JPS6323960B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an outboard motor that includes an engine for rotationally driving a propulsion propeller housed in a cowling and is attached to the stern of a ship.

Generally, an outboard motor is a propulsion device that can be easily attached to a small boat, and is used by being attached to a variety of boats having different sizes, weights, resistances, etc. For this reason, several types of propellers are prepared for the same outboard motor, and the propeller is selected to maximize the performance of the outboard motor for each boat. . This propeller selection is made based on the engine rotation speed of the outboard motor. Additionally, even if the propeller is properly selected to match the boat's specifications, if the propeller wears out after long periods of use, the engine rotational speed will increase beyond the original setting, potentially damaging the outboard motor. For,
The engine rotation speed must be checked periodically and the propeller replaced if necessary. moreover,
It is necessary to know the engine rotation speed in order to make appropriate engine adjustments during periodic inspections, etc., and with the current strong demand for reduced fuel consumption, it is important to operate with economical fuel efficiency. By knowing the engine speed of the outboard motor, it is possible to operate with economical fuel efficiency.

In this way, it is extremely important to check the engine rotation speed of outboard motors, so it is recommended to place a tachometer on the dash panel in the cockpit and connect it to the outboard engine, just like in a vehicle. Ta. However, with this type of vessel, there are complications such as having to always disconnect the connection cord when attaching and detaching the outboard motor from the stern.
In addition, ships equipped with outboard motor tachometers are not common because there is no space for a tachometer on normal small ships. For this reason, when selecting a propeller or regularly inspecting an outboard motor, service personnel in each market usually bring a portable tachometer to measure the engine rotational speed of the outboard motor and select the appropriate propeller. However, even this is difficult in remote locations or locations where service personnel are not available, and it is even more difficult for the user to check the engine speed of the outboard motor to confirm when to replace the propeller, or to adjust the engine. It has been impossible to operate the outboard with economical fuel consumption by knowing the engine speed of the outboard motor during operation.

On the other hand, it is conceivable to attach the rotation speed indicator directly to the engine, but in the case of an outboard engine that is housed in a cowling for protection and waterproofing, the rotation speed indicator may be visually checked during operation. Therefore, it is not possible to adjust the engine speed during operation to obtain economical fuel efficiency, and the cowling must be removed to confirm the propeller change time, which is a hassle. Ta.

The present invention has been made to address these various problems, and its gist is that in this type of outboard motor, a rotational speed indicator is directly attached to the engine, and a rotational speed indicator is mounted directly on the engine, and a rotational speed indicator is mounted directly on the engine, and a rotational speed indicator is mounted directly on the engine, and A liquid-tight opening is provided at an easily visible position, and the tachometer is made visible from the outside through the opening.

Embodiments of the present invention will be described below. FIG. 2 shows a first embodiment of an outboard motor according to the present invention. The outboard motor 10 has an engine 11 that rotationally drives a propulsion propeller (not shown) housed in a cowling 3C, and can be steered by operating a manual handle 13.

As shown in FIG. 2, the cowling 30 is composed of a bottom cowling 31 and a top cowling 32. The bottom cowling 31 is fixed to the engine 11, and a protrusion 31a is integrally formed on the hull side (the left side in FIG. 2). On the opposite side, a handle 35 to which a rotating claw 36 is fixed is rotatably attached via a shaft portion 35a. top cowling 3
2 has a hook 38 on the hull side and the opposite side of its lower edge.
and the receiving metal fitting 39 are fixed, the hooking metal fitting 38 is locked to the protrusion 31a to cover the engine 11, and the handle 35 is fixed.
The bottom cowling 31 is removably attached to the bottom cowling 31 by rotating the rotating pawl 36 and engaging the receiving metal fitting 39.

Therefore, the front surface 32b of the top cowling 32
is provided with an opening 321, and one end (on the lid body 22 side, which will be described later) of the synchronized vibration type rotational speed indicator 20 fixed to the hull side end of the engine 11 is provided with an opening 321.
1 and exposed to the hull side, the seal member 32
2, it is liquid-tightly sealed. As shown in FIGS. 2 and 3, this rotational speed indicator 20 consists of a resin box 2 with a U-shaped cross section and an open end.
1, a transparent resin lid 22 having a U-shaped cross section and fitted onto one end of the box 21 to cover the opening thereof;
Eleven vibrating pieces 24a to 24 are fixed to and protrude from the tip of the vibrating table 23 fixed to the inner bottom of the box body 21.
It is composed of k. Each vibrating piece 24a-2
4k consists of a vibration base 241 that projects horizontally and a vibration display section 242 that is bent at the tip of the vibration base 241 and projects downward. The vibrating base 241 of the rightmost vibrating piece 24k is formed to be the longest, and the vibrating base 241 of the remaining vibrating pieces 24b to 24j is formed to be gradually shorter toward the right end. As a result, the natural frequencies of the vibrating pieces 24a to 24j are different from each other,
When the frequency caused by the drive of the engine 11 matches the natural frequency of any one of the vibrating pieces 24a to 24k, resonance occurs in the vibrating piece and the vibration display section 242 vibrates up and down with a large amplitude. Further, among the vibrating pieces 24a to 24k, the natural frequency of the left end moving piece 24a is determined by, for example, the engine rotation speed.
The vibration frequency of the engine 11 that occurs at 4000 RPM,
The central vibrating piece 24f is
The frequency of engine 11 generated at 5000 RPM,
The natural frequency of the right-end vibrating piece 24k is set to the frequency of the engine 11 that occurs when the engine rotational speed is 6000 RPM. In addition, each vibrating piece 24
The natural frequencies of b to 24e are determined by the engine rotation speed.
The natural frequencies of the vibrating pieces 24g to 24j are set to predetermined frequencies that occur between 4000 RPM and 5000 RPM, and the natural frequencies of the vibrating pieces 24g to 24j are set to predetermined frequencies that occur when the engine rotational speed is between 5000 RPM and 6000 RPM. On the other hand, among the vibrating pieces 24a to 24k, the vibration display section 242 of the left group of vibrating pieces 24a to 24c
The vibration display portions 242 of the vibrating pieces 24d to 24h in the center group and the vibration display portions 242 of the vibrating pieces 24i to 24k in the right group are colored yellow, blue, and red, for example, as shown in FIG. The lid body 22
Engine rotational speeds are displayed at locations corresponding to the left end vibrating piece 24a, the center vibrating piece 24f, and the right end vibrating piece 24k. As a result, the engine 11
The engine rotation speed can be known by checking the vibrating element that is in a vibrating state when the engine is being driven, and it is also possible to distinguish by color whether the engine rotation speed is within the normal rotation speed range.

The rotational speed indicator 20 is arranged so that its lid body 22 faces the hull side, and is fixed to the hull side of the engine 11 with a mounting bolt 25 via a spring washer.

In this way, in the outboard motor 10, the lid 22 side of the rotational speed indicator 20 passes through the opening 321 of the top cowling 32 and is exposed to the hull side, so even during operation, the engine rotation can be adjusted at any time. By being able to visually check the speed, you can not only select a propeller appropriately, but also know when to replace the propeller, and operate a vessel equipped with an outboard motor 10 with economical fuel efficiency. It becomes possible to do so. In addition, since the rotational speed indicator 20 is fixed to the engine 11, it can be used not only when the top cowling 32 is attached but also when the engine 11
Even when the top cowling 32 is removed for adjustment, the rotational speed of the engine can be visually checked, allowing more reliable engine adjustment. Furthermore, when attaching and detaching the top cowling 32 and detaching the outboard motor 10 from the stern, there is no need for any complicated work such as detaching the connection cord.

FIG. 5 shows a part of an outboard motor according to a second embodiment of the present invention. Even with this outboard motor,
A synchronized vibration type rotational speed indicator 20 of the same type as that used in the outboard motor 10 of the first embodiment is attached to the engine 11.
is fixed directly to the That is, the rotational speed indicator 20 has a pair of brackets 211, 211 integrally formed on the left and right sides of a box body 21, and these brackets 211, 211 are attached to mounting bolts 25,
25 is attached and fixed to the upper surface of the engine 11 on the side of the hull. On the other hand, top cowling 32
A recess R is formed in the upper surface 32a, and a flat plate 323 made of transparent resin is liquid-tightly fixed to the upper opening of the recess R. Further, one end (lid side 22) of the rotational speed indicator 20 faces the opening 324 provided in the inner wall of the recess R, and each rotational speed indicator 20 is viewed from the hull side through the flat plate 323. The vibrating pieces 24a to 24k are made visible.

In each of the above embodiments, a synchronized vibration type rotation speed indicator 20 is used as the rotation speed indicator, but a normal engine rotation speed indicator such as a tachometer may also be used. .

As explained above, in the present invention, in an outboard motor which is installed at the stern of a boat body and has an engine for rotationally driving a propulsion propeller housed in a cowling, a rotation speed indicator is directly attached to the engine, and a rotation speed indicator is directly attached to the engine. The structure is characterized in that a liquid-tight opening is provided in the cowling at a position that is easily visible from the hull side, and the rotational speed indicator is made visible from the outside through the opening. Therefore, according to the present invention, it is possible to know the engine speed at any time both when the cowling is attached and when it is removed, and thereby, it is possible to appropriately select a propeller and also to determine the timing for replacing the propeller appropriately. You can know for sure, and you can also operate a boat equipped with an outboard motor with economical fuel consumption.
Moreover, even when the cowling is removed, the engine can be adjusted more accurately while looking at the rotational speed indicator.

[Brief explanation of drawings]

FIG. 1 is a partial perspective view of an outboard motor to which the present invention is applied, FIG. 2 is an enlarged vertical sectional view showing a first embodiment of the present invention, and FIG. 3 is a cross-sectional plan view of a rotation speed indicator. FIG. 4 is a front view of FIG. 3, and FIG. 5 is an enlarged longitudinal cross-sectional view showing essential parts of a second embodiment of the present invention. Explanation of symbols, 10... Outboard motor, 11... Engine, 13... Manual handle, 20... Rotation speed indicator, 21... Box body, 22... Lid body, 24a
~24k... Vibration piece, 30... Cowling, 32
1,324...Aperture.

Claims (1)

[Claims] 1. In an outboard motor that is installed at the stern of a boat and has an engine that rotationally drives a propulsion propeller housed in a cowling, a rotation speed indicator is directly attached to the engine and placed in a position where it can be easily seen from the hull side of the cowling. An outboard motor equipped with an engine rotational speed indicator, characterized in that an opening is provided with a liquid-tight structure, and the rotational speed indicator is visible from the outside through the opening.