Abstract: A bushing structure cooperating with a shaft is disclosed. The bushing structure includes a cylindrical body and an extension portion. The cylindrical body has a shaft hole and the shaft is disposed in the shaft hole. The extension portion is disposed at one end of the cylindrical body and surrounds the cylindrical body. The cylindrical body and the extension portion are made of an iron-contained material.

Abstract: A cutting structure for a utility knife contains: a casing, a holder, a push knob, a positioning member, and two switch buttons. The casing includes two connecting parts, each having a rail, an opening, and a cutout. The holder includes two accommodation grooves, each being arranged on each of two side surfaces of the holder. The push knob is adapted to drive the holder. The positioning member includes a rotary stem and a protrusion. The two switch buttons are mounted in two cutouts of the two connecting parts, and each switch button has a pressing tab extending out of each cutout from an outer wall thereof and its inner wall abuts against each of two side surfaces of the positioning member. Each switch button also has a fixing rib arranged on an inner surface thereof to retain with one of two blades which does not engage with the protrusion.

Abstract: A bushing structure cooperating with a shaft is disclosed. The bushing structure includes a cylindrical body and an extension portion. The cylindrical body has a shaft hole and the shaft is disposed in the shaft hole. The extension portion is disposed at one end of the cylindrical body and surrounds the cylindrical body. The cylindrical body and the extension portion are made of an iron-contained material.

Abstract: Pliers for C-shaped lock rings include a holding unit and a clamping unit. The holding unit is composed of two handles and a control portion. The clamping unit comprises two identical clamping members and a positioning disk. When the control portion is released to engage with the positioning slot to lock the handle; when the control portion is pushed to disengage with the positioning slot, the handle rotate around the center shaft corresponding to the rotations of the clamping unit, such that the clamping members can be open or closed.

Abstract: Pliers for C-shaped lock rings include a holding unit and a clamping unit. The holding unit is composed of two handles and a control portion. The clamping unit comprises two identical clamping members and a positioning disk. When the control portion is released to engage with the positioning slot to lock the handle; when the control portion is pushed to disengage with the positioning slot, the handle rotate around the center shaft corresponding to the rotations of the clamping unit, such that the clamping members can be open or closed.

Abstract: A fan assembly structure is provided. The fan assembly structure comprises a fan, an air-flow guiding structure and a fixing component. The air-flow guiding structure has a plurality of air-flow guiding holes, a leaning portion and a plurality of first locking portions distributed on the leaning portion. The fixing component has a plurality of second locking portions. The fan is pivotally connected with the fixing component. The second locking portion is adapted to rotate by an angle with respect to the leaning portion to lock with the corresponding first locking portion. Thereby, the fan is disposed on the air-flow guiding structure by only the fixing component.