Abstract: The present invention relates to a rotation angle detection device mainly used for rotation angle detection of a steering wheel of an automobile and the like. In the rotation angle detection device of the present invention, support portions for supporting lower surfaces of magnets and retention portions for retaining upper surfaces of the magnets are provided in respective accommodation portions of first and second detection bodies. The magnets are turned in the accommodation portions, and the magnets are press-fitted into lower surfaces of the retention portions so as to be retained and fixed between the support portions and the retention portions. Thereby, an inexpensive rotation angle detection device in which the magnets can be easily and reliably installed in the detection bodies with a simple configuration without individually using holders can be realized.

Abstract: Embodiments of the present invention provide an apparatus, a system, and a method of manufacturer for a magnetic, self-retracting, auto-aligning electrical connector. The apparatus includes a first conductor and a first magnet configured to magnetically couple with a second magnet, wherein magnetic coupling causes a change in a magnetic field of a magnetically coupled combination of the first magnet and the second magnet and wherein the change in the magnetic field causes electrical coupling of the first conductor and a second conductor. The system includes a first connector comprising a first magnet and a first conductor and a second connector comprising a second magnet and a second conductor, wherein magnetic coupling causes a change in a magnetic field of a magnetically coupled combination of the first magnet and the second magnet and wherein the change in the magnetic field causes electrical coupling of the first conductor and the second conductor.

Abstract: A sensor retainer for a bicycle sprocket assembly includes an annular member for mounting and rotating coaxially with the bicycle sprocket assembly and a sensor element fixed to the annular member. Alternatively, the sensor retainer may include a fixing member for mounting a derailleur or other transmission to a bicycle frame and a sensor element mounted to the fixing member.