Abstract: The invention relates to a device for extracting energy from waves and having a pump arranged to be operated by relative motion between members of the device in response to waves. The pump according to the invention has a pump body with a flexible portion extending between the members so as to define a pump chamber having a volume which varies as a result of the aforesaid relative motion. In one form of the invention the pump body is provided by a tubular bellows comprising elastomeric material. A plurality of such pumps may be disposed between the members, each pump being activated by said relative motion.

Abstract: The invention relates to a device for extracting energy from waves, the device having a pump or a number of pumps arranged to be operated by relative motion between hingedly connected members of the device in response to waves so as to displace a fluid. The device according to the invention is provided with a vane pump having a pump chamber defined by one of the members and a vane extending from an adjacent member so as to be displaced in the pump chamber by the relative motion of the members to displace the fluid. The members may be hingedly connected together at a number of locations at which a respective bearing is supported by a resiliently flexible mounting.

Abstract: A crane having a hoist winch with a hoist cable connected to a link which parts at a predetermined tension, and a jib over which the hoist cable is reeved for connection to a load. A derricking system on the crane includes a derricking winch and a derricking cable for luffing the jib. It also includes an hydraulic ram connected to one or more preloaded hydropneumatic accumulators in which the gas pressure is set to cause the ram to react against a predetermined overload. The hoist winch is released by mechanism responsive to movement of the ram, due to exceeding said predetermined overload, so that the hoist winch, when released, pays out the hoist cable to enable parting of the link.