Article deals with the field of machinery, namely with the protecting of devices for mechanical driving systems. New construction of safety-overrunning clutch, operating on gearing principle, where safety and overrunning parts are mutually integrated, has been proposed and studied in the article. It has practical importance for building, based on modular principles, machines. As the result of the theoretic studies, the expressions to calculate the following specific clutch torques have been obtained: rating torque, torques of beginning and ending of operation. On the basis of the mentioned studies, the expressions to estimate the clutch main operation characteristics have been obtained -nominal torque exceeding coefficient, accuracy and sensitivity coefficients. These expressions are practically important for proposed clutch calculations. The analysis performed demonstrates that in order to increase the clutch load capacity, the grooves must be made with less inclination angles to clutch axis. Obtained results indicate the advisability of installing the clutch on low-speed shafts. It is shown that the clutch overload sensitivity could be increased by the reduction of the spring rigidity. The calculations performed also demonstrate that balls diameter reduction has a positive effect on the clutch operation parameters. Obtained expressions and numerical results are practically important for proposed clutch calculations. It is shown that in terms of the accuracy of operation, the studied coupling fully corresponds to the level of common and investigated designs of safety clutches.

The structure of steering gear’s HATLAPA mechanism is analyzed. It is shown that presence of redundant constraints in it increases laboriousness of gear montage and respectively worsen maintainability. On the basis of provided analysis developed mechanism with reduced more than twice redundant constrainsts number.

he article deals with steering gears, used on marine and river ships, namely with ram-type steering gears. Article topicality due to the fact that ship controllability and sailing safety depends of steering gears reliability. Reliability could be increased through the refinement of processes, which took place during the perception and transfer of load. Process of lateral force perception by plungers and guide beams is studied theoretically. It is shown that perception depends of gap size between plunger and sleeve and could pass in one, two or three stages. Those stages are characterized changing in the loading process plungers fixing conditions, and respectively plunger lateral load proposed to determinate by three design schemes. Received expressions for calculation ultimate gaps of «plunger-sleeve» pare landing, that gives the limits of application each of three design schemes. Ratios for determination load of plunger and guide beam are received trough consideration their joint deformation for each design schemes. On the example of YOOWON-MITSUBISHI YDFT-335-2 ram-type steering gear is shown that in new gear, where landing gap is minimal and conditioned by tolerances of plunger and sleeve diameters, guide beam can take only 2.0…6.5% of lateral force, which applied to it and plunger from tiller. In steering gear with partially worn out plunger and sleeve in time of rudder feather shifting from diametric plane to board (when α = 5…35º), guide beam could take 4.7…6.8% of lateral force. The source of origin significant loads on plungers in ram-type steering gears is application of sinus-type mechanism for transformation progressive plunger motion to rotating tiller motion. Decreasing lateral loads on plunger through using unloading guide beams, with considering low unloading percent is ineffective. Guide beams availability complicates steering gear construction, increasing number of friction surfaces and trough this complicates steering gear maintenance.

Article deals with safety-overrunning clutches for mechanical transmissions. Modern design of safetyoverrunning clutch with grooves sides inclined to semi-coupling radius has been described and researched in the article. It has practical value for creation modular-type machines. On the basis of the theoretic studies, the expressions for obtaining the main specific operation parameters have been proposed: rating torque, beginning and ending operation torques. As the result of the studies, the equations for estimation the clutch main operation characteristics have been received -rating torque exceeding coefficient, coefficients of clutch accuracy and sensitivity. On account of modeling and comparison with clutch where grooves sides are parallel to the radius made a number of important conclusions. The analysis performed demonstrates that clutches with inclined to radius grooves sides in general have higher operation characteristics compared with clutches with parallel to radius grooves sides, particularly higher accuracy coefficient and lower rating torque exceeding coefficient. Obtained results make it possible to recommend for highly loaded large-mass systems clutches with low values of grooves to clutch axe and grooves sides to radius inclination angles, because it provides balls contact with plane sides grooves surfaces and through this allows to decrease contact stresses compared with clutches with grooves sides parallel to radius; allows to provide high load capacity with low rating torque exceeding in overload mode; in clutches with inclined to radius grooves sides friction impact manifests less in operation with high rotation frequency.

The structure of the MAK M43 diesel high pressure fuel pump driving is analyzed. It is shown that presence of redundant constraints in its mechanism is the reason of roller bearings failure. It is proposed redundant constraints elimination by adding movabilities in mechanism.