JP2001001988A - Excessive thrust detector for outboard motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent breakage and breakdown of an outboard motor by disposing a tilt cylinder so that it may support the driving force of a propeller and fitting a detecting means for detecting oil pressure inside the tilt cylinder in an outboard motor equipped with a tilt cylinder. SOLUTION: A tilt cylinder 40 is disposed in parallel in the driving direction of a propeller 8 so as to support the driving force thereof. When the excessive thrust detector 10 is subjected to driving force, a piston 2a is pressed leftward (travelling direction) to raise oil pressure inside a chamber A, thereby generating the oil pressure whose magnitude meets that of the driving force in the chamber A. If the pressure sensor 9, with a pressure sensor 9 placed in the chamber A, is actuated by the oil pressure inside the chamber A beyond the prescribed magnitude of oil pressure meeting the excessive thrust, an alarm 13 is actuated to warn a steering person of it. An engine is controlled to prevent engine speed from increasing further if the pressure sensor 9 transmits an abnormality detection signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excess thrust detecting device for protecting an outboard motor provided with a tilt cylinder for protecting the outboard motor when excessive thrust occurs in a propeller.

[0002]

2. Description of the Related Art Conventional outboard motors that can be tilted up include, for example, Japanese Patent Application Laid-Open No. 7-69289, entitled "Trim / Tilt Apparatus for Marine Propulsion", and Japanese Patent Application Laid-Open No. 10-181689.
No. “Outboard power trim / tilt device”.
When navigating in shallow water or landing a ship, the part protruding downward from the bottom is rotated (tilted up) to avoid the propeller part from interfering with shallow obstacles or the ground. Can be protected.

[0003] However, in a ship to which these prior arts are applied, there is no means provided for detecting thrust generated on a propeller when an operation is performed that greatly deviates from specifications. The type of ship equipped with the outboard motor,
Since the size of the thrust generated on the propeller varies depending on the application (fishing boat, etc.), it is necessary to detect the size of the thrust generated on the propeller for each ship in some way to prevent the outboard motor from being damaged or malfunctioning. It was desired in preventing.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present invention detects the magnitude of thrust generated on a propeller in an outboard motor having a tilt cylinder, and prevents breakage or failure of the outboard motor before it occurs. It is an object of the present invention to provide a device for detecting an excessive thrust of an outboard motor.

[0005]

According to the present invention, there is provided an outboard motor provided with a tilt cylinder, wherein the tilt cylinder is disposed so as to support a propulsive force of a propeller, and a detecting means for detecting a hydraulic pressure in the tilt cylinder is provided. Was. The hydraulic pressure in the tilt cylinder corresponding to the magnitude of the excess thrust is measured in advance, and it can be recognized that excessive thrust has occurred in the propeller when the hydraulic pressure has exceeded a predetermined pressure. Further, a signal may be transmitted to an alarm device to issue an alarm when the hydraulic pressure reaches a predetermined pressure. Alternatively, the engine may be controlled by a signal transmitted from the detection means so that the engine speed does not increase.

[0006]

FIG. 1 is a schematic structural view of an outboard motor 100 provided with an excessive thrust detecting device 10 according to the present invention. As shown in FIG. 1, the outboard motor 100 includes a drive unit 11 including a propeller 8, a rudder unit 20, a tilt cylinder 40, and the like.

The fixed part 30 of the outboard motor 100 is fixed to the stern 50. The fixed portion 30 includes a rudder portion 20 that can rotate around a vertical axis. The rudder section 20 is rotated by a drive mechanism (not shown), and the direction of the drive section 11 (propeller 8) can be changed by turning the rudder section 20 to change the course of the boat.

As shown in FIG. 1, a support portion 7 is provided above the rudder portion 20, and the support portion 7 rotatably supports one end of a bracket 15. The other end of the bracket 15
The drive unit 11 is fixedly supported by the drive unit 11. A support 4 is provided below the rudder 20.

The tilt cylinder 40 comprises a cylinder part 1 and a rod part 2, and the rod part 2 is inserted into the cylinder part 1. As shown in FIG. 1, the left end of the cylinder portion 1 is rotatably supported by a support portion 4 of a rudder portion 20, and the right end of the rod portion 2 supports a drive portion 11 by a support portion 3.

A piston 2a is fixed to the left end of the rod portion 2. The piston 2a partitions the inside of the cylinder portion 1 into a chamber A (left) and a chamber B (right). As shown in FIG. 1, one end of a flexible pipe 5 is connected to the chamber A,
One end of a flexible pipe 6 is connected to the chamber B. The other end of the pipe 5 and the other end of the pipe 6 are connected to a hydraulic circuit (FIG. 3) provided in the outboard motor 100, and pressure oil is supplied to the chambers A and B via the pipes 5 and 6. It can be supplied.
The excess thrust detecting device 10 is constituted by the tilt cylinder 40, the pressure sensor 9, and the like.

When hydraulic oil is supplied to the chamber A via the pipe 5 by the hydraulic circuit shown in FIG. 3 so that the pressure in the chamber A becomes higher than the pressure in the chamber B, the piston 2a moves to the right in FIG. Then, the drive unit 11 rotates counterclockwise about the support unit 7 and is in a tilted up state as shown in FIG. Conversely, when pressure oil is supplied to the chamber B via the pipe 6 so that the pressure on the image side of the chamber B becomes higher than the pressure on the side of the chamber A, the piston 2a moves toward the chamber A, and the driving unit 11 The state returns to the state of FIG. 1 from the tilted-up state.

As shown in FIG. 1, the tilt cylinder 40 is arranged parallel to the propulsion direction so that the excess thrust detecting device 10 supports the thrust of the propeller 8. When a thrust is applied to the excess thrust detecting device 10, the piston 2a is pressed to the left (in the traveling direction) as viewed in FIG. 1, and the hydraulic pressure in the chamber A increases.
A hydraulic pressure having a magnitude corresponding to the magnitude of the thrust is generated in the chamber A.

A pressure sensor 9 is installed in the chamber A,
The pressure sensor 9 is preset so as to respond to a predetermined oil pressure corresponding to the excessive thrust generated in the propeller 8. When the oil pressure in the chamber A exceeds a predetermined pressure corresponding to the excessive thrust, the pressure sensor 9 is activated, and the alarm 13 is activated to notify the operator.

The pressure sensor 9 may be provided anywhere in the hydraulic circuit that communicates with the chamber A. When the oil pressure exceeds the predetermined pressure, the pressure sensor 9 transmits an abnormality detection signal to the alarm 13 via a wiring (not shown) or wirelessly. The alarm 13 emits an alarm sound so that the operator (or the occupant) can know that the propeller 8 is over-thrusted.

Here, the engine may be controlled when the pressure sensor 9 issues an abnormality detection signal so that the engine speed does not increase further. Further, the oil pressure detected by the pressure sensor 9 is displayed on a gauge to be monitored by the passenger, and when the oil pressure reaches a predetermined pressure or more, the passenger manually controls the engine so that the engine speed decreases. Is also good.

[0016]

The thrust generated in the propeller 8 may have an unexpected size. However, in the present invention, the tilt cylinder 40 is arranged so that the thrust generated in the propeller 8 is supported by the tilt cylinder 40. By detecting the oil pressure in the tilt cylinder 40 with the detecting means (pressure sensor 9), it is possible to prevent the occurrence of excessive thrust in the propeller 8 and to protect the outboard motor 100 from damage or failure. Can be.

The tilt cylinder 40 is arranged to support the thrust generated in the propeller 8, and the tilt cylinder 4
It is possible to detect the excess thrust applied to the propeller 8 by merely providing the detecting means (pressure sensor 9) for detecting the oil pressure within 0 without providing any other device.

[Brief description of the drawings]

FIG. 1 is a schematic structural view of an outboard motor provided with an excess thrust detecting device of the present invention.

FIG. 2 is a schematic structural view showing a state in which the outboard motor of FIG. 1 is tilted up.

FIG. 3 is a hydraulic circuit diagram of the outboard motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder part 2 Rod part 2a Piston 3, 4, 7 Support part 8 Propeller 9 Pressure sensor (hydraulic pressure detecting means) 10 Excessive thrust detecting device 15 Bracket 40 Tilt cylinder A chamber

Claims (1)

[Claims] 1. An outboard motor provided with a tilt cylinder, wherein the tilt cylinder is arranged to support a thrust generated on a propeller, and a detecting means for detecting a hydraulic pressure in the tilt cylinder is provided. Outboard thrust detection device.