ARTICULATED OAR Russian patent published in 2006 - IPC B63H16/10 

FIELD: boatbuilding; construction of oars for rowing with face forward.

SUBSTANCE: proposed articulated oar has handle with semi-gear, rod with semi-gear and ears made on its other end with vertical coaxial axles, lever with vertical bracket secured to it from below, rod articulated with lever ears on one side and with axle on swivel plate on other side; swivel plate is secured on rowlock which is secured on brackets of shallow-draft vessel or on its side. Bracket is secured to lever from below; streamlined bracket is tubular in shape and is provided with rectangular horizontal section. Two coaxial holes are provided in lower front corner of wide sides of this section. These holes receive blade which is rotatable relative to horizontal axis; this blade has longitudinal ridge on its concave side which strengthens the blade by 1/3 of its width. Between ridge and longitudinal tips of blade there are two trough-shaped streamlined chutes of double curvature. Flat is provided along axis of symmetry lengthwise relative to blade where bracket-ear having two horizontal coaxial holes of larger and smaller diameters is secured. Hole of larger diameter is used for securing the blade and holes of lesser diameter are used for securing the spring-loaded rod provided with bead and shoulder from below. Compression spring is fitted on rod and is supported by lower face of lever. Upper end of rod is brought to lever top through hole made along axis of symmetry of lever; it is provided with bearing roller horizontally revolving on cantilever pin. Horizontal plate is secured on upper ear of rod at point where lever is articulated to rod. This horizontal plate is secured by means of dowel pins and screws. At other end plate is secured on opposite side to sector of L-shaped section at angle of 80-90° or to sectional sector for control of stroke angle; "hill" which is spring-loaded downward is secured to one end of sector ; on other side vertical wall of sector is tangentially bent away inside sector angle by 10-15°.

EFFECT: increased rate of rowing; enhanced efficiency at use of man power.

9 dwg