Dolmar Gmbh

Christian Kellermann

Klemens Krahn

An exhaust system for an internal combustion engine includes an outer housing having a front shell and a rear shell, a prechamber in which exhaust gas from the combustion chamber enters, and an intermediate shell having a front and back as well as a catalytic converter holder. A catalytic converter element is arranged on the catalytic converter holder where an exhaust port directs exhaust gas from the catalytic converter element. To place the center of gravity of the exhaust system near the internal combustion engine or cylinder, the intermediate shell forms the prechamber and the exhaust port.

Multiple-shell silencer / rear shell port

The invention pertains to a device for starting an internal combustion engine for handheld equipment such as chain saws, lawn mowers, lawn trimmers and the like, or for vehicles such as mopeds, boats or miniature aircraft. The starting device features an output element into which a starter torque can be introduced when the starting device is actuated. The output element is functionally connected to a crankshaft of the internal combustion engine in order to introduce a crankshaft torque therein. The functional connection between the output element and the crankshaft introduces variable crankshaft torque into the crankshaft depending on the rotational angle of the crankshaft at a constant starter torque. This advantageously improves force or torque characteristics for largely operating the starter device independently of the compression phase and the expansion phase of the internal combustion engine.

Starter device for a motor driven machine

A silencer for a two-stroke engine includes a first chamber and a second chamber, wherein a flow channel is provided between an outlet of a combustion chamber and the first chamber. A high charge degree of the combustion chamber has a pressure ratio in the region of the outlet which reduces or prevents an escape of fresh gas from the combustion chamber. The flow channel between the outlet and the first chamber is flow-favorably shaped in such a manner that the exhaust gas that flows out of the outlet because of its mass inertia predominantly flows into the first chamber and following charging of the first chamber flows back again and as a result a back pressure is formed in the direction of the combustion chamber.

Silencer for a motor device

A device for starting an internal combustion engine for hand-held tools, chainsaws, lawnmowers, trimmers and the like, includes a rotatable pulling medium roller which can be brought into functional connection with the crankshaft of the internal combustion engine in order to bring about a rotation of the crankshaft. The starting device has a simply configured functional connection between the crankshaft and the pulling medium roller and effectively reduces the force peaks reaching the pulling medium roller. To accomplish this, a deformation body having elastic deformation behaviour is arranged in the functional connection between the pulling medium roller and the crankshaft. The deformation body compensates for leading or lagging of the crankshaft with respect to the pulling medium roller.

Starter device for an engine unit with improved damping

A suction device for a cyclone filter of a hand-guided work apparatus includes a blower which is located in a housing and a starting unit with a cable drum which is rotatably mounted about an axis, wherein ambient air sucked in with dirt particles is divided by the cyclone filter into a first air stream which is largely freed from dirt particles and into a second air stream loaded with dirt particles. The housing has an inlet and an outlet for the second air stream, which has a simple configuration and a good suction performance for air laden with dirt particles. The blower is mounted rotatably about an axis which is arranged coaxially to the cable drum axis and the housing is designed with a channel which is connected to the inlet and opens in the region of the cable drum axis.

Suction device

In order to make available an exhaust gas system for a combustion engine with an external housing, which contains at least one rear shell and one front shell, and with a catalyst chamber, in which at least one catalyst element is arranged, and with an exhaust gas duct, from which exhaust gas is conveyed from the catalyst chamber, said exhaust gas system including few components and being able to be produced cost-effectively and wherein harmful thermal stresses in the components of the exhaust gas system are largely avoided, the catalyst chamber also forms the exhaust gas duct. The catalyst chamber has at least two chamber halves, and the exhaust gas duct is provided materially uniform and in one piece in at least one chamber half.

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Stapelfeld, Germany

Christian Kellermann