A chain saw is provided with an adjustment mechanism that adjusts the tension of a saw chain 4 attached along a guide bar 3 projecting from a main body 2. The adjustment mechanism has a rotation shaft 55 that is provided with a feed screw, a moving element 70 that is moved on the rotation shaft 55 in an axial direction along with rotation of the rotation shaft 55 and moves the guide bar 3 forward/backward with respect to the main body 2, and a transmission mechanism including an internal gear 51 provided on an inner peripheral surface of an adjustment dial 50 rotatably provided on the main body 2 and an external gear 52 disposed on an inner side of the adjustment dial 50 and engaged with the internal gear 51. When the internal gear 51 is rotated along with rotation of the adjustment dial 50, the rotation shaft 55 is rotated via the external gear 52.

A chain saw is provided with an adjustment mechanism that adjusts the tension of a saw chain 4 attached along a guide bar 3 projecting from a main body 2. The adjustment mechanism has a rotation shaft 55 that is provided with a feed screw, a moving element 70 that is moved on the rotation shaft 55 in an axial direction along with rotation of the rotation shaft 55 and moves the guide bar 3 forward/backward with respect to the main body 2, and a transmission mechanism including an internal gear 51 provided on an inner peripheral surface of an adjustment dial 50 rotatably provided on the main body 2 and an external gear 52 disposed on an inner side of the adjustment dial 50 and engaged with the internal gear 51. When the internal gear 51 is rotated along with rotation of the adjustment dial 50, the rotation shaft 55 is rotated via the external gear 52.

A firewood processor with a tightenable saw chain, which processor comprises a frame arranged to support the firewood processor to a base, such as the ground, and a saw for sawing wood raw material in a transverse direction into an intermediate product of a desired length. The saw comprises a saw chain, a flange for guiding said saw chain and a sprocket, which is arranged to convey the driving force to said saw chain. The firewood processor further comprises a splitting section for splitting the intermediate product of a desired length in the longitudinal direction into a desired size, which splitting section comprises a splitting wedge and means for splitting the intermediate product of a desired length by means of the splitting wedge. In addition, the firewood processor comprises automatic means for tightening the saw chain of said saw and for maintaining the tightness.

A firewood processor with a tightenable saw chain, which processor comprises a frame arranged to support the firewood processor to a base, such as the ground, and a saw for sawing wood raw material in a transverse direction into an intermediate product of a desired length. The saw comprises a saw chain, a flange for guiding said saw chain and a sprocket, which is arranged to convey the driving force to said saw chain. The firewood processor further comprises a splitting section for splitting the intermediate product of a desired length in the longitudinal direction into a desired size, which splitting section comprises a splitting wedge and means for splitting the intermediate product of a desired length by means of the splitting wedge. In addition, the firewood processor comprises automatic means for tightening the saw chain of said saw and for maintaining the tightness.

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 bar unit for a wall saw is presented herein. The chain bar unit can include a bar configured to receive a circulating chain or wire around a perimeter of the bar. The chain bar unit also can include a driving gear for driving the chain or wire around the bar, the driving gear configured to be coupled to an output shaft of the wall saw. The chain bar unit further includes the bar being tapered from an end proximate to the driving gear to a distal end having a distal end radius, wherein a width of the bar at the proximate end, is at least two times the distal end radius of the distal end.

A chain bar unit for a wall saw is presented herein. The chain bar unit can include a bar configured to receive a circulating chain or wire around a perimeter of the bar. The chain bar unit also can include a driving gear for driving the chain or wire around the bar, the driving gear configured to be coupled to an output shaft of the wall saw. The chain bar unit further includes the bar being tapered from an end proximate to the driving gear to a distal end having a distal end radius, wherein a width of the bar at the proximate end, is at least two times the distal end radius of the distal end.

A chainsaw including: a housing; a motor supported by the housing, the motor comprising an output shaft; a guide bar, the guide bar defining a cutting track; a cutting implement guided by the cutting track and driven about the guide bar by rotation of the output shaft; a tension adjusting system for adjusting tension in the cutting implement by displacing the guide bar towards or away from the housing, the tension adjusting system comprising a user actuatable interface accessible from an exterior of the housing, wherein the user actuatable interface is a bistable movable between a first position and a second position, wherein the tension adjusting system tensions the cutting implement to a cutting tension when the user actuatable interface is in the first position, and wherein the tension adjusting system tensions the cutting implement to a relaxed tension when the user actuatable interface is in the second position.

A chainsaw including: a housing; a motor supported by the housing, the motor comprising an output shaft; a guide bar, the guide bar defining a cutting track; a cutting implement guided by the cutting track and driven about the guide bar by rotation of the output shaft; a tension adjusting system for adjusting tension in the cutting implement by displacing the guide bar towards or away from the housing, the tension adjusting system comprising a user actuatable interface accessible from an exterior of the housing, wherein the user actuatable interface is a bistable movable between a first position and a second position, wherein the tension adjusting system tensions the cutting implement to a cutting tension when the user actuatable interface is in the first position, and wherein the tension adjusting system tensions the cutting implement to a relaxed tension when the user actuatable interface is in the second position.

A chain saw, arranged with a guide plate and a chain. The chain saw includes a housing, a drive assembly arranged in the housing, and a fixing assembly tensioning the chain and locking the guide plate. The fixing assembly includes a shield abutting against the guide plate, a knob arranged on an outside of the shield, a tensioning member driven by the knob, a locking member snapped to the shield, and an elastic member disposed between the knob and the locking member. A side of the shield facing the locking member is arranged with a first clamping part, and a side of the locking member facing the shield is arranged with a second clamping part; in condition of the guide plate being locked, the elastic member deforms and abuts against the locking member, causing the second clamping part to snapped to the first clamping part.