A chain saw may include a saw chain, a guide bar to which the saw chain is attached, a sprocket configured to run the saw chain along a periphery of the guide bar, a prime mover configured to rotate the sprocket, an oil tank configured to store oil to be supplied to the saw chain, a housing that houses the prime mover and the oil tank, a bolt protruding from the housing and penetrating a hole disposed in the guide bar, a nut screwed onto the bolt to fix the guide bar to the housing, and a heat dissipating structure configured to dissipate heat from the bolt to the oil in the oil tank.

Mobile assembly for cutting wood includes a base supported by wheels, and a plurality of posts extending upwards from the base. A frame is removably coupled to a distal post and a proximal post. The frame configured to pivot relative to at least one of the distal and proximal posts when coupled thereto, the frame configured for positioning at different heights along the at least one of the distal and proximal posts. An arm is supported by the frame, the arm configured for sliding about, and parallel to, the frame. The arm includes a chainsaw attached to a distal region of the arm.

A power tool includes a switch moveable between a first position enabling activation of a motor and a second position disabling the motor. The power tool includes a trigger movably coupled to a housing of the power tool between an OFF position and an ON position. The switch moves from the second position to the first position in response to the trigger moving from the OFF position to the ON position. The power tool includes a trigger lock-off pivotably coupled to the housing between a lock position and an unlock position. The trigger lock-off is engageable with the trigger to inhibit movement of the trigger from the OFF position to the ON position when the trigger lock-off is in the lock position. The trigger lock-off allows movement of the trigger from the OFF position to the ON position when the trigger lock-off is in the unlock position.

A power tool includes a switch moveable between a first position enabling activation of a motor and a second position disabling the motor. The power tool includes a trigger movably coupled to a housing of the power tool between an OFF position and an ON position. The switch moves from the second position to the first position in response to the trigger moving from the OFF position to the ON position. The power tool includes a trigger lock-off pivotably coupled to the housing between a lock position and an unlock position. The trigger lock-off is engageable with the trigger to inhibit movement of the trigger from the OFF position to the ON position when the trigger lock-off is in the lock position. The trigger lock-off allows movement of the trigger from the OFF position to the ON position when the trigger lock-off is in the unlock position.

A chainsaw 1 (electric-power-driven working device) comprises a body case 10, a cutting attachment 20 (work tool), a motor 30 and a battery 90. A front portion 11a of the body case 10 houses the motor 30 and a battery mount-and-release portion 12 is formed on a rear portion 11b of the body case 10. The battery 90 mounted on the battery mount-and-release portion 12 extends in an upper-lower direction across and over a middle portion in a height direction of the rear portion 11b of the body case 10. The side handle 50 arranged to a side face of the body case 10 extends from the front portion 11a to the rear portion 11b of the body case 10. A rear end portion 52 of the side handle is disposed rearward of and below an output shaft 31 of the motor 30.

A sprocket arrangement (5) for a handheld power tool such as a saw, comprising a drive unit configured to rotate a drive shaft and cutting tool configured to be driven by the drive shaft (21) via the sprocket arrangement. The sprocket arrangement (5) comprises a gear (1) and at least one flexible element (6a, 6b) arranged such that the drive shaft (21) in the handheld power tool is resiliently connected to the cutting tool in the handheld power tool. A handheld power tool comprising a drive unit, a drive shaft, driving means, and a sprocket arrangement is also provided.

A sprocket arrangement (5) for a handheld power tool such as a saw, comprising a drive unit configured to rotate a drive shaft and cutting tool configured to be driven by the drive shaft (21) via the sprocket arrangement. The sprocket arrangement (5) comprises a gear (1) and at least one flexible element (6a, 6b) arranged such that the drive shaft (21) in the handheld power tool is resiliently connected to the cutting tool in the handheld power tool. A handheld power tool comprising a drive unit, a drive shaft, driving means, and a sprocket arrangement is also provided.

In a combination of a sprocket arrangement (128) and a saw chain (16), a sprocket tooth spacing (T1) between consecutive sprocket teeth (40) relates to a drive link spacing between consecutive drive links (30) of the saw chain (16) such that the guide teeth (42) of two or more drive links (30) may enter between a pair of consecutive sprocket teeth (40).

In a combination of a sprocket arrangement (128) and a saw chain (16), a sprocket tooth spacing (T1) between consecutive sprocket teeth (40) relates to a drive link spacing between consecutive drive links (30) of the saw chain (16) such that the guide teeth (42) of two or more drive links (30) may enter between a pair of consecutive sprocket teeth (40).

A method is provided for operating a hand-guided processing device that has a rotating and/or circulating cutting tool, an electric motor drive system wherein the electric motor drive system is configured for generating a torque for driving the cutting tool, and a user-operable control element. The method automatically monitors whether a blocking criterion is fulfilled, wherein the blocking criterion is characteristic of a blocking of the cutting tool, and if the blocking criterion is fulfilled and the control element operated, automatically lowers the torque generated by the electric motor drive system, and temporally thereafter, automatically increases the torque generated by the electric motor drive system.