Energy absorbing support for downrigger weight

An energy absorbing member for use in suspending a weight to a downrigger assembly for fishing. The member is formed of a viscoelastic material.

BACKGROUND

This application relates to fishing equipment, and in particular to suspending weights used to position a lure or bait at a desired depth in the water. In many instances when fishing it is often necessary to position the lure or bait at a predetermined depth beneath the surface of the water. In many cases this depth can be far below the surface. If trolling a great deal of weight can be required.

The downrigger is typically a winch like apparatus that includes a line or cable wound on a spool and that can be fed out to a desired length. The cable terminates at a fixture that includes a first attachment point for a weight and a second attachment point for a fishing line. A weight is attached to the terminal fixture. The fishing line that includes the lure or bait is also attached to the terminal fixture by way of a releasable clip. The releasable clip is designed so that the pressure applied to the fishing line when a fish strikes the lure releases the fishing line from the terminal fixture. The fisherman is then left to play and land the fish without the significant added weight of the downrigger weight.

It is normal practice to attach the downrigger weight to the terminal fixture by what is referred to as a snubber. When fishing in the ocean or other large bodies of water waves often cause sudden movement of the boat and the attached arm that suspends the downrigger. If the downrigger weight is “rigidly” attached to the terminal fixture the sudden movement of the boat can transmit sharp shocks to the fishing line and cause it to break or to release from the terminal device. A snubber is used to prevent those shocks from breaking the relatively light fishing line or prematurely releasing the fishing line from the terminal device. Snubbers also serve as a severable link between the weight and the downrigger in case the weight becomes entangled and can't be freed. In addition the snubber will electrically isolate the weight from the remainder of the downrigger and fishing equipment.

Prior art snubbers consist of a single strand of elastic material fitted with a connector on each end. The connectors are used to attach the snubber to the terminal device on one end and the downrigger weight on the other end. Prior art snubbers are problematic for several reasons. First, they stretch too much, especially when heavy downrigger weights are used. As the weights are lifted from the water prior art snubbers stretch to the point where either the weight is not clear of the water. Even if the weight is clear of the water, in rough water it is prone to violent swings that can result in the weight hitting and damaging the boat. This poses a significant risk to the boat and its occupants, especially when fishing far from shore.

Prior art snubbers are also deficient in that while they are elastic and spread out the sharp energy spikes associated with sudden shocks, they don't effectively reduce the total energy delivered to the downrigger. The energy is delivered in a series of lower energy spikes, i.e. bounces, as the elastic snubber stretches and contracts. While it is better that the weight bounces several times and transmits less shock to the downrigger with each bounce, it would be preferable if the shock energy could be dissipated.

A need therefore exists for an improved snubber that provides shock and electrical isolation between the weight and downrigger, and which overcomes the shortcomings of the prior art.

SUMMARY OF THE INVENTION

This invention overcomes the shortcomings of the prior art by providing an improved snubber that is economical to manufacture, that is easily attached to the terminal fixture of the downrigger and to the weight without the need for connectors attached to the snubber during manufacture, and that more effectively isolates the terminal fixture from shocks resulting from sudden relative movement between terminal fixture and the weight.

The invention is embodied in a continuous loop of polymeric material that is elastic and which in addition is dissipates significant amounts of energy as it deforms and returns to its normal shape under the forces associated with the sudden relative movement between the boat and the weight. In this way a snubber according to the invention does not merely reduce the magnitude of energy spikes transmitted to the downrigger, but in addition reduces the total energy transmitted to the downrigger. A snubber according to the invention embodies an additional advantage in that a single snubber can be used with different weights by being configured to suspend the weight with 2 strands of material or 4 strands of material.

These and other aspects of the invention will be described by reference to the drawings.

DETAILED DESCRIPTION

Turning now toFIG. 1, a downrigger is shown generally at10, and includes an arm12, a winch14, a cable16, and a terminal fixture18. Arm12is mounted on the gunwhale of a boat22.FIG. 2shows a typical terminal fixture18that includes a connector24to attach terminal fixture18to cable16, a release mechanism26that attaches the fishing line28to terminal fixture18, and a connector30to which a prior art snubber32is attached. Snubber32includes a body34and top and bottom connectors36and38. Weight39is attached to snubber32by connector38.

Turning now toFIGS. 3-6a snubber according to the invention is shown at40. Snubber40is a continuous loop of a flexible, viscoelastic material. Snubber40can be configured to suspend weight39by two strands of material (FIG. 4), or in a 4-strand configuration (FIG. 5). In the two strand configuration one end of snubber40is passed through a connector42on weight39and back through itself to form cinch connector42in a loop44. The free end41of snubber40is then connected to connector38to attach weight39to terminal fixture18.

Referring toFIG. 5, when configured in a 4-strand configuration snubber40is inserted through connector42on weight39and then both ends41and43of snubber40are connected to lower connector38of terminal fixture18.

In preferred embodiment of the invention snubber40is made from a viscoelastic material known as EPDM, ethylene-propylene-diene monomer, that is widely available. EPDM has been widely used in automotive weather-stripping and seals, glass-run channel, radiator, garden and appliance hose, tubing, belts, electrical insulation, roofing membrane, rubber mechanical goods, plastic impact modification, thermoplastic vulcanisates and motor oil additive applications. However, the combination of elasticity and energy dissipation described above with reference to the invention have not previously been recognized in these materials, and have not been recognized as advantageous in this application.

The snubber can be of any diameter or length. In one preferred embodiment the diameter is 0.23″ and the total length is 11″, although the invention is not limited to any particular dimension. While the preferred embodiment makes use of EDPM having a durometer hardness of 70 durometer, other viscoelastic materials of similar elastic and viscoelastic properties could be substituted without departing from the scope of the invention.

In the preferred embodiment of the invention the loop has a circular cross sectional shape, although the invention is not limited to any particular cross-sectional shape. In addition in preferred embodiments of the invention the loop is solid and not hollow, although once again the invention encompasses a loop of hollow material as well.

The snubber of the present invention provides significant advantages over the prior art. The combination of configuration and material provides greater dampening while also providing significant energy dissipation. It achieves these advantages while undergoing less stretching and thereby avoids the stretching-related problems associated with prior art snubbers.

While the invention has been described by reference to preferred embodiments, those of skill in the art will appreciate that the invention can be modified in various aspects without departing from the scope of the invention.