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In frame sawing machines, where a saw frame is driven by a crank mechanism, an inertial force produced by the saw frame cyclic motion significantly affects the machine foundation and also the saw frame driving system. This paper discusses the question how these serious using difficulties in machine performance can be eliminated. The authors present the principle of operation of the hybrid dynamically balanced saw frame driving system with the kinetic energy accumulator connected in parallel. The findings of numerical analysis are: this solution allows us to eliminate changing loads of the driving system and permits a reduction of the mass and dimensions of the machine, to eliminate a huge and expensive foundation, and to increase the working speed. Dynamisches Auswuchten von Kreissägeantrieben bei GattersägenSägegatter, die über Kurbelwellen angetrieben werden, sind Trägheitskräften unterworfen, die durch die Kreisbewegungen hervorgerufen werden. Die Trägheitsmo-mente übertragen sich sowohl auf die Sägefundamente als auch auf das Antriebssystem. In dieser Arbeit wird diskutiert, wie diese Schwierigkeiten ausgeschaltet werden können. Vorgestellt wird das Prinzip eines dynamisch ausgewuchteten Antriebsystems des Gatters mit einem parallelgeschalteten Energieakkumulator. Die Ergebnisse der numerischen Analyse besagen: Diese Lösung ermög-licht es, wechselnde Belastungen des Antriebssystems auszuschalten. Weiterhin besteht dadurch die Möglichkeit, die Masse und Abmessungen der Maschine zu verringern. Infolgedessen ergeben sich Einsparungen an starken und teuren Fundamenten, und die Arbeitsgeschwindigkeit kann erhöht werden. NomenclatureA accumulator (a flywheel or an additional mass) C constant value E energy E A accumulator energy E F saw frame energy E PU power unit energy E T total energy EM electric motor F saw frame F C force caused by a counterweight F IA inertial accumulator force F IF inertial saw frame force F T total exciting force i transmission ratio IA inertial accumulator J moment of inertia m mass m 1 counterweight mass m A accumulator mass m F saw frame mass M P E amplitude value of the motor output torque n rotational speed of the cage of the planetary gear P power P A accumulator power P E electric power P F saw frame power P 0 power rating PCS power control system P CA charging power of the accumulator P D driving power P DA discharging power of the accumulator P M motor power P R recuperation power PG planetary gear r radius r 1 radius of the counterweight placing RG reduction gear R P amplitude value of the ground work reaction Dm S mass of extra saw blades which cause imbalance u angular displacement of the electric motor shaft _ u u angular speed of the cage of the planetary gear _ u u P 1 amplitude value of the angular speed of the driving motor shaft u 1 angular displacement of the electric motor shaft x 0 motor angular speed IntroductionIn frame sawing machines a saw frame cyclic motion produces an inertial force, which is the cause of many serious usage difficulties for these machine tools i...

• Material-saving and energy-saving belong to the basic requirements imposed on contemporary manufacturing processes. The realization of these processes gives measurable profi ts, not only economical but also ecological. In the case of wood sawing with circular saw blades, material-and energy-savings are dependent on total overall set of teeth (theoretical kerf) and teeth position accuracy in relation to

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The paper presents a mechatronic system for automatic inspection of circular saw teeth. The described system, based on numerical processing of recorded tooth images, has been implemented in the automatic vision controller system WKOPTar. The applied mechatronic system for the automatic spindle control positioning guarantees for the circular saw blade teeth a proper position enabling to grab and record tooth images even for non-uniform pitches in the examined circular saw blade. Some examples of measurements and geometry analyses of circular saw teeth were provided in order to illustrate the diagnostic usability of the apparatus. The system allows the user to determine up to 32 parameters for one tooth. However, the direct interpretation of physical parameter is sometimes partially limited by the software because the same parameter might have different meaning. Thus, in some cases a proper interpretation of the results may be feasible after recorded tooth screen analyses.