RAM-TYPE STEERING GEAR LEVER MECHANISM IMPROVEMENT PERSPECTIVES

Introduction. Any-type machine perfection depends on its ability to keep technical characteristic stability during all operation period. It acquires particular importance for steering gears, from which stability depends navigation safety. Purpose. The article purpose is the analysis of the ram-type steering gears lever mechanism improvement perspectives in the case of increasing structural completeness and decreasing details loading. Results. It is shown that ramtype steering gears evolution took place in the direction of reducing the number of redundant connections. Steering gear P-18 mechanism has q = 26 redundant connections, YOOWON-MITSUBISHI YDFT-335-2 steering gear mechanism – q = 20, HATLAPA R4ST-1000 steering gear mechanism – q = 16. Increasing steering gears lever mechanisms structural completeness took place through changing purpose, construction and than rejection of guide beam. In P-18 steering gear guide beam main purpose was unloading plunger (ram) fr om transverse force from tiller. Main influence on guide beam load capacity has size of gap between guide beam and ram support. In gap absence guide beam taking 92.3% of transverse force. When gap size is 0.25 mm, guide beam taking already 56.2% of transverse force, and when gap size increasing to 0.5 mm – only 20%. Other steering gear construction YOOWON-MITSUBISHI YDFT-335-2 save guide beam as element which makes rams rotation around its own axe impossible. The guide beam rigidity is enough to take only 7% of transverse force. HATLAPA R4ST-1000 steering gear has no guide beam that means that ram taking fully transverse force. It is shown that redundant connections number in four-rams steering gear can be reduced to q = 6, that means achievement by criteria of their minimization global parameters extreme. Conclusions. By criteria of structural completeness and ram loading by transverse force, using in all modern steering gears tangents-type lever-mechanism reached its development extreme. That's why increasing technical level perspective is in the area of using other type mechanism to transformation rams progressive motion to tiller turn.