Abstract: A ratchet mechanism includes a ratchet gear rotatably received in a tool member. The tool member includes a cusp, and a spring blade engaged on the cusp. A pair of pawls are supported on the spring blade for engaging with the ratchet gear. The spring blade may bias one of the pawls to engage with the ratchet gear and to disengage the other pawl from the ratchet gear. An actuator is rotatably secured in the tool member and includes two actuating surfaces for disengaging the pawls from the ratchet gear and for effectively driving the tool member.

Abstract: A tool includes a base having a stud for engaging with a tool bit and includes a handle having a bore for engaging with the stud of the base. A stem is secured to the handle for engaging with the tool bit. The handle has one or more engaging channels. The base has one or more catches for engaging with the engaging channels and for securing the base to the handle and for increasing the size of the tool. The base has a latch for engaging with the handle and for further securing the base to the handle. A shaft may couple the stud of the base to the stem.

Abstract: A screwdriver has a socket seat, an inner shaft and an outer shaft. The socket seat has an outer wall, a circular crenulation, a central hole, a circular interspace and enlarged blocks. The inner surface of the circular crenulation has three check recesses between two enlarged blocks. The inner shaft has an upper portion in the socket seat and a lower rod. The upper portion of the inner shaft is checked by the inner surface of the socket seat. A positioning portion which is disposed on the upper portion of the inner shaft has spaced flat surfaces and spaced outcurved surfaces formed on the outer periphery alternately. A radial hole is formed on the positioning portion to receive a steel ball which is suppressed by a spring. The steel ball is disposed in any of the check recesses. Each enlarged block is adjacent to a cylindrical check block. A circular cushion is disposed on the check block. An outer shaft has a rod and a circular flange to seal the circular interspace.