JPH0495902A - Cord reel for optical fiber - Google Patents

Abstract

PURPOSE:To prevent the optical fiber from being improperly twisted even during the rotation of a rotary drum by connecting the winding start end of the optical fiber which is led out of the rotary drum to a connector installed at the axial center position of the rotary drum. CONSTITUTION:A couple of rotary optical fiber connectors 4 are installed separately on a right and a left side while penetrating bearing cases 7 and 8, and the starting end of the optical fiber cord 2 which is led out of the rotary drum 1 and an optical fiber 11 on an external wiring side are connected to the connectors 4 from inside and outside. Therefore, the optical fiber 11 is never twisted improperly even in a process of extending the optical fiber cord 2 to an optional position at the time of use in a field, i.e. during the rotation of the rotary drum 1. Consequently, a light signal can be transmitted continuously between optical equipments through the optical fiber 11 without any trouble.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is used as a device for freely winding an optical fiber cord connected to an optical control device such as an optical switch and rewinding it once, and is useful for on-site testing of various control systems. This invention relates to a portable optical fiber cord reel used during work.

[Conventional technology]

2. Description of the Related Art As a cord reel for electric wires used for work such as field tests, there is a well-known cord reel in which an electric wire cord is fed out onto a rotating drum of the cord reel and can be freely reeled back once.

[Problem to be solved by the invention]

By the way, when the above-mentioned cord reel for electric wire is used at a site where oil, flammable gas, etc. are handled, the terminal electrical equipment connected to the electric wire fed out from the cord reel and the cord reel itself must also have an explosion-proof structure. Become. For this reason, the structure of the cord reel itself is large and heavy,
Furthermore, there are problems in terms of safety, such as the need for sufficient care when handling them.

On the other hand, recently, in the field of control equipment, optical equipment that applies optical technology has been developed and popularized as an alternative to conventional electrical equipment, and optical fibers are used to transmit optical signals between optical equipment. I try to do that. Optical control systems that use such optical devices in combination with one optical fiber are noise and explosion-proof.

Because it has excellent insulation resistance, it has the advantage that it can be used even in explosion-proof areas without taking special explosion-proof measures. In particular, when an optical fiber is wound on a cord reel instead of an electric wire and used for feeding and rewinding operations, sufficient protection measures are required for the winding mechanism and handling.

The present invention has been made in consideration of the above points, and an object of the present invention is to provide an optical fiber cord reel that can safely handle optical fiber cords, as an alternative to the conventional electric wire cord reel.

[Means to solve the problem]

In order to solve the above problems, the optical fiber cord reel of the present invention is constructed as follows.

(1) A reel body consisting of a rotating drum wrapped with an optical fiber cord and a base supporting the rotating drum is equipped with a rotary optical fiber connector coaxially with the center of the axis of the rotating drum, and the connector Connect the winding start end of the optical fiber cord wound around the rotating drum to.

(2) In addition to the configuration in item (1) above, an automatic optical fiber cord winding mechanism using a constant tension spring mechanism is provided between the rotating drum and the base.

(3) In addition to the configuration in (1) above, there is an automatic optical fiber cord winding mechanism between the rotating drum and the base, and an automatic lock that self-locks the rotating drum at any position where the optical fiber cord is fed out. A mechanism will be established.

[Function] In the configuration described in item (1) above, the rotary optical fiber connector is configured to transmit optical signals between optical fibers via a rotating body, and is already commercially available as a product. By installing such a rotary optical fiber connector at the center of the axis of the rotating drum of the cord reel and connecting the winding start end of the optical fiber pulled out from the rotating drum to the connector, it is possible to perform the unwinding and unwinding operations of the optical fiber cord. Even during the accompanying rotation of the rotating drum, the optical fiber is not unduly twisted, and optical signals can be continuously transmitted between the optical fiber of the external wiring connected to the connector and pulled out.

In addition, the constant tension spring mechanism used in the automatic winding mechanism in the configuration described in item (2) is one in which a long copper strip with a spiral shape is wound around a special take-up reel. When you pull out the end of the reel, the reel rotates and the todai is fed out. At this time, a force acts on the belt itself that tries to wind it back onto the take-up reel and restore it to its original shape, and this force is always constant regardless of the length (stroke) of the belt. Then, the constant tension spring mechanism is pulled out from the take-up reel attached to the base side of the cord reel, and its tip is reversed and wound around another drum attached to the rotating drum side. The tension applied to the unwound optical fiber cord is always constant regardless of the unwinding 1 and the unwinding length of the cord, which allows the unwinding 2 unwinding operation to be performed while safely protecting the optical fiber with low mechanical strength. .

Furthermore, in the configuration of item (3), the automatic locking mechanism for the rotating drum has a rotating stopper formed by an eccentric cam facing the circumferential surface of a disc that rotates together with the rotating drum of the cord reel, and The cam surface is pressed against the disc by a spring, and an operating handle for releasing the lock is attached to the support shaft of the stopper. With this configuration, when the unwinding force of the automatic winding mechanism is applied to the rotating drum, a mimetic action acts between the rotating stopper and the disc, causing the rotating drum to self-lock in that position. Further, in this state, when the handle is operated to separate the cam surface of the rotation stopper from the mating disk, the locked state of the rotation drum is released. Thereby, the rotating drum can be automatically locked at any position where the optical fiber cord is fed out. Note that this locking mechanism does not directly hold down the optical fiber cord itself, so there is no risk of damage due to excessive load being applied to the optical fiber itself.

[Example〕 Embodiments of the present invention will be described below based on the drawings.

First, FIG. 1 shows the structure of the entire cord reel.

In the figure, 1 is an optical fiber cord 2 (two-core cord)
3 is a base that combines two left and right side walls and pivotally supports the rotating drum 1 between them; 4 is a rotary optical fiber connector installed coaxially with the axial center of the rotating drum 1; 5 is an automatic winding mechanism, and 6 is an automatic locking mechanism that self-locks the rotary drum 1 to an arbitrary feeding position of the optical fiber cord 2, and these constitute an optical fiber cord reel as main components.

To describe the structure of each of the above parts in more detail, first,
Cylindrical bearing cases 7.8 are coaxially connected to both the left and right sides of the rotation center of the rotating drum 1, and are connected to the cylindrical main shaft 9 attached to the left and right side walls of the base 3 via ball bearings 10. It is pivoted.

A pair of rotary optical fiber connectors 4 are installed on the left and right sides passing through the bearing case 7.8, and the winding start end of the optical fiber cord 2 pulled out from the rotating drum 1 is connected to the connectors 4.

And an optical fiber 11 on the external wiring side is connected from inside and outside. The general structure of this rotary optical fiber connector 4 is as shown in FIG. 3, in which a pair of left and right sockets 4a and 4b arranged on the same axis are relatively rotatably coupled via a bearing 4c, and each socket The end faces of the optical fiber cords 2 inserted into the cables 4a and 4b are held facing each other in a non-contact manner. Note that 4c is a mounting seat for the connector.

Note that such a rotary type optical fiber connector is commercially available, for example, under the trade name "Optical Rotary Connector RTC Series" (manufactured by Dai-Denshi Kogyo Co., Ltd.).

On the other hand, the automatic winding mechanism 5 described above consists of a spring winding rule 12 pivotally supported on the base 3 and a peripheral surface (shaped in a drum shape) of the left bearing case 7 connected to the rotating drum 1. As shown in FIG. 4, a constant tension spring mechanism is incorporated in which a band-shaped spring 13 is stretched across the gap. Here, spring 1
3 is made of a long belt whose original shape is a spiral, and is wound around a winding loop 12, and the spring 13 pulled out from this is reversed and forms an S-shape on the circumferential surface of the bearing case 7. is wrapped around. With this configuration, when the bearing case 7 is turned together with the rotary drum 1 in the feeding direction by an external force, the spring 13 is drawn out from the take-up reel 12. In this case, the spring that has been reversed from the take-up reel 12 and wound around the bearing case 7 is subjected to a force that tries to wind it back to the take-up reel 12. Therefore, when the external force applied to the rotating drum 1 is removed, the spring 1
3 causes the bearing case 7 and therefore the rotary drum 1 to reverse in the unwinding direction. Moreover, in this case, the force acting on the spring itself is always constant regardless of the length (stroke) of the spring 13 being pulled out.

Further, the automatic locking mechanism 6 described above is configured as follows. That is, a rib-shaped disk 8 is provided on the circumference of the bearing case 8 connected to the right side of the rotating drum 1 shown in FIG.
a is formed. As shown in FIG. 5, an eccentric cam-shaped rotation stopper 6, which functions as a brake shoe, is disposed on the base 3 side facing the disk 8a.
a is installed, and the rotation stopper 6a is urged onto the circumferential surface of the disc 8a by the spring force of a tension spring 6b stretched between the rotation stopper 6a and the fixed part. Further, an operating handle 6d for releasing the lock is attached to the support shaft 6c of the rotation stopper 6a. Note that 6e is a bottle stopper that limits the rotation range of the rotation stopper 6a.

With this configuration, when the bearing case 8 together with the rotary drum 1 receives a rotational force in the rewinding direction by the automatic winding mechanism 5 described above, the rotation stopper 6a in contact with the circumferential surface of the disk 8a rotates around the support shaft 6C. will start rotating clockwise.

By the way, when the rotation stopper 6a, which is an eccentric cam, rotates clockwise, the cam radius up to the point of contact with the disc 8a expands, so a stroke action acts between the rotation stopper 6a and the disc 8a, and the bearing Case 8. Therefore, rotating drum 1
will self-lock into position. On the other hand, when the handle 6d is manually turned counterclockwise in this state, the rotation stopper 6a rotates to the position shown in chain lines in FIG. 5, and is separated from the disc 8a. As a result, the locked state is released and the rotating drum 1 becomes a free state, and is rotated in the rewinding direction by the driving force of the automatic winding mechanism 5 described above.

Note that when the bearing case 8 rotates together with the rotating drum 1 in the feeding direction, the rotation stopper 6a that comes into contact with the circumferential surface of the disk 8a rotates clockwise, so that the rotating drum 1 is rotated by the locking mechanism 6. Not subject to any restrictions.

In FIG. 1, reference numeral 14 indicates a cord presser fixing the starting end of the optical fiber 20 to the rotating drum 1, and reference numeral 15 indicates an optical fiber feed-out guide which is placed between the left and right side walls of the base 3.

Next, an example of actual use of the above-mentioned cord reel and the feeding and rewinding operations of the optical fiber needle will be explained. Figure 2 shows an example of wiring at a work site.
For example, an optical pushbutton switch 16 is connected to the tip of the optical fiber cord 2 fed out from the cord reel, and the optical fiber 11 on the external wiring side pulled out from the rotary optical fiber connector 4 of the cord reel is connected to a manual transceiver 17 (optical pushbutton It is connected to a device that converts the open/closed state of the switch 14 into an electrical signal.

Here, an optical fiber cord 2 is usually wound around a rotating drum 1 of a cord reel. When the user holds the tip of the optical fiber cord 2 and pulls it, the rotating drum 1 rotates and the cord is fed out. Further, when the optical fiber cord 2 is loosened after being pulled out to the working position, the automatic locking mechanism 6 described above operates and the rotating drum 1 is self-locked to the cord pulling out position. On the other hand, when rewinding the optical fiber cord 2 onto the cord reel after the work is completed, by operating the handle 6d of the automatic locking mechanism 6 to release the lock, the rotary drum 1 is rotated by the action of the automatic winding mechanism 5. The rewinding direction is reversed, and as a result, the cord is wound around the rotating drum with a constant tension, returning to the state at the beginning of use.

(Effects of the Invention) Since the optical fiber cord reel according to the present invention is configured as described above, it has the following effects.

In the structure of claim 1, a rotary optical fiber connector is installed coaxially with the axial center of the rotating drum on a reel body consisting of a rotating drum around which an optical fiber cord is wound and a base that pivotally supports the rotating drum. By connecting the winding start end of the optical fiber cord wound around the rotating drum to the connector, the optical fiber cord can be unwound to any desired position during on-site use, that is, even while the rotating drum is rotating, the optical fiber cord can be without applying excessive twist to the fiber.
Furthermore, optical signals can be continuously transmitted between optical devices through optical fibers without any problems.

Furthermore, unlike conventional cord reels for electric wires, the optical fiber cord reel can be used safely even at sites with a high risk of ignition without taking special explosion-proof measures.

In addition, in the structure of claim 2, an automatic winding mechanism for the optical fiber cord using a constant tension spring mechanism is provided between the rotating drum and the base, so that the optical fiber cord can be fed out and rewinded once. The tension applied to the cord during this process is kept constant regardless of the length of the cord, making it possible to safely protect optical fibers with low mechanical strength.

Furthermore, in the structure of claim 3, an automatic winding mechanism for the optical fiber cord and an automatic locking mechanism for self-locking the rotating drum at an arbitrary feeding position of the optical fiber cord are provided between the rotating drum and the base. As a result, the optical fiber cord can be pulled out to any desired pulling position for work, and after work is completed, the optical fiber cord can be automatically rewound onto the cord reel by releasing the locking mechanism, making operation convenient. . Furthermore, in this case, the automatic locking mechanism locks the rotating drum without holding down the optical fiber cord itself, so there is no risk of damaging the optical fiber.

[Brief explanation of the drawing]

1 to 5 show embodiments of the present invention,
Figure 1 is a sectional view of the entire cord reel structure, Figure 2 is an external view of the cord reel in use, and Figures 3, 4, and 5 are each of the
In Figure 0, which is a schematic structural sectional view of a rotary optical fiber connector, a principle diagram of an automatic winding mechanism, and a structural diagram of a locking mechanism, 1: rotating drum, 2: optical fiber cord, 3: base, 4 :Rotary optical fiber connector, 5
: Automatic winding mechanism, 6: Automatic locking mechanism, 10: Ball bearing, 13: Band spring. Representative Patent Attorney Iwao Yamaguchi - 'nee °λ Figure 3 Figure 4

Claims (1)

[Scope of Claims] 1) A portable optical fiber cord reel for reeling out and rewinding an optical fiber cord, which comprises a rotating drum around which the optical fiber cord is wound and a base that pivotally supports the rotating drum. The reel body consisting of a stand is equipped with a rotary optical fiber connector coaxially with the center of the axis of the rotating drum, and the winding start end of the optical fiber cord wound around the rotating drum is connected to the connector. Cord reel for optical fiber. 2) The cord reel for optical fiber according to claim 1, characterized in that an automatic winding mechanism for the optical fiber cord using a constant tension spring mechanism is provided between the rotating drum and the base. . 3) In the cord reel according to claim 1, an automatic optical fiber cord winding mechanism is provided between the rotating drum and the base;
and an optical fiber cord reel, characterized in that it is provided with an automatic locking mechanism that self-locks the rotating drum at an arbitrary feeding position of the optical fiber cord.