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Rotary mowers are often used for forage harvesting in agriculture, as this technology can achieve a high throughput. These knives are therefore exposed to high levels of wear and tear, and will also be often changed because of loss of material by bad cutting quality. That is why it is interesting to save costs during manufacturing in spite of a correspondingly long service life. This research records the current manufacturing quality of the mower blades and examines how they behave in comparison. Based on the obtained results, further decisions on the methods, procedures and ways of extending the life of the disc mower blades should be proposed. For the investigations, a test bench based on a wear pot was used. The wear that occurs on the blade is determined using several parameters and compared accordingly. The parameters of the test setup determined as a result of the test can be used for further studies of wear resistance.

The proposed study is focused on the development of a novel modification of the slider-crank mechanism, the kinematic scheme of which is organized by coupling planar and spatial (screw) kinematic chains. The structure of this mechanism provides the end-effector with a cyclic movement along a helicoidal trajectory, while all other links have planar motions. A kinematic analysis of the synthesized mechanism is discussed in this study. The motion variables of the end-effector at different pitches in the screw joints are determined analytically and numerically. Based on the mechanism’s kinematic scheme, its assembling computer-aided design (CAD) model has been created, in accordance with which a physical prototype has been built. A functional performance of the prototype is studied by comparing the displacements of its end-effector with analogical displacements of the CAD model. The question of the technological application of the developed mechanism for spring winding and various objects’ screwing has been considered in this study.

Für die Messung der Biege- und Schnitteigenschaften halmartiger Güter wurde ein Universalprüfstand entworfen. Die mit ihm ermittelten Messwerte dienen der Erstellung von Simulationsmodellen zur Abbildung landtechnischer Schnittprozesse. In der vorliegenden Studie werden Weizenhalme untersucht. Die Schnittversuche erfolgen mit zwei Geschwindigkeiten und zwei Schnittwinkeln. Die Mittelwerte aus jeweils 50 Messungen werden miteinander verglichen. Der Feuchtigkeitsgehalt der Proben liegt zwischen 5,5 und 7,1 %. Die Biegespannungen betragen für das erste Internodium 1,09 N/mm², für das zweite 0,99 N/mm² und für das dritte 1,07 N/mm². Bei den Schnittversuchen tritt die höchste Spannung (4,44 N/mm²) beim Schneiden des zweiten Internodiums auf (50 mm/s, 40°). Die niedrigste Spannung (2,20 N/mm²) tritt beim Schneiden des dritten Internodiums auf (150 mm/s, 60°). Bis auf eine Ausnahme ist die auf den Probenquerschnitt bezogene Schnittenergie (12,18–19,85 mJ/mm²) bei der Auswahl des größeren Winkels höher. Die mittleren Variationskoeffizienten liegen zwischen 5 und 32 %.