JPH045195A - Tilt cylinder device for outerboard motor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement of a gas-liquid tilt cylinder device suitable for an outboard motor.

(Prior Art) Conventionally, a marine propulsion machine (hereinafter referred to as an "outboard motor"), for example, as disclosed in Japanese Patent Publication No. 59-5480, has been employed as a propulsion means for small boats. With this outboard motor, when the outboard motor collides with an underwater obstacle while moving forward, the gas inside the cylinder contracts, and the piston subsequently moves under the action of the relief valve inside the piston to attenuate the impact force. The unique feature is that the outboard motor is protected from damage due to the outboard motor.

(Problems to be Solved by the Invention) Even when traveling in shallow water, a ship may not only move forward but also back up (hereinafter referred to as "astern"), and when moving backward, there is a risk of receiving an unexpected external force from the direction of travel. The aforementioned Tokuko Sho 5
With the technology of the outboard motor No. 9-5840, the only way to maintain the posture when traveling in shallow water is by using a horizontal retaining bottle and a mechanical reverse locking means, and therefore, under this operating condition, external forces cannot be buffered. I can't wait.

(Means for Solving the Problems) The present invention provides collision countermeasures for both forward and reverse movement, and the tilt cylinder device thereof has a cylinder arranged substantially vertically so that the piston rod moves downward. The tip of the rod is locked to a stern bracket, then locked to a cylinder or swivel case, a piston is fitted into the cylinder, a free piston is fitted onto the piston, and a gas higher than atmospheric pressure is filled above the free piston. a one-way valve provided with a gas chamber and capable of flowing hydraulic oil in a first chamber above the piston to a second chamber below the piston;
A first pressure relief chamber is provided in which the hydraulic oil in the second chamber can flow to the first chamber only when the pressure in the second chamber becomes higher than the pressure in the first chamber by a certain value, and the cylinder is provided with a free piston and a first pressure relief chamber. A communication path is provided that communicates the third chamber defined between the gas chamber and the second chamber, and the pressure in the third chamber is connected to the second chamber.
The present invention is characterized in that a second pressure relief valve that opens when the pressure in the chamber becomes higher than a certain value is provided, and a manual opening/closing mechanism is attached to this second pressure relief valve.

(Function) If excessive external force is applied to the outboard motor while moving forward,
a first pressure relief valve opens to allow lowering of the piston;
The outboard motor body can rise.

Further, if an excessive external force is applied while moving backward in shallow water, the second pressure relief valve opens to allow the piston and free piston to rise, and the outboard motor body can descend.

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

FIG. 1 is a side view of the outboard motor according to the present invention, in which a stern bracket 2 is fixed to the stern plate B of the hull, and a swivel case 4 is connected to the stern bracket 2 via a horizontal bin 3.
is locked, a swivel shaft 5 passes vertically through this swivel case 4, and a mount rubber 6a is attached to this swivel shaft 5.

The outboard motor 1, in which the outboard motor body 7 is supported via the stern bracket 6b and the tilt cylinder device 10 is interposed between the stern bracket 2 and the swivel case 4, is employed in a small boat.

Figure 2 is I! of Figure 1! This is an enlarged view of the stern bracket 2, with a swivel case 4 attached to the top of the stern bracket 2 via a horizontal pin
The pressure portion 11a of the cylinder 11 of the tilt cylinder device 10 is also locked to the swivel case 4. Further, the tip of a piston rod 12 installed downward into the cylinder 11 is locked to the lower part of the stern bracket 2 via a pin 8.

FIG. 3 is a cross-sectional view of the main part of the tilt cylinder device, in which a piston 13 integrated with a piston rod 12 and a free piston 14 are fitted into the cylinder 11 from bottom to top, and a gas chamber 15 of the free piston 14 is fitted into the cylinder 11. is formed. This gas chamber 15 is filled with compressible gas having a pressure higher than atmospheric pressure.

The port 1 is attached to the piston 13 due to the weight of the outboard motor.
A one-way valve 16 in which a ball 16b is urged upward in the drawing by a weak spring 16a that allows movement of the ball 6b (downward in the drawing);
The first pressure is applied when the hole 17b is urged downward in the figure by a strong spring 17a, which prevents the movement of the ball 17b under normal backward thrust and allows it to move (upward in the figure) against excessive external force during forward movement. A relief valve 17 is provided extending vertically through the piston 13. For convenience of the following explanation, piston 13
The space above the free piston 14 and below the free piston 14 is called a first chamber C1, the space below the piston 13 is called a second chamber C2, and the space above the free piston 14 and below the gas chamber 15 is called a third chamber C3. .

The cylinder 11 is further provided with a communication path 18'' that communicates the second chamber C2 and the third chamber C3, and a second pressure relief valve 1 consisting of a strong spring 19a and a ball 19b is attached to the communication path 18.
9 is interposed therein, and the second pressure relief valve 19 includes an eccentric cam 21 and a handle 22 that fits onto the shaft 21a of the cam to swing the cam 21. A mechanism 20 is attached.

The operation of the tilt cylinder device for an outboard motor having the above configuration will be described below.

4 to 7 are action explanatory views, and FIG. 4(a) shows the outboard motor in forward movement, and the tilt cylinder device 10 at this time.
As shown in Figure 4(b), the first and second pressure relief valves 1
7.19 are both closed, so the first chamber C1 and the second chamber C2
There is no movement of hydraulic oil between the third chamber 03 and the third chamber 03.

If an excessive force F5 (Fig. 5 (a)) is applied to the outboard motor during forward movement, the piston rod 12 is relatively pulled out (arrow ■) as shown in Fig. 5 (b), and the second chamber C2 The pressure of
It flows into the chamber C1, and the piston 13 descends by that amount.

When receiving the large external force F5, the outboard motor main body 7 quickly rises, making it possible to avoid damage thereto.

FIG. 6(a) shows the outboard motor when traveling astern in shallow water, and by forcibly opening the second pressure relief valve 19 with the handle 22, the second chamber C2 and the third chamber C3 are communicated with each other. This allows the outboard motor main body 7 to be raised artificially, as shown in Figure 6 (
When the second pressure relief valve 19 is closed at the position a), the piston 13 becomes immobile, and the outboard motor main body 7 is held by the tilt cylinder device 10 at a free angle (inclination).

FIG. 7(a) shows the outboard motor when it receives a large external force F7 while moving backward, and the piston rod 12 tries to rise (arrow ■). When the pressure in the third chamber C3 increases strongly and exceeds a certain value, the second pressure relief valve 19 opens and the hydraulic oil is discharged from the third chamber C3.
3 to the second chamber C2 (arrow ■), thereby avoiding damage to the outboard motor main body 7.

FIG. 8 is a diagram showing another embodiment of FIG. 3, and is characterized by the fact that the first pressure relief valve 17 and one-way valve 16 in FIG. 3 have been standardized. Since the other parts are the same as those in FIG. 3 except for this legalization valve, the explanation will be omitted.

FIG. 9 is an enlarged view of the integrated valve shown in FIG. 8, where 31 is a valve seat housed in the recess 13a so as to be able to move up and down, 32 is a ball, and 33 is a ball that allows movement of the ball 32 by the weight of the outboard motor. A weak spring 34 prevents the valve seat 31 from moving under normal thrust, and a strong spring 35 allows the valve seat 31 to move (upward in the figure) against excessive external force.
A is a push bottle protruding from the retainer 35.

The hydraulic fluid in the first chamber C1 passes through the through hole 36, pushes down the ball 32, and flows into the second chamber C2 through the lower through hole 37.

When the pressure in the second chamber C2 rises abnormally, the valve seat 31 moves upward in the drawing due to this pressure, and the push pin 35a restricts the rise of the hole 32. Therefore, the hydraulic oil is in the second chamber C2.
and flows into the first chamber C1.

In the case of Fig. 8, one recess 13a restricts the flow of hydraulic oil in two directions, so it is necessary to install one recess in each direction when the piston diameter is small. Increased degree of freedom in numbers.

(Effects of the Invention) As described above, according to the present invention, it is possible to extend the life of the outboard motor by avoiding damage to the outboard motor body due to collisions when moving forward or astern in shallow areas, and also to extend the life of the outboard motor. By operating the pressure relief valve on the handle, the angle of the outboard motor body can be changed freely, making the outboard motor easier to handle.

[Brief explanation of the drawing]

Fig. 1 is a side view of an outboard motor according to the present invention, Fig. 2 is an enlarged view taken in the direction of arrow II in Fig. 1, Fig. 3 is a sectional view of main parts of the tilt cylinder device, Figs. 4 to 7. 8 is an explanatory diagram of the operation, FIG. 8 is a diagram of another embodiment of FIG. 3, and FIG. 9 is an enlarged view of the integrated valve of FIG. 8. 1... Outboard motor 2... Stern bracket 4
...Swivel case 7...Outboard motor body 10...
Tilt cylinder device 11...Cylinder 12...Piston rod 1
3...Piston 14...Free piston 15
...Gas chamber 16...One-way valve 17...First pressure relief valve 18...Communication path 19...Second pressure relief valve 20...Manual opening/closing mechanism B...Stern plate C1 ...
1st Office C2... 2nd Office C3... 3rd Office Patent Applicant Agent for Honda Motor Co., Ltd.
Patent Attorney Part 2 1) Part 1 Patent Attorney
Kuni Ohashi Patent Attorney Small
Yama Yu Figure 2 Figure 3 Figure 9 Figure 8

Claims (1)

[Claims] A swivel case is pivotally supported on a stern bracket fixed to the hull so as to be able to swing up and down, an outboard motor body is rotatably supported on the swivel case, and between the stern bracket and the swivel case, In an outboard motor equipped with a tilt cylinder device, in the tilt cylinder device, the cylinder is placed substantially vertically so that the piston rod advances downward, and the tip of the piston rod is locked to a stern bracket, and the cylinder is swiveled. A piston is secured to the case, a free piston is fitted into the cylinder, and a free piston is fitted above the piston, and a gas chamber filled with gas at a pressure higher than atmospheric pressure is provided above the free piston. A one-way valve that allows the hydraulic oil in the first chamber to flow to the second chamber below the piston, and a one-way valve that allows the hydraulic oil to flow into the second chamber below the piston.
A first pressure relief valve is provided in the cylinder to allow hydraulic fluid in the chamber to flow into the first chamber, the cylinder being provided with a third chamber defined between the free piston and the gas chamber in communication with the second chamber. A communication path is provided, and a second pressure relief valve that opens when the pressure in the third chamber becomes higher than the pressure in the second chamber by a certain value is interposed in the communication path, and the second pressure relief valve is equipped with a manual opening/closing mechanism. A tilt cylinder device for an outboard motor, characterized in that it is equipped with a.