Vibration damper for an electric trolling motor

Abstract

The invention is an accessory vibration damper that is applied over the diameter of any submersible electric motor housing of any modern electric trolling motor. Vibration damper is molded as a single unitary piece of an elastomeric compound that can have plural appendages placed perpependicular to the rotating armature of motor. Said appendages counteract the frequency range of vibrations produced while electric trolling motor is under propulsion.

Description

THE FIELD OF THE INVENTION

The present invention is an accessory device used for dampening vibrations created by an electric trolling motor to help improve the anglers chances of catching more fish.

BACKGROUND OF INVENTION

It has been observed by countless fishermen, that the slight noise generated by an electric trolling motor under propulsion can spook bass off their beds. Modern fishing tackle includes crankbaits and buzzbaits which use vibrations to attract the game fish. These vibrations as slight as they are alert the fish to the bait, but can be canceled out by an electric trolling motors vibrations. Thus making the bait much less effective and reducing the chances for catching fish.

DISCUSSION OF PRIOR ART

Person skilled in the art would be aware of many techniques that can be employed to dampen vibration and reduce sound. Therefore it would be understood that an electric trolling motor rotating an impeller at any load would-be a source of vibration and sound at certain frequencies in a body of water within a general fishing proximity. The following patents are a small representation of the various methods taught to dampen vibrations in vibration sensitive equipment, engines, transmissions, shafts, and impellers. Most of these designs employee the use of some form or shape of an elastomeric material to modify the vibrations set up in the systems and situations described herein as follows:

U.S. Pat. No. 7,293,755 Miyahara, et al. 2007. A vibration isolation device comprising a first member for attachment to a vibratory source and a second member for attachment to a support body on which a vibratory source is to be mounted and an elastic member interconnecting the first attachment member and the second attachment member.

U.S. Pat. No. 7,267,318 Kennard, IV 2007. A vibration control device to reduce the effects of vibrations on vibration sensitive equipment where said device is a unitary piece of a soft, pliable substance having a hardened round crown portion and in operative contact between support surface and equipment.

U.S. Pat. No. 7,243,895 Saito 2007. A damping and mounting structure for a motor where the use of an elastic material for vibration damping is taught.

U.S. Pat. No. 7,175,150 Chi 2007. A compound vibration damper assembly consisting of vertical and horizontal damping units working-together to dampen vibration forces in X-, Y-, and Z-directions that teaches the use of elastomers in the base and top plates of said assembly.

U.S. Pat. No. 6,024,615 Eichinger 2000. A vibration damping system that incorporates an inertia mass that is disposed inside the portion of a rotating tubular shaft of an impeller. The mass is attached for rotation by three or more elastomeric members that attach to the inside surface of the rotatable shaft.

U.S. Pat. No. 5,975,972 Wilmsen 1999. The invention is a vibration damper having a housing formed by a shell part and a base part wherein a pressure cavity is located and partially delimited by a membrane made of an elastomer material. Enclosed within the membrane is a dome-shaped plate made of spring steel and attached to a pin that passes through the membrane and protrudes through the housing to the outside.

U.S. Pat. No. 4,884,666 Stahl 1989. The use of a torsional damper and mounting adapter is taught as a way dampen shaft vibrations and sound when a pair of shafts are coupled at the ends.

U.S. Pat. No. 5,231,893 Sisco et al 1993. The device is taught as a dual mode damper used to reduce crankshaft vibrations. An elastomer member is placed between a hub and a annular inertia member. The hub is configured to mate to the accessory drive end of the crankshaft to reduce crankshaft bending vibrations.

U.S. Pat. No. 4,905,956 Zemlicka et al 1990. Discloses a fluid mounting system for a marine engine. The mounting system is a combination of a solid elastomer and a fluid dampening means by which to greatly improve vibration isolation and cushioning under normal shock loads.

U.S. Pat. No. 4,200,004 Bremer 1980. Discloses a zero slip torsional vibration damper consisting of an inertia ring coupled to a hub by means of an elastomer member. The hub is then coupled to a shaft subject to torsional vibrations. The outer most portion of the elastomer carries angular spaced pockets into which a damper liquid is placed to dampen torsional vibrations.

U.S. Pat. No. 5,095,786 Bellinghausen et al 1992. Teaches a method by which brake lathe vibrations can be dampened during turning of stock.

U.S. Pat. No. 4,962,677 Withers 1990. Discloses a torsional vibration damper used to dampen harmonic vibration frequencies set up in the crankshaft of a reciprocating internal combustion engine. Device consists of a hub capable of being mounted to a crankshaft and a ring of elastomeric material placed over diameter of hub and an inertia ring press fitted over elastomeric ring.

U.S. Pat. No. 4,044,628 Jacks 1977. Discloses a torsional vibration damper to reduce vibrations set up in a shaft under power. The damper is formed as an integral unit by casting it from a metal such as cast iron in a disc like shape with spiral slots. The disc has three concentric zones; an inner central zone, an outer annular zone, and an intermediate spring zone. The spring zone is the area consisting of the spiral slots having a predetermined size and shape to provide the desired damping effect and extending axially through the disc and radially between the inner and outer zones to provide spirally arranged overlapping webbed portions which act as torsional springs or shock absorbers due to inherent resiliency.

Vibration damping of certain rotating systems can be constrained due to the requirements, the environment, and spacial restrictions that would prevent the use of known vibration damping means. Therefore it would be significantly beneficial if by which a means to dampen the vibrations and sound generated by an electric trolling motor could be provided that would not increase the internal dimensions of said motor or increase the power of said motor to make up for losses caused by extra mass of a harmonic balancer.

SUMMARY OF THE INVENTION

In one preferred embodiment of the present invention the vibration damping device is molded out of a soft, flexible thermoplastic elastomer with a central hub that can stretch to fit the outside diameter of any modern electric trolling motor housing. From this central hub extend two or more appendages outwardly with integral masses at the distal end to provide the desired vibration and sound damping. The form and shape of any preferred embodiment of the invention described herein could also lend itself to other dynamic and static attachments to a vibration excited surface or media to reduce vibration and sound.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows-the vibration damping device (01) as described in Claim 1.

FIG. 2 shows vibration damping device (01) mounted over the outside diameter of submersible electric motor (12) at the lower half of electric trolling motor assembly (20).

FIG. 3 shows a preferred embodiment of dampening device (01) as described in Claim 8.

FIG. 4 shows complete electric trolling motor assembly (20) with a preferred embodiment of vibration damping device (01) installed over the outside diameter of submersible electric motor (12).

FIG. 5 shows another preferred embodiment of dampening device (01) as described in Claim 9.

FIG. 6 shows complete electric trolling motor assembly (20) with another preferred embodiment of vibration damping device (01) installed over the outside diameter of submersible electric motor (12).

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric-view of vibration damping device (01) with inside diameter of cylindrical hub (02) to receive onto the outside diameter of submersible electric motor (12) and with two appendages (03) spaced around the circumference of vibration damping device (01). FIG. 2 is an isometric view from as seen from top-left of lower half of electric trolling motor assembly (20) showing vibration damper (01) placed over outside diameter of submersible electric motor (12). Also shown is the propeller (11) mounted on the output shaft of submersible electric motor (12), and support tube (13) affixed to housing of submersible electric motor (12) which is used to mount electric trolling motor assembly (20) to the side of a boat.

FIG. 3 is a top view of a preferred embodiment of the vibration damping device (01) showing four integral masses (04) at the distal ends of appendages (03) extending away from outer diameter of vibration damping device (01) and the inside diameter cylindrical hub (02) to receive onto outside diameter of submersible electric motor (12).

FIG. 4 is an isometric view as seen from the top-left of complete electric trolling motor assembly (20) showing a preferred embodiment of vibration damping device (01) installed over the outer diameter of the submersible electric motor (12) and held in place by the friction caused by the diameter differential between the inside diameter of cylindrical hub (02) of the vibration damping device (01) and the outside diameter of the submersible electric motor (12). Also shown is the propeller (11), support tube (13), and the variable speed control (14) of electric trolling motor assembly (20).

FIG. 5 is an isometric view of another preferred embodiment of the vibration damping device (01) as seen from the top showing the plural appendages (03) that connect the inner diameter of cylindrical hub (02) of the vibration damping device (01) to the continuous peripheral mass (05).

FIG. 6 is an isometric view as seen from the top-right of complete electric trolling motor assembly (20) showing another preferred embodiment of the vibration damper (01) installed over the outer diameter of the submersible electric motor (12). Also shown is the support tube (13) which connects the submersible electric motor (12) to the variable speed control (14) of the electric trolling motor assembly (20).

SPECIFICATION OF THE INVENTION

The device discussed in the following Utility Patent is a novel invention that will help mostly bass and pan fish anglers who use electric trolling motors for maneuvering around in fish habitat. It has been observed that electric trolling motors have spooked bass off of their beds and have taught bass that have been caught and released numerous times to not go after lures or bait when an electric trolling motor is in use. The device is a vibration damper that can be installed over the outside diameter of an electric trolling motor to reduce vibration and noise resulting in more chances to catch fish. The device will be molded as a singular unit of a soft thermoplastic elastomer which will have a selected hardness for the best vibration damping qualities. As the device is somewhat elastic it can easily be stretched over the propeller and electric trolling motor housing and hold in place on its own. Device can have two or more appendages around the circumference, with or without a perimeter mass or masses to modify vibration frequencies and reduce sound generated by the electric trolling motor while under power.

Claims

1.) A device (01) used to dampen vibrations and sound generated by the propulsion of an electric trolling motor assembly (20) comprising of:

a flexible thermoplastic elastomer compound;

molded as a single unit;

a cylindrical hub (02) with an inner diameter opening through center axis;

two or more appendages (03) extending out from cylindrical hub (02).

2.) The device (01) from claim 1 in which flexible thermoplastic elastomer compound is in the hardness range of 30 Shore OO to 80 Shore A.

3.) The device (01) from claim 1 in which cylindrical hub (02) can stretch its diameter as much as five times.

4.) The device (01) from claim 1 in which the inside diameter of cylindrical hub (02) is received onto outside diameter of submersible electric trolling motor housing (12) and held by friction due to constrictive forces caused by the diameter differential.

5.) The device (01) from claim 1 in which appendages (03) can be non-uniform in length.

6.) The device (01) from claim 1 in which appendages (03) can be non-uniform in thickness.

7.) The device (01) from claim 1 in which the appendages (03) can be spaced randomly around circumference of cylindrical hub (02).

8.) A damping device (01) used to reduce the vibrations and sound generated by an electric trolling motor assembly (20) under propulsion comprising:

a thermoplastic elastomer;

homogeneous throughout;

a cylindrical hub (02) with inner diameter sized to receive submersible electric trolling motor housing (12);

with two or more appendages (03) extending out from cylindrical hub;

with integral masses (04) at distal end of appendages (03).

9.) An electric trolling motor assembly (20) in combination with accessory damping device (01) installed over the outside diameter of submersible electric motor housing (12) comprising the following:

a singular molded unit of an elastomer material;

with a hollow cylindrical hub (02);

with two or more appendages (03) extending out from cylindrical hub;

with a continuous peripheral mass (05) connecting distal ends of appendages (03);

to modify the vibration frequencies generated by the rotating armature of the submersible electric motor (12).