JP6979800B2 - Wind lock mechanism - Google Patents

Description

The present invention relates to a wind lock mechanism provided in the seismic isolation layer of a building together with a seismic isolation device and for restraining and controlling the displacement of the seismic isolation device in a strong wind.

For example, when a medium-to-high-rise building receives a huge earthquake, the weakest layer of the building is damaged and its bearing capacity begins to decrease, seismic energy (vibration energy) concentrates on this layer, causing layer collapse, and the other layers are sound. Even though the energy is secured, the phenomenon that the building collapses due to the layer collapse mode occurs. In addition, even if the collapse does not occur, the damage to the weakest layer will be enormous, and it will be difficult to recover by repair.

On the other hand, as is well known, in buildings such as office buildings, public facilities, and apartment buildings, seismic isolation such as laminated rubber is used for the seismic isolation layer between the upper structure and the lower structure, such as between the building body and the foundation. In the event of an earthquake, the natural period of the superstructure is shifted from the predominant period band of the seismic isolation to the long period side by interposing a device, and the response acceleration is reduced to suppress the shaking.

On the other hand, in a seismic isolated building equipped with a seismic isolation layer, the effect of reducing the response during an earthquake can be obtained as the rigidity of the seismic isolation layer is made as small as possible and the period is lengthened. If the seismic isolation layer is too soft), the building will easily shake due to the wind load, such as during strong winds.

For this reason, in normal seismic isolation buildings / seismic isolation designs, seismic isolation devices made of laminated rubber with lead plugs are used, and lead dampers and steel dampers are used in combination with seismic isolation devices made of natural rubber laminated rubber. By making the yield strength larger than the wind load acting on the seismic isolation layer, shaking during strong winds is avoided.

However, measures to increase the yield strength of the seismic isolation layer by using laminated rubber with lead plugs or by using a damper together with the seismic isolation device naturally means increasing the equivalent rigidity of the seismic isolated building. Since it contradicts the lengthening of the period, the effect of reducing the response during an earthquake is reduced.

Against this background, in order to prevent the seismic isolation layer from being deformed during strong winds (or small and medium-sized earthquakes), to prevent the equivalent rigidity from becoming too large, and to prevent the effect of reducing the response during large earthquakes due to the long period from being impaired. The wind lock mechanism has been proposed and put into practical use.

Specifically, when a set load larger than the wind load acts, a mechanism that concludes the substructure and the superstructure of the seismic isolated building with a shear pin that breaks due to shearing force and restrains the movement of the superstructure when the wind load acts (by the shear pin). Wind lock mechanism), a sensor that detects external forces such as wind and earthquakes, and actively controls the damping coefficient of the oil damper according to the magnitude of the external force (active control type oil damper with wind lock mechanism), approaching a typhoon / A shear pin (lock pin) that is manually inserted and removed according to passage or the like is provided in the oil damper (an oil damper with a passive wind lock mechanism) and the like has been proposed and put into practical use (see, for example, Patent Document 1).

In addition, the electric power generated by the wind turbine installed on the building pulls up the steel suction plate with an electromagnet to attract and integrate it, and the annular reinforcing steel plate of the locking hole provided in the lower structure comes into contact with the steel suction plate. Therefore, there is also a structure in which the superstructure to be seismically isolated is locked (moving restraint) when a wind load is applied (see, for example, Patent Document 2).

Further, a damper having a variable resistance using an MR fluid (ferrofluid fluid) has been put into practical use (see, for example, Non-Patent Document 1). This is a device that utilizes the characteristics of MR fluid whose viscous resistance changes when a magnetic field is applied to the fluid from the outside. By increasing the current flowing through the coil, it is possible to apply damping force that does not depend on displacement, similar to frictional resistance. There is a feature.

Japanese Unexamined Patent Publication No. 2004-176525 Japanese Unexamined Patent Publication No. 2006-23701

Hideko Sato, Takashi Fujita: Semi-active seismic isolation structure using MR fluid damper, Production Research 67, 2005

However, the wind locking mechanism using shear pins (and the oil damper with a passive wind locking mechanism) has an initial rigidity that is extremely close to rigidity until the lock load is reached.

For this reason, for ground motion input accelerations such as small and medium-sized earthquakes that act below the lock load, that is, within the range where the lock is not released, the acceleration is directly transmitted to the upper building side via the mechanism, compared to the case without the wind lock mechanism. There were cases where the response was increased. In addition, even in the case of a large earthquake, the acceleration is directly transmitted until the lock is released, so that the response tends to increase especially on the floor directly above where the device is installed and on several layers above it.

Furthermore, in the wind lock mechanism using shear pins, the load is momentarily released when the lock is released due to shear failure of the shear pins, so that load is transmitted to the superstructure side of the building as an impact load, and the response acceleration is instantaneous. There is a problem of getting bigger. There is also the problem that sheapin is very expensive.

In the oil damper with a passive wind lock mechanism, it is necessary to install and release the shear pin (lock pin) before the wind becomes a problem, and there remains a question as to whether this work can be done without fail.

In the oil damper with an active control type wind lock mechanism, the wind lock function is not exhibited at all in the unlikely event of failure. Therefore, from the viewpoint of long-term durability and reliability of electrical parts, it is necessary to design in a fail-safe state in which it does not operate in case of failure.

Even in the lock mechanism configured to control the movement restraint by the electric power generated by the wind turbine, the attractive force of the electromagnet is small in the amount of wind power generation when the superstructure to be seismically isolated starts to be displaced by the wind, and the building is constructed by this mechanism. It is difficult to move and restrain. In addition, there is a problem that the positions of the electromagnet and the steel suction plate are displaced if the building is moved and then sucked.

Further, in the damper whose resistance is variable by using the MR fluid (ferrofluid fluid) disclosed in Non-Patent Document 1, although it has a simple structure, the reaction force is small with respect to the dimensions of the damper, and it is used for construction. It is difficult to put it to practical use.

In view of the above circumstances, the present invention preferably controls the movement of the lower structure and the upper structure at the time of wind load, and cancels the movement control state at the time of an earthquake to exert the seismic isolation effect more reliably and effectively than before. It is intended to provide a wind locking mechanism that enables.

In order to achieve the above object, the present invention provides the following means.

The wind lock mechanism of the present invention is provided in parallel with the seismic isolation device in the seismic isolation layer between the upper structure and the lower structure, and one end is connected to the upper structure and the other end is connected to the lower structure to be horizontally arranged. When a relative displacement occurs between the upper structure and the lower structure, electric current is generated according to the magnitude of the wind acting on the MR damper device to which the axial force is input and the upper structure, and according to the magnitude of the wind. The MR resistance unit is provided with a wind power generation unit that supplies the generated power to the coil of the MR resistance unit provided in the MR damper device, and the magnetic field of the MR resistance unit changes depending on the magnitude of the DC current value energized in the coil. The MR damper device is connected to the MR resistance section and the MR resistance section, and converts the axial displacement due to the axial force into rotation to convert the MR resistance section into rotation. It is characterized by comprising a ball screw mechanism in which a reaction force is applied by converting the resistance torque of the MR resistance portion with respect to the rotation into an axial force .
Further, in the wind locking mechanism of the present invention, the resistance force of the MR resistance portion is increased by elastic deformation until a predetermined shear deformation occurs in the MR resistance portion, and after the predetermined shear deformation is exceeded, a constant history is reached. It becomes a characteristic and may be almost 0 when the wind does not blow.

According to the wind lock mechanism of the present invention, by providing the seismic isolation layer between the superstructure and the substructure, the superstructure can be automatically restrained or released without using external power, and when the wind load is applied, the superstructure can be automatically restrained or released. It is possible to control the movement of the superstructure and the substructure, release the movement control state in the event of an earthquake, and exert the seismic isolation effect on the superstructure more reliably and effectively than before.

It is a figure which shows the wind lock mechanism which concerns on one Embodiment of this invention. It is a figure which shows the MR damper apparatus provided with the MR resistance part of the wind lock mechanism which concerns on one Embodiment of this invention. It is a figure which shows the S1 part and S2 part of FIG. It is a model diagram of the MR damper apparatus which concerns on one Embodiment of this invention. (A) is a figure which shows the MR damper apparatus provided with the MR resistance part of the wind lock mechanism which concerns on one Embodiment of this invention, (b) is the X1-X1 line arrow view of (a).

Hereinafter, the wind locking mechanism according to the embodiment of the present invention will be described with reference to FIGS. 1 to 5.

The wind locking mechanism A of the present embodiment includes an MR resistance unit 1 and a wind power generation unit 2 which are magnetic field forming means, and as shown in FIG. 1, a superstructure T1 and a substructure T2 such as between a building body and a foundation. An MR resistance unit 1 is provided in parallel with a seismic isolation device 4 such as laminated rubber on the seismic isolation layer 3 between the two, and a wind power generation unit 2 is provided on the top of the superstructure T1. It is not necessary to limit the installation position of the wind power generation unit 2.

The wind lock mechanism A of the present embodiment configured in this way moves and restrains the seismic isolation layer 3 so as not to be deformed by a wind load, that is, to prevent the superstructure T1 from being displaced relative to the substructure T2 in a strong wind. At the same time, the seismic isolation performance of the superstructure T1 by the seismic isolation device is exhibited in the event of a large earthquake. That is, in the event of a large earthquake, the response of the superstructure T1 is reduced while the period is long.

On the other hand, in the present embodiment, as shown in FIGS. 2 to 4, the MR resistance portion 1 of the wind lock mechanism A is used in a conventional viscous damper (for example, a viscous damper device such as a “damping frame” using a ball screw mechanism). The MR resistor (R) is provided in parallel with the viscous damping (C) to form the MR damper device 5.

As shown in FIGS. 2 and 3, the MR damper device 5 of the present embodiment has a ball screw mechanism 9 including a ball screw shaft 7 and a ball nut 8 inside a casing (support frame / cylinder) 6 forming an outer shell. Is incorporated, the ball screw shaft 7 is supported on the casing 6 in the axial direction O1 via a linear slider mechanism so as to be rotatable and non-rotatable, and the ball nut 8 is supported in the casing 6 in the axial direction O1 so as to be non-displaceable and rotatable. It is configured to be supported by.

Further, one end (upper end) of the casing 6 and one end (lower end) of the ball screw shaft 7 on the other end side are connected to the upper upper structure T1 and the lower lower structure T2 with the seismic isolation layer 3 of the building interposed therebetween. The damper device 5 is installed in the seismic isolation layer 3.

As a result, when a relative displacement occurs between the upper structure T1 and the lower structure T2 connecting one end of the casing 6 and one end of the ball screw shaft 7, an axial force is input to the MR damper device 5 and the ball screw shaft 7 is moved to the casing 6. On the other hand, the ball nut 8 is displaced in the axial direction O1 and rotates.

In the present embodiment, the axial O1 displacement is thus converted into the rotation of the ball nut 8 and transmitted to the MR resistance portion 1 of the wind lock mechanism A.

The MR resistance portion 1 which is the main body of the wind lock mechanism A is connected to the ball nut 8 via the inner cylinder 10 and rotates with the ball nut 8 via the rotating disk 11 and the casing 6 via the outer cylinder 12. A fixed disk 13 that is connected and installed non-rotatably and is laminated coaxially with the rotating disk 11, an MR fluid composite 14 sandwiched between the rotating disk 11 and the fixed disk 13, and an MR fluid. The composite 14 is provided with a coil 12a for applying a variable magnetic field.

The MR fluid composite 14 is configured by impregnating a porous material such as a sponge or a non-woven fabric with an MR fluid, and can effectively prevent sedimentation of ferromagnetic particles, which is a concern when the MR fluid is used alone as a hydraulic oil or the like. It is configured as follows.

In the MR fluid composite 14, clusters of ferromagnetic particles formed by applying a magnetic field are supported by fibers of a porous material, and exhibit a higher MR effect than in the case of a single MR fluid. Further, the magnetic field applied to the MR fluid composite changes in magnitude according to the magnitude of the DC current value energized in the coil 12a. That is, the shear resistance generated in the MR fluid composite increases as the applied magnetic flux density increases.

In the present embodiment, such an MR fluid composite 14 is formed in the shape of an annular disk like the rotating disk 11 and the fixed disk 13, and the plurality of rotating disks 11 and the fixed disk 13 are alternately stacked and arranged in the axial direction O1. The MR resistance unit 1 is configured by sandwiching them between the two.

The shear resistance force of the MR fluid composite 14 exhibits almost the same characteristics as that of the friction damper, and increases with strain due to elastic deformation until the MR fluid composite 14 undergoes a predetermined shear deformation. After that, slippage occurs at the interface with the fixed disk 13 and the rotating disk 11, and the history characteristics are almost constant.

Here, the load F generated in the MR resistance portion 1 of the wind lock mechanism A of the present embodiment is the shear resistance force Q of the MR fluid, the distance r from the center of rotation r, the resistance torque T of the ball nut portion, and the lead of the ball screw shaft. _Assuming that L d and the speed increasing ratio n of the speed increasing gear are set, they are expressed by the following equations (1) and (2).

The MR resistance portion 1 of the wind lock mechanism A of the present embodiment does not function as a mere damper, but adjusts a load (lock load) according to the wind speed so that the lock function for the wind of the seismic isolated building works properly. There is a need.

When it is desired to increase the lock load in the present embodiment, the distance r between the action position of the resistance resultant force of the MR fluid and the center of rotation (center of the ball screw shaft 7) is made larger than that of the conventional MR damper. As a result, the diameter of the rotating disk 11 can be increased, and the resistance torque T can be increased.

Further, when the resistance torque T is converted into the axial force, the lead (thread spacing) L _d of the ball screw shaft 7 is reduced _{because it is inversely proportional to the lead L d.}

Further, as shown in FIG. 5, the speed increasing mechanism 15 may be connected to the ball screw mechanism 9 that rotates the MR fluid. For example, if the MR fluid is rotated five times as large as the ball nut 8 by using a speed increasing mechanism 15 such as a planetary gear, the resistance torque T can be increased five times. A planetary gear can be used as the speed increasing mechanism 15, and the outer peripheral ring gear 16 is fixed to the casing 6, and three pinion gears 17 are arranged so as to be inscribed in the ring gear 16 and circumscribed in the central sun gear 18. For example, increase the speed increase ratio by 5 times.

Further, the material of the MR fluid composite 14 is selected, the number of turns of the coil 12a and the current are increased, and the magnetic field (magnetic flux density) acting on the MR fluid is increased.

When such a configuration is adopted, in the MR damper device 5 (MR resistance portion 1 of the wind lock mechanism A) of the present embodiment, when a displacement x occurs in the axial direction O1, the ball nut 8 rotates and the inner cylindrical body is formed. 10 is driven and rotated.

Since the sun gear 18 of the speed-increasing mechanism 15 is integrally connected to the inner cylinder 10 and the outer cylinder 12 and thus the fixed disk 13 are integrally connected to the casing 6, when the inner cylinder 10 rotates θ, the speed-increasing mechanism The sun gear 18 is rotated by 5θ by 15, and the relative rotation amount between the inner cylinder 10 of the MR resistance portion 1 and the outer cylinder 12 and the fixed disk 13 is also 5θ.

Here, the wind lock damper to be commercialized will be described from the result of manufacturing a small test piece of Non-Patent Document 1 and examining the reaction force of the MR damper device 5.

In the small test piece, a reaction force (shear resistance force) of about 20 kN can be obtained with a current of 0.5 A energizing the coil 12a.

Based on this, if the magnetic field (magnetic flux density) is the same and the diameter of the MR resistance unit 1 is doubled, the shear resistance resultant force Q is quadrupled and the distance from the center of rotation is doubled, so the resistance torque is 8. Double.

Since the rated load of the ball screw shaft 7 was 20 kN, the test piece was tested only with a reaction force of 30 kN or less, but if the damper strength is increased, the magnetic field can be increased to increase the reaction force, so the magnetic field is doubled here. Calculate as. However, since the ball screw mechanism 9 is also increased in size, the lead 30 at the time of the experiment is set to 50.

By using the speed-increasing mechanism 15 having a speed-increasing ratio of 5 times, the torque acting on the ball screw mechanism 9 becomes 5 times the torque generated in the MR resistance unit 1.

Therefore, when the product is commercialized with a size twice that of the small test piece, the torque generated by the MR resistance portion 1 is eight times that of the test piece. Also, doubling the magnetic field doubles it. Further, by changing the lead from 30 to 50, 3/5 = 0.6 times. Further, by using the speed increasing mechanism 15, it becomes 5 times. Therefore, it can be seen that the total can be increased by (8 × 2 × 0.6 × 5) 48 times. Incidentally, MR fluid area ² 2 = 4 times, 2 times the current and voltage to double the magnetic field, the power consumption becomes a factor 4 × 2 × 2 = 16.

Since the reaction force of the test piece is 20 kN, the damper reaction force when commercialized is about 960 kN (about 100 tonf). Since this is about the same as a general seismic isolation oil damper, it can be said that sufficient performance can be obtained in practical use.

On the other hand, in the wind lock mechanism A of the present embodiment, as shown in FIG. 1 (and FIGS. 2 to 5), power is generated by a wind power generation unit 2 (a wind power generator equipped with a wind turbine 2a or the like) installed in the upper part of the building. The generated power is supplied to the coil 12a of the MR resistance unit 1.

As a result, in the MR damper device 5 of the present embodiment, when the displacements at both ends occur, the ball screw shaft 7 rotates, and the inner cylindrical body 10 integrated with the ball screw shaft 7 rotates. Then, when the wind power generation unit 2 is driven by a strong wind or the like and power is supplied from the wind power generation unit 2 to the MR resistance unit 1, a magnetic field is formed, the viscous resistance of the MR fluid increases and becomes a resistance torque, and the ball screw mechanism 9 A large axial resistance force (reaction force) acts on the wind power.

In addition to supplying the generated power directly to the MR resistance unit 1, the following functions may be added via the control circuit.

A current (voltage) protection circuit is provided, and when the amount of power generation is large due to strong wind, the power supplied to the MR resistance unit 1 is leveled off. In this way, since the power of a predetermined value or more is not supplied, the reaction force of the MR resistance unit 1 also reaches a plateau.

Further, even when the wind is small, the seismic isolation layer 3 may be displaced due to the vibration of the superstructure T1 of the building. On the other hand, if a part of the power generation amount is stored and the power is continuously supplied to the MR resistance unit 1 for about 10 minutes even if the wind stops, the superstructure T1 can be generated with a small wind (wind load). It is possible to prevent the seismic isolation layer 3 from being displaced due to the vibration of.

Since the power supplied by the small test piece is 15 W / unit from a current of 0.5 A and a voltage of 30 V, the rated power of the commercialized damper is 16 times, which is 15 W / unit x 16 times = 240 W / unit. If a wind power generator with a rated output of 2 kW is installed, 2000 W ÷ 240 W / unit = 8.3 units, which means that power for eight MR dampers can be supplied. As a result, since the wind lock load in the seismic isolation layer 3 is 8 units × 960 kN = 7680 kN, it can be said that the plane is 30 m × 30 m and can be sufficiently applied to a 20-story building.

Therefore, in the wind lock mechanism A of the present embodiment, the wind lock mechanism A for preventing the wind sway of the seismic isolated building can be configured as a passive system without supply of an external power source. Therefore, it is possible to realize a highly reliable mechanism that does not cause any problem even in the event of a power failure.

Further, when the wind does not blow, power is not supplied from the wind power generation unit 2 to the MR resistance unit 1, and the reaction force of the MR resistance unit 1, that is, the lock load becomes almost 0, so that residual displacement due to the lock mechanism does not occur. Also, unlike the shear pin, it does not break, so there is no need to go to install it after an earthquake, and it is basically maintenance-free.

Further, the wind lock load can be arbitrarily set by controlling the coil current of the MR resistance unit 1. This makes it possible to easily set the upper limit of the lock load (locking load) by supplying electric power from the wind power generation unit 2 to the MR resistance unit 1 via the current control circuit.

Further, since the MR resistance portion 1 has a history characteristic similar to that of the friction damper and has high initial rigidity at the time of displacement restraint, the shaking of the seismic isolation layer 3 at the time of wind load can be made extremely small.

Further, the wind power generation unit 2 generates a large amount of power as the wind speed increases. Since this electric power is supplied to the MR resistance unit 1, the lock load increases as the wind load acting on the building increases. This makes it possible to build a rational system.

In addition, when an earthquake occurs during wind locking, it functions as a friction damper that regards the wind locking load as frictional resistance. In the normal design, it is not assumed that the wind and the earthquake act at the same time, but it can be treated as if a friction damper having a wind lock load is added by the wind lock mechanism A according to the present invention.
Since the wind load for design is generally much smaller than the seismic load, there is no problem in seismic resistance even if a wind lock is added. In addition, since the wind lock load is added, the response acceleration of the superstructure increases and the seismic isolation performance deteriorates a little. ..

Furthermore, it has a simple structure with little deterioration over time, and can be supplied at low cost if it is mass-produced.

Further, the joints at both ends of the MR resistance portion 1 can adopt the same configuration as the conventional oil damper, and no special skill is required for the installation work. Electrical work can be done easily because only the wiring is connected to the coil 12a.

Further, if the conventional viscous damper device and the MR damper section (MR resistance section 1) are integrally integrated to form a device, the viscous damping (C) and the MR resistance (R) are arranged in parallel, and the device is compact and inexpensive to manufacture. can.

Therefore, by providing the wind lock mechanism A of the present embodiment in the seismic isolation layer between the superstructure T1 and the substructure T2, the superstructure T1 can be automatically restrained or released without using external power. By controlling the movement of the superstructure T1 and the lower structure T2 when there is a strong wind and canceling the movement control state when there is no wind, it is possible to exert the seismic isolation effect on the superstructure T1 more reliably and effectively than before. become.

Although the embodiment of the wind locking mechanism according to the present invention has been described above, the present invention is not limited to the above embodiment and can be appropriately modified without departing from the spirit of the present invention.

1 MR resistance part 2 Wind power generation part 3 Seismic isolation layer 4 Seismic isolation device 5 MR damper device 6 Casing 7 Ball screw shaft 8 Ball nut 9 Ball screw mechanism 10 Inner cylindrical body 11 Rotating disk 12 Outer cylindrical body 12a Coil 13 Fixed disk 14 MR Fluid Composite 15 Speed Acceleration Mechanism 16 Ring Gear 17 Pinion Gear 18 Sun Gear A Wind Lock Mechanism O1 Axial Direction (Axis Line)
T1 superstructure T2 substructure

Claims (2)

The seismic isolation layer between the superstructure and the substructure is provided in parallel with the seismic isolation device, one end is connected to the superstructure and the other end is connected to the substructure to be horizontally arranged, and the superstructure and the substructure are arranged horizontally. When a relative displacement occurs in the MR damper device, an axial force is input, and
A wind power generation unit that generates electric power according to the magnitude of the wind acting on the superstructure and supplies electric power according to the magnitude of the wind to the coil of the MR resistance portion provided in the MR damper device .
Equipped with
The MR resistance unit is configured such that the magnetic field changes in magnitude according to the magnitude of the DC current value energized in the coil, and the resistance force changes in magnitude.
The MR damper device is
With the MR resistance sensor
The reaction force connected to the MR resistance section, converting the axial displacement due to the axial force into rotation and transmitting it to the MR resistance section, and converting the resistance torque of the MR resistance section with respect to the rotation into axial force is generated. The ball screw mechanism that works,
A wind lock mechanism characterized by being equipped with. The resistance of the MR resistance section is
It increases due to elastic deformation until a predetermined shear deformation occurs in the MR resistance portion, and after exceeding the predetermined shear deformation, it becomes a constant historical characteristic.
When the wind does not blow, it becomes almost 0.
The wind locking mechanism according to claim 1.

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