JP2005189486A - Optical fiber switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical fiber switch which is capable of effectively taking out a shape restoring force of shape memory alloy as a power source and has a quick switching time. <P>SOLUTION: The optical fiber switch 1 is provided with a switch substrate 2, a movable optical fiber 3 of which one part 3a is fixed to the switch substrate 2 and the top end part 3b is swingable and two pieces of stationary optical fibers 4R, 4L which are opposed to the top end part 3b of the movable optical fiber 3 and are juxtaposed on the switch substrate 2. Therein, the top end part 3b is allowed to swing and, thereby, the movable optical fiber 3 is optically connected with either one of the two pieces of stationary optical fibers 4R, 4L. The optical fiber switch 1 is further provided with a swingable driving mechanism 24 which energizes either one side of a right swingable member 6R and a left side swingable member 6L made of shape memory alloy and heats the same, an alignment mechanism 25 which allows the center of the top end part 3b of the movable optical fiber to coincide with the centers of the stationary optical fibers 4R, 4L and a latch mechanism 8 which retains the top end part 3b in a swingable state. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a mechanical optical fiber switch used in an optical transmission system, and more particularly, to an optical fiber switch that performs switching using a shape restoring force of a shape memory alloy as a power source.

  In recent years, optical communication and optical transmission technology using a single-mode optical fiber that can send a large amount of information at high speed has dramatically increased, and its infrastructure has been developed at a tremendous speed on a city-by-city basis. Has been. On the other hand, in small units such as small hospitals, nursing homes, homes and offices, networks using POF (plastic optical fiber) and PCF (plastic clad fiber) are multimode optical fibers that are much easier to handle than quartz optical fibers. Is garnering attention. Of course, there is no doubt that these quartz optical fibers and POF and PCF will be appropriately combined in the near future to become the main body of the information communication network.

  In this information communication network, an optical fiber switch is required for each branching unit in order to individually transmit information from the outside or information from other locations in the interior to each information terminal, OA device, or the like. Therefore, development of a small-sized, low-loss, low-cost, highly stable self-holding optical fiber switch is urgently needed.

  As this type of optical fiber switch, for example, one described in Patent Document 1 is known. Such an optical fiber switch is composed of a switch body, a movable optical fiber (for example, POF, PCF, etc.) that is partially fixed to the switch body and capable of swinging at the tip, and two optical fibers arranged in parallel above and below the movable optical fiber. The movable optical fiber is optically connected to one of the two stationary optical fibers by swinging the tip portion.

  This optical fiber switch is characterized in that a shape memory alloy wire is joined to the upper and lower surfaces of the movable optical fiber along the longitudinal direction of the movable optical fiber. The shape memory alloy forming this shape memory alloy wire has a unidirectional property and is set with tensile deformation. When heated by energization, the shape memory alloy shrinks to the memorized length and heat is removed. Can also keep the contraction length.

  According to such an optical fiber switch, by energizing one of the upper and lower shape memory alloy wires, the wire is heated and contracted, and the fiber is sandwiched from above and below by using the shape restoring force (contraction force) of the wire as a power source. The tip of the movable optical fiber can be swung vertically and optically connected to one of the two stationary optical fibers.

  Specifically, the tip of the movable optical fiber swings in the vertical direction in a rhombus-shaped space formed by assembling a pair of halved ferrules (swing guide members) formed with V grooves. Then, it is optically connected to one of the stationary optical fibers respectively disposed at the upper and lower ends in the space.

  This optical fiber switch is excellent in that it is a self-holding type and an ultra-small size by skillfully combining flexibility such as POF and shape restoring force of a shape memory alloy.

JP-A-7-56097

  By the way, in the said optical fiber switch, since it is set as the structure which joined the shape memory alloy wire along the movable optical fiber, the subject as described below can be considered.

  First, since the movable optical fiber is actually extremely thin with a diameter of 1.0 mm or 0.5 mm, it is not possible to join shape memory alloy wires in parallel on both the upper and lower surfaces of the movable optical fiber. Realistic and difficult to implement.

  Second, when the shape memory alloy wire is energized and heated to contract, the optical fiber to which the shape memory alloy wire is bonded must be contracted together, and the contraction force of the shape memory alloy wire is reduced. It is consumed by the contraction of the optical fiber. Therefore, in order to bend the optical fiber on the principle of bimetal, it is necessary to wait until the shape memory alloy wire is greatly contracted, and switching takes time.

  Third, since the shape memory alloy wire is bonded over substantially the entire length (from the fixed portion to the tip portion) of the movable optical fiber, when the shape memory alloy wire is energized and heated, the movable optical fiber has a substantially full length. The tip surface is deformed into an arc shape and the tip surface thereof does not face the tip surface of the stationary optical fiber. Therefore, the clearance between the two increases, and the leakage of transmitted light energy increases.

  In addition, fourthly, when the contraction force of the shape memory alloy wire acts on the movable optical fiber, the behavior of the tip of the movable optical fiber can only be controlled indirectly as if the tip of a fishing rod. In the formed V-groove, arbitrary movement was allowed, and stable switching behavior was difficult to obtain, that is, switching took time.

  An object of the present invention created in view of the above circumstances is to provide an optical fiber switch that can effectively extract the shape restoring force of a shape memory alloy as a power source and has a fast switching time.

The present invention was devised to solve the above-mentioned problems. The switch board, the movable optical fiber partially fixed to the switch board and swingable at the tip, and the switch facing the tip of the movable optical fiber. An optical fiber switch that optically connects the movable optical fiber to one of the two stationary optical fibers by swinging the tip portion, and comprising two stationary optical fibers arranged in parallel on the substrate,
A right-hand swinging member made of a shape memory alloy having one end fixed to the tip and the other end fixed to the switch board on the right side of the tip, and one end fixed to the tip and the other end to the left of the tip A drive mechanism having a left swing member made of a shape memory alloy fixed to the switch board, and an energization device that generates heat by energizing either the right swing member or the left swing member;
The switch board has a front stopper and a rear stopper provided at predetermined intervals in the longitudinal direction of the movable optical fiber so that the swing member is sandwiched between the switch board, and by limiting the swing amount of the tip part, An alignment mechanism that aligns the center with the center of the stationary optical fiber;
A pair of magnets disposed on both sides of the tip portion between the front stopper and the rear stopper on the switch board, and the right swing member and the left neck mounted on the tip portion A latch mechanism having a magnetic attraction member made of a magnetic material to which the swing member is fixed, and holding the tip in a swinging state;
It is equipped with.

  Moreover, it is preferable that the said right swinging member and the left swinging member are integrally formed, and consist of one member.

  Moreover, it is preferable that the said right swing member and left swing member are formed in a coil shape.

  The switch board is preferably provided with a recess for accommodating the swinging member, stopper, latch mechanism, movable and stationary optical fibers.

  According to the present invention, the following effects can be exhibited.

  (1) When swinging the tip of the movable optical fiber, the shape restoring force of the shape memory alloy of the right and left swinging members of the drive mechanism can be applied directly to the tip from the lateral direction. The shape restoring force of the memory alloy can be effectively transmitted as the power for swinging the tip, and the switching time is increased.

  (2) When the distal end portion of the movable optical fiber is swung by the drive mechanism, the distal end portion can be moved parallel to the stationary optical fiber by the alignment mechanism and the latch mechanism, so that the axes of both can be aligned. Therefore, the leakage of transmitted light energy can be reduced.

  (3) Even if the swinging member is turned off after the tip of the movable optical fiber is swung, since the swinging state of the tip can be maintained by the latch mechanism, wasteful power consumption can be avoided.

  (4) Since the swinging member is indirectly attached to the movable optical fiber via the magnetic attraction member, the movable optical fiber is not damaged when the swinging member is attached to the movable optical fiber.

  (5) If the right swing member and the left swing member are integrally formed as one member, the number of steps can be reduced and the cost can be reduced. In this case, by attaching the center of the integrally formed swinging member to the tip and fixing both ends to the switch board, the right swinging member and the left swinging member are installed. By energizing any one of these members, an electric circuit that swings the tip in a desired direction can be obtained.

  (6) If the right and left swing members are coiled, when one of them contracts, the other will not obstruct it, and almost all of the contraction force of the member is used for swinging the tip. it can.

  (7) If the switch board is provided with a swinging member, stopper, latch mechanism, movable and stationary optical fiber recesses, the optical fiber switch can be hermetically sealed by providing a cover that covers the recesses on the board, and dust and humidity The switch can be protected from changes and the like. Therefore, there is no problem with the installation location of the switch.

  Preferred embodiments of the present invention will be described with reference to the accompanying drawings.

  1 is a perspective view of an optical fiber switch according to the present embodiment, FIG. 2 is a plan view of the optical fiber switch, and FIG. 3 is a sectional view taken along line III-III in FIG.

  As shown in FIGS. 1 and 2, the optical fiber switch 1 includes a switch substrate 2 made of plastic such as acrylic, and a movable optical fiber in which a part (root portion) 3a is fixed to the substrate 2 and a tip portion 3b can swing. 3 and a right stationary optical fiber 4R and a left stationary optical fiber 4L arranged in parallel on the substrate 2 so as to oppose the distal end portion 3b of the movable optical fiber 3, and the movable optical fiber 3 is separated by swinging the distal end portion 3b. One of the stationary optical fibers 4R and 4L is optically connected.

  The movable and stationary optical fibers 3, 4R and 4L are multimode optical fibers having sufficient flexibility made of plastic such as POF or PCF, both having the same type and the same core diameter. It has been. These movable and stationary optical fibers 3, 4R, 4L have a sufficient length of several tens of centimeters to several tens of meters or several hundreds of meters in order to establish a network, and the end portion on the side not mounted on the substrate 2 has information. Each is connected to an optical terminal such as a terminal or an OA device. Each of the optical fibers 3, 4R, 4L has a diameter of about 0.5 mm in the illustrated example.

  The substrate 2 is formed in a substantially rectangular parallelepiped shape, and when a POF having a diameter of 0.5 mm is used for the optical fibers 3, 4 </ b> R, and 4 </ b> L, in the illustrated example, the minimum size is 30 mm in length, 10 mm in width, and 3 mm in thickness. ing. However, it is not restricted to this dimension and size. On the upper surface 2a of the substrate 2, in addition to the movable optical fiber 3 and the stationary optical fibers 4R and 4L, each component (a swinging member of a driving mechanism, a stopper of an alignment mechanism, a magnet of a latch mechanism, a magnetic attraction member, etc., which will be described later). A recess 5 is formed to accommodate the.

  The concave portion 5 accommodates a first concave portion 5a in which the root portion 3a of the movable optical fiber 3 is fitted and fixed, and an intermediate portion 3c of the movable optical fiber 3 (a portion between the root portion 3a and the tip portion 3b). 2 concave portion 5b, tip portion 3b of movable optical fiber 3, swing member 6 of drive mechanism 24 for swinging tip portion 3b, stopper 7 of alignment mechanism 25 for limiting the swing amount of tip portion 3b, tip portion A third recess 5c in which the magnet 23 and the like of the latch mechanism 8 for holding 3b in a swinging state are accommodated, and a fourth recess 5d in which the two stationary optical fibers 4R and 4L are fitted and fixed in parallel. Are connected to each other.

  As shown in FIG. 4, the first recess 5 a is disposed at one end of the substrate 2 and has a width (for example, about 0.5 mm) that can accommodate the base portion 3 a of the movable optical fiber 3 (for example, an outer diameter of about 0.5 mm) without a gap. ) And the base 3 a has a depth (for example, about 1 mm) that does not protrude from the upper surface 2 a of the substrate 2, and is formed of a linear groove formed along the longitudinal direction of the substrate 2. In the example shown in the figure, the groove forming the first recess 5 a has a rectangular cross section, but the bottom 5 ax may be arcuate to match the outer shape of the movable optical fiber 3. The root 3a of the movable optical fiber 3 is fitted into the first recess 5a and is installed on the bottom 5ax, and is fixed by an adhesive or the like.

  As shown in FIG. 5, the second recess 5b has a width (for example, about 1 mm) that allows the intermediate portion 3c of the movable optical fiber 3 to swing in the width direction of the substrate 2 with the base portion 3a as a fulcrum. The groove has a rectangular cross section having the same depth as the first recess 5 a and is formed in a straight line along the longitudinal direction of the substrate 2. The second recess 5b is formed such that its center line coincides with the center line of the first recess 5a.

  The width of the groove forming the second recess 5b is set to about twice the diameter of the movable optical fiber 3 in the illustrated example, but is not limited to this. The second concave portion 5b accommodates the intermediate portion 3c of the movable optical fiber 3, and the intermediate portion 3c is placed on the bottom portion 5bx of the second concave portion 5b. The bottom portion 5bx is formed on a smooth plane so as to ensure smooth sliding movement of the intermediate portion 3c placed on the bottom portion 5bx when the intermediate portion 3c is swung around the root portion 3a. ing.

  As shown in FIG. 1, the fourth recess 5d is arranged at the other end of the substrate 2 and fixes the ends of the two stationary optical fibers 4R and 4L in parallel. As shown in FIG. The stationary optical fibers 4R and 4L (outer diameter: about 0.5 mm) can be accommodated in parallel in the width direction of the substrate 2 (for example, about 1 mm), and the depth is the same as the first and second recesses 5a and 5b. It is formed of a groove having a rectangular cross section and is formed in a straight line along the longitudinal direction of the substrate 2. The fourth recess 5d is formed such that its center line coincides with the center line of the first recess 5a.

  The groove forming the fourth recess 5d has a rectangular cross section, but the bottom 5dx may have a shape in which arcs are connected to match the outer shape of the stationary optical fibers 4R and 4L. The ends of the stationary optical fibers 4R and 4L are fitted into the fourth recess 5d and are installed on the bottom 5dx, and are fixed by an adhesive or the like.

  As shown in FIG. 3, the third recess 5 c includes a center protrusion 5 cx formed at the center in the width direction of the substrate 2, an intermediate recess 5 cy disposed on both sides thereof, and both ends disposed on both sides thereof. The concave portion 5cz is connected to the concave portion 5cz. The third recess 5c is positioned so that the tip 3b of the movable optical fiber 3, the swinging member 6 of the drive mechanism 24 that swings the tip 3b, and the center of the tip 3b coincide with the centers of the stationary optical fibers 4R and 4L. The stopper 7 as the mechanism 25, the magnet 23 of the latch mechanism 8 that holds the tip 3b in a swinging state, and the magnetic attraction member 9 are all housed below the upper surface 2a of the substrate 2.

  The drive mechanism 24 swings the tip 3b of the movable optical fiber 3 in the direction in which the stationary optical fibers are juxtaposed, and has a swing member 6 that functions as a substantial actuator. As shown in FIGS. 1 to 3, the swinging member 6 is an elongated coil shape made of a shape memory alloy, and is arranged in the juxtaposed direction (the width direction of the substrate 2) in the juxtaposed plane of the stationary optical fibers 4R and 4L. The tip 3b of the movable optical fiber 3 is disposed along the substantially right angle.

  The central portion of the swing member 6 is attached to a magnetic attracting member 9 that forms part of the latch mechanism 8, and both end portions are attached to thin film members 10 provided in the both end recessed portions 5 cz. In addition, the thin film member 10 is a conductor formed by sputtering, vapor deposition, printing, or the like on the bottom surface of the both-end concave portions 5cz.

  In this way, by fixing the central portion of one swinging member 6 (made of shape memory alloy) arranged so as to cross the distal end portion 3b to the suction member 9 via the central contact member 11c, the above-mentioned swinging is performed. In the member 6, a right portion from the central contact member 11c forms a right swing member 6R, and a left portion from the central contact member 11c forms a left swing member 6L. That is, the swing member 6 is configured by integrally forming a right swing member 6R and a left swing member 6L.

  One end of the right swinging member 6R is attached to the magnetic attraction member 9 via the center contact member 11C, and the other end is attached to the right thin film member 10 via the right contact member 11R. The left swinging member 6L has one end attached to the magnetic attraction member 9 via the center contact member 11C and the other end attached to the left thin film member 10 via the left contact member 11L. Each contact member 11R, 11L, 11C is, for example, a solder ball.

  These right and left swinging members 6R, 6L are formed in a coil shape, and generate heat when energized to contract their entire length. Specifically, the shape memory alloys that form the right and left swinging members 6R and 6L are unidirectional and are set by being subjected to tensile deformation. However, after the power is turned off and the heat is removed, this restoring force is lost.

  FIG. 3 schematically shows the right and left swinging members 6R and 6L in a neutral state. In actuality, when the switch 1 according to the present embodiment is assembled, the suction member 9 is attracted to either the left or right magnet 23 and the tip portion 3b comes into contact with the stopper 7. Neutral state is not realized.

  As shown in FIG. 3, the right and left swinging members 6R and 6L are formed in the same length and the same coil shape before energization, and the right and left contact members 11R and 11L are The movable optical fiber 3 is arranged symmetrically with respect to a vertical line L passing through the center line of the root portion 3a. As a result, the right and left swinging members 6R and 6L exert equal tension on the magnetic attraction member 9 when the energization is off.

  The energization control to the swing member 6 is performed by the energization device 12 shown in FIG. This energization device 12 constitutes a part of a drive mechanism 24 for swinging the distal end portion 3 b of the movable optical fiber 3, and has three electric wires 13, 14, 15. , 15 are connected to electric wires 16, 17, 18 connected to the left and right thin film members 10, 10 and the central contact member 11C, respectively, as shown in FIG.

  The energization device 12 includes a power source 19 (battery), a changeover switch 20, and a return spring 21, and when the switch 20 is connected to a contact 22R on the right side (upper side in the figure), the right swing member 6R (upper side in the figure). When the switch 20 is connected to the contact point 22L on the left side (lower side in the figure), the left swing member 6L (lower side in the figure) is energized. Thereby, the front-end | tip part 3b of the movable optical fiber 3 can be swung to the left and right.

  Here, the return spring 21 is provided with the right swing member 6R or the left swing member while the switch 20 is pressed against the right contact 22R or the left contact 22L (for example, for a moment of about 0.2 to 0.4 seconds). 6L is energized, and then the function of cutting off the energization is exhibited.

  That is, the switch 20 is once separated from the contacts 22R, 22L by the spring force of the return spring 21 after being brought into contact with the contacts 22R, 22L, and cuts off the energization. For this reason, the tip portion 3b tries to return to the linear state (neutral state) by its own elastic force, but the swinging state of the tip portion 3b is maintained by the latch mechanism 8.

  As shown in FIGS. 1 to 3, the latch mechanism 8 includes a magnetic attraction member 9 made of a magnetic material such as a nickel pipe inserted and fixed to the distal end portion 3b of the movable optical fiber 3, and the intermediate recess 5cz (FIG. 3). And a magnet (permanent magnet) 23 mounted on each of them.

  The pipe length of the suction member 9 is preferably as long as possible as long as it does not interfere with the front stopper 7F and the rear stopper 7R. This is because the swinging force of the swing member 6 can be transmitted to the distal end portion 3b with a wide transmission area, and stress concentration can be avoided. However, the magnetic attraction member 9 does not necessarily need to be long and is not limited to a pipe shape.

  Further, as shown in FIG. 3, the magnets 23 are arranged symmetrically with respect to the vertical line L, and apply a magnetic force to the magnetic attraction member 9 equally on the left and right.

  According to the swinging member 6 and the latch mechanism 8 described above, the magnetic attraction member 9 inserted and fixed to the distal end portion 3b can be seen from the tension of the right and left swinging members 6R and 6L, Under a balance with the magnetic force of the magnets 23 and 23, when the swinging member 6 is not energized, it is positioned on the vertical line L (neutral position) and is floatingly supported apart from the bottom surface of the central convex portion 5cx. Since the suction member 9 is floated in this way, it is possible to prevent frictional resistance due to the suction member 9 rubbing against the bottom surface of the central convex portion 5cx when the distal end portion 3b of the movable optical fiber 3 is swung. The state where the suction member 9 is in the neutral position does not actually exist as described above.

  As is clear from FIG. 3, the magnets 23 are respectively positioned below the magnetic attraction member 9, and always attract the member 9 obliquely downward, and the member 9 is in the third recess when swinging. It prevents the dance from going up from 5c. That is, the magnetic attracting member 9, the right and left swinging members 6R, 6L are not only housed in the third recess 5c in a static state and below the upper surface 2a of the substrate 2, but also movable optical fibers. Even at the time of switching in which the tip 3 b of the head 3 is swung, it does not dance above the upper surface 2 a of the substrate 2. Therefore, these members 9, 6 </ b> R, and 6 </ b> L do not interfere with the cover provided so as to cover the recess 5.

  Now, in a schematic neutral state or in a state where the tip 3b is swung to the left, if only the right swing member 6R is energized, the right swing member 6R contracts and the tip 3b is swung to the right. . At this time, since the right swing member 6R is formed in a coil shape, it can easily and efficiently contract the entire length due to energization. Further, although the left swing member 6L is stretched, the left swing member 6L is also formed in a coil shape, so that it is easily stretched and does not become a swing resistance of the tip portion 3b.

  Once the tip 3b is swung to the right, the right magnet 23 attracts the magnetic attracting member 9 by the magnetic force, so that the swinging state of the tip 3b is maintained even if the right swinging member 6R is turned off. Can be maintained. Thereby, the power consumption for the swing of the front-end | tip part 3b can be suppressed as much as possible. Similarly, when the tip 3b is swung to the left, similarly, if the left swing member 6L is energized, the tip 3b is swung to the left, and the state is maintained even when the power is turned off. It is.

  As shown in FIGS. 1 and 2, on the left and right sides of the tip 3b of the movable optical fiber 3, the center of the tip 3b is set to the center of the stationary optical fibers 4R and 4L by limiting the swing amount of the tip 3b. A stopper 7 is provided as an alignment mechanism 25 for matching. The stopper 7 includes a front stopper 7 </ b> F and a rear stopper 7 </ b> R that are arranged at a predetermined interval along the longitudinal direction of the movable optical fiber 3.

  As shown in FIG. 7, the front stopper 7 </ b> F includes a pair of rib-like stopper plates that are disposed symmetrically in the third recess 5 c with the tip 3 b interposed therebetween. The stopper plate has an abutment surface 7Fx with which the swung tip 3b abuts, and the abutment surface 7Fx is formed to be orthogonal to the juxtaposed surface and the juxtaposition direction of the stationary optical fibers 4R and 4L. Has been. The contact surface 7Fx is formed such that the end surface 3b is concentrically opposed to the end surface of the end portion of the stationary optical fiber 4R or 4L when the distal end portion 3b contacts the contact surface 7Fx. Is set. Thereby, the center (core) of the front-end | tip part 3b and the center (core) of the edge part of the stationary optical fiber 4R or 4L can be concentrically opposed.

  The front stopper 7F includes a mounting plate on which the tip portion 3b is mounted. The mounting plate has a mounting surface 7Fy on which the tip 3b of the movable optical fiber 3 is mounted, and this mounting surface 7Fy has the same height (depth) as the bottom 5bx of the second recess 5b shown in FIG. A). Thereby, when the tip 3b is placed on the placement surface 7Fy, there is no difference in height between the tip 3b and the ends of the stationary optical fibers 4R and 4L, and the tip 3b is swung when the tip 3b is swung. The concentric opposition between the center (core) of the part 3b and the center (core) of the end of the stationary optical fiber 4R or 4L can be ensured.

  Moreover, the mounting surface 7Fy shown in FIG. 7 is formed in parallel with the juxtaposed direction in the juxtaposed surface of the stationary optical fibers 4R and 4L, and is a smooth plane. Thereby, when the front-end | tip part 3b mounted in this mounting surface 7Fy is swung, the smooth swing without a catch is ensured. The placement surface 7Fy has the same width as the bottom 5cx (see FIG. 5) of the second recess 5c.

  As shown in FIGS. 1 and 2, the rear stopper 7 </ b> R includes a side surface of a stepped portion that connects the second recess 5 b and the third recess 5 c. The width between the side surfaces of the stepped portion (that is, the width of the second recess 5b) is set equal to the width between the contact surfaces 7Fx of the front stopper 7F shown in FIG.

  By such a stopper 7 consisting of a front stopper 7F and a rear stopper 7R, the tip 3b abuts against the front stopper 7F and the rear stopper 7R when the head is swung, and its axis is the stationary optical fiber 4L, 4R. It is possible to form a parallel state that coincides with the axial center of each other.

  In the present embodiment, the movable optical fiber 3 is the transmission side and the stationary optical fibers 4R and 4L are the reception side. Conversely, the movable optical fiber 3 is the reception side and the stationary optical fibers 4R and 4L are the transmission side. Also good.

  The operation (action) of the optical fiber switch 1 according to the present embodiment configured as described above will be described.

  For example, in FIG. 1, in order to switch the connection between the movable optical fiber 3 and the right stationary optical fiber 4R to the left stationary optical fiber 4L, the switch 20 shown in FIG. 8 is changed from the right contact 22R to the left contact 22L. Then, while the switch 20 is in pressure contact with the contact 22L, the left swing member 6L is energized to generate heat and contract.

  Due to this contraction force, the magnetic attracting member 9 is attracted to the left stationary optical fiber 4L side, then enters the magnetic field of the left magnet 23, and the magnetic attracting member 9 is attracted to the magnet 23 by the magnetic force, and the distal end portion 3b of the movable optical fiber 3 is moved. The movement is stopped by contacting the front stopper 7F and the rear stopper 7R. As a result, the end surface of the distal end portion 3b of the movable optical fiber 3 faces the end surface of the left stationary optical fiber 4L, and switching is achieved.

  At the time of switching, the energization to the left swing member 6L is cut off by the return spring 21 shown in FIG. 8, and there is no wasteful power consumption. In this state, the attractive force of the magnet 23 constituting the latch mechanism 8 As a result, the magnetic attraction member 9 is attracted, and the swinging state of the tip 3b is maintained.

  At the time of the switching, the switching can be performed in an instant with almost no time delay. This is because the shape memory alloy-made swinging member 6 is mounted on the distal end portion 3b at a substantially right angle so as to cross the movable optical fiber 3, so that the shape restoring force of the shape memory alloy is substantially perpendicular to the distal end portion 3b. It is because it can be made to act directly from (lateral direction). Further, since the first recess 5a is formed at the end of the substrate 2, it is possible to earn as much as possible the length of the arm of the bending moment from the root 3a to the tip 3b where the shape restoring force acts. This is because the shape restoring force of the shape memory alloy can be effectively taken out as a power source for swinging the tip 3b.

  Further, when the distal end portion 3b of the movable optical fiber 3 is maintained in a swinging state after the switching is achieved, the distal end portion 3b can be maintained in a horizontal and parallel state by the magnet 23 and the stopper 7, so that the end surface of the distal end portion 3b And the opposite surfaces of the stationary optical fibers 4R and 4L are reliably secured. Therefore, leakage of transmitted light energy can be reduced.

  Specifically, the magnets 23 and 23 are disposed between the front stopper 7F and the rear stopper 7R, and the magnetic attraction member 9 is also disposed between the front stopper 7F and the rear stopper 7R. The tip 3b can be pressed evenly against the front stopper 7F and the rear stopper 7R, and the tip 3b can be held horizontally and parallel to the stationary optical fibers 4R and 4L. Therefore, the center (core) of the tip 3b can be appropriately made to be relative to the centers (core) of the stationary optical fibers 4L and 4R, and the leakage of transmitted light energy can be reduced.

  Further, the magnetic attraction member 9 and the swinging member 6 are arranged at an intermediate position between the front stopper 7F and the rear stopper 7R, thereby further equalizing the pressing force of the front end portion 3b against the front stopper 7F and the rear stopper 7R. Can be achieved.

  As described above, when the swinging member 6 is energized, the movable optical fiber 3 has its middle portion 3c elastically curved outward in the width direction of the substrate 2 with the root portion 3a as a fulcrum, and the tip portion 3b pushes the rear stopper 7R. As a fulcrum, it is elastically curved in the opposite direction (inward in the width direction), the tip 3b moves in parallel between the rear stopper 7R and the front stopper 7F, and the latch mechanism 8 and the stopper 7 The end face faces the end face of the stationary optical fiber 4R or 4L. Therefore, leakage of transmitted light energy can be reduced.

  Further, unlike the prior art, there is no need for an unrealistic assembling operation in which shape memory alloy wires are bonded along the upper and lower surfaces of the movable optical fiber 3, and the connection between the swinging member 6 and the movable optical fiber 3 is not required. Is indirect via the magnetic attraction member 9, so that the connection is easy and the movable optical fiber 3 is not damaged during the connection.

  In addition, since the substrate 2 is provided with a recess 5, and the movable optical fiber 3, the stationary optical fibers 4R and 4L, the swinging member 6, the stopper 7 and the latch mechanism 8 are accommodated in the recess 5, the recess is formed with a flat cover. By covering 5, the inside of the recess 5 can be easily sealed. As a result, the swinging member 6 does not receive an external force, and the optical fiber switch 1 can be protected from humidity and dust. For example, it is possible to prevent the swinging member 6 from being deformed and damaged by an external force, and to prevent water droplets due to dust or humidity from adhering to the connection end surfaces of the optical fibers 3, 4 </ b> R, 4 </ b> L. Therefore, there is no trouble in the installation place of the optical fiber switch 1, and the freedom degree of an installation place spreads.

  Further, since the rear stopper 7R uses a stepped portion between the second concave portion 5b and the third concave portion 5c, it is not necessary to provide this again. Incidentally, the concave portion 5 (first to fourth concave portions 5a to 5d) can be processed very easily and very precisely by a micromachining technique.

  A modification is shown in FIG.

  In this modification, the shape of the fourth recess 5d shown in FIG. 1 is different from that of the above-described embodiment, and the other configurations are substantially the same. As shown in FIG. 9, the width of the groove of the fourth recess 5d ′ is set to be slightly wider than the width of two stationary optical fibers 4R and 4L arranged side by side. A predetermined gap c is set between them. Thus, it is possible to prevent so-called crosstalk in which light leaking from one stationary optical fiber 4R (4L) enters the other stationary optical fiber 4L (4R) and becomes noise. Of course, the width of the stopper 7 in the left-right direction (the swinging direction of the tip 3b) is slightly increased in correspondence with the groove width of the fourth recess 5d '.

  Another modification is shown in FIG.

  In this modification, a spacer member s having a light shielding property is interposed between the two stationary optical fibers 4R and 4L of the modification shown in FIG. According to this modification, the crosstalk can be completely prevented.

  The present invention is not limited to the above embodiment. For example, the swinging member 6 is not limited to crossing perpendicularly to the distal end portion 3b (magnetic attraction member 9) of the movable optical fiber, but may be crossed obliquely, or may be crossed in an X shape. There may be. Further, the swinging member 6 may be arranged like an isosceles triangle, and the tip 3b (magnetic attraction member 9) may be locked to the apex thereof.

  Further, as shown in FIG. 3, the magnetic attraction member 9 is not limited to the one that is floated in the recess 5 (third recess 5 c), and does not prevent contact with the bottom surface of the recess 5.

  Further, the swinging member 6 is constituted by a single shape memory alloy member formed in a coil shape, and is normally contracted so that the tip 3b is swung to one side (for example, the left side), and is energized to generate heat. Then, the tip 3b may be extended so as to swing to the other side (for example, the right side), or may have reverse characteristics. Thereby, the circuit of the electricity supply apparatus 12 can be simplified.

  Further, the swinging member 6 is not limited to a coil shape, and may be a curved line shape as long as the tip portion 3b can be swung by turning on and off the current.

It is a perspective view of the optical fiber switch concerning this embodiment. It is a top view of the said optical fiber switch. It is the III-III sectional view taken on the line of FIG. It is the IV-IV sectional view taken on the line of FIG. It is the VV sectional view taken on the line of FIG. It is the VI-VI sectional view taken on the line of FIG. It is the VII-VII sectional view taken on the line of FIG. It is an electric circuit diagram of an electricity supply apparatus. It is a figure which shows the modification of a 4th recessed part, and is a figure corresponded to the VI-VI sectional view taken on the line of FIG. It is a figure which shows the modification by 4th recessed part, and is a figure equivalent to the VI-VI sectional view taken on the line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical fiber switch 2 Switch board 3 Movable optical fiber 3a A part (root part)
3b Tip 3c Intermediate 4R Static optical fiber (right side)
4L stationary optical fiber (left side)
6 Swing member 6R Right swing member 6L Left swing member 7 Stopper 7F Front stopper 7R Rear stopper 8 Latch mechanism 9 Magnetic attraction member 23 Magnet 24 Drive mechanism 25 Positioning mechanism

Claims (4)

A switch substrate, a movable optical fiber that is partially fixed to the switch substrate and capable of swinging the tip, and two stationary optical fibers that are arranged in parallel on the switch substrate so as to face the tip of the movable optical fiber A fiber optic switch that optically connects the movable optical fiber to one of two stationary optical fibers by swinging the tip, wherein one end is fixed to the tip and the other is on the right side of the tip A right-hand swing member made of a shape memory alloy fixed to one switch board, and a left-hand swing member made of a shape memory alloy having one end fixed to the tip part and the other end fixed to the left switch board of the tip part. A drive mechanism having a member and an energization device that energizes one of the right-hand swing member and the left-hand swing member to generate heat;
The switch board has a front stopper and a rear stopper provided at predetermined intervals in the longitudinal direction of the movable optical fiber so that the swing member is sandwiched between the switch board, and by limiting the swing amount of the tip part, An alignment mechanism that aligns the center with the center of the stationary optical fiber;
A pair of magnets disposed on both sides of the tip portion between the front stopper and the rear stopper on the switch board, and the right swing member and the left neck mounted on the tip portion A latch mechanism having a magnetic attraction member made of a magnetic material to which the swing member is fixed, and holding the tip in a swinging state;
An optical fiber switch comprising:   2. The optical fiber switch according to claim 1, wherein the right swing member and the left swing member are integrally formed as a single member.   The optical fiber switch according to claim 1 or 2, wherein the right swing member and the left swing member are formed in a coil shape. 4. The optical fiber switch according to claim 1, wherein the switch board is provided with a recess for receiving the swinging member, stopper, latch mechanism, movable and stationary optical fibers.

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