This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2011-110651, filed on May 17, 2011, the entire contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a cable connection structure in which a cable is connected to a board, and a cable connection board.
2. Description of the Related Art
Conventionally, a medical endoscope enables an observation of a lesion site when an insertion unit is deeply inserted to an inside of a body and further enables an examination and a medical treatment in the inside of the body by using a treatment tool together depending on a necessity. As such an endoscope, there is an endoscope provided with an imaging device in which an imaging element such as a CCD is embedded at a distal end of the insertion unit. The endoscope is configured by embedding an imaging module on which an imaging device is mounted in the distal end part of the elongated insertion unit having flexibility and enables an observation and the like of a test site when the insertion unit is inserted in an inside of a body cavity. The distal end part of the insertion unit has been desired to be thinner, shorter, and smaller to ease a pain of a patient.
As a technique for solving the problem, a technique for challenging an improvement in density of signal cables by folding a flexible board connected to an imaging device in half and the like are disclosed in Japanese Patent Application Laid-Open No. H04-197334, for example.
Besides, an electronic endoscope provided with a signal wire fixation groove which fixes a signal wire of a cable on a circuit board in the vicinity of a signal wire connection terminal part is disclosed in Japanese Patent Application Laid-Open No. 2006-14906, for example.
However, it is only possible in the technique disclosed in Japanese Patent Application Laid-Open No. H04-197334 to connect core wires at the same alignment pitch as signal cables on the flexible board. The alignment pitch of cables is generally a pitch aligned by a jig or a pitch aligned at a state where cables are in contact with each other by their outer coverings, and cables are fixed at the aligned state by a lamination and the like, for example. On this occasion, it is at least impossible to connect core wires at a pitch not more than the outermost diameter of the cable. Therefore, there is a restriction of a layout in mounting on a board.
Besides, it is only possible in the technique disclosed in Japanese Patent Application Laid-Open No. 2006-14906 to connect cables at a pitch aligned by their outer covering parts while there is an advantage of being able to prevent a misalignment of signal wires. Moreover, it is difficult to make a dimension small since a circuit board is connected to an imaging device via a wire lead and the like.
According to an aspect of the present invention, in a cable connection structure in which a cable and a board provided with a connecting electrode to which the cable is connected are connected, the board includes at least two protruding parts constituting a groove part in which a conducting body of the cable is arranged on the connecting electrode, the protruding parts include a fixed protruding part which does not fuse in soldering the conducting body onto the connecting electrode, and an extending direction of the conducting body arranged in the groove part is not aligned with an extending direction of the cable.
The above and other features, advantages, and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings.
Exemplary embodiments of a cable connection structure according to the present invention will be explained below with reference to the accompanying drawings. It should be noted that the present invention is not limited to the embodiments. The same part is assigned with the same reference symbol in the description of the drawings.
The cable 2 is provided with a conducting body 21 as a core wire and an outer covering 22 as an insulating body provided in an outer circumference of the conducting body 21. The board 1 is provided with a connecting electrode 10 to which the conducting body 21 of the cable 2 is connected. While the board 1 shown in
On each connecting electrode 10, two hemispherical protruding parts 11 are formed and arranged. As shown in
In the first embodiment, the groove part 16 is formed so that an extending direction Y of the conducting body 21 arranged in the groove part 16 as shown in
Besides, the connecting electrode 10 and the protruding parts 11 are formed so that an alignment pitch b of the conducting bodies 21 becomes narrower than an alignment pitch a of the cables 2 in the first embodiment. By folding and arranging in the groove part 16 the conducting part 21 of the cable 2 on the board 1 formed in this manner, providing a joint member such as a solder to a joint part between the conducting part 21 and the connecting electrode 10, and heating, by a heating tool and the like, the joint member to cause fusion for connection, the alignment pitch b of the conducting bodies 21 is made narrower than the alignment pitch a of the cables 2.
It is preferable that a height R of the protruding part 11 is more than a diameter 2r of the conducting body 21 of the cable 2 in the first embodiment. By making the height R of the protruding part 11 more than the diameter 2r of the conducting body 21, the fixation of the conducting body 21 can be performed easily. In jointing the conducting body 21 and the connecting electrode 10 by heating the joint member such as a solder to cause fusion by a heating tool and the like, for example, the height R of the protruding part 11 more than the diameter 2r of the conducting body 21 stops a decent of the heating tool due to a contact with the protruding part 11 and allows starting heating at the height of the protruding part 11. Therefore, it is possible to prevent the conducting body 21 from being subjected to a load and getting crushed and to suppress an occurrence of a connection failure by making the height R of the protruding part 11 more than the diameter 2r of the conducting body 21.
It is preferable that a width W of the groove part 16 formed by at least two protruding parts 11 is equal to or less than the diameter 2r of the conducting part 21 from a standpoint of preventing a misalignment in position of the conducting body 21. The width W of the groove part 16 means a distance between two points where the conducting part 21 are in contact with the protruding parts 11 constituting the groove part 16 in the description of the present invention. Here, though the conducting part 21 comes to a state of not being in direct contact with the contacting electrode 10 when the width W is made shorter, the conducting part 21 can have an electrical continuity with the connecting electrode 10 via the protruding parts 11 even in this case. However, to joint the conducting body 21 to the connecting electrode 10 more securely, it is more preferable that the conducting part 21 is in direct contact with the connecting electrode 10.
In the cable connection structure 100 according to the first embodiment, a degree of freedom of the layout in mounting the conducting body 21 onto the board 1 can be improved by making a connection to the board 1 so that the extending direction Y of the conducting body 21 of the cable 2 is not aligned with the extending direction X of the cable 2 in the manner described above. Besides, by making the alignment pitch b of the conducting bodies 21 narrower than the alignment pitch a of the cables 2, the board 1 and the cable connection structure 100 can be made small without making the conducting part 21 thinner. Thus, it becomes possible to stably connect a lot of cables in a small area, which is suitable for a configuration of an endoscope and an ultrasound image system (ultrasound endoscope).
As a first modification of the first embodiment of the present invention, a cable connection structure 100A shown in
Besides, as a second modification of the first embodiment of the present invention, a cable connection structure in which the alignment pitch b of the conducting bodies 21 is wider than the alignment pitch a of the cables 2 is exemplified. By making the pitch b of the conducting bodies 21 wider than the alignment pitch a of the cables 2, adverse effects including crosstalk noise caused by an interference between signals transmitted in respective cables can be suppressed.
Next, a second embodiment of the present invention will be explained.
The coaxial cable 2A is provided with a center conducting body 23 as a core wire, an inner insulating body 24 provided in an outer circumference of the center conducting body 23, an outer conducting body 25 as a shielded wire which covers an outer circumference of the inner insulating body 24, and an outer insulating body 26 provided in an outer circumference of the outer conducting body 25.
The board 1A is provided with a center conducting body connecting electrode 12 (a core wire connecting electrode) to which the center conducting body 23 is connected and an outer conducting body connecting electrode 13 (a shielded wire connecting electrode) to which the outer conducting body 25 is connected. On each center conducting body connecting electrode 12, two hemispherical first protruding parts 14 are formed. A first groove part 17 in which the center conducting body 23 to connect is arranged is formed by the hemispherical first protruding parts 14 and the center conducting body connecting electrode 12.
The first protruding part 14 is formed by a gold bump or a high-melting-point solder bump. It is preferable that a height R1 of the first protruding part 14 is more than a diameter 2r1 of the center conducting body 23. By making the height R1 of the first protruding part 14 more than the diameter 2r1 of the center conducting body 23, a positional regulation of the center conducting body 23 is performed easily. In jointing the center conducting body 23 and the center conducting body connecting electrode 12 by heating a joint member such as a solder to cause fusion by a heating tool, for example, the height R1 of the first protruding part 14 more than the diameter 2r1 of the center conducting body 23 allows preventing the center conducting body 23 from being subjected to a load and getting crushed and suppressing an occurrence of a connection failure.
Besides, it is preferable that a width W1 of the first groove part 17 formed by at least two first protruding parts 14 is approximately equal to the diameter 2r1 of the center conducting body 23 from a standpoint of preventing a misalignment in position of the center conducting body 23.
On each outer conducting body connecting electrode 13, a hemispherical second protruding part 15 is formed. The second protruding part 15 is formed in line at equally-spaced intervals on the outer conducting body connecting electrode 13, the number of the second protruding part 15 being equivalent to the number obtained by adding one to the number of outer conducting bodies 25 which are connected to the board 1A along a longitudinal direction of the outer conducting body connecting electrode 13. A second groove part 18 is formed by the second protruding parts 15 arranged in line at equally-spaced intervals on the outer conducting body connecting electrode 13 and the outer conducting body connecting electrode 13, the number of the second groove part 18 being equivalent to the number of outer conducting bodies 25 to connect.
The second protruding part 15 is formed by a gold bump or a high-melting-point solder bump. It is preferable that a height R2 of the second protruding part 15 is more than a diameter 2r2 of the outer conducting body 25. By making the height R2 of the second protruding part 15 more than the diameter 2r2 of the outer conducting body 25, a positional regulation of the outer conducting body 25 is performed easily. In jointing the outer conducting body 25 and the outer conducting body connecting electrode 13 by heating a joint member such as a solder to cause fusion by a heating tool, for example, the height R2 of the second protruding part 15 more than the diameter 2r2 of the outer conducting body 25 allows preventing the outer conducting body 25 from being subjected to a load and getting crushed to prevent the inner insulating body 24 from being damaged and suppressing an occurrence of a connection failure.
Besides, it is preferable that a width W2 of the second groove part 18 formed by two second protruding parts 15 is approximately equal to the diameter 2r2 of the outer conducting body 25 from a standpoint of preventing a misalignment in position of the outer conducting body 25.
In the second embodiment, the first groove part 17 is formed so that the extending direction Y of the center conducting body 23 arranged in the first groove part 17 as shown in
In the second embodiment, the center conducting body connecting electrode 12 and the first protruding parts 14 are formed so that the alignment pitch b of the center conducting bodies 23 is narrower than the alignment pitch a of the coaxial cables 2A. The outer conducting body connecting electrode 13 and the second protruding parts 15 are formed so that an alignment pitch c of the outer conducting bodies 25 becomes the same as the alignment pitch a of the coaxial cables 2A. By arranging the outer conducting body 25 of the coaxial cable 2A in the second groove part 17, arranging, by bending the inner insulating body 24, the center conducting body 23 in the first groove part 17, supplying a joint member such as a solder to a joint part of the conducting part and the connecting electrode, and making a connection via heating the joint member to cause fusion by a heating tool on the board 1A formed in this manner, the alignment pitch b of the center conducting bodies 23 can be made narrower than the alignment pitch a of the coaxial cables 2A.
In the cable connection structure 200 according to the second embodiment, a degree of freedom of the layout in mounting the center conducting body 23 on the board 1A can be improved by making the connection to the board 1A so that the extending direction Y of the center conducting body 23 of the coaxial cable 2A is not aligned with the extending direction X of the coaxial cable 2A in the manner described above. Besides, by making the alignment pitch b of the center conducting bodies 23 narrower than the alignment pitch a of the coaxial cables 2A, a mounting density of the members to be mounted on the board 1A can be improved and the board 1A and the cable connection structure 200 can be made small. Thus, it becomes possible to stably connect a lot of coaxial cables in a small area, which is suitable for a configuration of an endoscope and an ultrasound image system (ultrasound endoscope).
As a first modification of the second embodiment of the present invention, a cable connection structure 200B shown in
As a second modification of the second embodiment of the present invention, a cable connection structure 200C shown in
As a third modification of the second embodiment of the present invention, a cable connection structure 200D shown in
As a fourth modification of the second embodiment of the present invention, a cable connection structure 200E shown in
As a fifth modification of the second embodiment of the present invention, a cable connection structure 200F shown in
A third embodiment of the present invention will be explained next. In a cable connection structure according to the third embodiment, protruding parts forming a groove part include a fixed protruding part and a fusing protruding part.
A board 1G is provided with three center conducting body connecting electrodes 12G1, 12G2, and 12G3 and an outer conducting body connecting electrode 13G. The first protruding part 14 and a first fusing protruding part 14G are formed on each of the center conducting body connecting electrodes 12G1 and 12G3. The first protruding part 14 is a fixed protruding part which is formed by a gold bump, a high-melting-point solder bump, or the like. The first fusing protruding part 14G is formed by a solder bump and the like and made of a material which fuses in soldering. In the description of the present invention, the solder bump means a bump formed by an eutectic solder of tin-lead system, melting point of which is 184 degrees C., a solder of tin-silver-copper system (of Sn-3.0Ag-0.5Cu composition, melting point of which is as high as 220 degrees C., for example) widely used as a lead-free solder, or a solder whose melting point or solidus temperature is lower than these solders. Two first fusing protruding parts 14G are formed on the center conducting body connecting electrode 12G2. The first protruding part 14 and the first fusing protruding part 14G have the same diameter.
On the outer conducting body connecting electrode 13G, the second protruding part 15 and a second fusing protruding part 15G are formed. The second protruding part 15 is a fixed protruding part which is formed by a gold bump, a high-melting-point solder bump, or the like. The second fusing protruding part 15G is a fusing protruding part formed by a solder bump and the like. In the third embodiment, inner two protruding parts are the second fusing protruding parts 15G as the fusion protrusion part and outer two protruding parts are the second protruding parts 15 as the fixed protruding part. The second protruding part 15 and the second fusing protruding part 15G have the same diameter and formed at equally-spaced intervals on the outer conducting body connecting electrode 13G.
In the third embodiment, first groove parts 17G1 to 17G3 are formed so that the extending direction Y of the center conducting bodies 23 arranged in the first groove parts 17G1 to 17G3 is not aligned with the extending direction X of the coaxial cable 2A. The first groove parts 17G1 to 17G3 are formed so that the alignment pitch b of the center conducting bodies 23 becomes wider than the alignment pitch a of the coaxial cables 2A.
In the third embodiment, since the inner insulating body 24 is bent from the extending direction X of the coaxial cable 2A and connected to the board 1G so that the alignment pitch b of the center conducting bodies 23 becomes wider than the alignment pitch a of the coaxial cable 2A, a protruding part forming a wiring route is subjected to a stress. In the third embodiment, protruding parts which are subjected to the stress are formed by the fixed protruding parts (the first protruding part 14 and the second protruding part 15) and the other protruding parts are formed by the fusing protruding parts (the first fusing protruding part 14G and the second fusing protruding part 15G), so that a misalignment in position of the coaxial cable 2A can be prevented and a process of supplying a joint member for jointing the coaxial cable 2A onto the board 1G can be eliminated.
Besides, in the cable connection structure 300 according to the third embodiment, a degree of freedom of the layout in mounting the center conducting body 23 onto the board 1G can be improved by making a connection to the board 1G so that the extending direction Y of the center conducting body 23 of the coaxial cable 2A is not aligned with the extending direction X of the coaxial cable 2A, and an adverse effect caused by an interference between signals transmitted in respective coaxial cables 2A can be suppressed since the alignment pitch b of the center conducting bodies 23 is wider than the alignment pitch a of the coaxial cables 2A.
A fourth embodiment of the present invention will be explained next. In a cable connection structure according to the fourth embodiment, protruding parts forming a groove part include the fixed protruding part and the fusing protruding part, and the fixed protruding part is formed in a size larger than the fusing protruding part.
A board 1H is provided with three center conducting body connecting electrodes 12H1, 12H2, and 12H3 and an outer conducting body connecting electrode 13H. A first protruding part 14H and the first fusing protruding part 14G are formed on each of the center conducting body connecting electrodes 12H1 to 12H3. The first protruding part 14H is a fixed protruding part which is formed by a gold bump, a high-melting-point solder bump, or the like. The first fusing protruding part 14G is a solder bump made of a material which fuses in soldering. Two first fusing protruding parts 14G are formed on the center conducting body connecting electrode 12H2. The first protruding part 14H is configured to be a bump having a larger diameter than the first fusing protruding part 14G.
On the outer conducting body connecting electrode 13H, a second protruding part 15H and the second fusing protruding part 15G are formed. The second protruding part 15H is a fixed protruding part which is formed by a gold bump, a high-melting-point solder bump, or the like. The second fusing protruding part 15G is a fusing protruding part formed by a solder bump and the like. The second protruding part 15H is configured to be a bump having a larger diameter than the second fusing protruding part 15G. In the fourth embodiment, outer two protruding parts are the second protruding parts 15H as the fixed protruding part and inner two protruding parts are the second fusing protruding parts 15G as the fusing protruding part. The second protruding part 15H and the second fusing protruding part 15G are arranged on the outer conducting body connecting electrode 13G so that the alignment pitch c of the outer conducting bodies 25 is uniform.
In the fourth embodiment, first groove parts 17H1 to 17H3 are formed so that the extending direction Y of the center conducting bodies 23 arranged in the first groove parts 17H1 to 17H3 is not aligned with the extending direction X of the coaxial cable 2A, similarly to the third embodiment. The first groove parts 17H1 to 17H3 are formed so that the alignment pitch b of the center conducting bodies 23 becomes wider than the alignment pitch a of the coaxial cables 2A.
In the fourth embodiment, since the inner insulating body 24 is bent from the extending direction X of the coaxial cable 2A and connected to the board 1H so that the alignment pitch b of the center conducting bodies 23 becomes wider than the alignment pitch a of the coaxial cables 2A, a protruding part forming a wiring route is subjected to a stress. In the fourth embodiment, protruding parts which are subjected to the stress are formed by the fixed protruding parts (the first protruding part 14H and the second protruding part 15H) and the other protruding parts are formed by the fusing protruding parts (the first fusing protruding part 14G and the second fusing protruding part 15G), and additionally the first protruding part 14H and the second protruding part 15H as the fixed protruding part are formed to be larger in diameter than the first fusing protruding part 14G and the second fusing protruding part 15G as the fusing protruding part, respectively. This configuration allows preventing a misalignment in position of the coaxial cable 2A and eliminating a process of supplying a joint member for jointing the coaxial cable 2A onto the board 1H.
Besides, in the cable connection structure 400 according to the fourth embodiment, a degree of freedom of the layout in mounting the center conducting body 23 onto the board 1H can be improved by making a connection to the board 1H so that the extending direction Y of the center conducting body 23 of the coaxial cable 2A is not aligned with the extending direction X of the coaxial cable 2A, and an adverse effect caused by an interference between signals transmitted in respective coaxial cables 2A can be suppressed since the alignment pitch b of the center conducting bodies 23 is wider than the alignment pitch a of the coaxial cables 2A.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.
Number | Date | Country | Kind |
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2011-110651 | May 2011 | JP | national |