37results about "Bilge keels" patented technology

The invention relates to a fin stabilization system adapted to minimize roll about the longitudinal axis of the boat during sharp cornering at very high speeds. In one form, equipment such as a machine gun is mounted to the bow of the boat and targets are adapted to be engaged in high-speed maneuvers when cornering and the deck of the boat is not excessively rolled whereby blocking visibility in a turn.

The invention relates to a bilge keel. A body structure of the bilge keel comprises a fixed clamshell structure (2) and a rotary clamshell structure (1) which are in a flat shape after being combined; the head and tail ends are in a streamline shape; the fixed clamshell structure (2) is fixedly connected to a bilge strake (3); the rotary clamshell structure (1) is connected with the fixed clamshell structure (2) through a rotary shaft system; the rotary shaft system is used for opening and closing the rotary clamshell structure (1). The bilge keel can increase the rolling damping of a ship, effectively reduce rolling of the ship and enhance the rolling stability.

The invention relates to the field of designing displacement vessels with an air cavity on the bottom. A displacement vessel has a recess in the bottom for the formation of a single air cavity with a wave-like profile, the recess beginning at a step in the bow and being delimited by skegs along the sides and a stern arch in the form of an inclined plate. The cavity of the recess is connected to a pressurized air supply; inside the recess there are longitudinal keels to restrict the transverse movement of the air, and transverse baffles in the form of inclined plates are arranged one after the other in a streamwise direction such that they can be deployed into a working position and folded back adjacent to the bottom. Downstream of the step in the bow which forms the recess, a plate is mounted such that it can pivot by means of the lowering or raising of the leading edge thereof about a spindle that is transverse to the bottom, said spindle being connected to the plate and being fastened to the surface of the bottom recess. The streamwise length of the plate is such that as the plate pivots about the spindle it joins the surface of the bottom upstream of the step with the surface of the bottom inside the recess in order to prevent flow separation downstream of the step. The plate is capable of limiting the lowering of its leading edge to the level of the bottom of the ship in the region of the step. The invention provides a ship with improved performance characteristics.

The invention relates to the field of ships, and particularly discloses a ship bottom structure and a fatigue life computing method thereof. The ship bottom structure comprises an inner bottom longitudinal bone, an outer bottom longitudinal bone, a reinforcing rib and a rib plate, wherein the outer bottom longitudinal bone is parallel to the inner bottom longitudinal bone, the reinforcing rib is connected with the inner bottom longitudinal bone and the outer bottom longitudinal bone, and the rib plate is connected to one side of the reinforcing rib; and the two ends, in the height direction, of the rib plate are connected to the inner bottom longitudinal bone and the outer bottom longitudinal bone correspondingly, and the rib plate is a flat plate. According to the ship bottom structure, the rib plate is the flat plate, compared with a rib plate structure in the prior art, the rib plate in the ship bottom structure does not need to be provided with a toggle plate, the rigid requirement for the inner bottom longitudinal bone and the outer bottom longitudinal bone of the ship bottom structure can be met by adopting the rib plate, the weight of the structure is lowered, the structural form is simplified, the welding workload is reduced greatly, the construction efficiency is improved, and meanwhile, due to the fact that the toggle plate does not need to be arranged, the weight of a ship is lowered, and the production cost of the ship bottom structure is further saved.

A twisted rudder blade for a ship having a twist that is adapted to the configuration of the flow of the water in the region of the rudder blade if no propeller in operation is disposed in front of the rudder blades in the direction of travel of the ship.

A motion reduction apparatus has an orthorhombic shaped floating main body (11), a plumb plate supported vertically on one side section of the floating main body by stay members (13), and flow sections (15) for flooding with incoming water are provided between the floating main body and the plumb plate in such a way that an upper end section of the plumb plate is at about the same height as the bottom surface of the floating main body.

The invention relates to a control method of a frog mouth type bilge keel. A main structure of the frog mouth type bilge keel comprises a fixed clamshell structure (2) and a rotary clamshell structure (1). The rotary clamshell structure (1) is connected with the fixed clamshell structure (2) through a rotary shaft system. The control method of the frog mouth type bilge keel includes the steps that when a ship sails, the rolling angle, the angular speed and the angular accelerated speed of the ship are monitored, ship draught information is obtained, and the ship stability change is checked; if any index of the three parameters including the rolling angle, the angular speed and the angular accelerated speed continuously exceeds the upper limit of a corresponding safety threshold value within a set time, a motor is used for driving the rotary shaft system to unfold the rotary clamshell structure of the bilge keel; and if the three parameters including the rolling angle, the angular speed and the angular accelerated speed are continuously lower than the lower limit of the corresponding safety threshold value within the set time, the motor is used for driving the rotary shaft system to fold the rotary clamshell structure of the bilge keel. By the adoption of the control method of the frog mouth type bilge keel, the bilge keel can be intelligently controlled to be unfolded and folded; and the rolling damping of the ship can be increased, rolling of the ship is effectively reduced, and rolling stability is enhanced.

The disclosure relates to a fin stabilization system adapted to minimize roll about the longitudinal axis of the boat during sharp cornering at very high speeds. In one form, equipment such as a machine gun is mounted to the bow of the boat and targets are adapted to be engaged in high-speed maneuvers when cornering and the deck of the boat is not excessively rolled whereby blocking visibility in a turn.

A watercraft (99) having a stepped hull (100) including a forward hull portion (103), a first stepped hull portion (106), and optionally a second stepped hull portion (108). Outboard ram air fins (120) extend outwardly from the hull and downwardly along the stepped hull portions. Outboard strakes (110, 112) are fixed to the stepped hull portions, and may be tapered to define ports thereto. During planing operation the channels defined by the fins compress the incoming air which is thereby at least partially forced under the stepped hull portion. In level operation the flow through the channels tends to keep the stepped hull portions in good contact with the water.

A flow control mechanism, for improving pressure resistance and hull vibration, includes a lower fin and an upper fin. The lower fin is disposed between a second station and a fourth station in a length direction of a ship and between 10% and 20% of a design draft from a bottom of the ship in a height direction of the ship, the lower fin being inclined at an angle of 20 to 40 degrees with respect to a design draught (or base) line. The upper fin is disposed between the second station and the fourth station in the length direction of the ship and between 30% and 60% of the design draft from the bottom of the ship in the height direction of the ship, the upper fin being inclined at an angle of 10 to 30 degrees with respect to the design draught (or base) line. Further, an additional fin is disposed between a first station and a third station in the length direction of the ship and between 5% and 20% of the design draft from the bottom of the ship in the height direction of the ship, the additional fin being inclined at an angle of 10 to 40 degrees with respect to the design draught (or base) line.

The invention relates to a sliding rail boat structure.The sliding rail boat structure comprises a boat.A jet-pump protection frame and a self-centering device are installed at the tail of the boat, a driving control table is located in the middle of the boat, an inclinable lamp bracket is installed on the driving control table, and a driver seats behind the driving control table; a plurality of passenger seats are located at the front portion of the boat; a main engine is installed at the portion, located below the driving control table, inside the boat located, a main output shaft of the main engine is connected with a jet pump, and an oil box is arranged at the portion, located below the passenger seats, inside the boat; a boat hook is installed at the head of the boat; fenders are arranged on the outer ring of the upper surface of the boat, and hand guards are arranged on the fenders at intervals.The structure of the boat is changed, the service life of the boat is prolonged, and the use reliability of the whole machine is improved.