Improvements in and relating to ship's lifeboat launching apparatus

摘要

854,637. Davits. SCHAT, A. P. April 12, 1957 [April 19, 1956], No. 1190/56. Classes 113 and 115. An installation for suspending and launching a ships lifeboat 20 has davits each comprising a bracket 28 with a downwardly and outwardly sloping runway 28a, a davit arm 21 which is a substantially straight open structure adapted to be used as a ladder disposed substantially upright in the stowed position of the. boat and provided with a roller 25 intermediate its ends co-operating with the runway 28a to support and guide the arm, and a link 23 pivoted at one end 24 to the bracket and at the other 22 to the davit arm 21 at or near the lower end thereof so as to cause pivotal movement of the davit arm about the axis of the roller when the arm is moved downwardly by gravity on the runway. The boat is provided with an hoisting hook 29 engaged by an eye of a block 30 accommodating a sheave for the boat fall 31 one end of which is attached at 33 to the davit bracket and the other wound on the drum of a winch 32. The block 30 is suspended from a hook 35 at one end of a rope 35a the other end of which is secured to the shaft of the roller 25 so that as the fall 31 is paid out, the rope 35a pulls the roller outward. In the extreme outward position 211 of the davit arm, as shown at 351, 301, the hook automatically releases the block, whereupon the boat can be lowered under the control of a weighted lever 37 which has to be lifted to release the brake on the winch drum 32. Raising lever 37 releases a lever arm 38a secured on the shaft of a drum 38 rotatably mounted on the davit bracket, allowing the drum to rotate and loosen the lashing 39 wound thereon, and then slipping hook 38b to allow the boat to swing outboard. In Fig. 4 the outer lashings form a single rope 39a, the inner lashings 39b having at their free end a sheave 39c for the outer lashing so that when drum 38 tightens the lashings the central portion 39a will form a support for the boat cover. In its stowed position the boat is supported on a beam 42 secured to outwardly extending arms 43 of the davit arms 21.