JP2006234854A - Holder for optical connector and FOT and ferrule holding structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a holder for an optical connector and a holding structure for an FOT and a ferrule as components and structures contributing to reduction of the number of components and light loss.
A holder 7 for an optical connector 1 includes a base member 7a, and a piece-like first piece portion 7b and a second piece portion 7c provided on the base member 7a. The first piece-like portion 7b is formed as a portion that contacts the rear surface 5d of the FOT 5 attached to the FOT case 6 as a housing. The second piece 7c is formed as a portion that contacts the flange 4d of the ferrule 4b located on the front surface 5c side of the FOT 5. Furthermore, the first piece-like portion 7b and / or the second piece-like portion 7c is provided with a spring property.
[Selection] Figure 1

Description

  The present invention relates to a holder for holding an FOT (Fiber Optic Transceiver) and a ferrule constituting an optical connector, and a holding structure using the holder.

  In an optical fiber communication system, an optical connector is used to convert an optical signal transmitted from an optical fiber cable into an electrical signal or to convert an electrical signal from a substrate into an optical signal. The optical connector includes a receptacle-type optical connector and a plug-type optical connector that fits into the receptacle-type optical connector.

  The receptacle type optical connector includes an FOT having a light emitting element and a light receiving element, an optical connector housing for fixing the FOT, a light guide member, and the like, and is configured to be attached to a substrate. On the other hand, a plug-type optical connector is a ferrule provided at the end of an optical fiber cable, a plug housing that accommodates the ferrule, a spring member that applies a biasing force to the ferrule, and holds the spring member and fits into the plug housing And a spring pressing member.

In such a configuration, when the plug-type optical connector is fitted to the receptacle-type optical connector, the ferrule is subjected to the urging force from the spring member, so that the distance between the ferrule and the FOT is minimized. As a result, the optical loss is reduced (see, for example, Patent Document 1).
JP-A-11-174277

  As can be seen from the above, the conventional optical connector is composed of many parts. In other words, the optical signal cannot be converted into an electrical signal or the electrical signal cannot be converted into an optical signal unless many parts are provided. The conventional optical connector has a problem that the number of parts is large.

  Further, in the conventional optical connector, the optical connector housing and the plug housing are fitted to each other by a locking projection of the locking arm and a locking recess on which the locking projection is caught. Such a fitting structure is designed so that a slight backlash occurs. The conventional optical connector has a problem that the optical axis may be shifted due to the fitting backlash.

  The present invention has been made in view of the above-described circumstances, and provides a holder for an optical connector and a holding structure for an FOT and a ferrule as components and structures that contribute to the reduction of the number of parts and the reduction of optical loss. Let it be an issue.

  The holder for an optical connector of the present invention according to claim 1, which has been made to solve the above problems, comprises a base member, and a piece-like first piece portion and a second piece-like portion provided on the base member. And the first piece is formed as a portion that contacts the rear surface of a FOT (Fiber Optic Transceiver) attached to the housing, and the second piece is formed on the front side of the FOT. The first piece-like part and / or the second piece-like part is provided with a spring property.

  According to the present invention having such a feature, the FOT and the ferrule are used in a state in which the FOT and the ferrule are opposed to each other in the housing, or the FOT and the ferrule are used in the housing with the light guide member interposed therebetween. Be able to. The FOT and the ferrule are sandwiched simultaneously by the first piece and the second piece of the holder of the present invention. The positional relationship between the FOT and the ferrule sandwiched between the holders is fixed and optically connected.

  At a minimum, an optical connection is possible if the FOT, the ferrule, the housing, and the holder of the present invention are provided. That is, according to the present invention, optical connection is possible with a small number of parts. Since the holder of the present invention fixes the positional relationship between the FOT and the ferrule, it contributes to light loss reduction.

  Considering the case where the ferrule is fitted to the housing in a state where it is housed in another housing, the number of constituent members is increased by one from the minimum configuration, but optical connection is naturally possible. That is, the holder according to the present invention fixes the positional relationship between the FOT and the ferrule by sandwiching the FOT and the ferrule, and thus absorbs the fitting play necessary for fitting between the housing and another housing. It becomes possible. The holder of the present invention contributes to light loss reduction even when the ferrule is housed in another housing.

  A holder for an optical connector according to a second aspect of the present invention is the holder for an optical connector according to the first aspect, wherein the holder and / or the substrate are provided in a portion different from the portion having the spring property. It is characterized by forming a fitting portion to be fitted.

  According to the present invention having such characteristics, the holder is fitted to the housing and / or the substrate. This prevents the holder from falling off. If a fitting portion that fits in two stages is formed, two states of temporary locking and permanent locking can be obtained. Since the FOT and the ferrule are sandwiched simultaneously by the first piece-shaped portion and the second piece-shaped portion of the holder, the fitting play of the holder itself is not related. By forming the fitting portion, the reliability of the holder of the present invention can be improved.

  According to a third aspect of the present invention, there is provided a FOT and ferrule holding structure according to a third aspect of the present invention, wherein the optical connector holder according to the first or second aspect is used. Fiber Optic Transceiver) and a ferrule located on the front side of the FOT are held by being sandwiched.

  According to the present invention having such a feature, the positional relationship between the FOT and the ferrule sandwiched between the holders is fixed and the optical connection is made. Since the holder fixes the positional relationship between the FOT and the ferrule, such a holding structure contributes to light loss reduction.

  According to the first and third aspects of the present invention, it is possible to contribute to the reduction of the number of parts and the reduction of optical loss. In addition, according to the present invention, the reliability of the holder can be improved.

Hereinafter, description will be given with reference to the drawings.
FIG. 1 is an exploded perspective view of an optical connector showing an embodiment of the present invention (the circle is an enlarged perspective view of a holder). 2 is a cross-sectional view of the optical connector showing a temporarily locked state of the holder, and FIG. 3 is a cross-sectional view of the optical connector showing a fully locked state of the holder.

  In FIG. 1, reference numeral 1 indicates an optical connector mounted on the substrate 2 and housed in the housing 3 together with the substrate 2 (referred to as an optical connector in a state including the substrate 2 and the housing 3). Is also good). The optical connector 1 is a component used in an optical fiber communication system, and includes a ferrule assembly 4, a pair of FOT (Fiber Optic Transceiver) 5, a FOT case 6, a holder 7 of the present invention, and a shield case 8. (Refer to FIG. 2). Here, the optical connector 1 is composed of five components (assumed to be an example). Hereinafter, each component will be described with reference to FIGS. 1 to 3.

  A plurality of circuits are formed on the substrate 2. Also, electronic components and the like are mounted on this circuit. Such a substrate 2 includes a plurality of connecting portions 2a of the FOT 5 with respect to a lead frame 5a, which will be described later, a plurality of through holes 2b with respect to a fixing portion 6a and a positioning projection 6b, which will be described later, and an opening 2c with respect to the holder 7. And are formed. Reference numeral 2 d indicates a plurality of connection portions used for electrical connection from the outside of the housing 3.

  The casing 3 includes an upper case 3a and a lower case 3b made of a synthetic resin having insulating properties. The upper case 3 a has an internal space 3 c that houses the optical connector 1. The upper case 3a is formed with an optical fiber cable opening 3d communicating with the internal space 3c and a connector 3e for electrical connection from the outside. The lower case 3b has a shallow bottom, and a step portion 3f for holding the substrate 2 is formed inside the side wall.

  The ferrule assembly 4 includes a ferrule 4b provided at each end of the pair of optical fiber cables 4a and a waterproof cap 4c. The ferrule 4b has a substantially cylindrical shape, and two flanges 4d and 4e are formed on the outer peripheral surface. The flanges 4d and 4e are arranged at a predetermined interval. The flange 4d is formed so as to function as a stopper in the FOT case 6 and also as a step portion of the ferrule 4b. A known method is used for fixing the optical fiber cable 4a and the ferrule 4b. The waterproof cap 4c is made of rubber, for example, and is formed to be watertight with respect to the optical fiber cable 4a and the optical fiber cable opening 3d.

  The FOT 5 includes a plurality of lead frames 5a that are electrically connected to the connection portion 2a of the substrate 2, and a package portion 5b that incorporates a light emitting element (for example, LD or LED) or a light receiving element (for example, PD) (not shown). is doing. A light emitting element or a light receiving element (not shown) is arranged so as to be able to face from the front surface 5c of the package part 5b. The rear surface 5d of the package part 5b is formed flat and has a function as a surface for receiving pressure.

  The FOT case 6 is a member corresponding to the housing described in the claims, and is formed using a synthetic resin material having insulating properties. On the outside of the FOT case 6, a fixing portion 6a and a positioning projection 6b for the substrate 2 are formed. The fixing part 6a is formed as a screwing part. Inside the FOT case 6, a ferrule storage space 6c and a FOT storage space 6d are formed.

  The ferrule storage space 6 c is formed so as to open the front surface of the FOT case 6. In the ferrule storage space 6c, a step portion (reference numeral omitted) on which the flange 4d of the ferrule 4b abuts is formed. The FOT storage space 6 d is formed so as to open the rear surface of the FOT case 6. The ferrule storage space 6c and the FOT storage space 6d are formed so as to communicate with each other.

  Reference numeral 6e indicates an insertion fitting portion of the holder 7 with respect to a second piece portion 7c described later. The insertion fitting portion 6e is formed so as to communicate with the ferrule storage space 6c. Moreover, the insertion fitting part 6e is formed so that the FOT case 6 may be penetrated in the up-down direction. The FOT case 6 is also formed with a portion to be fitted to a fitting portion 7h, which will be described later, of the holder 7, although not particularly shown.

  The holder 7 is a member that characterizes the present invention, and is formed of a synthetic resin material. The holder 7 includes a base member 7a, and a piece-like first piece portion 7b and a second piece portion 7c provided on the base member 7a. The base member 7a is a flat plate-like portion that is front and back and is formed to have sufficient rigidity. The first piece-like part 7b is coupled to one end of the base member 7a. The second piece 7c is coupled to the other end of the base member 7a. The first piece portion 7b and / or the second piece portion 7c has a spring property (in this embodiment, both the first piece portion 7b and the second piece portion 7c have a spring property. ing). An example of a method for imparting spring property is to form the first piece portion 7b and / or the second piece portion 7c so as to be inclined slightly inward rather than perpendicular to the base member 7a.

  The first piece 7b has a base end portion 7d continuous with the base member 7a and a contact pressing portion 7e that contacts and presses the rear surface 5d of the FOT 5. The second piece 7c has a central shaft portion 7f that is continuous with the base member 7a and located at the center, and ferrule holding portions 7g that are located on both sides of the central shaft portion 7f. The tip of the ferrule holding portion 7g is formed in an arc shape. The ferrule holding portion 7g is formed so as to be able to contact and hook the flange 4d of the ferrule 4b.

  The holder 7 is formed with fitting portions 7h and 7i. One fitting portion 7h is formed so as to be fitted to a fitted portion (not shown) of the FOT case 6. One fitting portion 7h is formed to be an arm-shaped locking projection. One fitting portion 7h is formed on the base member 7a (this is an example. Other portions may be used as long as they do not have spring properties). The other fitting part 7i is formed in the second piece-like part 7c. The other fitting portion 7 i is formed so as to fit into the insertion fitting portion 6 e of the FOT case 6. Here, the other fitting portion 7i is composed of two types of projections for temporary locking (upper projections) and main locking projections (lower two projections) (one example). And). The fitting portion may be fitted to the substrate 2.

  The shield case 8 is formed by pressing a conductive metal thin plate. The shield case 8 is formed so as to cover the FOT 5 and take countermeasures against electromagnetic noise.

  Next, assembly of the optical connector 1 will be described based on the above configuration (assuming that the assembly procedure is an example).

  First, the FOT 5 is simply inserted into the FOT storage space 6d of the FOT case 6 and attached. The FOT 5 is inserted into the FOT storage space 6d from the front surface 5c. Next, the FOT case 6 and the FOT 5 are mounted at predetermined positions on the substrate 2. At this time, the shield case 8 is also mounted. Subsequently, the ferrule 4b drawn into the internal space 3c through the optical fiber cable opening 3d of the upper case 3a is simply inserted into the ferrule storage space 6c of the FOT case 6 and attached. The ferrule 4b is inserted in a state where the tip end face has a slight gap with respect to the front face 5c of the FOT 5 (the gap is for protecting the end face of the optical fiber).

  Subsequently, the holder 7 is attached to the FOT case 6, FOT 5, and ferrule 4 b through the opening 2 c of the substrate 2. As the attachment of the holder 7, first, temporary locking is performed in which the temporarily locking fitting portion 7 i is fitted to the insertion fitting portion 6 e of the FOT case 6. In addition, when the holder 7 is temporarily locked, the waterproof cap 4c is aligned and other adjustments are performed.

  Next, the temporarily locked holder 7 is brought into a fully locked state. This is done by pushing the holder 7 to the end. In the main locking state, the main locking fitting portion 7i and the insertion fitting portion 6e are fitted, and the fitting portion 7h and the fitted portion (not shown) of the FOT case 6 are fitted. . When the holder 7 is fully locked, the FOT 5 and the ferrule 4b are sandwiched between the first piece 7b and the second piece 7c. At this time, the FOT 5 is pushed toward the ferrule 4b, and the flange 4d of the ferrule 4b is pushed against the step portion of the FOT storage space 6d. The positional relationship between the FOT 5 and the ferrule 4 b is fixed by the holder 7.

  Finally, the lower case 3b is attached to the upper case 3a, and a series of assembly is completed.

  As described above with reference to FIGS. 1 to 3, according to the present invention, the holder 7 is used to sandwich the FOT 5 and the ferrule 4 b and fix their positional relationship. Therefore, the holder 7 and the holding structure of the FOT 5 and the ferrule 4b using the holder 7 can reduce light loss as compared with the conventional case. Further, as can be understood from the above description, the present invention can configure the optical connector 1 with a small number of constituent members (for example, optical connection can be made without using a housing for the ferrule 4b).

  Another embodiment of the present invention will be described with reference to FIG. FIG. 4 is a cross-sectional view of an optical connector showing another embodiment of the present invention.

  In FIG. 4, an optical connector 11 includes a receptacle-type optical connector 12, a plug-type optical connector 13 that fits into the receptacle-type optical connector 12, and a holder 14 that has the same function as the above-described holder 7. It is prepared for.

  The receptacle-type optical connector 12 includes an FOT 15, an optical connector housing 16 that fixes the FOT 15, and a shield case 17. On the other hand, the plug-type optical connector 13 includes a ferrule 19 provided at the end of the optical fiber cable 18 and a plug housing 20 that accommodates the ferrule 19.

  In the above configuration, when the receptacle-type optical connector 12 and the plug-type optical connector 13 are fitted and the holder 14 is attached as illustrated, the first piece-like portion 14a and the second piece-like portion 14b of the holder 14 FOT 15 and ferrule 19 are sandwiched. These positional relationships are fixed.

  Since the positional relationship between the FOT 15 and the ferrule 19 is fixed, the holder 14 can contribute to light loss reduction as in the above-described embodiment. Note that the holder 14 here is mounted across the optical connector housing 16 and the plug housing 20, and therefore can absorb the fitting play necessary for fitting the optical connector housing 16 and the plug housing 20. it can.

  In addition, it goes without saying that the present invention can be variously modified without departing from the spirit of the present invention. That is, for example, a light guide member may be interposed between the FOT 5 and the ferrule 4b.

1 is an exploded perspective view of an optical connector showing an embodiment of the present invention (the circle is an enlarged perspective view of a holder). It is sectional drawing of the optical connector which shows the temporary latching state of a holder. It is sectional drawing of the optical connector which shows the main latching state of a holder. It is sectional drawing of the optical connector which shows other one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical connector 2 Board | substrate 2c Opening part 3 Housing | casing 4 Ferrule assembly 4a Optical fiber cable 4b Ferrule 4d Flange (step part)
5 FOT
5a Lead frame 5b Package part 5c Front 5d Rear 6 FOT case (housing)
6c Ferrule storage space 6d FOT storage space 6e Insertion fitting portion 7 Holder 7a Base member 7b First piece portion 7c Second piece portion 7d Base end portion 7e Contact pressing portion 7f Center shaft portion 7g Ferrule holding portion 7h, 7i Fit Joint part 8 Shield case

Claims (3)

A base member and a piece-like first piece portion and a second piece portion provided on the base member, the first piece portion being in contact with the rear surface of the FOT (Fiber Optic Transceiver) attached to the housing And the second piece is formed as a portion in contact with the step portion of the ferrule located on the front side of the FOT, and the first piece and / or the second piece is further formed. A holder for an optical connector, characterized in that the piece-like part has a spring property. In the holder for optical connectors according to claim 1,
A fitting portion that is fitted to the housing and / or the substrate is formed in a portion different from the portion having the spring property. A holder for an optical connector according to claim 1 or claim 2, wherein a FOT (Fiber Optic Transceiver) attached to the housing and a ferrule located on the front side of the FOT are held by being sandwiched. Holding structure for FOT and ferrule.

Images