This application claims the benefit of priority to Japanese Patent Application No. 2016-022115 filed on Feb. 8, 2016. The entire contents of this application are hereby incorporated herein by reference.
1. Field of the Invention
The present invention relates to an outboard motor.
2. Description of the Related Art
A type of watercraft equipped with an outboard motor attached to its hull has been known (see, e.g., Published Japanese Translation of PCT International Patent Application No. 2015-504813). The hull is provided with a rear wall to divide a deck space and a motor well in which the outboard motor is disposed. The outboard motor is attached to a transom provided in the motor well, and is capable of tilting up and down. When anchoring the watercraft, the outboard motor is tilted up in order to avoid the occurrence of galvanic corrosion and the attachment of algae.
To expand the deck space, it is effective to shift the rear wall rearward by reducing the size of the motor well. However, in a construction in which the rear wall is shifted rearward, the outboard motor inevitably interferes with the rear wall when located in a tilt-up position. This imposes limitations on the reduction in size of the motor well.
Preferred embodiments of the present invention provide an outboard motor including a reduced-size motor well of a watercraft hull.
An outboard motor according to a preferred embodiment of the present invention includes an engine, a cowl, and a tilt mechanism. The cowl accommodates the engine. The tilt mechanism pivots the cowl from a tilt-down position to a tilt-up position about a horizontal tilt axis. The cowl includes a movable portion. The movable portion is moved from a normal position to a contracted position so as to shrink or reduce a contour of the cowl when the cowl is pivoted from the tilt-down position to the tilt-up position by the tilt mechanism.
According to preferred embodiments of the present invention, it is possible to provide an outboard motor such that a motor well of a watercraft hull is able to be reduced in size.
The above and other elements, features, steps, characteristics and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments with reference to the attached drawings.
A watercraft 10 according to preferred embodiments of the present invention will be explained below.
The watercraft 10 includes a hull 20 and a marine propulsion device 25.
The hull 20 includes a transom 21 and a rear wall 22. The transom 21 is located at the stern of the hull 20. The transom 21 is a portion of the hull 20 and protrudes upward from the rear end of the bottom of the hull 20. The rear wall 22 is located forward of the transom 21. The rear wall 22 is a portion of the hull 20 and protrudes upward from the rear end of a deck. The rear wall 22 may be provided with a tank to hold, for example, fish in its interior. A deck space 23 that allows the crew to board is located forward of the rear wall 22. A motor well 24 in which the outboard motor 30 is disposed is located rearward of the rear wall 22.
The marine propulsion device 25 includes a bracket 28, a PTT (power tilt and trim) device 29 and the outboard motor 30. The bracket 28 is attached to the transom 21 of the hull 20. The bracket 28 supports the outboard motor 30 such that the outboard motor 30 is able to pivot in the right-and-left direction and the up-and-down direction.
The PTT device 29 pivots the outboard motor 30 in the up-and-down direction about a tilt axis AX extending in the horizontal direction. The PTT device 29 pivots the outboard motor 30 including a cowl 1 (to be described below) from the tilt-down position (see
In the present preferred embodiment, the tilt-up position indicates a positional range in which half or more of a propeller 14 (to be described below) is located above the surface of the water. Specifically, the tilt-up position is preferably in a range within, for example, about 30 degrees forward from the maximum tilt angle, or in a range that a tilt angle α is greater than, for example, about 45 degrees. On the other hand, the tilt-down position is a range in which more than half of the propeller 14 is immersed under the surface of the water. Specifically, the tilt-down position is preferably in a range within, for example, about 20 degrees rearward from the minimum trim angle, or in a range that the tilt angle α is less than or equal to about 45 degrees. It should be noted that as shown in
In thrusting the hull 20, the PTT device 29 pivots the outboard motor 30 from the tilt-up position to the tilt-down position. When the outboard motor 30 is located in the tilt-down position, the PTT device 29 is able to suitably adjust the tilt angle α of the outboard motor 30.
When anchoring the hull 20, the PTT device 29 pivots the outboard motor 30 from the tilt-down position to the tilt-up position. Accordingly, it is possible to prevent the occurrence of galvanic corrosion of the outboard motor 30 and the attachment of algae to the outboard motor 30.
The outboard motor 30 is disposed in the motor well 24. The outboard motor 30 includes the cowl 1, an upper casing 2, a lower casing 3, a bottom cowl 4 and an engine unit 5. The cowl 1, the upper casing 2, the lower casing 3 and the bottom cowl 4 define a housing of the outboard motor 30. The cowl 1, the upper casing 2 and the engine unit 5 are attached to an exhaust guide 4a disposed in the interior of the bottom cowl 4.
The cowl 1 is located above the bottom cowl 4. The cowl 1 includes a stationary portion 1a, a movable portion 1b and an opening 1c.
The stationary portion 1a is disposed on and fixed to the bottom cowl 4. The stationary portion 1a covers the engine unit 5 from lateral sides of the engine unit 5.
The movable portion 1b is disposed on the stationary portion 1a. The movable portion 1b covers the stationary portion 1a from above. The movable portion 1b is movable relative to the stationary portion 1a. When the cowl 1 is pivoted from the tilt-down position to the tilt-up position, the movable portion 1b is moved from a normal position (see
When the cowl 1 is located in the tilt-up position, the movable portion 1b is located at the forward end of the cowl 1. When the cowl 1 is located in the tilt-up position, the movable portion 1b faces the rear wall 22. The movable portion 1b is the most forward portion of the cowl 1 when the cowl 1 is tilted up. The movable portion 1b is also located closest to the rear wall 22 when the cowl 1 is tilted up. When the cowl 1 is located in the tilt-down position, the contracted position of the movable portion 1b is located below the normal position of the movable portion 1b in the vertical direction. The movable portion 1b includes air inlets 1d in both lateral portions in order to take in outside air.
The opening 1c is located on the rear end of the cowl 1. The opening 1c opens rearward. The opening 1c is a gap between the upper portion of the rear end of the stationary portion 1a and the lower portion of the rear end of the movable portion 1b. As shown in
The upper casing 2 is located below the bottom cowl 4. The lower casing 3 is located below the upper casing 2.
The engine unit 5 is disposed in the interior of the cowl 1. The engine unit 5 includes an engine 5a, a throttle body 5b, a crankshaft 5c and an ECU (electric control unit) 5d. The engine 5a is preferably an internal combustion engine that burns fuel to generate a driving force. The throttle body 5b takes in air from outside and supplies the taken-in air to the engine 5a. The crankshaft 5c extends in the vertical direction. The ECU 5d is configured or programmed to control the PTT device 29. When a vessel operator presses a tilt-down button (not shown in the drawings) and simultaneously a predetermined condition is satisfied, the ECU 5d is configured or programmed to control and cause the PTT device 29 to pivot the outboard motor 30 from the tilt-up position to the tilt-down position. When the vessel operator presses a tilt-up button (not shown in the drawings) and simultaneously a predetermined condition is satisfied, the ECU 5d is configured or programmed to control and cause the PTT device 29 to pivot the outboard motor 30 from the tilt-down position to the tilt-up position. Controlling the PTT device 29 by the ECU 5d will be described below.
As shown in
The drive shaft 11 extends in the vertical direction in the interiors of the upper casing 2 and the lower casing 3. The upper end of the drive shaft 11 is coupled to the lower end of the crankshaft 5c. The lower end of the drive shaft 11 is coupled to the front end of the propeller shaft 13 through the bevel gear 12. The propeller shaft 13 extends in the front-and-rear direction in the interior of the lower casing 3. The rear end of the propeller shaft 13 protrudes from the lower casing 3 and is coupled to the propeller 14. The propeller 14 is rotated together with the propeller shaft 13.
Next, an internal structure of the cowl 1 will be explained.
The outboard motor 30 includes an engine cover 6 disposed in the interior of the cowl 1. The engine cover 6 is connected to the upper end of the stationary portion 1a and defines a portion of the cowl 1. The engine cover 6 covers the engine unit 5 from above.
An intake pathway 7 is provided between the engine cover 6 and the movable portion 1b in order to supply air to the engine 5a therethrough. The engine cover 6 includes an intake port 6a that opens in the intake pathway 7. The outside air, flowing into the intake pathway 7 through the pair of the air inlets 1d (see
The outboard motor 30 includes an actuator 8 disposed inside the cowl 1. The actuator 8 is preferably located rearward of the engine 5a. The actuator 8 is preferably disposed in a gap between the stationary portion 1a and the engine 5a. The actuator 8 includes a body 8a and a driven portion 8b. The body 8a is fixed to a rear plate if that covers the engine 5a from behind. The body 8a is electrically connected to the ECU 5d. The lower end of the driven portion 8b is coupled to the body 8a. The upper end of the driven portion 8b is inserted through the engine cover 6, and is coupled to the rear end of the movable portion 1b by, for example, a bolt 1g. The driven portion 8b extends and contracts along the vertical direction. When the cowl 1 is pivoted from the tilt-down position to the tilt-up position, the actuator 8 contracts the driven portion 8b such that the movable portion 1b is moved from the normal position to the contracted position. When the cowl 1 is pivoted from the tilt-up position to the tilt-down position, the actuator 8 extends the driven portion 8b such that the movable portion 1b is moved from the contracted position to the normal position.
The ECU 5d is configured or programmed to control the actuator 8. When the vessel operator presses the tilt-up button and simultaneously a predetermined condition is satisfied, the ECU 5d is configured or programmed to contract the actuator 8 such that the movable portion 1b is moved from the normal position (see
The movable portion 1b pivots downward about a pivot axis 1e when moving from the normal position to the contracted position. At this time, the movable portion 1b approaches the engine cover 6. Therefore, the movable portion 1b is located closer to the engine cover 6 when in the contracted position than when in the normal position. The movable portion 1b pivots upward about the pivot axis 1e when moving from the contracted position to the normal position. The pivot axis 1e is located forward of the opening 1c. The pivot axis 1e is mounted to the front end of the movable portion 1b. The pivot axis 1e extends in the horizontal direction.
The tilt signal obtainer 51 obtains a tilt-down command signal and a tilt-up command signal. The tilt-down command signal is outputted in response to pressing the tilt-down button by the vessel operator, whereas the tilt-up command signal is outputted in response to pressing the tilt-up button by the vessel operator. The tilt signal obtainer 51 outputs either the tilt-down command signal or the tilt-up command signal to the PTT controller 53.
The tilt restrictor 52 allows or prevents pivoting of the cowl 1. The tilt restrictor 52 allows pivot of the cowl 1 from the tilt-down position to the tilt-up position when the cowl 1 is located in the tilt-down position (see
The PTT controller 53 is configured or programmed to control and cause the PTT device 29 to pivot the cowl 1 from the tilt-up position to the tilt-down position when the tilt-down command signal has been inputted to the PTT controller 53 from the tilt signal obtainer 51. The PTT controller 53 is configured or programmed to control and cause the PTT device 29 to pivot the cowl 1 from the tilt-down position to the tilt-up position when the tilt-up command signal has been inputted to the PTT controller 53 from the tilt signal obtainer 51 and simultaneously the tilt restrictor 52 has informed the PTT controller 53 to allow pivoting of the cowl 1. The PTT controller 53 is configured or programmed not to control the PTT device 29 when the tilt-up command signal has been inputted into the PTT controller 53 from the tilt signal obtainer 51 and simultaneously the tilt restrictor 52 has informed the PTT controller 53 to prevent pivoting of the cowl 1.
The movement restrictor 54 allows or prevents movement of the movable portion 1b in accordance with the pivot state of the cowl 1 being allowed or prevented by the tilt restrictor 52. The movement restrictor 54 prevents movement of the movable portion 1b from the normal position (see
The actuator controller 55 is configured or programmed to control and cause the actuator 8 to move the movable portion 1b from the contracted position to the normal position when the tilt-down command signal has been inputted to the actuator controller 55 from the tilt signal obtainer 51. The actuator controller 55 is configured or programmed to control and cause the actuator 8 to move the movable portion 1b from the normal position to the contracted position when the tilt-up command signal has been inputted to the actuator controller 55 from the tilt signal obtainer 51 and simultaneously the movement restrictor 54 has informed the actuator controller 55 to allow movement of the movable portion 1b. The actuator controller 55 is configured or programmed not to control the actuator 8 when the tilt-up command signal has been inputted to the actuator controller 55 from the tilt signal obtainer 51 and simultaneously the movement restrictor 54 has informed the actuator controller 5 to prevent movement of the movable portion 1b.
Preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above preferred embodiments, and a variety of changes can be made without departing from the scope of the present invention.
In the above preferred embodiments, the outboard motor 30 preferably includes the actuator 8 to move the movable portion 1b. However, the outboard motor 30 may not include the actuator 8. This is able to be achieved when the movable portion 1b is manually movable from the normal position to the contracted position.
In the above preferred embodiments, the actuator 8 is preferably located rearward of the engine 5a. However, the positional arrangement of the actuator 8 is not limited to this. As shown in
In the above preferred embodiments, the upper end of the driven portion 8b of the actuator 8 is preferably coupled to the movable portion 1b of the cowl 1 by the bolt 1g. However, the coupling of the upper end of the driven portion 8b to the movable portion 1b is not limited to this. The upper end of the driven portion 8b of the actuator 8 may be coupled to the movable portion 1b through a joint that is easily attachable thereto and detachable therefrom. Alternatively, the upper end of the driven portion 8b may only make contact with the movable portion 1b. These structures enable smooth attachment/detachment of the movable portion 1b of the cowl 1.
In the above preferred embodiments, the driven portion 8b of the actuator 8 is preferably coupled to the body 8a. However, the driven portion 8b may be attached to the body 8a so as to be easily detachable therefrom. This structure enables smooth attachment/detachment of the movable portion 1b of the cowl 1.
In the above preferred embodiments, the driven portion 8b of the actuator 8 is preferably directly coupled to the movable portion 1b. However, the coupling of the actuator 8 to the movable portion 1b is not limited to this. As shown in
In the above preferred embodiments, the movable portion 1b of the cowl 1 is preferably able to pivot up and down about the pivot axis 1e. However, as shown in
In the above preferred embodiments, the driven portion 8b of the actuator 8 is preferably directly coupled to the movable portion 1b. However, as shown in
In the above preferred embodiments, the outboard motor 30 preferably includes the engine cover 6. However, the outboard motor 30 may not include the engine cover 6.
In the above preferred embodiments, the movable portion 1b is preferably movable to shrink or reduce the contour of the cowl 1. However, not only the movable portion 1b but also the stationary portion 1a may be moved to shrink or reduce the contour of the cowl 1. Alternatively, only the stationary portion 1a may be moved to shrink or reduce the contour of the cowl 1. In this structure, the stationary portion 1a is an example of a “first cowl portion”, whereas the movable portion 1b is an example of a “second cowl portion”.
In the above preferred embodiments, when the cowl 1 is pivoted from the tilt-down position to the tilt-up position, the movable portion 1b is preferably moved from the normal position to the contracted position so as to reduce the contour of the cowl 1. However, the structure to move the movable portion 1b is not limited to this. Regardless of whether or not the cowl 1 is pivoted from the tilt-down position to the tilt-up position, the movable portion 1b may be movable from the normal position to the contracted position so as to reduce the contour of the cowl 1. In this configuration, the height of the outboard motor 30 is reduced by reducing the contour of the cowl 1, and thus, rear visibility is ensured. Additionally, the power performance of the engine 5a is able to be regulated by changing the contour of the cowl 1.
While preferred embodiments of the present invention have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the present invention. The scope of the present invention, therefore, is to be determined solely by the following claims.
Number | Date | Country | Kind |
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2016-022115 | Feb 2016 | JP | national |