US 3408973 A
Description (OCR text may contain errors)
1968 L. CURTIS ET Al. I 3,408,973
PEDESTAL AND PIVOT FOR SAILBOAT JIB Filed Sept. 11, 1967 2 Sheets-Sheet 1 INVENTORS Larry L. Curtis Thomas M. O'Gorman Big A. Cox
1 Attorney Nov. 5, 1968 CURTIS ET AL. 3,408,973
PEDESTAL AND PIVOT FOR SAILBOAT JIB Filed Sept. 11, 1967 2 Sheets-Sheet 2 IIIIIIIMIIIII h #Fig.3
INVENTORS Larry L. Curtis Thomas M O'Gorman Bing A. Cox
i Attorney United States Patent 3,408,973 PEDESTAL AND PIVOT FOR SAILBOAT JIB Larry L. Curtis, 303 Olive Ave., Larkspur, Calif. 94939;
Thomas M. OGorman, 21 Echo Ave., Corte Madera,
Calif. 94925; and Bing A. Cox, 7700 Palma Parkway, Sacramento, Calif. 95823 Filed Sept. 11, 1967, Ser. No. 666,742 4 Claims. (Cl. 114-98) ABSTRACT OF THE DISCLOSURE An improved item of sailboat hardware for mounting a jib boom which facilitates its installation, removal and operation. A novel combination of pedestal, horizontal and vertical pivots, anti-friction bearings and means of support which combine to give greatly improved results in sailboat operation.
Background of the invention A jib, sometimes referred to also as a club jib is a sail located forward of the mainsail and is sometimes referred to as a foresail. It increases the drive of the mainsail in normal cruising for various aerodynamic reasons known to those skilled in the art. It is essential that the boom of the jib be permitted to swing easily from port to starboard and also in a vertical plane depending on wind direction and velocity and relative direction of travel of the boat.
It is often required that the jib boom move in a horizontal and a vertical plane simultaneously with great ease. This must likewise be accomplished with a minimum of effort or attention from the crew. In the parlance of those skilled in the art the club jib should be self-tending.
Under racing conditions, as distinguished from cruising, the jib is often removed entirely and the mainsail adjusted accordingly.
The foregoing requirements therefore place great demands on the means used for mounting the forward end of the boom on to the boat. Existing devices do not provide the flexibility and ease of operation which are required. There is a tendency to stick or bind when the jib is subjected to sudden wind forces of varying magnitude and direction.
Summary of the invention It is therefore a principal object of our invention to provide a means of supporting the forward end of a sailboat jib which would give ease of operation of the boom in all directions under all sailing conditions.
It is another object of our invention to provide a means of supporting the forward end of a sailboat jib which would be readily removable and replaceable.
It is a more specific object of our invention to provide a pedestal equipped. with 'both horizontal and vertical pivots having a minimum of pivot friction and a means for securing a sailboat jib to said pedestal.
It is finally an object of our invention to provide a pedestal and pivot support for a sailboat jib which would be more flexible, operate more easily and be superior to all existing means of support now in use.
We have discovered that by making a novel and unusual combination of a pedestal with a vertical pin, swivel block and horizontal pivots, equipping the rotating parts with anti-friction bearings and providing flexible means for connecting the horizontal pivots to the jib boom We are able to overcome the objections to existing devices and obtain unusual and unexpected improvements in operation.
3,408,973 Patented Nov. 5, 1968 Description 0 the invention Description of the preferred embodiments Referring now to FIG. 1 there is seen the bow portion of a sailboat hull 1 which carries the forward deck 2. The jib 3 is carried by boom 4 and the mainmast is shown at 5. The traveler serving the jib boom comprises traveler rail 6 and runner carriage 7. The runner 7' is connected to the boom 4 by means of block and tackle comprising boom vang 8 which leads to sheet line 9 over sheaves 10.
The improved pedestal and pivot which comprises our subject invention is shown at 11 and the winch for adjusting or sheeting the jib is shown at 12.
Referring now more particularly to FIGS. 2 and 3, there is seen the foot or horizontal base member of our pedestal 21 equipped with countersunk holes 22 for fastening base member 21 to the top of deck 2. The pivot pin of our invention comprises a screw portion 23 and a journal portion 25. Nut 24 serves to secure the pivot pin to the deck 2 by fastening on screw portion 23 as shown. The journal section 23 is equipped with a vertical bearing member 26. Swivel block 31 is rotatably mounted on journal section 25 through bearing 26 described above. A thrust bearing 27 which is preferably of the ball type serves to carry swivel block 31 on to base member 21.
Positioned on opposite sides of swivel block 31 are arm pivots 30 which serve to hold side arms 32 and permit them to rotate in a vertical plane. The side arms 32 in turn serve to hold the forward end of jib boom 4 and screw holes 33 are provided for this purpose. Rotation between side arms 32 and pivots 30 is facilitated by bearings 34 which is held in position on the pivot by cap screw 35. The entire assembly is held in position by acron nut 29 acting on screw 28 which forms a part of our pivot pin.
Bearings 26 and 34 are of the anti-friction type and we have discovered that needle bearings serve our purpose best. These may be conventional hard steel bearings as are available commercially or when desired, we may employ stainless steel bearings for this purpose.
It should now be evident to those skilled in the art that while we have disclosed a rugged as well as flexible construction for our device, it is readily removable when it is desired to eliminate the jib as discussed above. This is easily accomplished by merely loosening nut 24 on threaded section 23 and lifting all but base member 21 off of deck 2. The hole in the center of base plate 21 may be plugged up to prevent shipping in of water by means of any suitable plug. We have found that a neoprene plug is most suitable for this purpose. The jib may then be stowed away and the boat operated without it. When it is desired to use the jib again the plug is removed and the steps described above are repeated in reverse order.
The pivots 30 must, of course, be in axial alignment and we have discovered that unusual and unexpected results in the way of ease of motion of the jib boom are obtained when the axis of these intersect the vertical bearing 26 through its horizontal center of gravity or centroid or slightly below it. With this arrangement we have discovered that a condition of dynamic equilibrium is at tained and that motion of boom 4 in a vertical or in a horizontal plane or simultaneously in both is obtained with very great ease regardless of wind pressures, direction of travel of the boat or relative position of jib 3.
3 e While we have described a preferred embodiment of our invention, we do not limit ourselves to the disclosure made herein except as we do so in the claims which follow.
' 1. A device for operating the jib boom of a sailboat comprising:
a horizontal base member;
means for fastening said base member to the deck of said boat;
a vertical pin member passing through said base member and said deck;
means for fastening said pin member to said deck;
a swivel block rotatably mounted on said pin member;
a vertical thrust bearing interposed between said swivel block and said base member;
a pair of horizontal pins positioned on opposite sides of said swivel block in axial alignment with each other;
a pair of parallel plates rotatably mounted on said horizontal pins;
4 means for fastening said plates to boom.
2. The device of claim 1 in which the axis of said horizontal pins intersects said swivel block at a point slightly below its centroid.
3. The device of claim 1 in which said swivel block is rotatably mounted on said pin member and said parallel plates are rotatably mounted on said horizontal pins respectively by means of anti-friction bearings.
4. The device of claim 3 in which said anti-friction bearings comprise needle bearings.
References Cited UNITED STATES PATENTS 3,310,017 3/1967 Dyer 1l498 MILTON BUCHLER, Primary Examiner.
2 T. M. BLIX, Assistant Examiner.
one end of said jib