GB2049594A

GB2049594A - Water craft propulsion

Info

Publication number: GB2049594A
Application number: GB7937150A
Authority: GB
Original assignee: TIPALDI A
Current assignee: TIPALDI A
Priority date: 1979-03-22
Filing date: 1979-10-26
Publication date: 1980-12-31

Abstract

A hand propelled water craft, e.g. a dinghy, skiff, raft or float, is provided with propelling means constituted by at least one member (11) having a pivotal middle portion (16) and two end portions one (12) of which is paddle-shaped and adapted to drive the craft when the other end portion (20) is manually moved, said paddle-shaped portion being underwater when the craft is in use in smooth water and adapted to oscillate around a pivotal bearing (14) which allows the paddle-shaped portion to swing so that the craft is propelled by an up and down movement of the free end of the paddle-shaped portion. <IMAGE>

Description

SPECIFICATION Water craft propulsion The present invention relates to water craft capable of being hand propelled, e.g. dinghies, skiffs, rafts, floats etc., especially those having a substantially flat stern in the form of, e.g., a transom; hereinafter these craft will be referred to as water craft.

Hitherto water craft have been propelled by various types of oars or paddles which, while hand held or supported by devices such as oarlocks but not otherwise attached to the craft, moved the craft forward by acting against the water in a direction generally opposite to that of the travel of the craft, the oars or paddles being alternately in and out of the water.

I have now found that it is possible to propel the water craft by a paddle-shaped member pivotally mounted horizontally at one end below the waterline; the pivotal mounting provides an axis of swing in a direction transverse to that of the travel of the craft and allows the free end of the paddle to move up and down under water. It is to be noted that the pivotal mounting could be constituted, for example, by a hinge pin, or it can be, e.g., in the form of strong flexible membrane or washer, e.g. of plastic or rubber, which allows the paddle to oscillate about an axis to propel the craft and steering to be effected by applying torsion to the membrane. Steering can be provided also by means of two independently operable paddle assemblies which are hinged to the craft, thus providing a fixed axis of swing for each paddle.

The present invention thus provides a hand propelled water craft equipped with propelling means constituted by at least one member having a pivotal middle portion and two end portions one of which is paddle-shaped and adapted to drive the craft when the other end portion is manually moved, said paddle-shaped portion being under water when the craft is in use in smooth water and adapted to oscillate around a pivotal bearing which allows the paddle to swing in a direction transverse to the direction of desired travel, so that the craft is propelled by an up and down movement of the free end of the paddle-shaped portion.

It will be appreciated that the paddle-shaped portion will be most efficiently used to propel the craft when it is under waterthroughout the time the craft is in use, but if the water is choppy, the paddleshaped portion is liable to leave the watertemporarily, but my invention includes use ofthe craft in choppy water.

In one form of the invention a single propelling means is provided, said means being pivotally mounted through a flexible washer affixed in water tight manner to seal an opening in a substantially vertical transom of the craft, so that the paddleshaped portion can be oscillated to propel the craft and steering can be effected by torsion of said means.

In another form of the invention two independently manually operable paddle assemblies are provided, each assembly being hingeably mounted on the craft in such a way that when both assemblies are operated in unison the craft is propelled forward, while operation of each assembly in disunison is able to effect steering of the craft.

The invention will now be described by reference to the accompanying diagrammatic drawings in which Fig. 1 is a perspective view of one embodiment of a water craft according to the present invention, Fig. 2 is an exploded view of the paddle assembly of the craft shown in Fig. 1, Fig. 3 is a plan view of another embodiment of the water craft according to the present invention, Fig. 4 is a side elevational view of the embodiment shown in Fig. 3, Fig. 5 is an enlarged and elevational view of the embodiment shown in Fig. 3, and Fig. 6 is an enlarged cross-sectional view taken along line Ill-Ill of Fig. 3 viewed in the direction of the arrows.

Referring first to Figs. 1 and 2, a water craft in the form of boat 7 has a vertical transom 8; this transom 8 is provided with a circular opening at its lower end so as to come below the waterline when the boat 7 is in use to allow a propelling means in the form of a paddle assembly 11 to be positioned to enable the boatto be propelled and steered as will be described below. The assembly 11 is constituted by a curved tubular lever 10 which is provided with a grip in the form of a cross piece 20 at one end and a hole 22 nearthe other end.The lever 10 is adapted to fit into a metal rod 16 having at each end one of two tappings 17,21. The circular opening in the transom 8 is completely covered by a circular rubber washer 14, whose diameter is largerthan that of the circular opening and which is bonded to themiddle of the rod 16; thewasher 14 is held in position bye'metal disk 15 provided with an aperture 24 having a diame terlargerthanthatofthe rod 16 to allow movement of the assembly as described below; it will be understood that the aperture 24 also acts as a kind of bearing for the rod 16 when this is moved.The disk 15 is firmly affixed, e.g. by means of screws (not shown), to the portion of the transom 8 surrounding the opening and makes a watertight seal with the washer 14. A flexible paddle 12 is bonded to a metal member 13 terminating in atubularend portion 18 having a hole 23 which hole is adapted to frt around rod 16 to register with the tapping 21. Two pins 19 are provided to allow the paddle assembly to be made integral in such a way as to enable propulsion of the craft when the grip 20 is manually moved using a pumping motion; steering may be effected by inclining the lever 10 as required. The aperture 24 in the disk 15 must be just sufficiently large to allow the amount of backlash necessary to propel andlor steer the craft.The washer 14, which is bonded in watertight mannerto the rod 16, must be sufficiently strong to allow repeated movement as described of the paddle assembly 11 without break or damage though it may be necessary to replace it after prolonged service. Moreover, the washer 14 must be sufficiently flexible to allow the paddle to be oscillated so that the free end can be moved in an up and down direction and also to allow torsion to be applied to allow the craft to be steered. Suitable rubber or plastic materials for this purpose are well knoirvn.

Referring now to Figs. 3 to 6, a boat 30 having a vertical transom 40 is provided with propelling means constituted bytwo independently operable paddle assemblies. For the sake of convenience, as the two assemblies are mirror images of one another, the construction of only one will be described in detail. A tubular member 31a comprises a handle portion 39a (see Fig. 3) at one end and a socket portion 41a (see Fig. 4) at the other end adapted to be fixed round a rod 32a which is integral with a metal leaf 34e of a hinge terminating in two tubular or eye members 35a higeably mounted on a hinge pin 36 common to both paddle assemblies.So as to immobilize the boat, if required, the tubular member 31a can be attached to the rod 32a and made integral with it by means ob a pin (not shown) adapted to fit into holes (not shown) provided in the portion 41a and rod 32a respectively. The hinge pin 36 is held in position on the transom 40 by two U-shaped brackets 37a, 37b which are screwed to the transom by means of screws (not shown). One each of plastic or rubber paddles 33a, 33b is firmly attached (e.g. by metal to rubber bondirig) to the associated metal leaf of its hinge. It is thus seen that each paddle assembly is independently operable by manually moving the members 31a, 31b, so that when both are moved in unison the boat will be propelled forward by the resulting oscillating movement of the paddles which are mounted on the transom below the waterline in such a way that the paddles remain substantially under water when the boat is travelling in calm water. Steering may be effected, e.g., by maintaining one paddle assembly steady and moving the other, though any operation in disunison will have some steering effect on the craft.

It will be understood that various other changes and modifications may be made in the practice of the invention without departing from the scope of the invention particularly as defined in the following

Claims

claims. For example, the present invention also provides the above propelling means adapted to be used in hand operated water craft. CLAIMS

1. A hand propelled water craft provided with propelling means constituted by at least one member having a pivotal middle portion and two end portions one of which is paddle-shaped and adapted to drive the craft when the other end portion is manually moved, said paddle-shaped portion being under water when the craft is in use in smooth water and adapted to oscillate around a pivotal bear ing which allows the paddle to swing in a direction transverse to the direction of desired travel, so that the craft is propelled by an up and down movement of the free end of the paddle-shaped portion.

2. A craft according to Claim 1, in which a single propelling means is provided, said means being pivotally mounted through a flexible washer affixed in watertight manner to seal an opening in a substantially vertical transom of the craft, so that the paddle-shaped portion can be oscillated to propel the craft and steering can be effected by torsion of said means.

3. A craft according to Claim 1, in which two independently manually operable paddle assemblies are provided, each assembly being hingeably mounted on the craft in such a way that when both assemblies are operated in unison the craft is propelled forward, while operation of each assembly in disunison is able to effect steering of the craft.

4. A hand propelled water craft provided with propelling means constituted by at least one member having a pivotal' middle portion and two end portions one of which is paddle-shaped and adapted to drive the craft when the other end portion is manually moved constructed and arranged substantially as described and shown in Figures 1 and 2 or 3 to 6 of the accompanying drawings.

5. Propelling means as defined in any one of the preceding claims adapted to be used in hand propelled water craft.