Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
  • B63B41/00—Drop keels, e.g. centre boards or side boards ; Collapsible keels, or the like, e.g. telescopically; Longitudinally split hinged keels
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
  • B63B41/00—Drop keels, e.g. centre boards or side boards ; Collapsible keels, or the like, e.g. telescopically; Longitudinally split hinged keels
  • B63B2041/003—Collapsible keels, or the like, e.g. telescopically; Longitudinally split hinged keels
  • B63B2041/006—Telescopically collapsible keels

Definitions

• the invention relates to an arrangement of the type specified in the preamble of claim 1.
• Sailboat with its longitudinal axis forms an acute angle. Due to this angle of attack or drift of the entire boat to the direction of the course, the underwater ship alone or with special attachments, such as keel and sword, generates a windward force that counteracts the drift. However, this adversely affects the flow of water around the boat, so that drag increases.
• the keel surfaces In the case of hulls with a shallow draft, the keel surfaces (sword surfaces) must be made relatively large and deep in order to generate the necessary upward windward lift even in the lower speed ranges. At higher speeds, the area can only be reduced in sword boats by lifting the sword and thus the induced drag can be reduced. If the yacht has a fixed keel, the resulting buoyancy is limited by the largest possible angle of attack of the entire boat, since the increase in this angle increases the boat's induced drag disproportionately. The induced drag increases at 14 ° drift angle by 14% of the pure form drag 4 ° by 34%, at 8 ° by 8o% and at 1o ° by 106%. The smallest angle of attack which still generates sufficient buoyancy is approximately 4 °.
• the force generated by the keel or sword has an additional heeling, since it complements the heeling force of the sail.
• the wind power component causing the drift is now completely or partially compensated for by the lateral buoyancy components generated by the fin keel or the sword, so that the drift is reduced.
• the effect between the course and the longitudinal axis of the ship is reduced to 0 °. As a result, the boat body's drag decreases.
• the rear part of the body serving as a fin keel or sword consists of a trim flap which is attached to the front part of the body by a hinge and can be pivoted to port or starboard.
• a trim tab has the disadvantage that the horizontal longitudinal section profile of the body serving as a fin keel or sword is strongly arched in the rear third when the trim tab is swung out. However, this is unfavorable for the buoyancy and increases the resistance.
• the invention is based on the object of creating an arrangement of the type specified in the preamble of claim 1, which is characterized in that it generates a larger buoyancy force due to the asymmetrical profile in a relatively small area. It has an angle of attack without the entire boat being brought up to the course.
• the buoyancy and the angle of attack are adjustable.
• FIG. 1 is a side view of the hull of a sailing boat with a two-part fin keel of the embodiment explained above,
• Fig. 2 shows the floor plan belonging to Fig. 1, partly in section along the line 2-2 of the Fig. 1 ,
• FIG. 4 shows a representation corresponding to FIG. 3 of a modified embodiment
• Fig. 5 shows the longitudinal section 5-5 through the
• Fig. 7 shows a cross section through that shown in Fig.5
• the boat body 10 of a sailboat shown in FIGS. 1 and 2 is provided with a two-part body 12 serving as a fin keel, which consists of two parts 14 and 16 arranged one behind the other in the direction of travel.
• the front part 14 is designed symmetrically to the vertical longitudinal median plane 18 of the hull and has a drop-shaped neutral cross-sectional profile in each of the cross-sectional plane 2-2 of the figure. 1 parallel plane, advantageously tapered downwards.
• the rear part 16 of the body 12 forming the fin keel is arranged on the leeside of the central plane 18, has an approximately triangular cross-sectional profile and approaches the front fin keel part 14 with its front side 20, so that it forms its teardrop-shaped profile asymmetrical see buoyancy profile added. During the journey, this two-part fin keel therefore exerts a wind-up component, indicated by the arrow 22, on the boat body 10 in the windward direction.
• the part 16 of the fin keel tapers downward in a favorable embodiment. It is set in the embodiment shown in FIGS. 1 and 2 while driving so that its lower end is flush with the lower end of part 14.
• the sailboat would take course 24 under the influence of the component of the wind power acting transversely to its longitudinal axis with an angle of attack of 4 °. Part 16 creates the necessary angle of attack of the profile, so that the buoyancy is also generated when the course of the boat coincides with the longitudinal axis of the ship.
• the rear part 16 of the body 12 serving as a fin keel is formed by two halves 16 and 26 which can be raised like a sword, see FIG. 3, of which only the leeward half is lowered, while the other is lowered into a sword case 28, FIG 6, is pulled up.
• the lower half - designated 16 in FIGS. 1 and 2 pull up and lower the other half 26.
• the two halves 16 and 26 of the rear part of the fin keel are slidably guided and provided with appropriate drives.
• the sword case 29 can also accommodate the front part 14 'of the fin keel, so that it does not rigidly attach to the hull, as in the embodiment of FIG. 6, but in Sword box 29 is slidably guided. You can therefore lower the fin keel more or less as required and pull it all the way up when driving upwind.
• the sword case 29 thus slidably receives the front part 14 and the two halves 16 and 26 of the rear part of the fin keel.
• cable pulls are used to drive these individual parts.
• a rope pulley 32 is mounted, over which a rope 34 runs, which runs through the sword box . , extends upwards and runs at the upper end over deflection rollers 36 to drivable rope rollers. If the front part 14 of the fin keel is raised from the lowered position shown in FIG. 5 by pulling the rope 34 tight, then its foot 30 takes the respectively lowered half of the rear part - this is the case in FIG. 5 ⁇ showed location half 26, up with.
• a pull cable 38 is fastened to each half 16 and 26 of the rear part of the raft keel, with the aid of which each of the two halves 16, 26 can be pulled up or lowered by itself.
• FIG. 4 shows an embodiment of the fin keel, in which there is a flow-through gap between the two halves 16 and 26 of the rear part of the body 12. finds. Accordingly, the mutually facing corners of the triangular cross-sectional profile of the halves 16 and 26 are rounded. The cross-sectional profile of each of the two halves 16 and 26 can also be made neutral.
• the dimensions of the body 12 can be dimensioned smaller than an undivided fin keel for a boat body 10 of a given size, because its effect is enhanced by the force component 22 generated by it. For this reason, the point of application is Kraft ⁇ component 22 also close to the ship's hull, which the pre- • provides in part that the force 22 seeks to heeling to a lesser extent by Lee the hull lo.
• Fig. 7 illustrates a cross section through the in
• Fig. 5 shown fin keel and by the sword box to illustrate the cable drives for the halves 16 and 26 of the rear part of the fin keel.
• Rope sheaves 40 over which the ropes 38 run, are mounted at the bottom of the sword case. These ropes are guided over upper sheaves 42 which can be driven in one direction or the other. The ropes engage halves 16 and 26 at the top.
• the ropes run through holes 44 which are arranged in the outer walls of the slideways in which the halves 16 and 26 are slidably guided.
• the outside of the sword case is covered by walls 46.
• the two downwardly tapering halves 16 and 26 have shoulders 48 on the outside, which can rest against the bottom of the hull 10 on both sides of the slot provided at the bottom of the sword case, in order to limit the downward stroke of the halves 16 and 26.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• Ocean & Marine Engineering (AREA)
• Toys (AREA)
• Other Liquid Machine Or Engine Such As Wave Power Use (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6092095

Family Applications (1)

Country Status (4)

Cited By (1)

Families Citing this family (6)

Citations (6)

• 1980
  • 1980-01-15 DE DE19803001279 patent/DE3001279A1/de not_active Withdrawn
  • 1980-12-17 WO PCT/DE1980/000189 patent/WO1981001990A1/de unknown
  • 1980-12-17 EP EP80108000A patent/EP0032223A1/de not_active Withdrawn
• 1981
  • 1981-09-14 DK DK408881A patent/DK408881A/da not_active Application Discontinuation

Patent Citations (6)

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