JPH0314091B2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a vibration damping device that reduces vibrations generated in the hull of a ship powered by an internal combustion engine, etc.
This invention relates to a rotary vibration damping device that operates with a minimum amount of energy by making the vibration force variable.

Background Art Today's ships often use reciprocating internal combustion engines such as diesel engines as power sources.
BACKGROUND ART How to reduce engine-generated vibrations, especially ship body vibrations that resonate with the engine vibrations, is a major issue in achieving comfortable running performance of ships.

As a vibration damping method to reduce this hull vibration,
There is a way to reduce the vibrations generated by the engine by installing a counterbalancer that rotates in the opposite direction to the crankshaft on the engine itself, but for example, installing such a device on an internal combustion engine for a large ship will increase the size of the engine. The price has skyrocketed and it is not common.

In addition, a vibration damping device has been proposed that is installed on a ship's hull and applies vibration whose phase is adjusted to the vibration frequency of the ship's hull to reduce hull vibration. Specifically, a pair of rotating bodies each having a weight attached thereto are rotated in opposite directions by an electric motor, thereby canceling the horizontal vibration caused by the weight and generating vertical vibration. Although this device has the advantage of simple construction, the excitation force cannot be changed during operation of the device. In other words, when the hull vibration changes, or depending on the type of hull vibration, it is necessary to change the excitation force, but the above-mentioned electric vibration damping device generates vibration from the weight of the rotating body, so it is necessary to stop operation. The weight must be replaced with a weight of the required weight, and the weight of the weight can only be changed in steps.

In addition, since an electric motor is used to drive the rotating body, a large amount of electric power is required to start the rotating body, and a method is usually used to induce rotation by rocking the rotating body at the time of starting. Rotational speed control is necessary to adjust the vibration period and obtain the optimal excitation mode, which creates problems in that electromagnetic brakes, electromagnetic couplings, and expensive electric control devices are indispensable to control them. Ta.

Purpose of the Invention In view of the current state of rotary vibration damping devices that are installed on a ship's hull to reduce ship vibration, the present invention provides a vibration damping device that can freely change the vibration frequency and excitation force applied to the ship's hull during operation, and The aim is to create a vibration damping device that can be operated with low energy consumption without consuming a large amount of energy to obtain the excitation force, and also to create a rotary vibration damping device that is simple in structure, easy to operate, and inexpensive. The purpose is

DISCLOSURE OF THE INVENTION The present invention provides a rotary excitation type vibration damping device that generates vibration in a vertical direction by rotating a pair of rotating bodies in opposite directions to each other, in which a pair of eccentric weights having the same rotational moment inside the rotating bodies is used. are arranged coaxially, one of the eccentric weights is fixed, and the other is rotatable in a cylindrical cavity separated in the rotational direction by a fixed piece with pressure oil ports on both sides, with the movable side being the fixed side. This rotary excitation type vibration damping device is characterized in that the position of the eccentric weight on the movable side relative to the fixed side is made variable by supplying pressure oil to both sides of the fixed piece, with the axially symmetrical position as the fixed position.

In the rotary vibration damping device according to the present invention, the rotating body has a pair of unbalanced weights, and one of the unbalanced weights can freely change its position in the rotational direction relative to the other fixed side unbalanced weight by supplying pressure oil. The excitation force can be obtained by multiplying the sum of the product of the mass of each unbalanced weight and the distance of each unbalanced weight from the axis by the square of the angular velocity. Vibration force can be set freely.

When the rotating body is started, the excitation force is 0 because the unbalanced weight on the movable side is rotated 180 degrees with respect to the fixed side, that is, at a fixed position that is axially symmetrical.
It does not require a large drive torque, has excellent rotation start-up performance at startup, and has the advantage of good responsiveness.

In addition, the center of gravity of the eccentric weight can be moved by supplying pressure oil or by mechanically holding it with a stopper and link that can be set at any position after supply, making it simple and superior in controllability compared to electrical control devices. It's cheap.

An example of the configuration of a rotating body will be described below based on the drawings. FIG. 1 is a longitudinal sectional front view of a rotating body according to the present invention, and FIG. 2 is an explanatory sectional view taken along the - line in FIG. 1. FIG. 3a is the same side view as FIG. 1, and FIG. 3b is a perspective explanatory view showing details of the engaging portion between the rotary arm and the stopper.

The rotating body 1 includes a cylindrical housing 3 fixed to a rotating shaft 2 with a key and having a partition wall in the center.
and a pair of unbalanced weights 4 and 5 inside the housing 3, one unbalanced weight 4 is fixed to one end side of the housing 3, and the other approximately semicircular unbalanced weight 5 is fixed to the other side of the housing 3. It is pivotably supported within the cavity and can rotate, and this cavity is connected to the housing 3.
A circular cover 6 is secured to the end face with bolts 7 via a seal to seal it.

A fixed piece 8 is fixed at a position above the perpendicular line inside this cavity, and two oil passages each communicating with pressure oil ports 10 and 11 opened on both circumferential sides of this fixed piece 8 are connected to the fixed piece. It is formed on both sides in the axial direction, and communicates with a pressure oil supply oil passage 9 that passes through the rotating shaft 2 and is connected via a rotary joint. Furthermore, a recess on which pressurized oil acts is provided on the circumferential end surface of the movable biased weight 5.

Therefore, the unbalanced weight 5 on the movable side is configured to be rotated by supplying pressure oil to either of the pressure oil ports 10, 11 of the fixed piece 8.

In addition, the movable side eccentric weight 5 is in its normal position as shown in Fig. 2, and at this time, it is in an axially symmetrical position with respect to the stationary side eccentric weight 4, and the moment due to the rotational force of the rotating body 1 is 0. .

In addition, the movable side biased weight 5 has a bearing portion that is a boss 5a that protrudes outside the cover 6 in the axial direction, and a rotating arm 12 is fixed to the tip of the protruding portion with a bolt 13. is arm pin 1
4 protrudes toward the cover 6 side.

A semi-circular rack groove 15 is provided on the outer surface of the cover 6 at the rotation locus position of the rotary arm 12. A stopper 17 is provided at the center of the rack groove 15 and can be attached to any position with a bolt 16. It is constructed so that it can be fixed. It goes without saying that the back surface of the stopper 17 has a rib that engages with the rack groove 15.

This stopper 17 has an approximately L-shaped fixing link 18 with a pin 19 on the back side of the stopper 17.
The outer peripheral end of the fixing link 18 is stretched in the circumferential direction with a spring 20, and the fixing link 18 is
Right rotation is restricted. Also, fixed link 1
The other end of the arm pin 8 is formed into a hook shape so that the arm pin 14 of the rotary arm 12 comes into contact with the link 18 and then fits into the inner groove thereof.

Therefore, when pressure oil is supplied to the pressure oil port 11, the movable eccentric weight 5 rotates to the left from the fixed position, and the rotating arm 12 also rotates in the same direction. When the rotating arm 12 approaches the stopper 17, the arm pin 14 engages the inclined portion at the tip of the fixing link 18.

The arm pin 14 rotates the fixing link 18 clockwise around the pin 19 against the force of the spring 20, and the arm pin 14 fits into the groove on the inner circumferential surface of the fixing link 18, and at the same time, the rotating arm 12 moves to the stopper 1.
7, the movable biased weight 5 is stopped at an arbitrary position where the stopper 17 is secured to the rack groove 15, and is held by the fixing link 18.

If the force of the spring 20 of the fixing link 18 is set so as to overcome the inertia force due to acceleration and deceleration due to the rotation of the rotating body 1 and hold the movable side biased weight 5, the position of the biased weight 5 can be maintained without supplying pressure oil. .

The pressure oil that resists this spring 20 force is transferred to the pressure oil port 10.
, the right end surface of the movable unbalanced weight 5 is pressurized and the unbalanced weight 5 starts rotating clockwise.

The arm pin 14 of the rotary arm 12 integrated with the movable eccentric weight 5 rotates the fixing link 18 in the right direction against the force of the spring 20,
8, the movable biased weight 5 can be rotated to the home position.

As described above, the rotating body according to the present invention can be started with a minimum driving force if rotation is started when the movable eccentric weight 5 is in a fixed position. By selecting the oil supply port and adjusting the supply amount, it can be rotated to any position and the excitation force can be selected as appropriate. Furthermore,
By appropriately selecting the position of the stopper installed on the cover, the limit of the excitation force can be set freely.

Embodiment An embodiment of the rotary vibration damping device according to the present invention will be described below. FIG. 4 is a top view of the vibration damping device.

The entire device is placed on a pedestal 30, and this pedestal 3
0 is fixed to a vibrating location such as a ship's hull.

In the rotary excitation type vibration damping device according to the present invention, a pair of rotating bodies 1 having the above-mentioned configuration are mounted on rotating shafts 2, 2 each having both ends supported by bearings 31, and each rotating shaft 2 has a penetrating shaft. It is configured to rotate in opposite directions by a pair of gears 32 and 33 that mesh with each other, and is driven by a hydraulic motor 34 connected to one rotating shaft 2.

For example, the hydraulic motor 34 is connected to a variable discharge pump through a pair of hydraulic pipes to form a closed circuit and is driven. A brake relief valve, a negative pressure prevention check valve, a boost pump, and a boost pressure setting relief valve, which are common in closed circuit hydraulic drive systems, are connected between these hydraulic pipings, and an oil tank and suction filter are also connected between the hydraulic piping. and an electric motor, forming a hydraulic motor drive circuit with excellent responsiveness and efficiency.

Pressure oil port 1 attached to fixed piece 8 in rotating body 1
0 and 11, the pressure oil is sent from a hydraulic pump through a solenoid valve through the rotary coupling springs 35 and 35 connected to the end of the rotating shaft 2, and is used to adjust the solenoid valve. Therefore, the locking position of the movable side eccentric weight 5 of the rotating body 1 can be arbitrarily set and controlled, and the locking position can be mechanically limited and fixed by the above-mentioned stopper and link mechanism.

First, when the rotating body 1 is started, as mentioned above, the unbalanced weight position on the movable side is rotated 180° with respect to the fixed side, that is, at a fixed position that is axially symmetrical.
The excitation force is zero, the center of gravity of the rotating body is aligned with the rotating shaft 2, the minimum starting torque is required, and steady rotation can be achieved quickly. Next, when supplying pressure oil, it can be rotated to any position by selecting the pressure oil supply port and adjusting the supply amount, and the excitation force due to the rotation of the eccentric weights 4 and 5 is reduced. can get. Here, as the unbalanced weight part 5 of the rotating body 1 moves during rotation, the moment of inertia increases and the rotation speed decreases, but the hydraulic motor 3
It can be easily dealt with by controlling the drive system in 4.
It operates as a vibration damper for any excitation force controlled by a solenoid valve.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional front view of a rotating body according to the present invention, and FIG. 2 is an explanatory sectional view taken along the - line in FIG. 1. FIG. 3a is the same side view as FIG. 1, and FIG. 3b is a perspective explanatory view showing details of the engaging portion between the rotary arm and the stopper. FIG. 4 is a top view of the rotary vibration damping device according to the present invention. In the figure, 1...rotating body, 2...rotating shaft, 3...housing, 4, 5...unbalanced weight, 6...cover, 7
...Bolt, 8...Fixing piece, 9...Oil passage, 10,
11...Pressure oil port, 12...Rotating arm, 1
3, 16... bolt, 14 arm pin, 15...
Rack groove, 17...stopper, 18...fixing link, 19...pin, 20...spring, 30...
Pedestal, 31... Bearing, 32, 33... Gear, 34
...Hydraulic motor, 35...Rotary joint.

Claims (1)

[Scope of Claims] 1. In a rotary vibration damping device that generates vertical vibration by rotating a pair of rotating bodies having a pair of weights in opposite directions, a pair of eccentric weights having the same rotational moment within the rotating body. are arranged coaxially, one of the eccentric weights is fixed, and the other is rotatable in a cylindrical cavity separated in the rotational direction by a fixed piece with pressure oil ports on both sides, with the movable side being the fixed side. A rotary excitation type vibration damping device characterized in that the position of the eccentric weight on the movable side after being fixed is made variable by supplying pressure oil to both sides of the fixed piece with an axially symmetrical position as the fixed position. 2. In a rotary vibration damping device that generates vertical vibration by rotating a pair of rotary bodies having a pair of weights in opposite directions, a pair of unbalanced weights having the same rotational moment are placed coaxially within the rotor, One side of the eccentric weight is fixed, and the other is rotatable in a cylindrical cavity separated in the rotational direction by a fixed piece with pressure oil ports on both sides, and the movable side is positioned axially symmetrically with the fixed side. The position of the movable biased weight relative to the fixed side is variable by supplying pressure oil to both sides of the fixed piece, and the rotary arm has a pin at the tip and is fixed to a boss that protrudes outside the rotating body from the bearing of the movable biased weight. , a stopper that can be fixed at any position in the rotational direction of the rotary arm on the end face of the rotating body, and a pin for fixing that is pivoted on the stopper, one end is stretched with a spring, and the other end is held by the spring force when the pin is inserted. A rotary vibration damping device characterized in that a link mechanically maintains the position of an eccentric weight on a movable side.