Abstract: A T-type socket wrench having three hexagonal rods on three ends of a Y-shaped handle, and three double-head hexagon sockets of successive hexagonal holes mounted on the three hexagonal rods and stopped at respective first positions by respective first steel balls for turning hexagon head screws. Each double-head heaxgon socket is moved inwards on the respective hexagonal rod and stopped at a respective second position by a respective second steel ball permitting a hexagon bit of different size on the respective hexgonal rod to project out of the respective double-head hexagon socket for turning a socket head screw or the like.

Abstract: For dismantling a rivet from either side-plate of a link of a bushed chain, a bicycle chain rivet dismantling apparatus comprised of a base having a first bolt hole and a second bolt hole longitudinally aligned at two opposite ends thereof and spaced from an intermediate stop wall, a screw thread bush fastened in said second bolt hole for supporting the link of the rivet to be dismantled, a female screw fastened in said first bolt hole, a pressure screw driven by a telescopic lever to screw in said female screw causing said rivet to be disconnected from either side-plate of said link, and characterized in that said in said bottom platform has a notch on a front face thereof, and said screw thread bush has a side opening longitudinally disposed in line with said side notch for passing therethrough of said rivet and said link after said rivet having been dismantled from either side-plate of said link.

Abstract: In a hand tool for mounting and dismounting bicycle cranks of the type comprising a handle having a hexagonal hole alternatively mounted on a hexagonal collar at the middle of a bolt, which has a hexagon socket at one end and an outer thread portion at an opposite end, or a hexagonal neck at one end of a nut, which has an outer thread portion and is movably mounted on said bolt, to drive said bolt or nut to rotate, wherein said handle has a hexagonal stub tenon, a wedgelike projecting strip and one pair of stub rods respectively made at one end driving a variety of crank fastening caps having different shape of driving tool mounting hole; said bolt has a front rod in relatively smaller outer diameter movably attached with a circular block to protect the front end of the outer thread portion of said bolt. The handle is extendible so that the arm of force can be increased for labor-saving operation.

Abstract: This invention is related to a hand tool specifically designed for operation to mount or remove a bicycle crank to or from the bolted bottom bracket bearing axle of a bicycle frame, which includes a tool handle having a front wedge to serve as a driver, a screw bolt having one end fixedly connected with a socket and having the other end movably connected with a bolted sleeve by means of screw joint. Through the arrangement of the said component parts, the hand tool is very practical for dismounting the fastening elements of bicycle cranks.

Abstract: A self-detachable bicycle auxiliary wheel bracket which can be connected to the free-wheel axle of a bicycle without removing the nut which locks up the free-wheel axle, and comprising an integral recess at the inner top side for receiving therein the nut which locks the free-wheel axle, which recess has a through-hole in the center for insertion therethrough of the bicycle free-wheel axle, and a pair of projecting rods disposed at lateral sides of the recess for inserting into the front notch of the rear fork of the bicycle to stabilize the connection of the bicycle auxiliary wheel bracket to the free-wheel axle.

Abstract: A concealed and built-up type multipurpose hand tool structure which includes a hollow and T-shaped handle for storing a variety of sockets, having middle through-holes to receive therein a variety of hexagonal wrenches or driver heads or other cylindrical tool parts.