Abstract: An arrangement for attaching a bar of a hand-held motor driven tool, such as a chain saw, to a body of the tool includes at least one first engagement device, a cover portion adapted to bear against a bar such that the bar is arranged between the cover portion and the body, and at least one second engagement device is adapted to engage the first engagement device for securing a bar between the cover portion and the body. The second engagement device is arranged to move a first distance along the first engagement device in a direction of the rotation axis of the second engagement device for securing a bar between the cover portion and the body. The second engagement device is captively attached to a spring biasing member having an undistorted position and a distorted position.

Abstract: An arrangement for attaching a bar of a hand-held motor driven tool, such as a chain saw, to a body of the tool includes at least one first engagement device, a cover portion adapted to bear against a bar such that the bar is arranged between the cover portion and the body, and at least one second engagement device is adapted to engage the first engagement device for securing a bar between the cover portion and the body. The second engagement device is arranged to move a first distance along the first engagement device in a direction of the rotation axis of the second engagement device for securing a bar between the cover portion and the body. The second engagement device is captively attached to a spring biasing member having an undistorted position and a distorted position.

Abstract: A device for lubrication of a saw chain (23) where lubricant is provided from a lubrication pump and led through a first channel (12) that ends in a flat section (21) where the guide bar (22) is adjustably attached to the flat section (21). The end of the first channel (12) is shaped like a long cup (13) that is connected to the surface of the guide bar (22) and thereby making a tight seal between the first channel (12) and an inlet (25) placed inside the edges of the long cup shaped end (13) of the first channel (12) at the surface of the guide bar (22). The first channel (12) including the long cup-shaped end (13) is made of an elastic material to provide a tight seal between the first channel (12) and the surface of the guide bar (22).

Abstract: An automatic valve for reducing compression in order to facilitate starting of a two-stroke internal combustion engine includes a movable valve (25) adapted to control a gas flow through an opening (16) provided in a wall of the combustion chamber of the engine. A spring (27) is adapted to move the movable valve (25) to an open position, and a drive actuated by an underpressure is adapted to move the movable valve (25) to a closed position against the action of the spring (27). The driver includes a cylinder (18), a piston (19) movable in the cylinder (18) and connected to the movable valve (25), and a conduit (22) connecting the cylinder (18) to a source of underpressure. A one-way valve (23) is provided in the conduit (22) for allowing an air flow in a direction a way from the (18) only, and a leak passage (30) is adapted to allow a small flow of air into the (18) for facilitating the opening of the movable valve (25) when operation of the engine has been stopped.

Abstract: The present invention relates to a compression release valve (10;10';10";10'") for a combustion piston engine, said valve including a housing (12;12";12'") with a chamber (20;20';20'") having a passage (24;24";24'") in direct connection with the combustion chamber (22;22") of the engine and outlet means (26;26";26'") connected to the atmosphere or a space separated from the combustion chamber (22;22"). The compression release valve according to the present invention is characterized by being fully automatic. The function of the compression release valve is based on the fact that the valve includes elements of material having different coefficients of thermal expansion.

Abstract: An arrangement in an internal combustion engine comprises a membrane carbureter (10) having a fuel chamber (12) provided with a movable membrane (11) cooperating with a valve (17) for controlling the fuel supply to said fuel chamber. The air inlet of the carbureter is connected to a filter housing (31) provided with an air filter (32) for cleaning the inlet air, and a pressure chamber (13) is disposed adjacent said membrane and connected to said filter housing to control the fuel supply in relation to the pressure drop across said air filter (32). According to the invention, the membrane (11) is arranged in parallel with a wall (33) of the filter housing, and said wall is disposed adjacent to the pressure chamber (13) and provided with an opening (34) via which said pressure chamber communicates with the interior of said filter housing.