The present invention relates to a connection member that connects boards.
Conventionally, leads or flexible printed circuits (FPCs: Flexible Printed Circuits) are used as connection members to connect boards such as circuit boards and the wiring on boards. These connection members are flexible and deformable, therefore, they are used for connections between movable parts. Especially, an FPC has a structure in which a circuit formed from a metal foil is sandwiched between insulating films and has a thickness as thin as tens of pm (micrometers), therefore, it is bendable, so that an FPC can be used even in a narrow space.
The above-described connection member is fixed to each board with solder or the like to connect boards. Current can be reliably caused to flow even when a movable member is moved by joining the boards to the connection member with solder or the like, therefore, it is important to correctly fix the connection member to the boards. Thus, as a method of securely attaching solder while preventing leakage of the solder from a joint, a method of forming grooves on the solder joint on boards and crimping the connection member is disclosed (for example, see Patent Literature 1).
Patent Literature 1: Japanese Patent Application Laid-open 2007-258410
However, even with the method disclosed in Patent Literature 1, there is a problem in that a load is placed on a crimped portion of solder or the like due to the transmission of vibrations of the movable member to the connection member, such as an FPC, therefore, solder or the like is stripped or damaged and the connection member and the boards becomes disconnected from each other, thereby interrupting current flow between the boards. Especially, because an FPC is bendable but not stretchable, solder or the like is stripped and damaged in some cases at a joint due to a force applied in a stretching direction or a force due to torsion.
The present invention is achieved in view of the above and has an object to provide a connection member capable of preventing stripping and damage of solder or the like at a joint due to vibrations with a board.
To solve the problem described above and achieve the object, a connection member that connects different boards, comprises: a plurality of conductive elastic members each of which includes two contact portions that are in contact with the different boards at ends, respectively, and an elastic portion that is provided between the two contact portions and is stretchable according to a force applied from outside the connection member; and an insulating restraining member that restrains movement of each of the elastic members by holding part of each of the elastic members.
In the connection member according to the present invention as set forth in the invention described above, a plurality of groove portions, which extend in directions parallel to each other and each of which holds at least the elastic portion, is formed on the restraining member.
In the connection member according to the present invention as set forth in the invention described above, the groove portion includes an approximately columnar accommodation hole that accommodates and holds part of the elastic member, and an approximately columnar opening that communicates with the accommodation hole and has a diameter smaller than a diameter of the accommodation hole.
In the connection member according to the present invention as set forth in the invention described above, the groove portions are formed on one side of the restraining member.
In the connection member according to the present invention as set forth in the invention described above, the restraining member further includes a lid that covers the groove portions.
In the connection member according to the present invention as set forth in the invention described above, the restraining member has a rectangular parallelepiped shape, and includes a plurality of approximately cylindrical holes that have a cross-sectional shape, through which the elastic portion is capable of being inserted, and extend through opposite side surfaces of the rectangular parallelepiped shape.
In the connection member according to the present invention as set forth in the invention described above, the elastic member is formed of a wire rod, the elastic portions each have a zigzag shape repeating S shape, formation surfaces of the zigzag shape are parallel to each other, and a width in a direction in which the zigzag shape of the elastic portion reciprocates is larger than an interval between adjacent elastic members.
In the connection member according to the present invention as set forth in the invention described above, the contact portions are parallel to each other and pass a same plane, and the plane is perpendicular to the formation surfaces of the zigzag shape.
The connection member according to the present invention is such that part of a conductive wire connecting boards is formed of an elastic member to reduce a load due to vibrations applied to a joint of the boards and the connection member, therefore, when the boards vibrate, the force due to vibrations is attenuated by the elastic member and the force applied to the joint of the boards and the connection member is suppressed, so that an effect is obtained in that stripping and damage of solder or the like at the joint due to vibrations can be prevented and current flow between the boards can be stabilized.
Embodiments of the present invention will be explained below in detail with reference to the drawings. The present invention is not limited to the following embodiments. Each drawing referred to in the following explanation only schematically illustrates the shape, the size, and the positional relationship to be able to understand the content of the present invention and therefore, the present invention is not limited to only the shape, the size, and the positional relationship illustrated in each drawing.
The configuration and the operation of a connection member 1 according to a first embodiment of the present invention will be explained below with reference to the drawings.
As shown in
As shown in
The restraining member 12 has a rectangular parallelepiped shape formed by using an insulating material such as resin and includes a holding unit 121 that holds the elastic members 11 and a lid 122 that is locked to the holding unit 121 in a state of covering the upper portion of the holding unit 121. Moreover, the holding unit 121 includes a plurality of groove portions 121a, which are formed on one side of the rectangular parallelepiped, which extend in directions parallel to each other, and each of which holds the elastic member 11, and includes a plurality of recess portions 121b, which are formed on the sides on which groove portions 121a do not pass and which are perpendicular to the side on which the groove portions 121a are formed, and into which part of the lid 122 can be fit.
The groove portion 121a includes a first groove portion 121c and two second groove portions 121d extending from both ends of the first groove portion 121c. The first groove portion 121c can accommodate the elastic portion 111, has a length slightly larger than a natural length of the elastic portion 111 in a longitudinal direction, and has a length (width) slightly larger than the width of the elastic portion 111 in a lateral direction. Moreover, the second groove portion 121d can accommodate part of the contact portion 112 and has a central axis aligned with the central axis of the first groove portion 121c. In
The lid 122 includes a covering portion 122a covering the holding unit 121 and claw portions 122b that project in a direction perpendicular to the covering surface from the outer edge of the covering portion 122a and can fit into the recess portions 121b of the holding unit 121. The tip of the claw portion 122b is bent with respect to the direction in which the claw portion 122b extends and is locked to the surface, which is opposed to the surface on which the groove portions 121a are formed among the surfaces of the lid 122, when the lid 122 is attached to the holding unit 121.
The operation of the elastic member 1 when the boards P1 and P2 vibrate will be explained with reference to
Thereafter, as shown in
In
According to the above-described first embodiment, when the boards vibrate, the elastic portions of the connection member extend and compress to relax the force applied to the solders in a direction opposite to the moving direction of the boards, so that stripping or damage of the solders, which fix connection between the connection member and the electrodes, can be prevented. Moreover, because each groove portion formed on the restraining member holds the elastic member, the elastic members do not come into contact with each other, so that current can flow reliably to a corresponding electrode on the board.
In the first embodiment, a plurality of groove portions is provided on one side of the holding unit, however, the groove portions may be provided on a plurality of sides of the holding unit in a distributed fashion. The elastic members may be coated with insulating resin such as enamel. The elastic members can be insulated more securely by coating them with insulating resin.
Next, the configuration of a connection member 2 according to a second embodiment of the present invention will be explained with reference to the drawings.
As shown in
The elastic member 21 includes an elastic portion 211 having a zigzag shape in which shapes of the letter S are consecutive and two contact portions 212 that linearly extend along a plane (hereinafter, “zigzag surface”) including the entire portion in which the elastic portion 211 extends in a zigzag shape. The elastic portion 211 is formed into a flat shape having a thickness equal to the diameter of a wire rod.
The holding unit 221 includes a plurality of groove portions 221a, each of which accommodates and holds the elastic portion 211 and part of the contact portion 212 and which extend in directions parallel to each other, and includes a plurality of recess portions 221b, which are formed on the sides on which groove portions 221a do not pass and which are perpendicular to the side on which the groove portions 221a are formed, and into which part of the lid 222 can be fit. The groove portion 221a includes a first groove portion 221c and second groove portions 221d. Because the groove portions 221a each accommodate the elastic member 21, the elastic members 21 do not come into contact with each other. The bottom surface of the first groove portion 221c is formed to correspond to the zigzag surface of the elastic portion 211. The length of the first groove portion 221c in the longitudinal direction is larger than the natural length of the elastic portion 211. Moreover, the depth of the first groove portion 221c and the second groove portion 221d is slightly larger than the diameter of a wire rod.
The lid 222 includes a covering portion 222a covering the holding unit 221 and claw portions 222b that project in a direction perpendicular to the covering surface from the outer edge of the covering portion 222a and can fit into the recess portions 221b of the holding unit 221. The tip of the claw portion 222b is bent with respect to the direction in which the claw portion 222b extends and is locked to the surface, which is opposed to the surface on which the groove portions 221a are formed among the surfaces of the lid 222, when the lid 222 is attached to the holding unit 221.
The connection member according to the above-described second embodiment can be formed into a flat shape having a thickness of about a wire rod in a direction perpendicular to the zigzag surface, so that the restraining member can be formed thinner. Moreover, in the similar manner to the first embodiment, because the force applied to the solders can be relaxed by the elastic portions regardless of the vibration direction of the boards, a stable conduction state can be maintained even when the boards vibrate.
Next, the configuration of a connection member 3 according to a third embodiment of the present invention will be explained with reference to the drawings.
The connection member 3 shown in
As shown in
The connection member in the third embodiment can be configured only with the holding unit as a restraining member by changing the configuration of the groove portions.
The connection member 3a shown in
When connecting the connection member 3a having the above configuration with the boards P3 and P4 shown in
The connection member 3a is formed by inserting the elastic members 31 into the accommodation holes 223b from the side surface of the holding unit 223. At this time, the curved portion 312a formed vertically with respect to the holding unit 223 passes through the opening 223c, so that the connection member 3a can be formed by inserting the elastic members 31 into the holding unit 223 while not being retarded by the curved portions 312a.
Moreover, in the similar manner to the connection member 3 shown in
The connection member according to the above-described third embodiment can further relax the vibrations transmitted from the boards by providing the curved portions to the contact portions and facilitate connection between the contact members and the boards by the curved portions functioning as positioning pins. Especially, the third embodiment is effective when the elastic members have a relatively low stretchability, for example, when the diameter of the elastic members is 0.2 mm or more.
Next, the configuration of a connection member according to a fourth embodiment of the present invention will be explained with reference to the drawings.
The connection member 4 shown in
The elastic member 41 is formed of a wire rod and includes an elastic portion 411 stretchable (in an arrow direction in
The restraining member 42 has a columnar shape and includes a plurality of approximately cylindrical holes extending through the opposite side surfaces of this column. The holes are provided to correspond to the elastic members 41 and cause part of each elastic member 41 to be inserted therethrough. Moreover, the holes have a cylindrical shape having a diameter approximately equal to that of the elastic member 41 and are arranged such that the central axes of the holes are parallel to each other. Consequently, the restraining members 42 hold the elastic members 41 in a state where the zigzag surfaces of the elastic members 41 are parallel to each other.
According to the connection member 4 having the above configuration, even when the elastic member 41 moves toward the adjacent elastic member 41, the elastic members 41 do not come into contact with each other, so that current can be made to flow stably. Moreover, in the connection member 4, because the width L (see
The connection member according to the above-described fourth embodiment prevents the elastic members from coming into contact with each other by a plurality of the restraining members holding the elastic members to be parallel to each other and relaxes the vibrations from the boards by extension and compression of the elastic portions, and therefore can make current to flow stably and prevent stripping and damage of the solders. Moreover, each elastic member is arranged such that the zigzag surface of the elastic portion is perpendicular to the plane on which the contact portions is arrayed and the zigzag surfaces of the elastic portions are parallel to each other, enabling to be torsionally rigid and further relax the force in response to vibrations in any direction.
The arrangement of the restraining members 42 may be such that the contact portions 412 are inserted through the restraining members 42 and the restraining members 42 may be arranged at different heights from each other. The arrangement of the restraining members may be one other than the above so long as the elastic members 41 are held parallel to each other by the restraining members 42 and the elastic members 41 do not come into contact with each other, and, for example, the restraining members 42 may be arranged at a portion at which the elastic members are bent. Moreover, the contact portion 412 may have a curved portion having a shape similar to the curved portion 312a shown in
Next, the configuration of a connection member according to a fifth embodiment of the present invention will be explained with reference to
The connection member 5 shown in
The connection member according to the above-described fifth embodiment can be formed into a flat shape having a thickness of about the diameter of a wire rod in a direction perpendicular to the zigzag surface, so that the restraining member can be formed thinner, and moreover, the elastic members can be held in the restraining member with a simple configuration and the force applied to the solders can be relaxed regardless of the vibration direction of the boards, so that a stable conduction state can be maintained.
After accommodating the elastic members 21 in the accommodation holes 224a, the accommodation holes 224a may be sealed with a cap or the like. The elastic members 21 can be prevented from dropping from the holding unit 224 by sealing the accommodation holes 224a.
Moreover, when the elastic portion has a coil shape of a circular cross section as shown in
Next, a connection member according to a sixth embodiment will be explained with reference to
The connection member according to the above-described sixth embodiment prevents the elastic members from coming into contact with each other by a plurality of the restraining members holding the elastic members to be parallel to each other and relaxes the vibrations from the boards by extension and compression of the elastic portions, and therefore can make current to flow stably and prevent stripping and damage of the solders. The elastic portions may be coated with insulating resin such as enamel.
The winding directions of the elastic portions 631 shown in
Next, the configuration of a connection member according to another embodiment of the present invention will be explained with reference to the drawings.
The connection member 7 shown in
The tilt of the tilt portion 711a changes due to the vibrations of the boards connected to the ends of the connection portions 712, so that the connection member 7 relaxes the force applied to the solders.
The connection member according to the above-described another embodiment is composed of the stretchable elastic members and the restraining members that prevent the elastic members from coming into contact with each other, and can attenuate the vibrations of the boards with a simple structure and thus relax the force applied to the solders.
Moreover,
The end shape of the contact portion can be deformed according to the boards to be connected. Especially, the end of the contact portion 712 and the end of the elastic member 81 are preferably formed in parallel with or vertical to the boards for connection with the boards.
The connection members according to the first to sixth embodiments and other embodiments described above can adjust the length of the elastic member (the elastic portion and/or the contact portion) according to the distance between the members (between the boards) that are the connection targets. Moreover, the configuration of the restraining member can be changed according to the length of the elastic member.
The present invention is not limited to the configurations illustrated in the above-described embodiments and can be variously modified without departing from the gist thereof.
A connection member that connects different boards, comprising:
a plurality of conductive elastic members each of which includes two contact portions that are in contact with the different boards at ends, respectively, and an elastic portion that is provided between the two contact portions and is stretchable according to a force applied from outside the connection member; and
an insulating restraining member that restrains movement of each of the elastic members by holding part of each of the elastic members.
The connection member according to note 1, wherein a plurality of groove portions, which extend in directions parallel to each other and each of which holds at least the elastic portion, is formed on the restraining member.
The connection member according to note 2, wherein
the groove portion includes
The connection member according to note 2 or 3, wherein the groove portions are formed on one side of the restraining member.
The connection member according to any one of notes 2 to 4, wherein the restraining member further includes a lid that covers the groove portions.
The connection member according to note 1, wherein the restraining member has a rectangular parallelepiped shape, and includes a plurality of approximately cylindrical holes that have a cross-sectional shape, through which the elastic portion is capable of being inserted, and extend through opposite side surfaces of the rectangular parallelepiped shape.
The connection member according to any one of notes 1 to 6, wherein the elastic portion has a coil shape.
The connection member according to any one of notes 1 to 6, wherein the elastic portion has a zigzag shape repeating S shape.
The connection member according to note 1, wherein the elastic member is formed of a wire rod, and the restraining member includes a plurality of holes which have a diameter approximately equal to a diameter of the wire rod and through which part of the elastic member is inserted.
The connection member according to note 9, wherein the restraining member is such that planes that pass central axes of the holes are approximately parallel to each other.
The connection member according to note 9 or 10, wherein the elastic portion has a zigzag shape repeating S shape.
The connection member according to note 11, wherein
the elastic portions are such that formation surfaces of the zigzag shape are parallel to each other, and
a width in a direction in which the zigzag shape of the elastic portion reciprocates is larger than an interval between adjacent elastic members.
The connection member according to note 12, wherein
the contact portions are parallel to each other and pass a same plane, and
the plane is perpendicular to the formation surfaces of the zigzag shape.
The connection member according to note 9 or 10, wherein the elastic portion has a coil shape.
The connection member according to any one of notes 1 or 14, wherein the contact portion includes a convexly curved curved portion.
As above, the connection member according to the present invention is useful, for example, when connecting members that vibrate and is especially suitable for connecting boards to cause current to flow between the boards.
1, 2, 3, 3a, 4, 5, 6, 6a, 7, 8 CONNECTION MEMBER
11, 21, 31, 41, 61, 63, 71, 81 ELASTIC MEMBER
12, 22, 42, 62, 72, 82 RESTRAINING MEMBER
111, 211, 311, 411, 611, 631, 711 ELASTIC PORTION
112, 212, 312, 412, 612, 632, 712 CONTACT PORTION
121, 221, 223, 224 HOLDING UNIT
121
a,
221
a,
223
a GROOVE PORTION
121
b,
221
b RECESS PORTION
122, 222 LID
122
a,
222
a COVERING PORTION
122
b,
222
b CLAW PORTION
223
b,
224
a ACCOMMODATION HOLE
223
c OPENING
312
a CURVED PORTION
711
a TILT PORTION
C1, C2 HOLE
E1 to E4 ELECTRODE
P1 to P4 BOARD
S1 to S4 SOLDER
Number | Date | Country | Kind |
---|---|---|---|
2009-266845 | Nov 2009 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/JP2010/070888 | 11/24/2010 | WO | 00 | 5/24/2012 |