JPH0575540U - Seismic isolation device - Google Patents

Abstract

(57) [Abstract] [Purpose] The natural vibration period can be finely set without increasing the size of the device, and noise is generated even when horizontal force is applied and horizontal relative displacement occurs. And prevent the occurrence of impact. [Structure] A coil spring is composed of an outer peripheral side coil spring 1B and an inner peripheral side coil spring 1A which is provided inward of the outer peripheral side coil spring in parallel with and coaxially with the inner peripheral side coil spring 1A for fine adjustment of spring characteristics, and a conventional metal contact occurs. An annular bush 35 and a sliding member 37 made of resin having a small sliding resistance are provided at the portion that may be in danger.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 In order to protect expensive equipment such as precision equipment from unsteady external forces such as earthquakes, the present invention is a structure of a seismic isolation equipment installed between a seismically isolated support object such as precision equipment and a building floor. Regarding

[0002]

[Prior Art]

 Conventionally, in order to protect expensive equipment such as precision equipment installed in a building from the effects of unsteady external forces such as seismic external forces, seismic isolation devices have been installed on the floor and these devices have been used. Is elastically supported. Figure 6 shows a vertical section of a conventional seismic isolation device. This seismic isolation device uses the coil spring 1 to suppress vertical swaying. That is, the base plate 5 is installed on the building floor 3. A single coil spring 1 is provided around a center shaft 7 erected on the base plate 5, and a ring-shaped pressing plate 9 is arranged from above. The lower end of a bolt 13 screwed to a top plate 11 on which the seismic isolated support object is installed is in contact with the holding plate 9. As a result, the weight of the seismically isolated support object is elastically supported by the coil spring 1 via the top plate 11, the bolt 13, and the pressing plate 9. By designing the natural vibration cycle of the coil spring 1 to be different from the natural vibration cycle of the seismic isolated support object, it becomes possible to secure the vertical seismic isolation function. When the seismic isolation device is not operated, a stopper 14 is interposed between the top plate 11 side and the center shaft 7 to connect them to the load from above. As a result, the weight of the seismically isolated support object is supported not by the coil spring 1 but by the center shaft 7. The outer circumference of the coil spring 1 is surrounded by a spring casing 15 fixed to the base plate 5. Further, a casing 17 fixed to the top plate 11 is arranged on the outer periphery of the spring casing 15. Then, the bolt 18 screwed into the casing 17 comes into contact with the spring casing 15 to restrict the relative displacement in the horizontal direction.

As shown in FIG. 7, a constant gap is provided between the center shaft 7 and the through holes 19 and 21 at the center of the top plate 11 and the pressing plate 9. A horizontal relative displacement occurs only by this gap.

Further, as shown in FIG. 8, a gap also exists between the tip of the bolt 18 and the side surface of the spring casing 15, and the relative displacement in the horizontal direction is regulated by adjusting this gap.

[0005]

[Problems to be solved by the device]

 By the way, in the conventional seismic isolation device, it is difficult to set the period because the coil panel for adjusting the natural vibration period is a single arrangement, especially when the seismic isolation effect is obtained for precision equipment. If the cycle is too short or too long, it is not preferable, and it is particularly difficult to set a delicate cycle on the long cycle side. It may be possible to use an isolator or the like for fine adjustment to set such a period, but this makes the device larger and makes it difficult to universally use it in equipment with specific dimensions. was there.

In addition, when a horizontal force is applied to the top plate 11 when an external force such as an earthquake is applied, metal is applied between the center shaft 7 and the top plate 11 and between the bolt 18 and the spring casing 15. There was a risk of contact and noise and shock.

The present invention was devised in view of the above-mentioned conventional problems, and its purpose is to enable delicate setting of the natural vibration period without increasing the size of the device, and to set the natural vibration period in the horizontal direction. An object of the present invention is to provide a seismic isolation device capable of preventing noise and impact even when a force acts and a relative displacement occurs in the horizontal direction.

[0008]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, a first invention is a penetrating plate installed on a building floor and a penetrating plate which is installed above the base plate at a distance from each other and is attached to a seismic isolated support object side. A ring-shaped top plate having a hole, a center shaft erected on the base plate and movable with respect to the through hole of the top plate, and the center shaft between the base plate and the top plate. A first coil spring provided so as to surround the first coil spring, and a second coil spring provided inside the first coil spring in parallel with and coaxial with the first coil spring for finely adjusting spring characteristics. To do.

A second invention is that the center shaft is erected on a base plate installed on the building floor, and is elastically supported on a coil spring that surrounds the center shaft and is installed vertically. A ring-shaped top plate, through which the center shaft penetrates through a through hole formed in this, and a seismically isolated support object is installed above it, and the inner peripheral surface of the through hole of the top plate And a sliding member which is disposed between the facing outer peripheral surface of the center shaft and allows both of them to slide.

According to a third aspect of the invention, a center shaft erected on a base plate installed on the building floor, and a coil spring vertically provided around the center shaft and elastically supported, and A ring-shaped top plate on which the seismic isolated support object is installed, a cylindrical body casing provided on the base plate so as to surround the outer circumference of the coil spring, and the spring below the top plate. A cylindrical casing that surrounds the peripheral side surface of the casing, and is screwed into the peripheral side surface of the casing so as to abut against the peripheral side surface of the spring casing, and the relative horizontal displacement between them is regulated. And a sliding member that is arranged between the regulating member and the peripheral side surface of the spring casing with which the regulating member abuts, and that makes them slidable. It

[0011]

[Action]

 The operation of the present invention will be described. Since the second coil spring for finely adjusting the spring characteristics is provided inside the first coil spring in parallel with and coaxially with the first coil spring, there is no need to increase the size of the seismic isolation device. , The natural vibration period of the coil spring can be finely adjusted and set to a long period, and the period setting that is preferable for obtaining the seismic isolation effect can be secured with a compact structure, especially for precision equipment. .. Even when a horizontal force is applied to cause relative displacement in the horizontal direction, there is no contact between the top plate and the center shaft or between the regulating member and the spring casing via the sliding material. Since it is performed, it is possible to prevent the conventional metal contact.

[0012]

【Example】

 Hereinafter, a preferred embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a vertical sectional view of the seismic isolation device according to the present embodiment. The same parts as those in the conventional example are designated by the same reference numerals.

The present invention is basically provided with a base plate 5 installed on a building floor 3 and a space above the base plate 5 and is attached to a seismically isolated supporting object side such as precision equipment. A ring-shaped top plate 11 having a through hole 25, a center shaft 7 standing on the base plate 5 and movable with respect to the through hole 25 of the top plate 11, the base plate 5 and the top plate 11. A first coil spring 1B provided around the center shaft 7 between the first coil spring 1B and a second coil spring 1A provided inside the first coil spring 1B coaxially therewith for fine adjustment of spring characteristics. It is composed of

Further, according to the present invention, the center shaft 7 installed upright on the base plate 5 installed on the building floor 3 and the coil springs 1A and 1B provided around the center shaft 7 in the up-down direction are elastic. A ring-shaped top plate 11 on which the center shaft 7 is supported and through which the center shaft 7 penetrates, and the seismically isolated support object is installed above the center shaft 7, and the through hole 25 of the top plate 11. An annular bush 35 as a sliding member is disposed between the inner peripheral surface and the outer peripheral surface of the center shaft 7 opposed to the inner peripheral surface, and makes them slidable.

Further, according to the present invention, the center shaft 7 standing on the base plate 5 installed on the building floor 3 and the coil springs 1A and 1B provided around the center shaft 7 in the vertical direction are elastic. A ring-shaped top plate 11 which is supported and on which a seismically isolated support object is installed, and a cylindrical spring casing 15 which is provided on the base plate 5 so as to surround the coil springs 1A and 1B. A cylindrical casing 17 is provided below the top plate 11 so as to surround the peripheral side surface of the spring casing 15, and the peripheral side surface of the casing 17 is screwed into the peripheral side surface of the spring casing 15 so as to come into contact therewith. These bolts 18 are arranged between the bolt 18 as a regulating member for regulating the relative displacement in the horizontal direction between the two and the peripheral surface of the spring casing 15 with which the bolt 18 abuts. And a sliding member 37 that allows the person to slide.

Specifically, the base plate 5 is installed on the building floor 3. A center shaft 7 is supported by a support bracket 23 at approximately the center of the base plate 5, and is fixed by welding or the like. Around the center shaft 7, an inner peripheral side coil spring 1A and an outer peripheral side coil spring 1B are doubly provided. The upper surfaces of these two coil springs 1A and 1B are pressed by an annular pressing plate 9. A ring-shaped top plate 11 is provided parallel to the pressing plate 9 in a rigid state in which a load from above can be transmitted. That is, the bolt 13 is screwed into the top plate 11, and the lower end of the bolt 13 is in contact with the upper surface of the pressing plate 9. The bolt 13 enables the elasticity of the two coil springs 1A and 1B to be adjusted.

The center shaft 7 penetrates the holding plate 9 and the top plate 11. In the vicinity of the through hole 25 of the top plate 11, a locking bracket 27 surrounding the through hole 25 is fixed by welding or the like. The locking bracket 27 has a substantially U-shaped vertical cross section, and a through hole 29 is formed in the center thereof. The tip of the center shaft 7 having a smaller outer diameter can pass through the through hole 29. However, in a normal state, a stopper plate 31 which is larger than the through hole 29 of the locking bracket 27 is inserted between the locking bracket 27 and the top of the center shaft 7 and elastically supported by the coil springs 1A and 1B in the normal state. In order to prevent the seismically isolated supporting object from becoming unstable. That is, when the stopper plate 31 is inserted, the weight of the seismically isolated support object is transmitted to the building floor 3 via the top plate 11, the locking bracket 27, the stopper plate 31, the center shaft 7, and the base plate 5. ..

On the other hand, when an earthquake or the like occurs and the seismic isolation function is exerted, the stopper plate 31 is removed and the load is not transmitted between the center shaft 7 and the locking bracket 27. .. As a result, the seismically isolated support object is elastically supported on the building floor 3 via the top plate 11, the bolt 13, the pressing plate 9, the coil springs 1A and 1B, and the base plate 5.

The seismic isolated support object is installed on the top plate 11 using the installation fitting 33.

As shown in FIG. 2, on the inner peripheral surface of the through hole 25 of the top plate 11, there is provided an annular bush 35 made of a sliding material made of resin (for example, Teflon: trade name) having a small sliding resistance. It is provided.

As shown in FIG. 3, the tip of the bolt 18 of the casing 17 fixed to the top plate 11 can come into contact with the cylindrical spring casing 15 surrounding the outer circumferences of the coil springs 1A and 1B. There is. At the tip of the bolt 18, a sliding member 37 made of resin having a small sliding resistance is embedded in the same manner as described above.

A hydraulic damper 38 is provided between the casing 11 and the base plate 5 to prevent the coil springs 1A and 1b contracted by vibration from returning suddenly, and to further improve the seismic isolation function. I am raising.

According to the above-described embodiment, the coil spring is provided in the inner coil spring 1A and the outer coil coil 1B in a double manner, so that the natural vibration period of the coil spring can be increased without enlarging the overall shape of the seismic isolation device. Can be adjusted to set longer. For example, when one coil spring was provided, the cycle was about 0.4 to 0.5 seconds, but it is possible to make it about 0.6 to 0.7 seconds by providing two coil springs. Becomes Therefore, it is possible to secure a preferable period setting with a compact structure, particularly when a seismic isolation effect is obtained especially for precision equipment.

Further, even when a horizontal force acts on the seismic isolation device and a relative displacement occurs in the horizontal direction, the through hole 25 of the top plate 11 has the annular bush 35 made of the sliding material. It contacts with the center shaft 7 via (FIG. 2). Further, the tip of the bolt 18 for restricting the relative displacement in the horizontal direction also contacts the side surface of the spring casing 15 via the sliding member 37 (FIG. 3). Therefore, a metal contact unlike the conventional case does not occur, and a large noise and impact generated by the metal contact can be prevented.

On the other hand, in the above embodiment, as the annular bush 35, the one that makes line contact with the center shaft 7 is illustrated, but as shown in FIGS. 4 and 5, point contact with the center shaft 7 is made. A ring-shaped bush 39 having a spherical surface may be used, and as for the arrangement, as long as it is between the inner peripheral surface of the through hole 25 and the outer peripheral surface of the center shaft 7, the top plate 11 side, the center shaft. It may be arranged on any of the seven sides. Further, in the above embodiments, the contact surface of the sliding member 37 at the tip of the bolt 18 with the spring casing 15 is a flat surface (FIG. 3), but in other embodiments it can be a spherical surface. Further, the sliding member 37 may be provided not on the tip of the bolt 18 but on the outer peripheral surface of the center shaft 7 in contact with the bolt 18.

[0026]

[Effect of the device]

 As described above, according to the seismic isolation device of the present invention, the second coil spring for finely adjusting the spring characteristics is provided inside the first coil spring coaxially and in parallel with the first coil spring. The natural vibration period of the coil spring can be fine-tuned and set long without increasing the overall shape of the device, and the period setting preferable for obtaining the seismic isolation effect is targeted especially for precision equipment. It can be secured in the configuration. Even when a horizontal force is applied to cause relative displacement in the horizontal direction, contact is made between the top plate and the center shaft, or between the regulating member and the spring casing via a sliding material. Therefore, the conventional metal contact does not occur, and it is possible to prevent a large noise and impact generated by the metal contact.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a seismic isolation device according to an embodiment of the present invention.

FIG. 2 is an enlarged view of part A in FIG.

FIG. 3 is an enlarged view of part B in FIG.

FIG. 4 shows another embodiment of the present invention and is a view corresponding to FIG.

FIG. 5 shows still another embodiment and is a diagram corresponding to FIG.

FIG. 6 is a vertical sectional view of a conventional seismic isolation device.

FIG. 7 is an enlarged view of portion C of FIG.

FIG. 8 is an enlarged view of part D in FIG.

[Explanation of symbols]

 1A Inner circumference side coil spring 1B Outer circumference side coil spring 3 Building floor 5 Base plate 7 Center shaft 9 Holding plate 11 Top plate 13 Bolt 15 Spring casing 17 Casing 18 Bolt 35 Annular bush 37 Sliding material

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yukio Okuda 2-3 Kandajimachi, Chiyoda-ku, Tokyo Obayashi Corporation Tokyo Head Office (72) Kazuhisa Kaneda 2-3 Kandajimachi, Chiyoda-ku, Tokyo Stock company Obayashi Corporation Tokyo head office (72) Inventor, Yuzuru Yasui 4-640 Shimo-Seido, Kiyose-shi, Tokyo Inside Obayashi Technical Research Institute, Inc. (72) Masataka Kaneko 4-640, Shimo-Seido, Kiyose-shi, Tokyo Obayashi Technical Research Co., Ltd. In-house

Claims (3)

[Scope of utility model registration request] 1. A base plate installed on a building floor, a ring-shaped top plate having a through hole, which is provided above the base plate with a space therebetween and is attached to the seismic isolated support object side. A center shaft that is erected on the top plate and is movable with respect to the through hole of the top plate; a first coil spring that is provided between the base plate and the top plate to surround the center shaft; A second coil spring that is provided inside the coil spring in parallel with and coaxially with the coil spring and that finely adjusts spring characteristics. 2. A center shaft erected on a base plate installed on a building floor, and a coil spring that surrounds the center shaft and is elastically supported on a coil spring provided in the up-and-down direction. A ring-shaped top plate, through which the center shaft penetrates the hole, and a seismic isolated support object is installed above the center shaft, an inner peripheral surface of the through hole of the top plate, and a center shaft facing the inner peripheral surface of the through hole. A seismic isolation device, comprising: a sliding member that is disposed between the outer peripheral surface and both of them and is slidable. 3. A center shaft erected on a base plate installed on the floor of the building, and a coil spring vertically provided around the center shaft and elastically supported on the center shaft, and seismically isolated support above the coil spring. A ring-shaped top plate on which an object is installed, a cylindrical spring casing provided on the base plate so as to surround the outer periphery of the coil spring, and a peripheral side surface of the spring casing below the top plate. A cylindrical casing provided, a regulating member that is screwed into the peripheral side surface of the casing so as to come into contact with the peripheral side surface of the spring casing, and that regulates horizontal relative displacement between the both, and the regulating member. And a sliding member which is disposed between the spring casing and the peripheral side surface of the spring casing with which the spring abuts, and which makes them slidable, a seismic isolation device.