Patent Application
20120132119
The present invention is related to a supplementary device to improve the steering and directional control of any water jet powered craft through a novel means of increasing the laminar flow vortex through deflection by creating an extension of the relative position of the exit point of the stream by virtue of a channel in the inside of the vertical component(s), by an innovative supplemental rudder design, which easily attaches to any water-jet powered craft utilizing a controllable directional nozzle for steering, and may or may not incorporate a thrust reversal shroud to provide the vessel with reverse capability. The torsionally rotating mounting device is such that it is adjustable to increase or decrease the down force or moment arm with relation to the pivot point for precise adjustment for almost every design of water-jet driven vessel from single passenger ski craft to multiple passenger ski-style vessels, furthermore incorporating single and twin powered jet boat style vessels.
To provide background, the low speed directional change capability of a water-jet driven craft is directly proportional to the force and volumetric flow rate provided by the thrust of the water jet propulsion system. At slow or idle speed, this force is minimal, resulting in sluggish steering response, which reduces control of the craft when idling, docking or in the vicinity of other watercraft. The reduction or minimal ability to control of the vessel reduces the capability of the operator to safely maneuver the craft, and has been responsible for numerous accidents, personal injuries, and monetary damages. Because most of the vessels are not equipped with any type of braking system, it is imperative that the operator be in control of the vessel at all times and speeds. In a 1998 report, the National Transportation Safety Board criticized the basic design of all personal watercraft (PWC), reporting that PWCs have no braking mechanism and that they coast to a stop, and while coasting, there is no turning ability. Many experts concur that what makes PWCs so dangerous is the fact that it will not steer when the operator lets off the throttle. Being rudderless, when the throttle is off, a speeding jet ski or boat can't stop, nor turn, leaving the operator with no control.
A growing number of safety experts believe that, converse to industry claims, the vehicles themselves, not simply the riders, cause copious injuries and fatalities throughout the U.S. These experts believe those PWCs are a danger, not only to their own riders, but to swimmers, boaters, indeed, anyone who may be in the crafts vicinity. There is much evidence to support that hypothesis.
According to the 1999 yearly report from the California Department of Boating and Waterways, collisions between personal watercraft and vessels other than PWCs, the PWC operator was nearly 3 times as likely to be exclusively at fault.
In 1999 personal watercraft were 18 percent of boats, but were involved in 44 percent of injuries in California. In 2000 they were 19 percent of registered boats, involved in 45 percent of injuries. The PWC is the only vessel where the leading cause of fatality is not drowning. In contrast to boating accidents, most fatal PWC accident victims die from blunt-force trauma. Seventy-five percent of PWC accidents are collisions.
The named invention addresses many aspects of these concerns, creating a safer, more controlled craft. It is clear that if this device ever becomes standard equipment, or mandated for use, that countless lives can be saved, and fatal and incapacitating accidents greatly reduced.
The named invention relates to the steering and control of watercraft vessels which are propelled by water-jet style systems.
Over the last two decades, water jet propulsion units have become popular for recreational water craft. These craft are propelled by two or four stroke gasoline engine (in most instances) in connection with an impeller housed in a tubular chamber, the forward end of which draws in the water and the rearward end which expels it to provide thrust to propel the craft or vessel. In most instances a tubular nozzle is attached to the discharge end which pivots from side to side to provide steering capability. In fewer cases a deflector plate is provided at the exhaust end to deflect the jet flow to one side or the other of the craft.
A variety of different steering systems have been used in connection with water-jet powered craft.
U.S. Pat. No. 3,982,493 to Cronin illustrates a skid control mechanism having longitudinally hinged flaps mounted to opposite sides of the boat bottom. The flaps are designed to deflect into an open, water-engaging position to improve control when making high speed turns.
U.S. Pat. No. 5,437,568 to Kobayashi illustrates a water jet drive system having an integrated rudder system.
U.S. Pat. No. 4,004,536 to Bernier reveals an anti-skid system in which an elongated vane extends along each side of the hull of the water craft.
U.S. Pat. No. 4,949,662 to Kobayashi and U.S. Pat. No. 6,086,437 to Murray illustrate steering systems for personal water craft.
In the Kobayashi U.S. Pat. No. 4,949,662, the steering system includes a rudder mounted forward in the hull, which is out of the water at high speeds and immersed at low speeds for assisting in low speeding steering.
The Murray patent relates to a blow back rudder consisting of a rudder blade, a rudder shaft and a plate assembly that is pivotally mounted to a jet nozzle. The plate assembly pivots the rudder shaft and the rudder blade away from the exhaust port of the jet nozzle and out of the water stream in the non-deployed position.
Another system for steering a jet powered water craft at low speeds is revealed in U.S. Pat. No. 3,976,026 to Eastling.
In this system, the jet power unit of a water craft is provided with a steering plate which is deflectable upwards, but which is continuously oriented in the direction of, but spaced below, the flow of water from the jet.
Safe operation of Water craft remains a high priority of all concerned operators and agencies responsible for watercraft safety.
According to U.S. Coast Guard statistics, water-jet powered craft account for 36% of the vessels involved in marine accidents. These water craft can travel at speeds in excess 60 mph and rapidly spin 180 or 360 degrees in the water. Additionally, water-jet powered personal water craft operators are very exposed with almost no bodily protection. In light of these facts, control of water-jet powered personal water craft is a critical factor in reducing accidents occurring during operation.
A recent study by the National Transportation Safety Board and the United States Coast Guard has indicated that the lack of off-throttle steering is a contributing factor in many personal water craft accidents. In almost all such craft, the only steering ability is that provided by steering the thruster jet nozzle. Supplemental low speed devices that steer the personal water craft at low or part throttle positions are not currently available on commercial models. There is a clear need for water jets powered craft steering system which operates at low throttle or idle, and can easily be incorporated into current craft as is the case with the present named invention. It is of the highest concern to operators of these type craft to have the ability to control these vessels at slow speed approaches to docks, other vessels, and during loading and unloading. Many of the accidents documented occur during these low speed encounters when control of the vessel is inadequate or minimal.
Therefore, it is an object of the revealed invention to provide a steering system for a water-jet propelled water craft.
Further it is an object of the revealed device to provide a steering system as described above which improved low speed controllability.
It is yet another object of the present invention to be easily incorporated into the existing steering system of the water craft.
It is yet another object of the present invention to provide an improved method of water craft steering.
The mentioned objects are attained by the steering system and method of the present invention.
Other details of the revealed invention as well as further advantages thereto, are shown in the following detailed description and the accompanying drawings.
Although this invention has been shown and described with respect to detailed embodiments thereof, it will be appreciated and understood by those skilled in the art that a range of changes in appearance and features thereof may be made without departing from the spirit and scope of the claimed invention.
