Abstract: A piston retraction tool is provided. The tool can be operated with one hand. When an operating handle is operated, the helical movements of a first external thread and a second external thread drive a first pressure plate and a second pressure plate to extend and move away from each other. First engaging pieces of first L-shaped elastic plates and second engaging pieces of second L-shaped elastic plates are distributed in the roots and on the crests of the first and second external threads. The helical movements of the first and second external threads don't interfere with each other because the first and second engaging pieces of the first and second L-shaped elastic plates are configured to jump along the first and second external threads independently. The helical movements of the first and second external threads will not be locked.

Abstract: A disc brake piston retraction tool is provided. When the tool is applied to a large-scale disc brake, it is necessary to increase the width in the left-to-right direction of the working surface of a pressure plate of the tool. A plate expansion unit is coupled to the outer surface of the pressure plate. When a locking unit is inserted in a coupling hole of the pressure plate, a steel ball is retracted. After the steel ball passes through the coupling hole, a compression spring rebounds to produce a positioning effect. The backing plate can be easily and quickly mounted to the outer surface of the pressure plate to increase the width of the working surface of the pressure plate. The locking device allows the steel ball to be retracted to exit the coupling hole.

Abstract: A disc brake piston retraction tool includes a reversible ratchet wrench, a first pressure plate assembly, and a second pressure assembly. In the process of retracting a piston, a first engaging notch of a first L-shaped elastic plate of a first buckle member and a second engaging notch of a second L-shaped elastic plate of a second buckle member are pressed against a first force output shaft and a second force output shaft to provide an anti-rotation effect. Thus, when an operating handle of the reversible ratchet wrench is pulled back, it will not link a ratchet wheel, so as to carry out an effective operation of retracting the piston.

Abstract: A disc brake piston retraction tool includes a reversible ratchet wrench, a first pressure plate assembly, and a second pressure assembly. In the process of retracting a piston, a first engaging notch of a first L-shaped elastic plate of a first buckle member and a second engaging notch of a second L-shaped elastic plate of a second buckle member are pressed against a first force output shaft and a second force output shaft to provide an anti-rotation effect. Thus, when an operating handle of the reversible ratchet wrench is pulled back, it will not link a ratchet wheel, so as to carry out an effective operation of retracting the piston.

Abstract: A flat clamping hand tool structure includes a left clamping seat having one side with a left fixing portion facing a right fixing portion on one side of a right clamping seat. The first and second fixing members move up and down in left and right mounting slots of the left and right clamping seats by left and right swing plates which are pivotally connected with upper and lower holders. The left and right clamping seats are guided to move by guiding blocks of the upper and lower holders to slide along guiding grooves of the left and right clamping seats. Left and the right arms pivot together through a first pivot member. Left and right limit portions of the left and right swing plates mesh with each other so as to drive the left and right clamping seats to carry out a clamping motion.

Abstract: A flat clamping hand tool structure includes a left clamping seat having one side with a left fixing portion facing a right fixing portion on one side of a right clamping seat. The first and second fixing members move up and down in left and right mounting slots of the left and right clamping seats by left and right swing plates which are pivotally connected with upper and lower holders. The left and right clamping seats are guided to move by guiding blocks of the upper and lower holders to slide along guiding grooves of the left and right clamping seats. Left and the right arms pivot together through a first pivot member. Left and right limit portions of the left and right swing plates mesh with each other so as to drive the left and right clamping seats to carry out a clamping motion.

Abstract: A carpenter's sawing machine that includes a base, an elongated saw support body, and a saw. The saw support body is pivotally attached to the base to change a first cutting angle of the saw. The saw is pivotally mounted in the saw support base to change a second cutting angle of the saw. The sawing machine is therefore capable of serving as a compound miter saw.