A blade sharpening system may include a sharpening tool for sharpening a workpiece. The system may also include a sharpening fixture having a mounting surface for mounting a workpiece to be sharpened by the sharpening tool. The mounting surface may be disposed on a sled that is movable along a sharpening path that passes under a sharpening implement that may be mounted to a movable arm of the sharpening tool when the arm is in an engaged position. The movement of the sled may be coupled to the movement of the arm such that moving the arm from a disengaged position to the engaged position initiates the sled to move in a first direction along the sharpening path and moving the arm from the engaged position to the disengaged position initiates the sled to move along the sharpening path in a second direction.

A twin-head bar cutting device includes a first cutting head and a first bar holding device as well as a second cutting head and a second bar holding device placed on a common base. The base includes a first placement surface on which the first cutting head is placed, a second placement surface on which the second cutting head is placed, and a holding device placement surface formed higher than the first placement surface and the second placement surface between the first placement surface and the second placement surface and on which the first bar holding device and the second bar holding device are placed, and the first cutting head and the second cutting head are arranged symmetrically about a vertical plane passing through a center in a width direction of the base.

A power tool assembly includes a drop arm assembly movable along a drop path between a first drop arm assembly position whereat a portion of a shaping device supported by the drop arm assembly extends above a workpiece support surface and a second drop arm assembly position whereat the portion of the shaping device does not extend above the workpiece support surface, an actuator housing configured to house a first actuating device at an active location at which a force from the first actuating device is transferred to the drop arm assembly, the actuator housing including a slit configured to position a second actuating device at an inactive location, and a control system configured such that when the first actuating device is housed, the control system controls the first actuating device to transfer the force to the drop arm assembly when an unsafe condition is sensed.

A power tool assembly includes a drop arm assembly movable along a drop path between a first drop arm assembly position whereat a portion of a shaping device supported by the drop arm assembly extends above a workpiece support surface and a second drop arm assembly position whereat the portion of the shaping device does not extend above the workpiece support surface, an actuator housing configured to house a first actuating device at an active location at which a force from the first actuating device is transferred to the drop arm assembly, the actuator housing including a slit configured to position a second actuating device at an inactive location, and a control system configured such that when the first actuating device is housed, the control system controls the first actuating device to transfer the force to the drop arm assembly when an unsafe condition is sensed.

A safety system is provided for a machine tool which has a frame and a tool. The safety system has a clamping device and a motion device. The clamping device is movable by the motion device from a working position, in which the tool is extended and can be used for working, to a safety position, in which the tool is retracted. The motion device has a first magnetic means connected to or arranged on the tool and a second magnetic means connected to or arranged on the frame, such that movement of the tool by the motion device from the working position to the safety position can be triggered and/or at least partially performed by magnetic force.

A wet cutting saw for cutting a ground portion, the wet cutting saw including a blade rotatable about an axis, a liquid feed conduit for feeding liquid onto a surface of the blade as it rotates, a frame for carrying the blade and configured to travel over a surface of the ground portion, and a mounting assembly that mounts the blade to the frame, at least part of the mounting assembly pivotable relative to the frame to raise and lower the blade relative to the frame.

A wet cutting saw for cutting a ground portion, the wet cutting saw including a blade rotatable about an axis, a liquid feed conduit for feeding liquid onto a surface of the blade as it rotates, a frame for carrying the blade and configured to travel over a surface of the ground portion, and a mounting assembly that mounts the blade to the frame, at least part of the mounting assembly pivotable relative to the frame to raise and lower the blade relative to the frame.

A blade sharpening system may include a sharpening tool for sharpening a workpiece. The system may also include a sharpening fixture having a mounting surface for mounting a workpiece to be sharpened by the sharpening tool. The mounting surface may be disposed on a sled that is movable along a sharpening path that passes under a sharpening implement that may be mounted to a movable arm of the sharpening tool when the arm is in an engaged position. The movement of the sled may be coupled to the movement of the arm such that moving the arm from a disengaged position to the engaged position initiates the sled to move in a first direction along the sharpening path and moving the arm from the engaged position to the disengaged position initiates the sled to move along the sharpening path in a second direction.

Machines with safety systems are disclosed. The machine may take the form of woodworking machines including table saws, band saws, miter saws, hand-held circular saws, pneumatic chop saws, radial-arm saws, jointers, planars, routers and shapers. The machines may include an operative structure configured to perform a task, where the operative structure includes a cutting tool adapted to move in at least one motion, and a safety system adapted to detect the occurrence of an unsafe condition between a person and the cutting tool and for mitigating the unsafe condition. The safety system may include a detection subsystem and a reaction subsystem.

A power tool used to perform a coping cut including a main housing, a motor disposed within the main housing, a drive shaft driven by the motor about a rotational axis, a handle extending from the main housing, and an abrasive disc coupled to and driven by the drive shaft about the rotational axis. The motor is an outer rotor brushless direct current motor capable of rotating at 4,000 surface feet per minute at 1.5 inch-pounds of torque.