Abstract: A guide bar for a chain saw has an elongate main body of steel. The main body has flat sides and upper and lower peripheries defining a guide groove for a saw chain. An elongate window is formed in the main body between the peripheries and is filled with an insert made of a fiber composite material made up of resin and fibers. The fibers are in the direction of the longitudinal axis of the main body. The insert includes a plurality of fiber layers that are bonded with resin. A central layer is formed from a fiber layer and the fibers thereof are at an angle to the longitudinal axis. Two fiber layers having fibers oriented in the direction of the longitudinal axis of the main body are on both sides of the central layer. The inner fiber layers are covered outwardly by a woven fabric.

Abstract: A guide bar for a chain saw has an elongate main body of steel. The main body has flat sides and upper and lower peripheries defining a guide groove for a saw chain. An elongate window is formed in the main body between the peripheries and is filled with an insert made of a fiber composite material made up of resin and fibers. The fibers are in the direction of the longitudinal axis of the main body. The insert includes a plurality of fiber layers that are bonded with resin. A central layer is formed from a fiber layer and the fibers thereof are at an angle to the longitudinal axis. Two fiber layers having fibers oriented in the direction of the longitudinal axis of the main body are on both sides of the central layer. The inner fiber layers are covered outwardly by a woven fabric.

Abstract: A protective cover of a hand-held cut-off machine has a bracket that is secured on the exterior side of the protective cover. The bracket is locked in at least one locked position with at least one locking projection in at least one receptacle of the protective cover. The bracket is releasable from the locked position by a movement of the bracket in the release direction. A simple release of the bracket can be achieved in that the protective cover has means that move the locking projection upon movement of the bracket in the release direction at least partially out of the receptacle.

Abstract: A protective cover of a hand-held cut-off machine has a bracket that is secured on the exterior side of the protective cover. The bracket is locked in at least one locked position with at least one locking projection in at least one receptacle of the protective cover. The bracket is releasable from the locked position by a movement of the bracket in the release direction. A simple release of the bracket can be achieved in that the protective cover has means that move the locking projection upon movement of the bracket in the release direction at least partially out of the receptacle.

Abstract: At least one transfer channel (9, 29) is formed in the cylinder wall (4, 24) of the cylinder (1, 21) for a two-stroke engine. The transfer channel (9, 29) is closed to the cylinder outer side (5, 25) by a cover (10, 30). The method for making the cylinder (1, 21) provides that the cover (10, 30) is assembled in a first step on the cylinder (1, 21) and, in a second step, the cylinder bore (3, 23) is machined.

Abstract: A manually guided implement driven by an internal combustion engine having a carburetor that is actuated by a throttle lever arrangement, which includes a throttle lever that is mounted in the implement so as to be pivotable about a pivot axis, and also includes a transmission element that operatively connects the throttle lever with the carburetor. The transmission element is an essentially rigid connecting rod that is mounted on the throttle lever and on an actuating lever of the carburetor.

Abstract: A cylinder housing (1) is cast with a cylinder wall (2) in the making of a cylinder for an internal combustion engine. The cylinder wall delimits an interior space (3) for accommodating a reciprocating piston and, thereafter, a control window (5) is machined into the cylinder wall (2) as an opening of a transfer channel (4) into the interior space (3). A two-stage machining for forming the control window (5) is provided in order to make possible a rapid and cost effective manufacture of the cylinder. In a first step with a work tool (7) having a rotating primary movement (11), a breakthrough (10) is machined into the cylinder wall (2) and, in a second step with a work tool, the breakthrough (10) is widened to the wanted dimensions of the control window (5).

Abstract: A manually guided implement driven by an internal combustion engine having a carburetor that is actuated by a throttle lever arrangement, which includes a throttle lever that is mounted in the implement so as to be pivotable about a pivot axis, and also includes a transmission element that operatively connects the throttle lever with the carburetor. The transmission element is an essentially rigid connecting rod that is mounted on the throttle lever and on an actuating lever of the carburetor.

Abstract: A two-cycle engine is provided that has a cylinder in which is formed a combustion chamber delimited by a reciprocating piston that via a connecting rod drives a crankshaft rotatably mounted in a crankcase. An inlet is provided for a supply of fuel into the crankcase, and an outlet leads out of the combustion chamber. In predetermined positions of the piston the crankcase communicates with the combustion chamber via at least one transfer channel. The cover is secured to a connecting flange of the cylinder, the cover closes off the transfer channel on an outer side of a cylinder, the connecting flange is inclined relative to the longitudinal axis of the cylinder by an angle that opens in a direction toward the crankcase.

Abstract: A two-cycle engine is provided and includes a cylinder in which is formed a combustion chamber delimited by a reciprocating piston that via a connecting rod drives a crankshaft rotatably mounted in a crankcase that, in predetermined positions of the piston, communicates with the combustion chamber via transfer channels. The cylinder has an outlet from the combustion chamber. An intake duct leads into the crankcase for a supply of fuel, and an air duct supplies substantially fuel-free air. In the vicinity of the piston the air duct is divided into two branches that open out at air openings of a connecting flange formed on the cylinder. A cover is disposed on the connecting flange and extends over the air openings. A flow divider on the connecting flange projects beyond a plane thereof and into the cover. The flow divider divides an air flow in the air duct to the two branches.

Abstract: A two-cycle engine is provided, especially in a manually-guided implement such as a power chain saw, a brush cutter, a trimmer or the like, and has a cylinder in which is formed a combustion chamber that is delimited by a reciprocating piston that, via a connecting rod, drives a crankshaft that is rotatably mounted in a crankcase. In prescribed positions of the piston, the combustion chamber is connected with the crankcase via at least two transfer channels. At least one air channel is provided that opens out at an air channel window at the cylinder in the region of the piston, and that, in prescribed positions of the piston, is connected with at least two transfer channels via a piston window formed in the piston. To achieve a good scavenging of the combustion chamber, and hence low exhaust gas values of the engine, structural features are provided on the piston window for the defined distribution of air to the transfer channels.

Abstract: A cylinder housing (1) is cast with a cylinder wall (2) in the making of a cylinder for an internal combustion engine. The cylinder wall delimits an interior space (3) for accommodating a reciprocating piston and, thereafter, a control window (5) is machined into the cylinder wall (2) as an opening of a transfer channel (4) into the interior space (3). A two-stage machining for forming the control window (5) is provided in order to make possible a rapid and cost effective manufacture of the cylinder. In a first step with a work tool (7) having a rotating primary movement (11), a breakthrough (10) is machined into the cylinder wall (2) and, in a second step with a work tool, the breakthrough (10) is widened to the wanted dimensions of the control window (5).

Abstract: A two-cycle engine is provided, especially in a manually-guided implement such as a power chain saw, a brush cutter, a trimmer or the like, and has a cylinder in which is formed a combustion chamber that is delimited by a reciprocating piston that, via a connecting rod, drives a crankshaft that is rotatably mounted in a crankcase. In prescribed positions of the piston, the combustion chamber is connected with the crankcase via at least two transfer channels. At least one air channel is provided that opens out at an air channel window at the cylinder in the region of the piston, and that, in prescribed positions of the piston, is connected with at least two transfer channels via a piston window formed in the piston. To achieve a good scavenging of the combustion chamber, and hence low exhaust gas values of the engine, structural features are provided on the piston window for the defined distribution of air to the transfer channels.

Abstract: A two-stroke engine having a combustion chamber (3) configured in a cylinder (2) is disclosed. The combustion chamber is delimited by a reciprocating piston (5). The two-stroke engine includes at least one transfer channel (10, 11) configured in the cylinder and fluidly connecting the combustion chamber and a crankcase (4). The transfer channel is delimited by a set wall (19) with respect to the interior space (18) of the cylinder at least over a portion of its longitudinal extent. The set wall may be held with respect to the interior space of the cylinder by a device configured with the cylinder as one part. A method for manufacturing the two-stroke engine provides that the cylinder is produced in the pressure-cast die process and a set wall is pushed into the cylinder between the cylinder interior space and the transfer channels and is thereafter fixed via a holding element.

Abstract: At least one transfer channel (9, 29) is formed in the cylinder wall (4, 24) of the cylinder (1, 21) for a two-stroke engine. The transfer channel (9, 29) is closed to the cylinder outer side (5, 25) by a cover (10, 30). The method for making the cylinder (1, 21) provides that the cover (10, 30) is assembled in a first step on the cylinder (1, 21) and, in a second step, the cylinder bore (3, 23) is machined.

Abstract: A two-cycle engine is provided and includes a cylinder in which is formed a combustion chamber delimited by a reciprocating piston that via a connecting rod drives a crankshaft rotatably mounted in a crankcase that, in predetermined positions of the piston, communicates with the combustion chamber via transfer channels. The cylinder has an outlet from the combustion chamber. An intake duct leads into the crankcase for a supply of fuel, and an air duct supplies substantially fuel-free air. In the vicinity of the piston the air duct is divided into two branches that open out at air openings of a connecting flange formed on the cylinder. A cover is disposed on the connecting flange and extends over the air openings. A flow divider on the connecting flange projects beyond a plane thereof and into the cover. The flow divider divides an air flow in the air duct to the two branches.

Abstract: A two-cycle engine is provided that has a cylinder in which is formed a combustion chamber delimited by a reciprocating piston that via a connecting rod drives a crankshaft rotatably mounted in a crankcase. An inlet is provided for a supply of fuel into the crankcase, and an outlet leads out of the combustion chamber. In predetermined positions of the piston the crankcase communicates with the combustion chamber via at least one transfer channel. The cover is secured to a connecting flange of the cylinder, the cover closes off the transfer channel on an outer side of a cylinder, the connecting flange is inclined relative to the longitudinal axis of the cylinder by an angle that opens in a direction toward the crankcase.

Abstract: A two-stroke engine, especially for a portable handheld work apparatus, has a combustion chamber (3) configured in a cylinder (2). The combustion chamber is delimited by a reciprocating piston (5). The two-stroke engine (1) includes at least one transfer channel (10, 11) which is configured in the cylinder (2) and this transfer channel fluidly connects the combustion chamber (3) and a crankcase (4) at pregiven positions of the piston. The transfer channel (10, 11) is delimited by a set wall (19) with respect to the interior space (18) of the cylinder at least over a portion of its longitudinal extent. In order to provide for a simple manufacture of the two-stroke engine (1), the set wall (19) is held with respect to the interior space (18) of the cylinder by a device configured with the cylinder (2) as one part.

Abstract: The invention relates to a portable handheld work apparatus such as a motor-driven chain saw, a cutoff machine, a brushcutter or the like. The work apparatus includes an internal combustion engine (1) mounted in a housing (2) which drives a work tool via centrifugal clutch (3). The centrifugal clutch (3) includes a carrier (5) driven by the engine (1). The carrier (5) has rpm-dependent displaceable centrifugal weights (6) which are displaceable against a return force and come into contact engagement against a contact wall (7) of an output part (8) so as to transmit-torque. A rotationally-elastic damping element (11) is arranged between the output part (8) and an intermediate element (10) connected to the tool (4) so as to rotate with the intermediate element (10).

Abstract: The invention relates to a portable handheld work apparatus such as a motor-driven chain saw, a cutoff machine, a brushcutter or the like. The work apparatus includes an internal combustion engine (1) mounted in a housing (2) which drives a work tool via centrifugal clutch (3). The centrifugal clutch (3) includes a carrier (5) driven by the engine (1). The carrier (5) has rpm-dependent displaceable centrifugal weights (6) which are displaceable against a return force and come into contact engagement against a contact wall (7) of an output part (8) so as to transmit torque. A rotationally-elastic damping element (11) is arranged between the output part (8) and an intermediate element (10) connected to the tool (4) so as to rotate with the intermediate element (10).