JPH0710677B2 - Hydraulic tilt device for outboard motors - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a tilt-up device for elevating an outboard propulsion device such as a drive unit for an outboard motor or an outboard motor between water and water, and more particularly, This relates to a device that absorbs the impact of an outboard propulsion unit when it collides with driftwood or other suspended matter during normal navigation.

[Conventional technology and its problems]

2. Description of the Related Art Conventionally, in a hydraulic tilt device, a piston of a tilt cylinder is provided with two reciprocating oil passages having check valves in different forward directions, and when an outboard propulsion device collides with a floating object, it is outboarded. There is a mechanism that allows the propulsion device to quickly escape to the rear and then slowly return by gravity. However, it is not easy to set the size of the oil passage that penetrates the front and back of the piston. That is, when the oil passage diameter is too small, the outboard propulsion machine cannot be escaped and it is damaged.On the contrary, when the oil passage is too large, the piston of the tilt cylinder instantaneously moves through the entire stroke to end the stroke. It may collide with and damage it.

[Outline of Object and Structure of Invention]

It is an object of the present invention to obtain a device which does not have the above-mentioned problems and which allows the outboard propulsion device to quickly escape rearward in the event of a collision with a floating substance, and in which the tilt piston does not move all the way to the stroke end. , By the piston in the hydraulic cylinder of the tilt cylinder that raises and lowers the outboard propulsion unit 2
Among the oil chambers defined in the chamber, the oil chamber through which the piston rod penetrates is communicated with the oil passage through which the hydraulic oil is pumped when the outboard propulsion device in the hydraulic oil supply device is lowered into the water, and the hydraulic pressure An oil chamber opposite to the oil chamber with respect to the piston in the cylinder is communicated with an oil passage through which hydraulic oil is pressure-fed when the outboard propulsion device in the hydraulic oil supply device is pulled above water, and the piston is connected to the piston. , When the piston moves to the cylinder extension side, and when the piston moves to the cylinder shortening side and the first oil passage having a check valve through which hydraulic oil flows when a pressure above a certain level is applied. And a second oil passage having a check valve through which hydraulic oil flows when a pressure above a certain level is applied to each of the two pressure receiving surfaces of the piston so as to penetrate the piston. Between the end of the piston rod penetrates the cylinder, the piston is characterized in that provided a throttle means for throttling the cross-sectional area of the first oil path immediately before reaching the stroke end of the cylinder extension side.

[Action]

When a large floating matter on the water collides with the outboard propulsion device, a force to extend it is applied to the tilt cylinder, and the hydraulic oil passes through the first oil passage of the piston, so that the piston moves quickly to the cylinder extension side. . Therefore, the outboard propulsion device retracts above the water while extending the tilt cylinder to avoid floating objects. At this time, when the piston abruptly approaches the stroke end on the cylinder extension side, the throttle means throttles the cross-sectional area of the first oil passage to restrict passage of the working oil, so that the piston penetrates the piston rod of the hydraulic cylinder. Before it hits the end, it stops or decelerates rapidly.

After avoiding floating matter, the tilt cylinder receives a force to compress it due to the weight of the outboard propulsion unit, so that the hydraulic oil passes through the second oil passage of the piston and the piston moves toward the cylinder shortening side. It slowly moves and the outboard propulsion unit returns to the normal running state.

On the other hand, when the outboard propulsion device is pulled up to the water, the hydraulic oil supply device pumps the hydraulic oil to the oil chamber on the side opposite to the oil chamber through which the piston rod of the tilt cylinder penetrates. When lowering the hydraulic oil, the hydraulic oil supply device pumps the hydraulic oil into the oil chamber through which the piston rod of the tilt cylinder penetrates. When hydraulic oil is pumped to the oil chamber on the opposite side of the oil chamber through which the piston rod penetrates, the piston moves to the cylinder extension side of the hydraulic cylinder, the piston rod projects from the hydraulic cylinder, and the outboard propulsion device is pulled up. To be When the hydraulic oil is pumped to the oil chamber through which the piston rod penetrates, the piston moves to the cylinder shortening side of the hydraulic cylinder, the piston rod is inserted into the hydraulic cylinder, and the outboard propulsion unit is lowered.

〔Example〕

The present invention will be described below with reference to the illustrated embodiment. In the drawing, an outboard motor, which is an outboard propulsion device 3, is supported by a pin 4 on a bracket 2 provided at the stern of a hull 1, and the Move up and down in water. Reference numeral 5 is a tilt cylinder that connects the two, and is composed of a hydraulic cylinder 5a and a piston 7 in which a piston rod 6 (hereinafter simply referred to as rod 6) is provided so as to project into the hydraulic cylinder. The hydraulic cylinder 5a is connected to the outboard propulsion unit 3. Further, the rod 6 is rotatably connected to the bracket 2, respectively.

The interior of the hydraulic cylinder 5a is partitioned by the piston 7 into a lower chamber 5b located on the rod 6 side and an upper chamber 5c on the rear surface thereof.
b and 5c are connected to two ports 8a and 8b of the rotary pump 8 via a first oil passage 9a and a second oil passage 9b, respectively.
The pump 8, the first oil passage 9a, and the second oil passage 9b constitute a hydraulic oil supply device. The discharge port and the suction port of the pump 8 are changed by changing the rotation direction. When the pump 8 rotates normally, the port 8a serves as the discharge port, and the port 8b serves as the suction port. Port 8a serves as an inlet. Reference numeral 8c is an oil supply port of the pump 8 connected to the tank 81, and replenishes the pump 8 with hydraulic oil.

Reference numeral 12 is a trim cylinder installed on the bracket 2 for adjusting the mounting angle of the main body 3 of the outboard motor with respect to the hull 1. The trim cylinder 12 is composed of a hydraulic cylinder 12a, a piston 12b fitted to the hydraulic cylinder 12a, and a rod 12c protrudingly provided on one side thereof. The rod 12c supports the front side of the outboard propulsion unit 3 and transmits thrust to the outboard. 12d is a lower chamber formed on one side of the piston 12b, and 12e is an upper chamber formed on the other side. The upper chamber 12e and the lower chamber 12d are connected to one side of the switching valve 13, and are connected via the switching valve 13 to the first oil passage 9a and the return oil passage 15 connected to the tank 81. A detection switch 14 switches the switching valve 13 by detecting that the outboard motor has been lifted above the water.

In order to lower the outboard propulsion device 3 into the water, the pump 8 is reversed and the hydraulic oil is fed to the lower chamber 5b of the tilt cylinder 5 through the second oil passage 9b. As a result, the hydraulic oil in the upper chamber 5e is removed, and the oil flows back through the first oil passage 9a and is circulated to the first port 8a of the pump 8. Thus, the tilt cylinder 5 is shortened, the outboard propulsion unit 3 is lowered into the water, and the sensor 14 switches the switching valve 14 in the forward direction.

When the pump 8 is normally rotated and oil is supplied to the first oil passage 9a, the working oil is supplied to the upper chamber 5c of the tilt cylinder 5 and the upper chamber 12 of the trim cylinder 12.
e, and the outboard propulsion unit 3 is lifted above the water.
When it reaches the upper end, the detection switch 14 operates, the switching valve 13 switches from the forward direction to the reverse direction, and the hydraulic oil is supplied to the trim cylinder.
The lower chamber 12d of 12 is refueled, and the trim rod 12c retreats into the trim cylinder 12.

The above structure is not much different from the conventionally known tilt-up mechanism.

As shown in FIG. 2, the tilt cylinder 5 according to the present invention includes a main piston 7a having a piston 7 connected to a rod 6 and a free piston 7b, and a small chamber 5d is formed between the pistons. Has been done. The main piston 7a has a relatively thick first oil passage 7d having a first check valve 7c that allows only the flow of hydraulic oil from the lower chamber 5b side to the small chamber 5d side, and a second check valve that allows only reverse flow. A relatively thin second oil passage 7f having a valve 7e is installed. The first check valve 7c and the second check valve 7e
2 has a structure in which hydraulic oil flows when a certain pressure or more is applied, as shown in FIG. Main piston 7a
At the end of the stroke when the cylinder moves toward the cylinder extension side, a valve body 10 made of an annular flat plate is held in a floating state by a disc spring 11 at a position separated from the end surface by a distance S. Main piston
When the 7a moves to the vicinity of the stroke end with the free piston 7b left in the initial position and comes into contact with the valve body 10, the thick first oil passage 7d
The main piston is closed as a result of the hydraulic fluid being stopped.
Prevent further collision of 7a to avoid collision. Thus, the valve body 10 constitutes a throttle means for narrowing the sectional area of the oil passage. In this embodiment, the example in which the valve body 10 completely shuts off the oil passage is shown, but the "throttle means" is a concept including one that reduces the area of the oil passage.

Therefore, floating matter on the water collides with the outboard propulsion unit 3,
When a strong tensile force acts between the hydraulic cylinder 5a and the rod 6, the hydraulic oil in the lower chamber 5b opens the first check valve 7c and the first oil passage.
After 7d, move into small room 5d. The main piston 7a moves until the free piston 7b remains in the initial position, and the tilt cylinder 5 rapidly extends. Next, when the external force is removed, the weight of the outboard propulsion device 3 exerts a compressive force on the tilt cylinder 5, and the hydraulic oil that has moved into the small chamber 5d becomes the second check valve.
7e is opened to pass the second oil passage 7f, and the main piston 7a is slowly returned to the position of the free piston 7b.

〔The invention's effect〕

As described above, the present invention uses the piston in the hydraulic cylinder of the tilt cylinder that raises and lowers the outboard propulsion mechanism.
Among the oil chambers defined in the chamber, the oil chamber through which the piston rod penetrates is communicated with the oil passage through which the hydraulic oil is pumped when the outboard propulsion device in the hydraulic oil supply device is lowered into the water, and the hydraulic pressure An oil chamber opposite to the oil chamber with respect to the piston in the cylinder is communicated with an oil passage through which hydraulic oil is pressure-fed when the outboard propulsion device in the hydraulic oil supply device is pulled above water, and the piston is connected to the piston. , When the piston moves to the cylinder extension side, and when the piston moves to the cylinder shortening side and the first oil passage having a check valve through which hydraulic oil flows when a pressure above a certain level is applied. And a second oil passage having a check valve through which hydraulic oil flows when a pressure above a certain level is applied to each of the two pressure receiving surfaces of the piston so as to penetrate the piston. Since the throttle means for narrowing the cross-sectional area of the first oil passage is provided immediately before the piston reaches the stroke end on the cylinder extension side between the end of the Linda through which the piston rod penetrates, the outboard propulsion unit is mounted on the water surface. When a large floating substance collides, a force for extending the tilt cylinder is applied, and the hydraulic oil passes through the first oil passage of the piston, so that the piston rapidly moves to the cylinder extension side.

Therefore, the outboard propulsion device retracts above the water while extending the tilt cylinder to avoid floating objects. At this time, when the piston abruptly approaches the stroke end on the cylinder extension side, the throttle means throttles the cross-sectional area of the first oil passage to restrict passage of the working oil, so that the piston penetrates the piston rod of the hydraulic cylinder. Before it hits the end, it stops or decelerates rapidly.

After avoiding floating matter, the tilt cylinder receives a force to compress it due to the weight of the outboard propulsion unit, so that the hydraulic oil passes through the second oil passage of the piston and the piston moves toward the cylinder shortening side. It slowly moves and the outboard propulsion unit returns to the normal running state.

When pulling the outboard propulsion device above water, the hydraulic oil supply device pumps the hydraulic oil to the oil chamber on the opposite side of the oil chamber through which the piston rod of the tilt cylinder penetrates, and then the outboard propulsion device is moved into the water. When lowering the hydraulic oil, the hydraulic oil supply device pumps the hydraulic oil into the oil chamber through which the piston rod of the tilt cylinder penetrates. When hydraulic oil is pumped to the oil chamber on the opposite side of the oil chamber through which the piston rod penetrates, the piston moves to the cylinder extension side of the hydraulic cylinder, the piston rod projects from the hydraulic cylinder, and the outboard propulsion machine is pulled up. . When the hydraulic oil is pumped to the oil chamber through which the piston rod penetrates, the piston moves to the cylinder shortening side of the hydraulic cylinder, the piston rod is inserted into the hydraulic cylinder, and the outboard propulsion unit is lowered.

Therefore, it is possible to obtain the hydraulic tilting device that promptly allows the outboard propulsion device to escape rearward in the event of collision with a floating substance, and in which the piston of the tilt cylinder does not move all the way to the stroke end on the cylinder extension side.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a schematic configuration view showing an stern outboard propulsion device, and FIG. 2 is an enlarged cross-sectional view of a main part. 5 ... Tilt cylinder, 5a ... hydraulic cylinder, 5b ... lower chamber, 5c ... upper chamber, 7a ... main piston, 7b ... free piston, 5d ... small chamber, 7c ... first check valve, 7d ... first oil passage, 7e ... second check valve, 7f ... second oil passage, S ... distance,
10 ... Valve, 11 ... Spring.

Claims (3)

[Claims] Claim: What is claimed is: 1. A tilt cylinder mounted between the free end of an outboard propulsion device pivotally supported at the tail of a hull and the hull, and hydraulic oil supplied to the tilt cylinder to extend or shorten it. In a hydraulic tilt device such as an outboard motor equipped with a hydraulic oil supply device that raises and lowers the outboard propulsion device by moving the outboard propulsion device into two chambers by a piston in the hydraulic cylinder of the tilt cylinder. Among the defined oil chambers, the oil chamber penetrated by the piston rod is communicated with the oil passage through which the hydraulic oil is pumped when the outboard propulsion device in the hydraulic oil supply device is lowered into water, and the hydraulic cylinder An oil chamber opposite to the oil chamber with respect to the piston is communicated with an oil passage through which hydraulic oil is pumped when the outboard propulsion device in the hydraulic oil supply device is pulled up to the water. When the piston moves to the cylinder extension side, the first oil passage having a check valve through which hydraulic oil flows when a pressure above a certain level is applied, and when the piston moves to the cylinder shortening side And a second oil passage having a check valve through which hydraulic oil flows when a pressure of a certain level or more is applied to each of the two pressure receiving surfaces of the piston so as to penetrate the piston. Outboard, characterized in that throttling means for throttling the cross-sectional area of the first oil passage is provided immediately before the piston reaches the stroke end on the cylinder extension side between the end of the hydraulic cylinder where the piston rod penetrates. Tilting device for machines. 2. A hydraulic tilting device for an outboard motor according to claim 1, wherein the piston comprises a main piston having a piston rod and a free piston not having a piston rod. 3. The hydraulic tilting device for an outboard motor according to claim 1, wherein the throttle means is a valve plate for closing the first oil passage.