OPTICAL CONNECTOR

Abstract: An optical connector having a tubular housing (1) and a cover (2) formed with at least one hole (10) through which an optical fiber cable (8) extends. The cover (2) is formed with a slot (11) extending from its outer periphery to the hole (10). This facilitates connection work.

Description: OPTICAL CONNECTOR The present invention relates to an optical connector in which optical fiber cables are easy to mount and dismount. Optical connectors are used to connect an optical fiber cable or cables with a light emitting element, a light receiving element or another optical fiber cable. Optical connectors are comprised of'male and female connectors which are coupled with each other. An elongated metallic plug is usually attached to the end of-an optical fiber cable. The plug has in the midway of its length a flange portion which is urged forward by a spring. The optical connector comprises a tubular housing for containing the plug and a photoelectric element and a cover for covering the rear end of the housing. In the optical connector for connecting optical fiber cables, the cover is provided with a hole to pass the rear portion of the plug therethrough. The hole is naturally smaller than the diameter of the flange portion of the plug. Therefore, the optical fiber cable must be passed through the cover before the plug is attached to its end. Fig. 7 is an exploded perspective view of the conventional optical connector. The optical connector is composed of a tubular housing 31 and a cover 32. Plugs 33 and springs 34 are contained in the housing. Two optical fiber cables 35 are passed through holes 36 of the cover 32 into the plugs 33 and bonded to their inner wall. The plugs 33 thus secured to the ends of the optical fiber cables are in turn introduced into an opening 37 in the housing 31. On its front surface the cover 32 is formed with extension members 38 n parallel with each other and each having a jaw 39 disposed at its tip and being at a right angle to its axis. The housing 31 is formed with projections 40 on the outer wall thereof. When the jaws 39 are engaged onto the projections 40, the housing 31 is coupled with the cover 32. The spring 34 held between the flange portion 41 and the cover 32 will urge the plug 41 forwardly. If the diameter of the hole is expressed as As the spring's diameter as B and the diameter of flange portion as C, the following relationship is required in order that the spring 34 properly functions between the cover 32 and the flange portion 41. A < B < C (1) If AaB, the spring 34 would slip through the hole 36. The spring and the flange portion can not be passed through the hole. Hence, only after the cable 35 has been passed through the hole 36, the spring 34 is mounted on the cable, and then the jacket covering the end of the cable is peeled off, and the cable is secured to the plug. However, with the cover mounted on the optical fiber cables, it may be obstructive to the working on the ends of the cables. In particular, if the freely movable portion of the cable is short, the cover mounted on the optical fiber cables will decrease the efficiency in the plug fitting operation. Moreover, even if only the cover suffered a damage, only it can not be replaced because the plugs can not be removed from the cover. An object of the present invention is to provide an optical connector which deviates such defects. In accordance with the present invention, the optical connector is formed with slots communicating with the holes in the cover for the passage of plugs. The slots will enable the optical fibers with the plugs already attached to pass through the holes. The arrangement, actions and effects according to the present invention will now be described with reference to the accompanying drawings, in which: Fig. 1 is an exploded perspective view of the optical connector embodying the present invention; Fig. 2 is a vertical sectional view of the same showing the cable with the plug; Fig. 3 is a right side view of a cover used in the second embodiment for connecting a single optical fiber cable; Fig. 4 is a rear view of said cover; Fig. 5 is a vertical sectional view of the second embodiment; Fig. 6 is a left side view of the second embodiment; and Fig. 7 is an exploded perspective view of a conventional optical connector. A housing 1 is a cylindrical body which can hold a pair of plugs therein. A cover 2 serves to cover the rear end of the housing 1. The plugs 3 are so adapted as to protrude forwardly of a partition plate 5 through a hole 4 bored therethrough. Springs 6 mounted on the rear half of the plugs 3 are accommodated in the housing 1, compressed between the cover 2 and flange portions 7 of the plugs Each optical fiber cable 8 is introduced into the plug 3 through an opening at its rear end. The cover 2 is formed with a flange portion 9 and a pair of holes 10 extending axially. The optical connector according to the present invention is characterized in that slots 11 are provided in the cover 2, extending from its periphery to the holes 10. If the width of the slots 11 is called D and the outer diameter of the optical fiber cable 8 is called E, the relationship between D and E can be expressed as follows: ¯¯D > E (2) In the present invention, because the slots 11 are formed in the cover 2, the optical fiber cables 8 do not have to be passed through the holes 10 in the cover 2 any more before the plugs are secured to their ends. Firstly the spring may be fit on the free end of each optical fiber cable 8 and the plug be attached thereto. The optical fiber cable 8 having the spring and plug attached thereto is put into the hole 10 through the slot 11 in the cover 2 at the narrower cable portion (of a diameter E) thereof. Then the cable is pulled back until the plug is passed through the hole 10. The cover 2 is then pushed into the housing 1 so that these two will be combined into one. Means for connecting the cover 2 to the housing 1 may be optionally selected; these two components may be permanently fixed to each other by means of an adhesive, hot calking, supersonic welding, etc. They may also be separably fixed by screws. In the present embodiment, nails adapted to engage projections are used. The housing 1 is provided on the upper and lower inner surfaces with two projections 12, while the cover 2 is formed on its front with two locking pieces 13 which are in the form of fland are spaced vertically. They extend in parallel with each other and have a crossbar 14 at their tip. Furthermore, the housing has a pair of projections 15 extending from its rear surface,. and the cover 2 is provided with holes 16 to receive the projections 15. The cover 2 is pushed into the housing 1, so that the projections 15 will be inserted into the respective holes 16. Further pushing of the cover 2 allows the upper and lower crossbars 14 to slide past the projections 12 and engage thereon. Thus, the housing 1 and the cover 2 are coupled with each other. At the same time, projections 17 disposed on the back of the housing fit into the slots 11 in the cover 2, thereby filling them. The above-mentioned embodiment is a male optical connector designed to connect a pair of optical fiber cables with other cables or elements. The male optical connector is the type of connector that has the plugs and other elements protruding in the housing. In Fig. 2, the plug 3 protrudes outwardly of the partition 5 with the opening 4 therein, so that the plugs can be introduced into a front opening in a female connector (not shown). The male and female connectors are coupled together by an engaging piece 18. However, the present invention may be also applied to a male optical connector for a single optical cable as well as to a female optical connector. In short, the present invention can be applied to any type of optical connector comprising a housing and a cover. The latter two may be coupled together by any means. The present invention is also applicable to an optical connector with no spring in the housing. Figs. 3-6 show an optical connector for a single cable. The cover 2 has a single hole 10 which communicates with the slot 11 as in the first embodiment. In Figs. 5 and 6, the coupling between the cover 2 and the housing 1 is made by the engagement of the projection 12 on the housing with the extension 13 and the jaw 14 on the cover. In this embodiment, no projection is provided to cover the slot 11. As described above in detail, the optical connector according to the present invention is provided with a slot or slots which extends from the periphery of the cover to the bore,.whereby an optical fiber cable in a free state may be attached to the plug. This increases the efficiency in operation and makes possible the replacement of the cover alone. The slots may extend from bottom or sides instead of from top so long as they reach to the bore 10.

Claims: What are claimed are : 1. An optical connector comprising a tubular housing (1) and a cover (2) coupled with said housing for covering one end of said housing, said cover being formed with at least one hole (10) through which an optical fiber cable (8) having a glug attached to one end thereof passes, characte ised in that said cover (2) 1 is formed with at least one slot (11) extending from the outer periphery to the cover to said hole (10). 2. The optical connector as claimed in claim 1 wherein said housing is formed with at least one projection (17) on its surface facing said cover, said projection (17) filling up said slot (11).

Inventors: FUJII, KOJI, HAYASHI, KYOZO, MORIYAMA, MASAKAZU, SAKAMOTO, FUKUMA, SHINOHARA, TOSHIO
Applicants: SUMITOMO ELECTRIC INDUSTRIES LIMITED, TOYOTA JIDOSHA KABUSHIKI KAISHA
Application year: 1982
Main classification: G02B6
IPC codes: G02B6