Abstract: Procedure for retrieving an insertion of an underwater buoy (12, 50) in a well (11) at the bottom of a dynamically positioned vessel (10), at which a pulling line (16, 34) for interconnection with the buoy (12, 50) is lowered through the well (11) and hoisted to the deck (13) of the vessel (10), and the buoy (12, 50) is interconnected with the pulling line (16, 34) and hoisted into the well (11) by use of a winching device (15, 65) on the vessel, comprising the steps of attaching the pulling line (16, 34) to the connection unit (19, 32) on the deck (13) of the vessel (10), to lower the connection unit (19, 32) with the pulling line (16, 34) towards the buoy (12, 50) by use of a hoisting device (18, 30, 39) on the vessel (10) under possible guidance by use of the dynamic positioning system of the vessel, to place the connection unit (19, 32) on a cooperating device (20, 51, 52) on the top of the buoy (12, 50), whereby a terminal end on the pulling line (16, 34) is connected to the cooperating device (20, 51, 5

Abstract: Procedure for retrieving an insertion of an underwater buoy (12, 50) in a well (11) at the bottom of a dynamically positioned vessel (10), at which a pulling line (16, 34) for interconnection with the buoy (12, 50) is lowered through the well (11) and hoisted to the deck (13) of the vessel (10), and the buoy (12, 50) is interconnected with the pulling line (16, 34) and hoisted into the well (11) by use of a winching device (15, 65) on the vessel, comprising the steps of attaching the pulling line (16, 34) to the connection unit (19, 32) on the deck (13) of the vessel (10), to lower the connection unit (19, 32) with the pulling line (16, 34) towards the buoy (12, 50) by use of a hoisting device (18, 30, 39) on the vessel (10) under possible guidance by use of the dynamic positioning system of the vessel, to place the connection unit (19, 32) on a cooperating device (20, 51, 52) on the top of the buoy (12, 50), whereby a terminal end on the pulling line (16, 34) is connected to the cooperating device (20, 51, 5

Abstract: A trenching unit used to cut trenches in the seabed for laying pipelines or cables.

Abstract: An attachment (15) for a percussive rock drilling machine (12) for withdrawing a drill steel from a drilled hole. The drilling machine is of the kind which is displaceable along a feed beam (14) by a feeding motor. The attachment (15) comprises a spring housing (17) which contains a compressive spring (22) and a stopping member (23), the housing being suspended by flexible means (26, 27) from a yoke-shaped member (18) coupled on to the drilling machine body (19). The stopping member (23) is arranged to abut against a coupling sleeve (32) or the like on the drill steel (16). When retracting the drilling machine (12) by the feeding motorand starting the ordinary percussive action, the impacts directed downwards will be transformed to impacts directed upwards which loosen and withdraw the stuck drill steel (16) from the drilled hole.

Abstract: In an inverted siphon (4) in a sewer (1, 1a) where the approaching flow of sewage is insufficient for producing self-rinsing, a fluid reservoir (5) is arranged upstream of the inverted siphon which has sufficient volume for effecting rinsing, and the fluid content of the reservoir intermittently by means of driving members (6, 8, 9) is emptied through the inverted siphon at a velocity which corresponds to and at least during a certain time exceeds the required rinsing velocity.

Abstract: A ventilator is provided for the supply of untreated exterior air to a room. The ventilator has a valve seat (1), a valve body (2), means for connecting the ventilator to an exterior air duct (4) and operating means (6, 7) for resetting the position of the valve body. Stationary support elements (8) carry the valve body via a coupling (9) of the kind which, on repeated operating impulses from the operating means (6, 7) alternatingly takes the valve body to an outer position and returns it to an inner position. Both these positions are so selected that the inner one corresponds to the minimum demand for ventilation of an empty room while the outer one corresponds to the demand for ventillation with projected use by persons of the room.

Abstract: An air supply means includes a frame providing a valve seat and defining a valve opening. A valve body is adjustably connected to the frame. A plurality of V-shaped fasteners are used to secure the frame in an air duct. Each fastener has a pair of angularly disposed legs receivable in a slot in the opposed top and bottom walls of the frame, the legs meeting at an apex which is positioned toward the entrance to the duct. To attach the frame to the duct, a punch-like member is used to strike the apex of the fastener to spread the legs thereof and drive them through the slots in the opposing walls of the frame and thence, into the walls of the duct.