Abstract: A staple gun with a safety device and its safety device are disclosed. The staple gun with a safety device comprises a safety device and a staple-floating unit that are installed in a housing of the staple gun. The safety device includes a safety push sheet and a switch. In a middle portion of the safety push sheet is defined an engaging slot along a staple-discharging direction, and the safety push sheet is further provided with a triggering sheet extending from an upper end thereof. The staple-floating unit is movably connected to the safety device and includes a guide sheet, a control knob, and a positioning pin. The positioning pin can be used to drive the safety push sheet and the guide sheet to move downwards to make the safety push sheet and the guide sheet to protrude out of the staple exit synchronously for facilitating exerting the staple-floating function.

Abstract: A counterforce-counteracting device for a nailer comprises an active device, a rotating member, and a weight device. The active device drives the rotating member and the weight device to move. After the active device moves, the weight device is driven by the rotating member to produce a counterforce, so as to counteract the counterforce of the nailer. Thereby, such a device is secure and is easy to assemble.

Abstract: The present invention relates to a safety switch for an electric nailer including a trigger which can return to original state after being pressed. The safety switch comprises a stop portion and a safety member, the stop portion is formed in the electric nailer. The safety member includes a push plate and an abutting portion, and the safety member is fixed in the electric nailer and can return to its original position after being pressed, the push plate serves to cover the trigger, and the abutting portion abuts against the stop portion. Thus, the electric nailer will be in a safe mode automatically when not in use, and an accident of pressing the trigger by mistake can be prevented.