled with the same reference numerals as in the first to twelfth embodiments.

[0111] With respect to the present embodiment, the following describes, as an example of an application for the flexible flat cable 1, an electric power supply device 100 for a sliding door that transmits at least one of electric power or electrical signals between a vehicle body B as one member of a vehicle and a sliding door D as another member.

[0112] The electric power supply device 100 includes a flexible flat cable 1.

[0113] A connector 2 is connected to each of the opposite ends of the flexible flat cable 1.

[0114] One end of the flexible flat cable 1 is connected to the vehicle body B via the connector 2.

[0115] The opposite end of the flexible flat cable 1 is connected to the sliding door D via the connector 2.

[0116] That is, the flexible flat cable 1 connects an electrical circuit provided on the vehicle body B side with an electrical circuit provided on the sliding door D side.

[0117] The flexible flat cable 1 installed between the vehicle body B and the sliding door D extends in one direction along the moving direction of the sliding door D, is curved into a U-shape to reverse direction, and extends in an opposite direction along the moving direction of the sliding door D. In this embodiment, a portion of the flexible flat cable 1 curved into a U-shape to reverse direction is defined as a reversal portion 1a.

[0118] In the electric power supply device 100 having the above-described configuration, when the sliding door D is opened or closed, only the position of the reversal portion 1a in the lengthwise direction changes, while the directions in which the flexible flat cable 1 extends are maintained.

[0119] As such, the flexible flat cable 1 transmits at least one of electric power or electrical signals between the vehicle body B and the sliding door D without interfering with the movement of the sliding door D relative to the vehicle body B.

[0120] As described above, the electric power supply device according to the present embodiment is an electric power supply device 100 for transmitting at least one of electric power or electrical signals between a vehicle body B and a sliding door D. The electric power supply device 100 includes a flexible flat cable 1. One end of the flexible flat cable 1 is connected to the vehicle body B, and an opposite end of the flexible flat cable 1 is connected to the sliding door D.

[0121] This configuration makes it possible to enhance communication performance in high-speed communication between the vehicle body B and the sliding door D since the flexible flat cable 1, which includes the first and second communication conductors 11 and 12 with adjusted characteristic impedances, is used to transmit at least one of electric power or electrical signals between the vehicle body B and the sliding door D.

[0122] The sliding door D is movable relative to the vehicle body B.

[0123] Using the flexible flat cable 1 as wiring to connect the vehicle body B and the sliding door D makes it possible to transmit at least one of electric power or electrical signals without interfering with the movement of the sliding door D relative to the vehicle body B.<Fourteenth Embodiment>

[0124] FIG. 23 is a diagram illustrating the fourteenth embodiment of the present invention and is a perspective view of a main portion of an electric power supply device. It should be noted that the same elements of configuration as in the first to thirteenth embodiments are labeled with the same reference numerals as in the first to thirteenth embodiments.

[0125] With respect to the present embodiment, the following describes, as an example of an application for the flexible flat cable 1, an electric power supply device 200 for a sliding seat that transmits at least one of electric power or electrical signals between a vehicle body B as one member of a vehicle and a sliding seat S as another member.

[0126] The electric power supply device 200 includes a flexible flat cable 1.

[0127] A connector 2 is connected to each of the opposite ends of the flexible flat cable 1.

[0128] The vehicle body B has a connector BC that forms an electrical circuit on the vehicle body B side. One end of the flexible flat cable 1 is connected to the connector BC via the connector 2.

[0129] The sliding seat S has a connector SC that forms an electrical circuit on the sliding seat S side. The opposite end of the flexible flat cable 1 is connected to the connector SC via the connector 2.

[0130] That is, the flexible flat cable 1 connects the electrical circuit provided on the vehicle body B side with the electrical circuit provided on the sliding seat S side.

[0131] The flexible flat cable 1 installed between the vehicle body B and the sliding seat S extends upward from the vehicle body B, bends in the horizontal direction, extends in one direction along the moving direction of the sliding seat S, reverses direction through a reversal portion 1a, and extends in an opposite direction along the moving direction of the sliding seat S.

[0132] In the electric power supply device 200 having the above-described configuration, when the sliding seat S moves in the front-rear direction, only the position of the reversal portion 1a in the lengthwise direction changes, while the orientation in which the flexible flat cable 1 extends along the moving direction of the sliding seat S is maintained.

[0133] As such, the flexible flat cable 1 transmits at least one of electric power or electrical signals between the vehicle body B and the sliding seat S without interfering with the movement of the sliding seat S relative to the vehicle body B.

[0134] As described above, the electric power supply device according to the present embodiment is an electric power supply device 200 for transmitting at least one of electric power or electrical signals between a vehicle body B and a sliding seat S. The electric power supply device 200 includes a flexible flat cable 1. One end of the flexible flat cable 1 is connected to the vehicle body B, and an opposite end of the flexible flat cable 1 is connected to the sliding seat S.

[0135] This configuration makes it possible to enhance communication performance in high-speed communication between the vehicle body B and the sliding seat S since the flexible flat cable 1, which includes the first and second communication conductors 11 and 12 with adjusted characteristic impedances, is used to transmit at least one of electric power or electrical signals between the vehicle body B and the sliding seat S.

[0136] The sliding seat S is movable relative to the vehicle body B.

[0137] Using the flexible flat cable 1 as wiring to connect the vehicle body B and the sliding seat S makes it possible to transmit at least one of electric power or electrical signals without interfering with the movement of the sliding seat S relative to the vehicle body B.<Fifteenth Embodiment>

[0138] FIGs. 24 and 25 are diagrams illustrating the fifteenth embodiment of the present invention. FIG. 24 is a perspective view of a steering roll connector, and FIG. 25 is a plan view illustrating an internal structure of the steering roll connector. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0139] With respect to the present embodiment, the following describes, as an example of an application for the flexible flat cable 1, a steering roll connector 300 that is used as an electric power supply device to be provided at a connection portion between a steering column on a vehicle body side and a steering shaft on a steering wheel side in a vehicle.

[0140] The steering roll connector 300 transmits at least one of electric power or electrical signals between a device provided on the steering wheel connected to the steering shaft rotatable relative to the vehicle body and a device provided on the vehicle body.

[0141] As shown in FIGs. 24 and 25, the steering roll connector 300 includes a plurality of flexible flat cables 1, a fixed-side housing 310 as one member, which is fixed to the steering column, and a rotating-side housing 320 as another member, which is fixed to the steering shaft.

[0142] The fixed-side housing 310 includes a fixed-side ring part 311 having an opening through which the steering shaft can be inserted, and a cylindrical outer peripheral part 312 having a hollow cylindrical shape extending vertically from the outer periphery of the fixed-side ring part 311. The outer periphery of the cylindrical outer peripheral part 312 is provided with a first fixed-side connector 313 to which one end of at least one of the plurality of flexible flat cables 1 is connected, and a second fixed-side connector 314 to which one end of each of the remaining flexible flat cables 1 is connected.

[0143] The rotating-side housing 320 includes a rotating-side ring part 321 disposed to face the fixed-side ring part 311 and provided with an opening through which the steering shaft can be inserted, and a cylindrical inner peripheral part 322 disposed to face the cylindrical outer peripheral part 312 and having a hollow cylindrical shape extending vertically from the inner periphery of the rotating-side ring part 321. The outer surface of the rotating-side ring part 321 is provided with a first rotating-side connector 323 to which an opposite end of the at least one of the plurality of flexible flat cables 1 having the one end connected to the first fixed-side connector 313 is connected, and a second rotating-side connector 324 to which an opposite end of each of the remaining flexible flat cables 1 having the one end connected to the second fixed-side connector 314 is connected.

[0144] As shown in FIG. 25, an accommodating space S that accommodates the plurality of flexible flat cables 1 is formed between the fixed-side housing 310 and the rotating-side housing 320. The accommodating space S has an annular shape defined by the fixed-side ring part 311 and the cylindrical outer peripheral part 312 of the fixed-side housing 310, and the rotating-side ring part 321 and the cylindrical inner peripheral part 322 of the rotating-side housing 320.

[0145] The plurality of flexible flat cables 1, which are arranged in layers and separable from each other, are accommodated in the accommodating space S. Each of the plurality of flexible flat cables 1 is fixed to the cylindrical outer peripheral part 312 at the one end thereof, wound along the inner surface of the cylindrical outer peripheral part 312 in one direction along the rotation direction of the rotating-side housing 320, curved into a U-shape at a middle portion thereof to reverse direction between the cylindrical outer peripheral part 312 and the cylindrical inner peripheral part 322, wound in an opposite direction along the rotation direction, and fixed to the cylindrical inner peripheral part 322 at the opposite end thereof.

[0146] As shown in FIG. 25, the middle portion of each of the plurality of flexible flat cables 1 accommodated in the accommodating space S has a reversal portion 1a that moves as the rotating-side housing 320 rotates relative to the fixed-side housing 310. When each of the reversal portions 1a is located at the center of the corresponding flexible flat cable 1 in the longitudinal direction, the rotating-side housing 320 is allowed to rotate relative to the fixed-side housing 310 by the same angle in the one direction and in the opposite direction.

[0147] In the steering roll connector 300 having the above-described configuration, the rotating-side housing 320 rotates relative to the fixed-side housing 310 as the steering shaft rotates.

[0148] During the rotation, the reversal portions 1a of the flexible flat cables 1 maintain the direction-reversing state and move within the annular accommodating space S. As such, the flexible flat cables 1 transmit at least one of electric power or electrical signals between the vehicle body side, to which the fixed-side housing 310 is fixed, and the steering shaft side, to which the rotating-side housing 320 is fixed, without interfering with the rotation of the rotating-side housing 320 relative to the fixed-side housing 310.

[0149] As described above, the electric power supply device according to the present embodiment is a steering roll connector 300 for transmitting at least one of electric power or electrical signals between a fixed-side housing 310 and a rotating-side housing 320. The steering roll connector 300 includes a plurality of flexible flat cables 1. One end of each flexible flat cable 1 is connected to the fixed-side housing 310, and an opposite end of each flexible flat cable 1 is connected to the rotating-side housing 320.

[0150] This configuration makes it possible to enhance communication performance in high-speed communication between the vehicle body and the steering wheel since the flexible flat cables 1, which each include the first and second communication conductors 11 and 12 with adjusted characteristic impedances, are used to transmit at least one of electric power or electrical signals between the fixed-side housing 310 and the rotating-side housing 320.

[0151] Furthermore, the rotating-side housing 320 is rotatable relative to the fixed-side housing 310.

[0152] Using the flexible flat cables 1 as wiring to connect the fixed-side housing 310 and the rotating-side housing 320 makes it possible to transmit at least one of electric power or electrical signals without interfering with the rotational movement of the rotating-side housing 320 relative to the fixed-side housing 310.<Sixteenth Embodiment>

[0153] FIG. 26 is a diagram illustrating the sixteenth embodiment of the present invention and is a plan view of a main portion of a flexible flat cable for illustrating a connection structure thereof. It should be noted that the same elements of configuration as in the first to fifteenth embodiments are labeled with the same reference numerals as in the first to fifteenth embodiments.

[0154] The flexible flat cable 1 including a connection structure according to the present embodiment is connected to a conductive circuit and a communication circuit via a connector 400. As shown in FIG. 26, each of the first and second communication conductors 11 and 12 of the flexible flat cable 1 is connected to a bus bar 410, which is a connection target forming the connector 400. The bus bars 410 are, for example, members having electrical conductivity such as brass.

[0155] In the present embodiment, the connection structure is applied to the connection between the first and second communication conductors 11 and 12 and the respective bus bars 410.

[0156] The connection structure includes connection portions 420, which are portions of the first and second communication conductors 11 and 12 of the flexible flat cable 1 that are connected to the bus bars 410. The connection portions 420 are located at respective ends of the first and second communication conductors 11 and 12.

[0157] The connection portions 420 are formed by joining the first and second communication conductors 11 and 12 to the bus bars 410 by ultrasonic welding, resistance welding, or soldering. The flexible flat cable 1 including the connection structure according to the present embodiment can be, for example, used by being incorporated in any of the electric power supply devices according to the thirteenth to fifteenth embodiments of the present invention described above.EXPLANATION OF REFERENCE NUMERALS

[0158] 1: Flexible flat cable 11: First communication conductor 12: Second communication conductor 13, 15, 16, 17, 18: Impedance adjuster 18a, 19a: Connecting part 20: Impedance adjuster 20a: First adjuster 20b: Second adjuster 20c: First connecting part 20d: Second connecting part 21: Impedance adjuster 21a: First adjuster 21b: Second adjuster 21d: First connecting part 21e: Second connecting part 22: Impedance adjuster 23: Metal layer 23a: Opening 24: Adjuster unit 24a, 24b, 24c, 24d, 24e: Impedance adjuster 100, 200: Electric power supply device 300: Steering roll connector 310: Fixed-side housing 320: Rotating-side housing B: Vehicle body D: Sliding door S: Sliding seat

Examples

first embodiment

[0021]FIGs. 1 to 5D are diagrams for illustrating the present invention. FIG. 1 is a plan view of a flexible flat cable. FIG. 2 is a plan view of a main portion of the flexible flat cable. FIG. 3 is a cross-sectional view of the flexible flat cable. FIG. 4 is a cross-sectional view for describing a structure of the flexible flat cable in detail. FIGs. 5A to 5D are plan views of the main portion of the flexible flat cable for describing multiple types of impedance adjusters having different width dimensions.

[0022]A flexible flat cable 1 according to the present invention is, for example, applied to a movable component of a vehicle such as a steering roll connector serving as a rotary connector provided at a connection portion between a steering column on a vehicle body side and a steering shaft on a steering wheel side, a sliding door harness provided at a connection portion between the vehicle body side and a sliding door, or a sliding seat harness provided at a connection portion b...

sixth embodiment

[0062]FIGs. 10 and 11A to 11C are diagrams illustrating the present invention. FIG. 10 is a plan view of a main portion of a flexible flat cable. FIGs. 11A to 11C are plan views of the main portion of the flexible flat cable for describing multiple types of impedance adjusters having different width dimensions.

[0063]As shown in FIG. 10, each of a plurality of impedance adjusters 19 of the flexible flat cable 1 according to the present embodiment has a strip shape and extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1 by an equal length on each side. The flexible flat cable 1 further includes connecting parts 19a that integrally connect ends of the plurality of impedance adjusters 19 on each side.

[0064]The connecting parts 19a are composed of the same material as the impedance adjusters 19, and extend in the longitudinal direction of the flexible flat cable 1...

eighth embodiment

[0075]FIG. 13 is a diagram illustrating the present invention and is a plan view of a main portion of a flexible flat cable. It should be noted that the same elements of configuration as in the first embodiment are labeled with the same reference numerals as in the first embodiment.

[0076]As shown in FIG. 13, each of a plurality of impedance adjusters 21 of the flexible flat cable 1 according to the present embodiment has a strip shape. Each of the plurality of impedance adjusters 21 extends from the centerline of the spacing between the first and second communication conductors 11 and 12 toward the opposite widthwise outer edges of the flexible flat cable 1, and has one end and an opposite end in the width direction of the flexible flat cable 1. The plurality of impedance adjusters 21 include a plurality of first adjusters 21a, a plurality of second adjusters 21b, and a third adjuster 21c. The one end of each first adjuster 21a extends farther than the opposite end thereof. The oppo...

Claims

1. A flexible flat cable comprising: a first communication conductor and a second communication conductor that are spaced apart from each other by a predetermined spacing in a width direction; and a plurality of impedance adjusters that are composed of a conductive material and that adjust characteristic impedances of the first and second communication conductors, the plurality of impedance adjusters being disposed in at least a region corresponding to the spacing between the first and second communication conductors at positions spaced apart from the first and second communication conductors by a predetermined spacing in a thickness direction, and arranged at intervals in a longitudinal direction of the first and second communication conductors.

2. The flexible flat cable according to claim 1, wherein each of the impedance adjusters extends from a position corresponding to a centerline of the spacing between the first and second communication conductors toward opposite widthwise edges by an equal distance on each side.

3. The flexible flat cable according to claim 2, wherein opposite widthwise ends of each of the impedance adjusters respectively extend at least to opposite widthwise ends of the first and second communication conductors paired in the width direction.

4. The flexible flat cable according to claim 3, further comprising a connecting part composed of a conductive material and located, in the width direction, outward of the first and second communication conductors paired in the width direction, the connecting part extending in the longitudinal direction of the first and second communication conductors and connecting the impedance adjusters to each other.

5. The flexible flat cable according to claim 4, wherein the impedance adjusters and the connecting part are formed from a conductive layer extending in the longitudinal direction of the first and second communication conductors and having a plurality of openings arranged in the longitudinal direction of the first and second communication conductors.

6. The flexible flat cable according to claim 3, wherein the plurality of impedance adjusters each have a strip shape with a predetermined width dimension and are arranged at predetermined intervals in the longitudinal direction of the first and second communication conductors.

7. The flexible flat cable according to claim 3, comprising a plurality of adjuster units each including multiple ones of the plurality of impedance adjusters arranged at intervals in the longitudinal direction of the first and second communication conductors, wherein the plurality of adjuster units are arranged in the longitudinal direction of the first and second communication conductors.

8. An electric power supply device for transmitting at least one of electric power or an electrical signal between one member and another, the electric power supply device comprising the flexible flat cable according to any one of claims 1 to 7, wherein one end of the flexible flat cable is connected to the one member, and an opposite end of the flexible flat cable is connected to the other member.

9. The electric power supply device according to claim 8, wherein the one member is movable relative to the other member.

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