JPH0159153B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention houses an engine in a cowling,
This invention relates to an outboard motor equipped with a tachometer that is attached to the stern of a ship.

Generally, outboard motors are used by being easily attached to small boats, and can be attached to a variety of boats having different sizes, weights, resistances, and the like. Therefore, for outboard motors, several types of propellers are prepared for the same outboard motor, and a propeller of optimal size is selected depending on the boat to which the outboard motor is installed.
This propeller selection is made based on the engine rotation speed of the outboard motor. In addition, the propeller wears out with use, and the engine rotation speed increases with use, which can cause damage to the outboard motor. Therefore, it is necessary to periodically check the engine rotation speed and replace the propeller if necessary. It won't happen. Furthermore, if the engine rotation speed of the outboard motor can be known while the ship is sailing, it becomes possible to operate the ship with economical fuel consumption.

However, since small vessels generally do not have a fixed tachometer, when selecting a propeller, the engine rotation speed is measured using a tachometer carried by service personnel in each market.
Rather than just selecting the appropriate propeller, we select the propeller in the absence of service personnel, confirm when to replace the propeller under long-term use, and detect the engine rotation speed while the ship is running to reduce fuel consumption. It was impossible to make any savings.

Conventionally, a tachometer has been placed on the dash panel of a boat and connected to the outboard engine, but in this type of boat, a connection cord must be attached and removed when the outboard motor is attached or detached. There is an unavoidable complexity.

SUMMARY OF THE INVENTION An object of the present invention is to provide an outboard motor equipped with a tachometer that can detect the rotational speed of an engine with high precision.

In order to achieve the above object, the present invention comprises a plurality of vibrating pieces having different natural frequencies, each vibrating piece having a vibrating base and an indicator formed at the tip of the vibrating base. The outboard motor is provided with a cowling in front of a cowling housing the engine, and the vibrating base of each vibrating piece is arranged substantially perpendicular to the reciprocating direction of the piston of the engine.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing the main parts of an outboard motor according to an embodiment of the present invention, FIG. 2 is a side view showing the main parts of the outboard motor and the cowling cut away,
The figure is a front view showing the tachometer provided in the outboard motor, Fig. 4 is a rear view of Fig. 3, Fig. 5 is a sectional view taken along the - line in Fig. 3, and Fig. 6 is the same tachometer. FIG. 3 is an enlarged side view showing a main part of the vibrating element of FIG.

As shown in FIGS. 1 and 2, an engine 3 is housed within a cowling 2 of an outboard motor 1, and the engine 3 is capable of driving a propulsion propeller (not shown) via a drive unit 4. As shown in FIGS. The engine 3 is of a horizontal cylinder type, and its piston 5 is movable back and forth horizontally. Here, a tachometer 7 is provided on the front surface 6 of the cowling 2, which forms a surface substantially perpendicular to the reciprocating direction of the piston 5.
is fixed. Note that the tachometer 7 can be removed from the cowling 2 if necessary.

As shown in FIGS. 3 to 5, the tachometer 7 has a base 10 fixed in a housing 8 by set screws 9, and 11 vibrating pieces 11 mounted on the base 10.
(11A to 11K) are held. Each vibrating piece 1
1 are arranged in parallel with each other, are given mutually different natural frequencies as will be described later, and are each held on a base 10 and extended toward the opening side of the housing 8. , and a display section 13 formed at the tip of the vibration base 12
have. The opening of the housing 8 is covered with a display window 14 made of transparent resin, and the display window 14 widely covers the display section 13 of each vibrating element 11 in the visual direction of the boat operator.

In addition, in the vibrating piece 11 of the tachometer 7, the vibrating piece 11A at the front left end is connected to its vibrating base 12.
is set to be the longest, and the natural frequency is set to resonate at an engine rotation speed of 4000 RPM, and the vibrating piece 11K on the front right end has its vibrating base 12 as the shortest,
Each of the remaining vibrating pieces 11B to 1 is set to a natural frequency that resonates with the engine rotation speed of 6000 RPM.
1J are formed so that their vibrating bases 12 are gradually shortened toward the right end side, and vibrating pieces 11B to 11E are
The vibrating pieces 11F are set to natural frequencies that resonate with the engine speed between 4000RPM and 5000RPM, and the vibrating pieces 11G and 11J are set to have natural frequencies that resonate with the engine speed between 5000RPM and 6000RPM. Each is set to a natural frequency that resonates with the rotation speed. Furthermore, among the vibrating pieces 11, the display portions 13 of the left group of vibrating pieces 11A to 11C are colored yellow, and the center group of vibrating pieces 11D to 11H are colored yellow.
The display sections 13 of the right group vibrating pieces 11I to 11K are colored red, and the left end vibration of the display board 8A attached to the housing 8 is colored blue. Engine rotational speeds of 4000 RPM, 5000 RPM, and 6000 RPM are displayed in the parts corresponding to the vibrating piece 11A, the center vibrating piece 11F, and the right vibrating piece 11K, respectively. As a result, when the engine 3 is driven, the engine rotation speed can be detected by visually checking the vibrating element 11 that is in a resonant state, and whether or not the engine rotation speed is within the normal use range can be detected using the above-mentioned color. It is now possible to identify them based on the difference in

Here, the tachometer 7 has legs that protrude from the housing 8 and are inserted into the inside of the cowling 2 with a seal plate 15 interposed between the housing 8 and the front surface 6 of the cowling 2. By attaching the locking washer 17 to 16, the cowling 2
It is said that it can be attached to the front surface 6 of the. When the tachometer 7 is installed in the above-mentioned state, as shown in FIG.
The display unit 13 is arranged substantially perpendicular to the reciprocating direction X of
It is arranged substantially perpendicular to the visual direction Y of the boat operator. Note that an adjustment section 18 is bent and formed at the tip of the display section 13 of each vibrating piece 11. By shortening the length of the adjustment section 18, it is possible to adjust the inertial mass of the vibrating element 11 and adjust the setting state of the natural frequency.

According to the above embodiment, since the tachometer 7 is provided in the cowling 2, the engine rotation speed can be detected at any time if necessary, and the propeller can be appropriately selected and the propeller replacement timing can be determined appropriately. In addition to being able to know the current situation, it is also possible to operate ships with economical fuel efficiency. Here, since the vibrating base 12 of each vibrating piece 11 constituting the tachometer 7 is arranged substantially perpendicular to the reciprocating direction X of the piston 5, each vibrating piece 11 is 3, and the rotational speed of the engine 3 can be accurately detected. In addition, since the display section 13 of each vibrating piece 11 is bent so as to be arranged substantially perpendicular to the visual direction Y of the operator, the vibrating piece 11
The resonance state of the engine 3 becomes reliably and easily visible, and the rotational speed of the engine 3 can be easily detected.

As described above, the present invention provides a tachometer comprising a plurality of vibrating pieces having different natural frequencies, each vibrating piece having a vibrating base and a display section formed at the tip of the vibrating base. The outboard motor is provided on the front surface of a cowling housing the engine, and the vibrating base of each of the vibrating pieces is disposed substantially perpendicular to the reciprocating direction of the piston of the engine.
Each vibrating piece can resonate accurately with engine vibrations based on the reciprocating motion of the piston, and the engine rotational speed can be detected with high precision.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing the main parts of an outboard motor according to an embodiment of the present invention, Fig. 2 is a side view showing the main parts of the outboard motor cut away, and Fig. 3 is a perspective view showing the main parts of the outboard motor. FIG. 4 is a rear view of FIG. 3, FIG. 5 is a sectional view taken along the line - in FIG. 3, and FIG. It is an enlarged side view. 1... Outboard motor, 2... Cowling, 3... Engine, 5... Piston, 6... Front, 7... Tachometer, 11 (11A to 11K)... Vibrating piece, 1
2... Vibration base, 13... Display section.

Claims (1)

[Claims] 1 Consists of multiple vibrating pieces with different natural frequencies,
Each of the outboard motors is provided with a tachometer on the front surface of a cowling housing the engine, each vibrating piece having a vibrating base and a display section formed at the tip of the vibrating base. The vibrating base of the vibrating piece is an outboard motor equipped with a tachometer that is arranged approximately perpendicular to the reciprocating direction of the piston of the engine.