Patent Grant
7182659
The present application claims priority under 35 USC 119 to Japanese Patent Application No. 2005-097906 filed on Mar. 30, 2005, the entire contents of which are hereby incorporated by reference.
1. Field of the Invention
The present invention relates to an improvement technique of an open/close valve, which is provided on an engine exhaust pipe outlet.
2. Description of Related Art
A boat that has an outlet of an exhaust pipe under water and allows the exhaust pipe to discharge exhaust gas into the water has been popularly used. To prevent water from entering an engine through the exhaust pipe when the boat is turned over, countermeasures have been proposed in, for example, Japanese Patent Application Laid-open No. 2004-98966 (see FIG. 8).
FIG. 8 in the JP 2004-98966 document is a perspective view showing one example of a valve, which is provided on the exhaust structure. The valve 60 (hereinafter referred to as an open/close valve 60) is provided in the vicinity of an exhaust outlet and is formed of a synthetic resin material. The valve 60 has a circular disc shape, wherein segment-like cuts are formed in the open/close valve such that the cut passes the center of the circular disc thus forming a plurality of triangular members 61. When the pressure in the inside of the exhaust pipe 38 is increased, a plurality of triangular members 61 is curved toward the exhaust downstream side. Therefore, the open/close valve 60 is opened in an approximately star shape thus allowing exhaust to be discharged to the outside of the boat to pass therethrough and preventing the intrusion of water from the outside of the boat. The open/close valve 60 performs the valve opening/closing operation by making use of the nature of the open/close valve 60. Specifically, the open/close valve 60 is deflected corresponding to the strength of an applied external force and restores an original state when the external force is removed.
The open/close valve 60 adopts the opening of the valve using the pressure of the exhaust gas as an operational principle thereof. Therefore, exhaust resistance is inevitably generated. When the exhaust resistance is large, the back pressure of the engine is increased thus adversely influencing the engine. When the open/close valve 60 is made easily deflectable to eliminate such an adverse influence, water is liable to easily enter the inside of the exhaust pipe.
Accordingly, there has been a demand for an open/close valve, which does not generate exhaust resistance in a usual state and makes the intrusion of water into the inside of the exhaust pipe difficult.
It is an object of the invention to provide an open/close valve, which can minimize the exhaust resistance in a usual state.
According to a first aspect of the present invention, in an exhaust device of a boat comprising a boat body that includes a hull which forms a boat bottom and a deck which covers the hull, an engine which is arranged in the inside of the boat body, an exhaust pipe which leads an exhaust gas generated by an engine to the outside of the boat body, and an open/close valve which is mounted on an outlet of the exhaust pipe, wherein the open/close valve includes a valve casing and a valve element which is housed in the valve casing in a vertically movable manner, the valve casing includes a cylindrical portion which extends vertically, a through hole which is formed in the cylindrical portion, a bottom portion which is mounted on a bottom of the cylindrical portion, and an exhaust inlet which is formed in an upper portion of the cylindrical portion, and the valve element includes a cylindrical body which is arranged along an inner surface of the cylindrical portion and has a height which allows the maintenance of the opening of the through hole, and a sealing plate which covers an upper portion of the cylindrical body and also has a size which allows the sealing plate to close the exhaust inlet, whereby when the hull is arranged below and the deck is arranged above, the exhaust gas which enters the valve casing through the exhaust inlet is discharged to the outside of the valve casing through the through hole, and when the hull is arranged above and the deck is arranged below, the sealing plate of the valve element which is moved due to an action of gravity closes the exhaust inlet.
When the hull is arranged below and the deck is arranged above, the valve element is moved to the bottom portion side of the cylindrical portion due to a deadweight of the valve element and hence, the exhaust inlet formed in the valve casing and the opening of the through hole are in communication with each other. Therefore, the exhaust gas that enters the valve casing through the exhaust inlet is smoothly discharged to the outside of the valve casing through the through hole.
When the hull is arranged above and the deck is arranged below, the valve element is moved to the exhaust inlet side which is formed on the upper portion of the cylindrical portion due to a deadweight of the valve element. Therefore, the sealing plate of the valve element closes the exhaust inlet whereby it is possible to prevent the intrusion of water from the exhaust inlet as much as possible.
According to a second aspect of the present invention, in an exhaust device of a boat comprising a boat body which includes a hull which forms a boat bottom and a deck which covers the hull, an engine which is arranged in the inside of the boat body, an exhaust pipe which leads an exhaust gas generated by an engine to the outside of the boat body, and an open/close valve which is mounted on an outlet of the exhaust pipe, wherein the open/close valve includes a valve casing and a valve element which is tiltably mounted on the valve casing, the valve casing includes a cylindrical portion which extends vertically, a through hole which is formed in a bottom of the cylindrical portion, and an exhaust inlet which is formed in an upper portion of the cylindrical portion, the valve element includes a sealing plate having a size which allows the sealing plate to close the through hole, an arm portion which extends from the sealing plate to allow the sealing plate to tilt, and a tilting support shaft which is provided on the arm portion at a position where the center of gravity of the valve element at a valve opened position and a valve closed position is offset from a horizontal line which passes a support shaft which tiltably supports the valve element, whereby when the hull is arranged below and the deck is arranged above, the exhaust gas which enters the valve casing through the exhaust inlet is discharged to the outside of the valve casing through the through hole, and when the hull is arranged above and the deck is arranged below, the sealing plate of the valve element which is tilted due to an action of gravity closes the through hole.
When the hull is arranged below and the deck is arranged above, there is no possibility that the sealing plate of the valve element closes the through hole of the valve casing. Therefore, the exhaust gas that enters the valve casing from the exhaust inlet can be discharged to the outside of the valve casing through the through hole.
When the hull is arranged above and the deck is arranged below, the sealing plate of the valve element is tilted about the tilting support shaft and closes the through hole of the valve casing. Therefore, it is possible to prevent the intrusion of water from the exhaust inlet as much as possible.
According to a third aspect of the present invention, the exhaust pipe includes a water muffler in a middle portion thereof, and discharges cooling water together with the exhaust gas from the outlet of the exhaust pipe.
According to the first aspect of the present invention, the open/close valve includes the valve casing and the valve element. Therefore, the open/close valve can be formed in a compact manner. Furthermore, the open/close valve is configured such that the valve element is moved vertically along with the inner surface of the valve casing due to an action of gravity. Therefore, when the hull is arranged below and the deck is arranged above, the exhaust inlet of the valve casing and the opening of the through hole are in communication with each other thus giving rise to an advantage that the exhaust resistance can be decreased.
According to the second aspect of the present invention, the open/close valve includes the valve casing and the valve element. Therefore, the open/close valve can be formed in a compact manner. Furthermore, the open/close valve is configured such that the valve element mounts the tiltable shaft on the arm portion of the valve element at the position where the center of gravity of the valve element is offset at the valve opening position and the valve closing position and the valve element is tiltable due to an action of the center of gravity. Therefore, when the hull is arranged below and the deck is arranged above, the exhaust inlet of the valve casing and the opening of the through hole are in communication with each other thus giving rise to an advantage that the exhaust resistance can be decreased.
According to the third aspect of the present invention, the outlet of the exhaust pipe is opened or closed due to the deadweight of the valve element. Therefore, when the hull is arranged above and the deck is arranged below, it is possible to avoid the intrusion of water from the outlet of the exhaust pipe as much as possible.
When the hull is arranged below and the deck is arranged above, the outlet of the exhaust pipe is largely opened. Therefore, even when the cooling water is discharged together with the exhaust gas, the exhaust resistance is not increased.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:
a) and 7(b) are explanatory views of the manner of operation of the open/close valve according to the invention;
a) and 10(b) are views showing the manner of operation of the construction shown in
The present invention will now be described with reference to the accompanying drawings, wherein the same or similar elements are identified by the same reference numeral. It should be noted that the drawings should be viewed in the direction of orientation of the reference numerals.
The jet pump 20 is a device that includes a pump housing 21, which extends rearwardly from an opening 11b formed in the boat bottom 11a, which constitutes the hull 11. An impeller (not shown in the drawing) is rotatably mounted in the inside of the pump housing 21. The impeller is connected to a drive shaft 23 of the engine 15.
The engine 15 drives the impeller that the jet pump 20 includes. Therefore, water sucked from the opening 11b formed in the boat bottom 11a is injected from steering nozzles 25 by way of a pump housing 21. Reference numeral 22 identifies a jet pump chamber that includes the jet pump 20.
The steering nozzles 25 are nozzles that are mounted on a rear end of the pump housing 21 in a state that the steering nozzles 25 are swingable in the lateral direction. The steering nozzles 25 are members for steering that control the steering direction of the boat 13 by swinging in the lateral direction with the manipulation of the steering handle 28.
The jet propelling boat 10 is a boat that travels on water. Supplying the fuel into the engine 15 from the fuel tank 14 drives the engine 15. A driving force of the engine 15 is transmitted to the jet pump 20 by way of the drive shaft 23. Water is sucked from the opening 11b formed in the boat bottom 11a by driving the jet pump 20. The sucked water is injected as injecting water from the steering nozzles 25 through the rear end of the pump housing 21.
The construction of an intake system provided on the engine 15 will now be described.
An outside air introducing port 31 for introducing outside air into the inside of the boat body 13 is formed in a front portion of the boat body 13. In this embodiment, the outside air introducing port 31 includes three outside air introducing ducts 32, 33 and 34.
The outside air introducing duct 32 is a member which includes a cylindrical body 32a, a boat body outside opening 32b and a boat body inside opening 32c, which are formed on both ends of the cylindrical body 32a. The boat body inside opening 32c is arranged below the boat body 13 and the boat body outside opening 32b is arranged above the boat body 13.
The outside air introducing ducts 33 and 34 are also constructed in the same manner as the outside air introducing duct 32. Specifically, the outside introducing ducts 33, 34 include cylindrical bodies 33a, 34a, the boat body outside openings 33b, 34b and the boat body inside openings 33c, 34c.
To supply air taken in through the outside air introducing ducts 32, 33, 34 into the engine 15, an air duct 35 extends to a rear side from a front side of the engine 15. An air cleaner 36 that purifies air is arranged on a rear end 35b of the air duct 35. An intake passage 41 for introducing air from which dust and dirt are removed into the engine 15 extends toward the engine 15 from an outlet 36b of the air cleaner.
In this embodiment, the boat body 13 includes the outside air introducing ducts 32, 33, 34. Therefore, it is possible to supply a sufficient amount of outside air into the inside of the boat body 13.
To explain the construction of an exhaust system provided on the engine 15, an exhaust pipe 42 which introduces exhaust gas generated by the engine 15 to the outside of the boat body 13 extends toward a rear side of the engine 15. An open/close valve 46 is mounted on an outlet of the exhaust pipe 42. A water muffler 44 is interposed in a middle portion of the exhaust pipe 42.
The engine 15 is arranged at the approximate center of the boat body 13. The outside air introducing ducts 32, 33, 34 which constitute the outside air introducing port 31 for taking the outside air from the outside of the boat body 13 is arranged front of the engine 15. With respect to the outside air introducing ducts 32, 33, 34, reference numerals 32b, 33b, 34b identify the boat outside openings, and reference numerals 32c, 33c, 34c identify the boat body inside openings. Furthermore, an air duct 35 is arranged behind the boat body inside openings 32c, 33c, 34c of the outer introducing ducts.
The air duct 35 is a member that is longitudinally arranged at a left side of the engine 15. A front opening 37 is provided on a front end 35a of the air duct 35. An air cleaner 36 is mounted on a rear end 35b of the air duct 35. An intake passage 41 is connected between an outlet 36b of the air cleaner and the engine 15.
The intake system of the engine is configured such that the outside air introducing port 31 is formed in the boat body 13 at a position in front of the engine 15 for supplying air to the front opening 37 of the air duct 35. Outside air that is introduced into the inside of the boat body 13 from the outside air introducing port 31 is supplied to the air cleaner 36 through the air duct 35. Subsequently, outside air is supplied to the engine 15 through the intake passage 41 connected to the outlet 36b of the air cleaner.
The construction of the exhaust system of the engine will now be explained.
An exhaust pipe 42 that introduces discharge gas generated by the engine 15 to the outside of the boat body 13 is provided. The exhaust pipe 42 is a member that includes a first exhaust pipe 43, a second exhaust pipe 44 and a third exhaust pipe 45. The first exhaust pipe 43, the second exhaust pipe 44 and the third exhaust pipe 45 are connected in this order in the direction that the exhaust gas flows. An open/close valve 46 is mounted on an outlet of the third exhaust pipe 45. At the same time, a first water muffler 48 is interposed between the first exhaust pipe 43 and the second exhaust pipe 44. A second water muffler 49 is interposed between the second exhaust pipe 44 and the third exhaust pipe 45.
In the exhaust device that constitutes the exhaust system, the exhaust pipe 42 that introduces the exhaust gas generated by the engine 15 to the outside of the boat body 13 is provided. The open/close valve 46 is mounted on the outlet of the exhaust pipe 42. At the same time, the water muffler 47 that includes the first water muffler 48 and the second water muffler 49 is interposed in the middle portion of the exhaust pipe 42 thus decreasing an exhaust noise of the engine 15 and leading the exhaust gas of the engine 15 to the outside of the boat body 13.
The first water muffler 48 and the second water muffler 49 are mounted on outer sides of side plates 54, 54 that form the jet pump chamber 22 using band-like mounting members (not shown in the drawing). To alleviate the vibrations of the boat body 13, a middle bottom 51 is formed on an inner side of the boat bottom 11a, and a foamed body 52 is sealed between the boat bottom 11a and the middle bottom 51.
The exhaust pipe 42 includes the water muffler 47 that includes the first water muffler 48 and the second water muffler 49 as elements thereof in a middle portion thereof. The exhaust pipe 42 discharges exhaust gas from the open/close valve 46 through an outlet 55 of the third exhaust pipe that includes an outlet of an exhaust pipe.
The connection pipe 61 that is mounted on the opening 56 of the jet pump chamber 22 from below includes a cylindrical body 62. A flange portion 63 is provided below the cylindrical body 62. A seal receiving portion 64 is formed on a lower end of the cylindrical body 62.
The flange portion 63 that is provided on the connection pipe 61 is mounted on the top plate 53 using fastening bolts 65, 65. The open/close valve 46 is mounted on the connection pipe 61 from below using open/close valve fastening bolts 66, 66.
The open/close valve 46 includes a valve casing 71 and a valve element 72 that is vertically movably housed in the valve casing 71. The valve casing 71 includes a cylindrical portion 73 that extends vertically. Through holes 74 are opened in the cylindrical portion 73. A bottom portion 75 is formed on a bottom of the cylindrical portion 73. An exhaust inlet 76 is formed on an upper portion of the cylindrical portion 73. The valve element 72 includes a cylindrical body 78 that is arranged along an inner surface 73b of the cylindrical portion 73 provided on the valve casing 71 and has a height that maintains openings of the through holes 74. A seal plate 77 covers an upper portion of the cylindrical body 78 and has a size capable of closing the exhaust inlet 76 formed in the valve casing 71.
When the hull 11 (see
a) and 7(b) are views for explaining the manner of operation of the open/close valve according to the invention. In
The valve element 72 is moved to the bottom portion 75 side provided on the valve casing 71 due to a deadweight of the valve element 72. The exhaust inlet 76 and the openings of the through holes 74 formed in the valve casing 71 are in communication with each other. Therefore, the exhaust gas that enters the valve casing from the exhaust inlet 76 is smoothly discharged to the outside of the valve casing 71 through the openings formed in the through holes 74.
In
The valve element 72 is moved to the exhaust inlet 76 side provided to the valve casing 71 due to the deadweight of the valve element 72. Therefore, the seal plate 77 of the valve element 72 closes the exhaust inlet 76 whereby the intrusion of water from the exhaust inlet 76 can be avoided as much as possible.
In this manner, the open/close valve 46 that is mounted on the outlet 55 of the exhaust pipe (see
Furthermore, the open/close valve 46 includes the valve casing 71 and the valve element 72. Therefore, the open/close valve 46 has a simple structure. Furthermore, the open/close valve 46 is configured such that the valve element 72 is movable vertically due to the action of gravity along the inner surface 73b of the cylindrical portion 73 provided on the valve casing 71. Accordingly, when the hull 11 is arranged below and the deck 12 is arranged above, the exhaust inlet 76 of the valve casing 71 and the openings of the through holes 74 are in communication with each other thus reducing the exhaust resistance.
The open/close valve 46B includes a valve casing 71B and a valve element 72B that is tiltably mounted on the valve casing 71B. The valve casing 71B includes a cylindrical portion 73B that extends vertically. A through hole 74B is formed in a bottom of the cylindrical portion 73B. A discharge inlet 76B is formed in an upper portion of the cylindrical portion 73B. The valve element 72B includes a seal plate 87 that has a size capable of closing the through hole 74B. An arm portion 88 extends from the seal plate 87 for allowing the seal plate 87 to tilt. A tilting support shaft 89 is provided at a position where the center of gravity of the valve element 72B at the valve open position and the valve close position is offset from a horizontal line through which a support shaft pivotally supporting the valve element 72B passes.
When the hull 11 (see
a) and 10(b) are views showing the manner of operation of the embodiment shown in
There is no possibility that the seal plate 87 of the valve element 72B closes the through hole 74B of the valve casing 71B. Therefore, the exhaust gas that enters the valve casing from the exhaust inlet 76B can be discharged to the outside of the valve casing 71B through the opening formed in the through hole 74B. In this manner, the opening of the through hole 74B which constitutes the exhaust pipe outlet is largely opened. Therefore, even when cooling water is discharged together with the exhaust gas, the exhaust gas resistance is not increased.
In
The seal plate 87 of the valve element 72B is tilted about the tilting support shaft 89 and closes the through hole 74B of the valve casing 71B. Therefore, the intrusion of water from the exhaust inlet 76B can be prevented as much as possible.
The open/close valve 46B includes the valve casing 71B and the valve element 72B. Therefore, the open/close valve 46B has a simple construction.
Furthermore, the valve element 72B mounts the tilting support shaft 89 on the arm portion 88 of the valve element at the position where the center of gravity of the valve element 72B at the valve opening and valve closing positions is offset thus allowing the valve element 72B to be tiltable due to the action of gravity. Therefore, when the hull 11 (see
The present invention is preferably applicable to a jet propelling boat.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2005-097906 | Mar 2005 | JP | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 4498876 | Zemlicka | Feb 1985 | A |
| 6220907 | Shimizu | Apr 2001 | B1 |
| 6773317 | Dagenais et al. | Aug 2004 | B2 |
| Number | Date | Country |
|---|---|---|
| 2004-98966 | Apr 2004 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20060223393 A1 | Oct 2006 | US |
