Abstract: A power tool is disclosed. The power tool may comprise a movable blade and a detection system for detecting contact between the blade and an object. The detection system may comprise an excitation plate capacitively coupling the drive signal to the movable blade and a circuit in communication with the excitation plate. The circuit may be configured to generate an in-phase component signal and a quadrature component signal from a blade current signal indicative of the instantaneous current drawn by the movable blade and calculate an energy of the blade current signal considering the in-phase component and the quadrature component. The circuit may be further programmed to compare the energy of the blade current signal to an adaptive trigger threshold to detect contact between the blade and the object based on whether the energy of the blade current signal is greater than the adaptive trigger threshold.

Abstract: A saw comprises a surface having an opening defined therein, a plate structure configured to be attached to the saw below the surface, and an arm pivotally attached to the plate structure about a first shaft. A blade is configured to be engaged with the arm at a location spaced from the first shaft. A portion of the blade extends through the opening when the saw is in a normal operating position. The saw comprises a firing mechanism comprising a barrel end portion having a bore defined therein and an extendable piston at least partially positioned within the bore. The barrel end portion is attached to the plate structure. The extendable piston engages the arm during its extension and causes the arm to pivot about the first shaft when the firing mechanism is activated by an activation signal. The pivoting of the arm causes the blade to be moved downwardly below the surface.

Abstract: In various embodiments, a saw can include a work surface and a blade at least partially extending through the work surface. In at least one embodiment, the saw can further include a sensor and a light emitter, wherein the light emitter can be configured to emit a first light beam and a second light beam onto at least a portion of the work surface. In various embodiments, the sensor can be can be configured to detect a plurality of saw conditions and, owing to communication between the sensor and the light emitter, the light emitter can be configured to emit the first light beam onto the work surface when the sensor detects a first saw condition and emit the second light beam onto the work surface when the sensor detects a second saw condition.

Abstract: In at least one form of the invention, a clamp can be used to attach a saw accessory to a saw. In various embodiments, the clamp can comprise first and second clamping members, an actuator, and a controller. In various embodiments, the saw accessory can be disposed between the first and second clamping members where at least one of the first and second clamping members can be moved by the actuator in order to clamp the saw accessory therebetween. In at least one such embodiment, the controller can be in electrical and/or fluid communication with the actuator to activate the actuator. In various embodiments, the controller can be activated by an operator from a location proximate to the operator but remote from a blade of the saw.

Abstract: In various embodiments, a saw accessory assembly can be configured to be attached to a saw. In at least one embodiment, the assembly can include a first component and a second component, wherein at least one of the first and second components can include a visual guide configured to assist an operator in assembling the first and second components. In other various embodiments, at least one of the first and second components can include a visual guide configured to assist the operator in adjusting the first and second components in a predetermined sequence.

Abstract: A power cutting tool having a movable blade, such as a table saw, comprising a radar sensing system for movement of an object in a region near the blade is disclosed. The radar sensing system emits a radio frequency wave and receives wave energy reflected by the object. The system measures the Doppler shift of the received wave energy to detect the presence of a fast moving object in a zone near the blade. When such a condition is detected, a reaction system can be activated to mitigate the condition.