Optical connector cleaning tool

An optical connector cleaning tool includes a holder, cleaner, and cap. The holder includes, a cylindrical slider, a cylindrical body which is rotatable and movable in the axial direction with respect to the slider, and a slider return spring which biases the body forward to return the slider to the initial position. The slider has a pair of elastic pieces having guide projections. In the outer circumferential surface of the body, spiral grooves with which the guide projections engage are formed within the angular range of 360°. When the slider moves forward, the body rotates by the cam action of the guide projections and spiral grooves. The cleaner includes, a cleaning thread accommodated in a rotary pod, a supply reel, a take-up reel, and a cleaning pin, and is connected to the body.

This is a non-provisional application claiming the benefit of International application number PCT/JP2009/055421 filed Mar. 19, 2009.

TECHNICAL FIELD

The present invention relates to an optical connector cleaning tool to be used to clean the connection surface of an optical connector.

BACKGROUND ART

Optical connectors for use in optical communication splice optical fibers as they butt each other. If the ferrule end faces of the optical connectors, particularly, those end faces (connection surfaces) of the optical fibers which are leveled with the coupling end faces of the connectors are contaminated, or deposits such as fats and oils or dust stick to the end faces, the insertion loss of the optical connectors increases, and their return loss decreases. Since optical signals cannot normally be transmitted any longer, it is necessary to remove the contamination or deposits by cleaning the connection surfaces as needed.

Conventionally, as an optical connector cleaning tool for cleaning the connection surface of an optical connector as described above, a stick type cleaning tool C including a shaft portion A and cotton portion B as shown inFIG. 28is used when the optical connector is a female connector because the connection surface of an optical fiber does not protrude outside a connector main body. That is, when performing cleaning by using the cleaning tool C, an operator cleans the ferrule end face as a surface to be cleaned by inserting the cotton portion B into an optical connector, bringing the cotton portion B into contact with the ferrule end face, and rotating the shaft portion A in this state.

On the other hand, when an optical connector is a male optical connector, the optical connector is cleaned by using a tape type, sheet type, or thread type cleaning tool disclosed in, e.g., Japanese Patent Laid-Open Nos. 2001-246343, 2005-17756, or 2002-090576, or WO2004/073896.

Accordingly, it is normally necessary to prepare two types of cleaning tools for male and female optical connectors in accordance with connectors. As disclosed in, e.g., Japanese Patent Laid-Open No. 9-285766, however, a combination optical connector cleaning device capable of cleaning both male and female optical connectors has also been put to practical use.

DISCLOSURE OF INVENTION

Problem that the Invention is to Solve

Unfortunately, the conventional optical connector cleaning tools disclosed in Japanese Patent Laid-Open Nos. 9-285766, 2001-246343, and 2002-090576 and WO2004/073896 all require motors, power supplies, gears, and the like, and this increases the number of parts and the cost.

The present invention has been made to solve the above-mentioned conventional problem, and has as its object to provide an optical connector cleaning tool capable of decreasing the number of parts by using a simple structure and requiring no driving source.

Means of Solving the Problem

To achieve the above object, the present invention includes a holder, and a cleaner which is rotatably attached to the holder and cleans a connection surface of an optical connector by a cleaning thread, the holder including a cylindrical slider including an elastic piece having a guide projection on a circumferential wall, a cylindrical body having, in an outer circumferential surface, a spiral groove with which the guide projection engages, and installed in the slider such that the cylindrical body is rotatable and movable forward and backward, a slider return spring which returns the slider to an initial position, and a shaft accommodated in the slider, the cleaner including a rotary pod connected to the body, a supply reel around which the cleaning thread is wound, a take-up reel which has one end connected to the shaft and takes up a used cleaning thread, and a cleaning pin which brings the cleaning tread into contact with the connection surface of the optical connector, and the cleaning pin including a thread support portion having, on a distal end face, a thread support surface which supports the cleaning thread, and protruding from the rotary pod, wherein the rotary pod gives tension to the cleaning thread by rotating together with the body during cleaning, thereby supplying an unused cleaning thread from the supply reel, and taking up a used cleaning thread to the take-up reel.

Effects of the Invention

In the present invention, when an operator holds the slider with hand, brings the distal end of the cleaning pin into contact with the connection surface (ferrule end face) of an optical connector, and moves the slider forward against the slider return spring in this state, the guide projection moves in the spiral groove and presses the groove wall, thereby converting the linear motion of the slider into the rotation of the body by the cam action. When the body rotates, the rotary pod and cleaning pin rotate together. Therefore, the cleaning thread guided to the distal end face of the cleaning pin cleans the connection surface of the optical connector. Since the distal end face of the cleaning pin is pressed against the connection surface of the optical connector, the position of the distal end face remains unchanged even when the body, rotary pod, and cleaning pin rotate, and only the slider moves forward by a predetermined distance to rotate the body, rotary pod, and cleaning pin through a predetermined angle. The rotary pod and body give tension to the cleaning thread by rotating around the supply reel and take-up reel. Accordingly, the cleaning thread is supplied from the supply reel and guided to the distal end face of the cleaning pin. After cleaning the ferrule end face, the cleaning thread is guided to the take-up reel and taken up. This makes it possible to clean the ferrule end face by an unused cleaning thread whenever performing cleaning. When the force holding the slider weakens after the cleaning of the optical connector by the cleaning thread is complete or during the cleaning, the slider moves backward and returns to the initial position by the counterforce of the slider return spring.

The spiral groove of the body and the guide projection of the slider convert the linear motion of the slider into the rotation of the body by engaging with each other. Since this obviates the need for a motor, gear mechanism, and the like, the structure is simple, and the number of parts can be reduced. This makes it possible to reduce the cost. Also, the cleaning thread does not easily break compared to a tape, and this facilitates handling the cleaning tool. Furthermore, the slider return spring biases the body in a direction to project from the slider. Therefore, the body cannot freely rotate except when the slider is in operation, so a slack of the cleaning thread can be prevented.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be explained in detail below based on embodiments shown in the drawings.

Referring toFIGS. 1 to 5, an optical connector cleaning tool1includes a holder2, a cleaner5attached to the holder2, and a cap6detachably attached to the distal end of the cleaner5, and forms a cleaning tool capable of cleaning both a female connector3and male connector90.

The female connector3integrally includes a receptacle7in which the male connector90is to be fitted, and the receptacle7protects an end face (connection surface)4aof a ferrule4.

As shown inFIG. 4, the holder2includes, e.g., an almost cylindrical slider10having two open ends, a lid11that closes the rear-end opening of the slider10, a body12accommodated in the slider10, a slider return spring13that biases the body12forward to return the slider10to the initial position, and a shaft14.

The slider10is a portion to be held by an operator during cleaning, and is a plastic molded product. Two elastic pieces16are formed back to back near the front end of the circumferential wall so as to be spaced apart by 180° in the circumferential direction. Each elastic piece16is formed into a tongue-like shape elongated in the axial direction of the slider10by a U-shaped hole15. The front end of the elastic piece16is connected to the slider10, and the rear end and two side edges of the elastic piece16are disconnected from the slider10by the U-shaped hole15. Also, the elastic pieces16can elastically deform in the direction of thickness. As shown inFIG. 2, a columnar guide projection17is integrally formed at the distal end portion of the inner surface of each elastic piece16. In a normal state, the guide projection17projects inside the slider10. On the other hand, in the vicinity of the rear-end opening of the circumferential wall of the slider10, two small engaging holes19for locking the lid11are formed apart by 180° in the circumferential direction.

The lid11is formed into a cylindrical shape having an outer diameter almost equal to the inner diameter of the slider10. The lid11is fitted in the rear-end opening of the slider10, and detachably attached to the slider10by engaging projections21formed on the outer circumferential surface with the engaging holes19of the slider10. The shaft14integrally projects from the center of the inner surface of the lid11with a boss portion22being interposed between them. The shaft14has a hexagonal sectional shape, and has a distal end that extends near the front-end opening of the slider10. Note that the sectional shape of the shaft14is not limited to a hexagon and can be any shape, provided that the sectional shape can prevent the rotation of a take-up reel43(to be described later).

Referring toFIG. 4, the body12is a cylindrical member formed by injection molding of a synthetic resin and having two open ends, and the outer diameter of the cylinder is slightly smaller than the inner diameter of the slider10. The rear end portion of the body12is accommodated in the slider10so as to be rotatable and movable forward and backward. A front end portion12aof the body12forms a connecting portion of a rotary pod40(to be described later). The outer circumferential surface forms a tapered portion inclined at a predetermined angle, and has four slits23that facilitate attaching the rotary pod40by decreasing the diameter when fitting the rotary pod40. The slits23are formed to be elongated in the axial direction of the body12, and open in the front end face of the body12.

The outer circumferential surface of the body12has two spiral grooves25and26and two straight grooves27and28. The spiral grooves25and26and the guide projections17formed on the elastic pieces16of the slider10form a rotating mechanism that rotates the cleaner5by converting the linear motion of the slider10into the rotation of the body2. That is, the body2rotates when the guide projections17linearly move along the spiral grooves25and26. Also, when the body12is in the initial position, the guide projections17are positioned at start ends25aand26aof the spiral grooves25and26. In this state, the guide projections17and spiral grooves25and26form a removal preventing mechanism that prevents the removal of the body12from the slider10.

The two spiral grooves25and26are formed within the angular range of 360° at an interval of 180° in the circumferential direction of the body12. Therefore, the body12maximally rotates once when the slider10moves forward. Since the spiral grooves25and26are clockwise grooves, the body12rotates clockwise as the guide projections17push the left-side walls of the spiral grooves25and26when the slider10is advanced against the slider return spring13. However, it is also possible to form counterclockwise grooves, and rotate the body12counterclockwise.

On the other hand, the straight grooves27and28are used as passages through which the guide projections17pass when the slider10is returned to the initial position by the slider return spring13after the slider10is moved forward by a maximum stroke. The straight grooves27and28are grooves elongated in the axial direction of the body12, and formed apart by 180° in the circumferential direction. Of the straight grooves27and28, the straight groove27is a straight groove connecting the start end25aand a terminal end25bof the spiral groove25, and has a center that intersects and communicates with the center of the spiral groove26. Also, the bottom surface of a groove portion27A from a start end27aof the straight groove27to the spiral groove26and that of a groove portion27B from the center to a terminal end27bof the straight groove27do not have any constant depth, but are formed as slopes inclined such that the depth gradually increases toward the front end of the body2. The start ends25aand26aof the spiral grooves25and26are at the rear end of the body12, and the terminal end25band a terminal end26bof the spiral grooves25and26are at the front end of the body12. Likewise, the straight groove28is a straight groove connecting the start end26aand terminal end26bof the spiral groove26, and has a center that intersects and communicates with the center of the spiral groove25(seeFIG. 1). Also, similar to the straight groove27, the bottom surface of a groove portion28A from the start end28aof the straight groove28to the spiral groove26and that of a groove portion28B from the center to a terminal end28bdo not have any constant depth, but are formed as slopes inclined such that the depth gradually increases toward the front end of the body12.

The two straight grooves27and28as described above are formed and their bottom surfaces are formed as slopes in order to facilitate removing the guide projections17from the straight grooves27and28when removing the body12from the slider10. That is, if the depth of the straight grooves27and28is constant and large, the guide projections17cannot be retreated from the straight grooves27and28even when moving the guide projections17from the spiral grooves25and26to the straight grooves27and28by rotating the body12, because the guide projections17abut against the groove walls of the straight grooves27and28and this makes it impossible to elastically deform the elastic pieces16outward. On the other hand, when the bottom surfaces of the straight grooves27and28are formed as slopes, the guide projections17readily climb over the straight grooves27and28when the body12is rotated with the guide projections17being positioned in the shallowest portions of the bottom surfaces of the straight grooves27and28, i.e., at the start ends27aand28aor in the centers of the straight grooves27and28. Accordingly, the elastic pieces16elastically deform outward, and the guide projections17can retreat from the straight grooves27and28. In other words, the guide projections17can be disengaged from the straight grooves27and28. Therefore, the slider10and body12can be separated by spring out the body12from the slider10by the spring force of the slider return spring13, or pulling out the body12from the slider10by hand. Note that when connecting the body12to the slider10, it is only necessary to forcedly press the rear end of the body12into the slider10against the slider return spring13, and elastically deform the elastic pieces16outward by pushing the guide projections17by the rear end of the body12, thereby engaging the guide projections17with the spiral grooves25and26.

A pair of engaging holes30and a long hole31are formed in a front end portion12aof the body12. The pair of engaging holes30are holes for detachably locking the rotary pod40(to be described later), and formed apart by 180° in the circumferential direction of the body12so as to face each other. The long hole31is a hole elongated in the axial direction of the body12, and has a front end that opens in the front-end opening of the body12.

Referring toFIG. 3, the inner circumferential surface of the body12has a guide groove32and spring receiving plate33. The guide groove32is formed behind the long hole31such that their central lines in the widthwise direction are aligned, i.e., such that the guide groove32and long hole31are formed on the same straight line. The groove width of the guide groove32is set larger than the hole width of the long hole31. The spring receiving plate33is a circular disk formed behind the guide groove32and perpendicular to the axis of the body12. The spring receiving plate33has, in its center, an insertion hole34through which a rear-end shaft43E of the take-up reel43(to be described later) extends. The front end of the slider return spring13is in tight contact with the back surface of the spring receiving plate33.

The slider return spring13is a spring that returns the slider10to the initial position, and biases the body12in a direction to protrude from the slider10, i.e., biases the body12forward. The slider return spring13is a compression coil spring, and incorporated into the slider10so as to be compressed by a predetermined amount.

Referring toFIG. 5, the cleaner5includes, e.g., the rotary pod40, a supply reel42accommodated in the rotary pod40, a cleaning thread41wound around the supply reel42, the take-up reel43for taking up the cleaning thread41, a cleaning pin44that rotates together with the rotary pod40during cleaning, and a thread swinging member45that swings, in the axial direction of the take-up reel43, a used cleaning thread41to be taken up to the take-up reel43.

The rotary pod40is integrally formed by injection molding of a synthetic resin, and includes a cylindrical pod main body40A having a partially notched circumferential wall, a conical portion40B integrally connected to the front end of the pod main body40A, and a cylindrical portion40C integrally projecting from the front end of the conical portion40B. The pod main body40A is made up of three cylinders having the same inner diameter over the entire length and different outer diameters, i.e., a large-diameter cylinder46A, medium-diameter cylinder46B, and small-diameter cylinder46C that decrease the diameter from the front end to the rear end. A step47formed in the boundary between the large-diameter cylinder46A and medium-diameter cylinder46B forms a contact surface that comes in contact with the distal end face of the body12and positions the rotary pod40with respect to the body12. The medium-diameter cylinder46B is inserted together with the small-diameter cylinder46C into the front end portion of the body12, and has a thread extracting hole50and long hole51spaced apart by 180° in the circumferential direction. The thread extracting hole50is formed to extend from the front end of the medium-diameter cylinder46B to a rear end53aof the small-diameter cylinder46C, and has a rear end that opens in the rear end53aof the small-diameter cylinder46C. The long hole51forms a guide hole57(FIG. 3) together with the long hole31of the body12. The guide hole57extends over the entire length of the medium-diameter cylinder46B and small-diameter cylinder46C, and has a rear end that opens in the rear end53aof the small-diameter cylinder46C. In addition, on the outer circumferential surface of the medium-diameter cylinder46B, a pair of locking projections55for locking the rotary pod40to the body12are integrally formed apart by 180° in the circumferential direction. The locking projections55are wedge-shaped projections, and detachably connect the rotary pod40to the front end portion12aof the body12by engaging with the engaging holes30(FIG. 4) of the body12.

The small-diameter cylinder46C is a portion to be connected together with the meddle portion46B to the body12, and has an extension46D integrally extending from a part of the rear end. As shown in FIG.5, the right end portion of the extension46D is positioned behind the thread extracting hole50. Also, the extension46D has a thread insertion hole58into which the used cleaning thread41guided from the cleaning pin44is to be inserted. The edge of the thread insertion hole58forms a fulcrum for swinging the used cleaning thread41in the axial direction of the take-up reel43when winding the used cleaning thread41around the take-up reel43. In addition, the small-diameter cylinder46C has a reel locking piece59(FIGS. 2 and 5) for positioning the take-up reel43to regulate the movement in the axial direction, thereby preventing the removal of the take-up reel43from the rotary pod40. The reel locking piece59is a cantilevered tongue-like member formed at the rear-end edge of the small-diameter cylinder46C. A portion connecting to the small-diameter cylinder46C forms a flexible hinge, and a free end portion is normally offset inside the small-diameter cylinder46C. The reel locking piece59having this structure stops a front-side flange43B of the take-up reel43(FIG. 2) from behind.

The cylindrical portion40C of the rotary pod40is a portion that accommodates the cleaning pin44such that it cannot rotate, and protrudes a thread support portion44B of the cleaning pin44forward. The cylindrical portion40C has a hexagonal fitting hole60that is a through hole.

The cleaning thread41is, e.g., a thread formed by intertwining a large number of very thin fibers (e.g., polyester) of about 0.1 to 0.5 denier, and has a thickness almost equal to the diameter (1.25 or 2.5 mmφ) of the ferrule4(91) shown inFIG. 1. Also, the cleaning thread41is wound around the supply reel42such that the winding thickness is uniform in the axial direction of the reel42. To make the winding thickness of the cleaning thread41uniform in the axial direction of the reel42, the cleaning thread41is wound around the supply reel42so as to be regularly reciprocated in the axial direction of the supply reel42. That is, after being wound from one end to the other of the supply reel42, the cleaning thread41is wound from the other end to one end. The cleaning thread41can be wound to have a uniform thickness by repeating this operation.

The supply reel42includes a cylinder42A around which the cleaning thread41is wound, and a pair of flanges42B and42C integrally formed at the two end portions of the cylinder42A. The supply reel42is rotatably axially supported by a front-end shaft43D of the take-up reel43. When the supply reel42having this structure is incorporated together with the take-up reel43into the rotary pod40, the front-side flange42B abuts against an inner wall40a(FIG. 3) of the rotary pod40, and the rear-side flange42C abuts against the front-side flange43B of the take-up reel43. This regulates the movement in the axial direction of the supply reel42.

The take-up reel43includes a cylinder43A for taking up the used cleaning thread41, a pair of the flange43B and a flange43C integrally formed at the two ends of the cylinder43A, the front-end shaft43D extending before the flange43B, and the rear-end shaft43E integrally protruding from the rear end of the flange43C. The front-end shaft43D is inserted into the central hole of the supply reel42, thereby rotatably axially supporting the supply reel42. The distal end portion of the front-end shaft43D projects before the supply reel42, and forms a bearing63for rotatably axially supporting the rear end of the cleaning pin44. The rear-end shaft43E has an outer diameter larger than that of the front-end shaft43D, and has a hexagonal engaging hole64in which the distal end portion of the shaft14is to be fitted. Therefore, the take-up reel43is detachably connected to the shaft14so as not to be rotatable.

Also, when the take-up reel43is incorporated together with the supply reel42and cleaning pin44into the rotary pod40, the front-side flange43B is stopped by the reel locking piece59(FIG. 2) of the rotary pod40, and inhibited from removing from the rotary pod40. When assembling the optical connector cleaning tool1, the supply reel42and cleaning pin44are incorporated into the rotary pod40, and the take-up reel43is incorporated into the body12. After that, the medium-diameter cylinder46B and small-diameter cylinder46C of the rotary pod40are inserted into the body12, and the engaging projections55are engaged with the engaging holes30, thereby integrally connecting the rotary pod40and body12. In addition, the rear end portion of the body12is inserted into the slider10, the guide projections17are engaged with the spiral grooves25and26, and the rear-end shaft43E of the take-up reel43is relatively slidably fitted on the shaft14, thereby connecting the body12and slider10. In this manner, the assembly of the optical connector cleaning tool1is complete.

When pulling out the take-up reel43from the rotary pod40, an operator can easily pull out the take-up reel43from the rotary pod40by elastically deforming the free end portion of the reel locking piece59outward by hand, thereby disengaging the flange43B of the take-up reel43from the reel locking piece59.

Referring toFIG. 5, the cleaning pin44includes a pin main body44A and the thread support portion44B. The pin main body44A is a hexagonal cylinder, and fitted in the fitting hole60of the cylindrical portion40C of the rotary pod40so that the rotation of the pin main body44A is regulated. In the rear end portion of the pin main body44A, two slits65into which the cleaning thread41is to be inserted are formed in the axial direction so as to be spaced apart by 180° in the circumferential direction. Also, on the rear end portion of the outer circumferential surface of the pin main body44A, two stoppers66(FIG. 2) for defining that amount of the pin main body44A which is to be inserted into the cylindrical portion40C are integrally formed at an interval of 180° in the circumferential direction. Each stopper66has a wedge shape.

The thread support portion44B of the cleaning pin44is formed into a columnar shape having an outer diameter (1.25 or 2.5 mmφ) almost equal to that of the ferrule4(91), and integrally projects from the front end of the pin main body44A. The distal end face of the thread support portion44B forms a thread support surface S for supporting the cleaning thread41. A thread supporting groove70is formed in the center of the thread support surface S, and has two ends that open in the outer circumferential surface (side surface) of the thread support portion44B. On the outer circumferential surface of the thread support portion44B, a thread extracting groove71and thread introducing groove72(FIG. 6) are formed apart by 180° in the circumferential direction of the thread support portion44B. The thread extracting groove71and thread introducing groove72have front ends positioned behind the thread supporting groove70, and rear ends that communicate with the interior of the pin main body44A.

The thread swinging member45is formed into a long and narrow plate by using a transparent material such as an acrylic resin, and slidably inserted into a guide hole57(FIG. 3) formed in the connecting portion of the body12and rotary pod40from inside these two members. The two ends of the thread swinging member45has a supply-reel-side hole80and take-up-reel-side hole81into which the cleaning thread41is to be inserted. The cleaning thread41supplied from the supply reel42is inserted into the supply-reel-side hole80, and the used cleaning thread41passed through the thread insertion hole58of the rotary pod40is inserted into the take-up-reel-side hole81. The cleaning thread41supplied from the supply reel42is passed through the supply-reel-side hole80of the thread swinging member45, guided into the cleaning pin44from the slit65in the rear end of the cleaning pin44, and supplied outside the cleaning pin44from the thread extracting groove71. Also, the cleaning thread41supplied from the thread extracting groove71is guided into the pin main body44again through the thread supporting groove70and thread introducing groove72of the cleaning pin44, and supplied outside from the rear-end opening of the pin main body44A. The cleaning thread41supplied from the cleaning pin44is further inserted into the thread insertion hole58of the rotary pod40and the take-up-reel-side hole81of the thread swinging member45, and taken up to the take-up reel43.

Referring toFIG. 6, the cap6is formed into a cylinder having two open ends. The inner diameter of a rear end portion into which the cylindrical portion40C of the rotary pod40is to be inserted is large, and that of a front end portion into which the thread support portion44B of the cleaning pin44is to be inserted is small. A hole85in the front end of the cap6forms a hole into which the connecting end portion of a ferrule91is inserted when cleaning the male connector90. When the optical connector cleaning tool1is not in use, the hole85is closed by a lid93. The lid93is integrally connected to the front end of the cap6by a thin foldable hinge94.

When assembling the holder2of the optical connector cleaning tool1having the above-mentioned structure, the lid11to which the shaft14is attached as described previously is fixed by being fitted in the rear-end opening of the slider10, and the slider return spring13is accommodated in the slider10. After that, the body12is incorporated into the slider10. To incorporate the body12into the slider10, the guide projections17are aligned with the spiral grooves25and26, and the body12is pressed into the slider10against the slider return spring13. When the body12is pressed into the slider10, the rear end of the body12abuts against the guide projections17, and elastically deforms the elastic pieces16outward. When the body12is further pressed into the slider10and the guide projections17are aligned with the spiral grooves25and26, the elastic pieces16elastically return. Consequently, the guide projections17engage with the start ends25aand26aof the spiral grooves25and26, thereby completing the assembly of the holder2.

When drawing out the body12from the slider10, the body12is pressed into the slider10against the slider return spring13as described above, thereby moving the projections17from the start ends25aand26aof the spiral grooves25and26to the start ends27aand28aof the straight grooves27and28. In this state, the elastic pieces16are elastically deformed outward by rotating the body12through a predetermined angle, thereby drawing out the guide projections17from the straight grooves27and28. After that, the body12is pulled out from the slider10.

When attaching the cleaner5to the holder2, the rotary pod40is fitted on the front end portion12aof the body12, the locking projections55of the rotary pod40are engaged with the engaging holes30of the body12, and the rear-end shaft43E of the take-up reel43is fitted on the shaft14.

When used up, the cleaning thread41must be replaced with a new cleaning thread. In this case, it is troublesome to pass the cleaning thread41through the cleaning pin44. Accordingly, it is desirable to remove the used cleaner5from the body12, and replace the used cleaner5with a new assembled cleaner5. When replacing the cleaner5, it is only necessary to remove the cleaner5from the body12by disengaging the engaging projections55from the engaging holes30, fit a new cleaner5on the front end portion12aof the body12and connect them by engaging the engaging projections55and engaging holes30, and connect the take-up reel43to the shaft14. Therefore, the cleaner5can simply and easily be replaced.

When cleaning the connection surface of the female optical connector3by using the optical connector cleaning tool1as described above, an operator holds the slider10and inserts the thread support portion44B of the cleaning pin44into the receptacle7to bring the cleaning thread41into contact with the connection surface4aof the ferrule4. That is, when the thread support portion44B is inserted into the receptacle7and the thread support surface S of the cleaning pin44is pushed against the connection surface4aof the ferrule4, the cleaning thread41in the thread supporting groove70formed in the thread support surface S comes in contact with the connection surface4a.

Then, the slider10held in this state is moved forward against the slider return spring13. When the slider10is moved forward, the guide projections17push the groove walls on the left side inFIG. 1of the spiral grooves25and26, so the body12rotates clockwise inFIG. 1. That is, the spiral grooves25and26form a female screw, and the guide projections17form a male screw. When the slider10moves forward, therefore, the cam action between the guide projections17and spiral grooves25and26rotates the body12. When the body12rotates, the rotary pod40also rotates together with the body12. When the rotary pod40rotates, the cleaning pin44also rotates together with the rotary pod40, and the cleaning thread41guided to the thread support surface S of the cleaning pin44cleans the connection surface4aof the ferrule4. When the slider10is moved forward by a maximum stroke in this state, the body12rotates once, and the cleaning pin44also rotates once. Consequently, the cleaning thread41cleans the whole of the connection surface4aof the ferrule4once from 0° to 180° and once from 180° to 360°, i.e., cleans the connection surface4atwice in total.

During the cleaning, the rotary pod40rotates around the supply reel42and take-up reel43, and gives tension to the cleaning thread41by integrally rotating the take-up reel43. As a consequence, an unused cleaning thread41wound around the supply reel42is forcedly supplied, and the cleaning thread41having cleaned the connection surface4ais taken up to the take-up reel43. Accordingly, it is possible to automatically supply the cleaning thread41from the supply reel42and take up the cleaning thread41to the take-up reel43by only moving the slider10forward, and use an unused pure cleaning thread41whenever performing cleaning. Furthermore, it is unnecessary to form any rotation transmitting mechanism such as a gear for transmitting rotation to the supply reel42and take-up reel43. This makes it possible to simplify the structure of the cleaning tool1and reduce the number of parts. In addition, when moved forward by a maximum stroke or stopped halfway, the slider10moves backward by the counterforce of the slider return spring13and returns to the initial position. Therefore, the optical connector3can repetitively be cleaned by rotating the cleaner5by moving the slider10forward again.

Also, the spiral grooves25and26formed in the outer circumferential surface of the body12and the guide projections17formed on the slider10construct a rotating mechanism that converts the linear motion of the slider10into the rotation of the cleaner5. Since this obviates the need for any driving device such as a motor, it is possible to simplify the structure and reduce the number of parts.

Furthermore, the optical connector cleaning tool1uses the thin thread41as a cleaning member. Since the thread41does not easily break compared to a tape, it is easy to handle the optical connector cleaning tool1.

If the body12idles, i.e., freely rotates, the cleaning thread41slacks, and a dirty thread already used in cleaning is rewound. Consequently, the slack of the thread causes a jam of the thread or an operation error, or cleaning is performed by reusing the used dirty cleaning thread. To prevent these accidents, in the optical connector cleaning tool1according to the present invention, the slider return spring13biases the body12forward to push the spiral grooves25and26against the guide projections17. Since this eliminates the possibility of idling of the body12, a slack of the cleaning thread41can reliably be prevented.

Also, the cleaner5is attached to the holder2so as to be replaceable. After the cleaning thread41is used up, therefore, the holder2can be reused by replacing the cleaner5with a new cleaner5.

Furthermore, the take-up reel43rotatably supports the supply reel42and cleaning pin44. Since this obviates the need for any special bearing member, the number of parts can further be reduced.

In the cleaner5, the cleaning thread41is extracted outside the cleaning pin44from inside the cleaning pin44through the thread feedout slit71and guided to the thread supporting groove70, and guided into the cleaning pin44again from the thread feedin slit72. Therefore, only a small part of the cleaning thread41is exposed outside from the cleaning pin44. This makes it possible to prevent the adhesion of dust or the like to an unused thread, and protect an unused thread from being contaminated by a touch with the hand. As a result, the cleaning thread41can be used in a clean state.

The cleaner5further includes the thread swinging member45. Accordingly, the used cleaning thread41can be swung in the axial direction of the take-up reel43and taken up to the cylinder43A of the take-up reel43, i.e., the cleaning thread41is not collectively taken up to one portion. More specifically, when the rotary pod40rotates during cleaning, the cleaning thread41wound around the supply reel42is supplied from it while the cleaning thread41is reciprocated in the axial direction of the reel42. In other words, the cleaning thread41is swung in the axial direction of the supply reel42. Therefore, the thread swinging member45reciprocates in the guide hole57formed in the connecting portion of the body12and rotary pod40by the tension of the cleaning thread41, and the used cleaning thread41is wound as it is swung in the axial direction of the take-up reel43. This prevents the cleaning thread41from being collectively taken up to one portion of the take-up reel41.

In addition, the swinging member45is made of a transparent material. This makes it possible to externally visually check the interior of the cleaner5, and readily confirm whether an unused cleaning thread41remains on the supply reel42.

Also, in the cleaner5, the used cleaning thread41extracted from the cleaning pin44is inserted into the thread insertion hole58formed in the rear end of the rotary pod40, and the cleaning thread41inserted into the thread insertion hole58is further inserted into the take-up-reel-side hole81of the thread swinging member45. After that, the cleaning thread41is guided to the take-up reel43. Therefore, the used cleaning thread41can further reliably be swung and taken up to the take-up reel43.

Furthermore, the cleaner5can protect the thread support surface S of the cleaning pin44against dust and the like by attaching the cap6to the thread support portion44B of the cleaning pin44. In addition, the use of the cap6makes it possible to clean a connection surface91aof the male optical connector90as shown inFIG. 6. That is, the lid93is opened, and the ferrule91of the male optical connector90is inserted into the hole85of the cap6, and the connection surface91ais pushed against the thread support surface S of the cleaning pin44. In the same manner as when cleaning the female optical connector3, the slider10is moved forward against the slider return spring13, thereby integrally rotating the rotary pod40and cleaning pin44. This makes it possible to clean the connection surface91aby the cleaning thread41.

The second embodiment of the present invention will be explained below with reference toFIGS. 7 to 24.

An optical connector cleaning tool100according to this embodiment is applied to cleaning of an SC or FC type optical connector3(e.g., a connector defined by JIS C 5973 or 5970) in which the outer diameter of a ferrule4is 2.5 mm. Big differences from the optical connector cleaning tool1disclosed in the first embodiment described above are that the maximum rotational angle of a rotary pod40is 180°, and that a cleaner5has a guide portion101and thread slack preventing mechanism102. Accordingly, arrangements different from the above-mentioned first embodiment will mainly be explained, the same reference numerals denote almost the same constituent members and portions, and a repetitive explanation will be omitted.

Referring toFIGS. 7 to 11, the optical connector cleaning tool100includes a holder2, the cleaner5, a cap6, the guide portion101, and the thread slack preventing mechanism102.

Similar to the first embodiment described above, the holder2includes a slider10, a lid11that closes the rear-end opening of the slider10, a body12partially accommodated in the slider10, a slider return spring13, and a shaft14.

Elastic pieces16of the slider10are thin and long plate-like pieces each having two side edges separated from the slider10and two ends supported by it. A guide projection17is integrally formed on the center of the back surface of each elastic piece16.

An annular groove104into which the cap6is to be detachably inserted is formed in the back surface of the lid11.

The body12is integrally formed by a resin material, and spiral grooves25and26and straight grooves27and28with which the guide projections17of the slider10can engage are formed in the outer circumferential surface of the body12. Since the spiral grooves25and26are formed within the angular range of 180° in the outer circumferential surface of the slider10, the cleaner5can maximally be rotated through 180° by one cleaning operation. When the slider10is moved forward by a maximum stroke in one cleaning operation, therefore, a cleaning thread41cleans the whole of a connection surface4aof the ferrule4once.

The straight groove27has a front end that opens in the front end of the body12, a rear end that communicates with a start end25aof the spiral groove25, and a middle portion that communicates with the terminal end of the spiral groove26. Likewise, the straight groove28has a front end that opens in the front end of the body12, a rear end that communicates with a start end26aof the spiral groove26, and a middle portion that communicates with the terminal end of the spiral groove25. The straight grooves27and28have first halves formed to be slightly shallower than the spiral grooves25and26, and second halves formed to be deeper than the spiral grooves25and26. A slope105(FIG. 11) that gradually lowers forward is formed in the terminal end portion of each of the straight grooves27and28. When the slider10moves forward, the guide projections17move by a maximum distance from the start ends25aand26ato terminal ends25band26bof the spiral grooves25and26, move backward along the straight grooves27and28, and return to the start ends25aand26aof the spiral grooves25and26by climbing over the slopes105.

The cleaner5includes, e.g., the rotary pod40, the cleaning thread41, a supply reel42, a take-up reel43, a cleaning pin44, and a pin biasing spring124that biases the cleaning pin44forward. The supply reel42and take-up reel43are incorporated into the rotary pod40as they are accommodated in a reel accommodating member110as a constituent member of the thread slack preventing mechanism102(to be described later). Also, the supply reel42and take-up reel43are accommodated in the reel accommodating member110such that their axes are perpendicular to each other.

Referring toFIGS. 16,18, and19, the reel accommodating member110is formed into a cylinder having two open ends, and partitioned into two, front and rear chambers113A and113B by a partition112(FIGS. 8 and 10). In the front chamber113A, the supply reel42is accommodated with its axis being perpendicular to that of the reel accommodating member110. In the rear chamber113B, the take-up reel43is accommodated with its axis being aligned with that of the reel accommodating member110. The end portions of a cylinder42A of the supply reel42are rotatably axially supported by a pair of bearings115formed on the circumferential wall of the reel accommodating member110and each having a semicircular recess115a. In addition, removal preventing pieces116inhibit the forward movement of these end portions of the cylinder42A. The removal preventing pieces116are elastically deformable in the direction of thickness, and positioned before the bearings115. When incorporating the supply reel42into the chamber113A, the removal preventing pieces116elastically deform outward as they are pushed by the end portions of the cylinder42A, thereby engaging the end portions of the cylinder42A with the bearings115. After that, the removal preventing pieces116elastically return to prevent removal from the bearings115.

The take-up reel43is rotatably axially supported by a shaft pin116projecting from the partition112of the reel accommodating member110, and a shaft pin117projecting from a clutch plate150(to be described later).

Referring toFIG. 12, the guide portion101is formed on the outer circumferential surface of the cleaner5. When the optical connector cleaning tool100is not in use, the guide portion101protects, together with the cap6, a thread support portion44B of the cleaning pin44and the cleaning thread41that are exposed outside the rotary pod40. During cleaning, the guide portion101guides the distal end portion of the cleaner5to a receptacle7. The guide portion101includes a guide lock121attached to the rotary pod40, a guide member122that covers the outer circumferential surface of a cylindrical portion40C of the rotary pod40, and a guide biasing spring123that biases the guide member122forward.

The guide lock121is formed into a frustoconical shape, and fitted on the front surface of a pod main body40A of the rotary pod40. The guide lock121is detachably fixed by engagement of a plurality of engaging pieces131and a plurality of locking holes132. The front opening of the guide lock121forms a straight hole126, and the guide member122is slidably inserted into the hole126.

The guide member122is formed into a cylindrical member, and fitted on the cylindrical portion40C of the rotary pod40so as to be movable forward and backward. A flange127is integrally formed at the rear end of the guide member122. The flange127abuts against a step128formed at the rear end of the hole126, thereby preventing the removal of the guide member122from the guide lock121.

The guide biasing spring123is elastically installed in an annular gap between the outer circumferential surface of the rear end portion of the cylindrical portion40C of the rotary pod40and the inner circumferential surface of the rear end portion of the guide member122. Since the front end is urged against a step129formed on the inner surface of the guide member122and the rear end is urged against the front surface of the main body40A of the rotary pod40, the guide biasing spring123biases the guide member122forward to press the flange127of the guide member122against the step128of the guide lock121. In this state, the distal end of the guide member122is positioned before the cleaning pin44, and surrounds the circumferential surface of the thread support portion44B of the cleaning pin44, which projects from the rotary pod40. This prevents dust or the like from sticking to the cleaning thread41supported by a thread support surface S, or prevents an operator from touching and contaminating the cleaning thread41by mistake. This also prevents damage to the thread support portion44B caused by collision against the wall surface or the like. The pin biasing spring124is elastically installed in an annular gap between the outer circumferential surface of the front end portion of the cylindrical portion40C of the rotary pod40and the inner circumferential surface of the front end portion of the guide member122, and biases the cleaning pin44forward. The front end of the pin biasing spring124is urged against a flange140formed on the cleaning pin44, and the rear end of the pin biasing spring124is urged against a step141formed on the cylindrical portion40C of the rotary pod40. The spring force of the guide biasing spring123is set weaker than that of the slider return spring13. Also, the spring force of the pin biasing spring124is set weaker than that of the guide biasing spring123.

Referring toFIGS. 13 to 15, the cleaning pin44integrally includes a columnar main body44A, the thread support portion44B integrally formed at the front end of the main body44A, and the flange140formed in the boundary between the main body44A and thread support portion44B, and two thread insertion grooves65A and65B are formed in the outer circumferential surfaces of the main body44A and thread support portion44B so as to be spaced apart by 180° in the circumferential direction. The thread insertion grooves65A and65B are formed to have a length extending from the vicinity of the front end of the thread support portion44B to the vicinity of the rear end of the main body44A. Also, the rear end portion of the main body44A is split by a slit143to form a pair of elastic deformation portions44F and44G facing each other. A stopper66is integrally formed at the distal end portion of the outer circumferential surface of each of the elastic deformation portions44F and44G. The slit143communicates with the thread insertion grooves65A and65B. When inserting the cleaning pin44into the cylindrical portion40C of the rotary pod40, the elastic deformation portions44F and44G elastically deform inward to make it possible to attach the cleaning pin44to the rotary pod40. The stoppers66engage with a front end edge147aof an opening147formed in the cylindrical portion40C of the rotary pod40, thereby positioning the cleaning pin44and preventing its removal from the rotary pod40.

A distal end face142of the cleaning pin44is formed into a flat surface, a recess141is formed in the central portion, and the bottom surface of the groove forms the flat thread support surface S for supporting the cleaning thread41. A thread extracting hole144and thread introducing hole145communicating with the thread insertion grooves65A and65B are formed on the two sides of the thread support surface S. A tapered surface143is formed between the outer circumferential surface of the recess141and the thread support portion44B. The tapered surface143decreases the outer diameter of the distal end face142. Even when the ferrule4is an oblique contact type ferrule, therefore, the edge of the ferrule end face4adoes not abut against the distal end face142as shown inFIG. 15, so the thread support surface S can approach the ferrule end face4a. The cleaning thread41is guided to the thread insertion groove65A through the rotary pod40, and supplied forward through the thread extracting hole144. After that, the cleaning thread41is inserted into the thread introducing hole145across the thread support surface S, and guided into the rotary pod40through the thread insertion groove65B.

The thread slack preventing mechanism102prevents a slack and rewind of the thread caused by idling of the supply reel42or take-up reel43, and ensures stable and reliable supply and take-up of the cleaning thread41. The thread slack preventing mechanism102includes, e.g., the supply reel42, the take-up reel43, the reel accommodating member110, the clutch plate150, a latch mechanism180, first and second unidirectional clutches190and191, and a clutch biasing spring151.

As described previously, the reel accommodating member110is formed into a cylinder having two open ends by using a resin material. The reel accommodating member110is fitted inside the body12so as not be rotatable, and rotates together with the body12. Also, the reel accommodating member110has the two, front and rear chambers113A and113B for accommodating the supply reel42and take-up reel43, and a pair of transparent windows152for allowing external visual check of the front chamber113A are formed in the circumferential wall so as to be spaced apart by 180° in the circumferential direction. The transparent windows152are rectangular parallelopiped projections and fitted in openings153(FIG. 10) formed in the circumferential wall of the body12, so the surfaces of the transparent windows152are exposed outside the body12. By visually checking the supply reel42accommodated in the chamber113A through the transparent windows152, it is possible to confirm the remaining amount of an unused cleaning thread41.

The circumferential wall of the reel accommodating member110has the pair of bearings115, the pair of removal preventing pieces116, a pair of elastic pieces154, a pair of engaging projections155, and a pair of openings156formed apart by 180° in the circumferential direction, a thread insertion hole167, a thread insertion groove168, and a plurality of slits169. As described previously, the bearings115axially support the end portions of the cylinder42A of the supply reel42, and the removal preventing pieces116prevent the removal of the end portions from the bearings115. The thread insertion groove168guides the used cleaning thread41to the take-up reel43, and has a front end that opens in the front end of the reel accommodating member110, and a rear end that communicates with the thread insertion hole167. The slits169divide the rear end of the reel accommodating member110at predetermined intervals in the circumferential direction, thereby forming, e.g., four circular tongue pieces170that are elastically deformable in the direction of thickness. Of the four tongue pieces170, spring receivers171integrally protrude inward from the distal ends of two tongue pieces170facing each other. The spring receivers171prevent the removal of the clutch plate biasing spring151from the reel accommodating member110by supporting the rear end of the clutch plate biasing spring151.

The clutch plate150is formed into a circular disk having an outer diameter slightly smaller than the inner diameter of the reel accommodating member110, and accommodated together with the take-up reel43and clutch biasing spring151in the rear chamber113B of the reel accommodating member110. When accommodating the clutch plate150in the rear chamber113B, the clutch plate150is inserted with the tongue pieces170of the reel accommodating member110being elastically deformed outward. The shaft pin117for rotatably axially supporting the rear end of the take-up reel43integrally projects from the center of the front surface of the clutch plate150, and a cylinder175having a hexagonal hole174integrally projects from the center of the back surface. The cylinder175is inserted into the slider10through a partition33(FIGS. 8 and 10) formed inside the body12, and slidably fitted on the shaft14. The clutch biasing spring151is accommodated together with the take-up reel43in the rear chamber113B of the reel accommodating member110. The front end is urged against the back surface of the clutch plate150, and the rear end is stopped by the spring receivers171of the reel accommodating member110. Thus, the clutch biasing spring151pushes the clutch plate150against the take-up reel43via the second unidirectional clutch191, and pushes the take-up reel43against the first unidirectional clutch190.

Referring toFIG. 18, the latch mechanism180prevents idling of the supply reel42, and includes a serrated portion182radially formed over the entire outer circumferential surface of each of flanges42B and42C of the supply reel42, and a projection183formed on the elastic piece154. The serrated portion182have projections182aand recesses182bhaving a triangular shape that increases the width from the center to the periphery of the flange42B or42C, and has two sides having the same inclination angle. The elastic piece154integrally projects from the partition112of the reel accommodating member110, and the projection183is integrally formed on a surface facing the supply reel42. The projection183is a triangle having the same size as that of the projections182aand recesses182b, has a narrow distal end, and increases the width toward the rear end. The projection183brakes the supply reel42by engaging with the recess182b.

The latch mechanism180including the serrated portion182and projection183as described above can reliably prevent a slack of the cleaning thread41wound around the supply reel42. That is, when the slider10is moved forward to integrally rotate the body12, reel accommodating member110, supply reel42, and take-up reel43during cleaning, tension is given to the cleaning thread41, so the cleaning thread41wound around the supply reel42is supplied, and the cleaning thread41used in cleaning is taken up to the take-up reel43. The supply reel42rotates by the tension of the cleaning thread41but does not idle because the projection183sequentially climbs over the serrated portion182, thereby holding the tension of the cleaning thread41almost constant, and smoothly feeding it. Accordingly, the cleaning thread41does not slack.

When one cleaning operation is complete by moving the slider10forward by a maximum stroke, the body12and reel accommodating member110stop. Therefore, the projection183keeps engaging with the serrated portion182, and prevents idling of the supply reel42. This makes it possible to hold the tension of the cleaning thread41constant and prevent a slack of the cleaning thread41in this case as well. When one cleaning operation is complete, the guide projections17of the slider10return to the initial positions through the straight grooves27and28as described earlier. In this state, the body12and reel accommodating member110do not rotate, and the projection183keeps engaging with the serrated portion182. Accordingly, the supply reel42holds the tension of the cleaning thread41constant and prevents a slack of the cleaning thread41.

Referring toFIG. 19, the first unidirectional clutch190is turned on to transmit the rotation of the reel accommodating member110to the take-up reel43when the slider10moves forward, and turned off to interrupt the transmission of the rotation to the take-up reel43when the reel accommodating member110rotates in the opposite direction. The first unidirectional clutch190includes a serrated portion194formed on the outer surface of the flange43B on the front side of the take-up reel43, and projections195formed on the partition112of the reel accommodating member110. The serrated portion194has projections194aand recesses194bhaving a right-angled triangular shape that increases the width from the center to the periphery of the flange43B. The projection194ais formed into a sawtooth shape; a surface facing the rotational direction (the clockwise direction inFIG. 19) when the cleaning thread41is taken up is a vertical surface, and a surface opposite to the rotational direction is a slope. The projections195have the same shape as that of the projections194aand recesses194b. For example, three projections195are formed at equal intervals in the circumferential direction of the partition112, and mesh with the serrated portion194. During cleaning, therefore, the first unidirectional clutch190can reliably transmit the rotation of the reel accommodating member110to the take-up reel43, and take up the cleaning thread41. That is, when the body12is rotated by moving the slider10forward during cleaning, the reel accommodating member110rotates together with the body12inFIG. 19. In this state, the serrated portion194and projections195keep engaging with each other. Accordingly, the rotation of the reel accommodating member110is transmitted to the take-up reel43via the first unidirectional clutch190, thereby rotating the take-up reel43in the take-up direction. Consequently, the cleaning thread41is given tension and taken up to the take-up reel43. On the other hand, when the reel accommodating member110reversely rotates, the projections195climb over the serrated portion194. Therefore, the rotation of the reel accommodating member110is not transmitted to the take-up reel43.

The second unidirectional clutch191is turned on to transmit the rotation of the clutch plate150to the take-up reel43when the slider10moves backward, and turned off to interrupt the transmission of the rotation to the take-up reel43when the slider10moves forward. The second unidirectional clutch191includes a sawtooth-shaped serrated portion200formed on the outer surface of the flange43C on the rear side of the take-up reel43, and projections201formed on the front surface of the clutch plate150. The serrated portion200has projections200aand recesses200bhaving a right-angled triangular shape that increases the width from the center to the periphery of the flange43C. The projection200ais formed to have a right-angled triangular sectional shape; a surface facing the rotational direction (the clockwise direction inFIG. 19) when the cleaning thread41is taken up is a slope, and a surface opposite to the rotational direction is a vertical surface. That is, the serrated portion200of the second unidirectional clutch191has the same shape as that of the serrated portion194of the first unidirectional clutch190, but the direction of the shape is reversed. The projections201of the clutch plate150have the same shape as that of the projections200aand recesses200b, and three projections201are formed at equal intervals in the circumferential direction of the clutch plate150.

The second unidirectional clutch191can prevent a slack of the cleaning thread41especially when the slider10is returned to the initial position by interrupting a cleaning operation halfway after it is started. That is, when the cleaning operation is interrupted halfway without moving the slider10forward by a maximum stroke, the guide projections17return to the initial positions through the spiral grooves25and26as described previously. This rotates the body12, reel accommodating member110, take-up reel43, clutch plate150, and the like in the direction opposite to that during cleaning. Since the first unidirectional clutch190is OFF in this state, the take-up reel43may idle and slack the cleaning thread41. In this state, the second unidirectional clutch191is ON and hence transmits rotation to the reel accommodating member110. Accordingly, the take-up reel43does not idle and keeps giving tension to the cleaning thread41, thereby preventing a slack of the cleaning thread41.

The operations of the cleaner5and guide portion101when cleaning the ferrule end face of an SC type optical connector by using the optical connector cleaning tool100having the structure as described above will be explained below with reference toFIGS. 12 and 20to24.

FIGS. 12,20and21illustrate a state before the optical connector cleaning tool100is inserted into the receptacle7. A sleeve holder220, a sleeve221, and a pair of locking pieces224are formed in the receptacle7. The sleeve holder220has an outer diameter slightly smaller than the inner diameter of the distal end portion of the guide member122. The sleeve221positions the ferrule4with respect to the sleeve holder220, and is installed inside the sleeve holder220. The inner diameter of the sleeve221is almost equal to the outer diameter of the ferrule4, and slightly larger than the outer diameter of the thread support portion44B of the cleaning pin44. The pair of locking pieces224clamp the distal end portion of the guide member122, and fix the distal end portion to the receptacle7. The pair of locking pieces224face each other with the sleeve holder220being interposed between them. Reference numeral225denotes the inner wall of the receptacle7;226, an optical fiber; and227, a housing.

In the state (FIGS. 20 and 21) before the optical connector cleaning tool100is inserted into the receptacle7, the guide member122is positioned on the front side by the spring force of the guide biasing spring123, and covers the thread support portion44B of the cleaning pin44. The distal end of the cleaning pin44is behind the distal end of the guide member122by 0.8 mm (2.55 mm when the diameter is 1.25 mm).

FIG. 22shows a state in which the distal end portion of the optical connector cleaning tool100is inserted halfway into the receptacle7. When an operator gradually inserts the distal end portion of the optical connector cleaning tool100into the receptacle7by holding the slider10, the distal end of the guide member122enters the gap between the sleeve holder220and locking pieces224while elastically deforming the locking pieces224outward. When a predetermined amount of the distal end portion of the optical connector cleaning tool100is inserted into the receptacle7, the distal end of the guide member122abuts against the inner wall225of the receptacle7and stops (FIG. 22). When the optical connector cleaning tool100is further pushed into the receptacle7, the guide biasing spring123is gradually compressed, and the rotary pod40moves forward to bring the distal end of the cleaning pin44into contact with the ferrule end face4a.FIG. 23shows this state. In this state, the guide member122is relatively behind the cleaning pin44by 0.8 mm (the initial cleaning pin withdrawal amount from the guide member distal end)+Y mm owing to the contraction of the guide biasing spring123. Note that Y (FIG. 23) is the distance between the inner wall225of the receptacle7and the ferrule end face4aand, e.g., 1.3 mm.

FIG. 24shows a state in which the optical connector cleaning tool100is further pushed into the receptacle7to relatively retreat the guide member122by 5 mm (a maximum amount by which the guide member can retreat from the rotary pod40)−2.1 mm=2.9 mm. Consequently, the cleaning pin44also retreats 2.9 mm from the rotary pod40, and the pin biasing spring124contracts 2.9 mm. When the guide member122retreats the maximum distance, its rear end abuts against the front surface of the main body40A of the rotary pod40and stops, and the guide member122is completely connected to the rotary pod40. In this state, the guide biasing spring123has reached its limit, i.e., cannot be compressed any more because the deformation amount has become maximum and adjacent coils are in tight contact with each other. On the other hand, the pin biasing spring124has not reached its limit yet, and keeps pressing the cleaning pin44against the end face4aof the ferrule4by a predetermined pressing force.

When the guide member122is further pressed against the sidewall225of the receptacle7, the guide biasing spring123is not compressed because it has already reached its limit, and the slider10starts advancing against the slider return spring13. That is, the slider return spring13in a compressed state is incorporated into the slider10in the initial state. Therefore, the slider return spring13does not contract unless the force with which the distal end of the guide member122pushes the inner wall225of the receptacle7exceeds the restoration force of the slider return spring13. Since the pushing force of the distal end of the cleaning pin44has become a predetermined load before this restoration force is reached, the slider return spring13does not start contacting against its restoration force unless the distal end of the cleaning pin44is set in a state suited for cleaning. Accordingly, the slider10starts advancing toward the body12, and the guide projections17advance along the spiral grooves25and26, thereby rotating the body12. Consequently, the rotary pod40, guide member122, and cleaning pin44rotate together with the body12, and the cleaning thread41cleans the ferrule end face4a. Therefore, no part of the ferrule end face4aremains unwiped, so the whole of the ferrule end face4acan reliably be cleaned. That is, if the guide member122, cleaning pin44, and biasing springs13,123, and124do not operate as described above and the cleaning pin44starts rotating before it abuts against the ferrule end face4a, the cleaning thread41cleans the ferrule end face4aat an angle of 180° or less, and pieces an unwiped portion behind. In the above-mentioned structure, however, the body12, rotary pod40, cleaning pin44, and the like can be rotated after the cleaning pin44comes in contact with the ferrule end face4a. Since this eliminates the above-mentioned phenomenon in which an unwiped portion remains, the whole of the ferrule end face4acan reliably be cleaned.

As described above, the optical connector cleaning tool100according to this embodiment achieves the following effects because it includes the guide portion101.

(1) Except when performing cleaning, the guide portion101protects the cleaning pin44by positioning it inside the guide member122. This makes it possible to prevent an accident in which the cleaning pin44hits against something and breaks except when performing cleaning.
(2) The guide biasing spring123biases the guide member122forward. After the distal end of the guide member122is urged against the inner wall225of the receptacle7, therefore, the body12, rotary pod40, and cleaning pin44relatively move forward, so the cleaning pin44can reliably be inserted into the sleeve221.
(3) The outer diameter of the distal end portion of the guide member122is set to an optimum dimension corresponding to the internal shape of the receptacle7. When inserting the guide member122into the receptacle7, therefore, the distal end of the guide member122is naturally guided and inserted into the receptacle7without accurately aiming at the center of the ferrule4. This makes it possible to reliably bring the cleaning pin44into contact with the ferrule end face4awithout operator's awareness.

FIG. 25shows an optical connector cleaning tool250according to the third embodiment of the present invention. The optical connector cleaning tool250is applied to MU and LC type optical connectors (ferrule diameter=1.25 mm). Big structural differences from the optical connector cleaning tool100disclosed in the second embodiment described above are the differences between the SC or FC type optical connector and the MU or LC type optical connector, i.e., the differences in receptacle opening shape, ferrule diameter, and distance Y between the receptacle inner wall and the ferrule distal end. Therefore, the differences are the distal end shape of a cleaner5, the dimension of insertion into a receptacle, the outer diameter of a thread support surface S of a cleaning pin44, the distal end shape of a guide member122, and the like. The rest of the structure is almost the same as that of the above-mentioned optical connector cleaning tool100for the SC and FC type optical connectors. Accordingly, a holder2is used as a common part for all types of connectors, and cleaners5are prepared for the and FC type connectors and the MU and LC type connectors. A cleaner5corresponding to an optical connector3to be cleaned need only be selected and attached to the holder2.

More specifically, the opening shape of a receptacle7and the distance Y between an inner wall225(FIG. 20) of the receptacle7and the ferrule distal end change in accordance with the type of optical connector. This makes the distal end shape and length of the guide member122for the SC and FC optical connectors different from those for the MU and LC optical connectors.

It is necessary to meet various opening shapes of the receptacles7. For a ferrule diameter of 2.5 mm, therefore, the distal end of the guide member122has an outer diameter having a dimension that allows insertion into the receptacles7of both the SC and FC type optical connectors, and an inner diameter larger than the outer diameter of a sleeve holder220, so both the optical connectors can be cleaned. Also, with respect to the opening of the receptacle7of particularly the type optical connector, the distal end of the optical connector cleaning tool250is naturally guided by locking pieces224without accurately aiming at the center, and the guide member122is smoothly inserted into the receptacle7, so the cleaning pin44is inserted into a sleeve221without operator's awareness. Note that the outer diameter of the cleaning pin44is slighter smaller than 2.5 mm as the inner diameter of the sleeve221. More specifically, the cleaning pin44has a distal end portion (length=about 4 mm) having a diameter of 5.9 mm corresponding to the FC type optical connector, and a rear end having a diameter of 6.4 mm that stabilizes insertion into the SC type optical connector. The guide member122has an inner diameter of 4.9 mm corresponding to the SC type optical connector in which the sleeve holder220has a large outer diameter.

This similarly applies to an optical connector cleaning tool for a ferrule diameter of 1.25 mm. That is, the optical connector cleaning tool can clean both the MU and LC type optical connectors and can readily be inserted into the receptacle7, so the cleaning pin44can be inserted into the sleeve221without operator's awareness. Note that the outer diameter of the cleaning pin44is slightly smaller than 1.25 mm as the inner diameter of the sleeve221. More specifically, since the cleaning pin44for the LC type connector has a large flange range depth, a portion about 15 mm long of the distal end portion of the guide member122has an outer diameter of 4.3 mm. Therefore, the optical connector cleaning tool for a diameter of 1.25 mm is longer by about 13 mm (accurately, 13.35 mm) than that for a diameter of 2.5 mm. This makes it possible to make the positions of the flanges140the same in the cleaning pins44for the ferrule having a diameter of 2.5 mm and that having a diameter of 1.25 mm, and make the lengths of the spring accommodating spaces between rotary pods40and the guide members122the same. As a consequence, the same pin biasing spring214can be used.

The values of the distance Y between the receptacle inner wall and ferrule end face are respectively 1.3, 3.7, 1.35, and 0.65 mm for the SC, FC, MU, and LC type connectors. Also, the values of the contraction amount of a guide biasing spring123are respectively 2.9 mm (=5−0.8−1.3), 0.5 mm (=5−0.8−3.7), 1.1 mm (=5−2.55−1.35), and 1.8 mm (=5−2.55−0.65) for the SC, FC, MU, and LC type connectors. Note that the distance Y between the receptacle inner wall and ferrule end face largely changes from one optical connector to another, but no problem arises because the guide return spring123always contracts (at least 0.5 mm) and applies a pressing force.

The above features make it possible to use the identical parts and reduce the cost. That is, it is only necessary to prepare the cleaning pins44and guide members122for the ferrule having a diameter of 2.5 mm and that having a diameter of 1.25 mm in accordance with the types of optical connectors, and selectively use them for the ferrule having a diameter of 2.5 mm and that having a diameter of 1.25 mm while using the identical parts including the guide biasing spring123and pin biasing spring124as the rest of the members.

FIG. 26is a perspective view of the main parts of a cleaning pin according to the fourth embodiment of the present invention.FIG. 27is a sectional view of the main parts of the cleaning pin. In this embodiment, a head44D is integrally formed at the distal end of a thread support portion44B of a cleaning pin44. The head44D has a front surface that forms a flat thread support surface, and is connected to the thread support portion44B with a neck44E being formed between them. The neck44E is elastically deformable and hence can tilt the head44D in all directions. Also, an outer cylinder280made of another member is fitted on the outer circumferential surface of the thread support portion44B, and an annular gap between the outer cylinder280and thread support portion44B forms a thread passage281into which a cleaning thread41is to be inserted.

When using the cleaning pin44as described above, the head44D inclines while ensuring a large contact length between the cleaning thread41and a ferrule4. This makes it possible to reliably clean a ferrule having a ferrule end face that is neither a flat surface nor a spherical surface, e.g., an oblique contact type ferrule as shown inFIG. 15. In addition, it is only necessary to guide the cleaning thread41forward along the outer circumferential surface of the thread support portion44B, extend the cleaning thread41across the front surface of the head44D, and then attach the outer cylinder280to the thread support portion44B. This obviates the need to form the thread extracting hole144and thread introducing hole145shown inFIG. 14in the thread support portion44B, and facilitates attaching the cleaning thread41to the cleaning pin44.

INDUSTRIAL APPLICABILITY

The optical connector cleaning tool according to the present invention can be used for both the female connector3and male connector90.