Abstract: The driver bit according to the present invention includes: a tip on which a cross blade is formed; a torque transmitting part having a polygonal outer circumference; and a locking groove which extends in the circumferential direction between the tip and the torque transmitting part and into which locking balls enter, wherein the tip has four blade forming grooves forming the cross blade, the blade forming grooves are continuous with the locking groove, and the blade forming grooves are arranged so that the blade forming grooves have bottom parts, at which they are connected with the locking groove, located inwardly of the outer circumference of the torque transmitting part, and the center lines are displaced from a line connecting the shaft center with vertex positions of the polygonal outer circumference and a line connecting the shaft center with center positions of sides of the polygonal outer circumference.

Abstract: The driver bit according to the present invention includes: a tip on which a cross blade is formed; a torque transmitting part having a polygonal outer circumference; and a locking groove which extends in the circumferential direction between the tip and the torque transmitting part and into which locking balls enter, wherein the tip has four blade forming grooves forming the cross blade, the blade forming grooves are continuous with the locking groove, and the blade forming grooves are arranged so that the blade forming grooves have bottom parts, at which they are connected with the locking groove, located inwardly of the outer circumference of the torque transmitting part, and the center lines are displaced from a line connecting the shaft center with vertex positions of the polygonal outer circumference and a line connecting the shaft center with center positions of sides of the polygonal outer circumference.

Abstract: Disclosed herein is a high-temperature Pb-free solder alloy having the strength required to join electronic parts to a substrate and having excellence in wettability and workability. The high-temperature Pb-free solder alloy contains 0.4% by mass or more but 13.5% by mass or less of Zn, 0.05% by mass or more but 2.0% by mass or less of Cu, 0.500% by mass or less of P, and a balance being Bi except for inevitable impurities. The Pb-free solder alloy may further contain 0.03% by mass or more but 0.7% by mass or less of Al.

Abstract: The socket holder comprises a cylindrical socket section, and a hexagonal prism-shaped shank section which is held in the socket section for transmission of torque to the socket section, and receives torque from a rotating tool. The shank section is detachably fitted to the socket section via a retention mechanism composed of a coil spring and a steel ball. The front end of the shank section is fitted with a thin, cylindrical magnet.

Abstract: Disclosed herein is a high-temperature Pb-free solder alloy having the strength required to join electronic parts to a substrate and having excellence in wettability and workability. The high-temperature Pb-free solder alloy contains 0.4% by mass or more but 13.5% by mass or less of Zn, 0.05% by mass or more but 2.0% by mass or less of Cu, 0.500% by mass or less of P, and a balance being Bi except for inevitable impurities. The Pb-free solder alloy may further contain 0.03% by mass or more but 0.7% by mass or less of Al.