1. Field of the Invention
The present invention relates to a connector for substrate-to-substrate connection which is used by being fixed to a substrate.
2. Description of the Related Art
As a connector which is used by being fixed to a substrate, a commonly used connector has a terminal which is soldered to the substrate and the housing which is fixed to the substrate by a screw. Japanese Unexamined Patent Application Publication No. 2008-159306 discloses a connector in which a substrate and a housing have a screw hole through which a screw is inserted to engage with the inner wall of the screw hole so as to fix the housing to the substrate. Further, there is also a compression type connector for substrate-to-substrate connection in which a substrate and a housing have a screw hole. In this case, the connector is fixed to one of the substrates, and then two substrates and the connector are fixed by one screw while the other substrate is in press contact with a terminal of the connector.
However, in a case where a screw is directly inserted into the screw hole of the housing to engage with the inner wall of the screw hole, there is a problem that a stress such as a tightening torque of the screw is directly applied to the housing and may cause deformation and damage. Further, in the above compression type connector, when a screw is too tightly tightened, the substrate may be strongly pressed against the terminal. In this case, there is a problem that a load is applied to a soldered portion of the terminal, causing a problem such as breakage and crack at the soldered portion, and the terminal may be dropped off from the substrate in the worst case.
Accordingly, it is an object of the present invention to provide a connector which can be reliably fixed to a substrate without causing an excessive stress to be applied to a housing or a terminal.
According to an aspect of the present invention, a connector includes a housing mounted on a substrate, and a terminal which is fixed to the housing so that the terminal is fixed to the substrate and is in electrically conductive contact with a connection target provided on a mating substrate which opposes the substrate, wherein the housing includes a through hole, the housing further includes a cylindrical member which is housed in the through hole and disposed between the substrate and the connection target of the mating substrate, and a tightening member which is inserted into the cylindrical member and holds the cylindrical member, the substrate and the mating substrate, and the cylindrical member includes a first protruding end which is flush with a surface of the housing or protrudes from the through hole toward the connection target of the mating substrate so that the mating substrate is not in press contact with the housing, and a second protruding end which is flush with a surface of the housing or protrudes from the through hole toward the substrate so that the substrate is not in press contact with the housing.
According to the above aspect of the invention, the housing includes a through hole, the housing further includes a cylindrical member which is housed in the through hole and disposed between the substrate and the connection target of the mating substrate. The housing further includes a tightening member which is inserted into the cylindrical member and holds the cylindrical member, the substrate and the mating substrate. Since the cylindrical member which is a separate member from the housing is housed in a through hole formed on the housing and the tightening member is inserted into the cylindrical member, the cylindrical member is disposed between the tightening member and the inner wall of the through hole. Accordingly, the tightening member can hold the substrate, the mating substrate and the housing without being stuck in the inner wall of the through hole. Therefore, direct transfer of a tightening torque of the tightening member to the housing can be prevented, thereby reducing a stress applied from the tightening member to the housing.
Further, according to the above aspect of the invention, the cylindrical member includes a first protruding end which is flush with a surface of the housing or protrudes from the through hole toward the connection target of the mating substrate so that the mating substrate is not in press contact with the housing, and a second protruding end which is flush with a surface of the housing or protrudes from the through hole toward the substrate so that the substrate is not in press contact with the housing. Accordingly, a constant distance between the substrate and the connection target can be maintained, and the mating substrate and the tightening member can be maintained not to press the housing. That is, the cylindrical member can support the connection target and the substrate in a state of being apart from the housing by a protruding amount of the protruding end from the housing, or in a state of being slightly in contact to an extent that the housing is not pressed by the connection target or the substrate. Therefore, an excessive stress applied from the substrate and the mating substrate to the housing can be prevented. Further, the cylindrical member has a high rigidity to a load applied particularly in a tubular axis direction since the cylindrical member has a tubular shape. Accordingly, even if a pressure is applied from the mating substrate to the first protruding end, and a pressure is applied from the substrate to the second protruding end, the cylindrical member is not easily deformed.
The through hole has a gap between an inner wall and the cylindrical member, and the cylindrical member can be movable in the through hole in a hole axis direction. Since the through hole has the gap, a stress from the cylindrical member to the housing can be reduced compared with a case where the cylindrical member is press fitted in the through hole and the inner wall of the through hole and the cylindrical member are in press contact with each other. Further, a tightening torque of the tightening member applied to the housing can be more effectively reduced.
The through hole has a gap between an inner wall and the cylindrical member, and the cylindrical member can be movable in the through hole in a hole axis intersecting direction. Since the through hole has the gap, a stress from the cylindrical member to the housing can be more effectively reduced compared with a case where the cylindrical member is press fitted in the through hole and is in press contact with the through hole. Further, since the gap is formed to be wider in the hole axis intersecting direction, a tightening torque of the tightening member applied to the housing can be more effectively reduced.
The cylindrical member can be made of a conductive metal and allows for electric conductive connection between the substrate and the connection target of the mating substrate. Accordingly, the cylindrical member can be used as a ground terminal. Further, since the cylindrical member is made of a conductive metal, the cylindrical member having high rigidity and resistance to deformation can be provided.
The terminal may include a plurality of branched contact pieces which are in electrically conductive contact with the connection target of the mating substrate. Accordingly, even if one of the branched contact pieces is removed from the connection target, the other of the branched contact pieces can retain electric conductive contact with the connection target, since one terminal may include a plurality of contact points with the connection target. Accordingly, the connector may have improved connection reliability.
The present invention can provide a connector which reduces a stress applied from the tightening member to the housing and has improved connection reliability by providing the cylindrical member between the through hole of the housing and the tightening member. Further, the present invention can provide a connector which reduces a stress applied to the housing or the terminal and improved connection reliability by providing the cylindrical member that maintains a distance between the substrates.
With reference to the drawings, one embodiment of a connector according to the present invention will be described. In this embodiment, a compression type connector 1 for substrate-to-substrate connection will be described as an example. Since the right side view and the left side view of the connector 1 are laterally symmetric, the left side view is omitted. Further, since the right side view and the left side view of a cylindrical member 8 are also laterally symmetric, the left side view is omitted.
In the description of the specification, claims and drawings, a width direction along the longitudinal direction of the connector 1 shown in
As shown in
As shown in
The housing 6 is made of an electrically insulating resin and is formed in a substantially cuboid shape. The housing 6 includes a terminal fixation section 6a in which a plurality of terminals 2 are arranged in parallel and a mounting section 6b having the through hole 10 for housing the cylindrical member 8.
The terminal fixation section 6a has a plurality of terminal mounting grooves 6a1 along the width direction X such that each terminal 2 is fixed to the respective terminal mounting grooves 6a1. The spring terminal 7 is disposed above the terminal fixation section 6a at a substantially center in the width direction X, and the array of terminal mounting grooves 6a1 are disposed on both sides with respect to the spring terminal 7.
The mounting section 6b is disposed on each end of the terminal fixation section 6a in the width direction X and is formed to protrude forward from the terminal fixation section 6a (in a direction opposite to a side on which the terminals 2 are mounted in the front and back direction Y). Accordingly, the connector 1 can be prevented from being fallen down forward in a state of being mounted on the substrate 5, thereby being stabilized. Moreover, the connector 1 can also be prevented from being fallen down backward in a state of being mounted on the substrate 5, thereby being stabilized, since the substrate connecting sections 2a of the terminals 2, which will be described later, are fixed to the substrate 5 by soldering on the back side (a side on which the terminals 2 are mounted in the front and back direction Y). Further, the mounting section 6b is formed to protrude downwardly from the terminal fixation section 6a in the height direction Z. The mounting section 6b has the through hole 10 at the same position as the array of the terminal mounting grooves 6a1 in the front and back direction Y, and the cylindrical member 8 is housed in the through hole 10.
The through hole 10 is formed in a substantially rectangular tubular shape and has inner walls 10a1, 10a1 which extend in the width direction X so as to face each other, an inner wall 10a2 disposed on each end side of the housing 6 in the width direction X and connected to the end of the inner walls 10a1, 10a1 and extends in the front and back direction Y, and an inner wall 10a3 disposed to face the inner wall 10a2 and connected to the end of the inner walls 10a1, 10a1 and extends in the front and back direction Y.
The inner wall 10a1 each has a housing recess 10f that houses an outward projection 8a of the cylindrical member 8, which will be described later, and an upper engagement section 10b1 that prevents the cylindrical member 8 from being dropped off.
The housing recess 10f is formed of a recess which extends from an upper end located above the distal end of the outward projection 8a when the cylindrical member 8 is housed in the through hole 10 to the lower end of the inner wall 10a1. Further, a length of the housing recess 10f in the width direction X is substantially the same as that of the outward projection 8a.
The upper engagement section 10b1 is formed on the inner wall 10a1 at a position above the housing recess 10f and on the side of the through hole 10 on which an upper opening 10c1 is located. Further, since the upper engagement sections 10b1, 10b1 are formed protruding toward each other from the inner walls 10a1, 10a1 into the inside of the through hole 10, the upper opening 10c1 of the through hole 10 has a small dimension in the front and back direction Y than the inner dimension of the through hole 10. Even if the cylindrical member 8 is upwardly displaced from the through hole 10 (toward the mating substrate 4), the outward projection 8a of the cylindrical member 8 can engage with the upper engagement section 10b1 to prevent the cylindrical member 8 from being dropped off.
The inner wall 10a2 has a lower engagement section 10b2 that prevents the cylindrical member 8 from being dropped off. The lower engagement section 10b2 is formed on the inner wall 10a2, which is disposed between the inner walls 10a1, 10a1 on each end side of the housing 6 in the width direction X, on the side of the through hole 10 on which a lower opening 10c2 is located and protrudes into the inside of the through hole 10. The lower engagement section 10b2 can engage with a recess 8b of the cylindrical member 8, which will be described later, to prevent the cylindrical member 8 from being dropped off downwardly (toward the substrate 5) from the through hole 10.
The cylindrical member 8 is formed by bending a metal sheet into a substantially rectangular tubular shape. Further, as shown in
As shown in
The walls 8c1, 8c1 are disposed so as to face each other and have outward projections 8a, 8a, respectively, which protrude on the outside of the cylindrical member 8 toward the inner walls 10a1, 10a1 of the through hole 10 in a state of being housed in the through hole 10. Accordingly, two outward projections 8a are disposed so as to protrude in a direction apart from each other. The outward projection 8a is provided as an elastic piece in a cantilever shape which extends from an end on a side of the second protruding end 8d2 toward an end on a side of the first protruding end 8d1 in the height direction Z since it is cut and raised from the walls 8c1, 8c1 of the cylindrical member 8. When a force is applied to the cylindrical member 8 to move it upward in a state of being housed in the through hole 10, the upper ends of the outward projections 8a, 8a engage with the upper engagement sections 10b1, 10b1 of the through hole 10 as described above, thereby preventing the cylindrical member 8 from being dropped off from the upper side of the through hole 10.
The recess 8b is disposed on a lower part of the wall 6b2, and the recess 8b has an engagement end 8b1 which is an end face which extends in the width direction X and is oriented downward. The engagement end 8b1 engages with the upper end of the lower engagement section 10b2 on the inner wall 10a2 of the through hole 10 when the cylindrical member 8 is housed in the through hole 10 of the housing 6, thereby preventing the cylindrical member 8 from being dropped off from the lower side of the through hole 10.
The wall pieces 8c3, 8c3 are each connected to the ends of the walls 8c1, 8c1 and extend in the front and back direction Y. Since a slit 8e is formed between the wall pieces 8c3, 8c3, the cylindrical member 8 is open at the slit 8e and is not closed.
Since the cylindrical member 8 is made of a conductive metal and allows for electrically conductive contact between the substrate 5 and the connecting section 4a of the mating substrate 4, the cylindrical member 8 can be used as a ground terminal. Accordingly, there is no need of providing an additional member, and the ground terminal can be provided without increasing the number of components.
As shown in
The fixation section 7a includes a plate surface that extends along a side wall 6c of the housing 6 and engagement sections (not shown in the figure) on both ends in the width direction X. When the engagement section is press fitted into an engagement receiving section (not shown in the figure) of the housing 6, the spring terminal 7 is fixed to the housing 6.
The movable section 7b is disposed to extend upward from the fixation section 7a and has two movable pieces 7b1 having a shaft narrower than that of the fixation section 7a. These movable pieces 7b1 of a narrower shaft facilitate elastic deformation when a force is applied from the mating substrate 4.
The bending section 7c is connected to the distal end of the movable section 7b and is bent toward the front side of the housing 6. When the lower surface of the bending section 7c holds the top surface of the mating substrate 4, the mating substrate 4 can be temporarily fixed to the connector 1.
The terminal 2 is formed by bending a metal sheet. As shown in
The plate surface of the substrate connecting section 2a is in contact with the substrate 5 and is fixed to the substrate by soldering. The substrate connecting section 2a is formed to slightly protrude downward from the mounting section 6b of the housing 6 in the height direction Z (toward the substrate 5 in the height direction Z). Accordingly, when the terminals 2 are fixed to the substrate 5, the mounting section 6b is held in a state of being lifted above the substrate 5 by a protruding length.
The fixation section 2b is connected to the substrate connecting section 2a and extends in the front and back direction Y. Further, the fixation section 2b has protrusions 2b1 at both ends in the width direction X. When the protrusions 2b1 mesh with the inside of the terminal mounting grooves 6a1 of the housing 6, the entire terminal 2 is fixed to the housing 6.
The movable section 2c has a first bending section 2c1, an extending section 2c2 and a second bending section 2c3. The first bending section 2c1 is bent backward in the front and back direction Y from the end of the fixation section 2b and is formed in a U-shape. The extending section 2c2 extends from the first bending section 2c1 in the front and back direction Y and is connected to the second bending section 2c3. The second bending section 2c3 is bent forward in the front and back direction Y and is formed in a U-shape. The end of the second bending section 2c3 is connected to the contact section 2d.
The contact section 2d has two branched contact sections 2d1, and the branched contact sections 2d1, 2d1 are each in electrically conductive contact with the connecting section 4a of the mating substrate 4. The branched contact sections 2d1, 2d1 can be independently elastically deformed. Even if one of the branched contact sections 2d1 is removed from the connecting section 4a of the mating substrate 4, the other of the branched contact sections 2d1 can retain electric conductive contact with the connecting section 4a since the terminal 2 has a plurality of branched contact sections 2d1. Accordingly, the terminal 2 may have improved connection reliability.
The second protruding end 8d2 of the cylindrical member 8 is inserted into the upper opening 10c1 of the through hole 10. The outward projection 8a is formed in a cantilever shape which extends from a side of the second protruding end 8d2 to a side of the first protruding end 8d1 in the height direction Z and from inside to outside of the cylindrical member 8 in the front and back direction Y. Accordingly, when the cylindrical member 8 is inserted into the through hole 10, the outward projection 8a comes into contact with the upper engagement section 10b1 of the through hole 10. Since the outward projection 8a is formed as an elastic piece, it is pressed by the upper engagement section 10b1 of the through hole 10 and can be elastically deformed toward inside of the cylindrical member 8. Then, when the cylindrical member 8 is inserted deeper (downward) in the through hole 10 and the outward projection 8a passes by the upper engagement section 10b1 of the through hole 10, the outward projection 8a returns to the original shape by its elasticity (see
Further, although the cylindrical member 8 is formed in a substantially rectangular tubular shape, the slit 8e is disposed between the wall pieces 8c3, 8c3 as described above and the cylindrical member 8 is not completely closed. Accordingly, when the cylindrical member 8 is inserted into the above-described narrow area between the upper engagement sections 10b1, 10b1, the wall pieces 8c3, 8c3 can be elastically deformed so that their ends are brought close to each other to close the slit 8e. Since the length of the cylindrical member 8 in the front and back direction Y can be smaller than that of the original shape, the cylindrical member 8 can easily pass through the narrow upper opening 10c1 of the through hole 10.
Since the engagement end 8b1 of the recess 8b is placed on the lower engagement section 10b2 of the through hole 10 due to the weight of the cylindrical member 8 inserted into the through hole 10, the cylindrical member 8 is prevented from being dropped off from the lower side of the through hole 10 (see
Since the outer shape of the cylindrical member 8 is formed to be smaller than a space 10d formed by the inner walls 10a1 to 10a3 of the through hole 10, a gap 10e is provided between the cylindrical member 8 and the through hole 10 (see
Further, a distance L2 (see
As shown in
As shown in
As described above, since the cylindrical member 8 which is a separate member from the housing 6 is disposed between the screw 9 and the through hole 10, the substrate 5, the mating substrate 4 and the housing 6 can be fixed while preventing the screw 9 from being stuck in the inner walls 10a1 to 10a3 of the through hole 10. Accordingly, direct transfer of a tightening torque of the screw 9 to the housing 6 can be prevented, thereby reducing a stress applied from the screw 9 to the housing 6. Further, since the through hole 10 has the gap 10e between the cylindrical member 8 and the through hole 10, transfer of a tightening torque of the screw 9 to the housing 6 can be more effectively prevented.
As shown in
As described above, the cylindrical member 8, which is provided between the substrate 5 and the connecting section 4a of the mating substrate 4, serves as a support member that maintains an interval between two substrates 4, 5. Accordingly, a constant distance between the substrate 5 and the connecting section 4a of the mating substrate 4 can be maintained, and the mating substrate 4 and the substrate 5 can be maintained not to press the housing 6. That is, the cylindrical member 8 can support the connecting section 4a in a state of being apart from the housing 6 by a protruding amount of the first protruding end 8d1 protruding from the top surface of the housing 6, or in a state of being slightly in contact with the connecting section 4a to an extent that the housing 6 is not pressed. Further, the cylindrical member 8 can support the substrate 5 in a state of being apart from the housing 6 by a protruding amount of the second protruding end 8d2 protruding from the lower surface of the housing 6 or in a state of being slightly in contact with the substrate 5 to an extent that the housing 6 is not pressed.
Further, the cylindrical member 8 has a high rigidity to a load applied in a tubular axis direction since the cylindrical member 8 has a tubular shape. Accordingly, even if a pressure is applied from the mating substrate 4 to the first protruding end 8d1, or a pressure is applied from the substrate 5 to the second protruding end 8d2, the cylindrical member 8 is not easily deformed. Further, since the cylindrical member 8 is formed by a metal sheet, the cylindrical member 8 having high rigidity and resistance to deformation can be provided.
As described above, according to the connector 1 of the present embodiment, since the cylindrical member 8 is inserted into the through hole 10 and then the screw 9 is inserted into the cylindrical member 8, the mating substrate 4, the substrate 5 and the cylindrical member 8 can be held while preventing the screw 9 from being stuck in the inner walls 10a1 to 10a3 of the through hole 10. Accordingly, a stress to the housing 6 caused by the stuck screw 9 can be reduced. Further, since the first protruding end 8d1 of the cylindrical member 8 protrudes from the through hole 10 toward the mating substrate 4, a stress applied from the mating substrate 4 to the housing 6 can be reduced. Similarly, since the second protruding end 8d2 protrudes from the through hole 10 toward the substrate 5, a stress applied from the substrate 5 to the housing 6 can be reduced. Further, since the through hole 10 has the gap 10e between the cylindrical member 8 and the through hole 10 so as to allow the cylindrical member 8 to move, a stress applied from the cylindrical member 8 to the housing 6 can be reduced.
In the above embodiment, an example has been described in which the connector 1 has the first protruding end 8d1 and the second protruding end 8d2 protruding from the through hole 10. However, one or both of the first protruding end 8d1 and the second protruding end 8d2 may be provided flush with a surface of the housing 6 (a top surface 6b1 or a lower surface 6b2 of the mounting section 6b). In this configuration, since the housing 6 can be slightly in contact with the substrate 5 or the mating substrate 4 to an extent of not being pressed, a stress applied to the housing 6 can be reduced. However, in this case, the lower end of the substrate connecting section 2a of the terminal 2 needs to be in the same height position as that of the housing 6 in the height direction Z. Accordingly, the lower end of the substrate connecting section 2a is prevented from protruding downward from the housing 6 and a stress is not applied from the substrate 5.
In the above embodiment, the connector 1 includes the through hole 10 formed in a substantially rectangular tubular shape and the cylindrical member 8 formed in a substantially rectangular tubular shape. However, the through hole 10 and the cylindrical member 8 can be formed in a substantially cylindrical shape in accordance with the cross sectional shape of the screw 9. In this case, the outer shape of the cylindrical member 8 is formed to be smaller than the through hole 10 so that the gap 10e is formed, thereby reducing a stress applied from the cylindrical member 8 and the screw 9 to the housing 6.
Number | Date | Country | Kind |
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2014-141274 | Jul 2014 | JP | national |