JP3492729B2 - Hydro assist device for marine propulsion unit - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydro-assist and shock absorber device disposed between a hull and a propulsion device slidably mounted on the hull. More specifically, the present invention relates to a switching valve that can be maintained at a desired trim angle and can return a trim position in the event of a driftwood collision, and an improvement in a structure around a piston in a cylinder. 2. Description of the Related Art In small and medium-sized ships, the tilt operation force when the propulsion unit is tilted up and down is reduced, and the impact force when the propulsion unit collides with driftwood or the like during sailing is absorbed. In many cases, the hydro-assist device is disposed between the hull and the propulsion device. [0003] As an example of such a hydro assist device, there is a conventional one shown in Figs. The hydro assist device 50 connects an upper end 51a of a cylinder 51 to a propulsion device, connects a protrusion 53a of a rod 53 of a piston 52 inserted into the cylinder 51 to a hull, and 54 and lower chamber 55
Through a hydraulic passage 56, and
And a switching valve 57 is provided.
Hydraulic oil A is sealed in the two chambers 54 and 55, and high-pressure gas B is sealed in the upper part of the upper chamber 56. This gas pressure reduces the operating force when tilting up. The piston 52 is provided with a return valve 52a and an absorber valve 52b. The switching valve 57 is connected to the hydraulic passage 5
At the upper end of 6, a communication passage 56a facing the upper chamber 54 is formed so as to communicate therewith, a ball 58 is disposed in a communication portion of both passages, and the ball 58 is biased toward the closing side by a spring 59. . A pin 60 is inserted into the communication passage 56 a of the switching valve 57 so as to be able to advance and retreat in a direction perpendicular to the direction, and the tip surface of the pin 60 is in contact with the ball 58.
The pin 60 presses the ball 58 in the opposite biasing direction by rotating the cam member 61, thereby causing the passage 5 to move.
6 is opened (see FIGS. 9 and 10). By the way, as apparent from FIG. 11, when a load acts on the switching valve 57 in the direction in which the piston rod 53 extends, the ball 58 blocks the passage. Therefore, although it functions as a lock mechanism at the time of reverse running, it does not have a thrust holding function at the time of contraction, that is, at the time of forward movement. In order to secure this thrust holding function to some extent, the spring force of the spring 59 is set to be large, and the closed state is held to a certain region by the spring force. [0006] However, when the spring force of the spring 59 is increased, the switching operation load is correspondingly increased, which causes a problem that the operability is deteriorated. On the other hand, in order to make it possible to hold the thrust at the time of forward movement while avoiding an increase in the switching operation load, the hydraulic passage can be shut off in both directions and the piston 5
The second return valve 52a may be eliminated. However, in the above structure, when the piston rod 53 is extended by the collision of the propulsion machine with a driftwood or the like during cruising, the tilt-down operation is not performed to the original trim position after the extension. As a result, the propulsion device remains exposed above the water surface, and in some cases, the engine may seize. The present invention provides a hydro-assist device for a marine propulsion device which can hold both forward and reverse thrusts at a desired trim angle and can automatically return to the original trim angle after driftwood collision. It is aimed at. SUMMARY OF THE INVENTION Accordingly, the present invention provides an axially sliding piston in a cylinder connected to one of a hull and a propulsion device swingably mounted on the hull. Movably inserted to define the inside of the cylinder as upper and lower hydraulic chambers,
A piston rod is connected to the other of the hull and the propulsion unit, high-pressure gas is sealed in the upper hydraulic chamber, and damping that allows only the flow from the lower hydraulic chamber to the upper hydraulic chamber in the first internal passage of the piston. A valve is provided in each of the second internal passages with a return valve that allows only a flow from the upper hydraulic chamber to the lower hydraulic chamber, and an oil that communicates with the upper and lower hydraulic chambers.
In hydro assist device of marine propulsion device constituted by arranging a switching valve pressure passage, slidably disposed the free piston to the upper hydraulic chamber in the axial direction, the switching bar
Lube is connected to the hydraulic passage and the hydraulic passage.
Flow from the upper hydraulic chamber to the lower hydraulic chamber
Shut off both flow from hydraulic chamber to upper hydraulic chamber
Between the cylinder and the switching valve
Valve body that moves in a direction substantially perpendicular to the direction of use, and the valve
And a ball supported by the body.
When the valve body is moved to the shutoff position, the ball
The hydraulic passage is closed in accordance with the passage, and the valve body is connected.
When the ball is moved to the
It is characterized in that the hydraulic passage is communicated. According to the hydro-assist device for a marine propulsion device according to the present invention, when the switching valve is located at the shut-off position, the flow from the upper hydraulic chamber to the lower hydraulic chamber and the lower hydraulic chamber are performed. Both the flow from the hydraulic chamber to the upper hydraulic chamber is blocked, so that the thrust can be held both at the time of advancing and at the time of reversing at a desired trim angle. In the present invention, the switching valve shuts off the hydraulic passage in both directions during sailing, and when it collides with a driftwood or the like in this state, a force in the extension direction acts on the piston rod, and the lower hydraulic chamber is closed. When the hydraulic pressure rises and the hydraulic oil in the lower hydraulic chamber flows between the piston and the free piston through the damping valve, the impact force is absorbed, and the movement of the hydraulic oil causes the piston rod to extend and propell. The aircraft is flipped up. On the other hand, after the absorption of the impact force, a propulsive force in the contraction direction or its own weight acts on the piston rod, and the hydraulic oil between the piston and the free piston returns to the lower hydraulic chamber through the return valve. As a result, the piston rod contracts, and the thruster automatically returns to the original trim angle.
Also, the switching valve is turned in a direction perpendicular to the hydraulic action direction.
The switching operation is performed in such a way that the switching valve is
Operating force is significantly lighter than when operating against pressure
Can be reduced. An embodiment of the present invention will be described below with reference to the drawings. 1 to 7 are views for explaining a hydro-assist device for a marine propulsion device according to an embodiment of the present invention. FIG. 1 is a sectional front view, FIG. 2 is an enlarged sectional view of a main part, and FIG. 4 and 5 are cross-sectional side views showing the state of the switching valve, FIG. 6 is a side view showing an outboard motor on which the apparatus of the embodiment is mounted, and FIG. 7 is a hydraulic circuit diagram of the apparatus of the embodiment. is there. In each of the drawings, reference numeral 1 denotes a hull on which the apparatus of the present embodiment is mounted, and an outboard motor (propulsion device) 2 is disposed at the stern 1a of the hull 1 so as to be swingable. In this outboard motor 2, an upper case 4b is connected to an upper part of a lower case 4a in which the screw 3 is disposed, an engine 5 is mounted on the upper case 4b, and the screw 3 is driven to rotate by the engine 5. It is configured as follows. A clamp bracket 6 is attached and fixed to the stern 1a. An upper edge 7a of a swivel arm 7 is pivotally supported on the bracket 6 via a tilt shaft 8. The outboard motor 2 is mounted and fixed to the swivel arm 7 so that the outboard motor 2 can swing up and down with respect to the hull 1. The hydro-assist device 10 of this embodiment is disposed between the clamp bracket 6 and the swivel arm 7. In this hydro device 10, a piston 14 is inserted and slidably inserted in an axial direction into a cylinder 11 whose upper end is closed, and one end 12a of a piston rod 12 is fixedly connected to the piston 14; Part 12b
With the lid member 13 inserted in the lower end opening of the cylinder 11
And projecting outward. The upper end 11a of the cylinder 11 is connected to the swivel arm 7 by the other end 1 of the piston rod 12.
2b are rotatably connected to the clamp bracket 6, respectively, so that the outboard motor 2 swings as the piston rod 12 expands and contracts. In the cylinder 11, the piston 14
Thus, an upper hydraulic chamber 15 and a lower hydraulic chamber 16 are defined. The two hydraulic chambers 15 and 16 are filled with hydraulic oil A ′, A, and a high-pressure gas B is filled above the hydraulic oil A ′ in the upper hydraulic chamber 15. The piston 14 has one or more communication holes (second internal passages, first internal passages) 17a and 17b communicating with the upper and lower hydraulic chambers 15 and 16, respectively. A return valve 18 and an absorber valve (attenuation valve) 19 are provided in each of the communication holes 17a and 17b. A bulging portion 11b is provided on the outer wall of the cylinder 11.
Are formed integrally along the cylinder axis, and a hydraulic passage 20 is formed in the bulging portion 11b. The lower end of the passage 20 opens to the lower end of the cylinder 11 and communicates with the lower hydraulic chamber 16. The upper end of the passage 20 opens slightly below a step portion 22 (described later) in the cylinder 11. And communicates with the upper hydraulic chamber 15. A switching valve 25 is provided at an upper end of the hydraulic passage 20. The switching valve 25 has a structure in which one end of an operation rod 27 is fixed to the axis of a disk-shaped valve body 26 rotatably disposed in a valve hole 11c recessed in a direction perpendicular to the cylinder axis. is there. A valve seat 28 is provided outside the valve body 26, and the valve seat 28 is non-rotatably fixed by a lid member 29 fixed to the cylinder 11. Reference numeral 20b denotes a valve seat on the side of the opening 20a, which has a communication hole coaxial with the opening 20a. The valve seat 28 has a communication hole 28.
a is formed so as to be coaxial with the opening 20 a of the passage 20, and the valve seat 28 and the lid 2
9, an annular communication passage 29a for communicating the hydraulic passage 20 with the communication hole 28a is formed. The opening 2 of the valve body 26
0a, a long hole 26a is provided with an operation rod 27.
Are formed in an arc shape centered on the axis. The elongated hole 26a has an elliptical large-diameter portion 26b and an elliptical small-diameter portion 26c following the elliptical large-diameter portion 26b.
Either 6b or the small diameter portion 26c matches the opening 20a and the communication hole 28a. Two balls 31, 31 are provided in the large diameter portion 26b in the elongated hole 26a.
A spring 32 for urging the two outwardly between the first and the 31st.
Are arranged. The large diameter portion 26b is connected to the opening 20.
a and the communication holes 28a, the balls 31, 31 are respectively opened 20a and the communication holes 28a of the valve seat 28.
Are closed in both directions, and the small diameter portion 26c is
a, the hydraulic passage 20 communicates with the communication hole 28a. As shown in FIG. 6, an arm 33 is fixedly connected to the operation rod 27, and one end of a cable 34 is connected to the arm 33. The other end of the cable 34 is connected to an operation lever 35 provided on the outer wall of the engine 5 of the outboard motor 2.
Is opened and closed. The cable 34 is fixed to the cylinder 11 by a clamp member 36 in the middle. This is to prevent the cable 34 from interfering with other components during the tilt up / down operation, thereby improving the durability of the cable 34. A free piston 21, which is a feature of the present embodiment, is slidably disposed in the upper hydraulic chamber 15 in the cylinder 11 in the axial direction.
1 can be separated from the piston 14. An oil introduction portion 21a whose outer diameter is set slightly smaller than that of the lower portion is formed at the upper portion of the free piston 21. Further, an oil communication groove 21b is formed in the upper surface of the head of the free piston 21. The groove 21b communicates the oil introduction portion 21a with the upper hydraulic chamber 15. A stopper 22 having a smaller diameter than the free piston 21 is formed in the upper hydraulic chamber 15 of the cylinder 11 so as to be stepped.
Numeral 2 is located slightly above the opening 20a of the hydraulic passage 20 facing the upper hydraulic chamber 15. This stopper portion 22
Restricts the rising end position of the free piston 21 to a position where the oil introduction portion 21a does not rise above the opening 20a. Next, the operation and effect of this embodiment will be described. In the hydro-assist device 10 of the present embodiment, the switching valve 25 is operated by operating the operation lever 35 during cruising.
The large diameter portion 26b of the long hole 26a is
a, and is turned to the blocking position (the position shown in FIG. 3) corresponding to the communication hole 28a. As a result, both the flow of oil from the upper hydraulic chamber 15 to the lower hydraulic chamber 16 and the flow in the opposite direction are blocked, and the expansion and contraction of the piston rod 12 is locked. As a result, the outboard motor 12 can hold the thrust during both forward movement and reverse movement, and can be adjusted to a desired trim angle. Here, the operating direction of the hydraulic pressure of the operating oil on the switching valve 25 coincides with the axial direction of the operating rod 27, while the moving direction of the switching valve 25 is at right angles to the operating rod 27. . Therefore, the switching valve 25 of the present embodiment moves in the direction perpendicular to the direction of the hydraulic pressure. If the outboard motor 2 collides with a driftwood or the like during sailing, the piston rod 12 is pulled in the direction of extension by the impact force, and the hydraulic pressure in the lower hydraulic chamber 16 rises. The absorber valve 19 is opened, hydraulic oil flows between the piston 14 and the free piston 21, the piston rod 12 is extended, and the outboard motor 2 jumps upward. When the hydraulic oil passes through the absorber valve 19, the impact force is absorbed. After absorbing the impact, the piston rod 12 is urged in the contracting direction by the own weight or the propulsive force of the outboard motor 2. Therefore, the free piston 21 and the piston 1
4 returns to the lower hydraulic chamber 16 through the return valve 18 through the return valve 18, and the outboard motor 2
Automatically returns to the original trim position. Further, when adjusting the trim angle of the outboard motor 2 to a more vertical side during sailing, the switching valve 25 is turned to the communicating position. Then, the piston rod 12 is urged to the contraction side by the propulsion force, and the hydraulic oil in the upper hydraulic chamber 15 moves into the lower hydraulic chamber 16 via the hydraulic passage 20,
As a result, the piston rod 12 contracts, and the outboard motor 2 swings more vertically. When the desired trim angle is reached, the switching valve 25 is turned to the shut-off position. On the other hand, when the outboard motor 2 is tilted up, the switching valve 25 is rotated to a communication position (a position shown in FIG. 4) where the small diameter portion 26c of the long hole 26a coincides with the opening 20a. Then, the hydraulic passage 20 communicates and the high-pressure gas B
Hydraulic fluid in the lower hydraulic chamber 16 is
Through the upper hydraulic chamber 15, whereby the piston rod 12 is extended. As a result, the tilt operation force when the outboard motor 2 is moved above the water surface is reduced. As described above, according to the hydro assist device 10 of this embodiment, the switching valve 25 is connected to the upper hydraulic chamber 1.
5 to the lower hydraulic chamber 16 and the flow in the opposite direction can be shut off, so that both forward and reverse thrust holding is possible, and thrust holding at a desired trim angle is possible. Is possible, it is possible to easily respond to changes in running conditions, environmental conditions, and the like, and to improve maneuverability. Further, according to the present embodiment, the switching valve 25
The switching operation is performed by rotating the valve in the direction perpendicular to the hydraulic pressure direction, so the operating force can be greatly reduced compared to the case where the switching valve is operated against the hydraulic pressure. Can be improved. The piston 14 has an absorber valve 1
7b, the return valve 17a is provided, and the free piston 21 is provided in the upper hydraulic chamber 15 so that the impact force when the outboard motor 2 collides with a driftwood or the like during cruising is reduced to the lower hydraulic chamber 16
Can be absorbed when flowing between the piston 14 and the free piston 21 through the damping valve 17b, and after the absorption of the impact force, the outboard motor 2 is automatically returned to the original trim angle. be able to. Further, in this embodiment, the stopper portion 2 for restricting the rising end position of the free piston 21 in the upper hydraulic chamber 15 is provided.
2, the oil level of the hydraulic oil A 'in the upper hydraulic chamber 15 can be set near the upper surface of the free piston 21, and the overall length of the cylinder 11 can be reduced.
A hydraulic oil introduction unit 21 is provided above the free piston 21.
a, the opening 20a of the hydraulic passage 20 can be located in this portion, and the overall length of the cylinder can be reduced from this point as well. It can be easily adopted for outboard motors. When the rising end position of the free piston 21 is not restricted, the high-pressure gas B
In order to avoid inflow into the
The dimension from the head surface to the oil level is set relatively large, and the opening of the hydraulic passage 20 is located in this portion, so that the entire cylinder length becomes longer. As described above, since the entire apparatus can be made smaller while providing the free piston 21, it is possible to prevent the clamp bracket 6 from protruding below the transom board, which is a concern when the free piston is provided, and to generate splash and speed. The problem of degradation can be avoided. As described above, according to the hydro-assist system for a marine propulsion device according to the present invention, the switching valve is configured to block the flow of the hydraulic oil in both directions, so that the desired trim angle is obtained. In this case, the thrust can be held both during forward movement and during reverse movement, and there is an effect that maneuverability can be improved. Since the piston is provided with the damping valve and the return valve, and the free piston is disposed in the upper hydraulic chamber, it is possible to absorb the impact at the time of collision with driftwood, and to automatically return after the impact is absorbed. This also has the effect of improving maneuverability. The switching valve is hydraulically operated.
Switch operation by rotating in the direction perpendicular to the
Therefore, when operating the switching valve against hydraulic pressure,
The operating force can be greatly reduced compared to the
This has the effect of improving workability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional front view of an outboard motor hydro-assist device according to an embodiment of the present invention. FIG. 2 is an enlarged sectional view of a main part of the apparatus of the embodiment. FIG. 3 is a side view of the apparatus of the embodiment. FIG. 4 is a cross-sectional view showing a state in which a hydraulic passage of a switching valve of the embodiment device is shut off. FIG. 5 is a cross-sectional view showing a communication state of a switching valve of the apparatus of the embodiment. FIG. 6 is a side view showing an outboard motor in which the apparatus of the embodiment is provided. FIG. 7 is a hydraulic circuit diagram of the embodiment device. FIG. 8 is a view showing a conventional hydro assist device. FIG. 9 is a sectional plan view showing a conventional switching valve. FIG. 10 is a cross-sectional view showing a shut-off state and a communication state of a conventional switching valve. FIG. 11 is a hydraulic circuit diagram of a conventional hydro assist device. [Description of Signs] 1 Hull 2 Outboard motor (propulsion device) 10 Hydro assist device 11 Cylinder 12 Piston rod 14 Piston 15 Upper hydraulic chamber 16 Lower hydraulic chamber 17a Return valve 17b Damping valve 20 Hydraulic passage 21 Free piston 25 Switching valve 31 Ball (seal part) B High pressure gas

Continuation of front page (56) References JP-A-4-5195 (JP, A) JP-A-4-129399 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B63H 20 / 08

Claims (1)

(57) [Claim 1] A piston is slidable in an axial direction in a cylinder connected to one of a hull and a propulsion device swingably disposed on the hull. Insert the cylinder inside,
A lower hydraulic chamber is defined, a piston rod is connected to either the hull or the propulsion unit, high-pressure gas is sealed in the upper hydraulic chamber, and a first internal passage of the piston is moved from the lower hydraulic chamber to the upper hydraulic chamber. A damping valve that allows only flow to the chamber
A return valve is provided in the internal passage for allowing only the flow from the upper hydraulic chamber to the lower hydraulic chamber, and a switching valve is disposed in a hydraulic passage communicating the upper and lower hydraulic chambers. In the hydro assist device, a free piston is slidably disposed in the upper hydraulic chamber in an axial direction, and the switching valve is connected to the hydraulic passage so as to communicate with the hydraulic passage.
Passage position and the hydraulic passage from the upper hydraulic chamber to the lower hydraulic chamber.
Flow from the lower hydraulic chamber to the upper hydraulic chamber.
Between the cylinder and the shut-off position
The valve moves in a direction substantially perpendicular to the direction of pressure applied to the valve.
A valve body and a ball supported by the valve body.
And move the valve body to the shut-off position.
And the ball coincides with the hydraulic passage and closes the hydraulic passage
When the valve body is moved to the communication position, the ball
A hydro-assist device for a marine propulsion device, wherein the hydraulic assist device is disconnected from a hydraulic passage and communicates with the hydraulic passage .