Abstract:
A watercraft has an engine that is controlled by an electronic control unit and the watercraft includes a security system. The security system includes a portable transmitter unit, and also includes a mounted receiver. The portable unit is waterproof and is buoyant. The portable unit includes a housing of transparent material that allows a user to see whether water has entered the portable unit. The security system has an antenna that provides improved reception between the portable transmitter unit and the mounted receiver.

Description:
PRIORITY INFORMATION  
       [0001]     This application is based on and claims priority to Japanese Patent Application No. 2004-081930, filed Mar. 22, 2004, the entire content of which is hereby expressly incorporated by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention generally relates to a control system for controlling a marine engine, and more particularly relates to an improved control system that controls a marine engine using a security system that has various modes of operation and that includes a transmitter and a receiver.  
         [0004]     2. Description of the Related Art  
         [0005]     Watercraft have been provided with an automatic control system using a transmitter that can remotely communicate with a receiver on the watercraft to allow an engine of the watercraft to start. Typically, an ID code is applied to identify whether a transmitter is the true key that is accessible to an associated receiver. Unless the system determines that the ID code is true, the person who has tried to use the key is not allowed to start the engine. Japanese Patent Publication No. 2001-254549 discloses examples of such watercraft systems.  
         [0006]     Small watercraft employ an engine to power the vehicle. For example, in a personal watercraft (PWC), a hull of the watercraft typically defines a rider&#39;s area above an engine compartment. An internal combustion engine powers a jet propulsion unit that propels the watercraft by discharging water rearward. The engine lies within the engine compartment in front of a tunnel, which is formed on an underside of the hull. At least part of the jet propulsion unit is placed within the tunnel and includes an impeller that is driven by the engine.  
       SUMMARY OF THE INVENTION  
       [0007]     One aspect of embodiments described herein is a watercraft that includes a hull, a seat, a control mast, and an engine disposed within the hull. The watercraft includes a controller that communicates with at least one engine parameter and that is configured to control engine operation. A security system in the watercraft is configured to communicate with the engine controller. A receiver communicates with the security system. A portable transmitter transmits at least one signal to the receiver. The portable transmitter comprises at least one sealed airtight cavity that maintains a density of the portable transmitter below the density of water. The security system determines how the engine controller controls the engine in response to a signal received from the receiver. The receiver is located in a remote location above the water level of the watercraft and adjacent to an access opening.  
         [0008]     In certain embodiments, the signal sent by the transmitter is a signal that prohibits engine operation. In other embodiments, the signal sent by the transmitter is a signal that permits engine operation. In other embodiments, the signal sent by the transmitter is a signal that limits engine operation.  
         [0009]     Preferably, the transmitter is removably mounted to the watercraft and the transmitter communicates by radio waves with the receiver. In particular embodiments, the transmitter is rectangular. The transmitter preferable includes a transmitter housing that is at least partially transparent.  
         [0010]     Preferably, the receiver has an antenna that extends from the receiver. In certain embodiments, the antenna is formed in a substantially closed loop configuration. Also preferably, the antenna includes a connector to extend the antenna.  
         [0011]     Another aspect in accordance with embodiments disclosed herein is a watercraft that includes a hull, a seat, a control mast, and an engine disposed within the hull. The watercraft includes a controller that communicates with at least one engine parameter and that is configured to control engine operation. A security system in the watercraft is configured to communicate with the engine controller. A receiver in the watercraft communicates with the security system. A portable transmitter transmits at least one signal to the receiver. The portable transmitter comprises a housing that it is at least partially transparent. The security system determines how the engine controller controls the engine in response to a signal received from the receiver. The receiver is located in a remote location above the water level of the watercraft and adjacent to an access opening.  
         [0012]     In one preferred embodiment, the signal sent by the transmitter is a signal that prohibits engine operation. In another preferred embodiment, the signal sent by the transmitter is a signal that permits engine operation. In another preferred embodiment, the signal sent by the transmitter is a signal that limits engine operation.  
         [0013]     Preferably, the transmitter is rectangular. Also preferably, the transmitter is buoyant. In certain preferred embodiments, the transmitter is removably mounted to the watercraft, and the transmitter communicates by radio waves with the receiver.  
         [0014]     Further aspects, features and advantages of this invention will become apparent from the detailed description of the preferred embodiments which follow. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]     The foregoing features, aspects, and advantages of the present invention are described below with reference to the drawings of several preferred embodiments that are intended to illustrate and not to limit the invention, in which:  
         [0016]      FIG. 1  is a side elevational and sectioned view of an engine-powered personal watercraft that has a security system comprising a receiver and a portable transmitter unit that are arranged and configured in accordance with certain features, aspects and advantages of the present invention;  
         [0017]      FIG. 2  is a front sectioned view of the watercraft of  FIG. 1  taken along the line A-A of  FIG. 1 ;  
         [0018]      FIG. 3  is a front sectioned view of the watercraft of  FIG. 1  taken along the line B-B of  FIG. 1 ;  
         [0019]      FIG. 4  is a perspective view of an enclosed compartment on the personal watercraft that has a receptacle configured to hold the portable transmitter;  
         [0020]      FIG. 5  is a schematic view of the security system and illustrates the interaction between the transmitter and the receiver;  
         [0021]      FIG. 6  is a cross-sectional view of the portable transmitter unit of the security system of  FIG. 1  with several of the internal components of the portable unit (e.g. a battery and various buttons) shown;  
         [0022]      FIG. 7  is an enlarged partial view of various parts and a coupling mechanism of the portable unit;  
         [0023]      FIG. 8  is a front plan view of the portable unit illustrating various buttons and an exemplifying size of the portable unit with respect to an operator&#39;s hand;  
         [0024]      FIG. 9  is a rear plan view of the portable unit of  FIG. 8  illustrating the presence of water droplets that are visible through the transparent housing;  
         [0025]      FIG. 10A  is front elevational view illustrating a rectangular shape of the portable unit configured in accordance with certain features, aspects and advantages of the present invention;  
         [0026]      FIG. 10B  is a front elevational view illustrating an hourglass shape of the portable unit configured in accordance with certain features, aspects and advantages of the present invention;  
         [0027]      FIG. 11A  is a front elevational view of the rectangular shaped portable unit illustrating various buttons and exemplifying the size of the portable unit with respect to an operator hand;  
         [0028]      FIG. 11B  is a front elevational view of the hourglass shaped portable unit illustrating various buttons and exemplifying the size of the portable unit with respect to an operator hand;  
         [0029]      FIG. 12A  is a front elevational view illustrating another shape of the portable unit configured in accordance with certain features, aspects and advantages of the present invention;  
         [0030]      FIG. 12B  is a front elevational view illustrating another shape of the portable unit configured in accordance with certain features, aspects and advantages of the present invention;  
         [0031]      FIG. 13  is a schematic diagram that illustrates the control device for the watercraft, wherein various components are shown, including a main unit, an electronic control section, and a security indicator;  
         [0032]      FIG. 14  is a flow diagram that illustrates the communication between the portable unit, the main unit, the electronic control section, and a display section;  
         [0033]      FIG. 15  illustrates a diagram showing the function of an Unlock mode of operation, in which the function of various light emitting diodes (LEDs) and the operation of the engine are shown;  
         [0034]      FIG. 16  illustrates a diagram showing the function of a Lock mode of operation, in which the function of various LEDs and the operation of the engine are shown;  
         [0035]      FIG. 17  illustrates a diagram showing the function of an L-mode of operation, in which the function of various LEDs and the operation of the engine are shown;  
         [0036]      FIG. 18  illustrates the control device for the watercraft including the portable unit and the main unit configured in accordance with certain features, aspects and advantages of the present invention;  
         [0037]      FIG. 19  is a flow diagram illustrating a system for storing identification data of the portable unit and for illuminating various LEDs depending on the status of the watercraft control device;  
         [0038]      FIG. 20A  is a side elevational and sectioned view of one preferred embodiment of an antenna that is configured in accordance with certain features, aspects and advantages of the present invention; and  
         [0039]      FIG. 20B  is a side elevational and sectioned view of another preferred embodiment of an antenna that is configured in accordance with certain features, aspects and advantages of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0040]     An overall configuration of an embodiment of a personal watercraft  10  is described below in connection with  FIGS. 1-4 . The watercraft  10  advantageously employs a security system  11 , which is configured in accordance with features, aspects and advantages of the present invention. The described control system configuration has particular utility for use with personal watercraft, and is described in the context of personal watercraft. The control system is not limited to use with personal watercraft, and can be applied to other types of watercraft, such as, for example, small jet boats and other vehicles.  
         [0041]     As shown in  FIG. 1 , the personal watercraft  10  is designed to travel on a body of water  13 . As such, the watercraft  10  includes a hull  14  formed with a lower hull section  16  and an upper hull section or deck  18 . The lower hull section  16  and the upper hull section  18  preferably are coupled together to define an internal cavity  20 . A bond flange  22  defines an intersection of the two hull sections  16 ,  18 .  
         [0042]     The illustrated upper hull section  18  preferably comprises a hatch cover  24 , a control mast  26 , a smaller hatch cover  27 , and a seat  28 , which are arranged generally in series from fore to aft. In the illustrated arrangement, a forward portion of the upper hull section  18  defines a bow portion  30  that slopes upwardly.  
         [0043]     A forward bulkhead  33  is formed within the hull. Preferably, a storage compartment  31  is positioned proximate the forward bulkhead  33 . In the illustrated arrangement, a lower surface  35  of the storage compartment  31  rests on a generally horizontal surface  37  of the forward bulkhead  33 . A downwardly sloping surface preferably is located rearward of the surface  37 . A lower hull cavity  39  is positioned generally beneath the forward bulkhead  33  and, more particularly, generally beneath the generally horizontal surface  37 .  
         [0044]     A maintenance opening  40  is advantageously defined through a wall of the storage compartment  31 . In one arrangement, the maintenance opening  40  is defined through a rear wall of the storage compartment. The opening  40  preferably is sufficiently large to allow maintenance of portions of the security system  11 , which is described in greater detail below. More preferably, the opening  40  is sufficiently large to allow the serviced components to be removed from the watercraft through the opening  40 .  
         [0045]     An opening is advantageously provided through the bow portion  30  so the rider can access the internal storage compartment  31 . An access lid  41  is securely attached through fasteners  43  to an upper support  45  of the storage compartment  31 . The lid  41  is designed to close the opening  40 . Preferably, the lid  41  seals or substantially seals the opening  40 . More preferably, when the lid  41  is closed, a substantially watertight seal is formed over the opening  40 . As discussed above, removal of the lid  41  allows access to a front portion of the internal cavity  20 .  
         [0046]     The hatch cover  24  is detachably affixed or hinged to the bow portion  30  to cover the opening in the hull that provides access to the storage compartment  31  or the corresponding region of the watercraft. The smaller hatch cover  27  allows access to a second, smaller storage compartment  29  that lies generally between the control mast  26  and the seat  28 .  
         [0047]     The control mast  26  extends upwardly and supports a handle bar  32  through a steering bracket  34 . The handle bar  32  is provided primarily for controlling the direction of the watercraft  10 . The handle bar  32  preferably carries other mechanisms, such as, for example, a throttle lever (not shown) that is used to control the engine output (i.e., to vary the engine speed) and a starter switch  47  that is used to initiate a starter motor  49  ( FIG. 13 ). The watercraft also advantageously comprises a power switch, which energizes the electrical systems when turned on. Furthermore, at least one buzzer and at least one light are advantageously provided so that the operator can hear the buzzer and see the light when the watercraft is ready for boarding and during operation. In some embodiments, an LED display is also used.  
         [0048]     The seat  28  extends rearwardly from a portion just rearward of the bow portion  30 . In the illustrated arrangement, the seat  28  has a saddle shape. Hence, a rider can sit on the seat  28  in a straddle fashion.  
         [0049]     Foot areas  36  are defined on both sides of the seat  28  along a portion of the top surface of the upper hull section  18 . The foot areas  36  are formed generally flat but may be inclined toward a suitable drain configuration.  
         [0050]     A fuel tank  42  is positioned in the cavity  20  under the bow portion  30  of the upper hull section  18  in the illustrated arrangement. A duct  43  preferably couples the fuel tank  42  with a fuel inlet port positioned at a top surface of the bow  30  of the upper hull section  18 . A closure cap  44  ( FIG. 2 ) closes the fuel inlet port to inhibit water infiltration.  
         [0051]     An engine  12  is disposed in an engine compartment that is defined, for example, within the cavity  20 . The engine compartment preferably is located under the seat  28 , but other locations are also possible (e.g., beneath the control mast or in the bow). In the illustrated configuration, the engine compartment is defined within the cavity  20  by the forward bulkhead  33  and a rearward bulkhead  46 .  
         [0052]     A jet pump unit  48  propels the illustrated watercraft  10 . Other types of marine drives can be used depending upon the application. The jet pump unit  48  preferably is disposed within a tunnel  50  formed on the underside of the lower hull section  16 . The tunnel  50  has a downward facing inlet port  52  opening toward the body of water. A jet pump housing  54  is disposed within a portion of the tunnel  50 . Preferably, an impeller  55  is supported within the jet pump housing  54 .  
         [0053]     An impeller shaft  56  extends forwardly from the impeller and is coupled with a crankshaft  58  of the engine  12  by a suitable coupling device  60 . The crankshaft  58  of the engine  12  thus drives the impeller shaft  56 . The rear end of the housing  54  defines a discharge nozzle  61 . A steering nozzle  62  is affixed proximate the discharge nozzle  61 . The steering nozzle  62  is pivotally movable about a generally vertical steering axis. The steering nozzle  62  is connected to the handle bar  32  by a cable or other suitable arrangement so that the rider can pivot the nozzle  62  for steering the watercraft.  
         [0054]     The engine  12  in the illustrated arrangement operates on a four-stroke cycle combustion principal. The engine  12  is an inclined L4 (in-line four cylinder) type. The illustrated engine, however, merely exemplifies one type of engine on which various aspects and features of the present invention can be used. Engines having a different number of cylinders, other cylinder arrangements, other cylinder orientations (e.g., upright cylinder banks, V-type, W-type, and opposing), and operating on other combustion principles (e.g., crankcase compression two-stroke, diesel, and rotary) are all practicable. Many orientations of the engine are also possible (e.g., with a transversely or vertically oriented crankshaft).  
         [0055]     The engine  12  preferably includes an air induction system  78  to guide air to the engine  12 . The illustrated air induction system includes an air intake box  84  for smoothing intake airflow and acting as an intake silencer. The intake box  84  in the illustrated embodiment is generally rectangular. Other shapes of the intake box of course are possible.  
         [0056]     One advantageous arrangement includes an electronic control unit  98  (ECU), such as, for example, a microcomputer. The ECU  98  preferably comprises a microcontroller having a central processing unit (CPU), a timer, and memory storage. The memory storage comprises at least an electrically erasable programmable read only