Centrifugal water pump systems are provided that can include: a chainsaw with a motor, a throttle, and a chainsaw bar; a water pump head with a suction pipe and a discharge pipe; and a coupling device configured to operably connect the chainsaw bar to the water pump head. Chainsaw accessories are also provided that can include a centrifugal pump configured to be coupled to the chainsaw bar. Chainsaw accessory kits are also provided that can include a centrifugal pump, stabilizer spikes, and a throttle control. Methods for using the chainsaws, pumps, and/or kits are also described.

A power-tool system includes at least one power-tool parting device including at least one cutting strand and at least one guide unit configured to guide the at least one cutting strand. The power tool system further includes at least one portable power tool including (i) a housing, (ii) a drive unit supported by the housing, (iii) at least one coupling device configured to operatively connect the at least one power-tool parting device to the drive unit, and (iv) at least one power-tool stabilization device including at least one stabilization element that is integrally formed with the housing and defines at least one support face configured to stabilize the at least one power-tool parting device.

A chainsaw guide bar adapted for carving and shaping a workpiece. In one embodiment, a guide bar includes a mounting end, a distal working end, and an intermediate portion offset from the longitudinal axis defined the mounting end. In one embodiment, the guide bar includes an axially elongated recess providing an unsupported span of chain which is movable between undeflected and deflected positions for contouring a workpiece. The chain is engaged with and supported in a guide rail slot along the top peripheral edge of the guide bar. Various embodiments of the guide bar have an asymmetrical shape. The guide bar may further include an idler sprocket mechanism operable to guide movement of the saw chain along the outer peripheral edge of the guide bar.

A chainsaw as a working machine, which switches among stop, drive, and choke operations of an internal combustion engine, includes an operation lever that is turnable, a turning member turnably combined with the operation lever, and a torsion coil spring holding abutting of the operation lever and the turning member. The turning member is coupled to a choke operating member via a choke rod and is regulated in turning from drive position to stop position. When the operation lever is turned from drive position to choke position, the turning member also turns to move the choke rod, by which the choke operating member closes the choke valve. Meanwhile, the operation lever is turned from drive position to stop position, against the turning force of the torsion coil spring.

A power tool (100), such as a chainsaw, comprising means (230) for driving said power tool (100) and a controller (210). The power tool comprises a movement sensor (220) and the controller (210) is configured to receive a signal from said movement sensor (220), determine if said signal is a signal indicating a movement, determine a time wherein no signal indicating a movement is received, determine if said time exceeds a time period, and if so, disable said driving means (230).

A customized arm supported safety device and a power cord attachment for an electrical appliance. Typical implementations of said attachment is for trimmers for a bush, a vacuum cleaner, an electric drill, or other power tool.

A trenching device rotating a trenching chain through a substrate to form a trench. The trenching device including a power unit, a drive unit including a belt drive system, and a trenching unit including a trenching chain and configured to rotate the trenching chain about a trenching bar.

A control system automates operations of a chainsaw mill. The chainsaw mill has at least one powerhead, and at least one travel motor that mechanically engages with a drive belt to drive the at least one powerhead along a guide track. A tension sensor measures tension on the drive belt, and a powerhead sensor produces a revolutions per minute (RPM) measurement of the at least one powerhead. A powerhead controller is responsive to the RPM measurement for controlling the powerhead's throttle to keep the RPM near a predetermined RPM setpoint. A travel motor controller is responsive to the tension measurement for controlling the at least one powerhead's transit speed along the guide track to maintain drive-belt tension near a predetermined tension setpoint.

A portable working machine includes a working machine body, bolt members erected on the working machine body, a cover member configured to be attachable to and detachable from the working machine body, in which the cover member has through-holes through which the bolt members are inserted when attaching the cover member, fixing members configured to be fastened to the bolt members to fix the cover member attached to the working machine body, and a holding member attached to an outer surface of the cover member with a predetermined gap space between the holding member and the outer surface of the cover member, in which the holding member is configured to retain the fixing members on an outer side of the outer surface of the cover member when a fastening of the fixing members to the bolt members is released to prevent the fixing members from dropping off the cover member.

A chainsaw includes a housing, a prime mover, a transmitting member and a bias assembly. The prime mover is mounted to the housing. The saw chain is driven by the prime mover. The guide bar guides the saw chain and the guide bar is slidably connected to the housing. The driving member drives the guide bar to slide relative to the housing. The operating member swings forth and back relative to the housing. The transmitting member enables the driving member to rotate synchronously with the operating member when the operating member is swung forth and enables the operating member to rotate relative to the driving member when the operating member is swung back. The bias assembly biases the transmitting member to engage with the operating member when the operating member is swung forth.