JPH0314092B2 - - 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 vibration damping devices that are installed on a ship's hull to reduce ship vibration, the present invention provides a system that allows the vibration frequency and excitation force applied to the ship's hull to be freely changed during operation.
Moreover, the purpose 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 furthermore, a rotary vibration damping device that is simple in structure, easy to operate, and inexpensive. It is an object.

Structure and Effects of the Invention The present invention provides a rotary vibration damping device that generates vertical vibration by rotating a pair of rotating bodies having weights in opposite directions. Unbalanced weights are arranged on the same axis, one of the unbalanced weights is fixed, and the other has a gear on the side that contacts the fixed side unbalanced weight, and is driven by the drive gear of the hydraulic motor placed on the fixed side unbalanced weight. The movable weight is rotatable with respect to the fixed weight, and the position of the movable weight with respect to the fixed weight is variable by driving a hydraulic motor, with the axially symmetrical position of the movable weight and the fixed weight being zero moment position. This is a rotary vibration damping device.

In the rotary excitation type vibration damping device according to the present invention, the rotating body has a pair of eccentric weights, and the rotational position of the movable eccentric weight with respect to the fixed side eccentric weight can be freely varied by driving a hydraulic motor. The excitation force is obtained by multiplying the sum of the product of the mass of each unbalanced weight and the distance from the axis to each unbalanced weight by the square of the angular velocity, and the excitation force is obtained by changing the center of gravity position of the unbalanced weight can be set freely.

When the rotating body is started, the excitation force is 0 because the movable side unbalanced weight position is combined with the fixed side unbalanced weight position and the rotating body is in a 180° rotation position, that is, an axially symmetrical position (zero rotational moment position). , does not require large driving torque, and has excellent rotation start-up performance at startup.
It has the advantage of good responsiveness.

In addition, the center of gravity of the eccentric weight can be moved by driving and holding a hydraulic motor, or it can be held mechanically by a stopper and link that can be set at any position after operation, making it simple and easy to control. It is cheap in comparison.

Disclosure of the Invention Based on Drawings An example of the configuration of a rotating body will be described below based on drawings. FIG. 2 is a side view of the rotating body according to the present invention, FIG. 3 is a longitudinal sectional front view of the rotating body according to the present invention, and FIG. 4 is an explanatory cross-sectional view taken along the line - in FIG. 2. FIG. 5 is an explanatory cross-sectional view taken along the same line.

The rotating body 1 is in contact with a substantially semi-cylindrical fixed side biased weight 5 whose one end is fixed to the rotating shaft 2 by a key 3 and a ring stopper 4, and a disk portion surface at the other end of the stationary side biased weight 5, It is composed of a movable side biased weight 6 which is rotatable on the rotary shaft 2 via a metal 7, and whose other end is fixed in the axial direction by a ring stopper 4 to serve as a substantially semi-cylindrical movable side biased weight.

On the side of the movable biased weight 6 that contacts the fixed biased weight 5, a contact end 8 is provided protruding from the shaft center side thereof.
A driven gear 9 is fixed to the outer periphery of this contact end 8.

In addition, a hydraulic motor 10 is mounted in the axial direction in a recess in the center of the fixed side eccentric weight 5, and a small-diameter drive gear 11 is pivotally supported by a metal on the disc part of the fixed side eccentric weight 5. The drive gear 11 is a hydraulic motor 10
The drive gear 11 meshes with the driven gear 9, and the movable biased weight 6 is rotated via the drive gear 11 by the rotational drive of the hydraulic motor 10. This is a configuration that allows

In addition, a fixed piece 12 is located above the perpendicular line of the disc surface of the fixed side eccentric weight 5, which is on the right side in the horizontal direction in FIG.
is bolted, and the movable biased weight 6 is at a position axially symmetrical to the center of gravity of the stationary biased weight 5, and also collides with this fixed piece 12 during rotation.

The fixed side unbalanced weight 5 and the movable side unbalanced weight 6 are shown in Figure 2.
In the position shown in FIG. 3, the movable weight 6 is in an axially symmetrical position with respect to the fixed weight 5, and the dimensions and weights of both are set so that the moment due to the rotational force of the rotating body 1 is 0. There is.

By driving and holding the hydraulic motor 10, the movable unbalanced weight 6 can be rotated to an arbitrary position and held at the same position, but the rotational position of the movable unbalanced weight 6 relative to the fixed side unbalanced weight 5 can be maintained. It is also good to do it mechanically.

For example, as shown in FIGS. 2 and 5, various radial changes are made on the disk surface so that a stopper 13 having the same shape as the fixed piece 12 can be fixed to the disk surface of the stationary biased weight 5 with bolts. A bolt hole 14 is drilled at the position, and a locking rib 15 is provided protruding from the upper end of the surface of the stopper 13 facing the end surface of the movable side eccentric weight 6.
On the movable side biased weight 6 side, a locking link 16 is pivotally supported on the upper part of the rotor end surface with a pin such that its tip protrudes from the rotor end surface, and one end is attached to the spring 1.
A locking groove 18 is provided on the lower surface of this tip, and the movable biased weight 6 rotates and hits the stopper 13 fixed at a predetermined position. When stopping, the locking groove 18 may be fitted into the rib 15 of the stopper 13, and the movable biased weight 6 may be mechanically held at a predetermined position. To disengage the locking link 16, rotate the movable biased weight 6 toward the home position, and the locking link 16 will be released against the force of the spring 17.
tilts backward and is released from the rib 15.

As described in detail, the rotating body according to the present invention can be started with a minimum driving force by starting rotation of the rotating shaft when the center of gravity of each eccentric weight is located 180° axially symmetrical, and the rotating body can be started with a minimum driving force. When the body is in steady operation, it can be rotated to any position by driving the hydraulic motor, and a rotational moment corresponding to the position of the movable biased weight can be obtained, so that the excitation force as a vibration damping device can be appropriately selected. Furthermore, the limit of the excitation force can be set freely by appropriately selecting the position of the stopper installed on the disk portion of the fixed side eccentric weight.

Embodiment An embodiment of the rotary vibration damping device according to the present invention will be described below. The first 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 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. It has a configuration in which a pair of meshing gears 32, 32 rotate in opposite directions, 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.

The configuration for supplying pressure oil to the hydraulic motor 10 attached to the fixed side biased weight 5 of the rotating body 1 is, for example, a hydraulic pump connected to rotary joints 35, 35 connected to the ends of the rotating shaft 2 via a solenoid valve. is sent through the rotating shaft 2 and through the piping 36, and the locking position of the movable side eccentric weight 6 of the rotating body 1 is arbitrarily set and controlled by adjusting a solenoid valve. It is configured so that it can be mechanically limited and fixed by a link mechanism.

First, when starting the rotating body 1, as described above, the movable side unbalanced weight position, that is, the position of the movable side unbalanced weight 6, is at a fixed position of an axially symmetrical position of 180° rotation with respect to the fixed side unbalanced weight 5. Therefore, the excitation force is 0,
The center of gravity of the rotating body coincides with the rotation axis 2, the minimum starting torque is required, and steady rotation can be achieved quickly. Next, the fixed side biased weight 5
By adjusting the amount of pressure oil supplied to the hydraulic motor 10, the movable eccentric weight 6 can be rotated to an arbitrary position, and an excitation force can be obtained by rotating the pair of eccentric weights. Here, as the movable side eccentric weight 6 of the rotating body 1 moves during rotation, the moment of inertia increases and the rotation speed decreases, but this can be easily countered by controlling the drive system of the hydraulic motor 34, and the solenoid Acts as a damper for any excitation force controlled by a valve.

[Brief explanation of the drawing]

FIG. 1 is a top view of a rotary vibration damping device according to the present invention. FIG. 2 is a side view of the rotating body according to the present invention, FIG. 3 is a longitudinal sectional front view of the rotating body according to the present invention, and FIG. 4 is an explanatory cross-sectional view taken along the line - in FIG. 2. FIG. 5 is an explanatory cross-sectional view taken along the same line. In the figure, 1... Rotating body, 2... Rotating shaft, 3... Key, 4... Ring stopper, 5... Fixed side biased weight, 6... Movable side biased weight, 7... Metal, 8...
Contact end, 9...driven gear, 10...hydraulic motor,
11... Drive gear, 12... Fixed piece, 13... Stopper, 14... Bolt hole, 15... Rib, 16
... Locking link, 17 ... Spring, 18 ...
...Latching groove, 30...Pedestal, 31...Bearing, 32,
33...Gear, 34...Hydraulic motor, 35...Rotary joint, 36...Piping.

Claims (1)

[Claims] 1. In a rotary vibration damping device that generates vibration in the vertical direction by rotating a rotating body having a pair of weights in opposite directions, a pair of unbalanced weights having the same rotational moment are placed coaxially within the rotating body. , one of the unbalanced weights is fixed, the other has a gear on the side that contacts the fixed side unbalanced weight, and is rotatable by being driven by a drive gear of a hydraulic motor placed on the fixed side unbalanced weight, A rotary vibration extinguisher characterized in that the axially symmetrical position of the movable side unbalanced weight and the fixed side unbalanced weight is the rotational moment zero position, and the position of the movable side unbalanced weight with respect to the fixed side unbalanced weight is made variable by driving a hydraulic motor. Shaking device.