JPH10132019A - Anti-rolling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep a desired phase relation between a movable mass and an object in the case that oscillation of the movable mass is suppressed at both ends of an orbit by arranging a resetting force generation device for generating the resetting force of the movable mass, and springs for stoppers on both ends of the orbit. SOLUTION: An anti-rolling device adapted to a gondola, etc., has a movable mass 21 freely movable along an orbit member 11, and a pair of support members 13A, 13B which support the orbit member 11 it its both ends. Two pairs of wheels 21A, 21B mounted on the movable mass 21 are engaged with orbit grooves 11A, 11B parallely formed on an upper surface 11. Springs 23A, 23B arranged on both sides of the movable mass 21 is installed on the support members 13A, 13B. Resetting force of the movable mass 21 is generated by elasticity of the springs 23A, 23B. Buffer rubbers 15A, 15B and springs 17A, 17B for stoppers are mounted on the support members 13A, 13B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-oscillation device for reducing the oscillation of an object to be reduced, and more particularly to a device for reducing the oscillation of an object to be reduced by a movable mass reciprocating on a track. The present invention relates to a dynamic vibration absorber type vibration reducing device. The object to be attenuated includes a suspended ship, a marine structure floating on the sea or water such as a purge, and a structure suspended in the air such as a lift and a gondola.

[0002]

2. Description of the Related Art Conventionally, as an anti-oscillation device for reducing the oscillation of an object to be reduced, an active type using an actuator and a passive type using a dynamic vibration absorber principle are known. The active type device is configured to detect the motion of the object to be reduced by a sensor and vibrate the movable mass by an actuator. The phase of the vibration of the movable mass is controlled so as to reduce the motion of the object to be reduced. Further, there is also a type in which a damping action is generated by using torque due to a gyro effect.

On the other hand, a passive device using the dynamic vibration absorber principle has a simpler structure because it does not use an actuator for driving a movable mass, and has a wide range of application because it does not consume power.

Referring to FIG. 3, an example of a conventional vibration damping device using the principle of a dynamic vibration absorber will be described. This rocking device includes a track member 11 serving as a bottom member, a movable mass 21 that can freely move along the track member 11, and a pair of support members 13A and 13B that support the track member 11 on both sides.

On the upper surface of the track member 11, a track 2 is formed.
The parallel track grooves 11A and 11B are provided. The movable mass 21 is provided with two pairs of wheels 21A and 21B. Wheels 21A and 21B are respectively provided with raceway grooves 11A and 1
1B.

Before and after the movable mass 21, springs 23A,
3B is mounted, and the other ends of the springs 23A, 23B are mounted on support members 13A, 13B. This spring 23A, 2
The restoring force of the movable mass 21 is generated by the elastic force of 3B. The object to be rocked is shaken and the movable mass 21 is moved to the track member 11.
, The springs 23A and 23B are biased.
The movable mass 21 reciprocates, that is, vibrates along the track member 11 by the restoring force of the springs 23A and 23B.

[0007] The shock absorbers 14A, 14B and the buffer rubber 15 are attached to the support members 13A, 13B on both sides.
A and 15B are mounted. The shock absorbers 14A and 14B and the buffer rubbers 15A and 15B are configured to absorb the impact of the movable mass 21.

[0008]

Generally, in order for an anti-oscillation device to generate an optimum anti-oscillation effect on an object to be reduced, the period of the vibration of the movable mass 21 and the period of the oscillation of the object to be reduced are generally required. Must be equal and a predetermined phase difference exists between the two vibrations.

For example, when the rocking angle of the object to be reduced is large and the movable mass 21 collides with the shock absorbers 14A and 14B at both ends, the phase relationship between the two deteriorates, and the desired rocking action cannot be obtained. Therefore, usually, the amplitude of the reciprocating motion (vibration) of the movable mass 21 is set or designed so that the movable mass 21 does not collide with the shock absorbers 14A, 14B.

The phase relationship between the movable mass 21 and the object to be reduced will be described with reference to FIG. A curve 401 in FIG. 4A represents the vibration of the movable mass 21 assuming that the track member 11 is infinitely long. The movable mass 21 can move freely without colliding with the shock absorbers 14A, 14B even if the amplitude of the vibration is large. Therefore, the reciprocating motion of the movable mass 21 is represented by a sinusoidal curve.

A curve 402 in FIG. 4B represents the vibration of the object to be reduced. As is clear from the comparison between the curves 401 and 402, the cycle of the vibration of the movable mass 21 and the cycle of the oscillation of the object to be attenuated coincide with each other, and the phase of the movable mass 21 is delayed by 90 ° from the phase of the object to be attenuated. I have.

However, in practice, the length of the track member 11 is finite, and the movable mass 21 collides with the shock absorbers 14A and 14B, and the reciprocating motion thereof is restricted.
The path length L _S = 2A _S where the movable mass 21 can actually move is smaller than the original path length L = 2A of the movable mass 21.

[0013]

## EQU1 ## L _S <L

In this case, the movement of the movable mass 21 is a curve in which the sine wave is deformed as shown by a curve 403 in FIG. 4A. This curve 403 is a vibration having a phase difference smaller than 90 ° with respect to the phase of the object to be reduced, as shown in the figure.

Thus, when the movable mass 21 collides with the shock absorbers 14A and 14B, the desired phase relationship between the movable mass 21 and the object to be reduced, in this example, the phase difference is 90%.
° is deteriorated, and the anti-oscillation effect on the object to be anti-oscillation is reduced.

In the above-described example, the shock absorbers 14A, 14B and the buffer rubbers 15A, 15B for absorbing the impact of the movable mass 21 are provided, but the shock absorbers 14A, 14B and the buffer rubber 15A,
The same applies to the case where 15B is not provided. In addition, movable mass 2
A damper for giving a damping force to the first movement may be provided.

In view of the above, according to the present invention, even when the swing angle of the object to be reduced is large and the movable mass 21 collides with the shock absorbers 14A and 14B at both ends of the track, the movable mass 21 and the object to be reduced It is an object of the present invention to provide a rocking device configured to be able to reduce deterioration of a desired phase relationship between objects.

In view of the above, the present invention provides a method for controlling the distance between the movable mass 21 and the object to be reduced even when the swing angle of the object to be reduced is large and the vibration of the movable mass 21 is restricted at both ends of the track. It is an object of the present invention to provide a vibration reduction device configured to maintain a desired phase relationship.

[0019]

According to the present invention, a movable mass capable of reciprocating along a predetermined trajectory, a restoring force generating device for generating a restoring force of the movable mass, and a trajectory of the trajectory are provided. A stopper spring provided at both ends, and the kinetic energy of the movable mass is accumulated by the stopper spring.

According to the vibration reducing device of the present invention, the restoring force generating device is configured to include a spring connected to the movable mass. Buffer rubbers are provided at both ends of the track. Further, a damper for generating the damping force of the movable mass is provided.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, an example of a vibration damping device using the dynamic vibration absorber principle according to the present invention will be described. This rocking device includes a track member 11 serving as a bottom member, a movable mass 21 that can freely move along the track member 11, and a pair of support members 13A and 13B that support the track member 11 on both sides.
The movable mass 21 is provided with two pairs of wheels 21A and 21B.

A track 2 is formed on the upper surface of the track member 11.
The parallel track grooves 11A and 11B are provided. The movable mass 21 is provided with two pairs of wheels 21A and 21B. Wheels 21A and 21B are respectively provided with raceway grooves 11A and 1
1B.

Before and after the movable mass 21, springs 23A,
3B is mounted, and the other ends of the springs 23A, 23B are mounted on support members 13A, 13B. This spring 23A, 2
The restoring force of the movable mass 21 is generated by the elastic force of 3B. The object to be rocked is shaken and the movable mass 21 is moved to the track member 11.
, The springs 23A and 23B are biased.
The movable mass 21 reciprocates, that is, vibrates along the track member 11 by the restoring force of the springs 23A and 23B.

The support members 13A and 13B on both sides are provided with buffer rubbers 15A and 15B and stopper springs 17A and 1
7B is mounted. The anti-shock device of this embodiment is different from the conventional anti-shock device shown in FIG.
The difference is that stopper springs 17A and 17B are provided instead of A and 14B, and the other configurations may be the same.

Referring to FIG. 2, the function of the stopper springs 17A and 17B provided in the rocking device according to the present invention will be described. The stopper springs 17A and 17B have a large swing angle of the object to be reduced, and the original amplitude A of the vibration of the movable mass 21 is equal to the path length L _{S of the} movable mass 21 that can actually move.
It functions to maintain a desired phase relationship between the movable mass 21 and the object to be reduced even when the vibration of the movable mass 21 is limited.

FIG. 2 is a diagram showing the phase relationship between the movable mass 21 and the object to be reduced, similar to FIG. Curve 4 of FIG. 2A
01 is the same as curve 401 in FIG.
2B represents the vibration of the movable mass 21 when it is assumed that 1 is infinitely long. The curve 402 in FIG. 2B is the same as the curve 402 in FIG. The cycle of vibration of the movable mass 21 and the cycle of oscillation of the object to be reduced are the same, and the phase of the movable mass 21 is delayed by 90 ° from the phase of the object to be reduced.

The curve 405 in FIG. 2A shows that the length of the track member 11 is finite and the movable mass 21 is
A represents the vibration of the movable mass 21 when it collides with A and 17B. When the rocking angle of the object to be reduced is large and the movable mass 21 collides with the stopper springs 17A and 17B on both sides, the movement of the movable mass 21 becomes a curve in which a sine wave is deformed, but the curve 401 or the curve 403 ( Compared with FIG. 4), the phase change, that is, the phase delay is extremely small. That is, the vibration of the movable mass 21 maintains a phase difference of about 90 ° with respect to the phase of the object to be reduced.

The movable mass 21 includes stopper springs 17A, 1
When the stopper springs 17A and 17B contract when contacting the stopper 7B, the kinetic energy of the movable mass 21 is converted into elastic energy of the stopper springs 17A and 17B and stored. When the amount of contraction of the stopper springs 17A, 17B becomes maximum, the direction of movement of the movable mass 21 is reversed, and the stopper springs 17A, 17B begin to expand. The elastic energy stored in the stopper springs 17A and 17B is converted into kinetic energy of the movable mass 21.

The movable mass 21 includes a stopper spring 17A,
When the amount of contraction and elongation of 17B becomes maximum, the direction of movement is reversed. Since the time point of the reversal of the movement direction is delayed as compared with the case of colliding with the shock absorbers 14A and 14B, the phase relationship with respect to the object to be reduced is maintained.

Accordingly, the stopper springs 17A, 17B
Is designed to absorb the kinetic energy (１ ／) mv ² of the movable mass 21. The motion of the movable mass 21 is expressed as follows.

[0031]

[Number 2] _{X = Asinω n t v = dX} / dt = Aωcosω n t

Here, ω _n is the angular velocity of the vibration of the movable mass 21. The elastic energy E stored in the stopper springs 17A and 17B is determined by the spring constant k and the amount of deformation x of the spring.

[0033]

E = (1/2) kx ² = (1/2) mv ²

When the spring constant k is increased, the amount of deformation x of the spring is reduced, and the path length L _S of the movable mass 21 that can actually move is increased, which is convenient. However, when the rigidity is increased by increasing the spring constant k, an impact is generated when the movable mass 21 abuts against the stopper springs 17A, 17B, and the result is similar to that of a collision with a rigid body.

Conversely, when the spring constant is reduced, the amount of deformation x of the spring increases, and the path length L _{S of} the movable mass 21 that can actually move is reduced, which is inconvenient. However,
Even if the movable mass 21 abuts against the stopper springs 17A, 17B, no impact is generated. With these in mind,
The stopper springs 17A and 17B are designed.

In the above-described example, the shock absorbers 14A, 14B and the buffer rubbers 15A, 15B for absorbing the impact of the movable mass 21 are provided, but the shock absorbers 14A, 14B and the buffer rubber are provided. Fifteen
The same applies to the case where A and 15B are not provided. Further, a damper for providing a damping force to the movement of the movable mass 21 may be provided.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to these examples, and various modifications can be made within the scope of the invention described in the claims. It will be understood by those skilled in the art.

[0038]

According to the present invention, since the kinetic energy of the movable mass is absorbed and released by the stopper spring, the movable mass and the object to be reduced maintain a desired phase relationship. Has the advantage that

According to the present invention, even when the swing angle of the object to be attenuated is large, the desired phase relationship between the movable mass and the object to be attenuated can be maintained. It has the advantage that a damping effect can be achieved.

According to the present invention, the desired phase relationship between the movable mass and the object to be reduced is maintained by a relatively simple device even if the swing angle of the object to be reduced is large. Has the advantage that an optimal anti-rolling effect can be achieved.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration example of a rocking device according to the present invention.

FIG. 2 is an explanatory diagram for explaining a phase relationship between a movable mass of the rocking device according to the present invention and a rocking target.

FIG. 3 is a diagram showing a configuration example of a conventional rocking device.

FIG. 4 is an explanatory diagram for explaining a phase relationship between a movable mass of a conventional rocking device and a rocking target.

[Explanation of symbols]

 11 Track member (bottom member) 11A, 11B Track groove 13A, 13B Support member 14A, 14B Shock absorber 15A, 15B Buffer rubber 17A, 17B Spring for stopper 21 Movable mass 21A, 21B Wheel 23A, 23B Spring

Claims (4)

[Claims] A movable mass capable of reciprocating along a predetermined trajectory, a restoring force generator for generating a restoring force of the movable mass, and stopper springs provided at both ends of the trajectory; A vibration reducing device, wherein the kinetic energy of the movable mass is stored by the stopper spring. 2. The rocking device according to claim 1, wherein said restoring force generating device includes a spring connected to said movable mass. 3. The vibration reducing device according to claim 1, wherein buffer rubbers are provided at both ends of the track. 4. The vibration reducing device according to claim 1, further comprising a damper for generating a damping force of the movable mass.