A quick tensioning system applicable to handheld chainsaws is provided wherein, during chain re-tensioning, the chain guiding bar remains firmly anchored to the bar holder and guiding means are provided to retract the motorized driving sprocket versus said guiding bar. The system includes a guide interposed between a stationary bar holding body and a motor body. This allows a linear or a rotation relative movement between the sliding driving sprocket and the stationary guiding bar. A drive is provided by means of a screw that an operator can easily operate via a knob conveniently mounted nearby the chainsaw handle.

A power-tool cutting device that is free of a torque-transmitting element includes at least one cutting strand and at least one guiding unit for guiding the cutting strand. The guiding unit together with the cutting strand forms a closed system. The power-tool cutting device has at least one preloading unit that is arranged on the guiding unit. The preloading unit is configured for automatic play compensation and/or tolerance compensation of the cutting strand at least during a state of the guiding unit in which the guiding unit is removed from a coupling device of a portable power tool.

A power-tool cutting device that is free of a torque-transmitting element includes at least one cutting strand and at least one guiding unit for guiding the cutting strand. The guiding unit together with the cutting strand forms a closed system. The power-tool cutting device has at least one preloading unit that is arranged on the guiding unit. The preloading unit is configured for automatic play compensation and/or tolerance compensation of the cutting strand at least during a state of the guiding unit in which the guiding unit is removed from a coupling device of a portable power tool.

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.

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.

A chain saw may include a saw chain, a guide bar to which the saw chain is attached, a sprocket configured to move the saw chain along a periphery of the guide bar, a prime mover configured to rotate the sprocket, a housing that houses the prime mover, a bolt protruding from the housing and penetrating a hole provided in the guide bar, and a nut screwed to the bolt to fix the guide bar to the housing. The nut may be exposed to outside. A heat insulating structure may be provided on a heat transfer path between the nut and the guide bar.

A chainsaw (100) includes a power unit and a working assembly powered responsive to operation of the power unit. The working assembly includes a guide bar (120) around which a chain is rotatable. The guide bar (120) includes a first side plate (200) and a second side plate (210) facing each other and extending away from the housing (110) to a nose of the guide bar (120), the first and second side plates (200 and 210) each including an inner sidewall (224 and 222) facing inwardly toward each other. Each of the inner sidewalls (224 and 222) includes a recessed portion (230) at which material of the inner sidewalls (224 and 222) has been removed.

A chain saw disclosed herein may include a motor configured to rotate a saw chain about a guide bar, a control unit configured to control a voltage applied to the motor, a body housing that houses the motor and the control unit, a battery detachably attached to the body housing, and a top handle provided above the body housing. The control unit may be disposed above the battery. In a rear view of the chain saw in a state where the chain saw is placed on a mount surface, the battery and the control unit may not overlap. In a top view of the chain saw in the state where the chain saw is placed on the mount surface, the battery and the control unit may overlap at least partially.

A chainsaw including a body including a bar stud extending therefrom; a guide bar including a bar stud slot that receives the bar stud, wherein the bar stud slot has a length, and wherein the guide bar is configured to receive a chain; a yoke having a groove defining a length extending in a direction angularly offset from the length of the bar stud slot of the guide bar, wherein the yoke is coupled to the guide bar; a ratchet gear including a one-way motion feature and a post extending into the groove of the yoke, wherein rotating the ratchet gear in a first direction moves the guide bar to tighten the chain, and wherein rotating the ratchet gear in a second direction moves the guide bar to loosen the chain; and a pawl selectively engaged with the one-way motion feature of the ratchet gear.

A chainsaw including a body including a bar stud extending therefrom; a guide bar including a bar stud slot that receives the bar stud, wherein the bar stud slot has a length, and wherein the guide bar is configured to receive a chain; a yoke having a groove defining a length extending in a direction angularly offset from the length of the bar stud slot of the guide bar, wherein the yoke is coupled to the guide bar; a ratchet gear including a one-way motion feature and a post extending into the groove of the yoke, wherein rotating the ratchet gear in a first direction moves the guide bar to tighten the chain, and wherein rotating the ratchet gear in a second direction moves the guide bar to loosen the chain; and a pawl selectively engaged with the one-way motion feature of the ratchet gear.