JPH0157204B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vibration control device for reducing low frequency vibrations of structures such as road bridges and railway bridges.

For convenience, the explanation will be given below using a traffic bridge as an example.

Generally, a traffic bridge has a structure in which a bridge 1 is supported at both ends by piers 2, as shown in FIG. In this type of traffic bridge, as the number of vehicles running on the traffic bridge increases and the traveling speed increases, excessive external force is applied to the traffic bridge. Coupled with the decrease in bending stiffness, extremely large vibrations are induced in traffic bridges. Depending on the situation, vibrations from bridges can generate air pressure vibrations in the atmosphere, which become low-frequency sound pressure waves, usually below 30 Hz, that propagate to the surrounding area, and manifest as so-called low-frequency pollution. There are cases. Furthermore, the propagation of vibrations in the ground loosens nearby buildings and residences, causing shutters, glass doors, etc. to rattle and vibrate. Alternatively, the vibrations of houses themselves can cause vibration pollution, causing great discomfort to residents.

Conventionally, countermeasures for the vibration of traffic bridges include improving and changing the vibration properties of traffic bridges, such as increasing the rigidity by reinforcing bridges and piers, or adding auxiliary piers to increase the number of support points on the bridge. In order to insulate the low-frequency sound pressure itself that propagates into the atmosphere, they installed soundproof walls, covers, etc. in an effort to reduce the discomfort caused to residents.

However, the reality is that such conventional measures have not achieved sufficient vibration and noise reduction effects.In addition, installing auxiliary piers on existing traffic bridges, reinforcing bridges, etc. requires the use of land space. However, there were disadvantages such as physical constraints and construction problems.

The present invention is fundamentally different from the conventional vibration reduction measures as described above, and by actively applying vibration control force to the structure according to its vibration characteristics, the present invention reduces the vibration of the structure. The present invention relates to a vibration control device that reduces vibration and improves its vibration properties.

FIG. 2 shows a conceptual diagram of a control force block of a system to which the present invention is applied. 3 is a traffic road bridge vibration system to be subjected to vibration reduction, 4 is a vibration detector attached to the bridge 1 of the traffic road, 5 is a control circuit, and 6 is a drive device that generates control force.

With such a configuration, the physical quantity of vibration (displacement, velocity acceleration) of the traffic road bridge is measured by the detector 4,
A control force corresponding to this vibration is generated from the drive device 6 via the control circuit 5 and applied to the traffic road bridge 3,
To achieve vibration reduction of traffic road bridge 3.

The present invention relates to the drive device 6 of the vibration control device having the above configuration, and is one of the linear electromagnetic actuators (hereinafter appropriately referred to as linear electric devices) that can be adopted in the present invention.
An example is shown in FIG. In FIG. 3, 11 is a connecting rod, 31 is a coil holder, 32 is a coil, 33 is an excitation yoke, 34 is an excitation electromagnet, and 35 is a magnetic steel or permanent magnet.

A magnetic flux Φ generated by the excitation electromagnet 34 interlinks with the coil 32 as shown by the broken line in FIG. Here, the magnetic steel or permanent magnet 35 provided at the end of the excitation yoke 33 utilizes or increases the magnetic flux Φ more effectively. That is, in this configuration, the coil 3
Although the second part of the magnetic flux is generated by a permanent magnet, it is not limited to this configuration.

An embodiment of the present invention is shown in FIG. In Fig. 4, 1 is a bridge, 2 is a pier, 10 is an arm attached to bridge 1, 12 is a linear electric device, and 1
An example has a configuration as shown in FIG. 3, where 11 indicates a connecting rod.

By using the push/pull force of the linear electrical equipment 12 to expand and contract the span l between the tips of two connecting rods attached to it, a moment is applied to the bridge 1 and the control force required for vibration control is obtained.
Further, the push/pull force can be adjusted by changing the voltage applied to the coil shown in FIG. 3, and can be easily incorporated into the system shown in FIG. 2.

In the above embodiment, the arms are attached to both ends of the traffic bridge, and the other ends of the arms are connected to each other using linear electrical equipment and connecting rods. It can also be applied to antennas, floors, and other structures by devising a mounting method.

As described above, according to the present invention, since a linear electromagnetic actuator that generates a control force in the axial direction along the longitudinal direction of the connecting rod is used, it is possible to apply a restraining moment to the target structure. ,
It has the effect of reducing vibration.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a general traffic bridge, FIG. 2 is a block diagram showing the control system of the present invention, FIG. 3 is a structural diagram showing an example of linear electric equipment that can be adopted in the present invention, and FIG. The figure is a configuration diagram showing an embodiment in which a linear electric device according to the present invention is attached to a traffic bridge. In the figure, 1... Bridge, 2... Pier, 3...
Bridge vibration system, 4...Detector, 5...Control circuit, 6
... Drive equipment, 10 ... Arm, 11 ... Connection rod, 12 ... Linear electrical equipment, 31 ... Coil holder, 32 ... Coil, 33 ... Excitation yoke, 3
4...Exciting electromagnet. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1 Vibration control in which an actuator is installed on a target structure that generates vibrations in response to an external force, a mechanical physical quantity of the target structure is detected by a sensor, and a control force is generated in the actuator based on the mechanical physical quantity. In the apparatus, a pair of arms coupled to the target structure at a predetermined interval;
These arms are each provided with a connecting rod having a longitudinal direction, one end of which is connected to each other, and the actuator is provided between the other ends of these connecting rods, and generates the control force in the longitudinal direction of the connecting rod. A vibration control device characterized by a linear electromagnetic actuator.