US3827392A

US3827392A - Water planing craft

Info

Publication number: US3827392A
Application number: US00274015A
Authority: US
Inventors: D Jones
Original assignee: Scooter Ski Ltd
Current assignee: Scooter Ski Ltd
Priority date: 1972-07-21
Filing date: 1972-07-21
Publication date: 1974-08-06
Anticipated expiration: 1991-08-06

Abstract

A planing water craft includes a hull having a longitudinally directed tunnel located on the centre line of the craft, the tunnel having a forward inlet and a rear outlet with the former disposed rearwardly of the centre of the hull, and there being a single resiliently-mounted propellor shaft in the tunnel driven from an engine resiliently mounted in a sealed engine compartment forwardly of the tunnel.

Description

United States Patent [191 Jones WATER PLANING CRAFT [75] Inventor: Dennis L. Jones, Breaston, England [73] Assignee: Scooter Ski Limited [22] Filed: July 21, 1972 [2]] Appl. No.: 274,015

[52] US. Cl. 115/70, 115/14 [51] Int. Cl B63h 11/02 [58] Field of Search 115/11, l2, 14, 15,34,

[56] References Cited UNITED STATES PATENTS 2,431,931 12/1947 Hall 248/9 2,595,863 5/1952 Loofbourrow 115/34 R 3,083,679 4/1963 Conover 248/8 3,292,373 12/1966 Tado 115/14 3,426,724 2/1969 Jacobson 115/12 R 1 Aug. 6, 1974 3,465,705 9/1969 Castoldi 1 15/12 R 3,470,843 10/1969 Satterthwaite et a1. 1 15/34 R 3,623,447 11/1971 Jacobson 115/12 R FOREIGN PATENTS OR APPLICATIONS 405,634 1/1934 Great Britain 115/14 Primary Examiner-Trygve M. Blix Assistant Examiner-Charles E. Frankfort Attorney, Agent, or Firm-Breitenfeld & Levine ABSTRACT A planing water craft includes a hull having a longitudinally directed tunnel located on the 'centre line of the craft, the tunnel having a forward inlet and a rear outlet with the former disposed rearwardly of the centre of the hull, and there being a single resilientlymounted propellor shaft in the tunnel driven from an engine resiliently mounted in a sealed engine compartment forwardly of the tunnel.

6 Claims, 3 Drawing Figures PAIENTEmuc 61974 SHEET 1 BF 2 mm a a WATER PLANING CRAFT The invention relates to planing water craft and especially to propulsion units therefor.

The invention provides a planing water craft including a hull having a longitudinally-directed tunnel lo cated on the centre line of the craft and accommodating a power driven impellor, the tunnel having an inlet opening disposed rearwardly of the centre of the hull and a rear outlet opening, and being of streamlined internal shape between said inlet opening and said outlet opening, an engine resiliently mounted in an engine compartment formed within the hull forwardly of said tunnel, the engine being coupled to the impellor by a single drive shaft, the engine compartment being sealed from said tunnel by a resilient sealing member, and said drive shaft being resiliently supported at or adjacent its rear end.

Said inlet opening is preferably horizontally disposed in the bottom of said hull and said outlet opening vertically disposed at the rear end of said tunnel, the tunnel being of generally arcuate form in longitudinal section, and the inlet opening being covered by a mesh screen or the like.

The craft may be steered in any desired manner but steering may advantageously be effected by means of twin rudders disposed one at each side of the outlet opening and coupled together for movement in unison under the control of a steering wheel, handlebars or the like.

The resilient mounting for the rear end of said drive shaft preferably comprises a support secured between the tunnel walls and shaped to reduce restriction to water flow. Preferably also the tunnel includes a removable lower portion disposed around the impellor by means of which access may be gained to the impellor and its rear mounting.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

FIG. 1 is a side elevation of a planing water craft with parts broken away to show internal details;

FIG. 2 is atop plan view of a detachable lower tunnel portion; and

FIG. 3 is a front view of the portion shown in FIG. 2.

Referring to the drawings, the craft includes a streamlined fibreglass hull 5 which is buoyant and selfstable when stationary and is provided with a seat 6 located on the centre line of the hull and astride which the user or rider of the craft sits withhis hands on a pair of handlebars 7 carried by a rotatable steering column 8 and his feet on foot wells one at each side of the seat. The craft is propelled by a water jet created by an impellor 9 driven by an internal combustion engine 10 mounted within the hull. Steering is effected by deflection of the water jet by means of a pair of rudders 11 located one at each side of the jet orifice and coupled together for movement in unison through a linkage actuated by rotation of the column 8.

The impellor 9 is located in an enclosed propulsion tunnel 12 the major part of which is formed integrally with the bottom of the hull 5. The tunnel is of streamlined internal shape to enable efficient throughflow of water from a forward inlet opening 13 in the base of the hull to a rear outlet opening 14 disposed immediately in front of and between the rudders 11. The inlet opening is covered by a grille 13a. Rotation of the impellor thus draws in water through the inlet 13 and forces it out the outlet 14 producing a water jet effective to pro.- pel the craft over the water. The output is such that the craft planes on the aft portion of the hull only. The rudders are enclosed and protected by a rear extension 12a of the tunnel.

The portion of the hull forwardly of the tunnel defines an engine compartment 15 which is separated from the tunnel by the upper wall of the intake region of the latter through which passes the propellor shaft 18. A resilient sealing member 16 surrounds the shaft where it passes through the tunnel wall and prevents ingress of water to the engine compartment. The shaft 18 is drivingly connected to the engine by a coupling 19 and the engine is resiliently supported on rubber mounting blocks 21 and by a rubber mounting ring 22 engaged in an aperture in a generally vertical supporting plate 20 adjacent the coupling 19. The resilience of the mounting ring 22 allows for slight misalignment of the shaft 18 and reduces vibration. The rear end of the shaft 18 is supported in a resilient bearing 23 supported between the walls of the tunnel, the bearing 23 and its supports being of streamlined shape to reduce interference with the water jet.

Thus the engine, propellor shaft and impellor are entirely resiliently mounted and vibration is thereby reduced. At the same time the nature of the tunnel and the disposition of the engine are such that only the single shaft 18 is required to couple the engine to the impellor.

The lower portion of the tunnel in the area of the impellor takes the form of a removable cover 25, shown in greater detail in FIGS. 2 and 3. The cover has an internal floor 26 of streamlined shape to correspond to that of the roof of the tunnel, and upwardly directed sides 27 provided with bolt holes 28 enabling the cover to be bolted to corresponding flanges associated with the tunnel. The cover is of fibreglass construction filled with a foamed synthetic plastics material for buoyancy and having metallic inserts at the bolt locations. This detachable cover portion enables ready access to be gained to the impellor and its bearing for purposes of repair and maintenance.

It should be noted that the propulsion tunnel is not open at the bottom (i.e. it is a tunnel as opposed to a duct) and is disposed well to the-rear of the craft with the inlet opening located rearwardly of the centre of the hull as viewed in FIG. 1. This ensures that even when the craft is planing at full speed the forward end of the tunnel does not rise clear of the water. This would permit introduction of air producing a loss of thrust and cavitation problems. Moreover the streamlined closed nature of the tunnel and the streamlining of the rear impellor supports allows a smooth through flow of water producing an efficient propulsion effect greater than can be achieved with water jet units proposed hitherto. The drive arrangement is also relatively vibration free and easily accessible for repair or maintenance. Initial assembly is also relatively simple and production costs are thereby reduced. In the embodiment the major part of the tunnel is integral with the hull of the craft, but the tunnel could alternatively comprise a separate unit adapted to be bolted or otherwise secured to a hull suitably adapted to receive it.

I claim:

1. A planing water craft including a hull, a seat located on the centre line of said hull and astride which the user of the craft sits, foot wells disposed one on each side of the seat, a longitudinally directed tunnel located on the centre line of the hull and accommodating a power driven impellor, the tunnel having a horizontally disposed inlet opening in the bottom thereof rearwardly of the centre of the hull and a vertically disposed outlet opening at the rear end of said tunnel, the tunnel being of generally arcuate form in longitudinal section and of streamlined internal shape between said inlet opening and said outlet opening, an engine compartment formed within the hull forwardly of said tunnel, an engine in said engine compartment, resilient mounting means for securing said engine with respect to said hull, a wall between said engine compartment and tunnel, an openingin said wall, a single drive shaft passing through said opening to couple said engine to said impeller, a resilient member in said opening surrounding said shaft, said member serving both to seal said opening and provide a bearing for said shaft, and

resilient mounting means for supporting the rear end of said shaft with respect to said hull.

2. A planing water craft according to claim 1 wherein said inlet opening is covered by a mesh screen.

3. A planing water craft according to claim 1 wherein at least the major part of said tunnel is formed integrally with said hull.

4. A planing water craft according to claim 1 wherein said resilient mounting for the rear end of said drive shaft comprises a support secured between the tunnel walls and shaped to reduce restriction to water flow.

5. A planing water craft according to claim 1 including a removable lower portion disposed around the impellor by means of which access may be gained to the impellor and its rear mounting.

6. A planing water craft according to claim 1 including twin rudders disposed one at each side of the outlet opening and coupled together for movement in unison under the control of a manual steering member.

Claims

1. A planing water craft including a hull, a seat located on the centre line of said hull and astride which the user of the craft sits, foot wells disposed one on each side of the seat, a longitudinally directed tunnel loCated on the centre line of the hull and accommodating a power driven impellor, the tunnel having a horizontally disposed inlet opening in the bottom thereof rearwardly of the centre of the hull and a vertically disposed outlet opening at the rear end of said tunnel, the tunnel being of generally arcuate form in longitudinal section and of streamlined internal shape between said inlet opening and said outlet opening, an engine compartment formed within the hull forwardly of said tunnel, an engine in said engine compartment, resilient mounting means for securing said engine with respect to said hull, a wall between said engine compartment and tunnel, an opening in said wall, a single drive shaft passing through said opening to couple said engine to said impeller, a resilient member in said opening surrounding said shaft, said member serving both to seal said opening and provide a bearing for said shaft, and resilient mounting means for supporting the rear end of said shaft with respect to said hull.