A nunchaku includes a joint pin for connecting a baton of the nunchaku to a chain. The joint pin includes a front section for extending through a bearing mounted inside the baton to project from an inner end of the baton to connect to the chain, and a circular flange provided at a rear end of the joint pin to abut against an inner side of the bearing. The flange of the joint pin has an outer diameter larger than an inner bore of the bearing and therefore effectively prevents the whole joint pin and accordingly the chain from separating from the baton even when the steel balls of the bearing are badly worn off and fail to engage with the joint pin.

FIELD OF THE INVENTION

The present invention relates to a nunchaku, and more particularly to a nunchaku having a joint pin that ensures secure connection of a baton of the nunchaku to a chain without the risk of unexpected separation of the baton from the chain.

BACKGROUND OF THE INVENTION

FIGS. 1,2, and3illustrates a joint pin3for connecting a baton5of a nunchaku to a chain1via a bearing2mounted in an end of the baton5. The joint pin3is provided at a predetermined position with an annular groove31about 10 mm in depth. The joint pin3has an outer diameter close to an inner bore21of the bearing2, and could therefore be extended through the bore21of the bearing2to project from the end of the baton5to rotatably connect to an end of the chain1. Steel balls22mounted in the inner bore21of the bearing2are engaged with the annular groove31on the joint pin3, allowing the baton5to smoothly rotate relative to the joint pin3and the chain1when the baton5is thrown or otherwise manipulated. The above-structured nunchaku necessitates the steel balls22of the bearing2to have a high friction coefficient and considerably high frequency of use to therefore subject to wear, that constantly reduces an outer diameter of the steel balls22to cause gaps between the steel balls22and the annular groove31of the joint pin3. The gaps gradually increase with the use of the nunchaku and the steel balls22would eventually fail to effectively engage with the joint pin3via the annular groove31. Under this condition, it is very possible for the joint pin3to disengage from the bearing2, resulting in unexpected and dangerous separation of the baton5from the chain1while it is thrown outward. It is therefore desirable to improve the conventional nunchaku to eliminate such problems.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide a nunchaku that is safer and more reliable for use without adversely affecting its simple structure, designed function, and easy assembling.

To achieve the above and other objects, the nunchaku of the present invention includes an improved joint pin for connecting a baton of the nunchaku to a chain.

The joint pin includes a front section for extending through a bearing mounted inside the baton to project from an inner end of the baton to connect to the chain, and a circular flange provided at a rear end of the joint pin to abut against an inner side of the bearing. The flange of the joint pin has an outer diameter larger than an inner bore of the bearing and therefore effectively prevents the whole joint pin and accordingly the chain from separating from the baton even when the steel balls of the bearing are badly worn off and fail to engage with the joint pin.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer toFIG. 9that shows a nunchaku according to the present invention. As shown, the nunchaku includes two batons5connected end to end via a chain1. Each of the two batons5is connected at an inner end to an end of the chain1via a bearing2mounted inside the inner end of the baton5and a joint pin4rotatably connected to the bearing2and projected from the inner end of the baton5.

Please refer toFIGS. 4,5, and6at the same time. The joint pin4includes a front section41, an annular groove42provided near a rear part of the front section41, and a circular flange43provided at a rear end of the joint pin4close to the annular groove42. The bearing2has an inner bore21close to an outer diameter of the front section41of the joint pin4, so that the front section41of the joint pin4could be extended through the inner bore21of the bearing2to project from the inner end of the baton5with the flange43abutted on an inner side of the bearing2and the annular groove42engaged with a plurality of steel balls22rotatably seated in the inner bore21of the bearing2. The front section41of the joint pin4projected from the inner end of the baton5is then rotatably connected to an end of the chain1, as shown in FIGS.7and8.

The flange43has a thickness about 0.1 cm, and an outer diameter about 0.5 cm larger than the inner bore21of the bearing2. Therefore, the flange43abutted on the inner side of the bearing2could absolutely safely prevent the whole joint pin4from moving out of the bearing2to dangerously separate from the baton5.

When the chain or anyone of the batons5of the nunchaku of the present invention is thrown or otherwise manipulated in any manner to pull the joint pin4, the flange43of the joint pin4connecting the baton5to the chain1is always abutted against the inner side of the bearing2, even if the steel balls22of the bearing2have been badly worn off to lose their function of engaging with the annular groove42of the joint pin4.