US2879736A

US2879736A - Boom end fitting for sailboats

Info

Publication number: US2879736A
Application number: US543978A
Authority: US
Inventors: Smallpeice Cosby Dona Philipps
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-06-10
Filing date: 1955-10-31
Publication date: 1959-03-31
Anticipated expiration: 1976-03-31

Description

March 31, 1959 c. D. P. SMALLPEICE BOOM END FITTING FOR SAI-LBOA'TS 2 Sheets-Sheet 1 Filed Oct. 31, 1955 FIG.2.

C D. P, 5MALLPf/(F March 31, 1959 c. P. SMALLPEICE 2,879,736

BOOM END FITTING FOR SAILBOATS Filed Oct. 31, 1955 2 Sheets-Sheet 2 FIGB.

C. 1). R 5 MALI. PE/CE 2,879,736 BOOM END FITTING FOR SAILBOATS Cosby Donald Philipps Smallpeice,

Riddells Bay, Bermuda The invention relates to a boom end fitting such as is used in sailing boats, for example, for spinnaker sails where it is desirable that the fitting for attaching one end of the boom to the mast shall be the same as that on the other end of the boom for attaching the sail to the latter.

According to the invention the fitting includes one element of a spherical type joint, for releasable engagement with a coacting element fast with the mast, and a means for attaching the sail to the boom, the joint and the sail-attachment means being operable to their releasing positions by the action of a single latch, or of a latch and withdrawa-ble plunger respectively.

Preferably the joint element of the fitting is a cup, associated with a latch arrangement, for releasable engagement with a coacting ball fast with the mast, and the sail-attachment means includes a withdrawable plunger to bridge a gap between a pair of jaws for holding an eye fast with the sail.

Preferably, also, the latch arrangement of the fitting is biassed into its engaging position, and also acts on the associated plunger for the bias to urge the said plunger into its bridging position.

In the case where there is one of the fittings at each end of a boom, each latch arrangement can be connected to be acted upon by 'a single, manual control which simultaneously operates the latch arrangement to its disengaging position and the associated plunger to its nonbridging position (although, of course, there may only be a need to operate the latch arrangement at one end of the boom to disengaged position, and the plunger at the other end of the boom to its non-bridging position).

In the accompanying drawings:

Figure 1 is a diagrammatic plan view of a yacht hull showing the bottom edge of a spinnaker sail, set with the boom extending over the port side;

Figure 2 is an elevation, partly in section and with a central portion broken away, of a spinnaker boom according to the invention, and a fragment of an associated mast; and

Figure 3 is a section on line 3-3 of Figure 2.

Referring to Figure 1, the spinnaker boom 11 has

identical end fittings

12a, 12b of which the inboard one (i.e., 12a in the example shown) is supported from the mast 13 and the outboard one is attached to the port bottom corner of the sail 14, the bottom corners being sheeted at 15, 15 to the hull 16 of the yacht. When it is desired to gybe, the end 12a of the boom is detached from the mast and connected to the starboard bottom corner of the sail, while the end 12b of the boom is detached from the port bottom corner of the sail and connected to the mast.

The

end fittings

12a and 12b are identical and, in the construction shown in Figure 2, each includes a tapered socket l7 fitting over a correspondingly tapered end of the main portion 11 of the boom and suitably secured in position thereon. Integral with each socket 17 is an 2,879,736 Patented Mar. 31, 1959 ice inverted spherical type ,or cup-like portion 18 which is to fit over a ball 19 fast with a bracket 20 secured at 21, 21 to the mast 13. Adjacent the cup portion 18 is a substantially Y-shaped latch-plate 22 which has its central limb pivoted at 23 in a housingformed by a transverse slot 24 in the region between the socket 17 and the portion 18. This latch-plate has a forked upper end between the limbs 22a of which extends a plunger 25 which is guided at one end by a screw plug 27 engaged in a bore of the fitting, and a spring 28 reacts between the plug 27 and an abutment 29 on the plunger 25. U This abutment bears on the latch-plate for urging a nose 30 of the latter into a position to obstruct the withdrawal of the cup 18 from the ball 19, but not, in the particular construction shown, to contact the ball 19.

Fast at the back of the cup 18 is a pair of jaws 31, 31a having aligned holes through which the plunger 25 extends to form a bridge for confining an eye 32 fast with the sail. As shown at 25a, the outer end of the plunger 25 is of reduced diameter, and the hole in the jaw 31a is of corresponding size, whereby that jaw coacts with the step thus formed on the plunger for limiting outward movement of the latter under the influence of the spring 28.

Conveniently the limbs 22a of each latch-plate are united by a pin 33 to which is secured a lanyard 34 passing through a hole in a bracket 35 fast with the socket 17. In this way a pull on the lanyard 34 will turn the nose 30 of the latch-plate 22 about a pivot 23 through approximately 20, thus allowing socket 18 to be moved clear of the ball 19. The rear of the latchplate 22 acts on an abutment 29 fast on the pin 25 to move the pin 25 against the bias of spring 28. The movement of the pin 25, in this way, unbridges the jaws 31, 31a of cup 18. It will be understood that with the boom at any one setting the cup of one end fitting will be engaged with the ball 19, while the jaws 31, 31a and plunger 25 of the other end fitting will hold the sail. In other words the lanyards of both fittings will be operated in turn to effect the respective disengagements.

With the arrangement as shown in the drawings there is an end fitting, embodying the invention, at each end of the boom. The lanyard 34 can be employed to simultaneously release the ball and cup joint and the plunger at each end of the boom. Thus, simultaneously, the boom is released from the mast, at one end of the boom, and the sail is released from the boom, at the other end of the boom, all in one movement.

What I claim as my invention and desire to secure by Letters Patent of the United States is:

1. A boom end fitting comprising a housing, the housing defining a socket for engagement over an end of a boom and one part of a two-part cup forming one element of a spherical type joint for releasable engagement with a ball member, another part of said cup pivotally mounted on said housing, resilient means biassing said other part of the two-part cup to a ball-engaging position, a pair of jaws on said housing and adapted to receive an eye fast with a sail which is to be used on conjunction with the boom, a withdrawable plunger bridging the gap between the jaws for holding the eye captive, said resilient biassing means also acting on said withdrawable plunger to hold it in a gap-bridging position, and releasing means operatively connected to said other part of said cup and also to said plunger to release the cup from the ball and the plunger from the jaws.

2. The combination of a boom; a fitting at each end of the boom, each fitting comprising a housing, the houson said housing, resilient means biassing said other part ofthe two-part cup to a ball-engaging position, a pair of jaws on said housing and adapted to receive an eye fast with a sail which is to be used in conjunction with the boom, a withdrawable plunger bridging the gap between the jaws for holding the eye captive, said resilient biassing means also acting on said withdrawable plunger to hold it in a gap-bridging position, and releasing means operatively connected to said other part of said cup and also to said plunger to release the cup from the ball and the plunger from the jaws; and an interconnection between the releasing means of the fittings at each end of the boom.

3. A boom end fitting comprising a housing defining a socket for engagement over an end of a boom, a cup on said housing and forming one element of a spherical 2,879,736 i p i type joint'for' releasable engagement with a ball member,

vresiliently biased latch means, for holding said element releasably engaged with the. ball, a pair of jaws on said housing to receive an eye fast with a sail which is to be used in conjunction with the boom, a resiliently biased withdrawable plunger bridging the gap between said jaws and for holding said eye captive, resilient biassing means "acting on said latch means and said plunger, and means operatively connected to said latch means and; to said plunger for releasing the cup from the bail member and the plunger'from the eye.

Larsen Nov/29, 1927 Plym p Mar. 30, 1954