A chainsaw may include a saw chain; a guide bar, a sprocket, a prime mover, a housing, a sprocket cover, and a guide member. The guide bar, the housing and the sprocket cover may define a chain passage. The guide member may include a first facing surface having an arc shape centered on the rotation axis and a second facing surface having an arc shape centered on a position offset from the rotation axis. When the chainsaw is placed on a horizontal mounting surface and viewed in the direction along the rotation axis, an angle between (i) a straight line connecting the rotation axis and a position where the first facing surface and the second facing surface are connected and (ii) a horizontal plane may be in a range of −10 degrees to 25 degrees.

A chainsaw may include a saw chain; a guide bar, a sprocket, a prime mover, a housing, a sprocket cover, and a guide member. The guide bar, the housing and the sprocket cover may define a chain passage. The guide member may include a first facing surface having an arc shape centered on the rotation axis and a second facing surface having an arc shape centered on a position offset from the rotation axis. When the chainsaw is placed on a horizontal mounting surface and viewed in the direction along the rotation axis, an angle between (i) a straight line connecting the rotation axis and a position where the first facing surface and the second facing surface are connected and (ii) a horizontal plane may be in a range of −10 degrees to 25 degrees.

A method and apparatus are provided for vertically felling trees by taking apart the trunk in a stepwise manner combining sagittal and horizontal cross-sections. A vertical frame is attachable to a tree trunk, the vertical frame having a movable portion and a fixed portion. A first cutting device is attachable to the vertical frame and configured to cut the tree sagittally substantially along a longitudinal axis of the tree. A second cutting device is attachable to the vertical frame and configured to cut the tree horizontally from an exterior of the tree to a sagittal cut made in the tree by the first cutting device. A locking mechanism releasably locks the movable portion of the frame to the fixed portion of the frame. The apparatus uses the weight of the upper trunk to maintain stability to steadily decrease the tree height until the entire tree is removed.

A method and apparatus are provided for vertically felling trees by taking apart the trunk in a stepwise manner combining sagittal and horizontal cross-sections. A vertical frame is attachable to a tree trunk, the vertical frame having a movable portion and a fixed portion. A first cutting device is attachable to the vertical frame and configured to cut the tree sagittally substantially along a longitudinal axis of the tree. A second cutting device is attachable to the vertical frame and configured to cut the tree horizontally from an exterior of the tree to a sagittal cut made in the tree by the first cutting device. A locking mechanism releasably locks the movable portion of the frame to the fixed portion of the frame. The apparatus uses the weight of the upper trunk to maintain stability to steadily decrease the tree height until the entire tree is removed.

A guide bar for motor chainsaws has side plates and a middle section between the side plates connected fixedly and non-movably to the side plates. The side plates form a clamping section and a deflection section opposite the clamping section. A guide groove extends circumferentially about the guide bar. The middle section forms the guide groove bottom in the deflection section. A guide bar tip is located where the longitudinal center axis of the guide bar intersects the deflection section. The side plates each have a guide surface extending continuously across a first longitudinal side of the guide bar, the deflection section, and a second longitudinal side of the guide bar. The guide surfaces of the side plates have hardened regions at the first and second longitudinal sides and at the guide bar tip with a hardness greater than a hardness of a middle region of the side plates.

A guide bar for motor chainsaws has side plates and a middle section between the side plates connected fixedly and non-movably to the side plates. The side plates form a clamping section and a deflection section opposite the clamping section. A guide groove extends circumferentially about the guide bar. The middle section forms the guide groove bottom in the deflection section. A guide bar tip is located where the longitudinal center axis of the guide bar intersects the deflection section. The side plates each have a guide surface extending continuously across a first longitudinal side of the guide bar, the deflection section, and a second longitudinal side of the guide bar. The guide surfaces of the side plates have hardened regions at the first and second longitudinal sides and at the guide bar tip with a hardness greater than a hardness of a middle region of the side plates.

A stop has an elongate form between a base and a tip, with the base configured to be attachable to a chainsaw bar closer to a free end of the bar then to a housing of the chainsaw to which the bar is mounted. The stop extends below a lower edge of the bar. Bolts or other fasteners pass through holes in the stop and through holes in the bar for attachment. Positioning of the stop separates a tip space from a main space where chain teeth can cut wooden material. Smaller branches can conveniently be cut in the tip space while larger wooden material can be cut in the main space. The stop is configured to include clearance for the chain to pass thereby, such as by including standoffs in the stop adjacent to holes at the base, or by providing a clearance groove or clearance bend.

A stop has an elongate form between a base and a tip, with the base configured to be attachable to a chainsaw bar closer to a free end of the bar then to a housing of the chainsaw to which the bar is mounted. The stop extends below a lower edge of the bar. Bolts or other fasteners pass through holes in the stop and through holes in the bar for attachment. Positioning of the stop separates a tip space from a main space where chain teeth can cut wooden material. Smaller branches can conveniently be cut in the tip space while larger wooden material can be cut in the main space. The stop is configured to include clearance for the chain to pass thereby, such as by including standoffs in the stop adjacent to holes at the base, or by providing a clearance groove or clearance bend.

An electric work machine (1) includes: a brushless motor having a stator disposed around a rotor (30); and an output part driven by the rotor. The rotor has a rotor core (31) and first and second magnetic-pole parts (34S, 34N) disposed around a circumferential direction of the rotor core. When the induced voltage of the brushless motor is given as Va, the power-supply voltage of the brushless motor is given as Vb, the rotational speed of the brushless motor is given as ω, a first induced voltage constant, which is expressed by Va/ω, is given as Ea [V/krpm], a pole-pairs count, which is the number of the first magnetic-pole parts or the second magnetic-pole parts, is given as Pi, and a second induced voltage constant, which is expressed as Ea/Pi, is given as Eb [V/krpm pole-pairs count], the motor satisfies the condition: Eb≤0.025×Vb.

A handheld cutting tool includes a motor, a driven gear coupled to the motor for receiving torque therefrom and a sprocket coupled for co-rotation with the driven gear, a handle guard extending from handle portion, a chain supported on a guide bar and engaged with the sprocket such that rotation of the sprocket moves the chain along the guide bar, and a battery pack removably coupled to an end of the handle portion. The handle guard includes a support face configured to support the handheld cutting tool on a horizontal support surface, and the battery pack includes a foot portion. A center of gravity of the handheld cutting tool is located above the foot portion and permits balancing of the handheld cutting tool in an upright position on only the foot portion.