The invention concerns a boom and a boomhead for a windsurfer, the boom consisting of two arms which in one end - possibly demountably - are attached to a boomhead, consisting of two jaws, which are designed for clutching a mast and are mutually connecte by a joint, flexible like a hinge connection. This joint might be '•f designed as a hinge connection or an elastic piece of metal or plastic.

Such a windsurfer boom and boomhead are known from PCT publicatio no. WO 79/01078. In this known arrangement, the joint of the boomhead is placed in front of the jaws, i.e. opposite the part of the boomhead attached to or designed for attachment to the boom arms. When this known windurfer boom is mounted, the join of the boomhead is placed on the side of the mast, opposite th boom arms.

The sail being stretched between the mast and the end of the boo opposite the boomhead, the boom of this known invention will when stressed - tend to pull the end of the boom opposite th boomhead towards the mast and against the elasticity of the boo arms. This causes the boom arms to be pressed outwards (thei curvature increases), resulting in a reduced pressure of the jaw against the mast. A disadvantage of the known technique is thu that the strength of the attachment of the boom against the mas will decrease just as increasing wind force calls for mor strength of the attachment.

According to the invention, this disadvantage is eliminated, th joint being placed on the same side of the jaws as the part o the boomhead designed for attachment to the boom arms.

When the boom is mounted on the mast, the joint will be placed o the same side of the mast as the end of the boom opposite th boomhead, and (in accordance with the above explanation regardin the known technique) the stress will thus - contrary to wha applies to the known technique - increase the pressure of th jaws against the mast. Moreover, according to the invention mechanical locking devices etc. are no longer needed.

Now follows a detailed description of the invention, referring t the drawing, where

fig. 1 shows boom and sail mounted on a mast,

fig. 2 shows the known bomhead construction, seen from * above,

fig. 3 shows the boomhead according to the invention, also seen from above.

FIGURE 1

The rig consists of a mast (1), placed in a casing at the front edge of a sail (2). In the casing of the sail (2) there is an opening (3) designed for attachment of a boom (4) to the mast (1). The boom (4) consists of a boomhead (5) placed against the mast and of two boom arms (6 and 7) in the front end attached to the boomhead (5), and in the rear end to a mounting (11), to which the sail (2) is fastened. The boom (4) thus encircles the mast (1) and the sail (2).

FIGURE 2

The boom according to PCT publication no. WO 79/01078 consists of two boom arms (6 and 7), each connected to a jaw (8 and 9). Between the jaws (8 and 9) a mast (1) is held in position. In front of the mast (1), the jaws (8 and 9) are connected by a joint (10).

FIGURE 3

The boom according to the invention consists of two boom arms (6 and 7), each connected to a jaw (8 and 9). Between the jaws (8 and 9), a mast (1) is held in position. Behind the mast (1), the jaws (8 and 9) are connected by a joint (10) flexible like a hinge connection.