JPH0365493A - Power steering device for outboard motor - Google Patents

Abstract

PURPOSE:To generate the optimum assistance power conforming to navigating conditions by providing a controller which makes a power assistance device generate the optimum assistance power on the basis of signals of torque, number of engine revolutions and trim angle. CONSTITUTION:A controller 27 decides assistance power in consideration of signals not only of steering torque from a steering torque sensor 24 and the number of engine revolutions from a number of engine revolutions sensor 25 but also of trim angle from a trim angle sensor 26. The optimum assistance power can be generated in this way. In an outboard motorboat with a normal rotation propeller, for example, when the trim angle is small, the assistance power at the left steering is made larger than the same at the right steering, while when the trim angle is made larger, the assistance power at the left steering is gradually made smaller, and the assistance power at the right steering is gradually made larger so as to make nearly the same degree. In this contrivance, the steering of the outboard motorboat can be facilitated with a small steering load.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a power steering device for an outboard motor that power-assists the steering of an outboard motor, and in particular, to a power steering device that can suitably control the assist force. This invention relates to a power steering device for an outboard motor.

(Prior Art) FIG. 8 is a perspective view showing a conventional steering device for an outboard motor.

When an operator operates a steering wheel 2 installed in a driver's seat of a hull 1, a gear in a gear box 4 rotates via a steering shaft 3, and an inner cable 6 of a steering cable 5 is actuated by this gear.

The steering cable 5 has an inner cable 6 housed within an outer cable 7, and the inner cable 6 is a push-pull cable. Further, the steering cable 5 is arranged to extend from the gearbox 4 to the rear of the hull 1 to which the outboard motor is attached.

On the other hand, as shown in FIG. 2 (the outboard motor main body of the present invention is the same as the conventional example), the outboard motor 8 has an outboard motor main body 10 equipped with a drive shaft housing 9, etc., and a swivel A bracket 11 and a clamp bracket 12 are attached. The outboard motor main body 10 is horizontally rotatably supported by a swivel bracket 11 via a pilot shaft (not shown) fixed to the outboard motor main body 10. This swivel bracket 11 is connected to the clamp bracket 12 via the clamp bracket shaft 13.
is supported for vertical rotation. The outboard motor main body 10 is attached to the hull 1 by gripping the transom of the hull 1 with the clamp bracket 12 .

The outer cable 7 of the steering cable 5 shown in FIG. 8 is fixed to one end of the clamp bracket shaft 13. The clamp bracket shaft 13 has a hollow cylindrical shape, and the inner cable 6 passes through the clamp bracket shaft 13 and extends to the opposite side. A link mechanism 14 is attached to the tip of this inner cable 6. This link mechanism 14 is constructed by connecting an abbreviated-shaped drag link 15 and a steering bracket 16. A drag link 15 is fixed to the tip of the inner cable 6 of the steering cable 5, and a steering bracket 16 is fixed to the outboard motor main body 10. Therefore, by movement of the inner cable 6 of the steering cable 5, the outboard motor main body 10 is horizontally rotated and steered via the pilot shaft via the link machine #114.

However, with such a conventional steering system, which is based only on the operator's manual operation, the steering system is controlled depending on the navigation conditions of the hull 1, such as waves, wind, hull speed, trim angle of the outboard motor, and the rotational direction of the propeller. Since the steering load changes when steering the outboard motor, steering may become difficult.

Therefore, in order to eliminate this weight of steering, conventionally,
A hydraulic power steering device has been proposed that assists steering by pumping oil from a hydraulic pump. However, in this hydraulic power steering system, the power source for the hydraulic pump is dependent on the power of the outboard motor itself from the drive shaft, so the hydraulic pressure generated by the hydraulic pump depends on the rotation speed of the drive shaft (engine rotation speed). will change. For this reason, there is a possibility that the assist force may not be adjusted appropriately depending on the difference in navigation conditions.

(Problems to be Solved by the Invention) As described above, with the conventional outboard motor steering device, it becomes difficult to steer the outboard motor depending on the sailing conditions of the boat. In addition, conventional hydraulic power steering devices adjust the assist force appropriately according to the navigation conditions. ill t[I may not be able to do so.

This invention was made in consideration of the above circumstances,
It is an object of the present invention to provide a power steering device for an outboard motor that can easily and appropriately steer the outboard motor with a small steering load under any sailing conditions.

[Structure of the invention]

(Means for Solving the Problems) This invention provides a steering cable that is operatively connected to a steering wheel installed on a ship's hull,
A ring cable is connected to the outboard motor main body via a link mechanism, and the outboard motor main body is horizontally rotated and steered via the steering cable and the link mechanism by a steering load acting on the steering wheel, and The main parts of the power steering device are installed on the swivel bracket, and the power steering device includes a steering torque sensor that detects the steering load acting on the steering wheel, and an engine speed sensor that detects the engine speed of the outboard motor. , a trim angle sensor that detects a trim angle, a power assist device that is connected to the link mechanism and applies an assist force to the link mechanism, a torque signal from the torque sensor, and an engine rotation speed from the engine rotation speed sensor. a controller that generates an optimal assist force for the power assist device based on the signal and the trim angle signal from the trim angle sensor;
It is characterized by having the following.

(Operation) Therefore, according to the power steering device for an outboard motor according to the present invention, the controller 1-roller not only outputs the steering torque signal from the steering torque sensor and the engine rotation speed signal from the engine rotation speed sensor, but also performs trimming. The assist force is determined by considering the trim angle signal from the angle sensor, so
Optimal assist force can be generated.

For example, in an outboard motor with a forward-rotating propeller, when the trim angle is small, the assist force when steering to the left is made larger than when steering to the right, and as the trim angle increases, the assist force when steering to the left is gradually increased. and gradually increase the assist force when steering to the right until they are approximately the same. In this way, the optimum assist force suitable for the running conditions is generated, and the outboard motor can be easily and appropriately steered with a small steering load.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 4 shows a power assist device and the like in an embodiment of the power steering device for an outboard motor according to the present invention, and is a horizontal sectional view of FIG. 3.

In this embodiment, the same parts as those in the conventional example are designated by the same reference numerals, and the explanation thereof will be omitted.

As shown in FIG. 3, a power assist device 22 of a power steering device 21 is fixed with bolts 23 in front of the swivel bracket 11 of the outboard motor 20 (on the hull 1 side). This power steering device 21 also includes a steering torque sensor 24, an engine rotation speed sensor 25 shown in FIG. 1, a trim angle sensor 26, and a controller 2.
7th grade.

The power assist device 22 shown in FIG. 4 is configured such that a rack 33, a pinion 34, and reduction gears 35 and 36 connected to the pinion 34 are housed in a housing 37. In particular, the front end of the rack 33 is covered by a telescopic bellows case 32 fixed to a housing 37. The rack 33 extends horizontally in the width direction of the hull 1 and meshes with the pinion 34. Further, the reduction gears 35 and 36 are bevel gears, and the reduction gear 36 is fixed to the shaft of the motor 38. The axis of the motor 38 is installed horizontally in the width direction of the hull 1.

Further, an assist arm 39 is fixed to one end of the rack 33, and this assist arm 39 is attached to the drag link 15 of the link mechanism 14.

This installation situation is as shown in Figure 5.
9 and the inner cable 6, the tip of the drag link 15 is passed through the assist arm 39 and the inner cable 6, and the nut 41 is inserted through the washer 40.
Fixed by Therefore, by driving the motor 38 in FIG. 4, the pinion 3 is
4 rotates, the rack 33 moves linearly, and assist force is applied to the drag link 15 via the assist arm 39.

On the other hand, the steering torque sensor 24 is connected to the fixed bracket i.42.
It is bolted to the clamp bracket 12 by.

Furthermore, this steering torque sensor 24 is connected to the outer cable 7 of the steering cable 5 via a sensor bracket 43.

Therefore, when the operator operates the steering wheel 2 shown in FIG. 12 and the inner cable 6 of the steering cable 5 moves relative to the outer cable 7, the outer cable 7 shown in FIG. (steering load), the steering torque sensor 24 detects this steering load with a potentiometer or the like and transmits it to the controller 27 as a steering torque signal.

Further, the engine rotation speed sensor 25 shown in FIG.
Send to.

Further, the trim angle sensor 26 detects the trim angle at which the outboard motor main body 10 has slightly rotated from the vertical direction to the horizontal direction about the clamp bracket shaft 13, and outputs the trim angle signal to the controller 27. .

Now, as shown in FIG.
41DTHHODULE) The control unit 48 and the like are configured.

The calculation unit 44 receives the steering torque signal from the steering torque sensor 24 amplified by the amplification unit 45, the engine rotation speed signal from the engine rotation speed sensor 25, and the trim angle sensor 2.
Each trim angle signal from 6 is inputted, and the current value to be supplied to the motor 38 is calculated according to each of these signals. In other words,
When the steering torque is large, the current value to the motor 38 is increased, and when the engine speed is large, the current value to the motor 38 is decreased. Furthermore, when the trim angle is small, the assist force for left steering is made larger than the assist force for right steering, as shown in Figure 6, and as the trim angle increases, the assist force for left steering is gradually decreased. , gradually increases the assist force when steering to the right. FIG. 6 shows a case where the steering speed is constant.

The calculation unit 44 comprehensively judges these, calculates the current value to the motor 38, and determines the assist force.

The reason why the assist force during left and right steering is varied depending on the size of the trim angle is as follows.

Figures 7 (A) and (B) show the relationship between the steering direction and the steering force when steering at a constant speed, where (A> is the trim thickness and (B) is when the trim thickness is thick). The relationship is shown in Fig. 7 (A). In the case of a forward rotating propeller, if the trim angle is small and the user tries to steer to the left, the propeller 49 (Fig. 2)
It is necessary to increase the steering force due to the force other than hydraulic force generated by the clockwise rotation of the wheel. Therefore, when the trim angle is small, it is necessary to make the steering force when steering to the left greater than the steering force when steering to the right. On the other hand, as the trim angle increases, the steering force when steering to the left gradually decreases, and the steering force when steering to the right gradually increases, so that the left and right steering forces are approximately equal as shown in Figure 7 (B). Become. Based on the above-mentioned circumstances, the assist force during left and right steering is varied depending on the size of the trim angle.

The current value signal to the motor 38 determined by the calculation section 44 is processed by the torque control signal output circuit 47 and the PWM control section 48, and then reaches the power drive section 50, as shown in FIG. The power drive unit 50 amplifies the current value signal from the controller 27 in order to drive the motor 38 and outputs the signal to the motor 38 .

On the other hand, when a signal that cannot normally be detected due to breakage of the lead wire of each sensor 24, 25, 26 is output from each sensor 24, 25, 26, the abnormality detection unit 46 of the controller 27 detects the signal as an abnormality. It is output to the arithmetic unit 44 as . When this abnormality signal is input to the calculation section 44, a fail-safe signal is outputted from the calculation section 44 to the torque control signal output circuit 47. This torque control signal output circuit 47 reduces the current value signal of the motor 38 by half or cuts it off. In this way, controller 2
7 also executes control in the event of an abnormality.

According to the above embodiment, the controller 27 determines the current value to be supplied to the motor 38 based on the steering torque from the steering torque sensor 24 and the engine speed from the engine speed sensor 25, and also determines the current value to be supplied to the motor 38 based on the steering torque from the steering torque sensor 24 and the engine speed from the engine speed sensor 25. The current supplied to the motor 38 is adjusted depending on the magnitude of the current. For example, when the trim angle is small, the current to the motor 38 is adjusted so that the assist force when steering to the left is greater than the assist force when steering to the right. As a result, the assist force can be optimally controlled according to the navigation conditions, and the outboard motor can be easily and appropriately steered with a small steering load.

〔Effect of the invention〕

As described above, the power steering device for an outboard motor according to the present invention includes a steering torque sensor that detects the steering load acting on the steering wheel, and an engine speed sensor that detects the engine speed of the outboard motor. , a trim angle sensor that detects the trim angle, a power assist device that is connected to the link mechanism and applies an assist force to the link mechanism, a torque signal from the torque sensor, and an engine rotation speed from the engine rotation speed sensor. and a controller that generates an optimal assist force for the power assist device based on the signal and the trim angle signal from the trim angle sensor, thereby generating the optimal assist force that matches the navigation conditions. As a result, the outboard motor can be easily and appropriately steered with a small steering load.

[Brief explanation of drawings]

FIG. 1 is a block diagram mainly showing a controller in an embodiment of a power steering device for an outboard motor according to the present invention, and FIG. 2 is a side view showing an outboard motor to which FIG. 1 is applied.
3 is a perspective view mainly showing the power assist device of one embodiment, FIG. 4 is a horizontal sectional view of FIG. 3, and FIG. 5 is a V of FIG. 4.
Fig. 6 is a graph showing the relationship between the trim angle and the assist force, Fig. 7 (A) and (B) show the relationship between the steering direction and the steering force, and (A) is the trim thickness. When (B)
A graph showing the relationship when the trim is thick, and FIG. 8 is a perspective view showing a conventional power steering device for an outboard motor. 1... Hull, 2... Steering wheel, 5...
・Steering cable, 10...Outboard motor body, 14
... link device, 15... drug link, 16.
... Steering bracket, 22... Power assist device, 24... Steering torque sensor, 25... Engine rotation speed sensor, 26... Trim angle sensor, 27...
... Controller, 44... Enforcement section.

Claims (1)

[Claims] A steering cable is operatively connected to a steering wheel installed on the hull, and this steering cable is connected to the outboard motor body via a link mechanism, and the steering cable and link are connected by the steering load acting on the steering wheel. The main part of the power steering device is installed on the swivel bracket, and the main part of the power steering device is installed on the swivel bracket. a torque sensor, an engine rotation speed sensor that detects the engine rotation speed of the outboard motor, a trim angle sensor that detects the trim angle, and a power assist device that is connected to the link mechanism and applies an assist force to the link mechanism. , a controller that generates an optimal assist force for the power assist device based on a torque signal from the torque sensor, an engine speed signal from the engine speed sensor, and a trim angle signal from the trim angle sensor. A power steering device for an outboard motor characterized by: