The present application is based on and claims priority to Japanese Patent Application No. 11-170731, which was filed on Jun. 17, 1999, the entire contents of which are hereby expressly incorporated by reference. The entire contents of Japanese Patent Application No. 11-75968, which was filed on Mar. 19, 1999, is also hereby expressly incorporated by reference.
1. Field of the Invention
The present invention generally relates to a control system for a personal watercraft. More particularly, the present invention relates to a emergency shut-off system for a personal watercraft.
2. Description of Related Art
As personal watercraft have become popular, they have become increasingly fast. Today, personal watercrafts are capable of speeds greater than 60 mph. To attain such speeds, personal watercrafts are driven by high power output motors.
Typically, two-cycle engines are used in personal watercraft because two-cycle engines have a fairly high power to weight ratio. One disadvantage of two-cycle engines, however, is that they produce relatively high emissions. In particular, large amounts of carbon monoxide and hydrocarbons are produced during operation of the engine. When steps are taken to reduce these emissions, other undesirable consequences typically result, such as an increase in the weight of the engine, the cost of manufacture, and/or the reduction of power.
It has been suggested that four-cycle engines replace two-cycle engines in personal watercraft. Four-cycle engines typically produce less hydrocarbon emissions than two-cycle engines while still producing a relatively high power output. However, adapting four-cycle engines for use in personal watercraft has its own engineering and technical challenges.
For example, as compared to two-cycle engines, four-cycle engines are typically more susceptible to water corrosion. Accordingly, personal watercraft with four-cycle engines typically include an emergency shut-off system that prevents water from entering the engine compartment when the personal watercraft is overturned. An example of such an emergency shut-off system is disclosed in Japanese Patent Laid Open No. 849596 (1996). This particular emergency shut-off system includes an overturn switch. The overturn switch includes a weight that sways back and forth as the personal watercraft is rocked from side to side. When the weight sways beyond a specified range, a circuit in the overturn switch is closed and the engine is shut off. Thus, the air pressure inside the engine compartment remains positive and water is less likely to be drawn into the engine compartment if the watercraft is overturned.
There, however, are several problems associated the emergency shut-off system described above. In particular, the circuit in the overturn switch can close when the watercraft is making a sharp or quick turn. That is, the weight can sway beyond the specified range during a sharp or quick turn as well as when the watercraft is overturned.
Thus, there exists a need for a improve emergency shut-off system that does not suffer significantly from these problems.
Thus, one aspect of the present invention is a method of operating an emergency shut-off system for a small watercraft is disclosed. The small watercraft comprises a hull that defines an engine compartment, an internal combustion engine supported within the engine compartment, an overturn switch, and an electronic control unit that is in electrical communication with the overturn switch. A signal from the overturn switch is sensed by the electronic control unit. The emergency shut-off system determines if the overturn switch is generating a signal for at least a preset amount of time. If the overturn switch has generated a signal for at least the preset amount of time, the engine is shut off.
Another aspect of the present invention is another method of operating an emergency shut-off system for a small watercraft. The small watercraft includes a hull that defines an engine compartment, an internal combustion engine supported within the engine compartment, a water level detection sensor positioned in the engine compartment, a bilge pump, and an electronic control unit that is in electrical communication with the sensor and the pump. The electronic control unit senses a signal from the water level detection sensor. The engine is shut off when the water level detection sensor indicates that water in the engine compartment exceeds a preset level. The bilge pump is activated.
Yet another aspect of the present invention is a small watercraft comprising a hull that defines an engine compartment, an internal combustion engine supported within the engine compartment, and an emergency shut-off system. The emergency shut-off system comprises an overturn switch and an electronic control unit that is in electrical communication with the overturn switch and the engine. The electronic control unit is configured to sense a signal generated by the overturn switch. The electronic control unit is also configured to determine if the signal generated by the overturn switch continues for a period longer than a preset amount of time. The electronic control unit is further configure to shut off the engine if the signal generated by the overturn switch continues beyond the preset amount of time.
Another aspect of the present invention is a small watercraft comprising a hull that defines an engine compartment, an internal combustion engine supported within the engine compartment, a water level detection sensor positioned in the engine compartment, a bilge pump positioned within the hull, and an electronic control unit. The electronic control unit is in electrical communication with the bilge pump and the engine. The sensor is configured to send a signal to the electronic control unit when water in the engine compartment rises above a specified level. The electronic control unit is configured to sense the signal from the water level detection sensor, to shut off the engine and to activate a bilge pump that is positioned within the engine compartment.
Another aspect of the present invention is a small watercraft comprising a hull that defines an engine compartment, an internal combustion engine supported within the engine compartment, a bilge pump positioned within the hull, and an electronic control unit in electrical communication with the bilge pump and the internal combustion engine. The watercraft also includes means for shutting off the engine when the watercraft is overturned.
The above-mentioned and other features of the invention will now be described with reference to the drawings of preferred embodiments of the present invention. The illustrated embodiments of the emergency shut-off system, which are employed in a watercraft, are intended to illustrate, but not to limit, the invention. The drawings contain the following figures:
The present invention generally relates to an improved emergency shut-off system having certain features and advantages in accordance with the present invention. The emergency shut-off system is described in conjunction with a personal watercraft because this is an application in which the system has particular utility. Accordingly, an exemplary personal watercraft 10 will first be described in general detail to assist the reader's understanding of the environment of use. Of course, those of ordinary skill in the relevant arts will readily appreciate that the emergency shut-off system described herein can also have utility in a wide variety of other settings, for example, without limitation, small jet boats and the like.
The small watercraft and a corresponding engine 12 used in the small watercraft will be described with initial reference to
With reference now to
As viewed in the direction from the bow to the stem, the deck 20 includes a bow portion 24, a control mast 26, and a rider's area 28. The bow portion 24 preferably includes a hatch cover (not shown). The hatch cover preferably is pivotally attached to the deck 20 such that it is capable of being selectively locked in a substantially closed watertight position. A storage bin (not shown) preferably is positioned beneath the hatch cover.
The control mast 26 supports a handlebar assembly 32. The handlebar assembly 32 controls the steering of the watercraft 10 in a conventional manner. The handlebar assembly 32 preferably carries a variety of controls for the watercraft 10, such as, for example, a throttle control (not shown), a start switch (not shown), and a lanyard switch (not shown). Additionally, a gauge assembly (not shown) is preferably mounted to the upper deck section 20 forward of the control mast 30. The gauge assembly can include a variety of gauges, such as, for example, a fuel gauge, a speedometer, an oil pressure gauge, a tachometer, and a battery voltage gauge.
The rider area 28 lies rearward of the control mast 26 and includes a seat assembly 36. The illustrated seat assembly 36 includes at least one seat cushion 38 that is supported by a raised pedestal 40. The raised pedestal 40 forms a portion of the upper deck 20, and has an elongated shape that extends longitudinally substantially along the center of the watercraft 10. The seat cushion 38 desirably is removably attached to a top surface of the raised pedestal 40 by one or more latching mechanisms (not shown) and covers the entire upper end of the pedestal 40 for rider and passenger comfort.
An engine access opening 42 is located in the upper surface of the illustrated pedestal 40. The access opening 42 opens into an engine compartment 44 formed within the hull 16. The seat cushion 38 normally covers and substantially seals the access opening 42 to reduce the likelihood that water will enter the engine compartment 44. When the seat cushion 38 is removed, the engine compartment 44 is accessible through the access opening 42.
With particular reference to
The interior of the hull 16 includes one or more bulkheads 58 (see
With reference again to
A forward air duct 76 extends through the upper deck portion 20. The forward air duct 76 allows atmospheric air C to enter and exit the engine compartment 44. Similarly, a rear air duct 78 extends through an upper surface of the seat pedestal 40, preferably beneath the seat cushion 38, thus also allowing atmospheric air C to enter and exit the engine compartment 44. Preferably, the rear air duct 78 terminates below the longitudinally extending dividing board 70. Air may pass through the air ducts 76, 78 in both directions (i.e., into and out of the engine compartment 44). Except for the air ducts 76, 78, the engine compartment 44 is substantially sealed so as to enclose the engine 12 of the watercraft 10 from the body of water in which the watercraft 10 is operated.
Both the forward and rear air ducts 76, 78 preferably include shut-off valves 77, 79. The shut-off valves 77, 79 can be made in a variety of ways but in the illustrated embodiment they are butterfly valves. Preferably, the shut-off valves 77, 79 are positioned in the forward and rear air ducts, 76, 78 such that they lie above the engine compartment 44. The shut-off valves 77, 79 are connected to actuators, which open and close the shut-off valves 77, 79. The purpose and function of the shut-off valves 77, 79 will be described in detail below.
The lower hull section 18 is designed such that the watercraft 10 planes or rides on a minimum surface area of the aft end of the lower hull section 18 in order to optimize the speed and handling of the watercraft 10 by reducing the wetted surface area, and therefore the drag associated with that surface area. For this purpose, as best seen in
With reference again to
In the illustrated watercraft, a jet pump unit 90 propels the watercraft 10. The jet pump unit 90 is mounted within the tunnel 88 formed on the underside of the lower hull section 18 by a plurality of bolts (not shown). An intake duct 92, defined by the hull tunnel 88, extends between the jet pump unit 90 and an inlet opening 94 that opens into a gullet 96. The duct 92 leads to an impeller housing 98.
A steering nozzle 100 is supported at the downstream end of a discharge nozzle 102 of the impeller housing 98 by a pair of vertically extending pivot pins (not shown). In an exemplary embodiment, the steering nozzle 100 has an integral lever on one side that is coupled to the handlebar assembly 32 through, for example, a bowden-wire actuator, as known in the art. In this manner, the operator of the watercraft 10 can move the steering nozzle 100 to effect directional changes of the watercraft 100.
A ride plate 104 covers a portion of the tunnel 88 behind the inlet opening 94 to enclose the jet pump unit 90 within the tunnel 88. In this manner, the lower opening of the tunnel 88 is closed to provide a planing surface for the watercraft 10. A pump chamber 106 thus is at least partially defined within the tunnel section 88 covered by the ride plate 104.
An impeller shaft 108 supports an impeller (not shown) within the impeller housing 98. The aft end of the impeller shaft 108 is suitably supported and journaled within a compression chamber of the housing 98 in a known manner. The impeller shaft 108 extends in a forward direction through the bulkhead 58. A protective casing preferably surrounds a portion of the impeller shaft 108 that lies forward of the intake gullet 96. The forward end of the impeller shaft is connected to the engine 12 via a toothed coupling 110.
The engine 12, which drives the jet pump unit 90, will now be described with initial reference to
The engine 12 comprises an engine body 112 having a cylinder head 114, a cylinder block 116 and a crankcase 118. The crankcase 118 defines a crankcase chamber 119. The cylinder block 116 preferably is formed with four generally vertically extending cylinder bores 120. The cylinder bores 120 may be formed from thin liners that are either cast or otherwise secured in place within the cylinder block 116. Alternatively, the cylinder bores 120 may be formed directly in the base material of the cylinder block 116. If a light alloy casting is employed for the cylinder block 116, such liners can be used.
As mentioned above, the illustrated engine 12 is a four cylinder engine; thus, the cylinder block 116 includes four cylinder bores 120. A piston 122 is provided within each cylinder bore 120 and is supported for reciprocal movement therein. Piston pins 124 connect the pistons 122 to respective connecting rods 126. The connecting rods 126, are journaled on the throws of a crankshaft 128. The crankshaft 128 is journaled by a plurality of bearings within the crankcase 118 to rotate about a crankshaft axis that lies generally parallel to the longitudinal axis of the watercraft 10. As will be explained in more detail below, the crankcase 118 preferably comprises an upper crankcase member 130 and a lower crankcase member 132, which are attached to each in any suitable manner.
The cylinder head 114 is provided with individual recesses which cooperate with the respective cylinder bores 120 and the heads of the pistons 122 to form combustion chambers 134. These recesses are surrounded by a lower cylinder head surface that is generally planar and that is held in sealing engagement with the cylinder block 116, or with cylinder head gaskets (not shown) interposed therebetween, in a known manner. This planar surface of the cylinder head 114 may partially override the cylinder bores 120 to provide a squish area, if desired. The cylinder head 114 may be affixed to the cylinder block 116 in any suitable manner.
Poppet-type intake valves 136 are slidably supported in the cylinder head 114 in a known manner, and have their head portions engageable with valve seats so as to control the flow of the intake charge into the combustion chambers 134 through intake passages 138 formed in the cylinder head 114. The intake valves 136 are biased toward their closed position by coil compression springs 140. The valves 136 are operated by an intake camshaft 142 which is suitably journaled in the cylinder head 114 in a known manner. The intake camshaft 142 has lobes that operate the intake valves 136 through thimble tappets.
The intake camshaft 142 is driven by the crankshaft 128 via a camshaft drive mechanism, which is partially shown in
With particular reference to
A valve cover 150 encloses the camshafts 142, 148 and is sealably engaged with an upper surface of the cylinder head 114. As such, the valve cover 150 protects the camshafts 142, 148 from foreign material and entraps any lubricants provided to the camshafts 142, 148.
A suitable ignition system is provided for igniting an air and fuel mixture that is provided to each combustion chamber 134. Spark plugs 152 (
With reference now to
With particular reference to
A lower wall 200 of each chamber 182, 184 is preferably inclined so as to converge to a chamber low point 195. A one-way valve 198 is preferably located at each low point 195. A one-way valve 198 is preferably positioned on the lower wall 200 of each chamber 182, 184 at the low point 195. In this manner, fluid within the chambers is collected at the low points 195 and drained through the valve 198. As with the low point 165 of the intake chamber 164, the low points 195 of the upstream and downstream chambers 182, 184 can be positioned at any location along the lower wall 200.
Each chamber 182, 184 of the intake silencer 180 preferably includes a dividing plate 196 located near the bottom of the chamber and adjacent the lower wall 200. The dividing plate 196 includes multiple holes. The purpose and function of the one-way valves 198 and the dividing plate 196 will be described below.
With continued reference to
An intake duct 208 connects the downstream chamber 184 of the intake silencer 180 to the intake chamber 164. Preferably, the intake duct 208 extends downwardly and rearwardly from the intake silencer 180 to the intake chamber 164. As best seen in
One of the features and advantages of the intake system 160 described above is that it prevents water from entering the engine 12. For example, when the watercraft 10 is rocked vigorously, water can get into the engine compartment 44 through the forward and rear air ducts 76, 78, or other openings in the hull 16. Once inside, the water can be drawn into the upstream chamber 182 of the intake silencer 180. Air C flows through the intake silencer 180 along a flow path from the inlet 202 through the connection pipe 190 and out the outlet 210. Since the inlet 202 and outlet 210 are preferably positioned in the upper sections 206, 214 of their respective chambers 182, 184 and the connection pipe connects the lower sections 192, 194 of the chambers 182, 184, the flowing air C must drastically change directions as it flows through the intake silencer 180. Thus, water in the air will be deposited onto the inner walls of the intake silencer 180 and separated from the air. The water collects at the bottom of the intake silencer 180 and is discharged to the through the one-way valves 198. The dividing plate 196 reduces waves in the accumulated water that may form due to vigorous rocking of the watercraft 10. This also reduces the amount of water mist that is formed from splashing waves.
If the watercraft 10 overturns, the accumulated water in the intake silencer 180 does not enter the intake duct 208 because the outlet 210 of the intake silencer 180 is located on the end wall 212 and is spaced from the top wall 213. Accordingly, the outlet 210 is positioned above the inner bottom surface of the intake silencer 180 when the watercraft 10 is overturned. Thus, at the time of the overturn, the accumulated water is less likely to flow through the outlet 210 into the intake duct 208.
The intake chamber 164 and intake pipes 162 also are arranged to prevent water from entering the engine 12. Specifically, and as mentioned above, the intake pipes 162 extend downwardly from the cylinder head 114. The intake chamber 164 is connected to the lower ends of the intake pipes 162. Air C entering the intake chamber 164 through the throttle valve 170 must change from a rearward flow direction to an upward flow direction to enter the intake pipes. Thus, water entrained in air that flows into the intake chamber 164 tends to deposit along the inner walls and settle at the bottom of the intake chamber 164. Water that may flow from the intake duct 208 into the intake chamber 164 also will collect at the bottom of the intake chamber 164. The accumulated water is discharge through the one-way valve 167 located at the bottom of the intake chamber 164.
Additionally, the inlets 166 of the intake pipes 162 preferably lie below and are spaced from the top wall 168 of the intake chamber 164. If the watercraft 10 is overturned so that the top wall 168 becomes the bottom surface of the intake chamber 164, water within the intake chamber 164 will not flow into the intake pipes 162.
Accordingly, the intake system 160 protects the engine 12 from water that may enter the engine compartment 44. Moreover, the components of the intake system 160 are generally near the bottom of the watercraft 10. This lowers the center of gravity and increases the turning ability of the watercraft 10.
The watercraft 10 also includes a fuel supply system that delivers fuel to the engine 12. The main components of the fuel supply system generally are illustrated in
As best seen in
With reference to
With reference again to
It is anticipated that a recess can be formed between the air intake box 164 and the cylinder block 116 to house the vapor separator 220 (e.g., the recess can be formed in one member or both members). Thus, the vapor separator 220 can be at least partially integrated (i.e., manufactured in a single piece) into the cylinder block and cylinder head in some arrangements. In such arrangements, however, it is preferred that the vapor separator be spaced from the cylinder body to reduce the amount of heat transferred between the cylinder bore and the vapor separator. This arrangement protects the vapor separator 220 and the lines (e.g., the low pressure fuel line 217) connected to the vapor separator 220 from splashing water that has entered the engine compartment. This is desired because the vapor separator 220 and lines connected to the vapor separator 220 are preferably made of aluminum, which can be damaged by water.
With particular reference to
The vapor separator 220 also includes an inlet port 226, a return inlet port 228, a vapor discharge port 230, and an outlet port 232. Preferably, these ports are located on an upper wall 233 of the vapor separator 220. More preferably, these ports are positioned to extend between adjacent intake pipes. In this manner, the vapor separator 220 can be more compactly arranged with the intake pipes 162. Such a construction further protects the vapor separator 220 from substantial water damage.
The outlet port 232 communicates with an outlet of the high pressure pump 223. The vapor discharge port 230 is positioned to the side of the inlet port 226 at a position proximate to the upper end of the housing 224. The vapor discharge port 230 communicates with a conduit 234 that communicates with the intake system 160 thus recirculating the vapors back into the intake air in any suitable manner.
The inlet port 226 connects to the lower pressure fuel line 217 that extends from the low pressure pump 216. A needle valve 236 operates at a lower end of the intake port 226 to regulate the amount of fuel within the fuel bowl 225. Specifically, a float 240 that is located within the fuel bowl 225 actuates the needle valve 236 in a known manner. When the fuel bowl 225 contains a low level of fuel B, the float 240 lies in a lower position and opens the needle valve 236. When the fuel bowl 225 contains a pre-selected amount of fuel B, the float 240 is disposed at a level where it causes the needle valve 236 to close.
The high pressure pump 223 draws fuel through a fuel strainer 242. The fuel strainer 242 lies generally at the bottom of the fuel bowl 225. Preferably, the high pressure pump 223 is an electric pump. The high pressure pump 223 draws fuel B from the fuel bowl 225 and pushes the fuel B through the outlet port 232 and into a high pressure fuel line 244, which is connected to a fuel rail or manifold 246 (
With reference again to
As shown in
The watercraft 10 also includes an engine exhaust system 122 that is illustrated in
As best seen in
The chamber 264 includes as protruding section 266 that opens up into an enlarged chamber 268, which is configured to attenuate the noise carried by the flow of exhaust gases, in a known manner. The expansion chamber 264 and the exhaust pipe 256 preferably include cooling passages 270 that are connected to a cooling system by a coolant pipe 272. The cooling system cools the exhaust gases, the exhaust pipe 256, and the expansion chamber 264 in a known manner.
The expansion chamber 264 communicates with a water lock 276 via a second exhaust pipe 278, as shown in
The water lock 278 transfers exhaust gases to a third exhaust pipe 280. The third exhaust pipe 280 extends upwardly, rearwardly and then downwardly to a discharge 282 formed on the hull tunnel 88. The third exhaust pipe 282 discharges the exhaust gases to the pump chamber 106, such that the passage of water through the exhaust pipe 282 into the water lock 278 is further inhibited.
The watercraft 10 also includes a dry sump-type lubrication system for lubricating various components of the engine 12. The lubrication system is referred to generally by the reference numeral 180 and is illustrated in
The lubrication system 180 includes lubricant collecting passages 286 that are formed at the bottom of the crankcase 32. The lubricant collecting passages 286 are formed by the lower crankcase member 132 and a lower cover 288 that is secured to the lower crankcase member 132. The lubricant collecting passages 286 include openings 290a-d that are provided at the bottom of each of the crankcase chambers 119a-d and that extend through the lower crankcase member 132. The openings 290a-d communicate with transverse passages 292a-d that extend to a suction port 300. The transverse passages 292a-d are formed from grooves 294a-d located on the lower surface 296 of the lower member 132 and the top surface 298 of the lower cover 288. With this arrangement, the lubricant collecting passages 286 communicate with each cylinder. Accordingly, lubricant can be removed from the four cylinders.
The suction port 300 is connected to a suction pump 302. As best seen in
With particular reference to
A transfer pump 316 is located below the lubricant tank 304 and draws lubricant from the lubricant tank 304 through a second lubricant pipe 318. Preferably, the second lubricant pipe 318 also includes a negative pressure valve 309. The transfer pump 316 is a positive displacement-type pump that is journaled to the crankshaft 128 in an arrangement similar to the suction pump 302. The transfer pump 316 delivers lubricant to lubricant galleries provided in the engine body 112 for lubricating moving parts in the engine body 112. For example, lubricant is supplied to lubricant passages formed within the crankcase 118 for lubricating the crankshaft 128. Additionally, lubricant is supplied to lubricant galleries configured to guide lubricant to the camshafts 142, 146, the valves 136, 146, and the cylinder bores 120 (see
Blow-by vapors are removed from the lubrication system 284 and released into the intake system 160 through various vapor passages. For example, as mentioned above, vapors from the lubricant tank 304 are delivered to the intake system 160 through the first vapor pipe 312. Additionally, as shown in
As such, the lubrication system 180 operates under the dry-sump lubrication principle, thus circulating lubricant through the engine 12 using a shallow lubricant pan and allowing the engine 12 to be mounted close to an inner surface of the lower hull section 18, as compared to engines employing wet sump type lubrication systems. This lowers the center of gravity of the watercraft 10. Of course, certain features, aspects and advantages of the present invention can be used in wet sump operations.
The watercraft 10 preferably includes an emergency shut-off system 400 that is illustrated schematically in
The emergency shut-off system 400 includes methods and apparatus for determining if the watercraft 10 is overturned from the signal generated by the overturn switch 402. In particular, the emergency shut-off system includes subroutines that determine when the watercraft 10 is overturned from the signal generated by the overturn switch 402. It should be noted that the ECU 154, which performs these subroutines, may be in the form of a hard wired feed back control circuit that performs the subroutines describe below. Alternatively, the ECU 154 can be constructed of a dedicated processor and memory for storing a computer program configured to perform the steps described below. Additionally, the ECU 154 can be a general purpose computer having a general purpose processor and the memory for storing a computer program for performing the steps and functions described below.
In one subroutine, the emergency shut-off system 400 is initialized, preferably when an ignition starting device (e.g., a key activated switch) is activated. Once initialized, the emergency shut-off system 400 determines if the overturn switch 402 is generating a signal. If a signal is not being generated, the emergency shutoff system 400 continues monitoring for a signal from the overturn switch 402. If a signal is being generated, the emergency shut off system 400 then determines if the signal continues for a predetermined amount of time (e.g., several seconds). If the signal does not continue for the predetermined amount of time, the emergency shut off system 400 determines that the watercraft 10 has not been overturned. In such a situation, the emergency shut-off system 400 continues monitoring for a signal from the overturn switch 402. If the signal does continue for the predetermined amount of time, the emergency shut-off system 400 determines that the watercraft 10 has overturned. The emergency shut-off system 400 then performs certain functions to prevent water from damaging the engine 12 as will be describe in more detail below.
The emergency shut-off system 400 can be arranged in several different ways to determine if the signal from the overturn switch 402 continues for the predetermined amount of time. For example, the emergency shut-off system 400 can be configured such that the signal from the overturn switch 400 must be continuos or substantially continues during the predetermined time period. In a modified arrangement, the emergency shut-off system 400 can be configured to determine if the signal from the overturn switch is merely being generated before and after the predetermined time period.
An advantage of the subroutine described above is that the emergency shut-off system 400 does not determine that the watercraft 10 is overturned if the watercraft 10 is merely turning abruptly or rocking back and forth quickly. In such situations, the pendulum 404 contacts the stoppers 406a, 406b for a short period of time. Accordingly, the signal generated by the overturn switch 402 do not continue for a time period greater than the predetermined time.
When the emergency shut off system 400 determines that the watercraft 10 is overturned, the emergency shut-off system 400 stops the engine 12. Preferably, this is accomplished by stopping the supply electricity to the spark plugs 154 or by closing the fuel injectors 246. The emergency stop system 400 also preferably closes the forward rear intake shutoff valves 77, 79 of the forward and rear intake ducts 76, 78. This further prevents water from entering the engine compartment.
As shown in
With reference now to
When water is accumulated in the engine compartment 44, the buoy 416 begins to rise in the cylindrical body 412. When the buoy 416 reaches the level of the positional detection sensor 418, the sensor 418 sends a signal through the controller 420 and to the ECU 154. When such a signal is received by the ECU 154, the emergency shut-off system 400 stops the engine 12. In addition, the emergency start system 400 preferably starts the bilge pump 408, thereby removing the water from the hull 16. The emergency shut-off system 400 preferably also prevents the engine 12 from being restarted until the water level inside the engine compartment 44 is lower than a predetermined level. It is anticipated that at least two activation levels can be incorporated such that the bilge pump can be controlled (on/off or speed) before the level that results in stopping the engine is reached.
When the watercraft 10 is overturned and the engine 12 is shut off by the emergency stop system 400, the pressure in the intake system 160 is no longer negative. Accordingly, the negative pressure valves 314 in the vapor pipes 312, 322 close when the watercraft 10 is overturned. This arrangement prevents lubricant from the lubricant tank 304 and the valve cover 150 from flowing into the intake system 160. In a modified arrangement, the negative pressure valves 314 can be electronic valves 314 that are controlled by the ECU 154. In such an arrangement, the emergency shut-off system 400 can be configured to shut the electronic control valves when the emergency shut-off system 400 determines that the watercraft 10 has overturned. Preferably, the valves are designed to be normally closed such that the valves close when power is removed.
In a similar manner, when the watercraft 10 is overturned and the engine 12 is shut off, the negative pressure valves 309 in the first and second lubricant pipes 308, 318 are closed. These valves 309 prevent the back flow of lubricant from the transfer pump 316 to the lubricant tank 304 and from the lubricant tank 304 to the suction pump 302. This arrangement allows the lubricant to be stored in the transfer pump 316 when the engine 12 is shut off. Accordingly, lubricant is quickly and smoothly delivered to the engine 12 when the engine 12 is restarted. In a modified arrangement, the negative pressure valves 309 can be electric valves 309 that are closed by the emergency shut-off system 400 when the watercraft 10 is overturned.
In a modified arrangement of the emergency stop system 400, the overturn switch 402 comprises an lubrication system pressure sensor. When the watercraft 10 is overturned, only a small amount of lubricant is discharged from the transfer pump 316. Accordingly, the lubrication pressure inside the lubrication system 284 dramatically drops. The emergency shut-off system 400 can be configured to shut off the engine 12 when such a dramatic drop in the lubrication system 284 is detected. In an additional arrangement, the overturn switch 402 comprises an engine compartment pressure sensor that detects the air pressure inside the engine compartment 44. When the watercraft 10 is overturned, air cannot enter the engine compartment 44. However, if the engine 12 is still running, the air in the engine compartment 44 is consumed and the air pressure drops. The emergency shut-off system 400 can be configured to shut off the engine 12 when such a pressure change is detected in the engine compartment.
As shown in
When the ECU 154 receives a signal from the water detection sensor 508 indicating that water is present in the intake chamber 164, intake silencer 180, and/or the exhaust pipe 256, the ECU 154 sends a control signal to the bilge pump 408 to drain the accumulated water from the intake chamber 164, intake silencer 180, and/or the exhaust pipe 256. This arrangement further ensures that water does not enter the engine 12 through the intake system 160 and/or the exhaust system 252. Preferably, the ECU 154 is also configured to drive the bilge pump 408 when the overturn switch 402 detects that the watercraft 10 has overturned or when the water level sensor 410 detects that water has accumulated inside the engine compartment 44.
As discussed above,
Preferably, in this arrangement, the carburetors 552 are inclined upwardly. The intake pipes 162, therefore, extend laterally to the left from the carburetors 552 and then extend downwardly. To connect to the intake chamber 164, the intake pipes 162 bend to the right and then extend laterally and downwardly to the intake chamber 164. The inlets 166 of the intake pipes 162 are spaced from the inner surface of the intake chamber 164. In this arrangement, water may enter the carburetor 552 will tend to flow downwardly toward the intake chamber 164 due to the downward incline of the carburetor 552.
The inclined nature of the engine 12 makes more space available for the exhaust system 252. Accordingly, the expansion chamber 264 can be made larger with a greater angle of curvature. This reduces the exhaust resistance and increases engine 12 output power. Additionally, the inclined engine 12 enables the watercraft 10 to have a lower center of gravity, thus improving stability.
As best seen in
The pumps 606, 608, 610 are trochoidal pumps. Accordingly, they include rotors 614, 616, 618 that are secured to and rotate with pump shaft 612. The rotors 614, 616, 618 are enclosed by a pump housing 620.
The pump housing 620 is comprised of an outer housing 622 that is secured to the crankcase 118. The outer housing 622 forms an outer periphery of the pump unit 600. The pump housing 620 also includes an inner housing 624 and an inner cover 626 that is secured inside the outer housing 622. A pump cover 628 is secured to the rear side 630 of the outer housing 622. The pump shaft 612 is rotatably supported in the pump cover 628 and the inner cover 626 through bearings 632 and 634.
The pump unit 600 is assembled by securing the outer housing 622 to the crank case 118 with a bolt 636. The inner housing 624 and inner cover 626 also are secured to the outer housing 622 with a bolt 638. A seal member 641 lies between the inner cover 626 and the crank case 118 and prevents substantial leakage. A bolt 642 also secures the pump cover 628 to the outer housing 622.
With continued reference to
As shown in
As indicated by the solid arrow 655, the first suction pump 606 draws lubricant from the collecting passage 650 and the first inlet passage 652 and delivers the lubricant to a first outlet passage 656. Similarly, the second suction pump 608 draws lubricant through the second inlet passage 654 and delivers it to a second outlet passage 658, as indicated by the alternate long and short dashed line 660. A third inlet passage 662 communicates with the lubricant tank 604 and the transfer pump 610. As indicated by short dashed lines 664, the transfer pump 610 delivers lubricant from the third inlet passage 662 to a third outlet passage 668, which is also defined by the pump housing 622.
The lubricant tank 604 is secured to the outer housing 622 by mounting bolts 670. The third inlet passage 662 is connected an outlet opening 672 in the lubricant tank 604. Sealing members 674 between the outer housing 622 and the lubricant tank 604 generally prevent the lubricant from leaking past the connection between the third inlet passage 662 and the outlet opening 672.
The third outlet passage 668, which is connected to the transfer pump 610 and the third inlet passage 662, communicates with an engine lubrication passage 676. As shown in
As shown in
As shown in
As shown in
With continued reference to
As best seen in
The lid 702 of the lubrication tank 604 includes a damping member 742. The damping member 742 includes an arm 744 that projects from the lid 702 and a flat plate 746 that extends vertically from the tip of the arm 744. The flat plate 746 faces a stopper surface (not shown) formed in the cylinder head cover 150 (see also
With reference to
The upper lid 750 supports the upper ends of the connection pipes 708, 710 and a press member 764 that is clamped between the lid 702. The connection pipes 708, 710 are inserted through holes 766 that are formed in the middle of the upper lid 750. Lubricant ports 768 are provided at the sides of the upper lid 750. The lubricant ports 768 guide lubricant from the connection pipes 708, 710 towards the vapor separator 706.
A dividing plate 770 is provided in the lower portion of the lubricant tank 604 for reducing waves while the watercraft 10 is running. As shown in
The lubrication system as described with reference to
Another advantage is that the lubricant tank 604 is directly mounted to the upper side of the pump unit 600. The space above the pump unit 600 can therefore be used to increase the size of the lubricant tank 604.
Still yet another advantage is that the connection pipes 708 and 710 are located inside the lubricant tank 604. This arrangement is simpler and takes up less space than an arrangement where the pipes are located outside the lubricant tank 604.
Of course, the foregoing description is that of certain features, aspects and advantages of the present invention to which various changes and modifications may be made without departing from the spirit and scope of the present invention. Moreover, a watercraft may not feature all objects and advantages discussed above to use certain features, aspects and advantages of the present invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein. The present invention, therefore, should only be defined by the appended claims.
Number | Date | Country | Kind |
---|---|---|---|
JP11-170731 | Jun 1999 | JP | national |
JP11-75968 | Mar 1999 | JP | national |
Number | Date | Country | |
---|---|---|---|
Parent | 10113869 | Mar 2002 | US |
Child | 11679771 | Feb 2007 | US |
Parent | 09596786 | Jun 2000 | US |
Child | 10113869 | Mar 2002 | US |