Abstract: For a balance adjustment due to a reduction in size and weight of an actuator, an arm portion, an axis attaching portion, and a coil supporting portion are arranged so that the centers of gravity on the coil side are located on a straight line connecting a rotational center and the center of gravity on the head side. Further, the improvement of an assembling efficiency of a VCM, an increase in torque, a one-touch fixing of an FPC connecting band, a noise prevention of a read pattern, and an insulation between the base and cover due to a bias of an MR read head are accomplished. A sector mark is detected by comparing a peak detection pulse and its reference polarity signal. A redundancy is provided to a reference detection polarity signal so that a read signal can be detected even if any one of the read signals of the sector marks is dropped out.

Abstract: A syringe assembly includes a syringe body, and a plunger having a main body and a gasket mounted on its distal end portion. A needle-mounting member is detachably mounted on a distal end portion of the plunger main body. A plunger-engaging mechanism is provided on the needle-mounting member. An engaging member is provided on a distal end of the gasket, for engaging with the plunger-engaging mechanism. The needle-mounting member and the plunger further have a first structure which transmits a torque from the plunger in a direction to release an engagement between the syringe main body and the needle-mounting member to the needle-mounting member, and a second structure which releases an engagement between the engaging member and the plunger-engaging mechanism through a rotation of the plunger in a direction to keep an engagement between the needle-mounting member and the plunger main body.