Patent ID: 8896298

Claim:
A rotation detection device comprising: a rotation detector component configured to detect a rotational state of a rotor and to send a rotational detection signal; a signal transmission component electrically connected with a lead frame of the rotation detector component and configured to transmit the rotational detection signal to an external device; and a body portion holding the rotation detector component and a part of the signal transmission component, wherein the body portion is integrally molded of a first resin, after joining the lead frame of the rotation detector component with the signal transmission component to form a joint portion between the lead frame and the signal transmission component, to cover the joint portion, the rotation detector component, and a part of the signal transmission component, the rotation detector component has a plurality of corners including at least two exposed corners, which are exposed from the body portion, the rotation detector component is encapsulated, excluding the at least two exposed corners, and each of the at least two exposed corners has at least four exposed surfaces.