JP2512956Y2 - Structural vibration control device - Google Patents

Description

[Detailed Description of the Invention] [Industrial application] The present invention is installed on the upper part of a structure such as a tower of a suspension bridge, a skyscraper, a tower, a steel tower, etc. The present invention relates to a structure damping device used to suppress the vibration amplitude due to an earthquake and to damp the vibration early.

[Prior Art] Conventionally, as this type of structure vibration damping device, for example, as disclosed in Japanese Patent Laid-Open No. 60-92569, a detection means for detecting the vibration amount of a vibrating object and this detection means. A vibration control device having a drive device for applying a control force corresponding to the amount of vibration detected by the vibrating object to the vibrating object, and an additional weight for achieving a balance of forces when the control force is applied to the vibrating object. Of the structure which is provided with a stopper for restricting excessive movement of the above and a cushioning member for absorbing the impact force of the additional mass on the stopper, as shown in Japanese Patent Laid-Open No. Sho 60-92570. A weighted weight drive device is installed, the vibration of the structure is detected by a vibration detector, and a control signal is generated by a control circuit based on this detection signal, and the drive of the additional weight drive device is controlled by this signal. , Shaking the above structure In this system, a structure vibration prediction sensor consisting of a ground motion detector and a logic circuit installed on the ground is provided, and the output can supply power to the additional weight drive device to control vibration. Those made to be in a state, as shown in JP-A-59-97341,
An additional weight movably mounted on the floor or ceiling of the structure, an actuator that drives the additional weight, with a stationary portion fixed to the floor or ceiling, and a controller that operates the actuator, Vibration detector attached to the structure to detect the vibration of the structure, vibration detector attached to the ground of the structure to detect the vibration of the ground, and vibration of the ground from the detection signal of the vibration detector of the structure A subtraction circuit for subtracting the detection signal of the detector and inputting it to the control unit, and as shown in JP-A-60-85165, an additional weight driving device is attached to the structure. A band filter is installed between the vibration detector and the additional weight driving device in a structure in which the actuator of the additional weight driving device is installed based on a signal from the vibration detector that detects the vibration of the structure. Was connected Of, and the like.

[Problems to be Solved by the Invention] However, the structure disclosed in JP-A-60-92569 has a complicated structure because it has a stopper and the like. The disclosed device has a complicated control device due to a ground motion detector on the ground.
The one disclosed in JP-A-59-97341 needs a plurality of vibration detectors because it requires a subtractor, and the one disclosed in JP-A-60-85165 requires a band-pass filter. There are problems such as the need for extra circuits. Further, in each of the above-mentioned conventional systems, since the driving body is simply moved in a straight line, the entire apparatus is large and lacks a concrete means for controlling the driving body. Furthermore, the phase relationship regarding the vibration of the structure and the specific movement of the driving body of the vibration damping device is not clear.

Therefore, the present invention solves the above-mentioned problems, effectively damps the structure by giving the vibration of the vibration suppressor to the structure in an optimum phase, and suppresses the vibration of the vibration suppressor. It is intended to realize a compact design by performing an ideal trajectory along a parabola, and to save labor by vibrating the damping body by semi-active control.

[Means for Solving the Problems] In order to solve the above problems, the present invention has a structure in which a bracket is erected on the upper part of a structure with a required space in the front and rear, and lower guide rollers are provided on the brackets on the front and rear sides. Each of them is installed, and on the lower surface, a damping body having a curved surface along the path of a parabola formed in an arch shape is supported on the lower guide rollers on both the front and rear sides so that the curved surface of the lower surface can be vibrated in the left and right directions. On both front and rear surfaces of the vibration damping body, guide rails having an arch shape parallel to the curved surface of the lower surface are provided, and an upper guide roller rolling on the upper surface of the guide rail is placed on the structure to put the vibration damping body from both front and rear sides. It is attached to a fixed support frame so as to sandwich it, so that the vibration damper is guided by the upper and lower guide rollers to move in the left-right direction along the parabola, and along the curved surface at the center of the lower surface of the vibration damper. hand A rack is attached, a pinion that meshes with the rack is installed on a structure so that the structure is driven by a drive device installed on the structure, and the structure is swayed above the structure. A sway detection sensor for detecting is provided, and a phase control device for sending a control command for controlling the phase of the signal of the sway detection sensor to semi-actively control the vibration damper to the drive device is provided. .

[Operation] When the sway of the structure is detected by the sway detection sensor, the signal is phase-controlled by the phase control device and then output to the vibration damping body drive device. Since the damping body needs to be given only the braking force after being accelerated to the required amplitude, the vibration of the damping body is controlled semi-actively. Since the energy given as a single string vibration to this vibration control body is given to the structure in an optimum state, the vibration of the structure can be quickly suppressed. At this time, in the vibration damper, the arched curved surface of the lower surface is supported by the fixed lower guide roller, and the arched guide rails provided on the upper and lower front and rear surfaces are supported by the fixed upper guide roller. Since it vibrates along the parabola trajectory, ideal movement can be stably obtained and the power applied to the vibration damper can be reduced.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings. .

FIG. 1 shows an embodiment of the present invention applied to a tower of a suspension bridge as a structure that vibrates when receiving an external force. A vibration damping device main body 2 and a shake detection sensor 3 are attached to the top of the tower 1 of the suspension bridge. . That is, the vibration damping device main body 2 attached to the top of the tower 1 has a base 4 extending in the swinging direction of the tower 1 (left and right direction in FIG. 1) as shown in FIGS. 2 and 3 in detail. Installed on the base 4, above the base 4, a semicircular curved surface 5a on the lower surface along the locus of a parabola
And the curved surface 5a is formed at two places on the left and right, and a weight 5 as a vibration damping body is arranged. Each curved surface 5a of the weight 5 is mounted on the base 4 via a bracket 6. The weights 5 are supported at two points in the left-right direction by being supported by the front and rear lower guide rollers 7 installed respectively, and the center portions of the curved surfaces 5a of the weight 5 in the front-rear direction are aligned with the curved surface 5a. A rack 8 is fixed to each of the racks 8, and a pinion 10 installed on the base 4 via a bracket 9 is meshed with each rack 8 and a transmission gear is transmitted to each pinion 10.
11 are meshed with each other, and motors 12 are installed at the front and rear ends of the base 4, and the bevel gears 14a are respectively attached to the output shafts of the speed reducers 13 connected to the motors 12.
And the bevel gears 14a to the transmission gear 1
Mesh with the bevel gears 14b attached to the shaft of 1,
By synchronously driving both motors 12, the pinion 10 is rotated via the bevel gears 14a, 14b and the transmission gear 11, respectively, and the weight 5 is guided by the lower guide rollers 7 to the left and right with the rack 8 along the parabola. It can be moved (vibrated) in the desired direction at a required cycle. Furthermore,
On the base 4, a gate-shaped support frame 15 is erected so as to face the weight 5 from the front and back, and the weight 5
Guide rails 16 each having an arch shape are provided in parallel with the curved surface 5a on the front and rear surfaces of the
The upper guide rollers 17 are attached to the upper portions of the inner side surfaces of the respective support frames 15 so as to engage with the upper surface of It is possible to guide, and a protrusion is further provided at the center of at least one surface of the weight 5 in the longitudinal direction.
18 is provided so that the moving region of the weight 5 is restricted within the range in which the protrusion 18 contacts the left and right buffers 19 provided on the inner surface of the support frame 15. In addition, 20 is a bevel gear 14 in order to adjust the cycle of vibration of the weight 5 by rotational inertia.
It is a weight for adjusting the vibration period that is attached coaxially with b.

Further, the shake sensor 3 is attached to the upper part of the tower 1 so as to detect the shake of the tower 1. Further, in the present invention, a phase controller for controlling the phase of the signal from the sensor 3 is provided, The motor 12 is driven based on the phase signal output from the phase control device, and the driving force of the motor 12 arbitrarily controls the phase of the single string vibration of the weight 5 with respect to the shaking of the tower 1. The shaking of No. 1 is suppressed within the allowable shaking range and the kinetic energy of the tower 1 is consumed.

The driving force of the motor 12 is a power for accelerating the weight 5, and is also a braking force that gives a damping force for holding the amplitude required by the weight 5. That is, since the energy given to the weight 5 as a single-string vibration due to the shaking of the tower 1 diverges unless a control force is applied, the weight of the weight 5 is accelerated to the required amplitude by driving the motor 12. A control force and a braking force that suppresses divergence are given.

Incidentally, when the weight 5 is considered as a pendulum as shown in FIG. 4, its natural vibration period T is the vibration radius R of the center of gravity G.
Is determined by That is, Further, when the weight of the weight 5 is m and the horizontal displacement amount is x, the vertical displacement amount y is Can be obtained as

Next, the principle of phase control in the present invention will be described with reference to FIG. In FIG. 5, 34 is a vibrating table vibrated by the actuator 35, 36 is a specimen (corresponding to the tower 1 in FIG. 1) movably mounted on the vibrating table 34, and 37 is a weight ( (Corresponding to the weight 5 in FIG. 2), 38 and 39 are brackets. Now, let P be the aerodynamic force (wind load) acting on the specimen 36, the mass of the specimen 36 be M, the reduced spring constant of the specimen 36 be K, and the damping coefficient of the specimen 36 (additional damping constant: 2 Mhω). C,
Let X be the amount of horizontal displacement (absolute coordinates) of the specimen 36, the mass of the weight 37 is m, the spring constant of the weight 37 is k, and the weight 37.
Where p is the control force for controlling the vibration of the weight and x is the linear displacement of the weight 37 in the horizontal direction (relative coordinates with respect to the specimen 36),
The equations of motion of the specimen 36 and the weight 37 are: M + CX + KX + m (+) = Pcosωt (1) (ω: natural frequency, t: time) m + m + kx = p (t) (2) Here, the specimen 36 and Assuming that the weight 37 is performing a single string motion, X = Asinωt (3) (A: amplitude) x = Bsin (ωt + α) (4) (B: amplitude, phase difference with respect to α: ωt) At this time, the spring constants K and k and the specimen 36 and the weight 37 have the following relationship: K = (M + m) ω ² (5) k = mω ² (6) Therefore, the terms including the mass and the spring constant in the equations (3) and (4) are always zero as follows.

(M + m) + KX =-(M + m) A [omega] ² sin [omega] t + (M + m) A [omega] ₂ sin [omega] t = 0 (7) m + kx = -mB [omega] ² sin ([omega] t + [alpha]) + mB [omega] ² sin ([omega] t + [alpha]) = 0 (8) (7), Substituting equation (8) into equations (1) and (2), Pcosωt = CX + m = 2MhAω ² cosωt−mBω ² sin (ωt + α) (9) p (t) = m = −mAω ² sinωt (10) ) Here, equation (9) shows that the force due to the damping of the specimen 36 and the motion of the weight 37 is in balance with the aerodynamic force P when the phases of the first and second terms on the right side are the same. ing. That is,
When the motion of the weight 37 operates 90 degrees behind the motion of the specimen 36 (-90 °), a force acts in the same direction as the damping of the specimen 36 to stop the vibration. I understand. Therefore, if α = −90 ° and equation (9) is rewritten, Pcosωt = 2MhAω ² cosωt + mBω ² cosωt = (2MhA + mB) ω ² cosωt (11) The amplitude B of the weight 37 is m · B = (P / ω ² ) −2MhA (12) according to the equation (11).

What is clear from these equations is that the damping device is active or passive, and therefore the force p shown in equation (10) is the control force or the passive type in the case of the active type. In this case, it can be considered as a damping force.

The above-mentioned formula for the principle can be translated into words as follows.

The force of the vibration damping device for suppressing the vibration of the structure (the tower 1 of this embodiment) is obtained by the movement of the mass of the vibration damping device.

A stable vibration is provided to the vibration damping device by applying the opposite force having the same magnitude as the force entering the structure as a control force or a damping force.

In other words, energy such as aerodynamic force that enters the structure is converted into kinetic energy of the vibration damping device, which is consumed by the damping mechanism of the vibration damping device. The principle of a vibration damping device is that it can suppress shaking.

From the above, the weight 5 of the tower 1 and the vibration damping device main body 2
It can be seen that the phase difference of the displacement of should be 90 °. The figure is shown in FIG. Here, if the displacement is differentiated once from FIG. 6 (a), the velocity can be obtained as shown in FIG. 6 (b). If the velocity is differentiated once again, the acceleration can be obtained as shown in FIG. Incidentally, in FIG. 6, the solid line shows the movement of the structure, and the broken line shows the movement of the weight. Therefore, in the present invention, the sway detection sensor 3 is used as an acceleration sensor, and the sway of the tower 1 is measured by the sway detection sensor 3 as acceleration, and this acceleration is integrated once to obtain the tower 1.
By comparing the speed signal with the displacement signal of the weight 5 and applying a signal obtained by inverting the speed signal of the tower 1 as the speed signal of the weight 5 to the drive unit of the vibration damping device main body 2. The displacement of the weight 5 is delayed by 90 ° with respect to the displacement of the tower 1.

A control block diagram for performing the phase control is shown in FIG.
As shown in the figure. That is, 21 is the shake detection sensor 3
The first integrator 22 which integrates the acceleration signal α ₁ detected in step 22 reverses the sign of the speed signal v ₁ which is the output of the first integrator 21, and through the contact 23a of the relay 23, the drive unit 24 for the motor 12 An amplifier for sending a drive command to the drive unit 25, a pulse generator for sending a feedback signal to the drive unit 24 for equalizing the rotation speed of the motor 12 with the signal from the amplifier 22, and 26 a signal V ₁ from the first integrator 21. A second integrator for further integrating once, 27 is a comparator for comparing the displacement signal l ₁ from the second integrator 26 with an arbitrary set value,
Reference numeral 23 is the relay described above, which is excited when the displacement signal l ₁ compared with the set signal by the comparator 27 is larger than the set value to turn on the contact 23a, rotate the motor 12 and move the weight 5 to the left or right. It can be moved to.
Reference numeral 28 is a displacement indicator for displaying the output signal of the second integrator 26. The comparator 27 is for moving the weight 5 when the tower 1 exceeds a certain swing range, but is not always necessary. Also, the displacement indicator 28
Is additionally provided and is not absolutely necessary.

The block diagram of FIG. 7 will be specifically described. When acceleration is detected by the shake detection sensor 3 which is the acceleration detection sensor attached to the tower 1, the signal α ₁ is integrated by the first integrator 21 to become the velocity signal V ₁ . Next, the sign of the speed signal V ₁ is inverted by the amplifier 22 and then input to the drive unit 24, so that the weight 5 is moved left and right by rotating the motor 12. On the other hand, the velocity signal V ₁ from the first integrator 21 becomes a displacement signal l ₁ by being integrated once more by the second integrator 26, and this displacement signal l ₁ is compared with the set value by the comparator 27, If it is larger than the set value, the signal from the comparator 27
23, the amplifier 22 and the drive unit
The contact 23a between 24 and 24 is turned on.

In the above description, the weight 5 is vibrated so as to perform single-string vibration along the locus along the parabola, and thus can be driven with a small power. Therefore, the motor 12 to be used may be of small size and small capacity, and the entire device can be designed compactly. Further, since the vibration energy of the weight 5 is also given by the shaking of the tower 1, after the weight 5 is accelerated to the required amplitude, the driving force of the motor 12 may be given as a braking force. The vibration damping effect can be obtained only by active activation. Therefore, the power used by the motor 12 can be small.

By the way, when the tower 1 sways in a quick cycle, the drive system of the vibration damping device main body 2 may be delayed. 8th
The figure shows a circuit for correcting the delay of the drive system. That is, 29 is an A / D converter for digitizing the signal output from the first integrator 21, and 30 is the A / D converter.
A memory that stores the signal data from 29 in synchronism with the clock signal input to its a terminal, 31 is a phase setter
A phase controller that sends the phase set in 32 to the memory 30 and controls the transmission / reception of data in the memory 30, 33 converts the data output from the memory 30 into an analog signal, and through the contact 23a of the relay 23 to the drive unit 24. It is a D / A converter sent as a drive command.

In the circuit of FIG. 8, the signal α ₃ detected by the shake detection sensor 3 is converted into the speed signal V ₃ by the first integrator 21, and then digitized by the A / D converter 29 and stored in the memory 30. . The memory 30 stores V ₃ data for an arbitrary period for the first time in synchronization in synchronization with the clock signal applied to the a terminal, and at the same time, outputs an arbitrary phase by a command from the phase controller 31 based on the value set by the phase setter 32. Eject data with a delay. In this case, since the memory 30 can discharge the data according to the phase set by the phase setting device 32, the phase can be freely set in response to a rapid change in speed, so that the delay of the servo system can be corrected. That is, when the memory 30 is not used, the movement of the weight 5 (two-dot chain line) is delayed due to the servo delay as shown in FIG. 9, but when the memory 30 is used, it is shown in FIG. When the delay time Δt (3/4 Hz in this embodiment) is folded in the servo system, the weight 5
The movement of can be corrected. In other words, the phase can be adjusted by an arbitrary cycle to control while correcting the delay of the servo system.

In addition, although the example of adopting the suspension bridge to the tower 1 is illustrated in the above-mentioned embodiment, it can be similarly applied to the high-rise building 1'and other structures as shown in FIG. 11, and in the embodiment, The case where the curved surface 5a along the parabola is formed at two places on the lower surface of the weight 5 is shown as an example, but this is good for one point support in order to move along the trajectory of the parabola, but it is necessary to support the weight in order to support it during vibration. The purpose of this is to stabilize the operation of No. 5 by supporting at two points, and it is also possible to arbitrarily use it as a vibrating device by controlling the phase so as to advance with respect to the vibration of the structure. It goes without saying that various changes can be made without departing from the above.

[Effects of the Invention] As described above, according to the structure damping device of the present invention,
Brackets are erected on the upper part of the structure at a predetermined distance in the front and back, lower guide rollers are installed on the front and rear brackets, respectively, and a curved surface along the trajectory of a parabola is formed in an arch shape on the lower surface. The body is supported so that it can be vibrated in the left-right direction by placing the curved surface of the lower surface on the lower guide rollers on both the front and rear sides, and on the front and rear side surfaces of the damping body
An arch-shaped guide rail that is parallel to the curved surface of the lower surface is provided, and an upper guide roller that rolls on the upper surface of the guide rail is attached to a support frame that is fixed on the structure so as to sandwich the vibration damper from both front and rear sides. The damping body is guided by upper and lower guide rollers to move in the left-right direction along a parabola, and a rack is attached to the center of the lower surface of the damping body along a curved surface and meshes with the rack. A pinion is installed on a structure so that it can be driven by a drive device installed on the structure, and a shake detection sensor for detecting the shake of the structure is provided on the upper part of the structure, and A phase control device for sending a control command for phase-controlling the signal of the shake detection sensor to semi-actively control the vibration suppressor to the drive device, and controlling the phase control device. Therefore, the energy of the vibration control body that oscillates along the trajectory along the parabola can be optimally given to the structure, so that the vibration of the structure can be quickly suppressed, and the control system is simple, so the price is low. It is cheap and easy to maintain, and further, the curved surface formed in the shape of an arch on the lower surface is supported by the fixed lower guide roller, and the guide rails provided in the upper and lower front and rear surfaces in parallel with the curved surface are provided on the upper guide roller. The vibration damping body is caused to vibrate along a locus along the parabola by engaging with the vibration damping member, so that the vibration damping body can be stably vibrated and the entire device can be designed compactly, and the vibration damping body Since the vibration damping effect can be obtained simply by operating the semi-actively, it is possible to achieve an excellent effect such as labor saving.

[Brief description of drawings]

FIG. 1 is a schematic view showing the structure damping device of the present invention applied to a tower of a suspension bridge, FIG. 2 is a front view showing the structure of the damping device main body, and FIG. 3 is a side view of FIG. , FIG. 4 is an explanatory view showing a vibration system of a pendulum, FIG. 5 is a view showing a model of the principle of the present invention, and FIG. 6 is a view showing a relation between a structure and a weight. Is the displacement, (b) is the velocity,
(C) is a diagram showing acceleration respectively, FIG. 7 is a block diagram showing one embodiment of the phase control device in the present invention, and FIG. 8 is a block showing one example of a circuit for correcting the delay of the servo system. Fig. 9 is a diagram showing the displacement when the servo system delay is not corrected, Fig. 10 is a diagram showing the displacement when the servo system delay is corrected, and Fig. 11 is the present invention applied to a high-rise building. It is the schematic of a case. 1 ... Suspension bridge tower, 2 ... Vibration control device main body, 3 ... Vibration detection sensor, 5 ... Weight (vibration control body), 5a ... Curved surface, 7 ...
… Lower guide rollers, 8 …… Rack, 10 …… Pinion,
12 …… motor, 15 …… support frame, 16 …… guide rail, 17 …… upper guide roller, 21 …… first integrator, 23…
… Relay, 24 …… Drive unit, 26 …… Second integrator, 27 …… Comparator, 30 …… Memory, 31 …… Phase controller.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-59-217028 (JP, A) JP-A-61-70243 (JP, A)

Claims (1)

(57) [Scope of utility model registration request] 1. A bracket is erected on the upper part of a structure at a predetermined distance in the front-rear direction, lower guide rollers are installed on the front and rear brackets, and a curved surface along the locus of a parabola is arched on the lower surface. The damping body formed on the lower guide rollers on both the front and rear sides is supported so that it can vibrate in the left and right direction, and the front and rear side surfaces of the damping body are parallel to the lower curved surface. A guide rail with a unique arch shape is provided, and an upper guide roller that rolls on the upper surface of the guide rail is attached to a support frame that is fixed on the structure so that the damper is sandwiched from the front and rear sides. Is guided by a guide roller to move in the left-right direction along a parabola, and a rack is attached to the central portion of the lower surface of the damping body along a curved surface, and a pinion that meshes with the rack is constructed. It is installed on the structure so that it can be driven by a driving device installed on the structure, and a shake detection sensor for detecting the shake of the structure is provided on the upper part of the structure, and further the shake detection is performed. A structural vibration damping device comprising a phase control device that sends a control command for phase-controlling a signal of a sensor to semi-actively control the vibration damping body to the drive device.