GB560914A - Improvements in and relating to ship's rudders - Google Patents

Abstract

560,914. Ships' rudders; welding metal articles. LIVINGSTON, J. Oct. 21, 1942, No. 14780. Convention date, Sept. 27, 1941. [Class 114] [Also in Group XXII] A rudder of the kind mounted about a vertical axis A, A in the stream from a propeller 5 and formed with an intermediate horizontal plane 5-5 in line with the propeller axis and steering surfaces fore and aft of the vertical axis, is constructed with the forwardly extending steering surfaces 6 meeting to form a leading edge 8 directed downwardly and outwardly to one side of the vertical longitudinal median plane of the rudder, and the similar surfaces 11 below the said horizontal plane form an edge 13 directed upwardly and outwardly 'to the other side of the median plane, and a web 16 connects the oppositely directed parts at the forward end, and a similar web 7, Fig. 6, connects the other parts at the rear end. The rudder is preferably of the balanced type. In constructing the rudder the stock is made from a tube 30, Fig. 4, slightly shorter than the height of the rudder, and castings 31, 36 fitted with pintles 32, 37 for mounting the tube are welded thereon. A series of shaped diaphragm plates 40a ... 40g and 41a ... 41g are welded to the tube, and also a bottom plate 42, top plate 43, and a shelf 44 of heavier stock than the diaphragm plates are also welded to the tube 30. The side plates 20, 21 are welded to the diaphragm plates while held temporarily secured thereto by wedges 55, Fig. 6, which engage pins 53 on tongues 50 secured to the diaphragm plates and passed through slits in the plates 20, 21. The tongues 50 are cut off after the welding is completed. The plates 20, 21 are welded to the tube 30 and to pipes 48 shaped to give the required contour to the leading edge of the rudder of the plates 20, 21 are formed of two parts as indicated on Fig. 6, the ends are welded together as shown at 30a. The trailing edges of the plates 20, 21 are welded together along the lines 22, 27, Fig. 1. In a modification, Fig. 8, rudder is mounted differently, the rudder stock 70 corresponding to the tube 30 being extended through a neck bearing 73 secured to the transom frame, and provided with a bearing sleeve 83 of lignum vitµ in which is mounted a brass bushing 81 which is shrunk on to the tube 70. The tube 70 is keyed and bolted to a stock extension 79. Specification 560,922 is referred to.