AU9711301A

AU9711301A - Detachable fin system

Info

Publication number: AU9711301A
Application number: AU97113/01A
Authority: AU
Inventors: David J. Smith
Original assignee: Smith David Jonathan
Current assignee: Smith David Jonathan
Priority date: 2000-12-08
Filing date: 2001-12-07
Publication date: 2002-06-13

Description

EDITORIAL NOTE No. 97113/01 Please note that page 1 is both a description and claim page 33 39 686 Al May.. 1985 DE.

1149184 MS Apr., 1969 GB.

1. A fin fixing assembly having one or more fixing elements adapted to be embedded in the craft, the elements having a fixing cavity therein adapted to receive a fixing formation.

A fin fixing assembly according to claim 1 wherein the location is intimate to the base.

3. A fin fixing assembly according to claim 1 wherein the fixing element is elongate in the longitudinal direction of the craft.

4. A fin fixing assembly for a craft, having one or more fixing elements adapted to be embedded in the craft, the elements having a fixing cavity therein adapted to receive a fixing formation.

A fin fixing assembly according to claim 4 wherein the fixing element is journalled within the base and locked in place with a socket head screw or similar mechanical fixing item Description BACKGROUND OF THE INVENTION The invention relates to a removable fin system for craft such as surfboards.

DESCRIPTION OF THE PRIOR ART In the manufacture of surfboards, a body of plastics foam material is shaped and then covered with a layer of fibre-reinforced resin, normally fiberglass.

One or more fins, most commonly three, are fixed to the board at the rear, normally by one of two methods, either by attaching the fins to the board by means of fibre reinforced resin around the base of the fin, or by the use of a so-called "fin box".

Each of these approaches has significant disadvantages, as discussed in Australian Patent No. 657456, which discloses a removable fin system for surfboards and the like in which tabs extending from the end surface of each removable fin are received in cavities of fixing plugs embedded in the board.

Obliquely extending grub screw are then tightened to extend into the cavity and bear against the side of each tab, locking the fin onto the board.

This system has been successfully employed and marketed but, while simple in design, requires a multitude of operations to install to keep the screw head free of sanding dust, and cutting and polishing compounds from finishing of the board, which may set in the screw head and lead to stripping of the screw head or key due to ill-fitting. Also, when used in conjunction with fiberglass fins the screw tip may chew into the fin tab, causing a divot point or burring of the tab. The present inventors consider that the existing system can be improved upon in terms of speed and simplicity of operation and installation.

Australian Patent Application No. 81502/94 proposed a fin fixing system in which tabs on the fin were held in corresponding cavities of embedded fixing elements by means of a tongue forced across by insertion of a plug member.

This system was marketed briefly but discontinued due to lack of reliability.

SUMMARY OF THE INVENTION The present invention seeks to provide a reliable and simple fin fixing system with the strength of the craft to which it is attached.

In one form, there is provided a surf fin fixing assembly for a surfcraft, having one or more fixing elements adapted to be embedded in the surfcraft, the elements having a fixing cavity therein adapted to receive a fixing formation, a surf fin having a pair of generally vertical lateral surfaces, an end surface and one or more fixing formations adapted to be received in the fixing cavities.

BRIEF DESCRIPTION OF THE DRAWINGS 1. A steering fin with a bonded flange or tongue extending from the mounting base with strength, length, thickness and depth suitable to retain the fin whilst maintaining the streamlines required between the base and object being steered.

2. A socket mounting (10) for permanent inclusion in the object to which a fin is to be mounted- The socket mounting having a thin rectangular slot to accept the fin tongue and a means offixing by an angled side mounted socket screw moulded into the socket mounting 3. A defined recess with depth, shape and direction, within which the socket mounting (10) is placed and bonded. The sides are profiled in such a manner to provide permanent bonding with it's substrate.

Description Previous fin attachment methods were either using a direct bond of a fin to the object being steered, a preformed slot into which a fin is attached or ribbed plasic plugs providing attachment for a detachable fin.

This invention is to use a base of material compatible with the object requiring the fin to be fitted and a specially manufactured fin with a bonded tongue to enable ease of replacing fins whilst maintaining a secure method of fixing I hereby claim a patent substantially as hereinbefore described.

Dated this day of December 2001 Signed: David Smith Of

Claims

4. A fin fixing assembly for a craft, having one or more fixing elements adapted to be embedded in the craft, the elements having a fixing cavity therein adapted to receive a fixing formation. A fin fixing assembly according to claim 4 wherein the fixing element is journalled within the base and locked in place with a socket head screw or similar mechanical fixing item Description BACKGROUND OF THE INVENTION The invention relates to a removable fin system for craft such as surfboards. DESCRIPTION OF THE PRIOR ART In the manufacture of surfboards, a body of plastics foam material is shaped and then covered with a layer of fibre-reinforced resin, normally fiberglass. One or more fins, most commonly three, are fixed to the board at the rear, normally by one of two methods, either by attaching the fins to the board by means of fibre reinforced resin around the base of the fin, or by the use of a so-called "fin box". Each of these approaches has significant disadvantages, as discussed in Australian Patent No. 657456, which discloses a removable fin system for surfboards and the like in which tabs extending from the end surface of each removable fin are received in cavities of fixing plugs embedded in the board. Obliquely extending grub screw are then tightened to extend into the cavity and bear against the side of each tab, locking the fin onto the board. This system has been successfully employed and marketed but, while simple