JP2004151636A - Optical connector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To securely solder an electrode part of an optical element to a wiring pattern of a wiring board in an optical connector equipped with a surface-mounted optical element. <P>SOLUTION: A 1st housing is equipped with a 1st housing body part 12 where an element storage recessed part 13 for storing and holding the optical element 40 is formed, a guide sleeve part 14 which guides an optical fiber toward the optical element in the element storage recessed part 13, and a fitting lock part 16 which can be fitted and fixed to the wiring board. At the 1st housing body part 12, an elastic energizing piece 18 is formed to energize the optical element 40 toward a main surface of the wiring board. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical connector used in the field of optical communication such as OA, FA and in-vehicle equipment, and more particularly to an optical connector used when connecting an optical element and an optical fiber.
[0002]
[Prior art]
2. Description of the Related Art As a conventional optical connector, there is a connector mounted on a wiring board in a state in which an optical element is housed (for example, see Patent Document 1). To this optical connector, a mating optical connector holding the optical fiber is connected, and thereby the optical fiber and the optical element are optically coupled.
[0003]
In such a conventional optical connector, an optical element with a lead terminal is housed and held in a connector housing, and the optical element is electrically connected to a wiring pattern of a wiring board via the lead terminal.
[0004]
[Patent Document 1]
JP 2001-296455 A
[Problems to be solved by the invention]
Incidentally, there is a relatively small surface mount type optical element. When this is applied to the optical connector as described above, a configuration in which a surface-mount type optical element is housed and held at a position where it can be surface-mounted on a wiring board can be considered.
[0006]
However, in this case, if the bottom surface of the connector housing and the bottom surface of the optical element do not exactly coincide with each other, the electrode portion of the optical element is connected to the wiring board with the bottom surface of the connector housing closely arranged on the wiring board. May not be able to be soldered well to the wiring pattern.
[0007]
SUMMARY OF THE INVENTION It is an object of the present invention to provide an optical connector having an optical element of a surface mounting type, in which an electrode portion of the optical element can be securely soldered to a wiring pattern of a wiring board.
[0008]
[Means for Solving the Problems]
In order to solve the above problem, the invention according to claim 1 is an optical connector mounted on a main surface of a wiring board in a state in which an optical element is housed, wherein an electrode portion is formed on a surface of an element body. A surface mounting type optical element, a housing body having an element receiving recess for receiving and holding the optical element in a state capable of being surface mounted on the wiring board, and an optical fiber optically coupled to the optical element. A guide sleeve portion for guiding as much as possible, and a mounting portion for mounting and fixing the housing main body to the wiring board in a state where the bottom of the housing main body is disposed in close contact with the main surface of the wiring board. A first housing having an element urging portion for urging the optical element toward the main surface of the wiring board.
[0009]
As described in claim 2, the mounting portion is inserted into an engaging hole formed on the wiring board side from the main surface side of the wiring board so as to engage with the engaging hole in a retaining shape. It may be a fitting lock portion that can be combined.
[0010]
As described in claim 3, the element urging portion may be a tongue-shaped elastic urging piece formed by forming a substantially U-shaped slit in a ceiling portion of the housing body. .
[0011]
As described in claim 4, the optical fiber is attached and fixed to the wiring board so as to cover the first housing, and the housing of the mating optical connector holding the optical fiber is fitted and connected, thereby connecting the optical fiber. The electronic device may further include a second housing that guides toward the guide sleeve portion.
[0012]
In this case, as described in claim 5, the second housing may have a lock portion that can be locked to the other optical connector side.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an optical connector according to an embodiment of the present invention will be described.
[0014]
1 is an exploded perspective view showing the optical connector 10, FIG. 2 is a sectional view showing the optical connector 10, and FIG. 3 is a perspective view showing a state where the optical connector 10 is mounted and fixed on a wiring board 70.
[0015]
The optical connector 10 is of a type that is mounted and fixed to a wiring board 70 in a state where the optical element 40 is housed. The mating optical connector 50 holding the optical fiber 61 is fitted and connected to the optical connector 10 mounted and fixed on the wiring board 70 (see FIG. 2).
[0016]
The optical connector 10 includes an optical element 40, a first housing 11, and a second housing 20.
[0017]
The optical element 40 is a light receiving element (such as a photodiode or a phototransistor) that converts an optical signal into an electric signal or a light emitting element (such as a light emitting diode) that converts an electric signal into an optical signal. As the optical element 40, a surface mount type is used, that is, the optical element 40 has a configuration in which an electrode section 40b is formed on an element main body section 40a. More specifically, the optical element 40 has a substantially L-shaped strip-shaped electrode section 40b extending from the lower rear surface of the element body section 40a to the bottom surface thereof (see FIG. 2). In the present embodiment, the optical connector 10 includes two optical elements 40.
[0018]
It should be noted that such a surface-mount type optical element 40 has an advantage that it can be easily mounted on the wiring board 70 as compared with an optical element with lead terminals which has been generally used conventionally.
[0019]
FIG. 4 is a cross-sectional view of the first housing 11, and FIG. 5 is a cross-sectional view showing a state where the optical element is accommodated and arranged in the first housing 11.
[0020]
As shown in FIGS. 1 to 5, the first housing 11 includes a first housing body 12, a guide sleeve 14, an attachment lock 16 as an attachment, and an elastic urging piece as an element urging unit. 18 is provided.
[0021]
In a state where the first housing 11 is disposed on the wiring board 70 as described later, the optical element 40 is surface-mounted on the wiring board 70 by reflow soldering or the like. In order to prevent the first housing 11 from being damaged, it is preferable that the first housing 11 is formed using a material which does not melt at a processing temperature at that time, that is, at a soldering temperature. In order to efficiently release the heat generated in the optical element 40 to the outside, the first housing 11 is made of a material having a higher thermal conductivity, here, a material having a higher thermal conductivity than the second housing 20. Preferably, it is formed. Materials satisfying both of these include metal materials such as copper and copper alloys.
[0022]
The first housing main body 12 is formed in a substantially rectangular parallelepiped housing whose bottom side is open, and an element accommodating recess 13 is formed therein.
[0023]
The element accommodating recess 13 is formed so as to be capable of accommodating and holding the optical element 40 on the upper surface side, which is one main surface of the wiring board 70, in a state capable of being surface-mounted. That is, the element accommodating recess 13 has an inner shape that is substantially the same as the outer shape of the optical element 40. The bottom side of the back surface of the first housing body 12 is open. When the optical element 40 is accommodated in the element accommodating recess 13, the electrode portion 40 b of the optical element 40 is disposed so as to be exposed through the bottom opening of the first housing main body 12 and the rear bottom opening. Then, in a state where the first housing main body portion 12 is closely arranged on the wiring board 70, the electrode portion 40b is brought into contact with or close to a predetermined wiring pattern 72 formed on the upper surface side of the wiring board 70. You.
[0024]
Further, a guide sleeve portion 14 is arranged to protrude from the front side of the first housing body portion 12. The guide sleeve portion 14 is formed in a substantially cylindrical shape into which the ferrule portion 55 of the mating optical connector 50 can be inserted and which has a hole communicating with each of the element accommodating recesses 13. Then, when the optical connector 10 and the optical connector 50 are connected, each ferrule portion 55 is inserted into each corresponding guide sleeve portion 14 and guided toward the optical element 40 in each element accommodating recess 13. Then, in a state where each ferrule portion 55 is completely inserted into each guide sleeve portion 14, the end face of each optical fiber 61 exposed at the tip end of each ferrule portion 55 is on the light emitting surface or light receiving surface of each optical element 40. They are arranged to face each other and optically coupled to each other.
[0025]
In the present embodiment, the two housing main bodies 12 are connected to each other at the bottom thereof, and the optical element 40 is accommodated in each housing main body 12.
[0026]
The mounting lock portion 16 is configured to be inserted into the engaging hole 74 formed on the wiring board 70 side from the upper surface side of the wiring board 70 so as to be able to engage with the engaging hole 74 in a retaining manner. Have been.
[0027]
Specifically, a pair of mounting lock portions 16 are formed on both side portions of the first housing 11. Each mounting lock portion 16 includes an extended lock piece 16a extending downward from both sides of the first housing 11 and a lock projection 16b formed to protrude from the distal end of each extended lock piece 16a. Have.
[0028]
Each extension lock piece 16a is formed in a long plate shape that can be inserted into an engagement hole 74 formed on the wiring board 70 side.
[0029]
Further, each lock projection 16b is formed so as to protrude outward from a tip end of each extension lock piece 16a, and each lock projection 16b is formed on the lower surface side of the wiring board 70 by the engagement hole portion. 74 are configured to be engageable with the peripheral portion.
[0030]
The distance between the upper surface of each lock protrusion 16 b and the bottom of the first housing 11 is formed to be substantially the same as the thickness of the wiring board 70. In a state where the lock projection 16b is engaged with the periphery of the engagement hole 74 on the lower surface side of the wiring board 70 in a retaining manner, the bottom of the first housing 11 contacts the upper surface of the wiring board 70. As a result, the first housing 11 is positioned in a direction substantially perpendicular to the wiring board 70.
[0031]
In addition, the lower surface of each lock projection 16b is formed as an inclined surface that is inclined inward toward the outside of the first housing 11. Then, when each of the mounting lock portions 16 is inserted into the corresponding one of the engagement holes 74 from above the wiring board 70 side, first, each of the inclined surfaces comes into sliding contact with the peripheral portion of each of the engagement holes 74, and The extension lock piece 16a is elastically deformed inward of the first housing 11. When each lock projection 16b crosses over the inner peripheral portion of each engagement hole 74, each extended lock piece 16a returns to its original linear state, and each lock projection 16b is The lower surface side engages with each of the engagement holes 74 in a retaining shape.
[0032]
Each lock projection 16b serves to keep the bottom of the first housing 11 in close contact with the upper surface of the wiring board 70 when the optical element 40 is surface-mounted on the wiring board 70, as described later. Accomplish. In addition to the lock projection 16b as described above, the bottom of the first housing main body 12 may be formed by fixing the first housing 11 using solder, an adhesive, or the like. Various configurations that can be applied to mount and fix the housing main body 12 to the wiring board 70 in a state where the housing main body 12 is closely arranged on the main surface of the wiring board 70 can be adopted.
[0033]
Further, a substantially U-shaped slit 18 s is formed in the ceiling of each of the first housing main bodies 12, so that a tongue-shaped elastic biasing piece 18 is formed.
[0034]
That is, one side of the outer periphery of the elastic biasing piece 18 is connected to the ceiling of the first housing body 12, and another portion of the outer periphery of the elastic biasing piece 18 is provided through the slit 18s. And is separated from the ceiling of the first housing body 12. The elastic biasing piece 18 is elastically deformable in and out of the ceiling portion around the connection portion of the first housing body 12 with the ceiling portion.
[0035]
Further, a projection 18a is formed on the inner surface of the elastic biasing piece 18 (see FIG. 4). When the optical element 40 is inserted into the element accommodating recess 13, the projection 18 a comes into contact with the upper surface of the element body 40 a of the optical element 40. When the optical element 40 is pushed further into the element accommodating recess 13, the projection 18a is pushed upward, and the elastic biasing piece 18 is elastically deformed upward. In this state, the optical element 40 is urged downward via the protrusion 18a by the elastic restoring force of the elastic urging piece 18.
[0036]
The configuration of the elastic biasing piece 18 is not limited to the above-described one. For example, the protrusion 18a is omitted, and the elastic biasing piece 18 is bent inward of the first housing body 12. You may do so. Instead of forming the tongue-shaped elastic biasing piece 18 by processing the housing body 12 itself, another elastic member such as a leaf spring or a coil spring is disposed on the ceiling in the element accommodating recess 13. Thus, the optical element 40 may be urged toward the bottom.
[0037]
In short, various elastic urging means capable of urging the optical element 40 accommodated in the element accommodating recess 13 toward the bottom can be used as the element urging portion.
[0038]
The second housing 20 is formed of resin or the like, and is configured to be able to be attached and fixed to the wiring board 70 so as to cover the first housing 11 and to be able to fit and connect the optical connector 50 on the other side.
[0039]
That is, the second housing 20 is formed in a substantially flat cylindrical body, and one end of the second housing 20 is formed in the connection cylindrical portion 22 to which the optical connector 50 of the mating side is fitted and connected, and the other end is formed. Are formed in a housing accommodating portion 26 that accommodates the first housing 11 so as to cover the first housing 11.
[0040]
The housing accommodating portion 26 has an internal space capable of accommodating the first housing 11 (see FIGS. 2 and 3). Preferably, since the force applied to the second housing 20 is less likely to act on the first housing 11, the housing housing 26 is provided with a first housing 11 so that the first housing 11 does not directly contact the housing housing 26. It is preferable that the cover is provided with a predetermined gap therebetween.
[0041]
Further, the back side of the housing housing portion 26 is open, and in a state where the first housing 11 is housed in the housing housing portion 26, the back surface of the first housing 11 is externally exposed through the back side opening of the housing housing portion 26. It is exposed to.
[0042]
The connection tube portion 22 is formed in a substantially cylindrical shape into which the optical connector 50 can be fitted, and is disposed at a position surrounding the two guide sleeve portions 14 in a state of being fixedly mounted on the wiring board 70. You.
[0043]
Then, when the mating optical connector 50 is fitted and connected to the connection tube portion 22, the ferrule portion 55 is guided toward the inside of the guide sleeve portion 14.
[0044]
Further, the housing accommodating portion 26 has a lock portion 23 which can be locked to the optical connector 50 side of the mating side.
[0045]
That is, a concave locked portion 51 is formed on the upper surface of the housing of the optical connector 50 on the mating side, and the projecting lock portion 23 is formed on the upper surface side of the inner peripheral portion of the connection tube portion 22 at a position facing the locked portion 51. Is formed. When the two optical connectors 10 and 50 are fitted and connected, the lock portion 23 is engaged with the locked portion 51, and the connection state of the two optical connectors 10 and 50 is maintained.
[0046]
Further, the second housing 20 is provided with a mounting fixing portion 21 that can be fixed to the wiring board 70. The fixing force of the mounting fixing portion 21 to the wiring board 70 is larger than the fixing force of the mounting lock portion 16 to the wiring board 70. Here, in order to more firmly fix the second housing 20 to the wiring board 70, a structure that can be fixed to the wiring board 70 with screws is adopted as an attachment fixing part.
[0047]
That is, a pair of mounting fixing parts 21 having outwardly projecting screw holes 21h are formed on both sides of the second housing 20. Then, in a state where the second housing 20 is disposed on the upper surface of the wiring board 70, screws S are inserted from below the wiring board 70 into the screw insertion holes 71 of the wiring board 70 and screwed into the screw holes 21 h. By fastening, the second housing 20 is fixed to the wiring board 70 with screws.
[0048]
A procedure for mounting and fixing the optical connector 10 thus configured on the upper surface of the wiring board 70 will be described.
[0049]
First, each optical element 40 is accommodated and arranged in each element accommodating recess 13 of the first housing 11. On the other hand, a solder paste is applied to a predetermined area on the wiring pattern 72 side on the wiring board 70 side.
[0050]
Then, while arranging the respective electrode portions 40b of the respective optical elements 40 on the corresponding wiring patterns 72, the respective mounting lock portions 16 are inserted into the respective engaging hole portions 74 from the upper surface side of the wiring board 70, and the respective locking portions are formed. The first housing 11 is attached and fixed to the upper surface of the wiring board 70 by being engaged with the mating hole 74 in a retaining shape.
[0051]
In this state, each optical element 40 is urged toward the upper surface of the wiring board 70 by the elastic restoring force of each elastic urging piece 18. Therefore, the bottom of each optical element 40 is pressed so as to be in close contact with the upper surface of the wiring board 70, and each of the electrode sections 40 b is so close or close enough that the corresponding wiring pattern 72 can be reliably reflow soldered. It is in a state of being arranged.
[0052]
In this state, in a known reflow soldering apparatus, the exposed portion is exposed to a high-temperature atmosphere to melt the solder paste on the wiring pattern 72 and solder the electrode portion 40b of the optical element 40 to the wiring pattern 72.
[0053]
Since the optical elements 40 are soldered while the first housing 11 is attached and fixed to the wiring board 70 in this manner, the mounting position of the first housing 11 and the mounting position of each optical element 40 are different. Hard to slip. Therefore, stress due to the displacement of the mounting position hardly acts on the soldering portion between each electrode portion 40b of each optical element 40 and the wiring pattern 72, and cracks, solder detachment, contact failure and the like of the soldering portion are less likely to occur. There is an advantage that it can be prevented.
[0054]
Next, the second housing 20 is disposed on the wiring board 70 so as to cover the first housing 11, and the screw S is screwed into the screw hole 21 h of the attachment fixing part 21 from below the wiring board 70. Then, the second housing 20 is fixed to the wiring board 70 with screws. At this time, since the first housing 11 and the second housing 20 are formed separately, stress at the time of screw tightening is smaller than that of the conventional example in which they are integrally formed. It is hard to join. In this manner, the first housing 11 is housed in the second housing 20 and is integrally combined.
[0055]
When the optical connector 50 of the mating side is connected to the optical connector 10 mounted and fixed on the wiring board 70 in this way, first, the mating optical connector 50 is inserted and connected to the second housing 20. When the optical connector 50 is inserted further into the back, each ferrule portion 55 is inserted into the corresponding guide sleeve portion 14 and guided toward the optical element 40 in each element accommodating recess 13. When the optical connector 50 is inserted at the innermost position, the end face of each optical fiber 61 is disposed to face the light emitting surface or the light receiving surface of each optical element 40, and the two are optically coupled. In this connection state, the lock portion 23 is engaged with the locked portion 51, and the connection state of the two optical connectors 10, 50 is maintained.
[0056]
That is, when the optical connector 50 is inserted and connected to the second housing 20, rough position guidance of the optical connector 50 is performed, and each ferrule portion 55 is guided toward each guide sleeve portion 14. Then, by inserting the ferrule portions 55 on the optical connector side into the respective guide sleeve portions 14, the optical axes of the optical fiber 61 and the optical element 40 can be aligned with higher accuracy. In addition, since the lock portion 23 of the second housing 20 is engaged with the locked portion 51 of the optical connector 50, the connection between the two optical connectors 10 and 50 is firmly held.
[0057]
According to the optical connector configured as described above, each optical element 40 can be soldered in a state where each optical element 40 is urged toward the upper surface of the wiring board 70 by the elastic urging piece 18. Therefore, each electrode portion 40b of each optical element 40 can be securely soldered to the wiring pattern 72 of the wiring board 70.
[0058]
Further, in the case where the elastic urging piece 18 is formed by forming a substantially U-shaped slit 18 s in the ceiling portion of each housing body 12, a simple configuration is used without using a separate member. be able to.
[0059]
Further, by inserting the mounting lock portion 16 into the engagement hole 74 on the wiring board 70 side, the first housing 11 can be easily engaged with the engagement hole in a retaining shape. 70 can be mounted and fixed.
[0060]
Further, the second housing 20 to which the mating optical connector 50 can be fitted and connected is fixed to the wiring board 70 so as to cover the first housing 11. Even when a large force is applied, the force is received by the second housing 20. Therefore, a large force is less likely to be applied to the first housing 11 and the optical element 40, and stress on the soldered portion can be more reliably prevented.
[0061]
In addition, since the connection state of the two optical connectors 10 and 50 is maintained by the engagement of the locking portion 23 with the locked portion 51, the optical fiber 61 is pulled, for example, so that the optical connector 50 is pulled out. When the second force is applied, the force is received by the second housing 20, and also in this respect, the stress on the soldered portion can be more reliably prevented.
[0062]
In the present embodiment, use in an environment where vibration or a large force is applied to the optical connector 50 or the optical fiber 61, such as use in an automobile, is assumed. When used in an environment where such vibration or force is unlikely to be applied, the second housing 20 may be omitted, or the first housing 11 and the second housing 20 may be integrally formed. .
[0063]
Further, in the present embodiment and its modifications, the so-called two-pole type optical connector 10 including two optical elements 40 has been described, but the same applies to a one-pole type or a multi-pole type optical connector having three or more poles. Applicable to
[0064]
【The invention's effect】
As described above, according to the optical connector of the first aspect of the present invention, the optical element can be soldered in a state where the optical element is urged toward the main surface of the wiring board by the element urging portion. Therefore, the electrode portion of the optical element can be securely soldered to the wiring pattern of the wiring board.
[0065]
According to the second aspect of the present invention, the first housing can be easily mounted and fixed on the wiring board by inserting the mounting lock portion into the engagement hole on the wiring board side and engaging it. .
[0066]
According to the third aspect of the present invention, the tongue-shaped elastic biasing piece is formed by forming a substantially U-shaped slit in the ceiling of the housing body, so that another separate member is provided. , And a simple configuration can be achieved.
[0067]
According to the fourth aspect of the invention, when a large external force is applied to the mating optical connector or the like, the force is received by the second housing, so that a large force is applied to the first housing or the optical element. And the stress on the soldered portion can be more reliably prevented.
[0068]
According to the fifth aspect of the invention, even when a force in the pull-out direction is applied to the mating optical connector, the force is received by the second housing, and therefore, the stress on the soldered portion is reduced. It can be reliably prevented.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing an optical connector.
FIG. 2 is a sectional view showing the optical connector according to the first embodiment;
FIG. 3 is a perspective view showing a state where the optical connector is mounted and fixed on a wiring board.
FIG. 4 is a sectional view showing a first housing.
FIG. 5 is a cross-sectional view showing a state where an optical element is accommodated and arranged in a first housing.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Optical connector 11 1st housing 12 1st housing main body 13 Element accommodating recess 14 Guide sleeve 16 Attachment locking part 18 Elastic biasing piece 18s Slit 20 Second housing 21 Attachment fixing part 23 Locking part 40 Optical element 40a Element main part 40b Electrode part 50 Optical connector 51 Locked part 55 Ferrule part 61 Optical fiber 70 Wiring board 72 Wiring pattern 74 Engagement hole

Claims (5)

An optical connector mounted on a main surface of a wiring board with an optical element housed therein,
A surface-mounted optical element in which an electrode section is formed on the surface of the element body,
A housing main body portion having an element accommodating recess for accommodating and holding the optical element in a state capable of being surface-mounted on the wiring board; and a guide sleeve section for guiding an optical fiber so as to be optically connectable to the optical element. A first housing having a mounting portion for mounting and fixing the housing main body to the wiring board in a state where the bottom of the housing main body is closely arranged on the main surface of the wiring board;
With
An optical connector, wherein an element urging portion for urging the optical element toward a main surface of the wiring board is provided in the housing body. The optical connector according to claim 1, wherein
The mounting portion is a mounting lock portion that can be inserted into the engaging hole formed on the wiring board side from the main surface side of the wiring board so as to be able to engage with the engaging hole in a retaining shape. , Optical connector. The optical connector according to claim 1 or 2, wherein
The element urging unit,
An optical connector, which is a tongue-shaped elastic biasing piece formed by forming a substantially U-shaped slit in a ceiling portion of the housing body. The optical connector according to claim 1, wherein:
The optical fiber is guided toward the guide sleeve portion by being attached and fixed to the wiring board so as to cover the first housing, and by fittingly connecting the housing of the mating optical connector holding the optical fiber. An optical connector, further comprising: a second housing. The optical connector according to claim 4, wherein
The optical connector, wherein the second housing has a lock portion that can be locked to a counterpart optical connector.

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