A saw guard for attachment to a riving knife of a table saw includes a body portion having an elongated shape. The body portions defines a guard portion configured to cover a portion of a saw blade and an attachment portion. The attachment portion extends from the guard portion and defines a slot configured to receive the riving knife. The saw guard further includes an anchor piece connected to the body portion and arranged at least partially in the slot. The saw guard further includes an attachment assembly connected to the body portion and arranged at least partially in the slot and separated from the anchor piece. In a first configuration, the anchor piece and the attachment assembly may define a two-point attachment between the saw guard and the riving knife. In a second configuration, the attachment assembly may permit release of the saw guard from the riving knife.

A machine tool includes a tool and a protective device. The tool includes a saw blade and a motor for driving the saw blade. An insulating member is arranged between the saw blade and the motor. The protective device includes a signal receiving unit, a control unit and a breaker. The signal receiving unit has an antenna receiving end that is in electrical contact with a middle region of the saw blade. The breaker is electrically connected between the motor and a utility power supply. The control unit is connected to the signal receiving unit and the breaker. The saw blade is used as an antenna by the signal receiving unit to receive an electromagnetic wave having the same frequency as that of a utility power from an environment, and the control unit controls the breaker according to a change of intensity in the electromagnetic wave.

A machine tool includes a tool and a protective device. The tool includes a saw blade and a motor for driving the saw blade. An insulating member is arranged between the saw blade and the motor. The protective device includes a signal receiving unit, a control unit and a breaker. The signal receiving unit has an antenna receiving end that is in electrical contact with a middle region of the saw blade. The breaker is electrically connected between the motor and a utility power supply. The control unit is connected to the signal receiving unit and the breaker. The saw blade is used as an antenna by the signal receiving unit to receive an electromagnetic wave having the same frequency as that of a utility power from an environment, and the control unit controls the breaker according to a change of intensity in the electromagnetic wave.

A handheld power tool with a rotatable tool, in which the handheld power tool is a saw blade or milling cutter. The handheld power tool includes a sensor device for detecting a mechanical vector quantity. The mechanical vector quantity includes a force, an acceleration, a velocity, a deflection, a deformation and/or a mechanical stress and the mechanical vector quantity depends on a force emanating from the handheld tool. The handheld power tool also includes a control device which is communicatively coupled to the sensor device and is adapted to recognize an event and/or a state of the power tool according to a direction and/or change of direction of the mechanical vector quantity detected by the sensor device.

A self-dust extraction dustless table saw includes a table saw frame, saw table, and saw blade installed to the table saw frame. An upper and a lower blade guards are respectively mounted to upper and lower sides of the saw table, the saw blade is mounted in the upper and lower blade guards, and the lower blade guard includes a lower left and lower-right blade guards. Several interval guide barriers are installed on the inner walls of the lower left and lower right blade guards, and the guide barriers transport the dust to a dust outlet on the side of the lower right blade guard.

A self-dust extraction dustless table saw includes a table saw frame, saw table, and saw blade installed to the table saw frame. An upper and a lower blade guards are respectively mounted to upper and lower sides of the saw table, the saw blade is mounted in the upper and lower blade guards, and the lower blade guard includes a lower left and lower-right blade guards. Several interval guide barriers are installed on the inner walls of the lower left and lower right blade guards, and the guide barriers transport the dust to a dust outlet on the side of the lower right blade guard.

A method of detecting and mitigating kickback in a saw includes identification of a running average speed (RPM) of a saw blade, the speed at a given time sample relative to the running average speed, the percentage change in speed from one speed sample to the previous speed sample, and the percentage change in average speed based on the current speed of the saw blade. If the identified speed profile from the samples indicates a kickback is imminent, then the saw identifies an imminent kickback event and removes power from the saw motor to mitigate kickback.

A method of detecting and mitigating kickback in a saw includes identification of a running average speed (RPM) of a saw blade, the speed at a given time sample relative to the running average speed, the percentage change in speed from one speed sample to the previous speed sample, and the percentage change in average speed based on the current speed of the saw blade. If the identified speed profile from the samples indicates a kickback is imminent, then the saw identifies an imminent kickback event and removes power from the saw motor to mitigate kickback.

A miter saw includes a worktable and a cutting unit. The cutting unit includes a movable arm pivotably connected with the worktable, a saw blade, a triggering switch and a tilt power-off module. The movable arm defines a reference plane which intersects a working surface of the worktable at an included angle. The tilt power-off module is disposed to detect the included angle and shift the triggering switch between a power-on state and a power-off state. The triggering switch is shifted to the power-off state when the tilt power-off module detects that the included angle is less than a predetermined breaking angle so as to prevent rotation of the saw blade in a folded position for safety purposes.

A miter saw includes a worktable and a cutting unit. The cutting unit includes a movable arm pivotably connected with the worktable, a saw blade, a triggering switch and a tilt power-off module. The movable arm defines a reference plane which intersects a working surface of the worktable at an included angle. The tilt power-off module is disposed to detect the included angle and shift the triggering switch between a power-on state and a power-off state. The triggering switch is shifted to the power-off state when the tilt power-off module detects that the included angle is less than a predetermined breaking angle so as to prevent rotation of the saw blade in a folded position for safety purposes.