JP2008025748A - Seismic isolator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seismic isolator which maintains smooth rolling of a rolling element by lubrication, and prevents intrusion of foreign matter from the outside. <P>SOLUTION: The seismic isolator is provided with: one large diameter rolling element 4 interposed so as to freely roll between a base plate 2 and a support element 3; and a plurality of small diameter rolling elements 5. A spherical rolling face 6 supporting the plurality of small diameter rolling elements 5 such that they roll along a surface of an upper part of the large diameter rolling element 4 in an arranged state, and a circulation path 7 are provided in the support element 3. In the seismic isolator 1, a gap between the large diameter rolling element 4 and an opening rim of a large diameter rolling element holding recessed part 9b provided in the support element 3 to provide fitting of the large diameter rolling element 4 in a rollable state, is sealed by a solid lubricant 10. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a seismic isolation device that is installed between the ground and a structure such as a building, and suppresses the shaking of the structure when an earthquake occurs, and in particular, is provided with a rolling element interposed between a base plate and a support body. The present invention relates to a seismic rolling type seismic isolation device.

2. Description of the Related Art Conventionally, as a rolling support type seismic isolation device, there is one in which rolling elements made of two types of large and small steel balls are interposed between a base plate and an external member corresponding to a rolling support portion (for example, Patent Document 1). . This is because a plurality of small-diameter rolling elements arranged in the case circulate around one large-diameter rolling element, so that the movement of the support part on the base plate is smooth, and buildings such as during an earthquake It suppresses the shaking.
In such a seismic isolation device, a lubricant such as grease is applied to large and small rolling elements so that the rolling elements smoothly roll. In addition, a seal member is provided between the rolling element housing concave portion of the support body and the rolling element to prevent entry of foreign matter such as earth and sand and dust from the outside.
Japanese Patent Laid-Open No. 11-36659 JP 2003-213960 A Japanese Patent Publication No. 63-23239

  Such a rolling bearing type seismic isolation device is often laid under the floor of the structure in order to suppress the shaking of the structure at the time of the earthquake, and is likely to rust due to condensation, etc. because it is outdoors. . Moreover, when foreign matter such as earth and sand or dust enters, the foreign matter may be bitten, and the seismic isolation function may not work normally when an important earthquake occurs.

  As a rolling bearing type seismic isolation device, Patent Document 2 describes that a rolling element is subjected to a surface treatment for rust prevention in order to prevent rusting. However, this does not disclose a technique related to the seal member, and there is a concern that foreign matters such as earth and sand and dust enter the rolling support portion.

  An object of the present invention is to provide a seismic isolation device that can maintain a smooth rolling of a rolling element by lubrication and prevent entry of foreign matter from the outside.

  The seismic isolation device according to the present invention includes a base plate, a support body positioned above the base plate, one large-diameter rolling element and a plurality of small-diameter rolling elements that are interposed between the base plate and the support body in a freely rolling manner. A spherical rolling surface that supports the plurality of small-diameter rolling elements in an aligned state along the upper surface of the large-diameter rolling element, and a peripheral edge of the rolling surface. In the seismic isolation device provided with a circulation path for circulating the small-diameter rolling element on the rolling surface, the peripheral edge of the opening of the large-diameter rolling element housing recess provided on the support body so that the large-diameter rolling element can freely roll And a large-diameter rolling element is sealed with a solid lubricant.

In the seismic isolation device having this configuration, the ground vibration is attenuated by the rolling of the rolling element between the base plate and the support body, and the transmission of the vibration to the support body and the structure supported thereon is suppressed. In addition, the small-diameter rolling element comes into contact with the upper part of the large-diameter rolling element and rolls and circulates so that the large-diameter rolling element rotates smoothly, rolling friction resistance is reduced, and excellent seismic isolation is exhibited. .
The gap between the opening periphery of the large-diameter rolling element housing recess into which the large-diameter rolling element fits freely and the large-diameter rolling element is sealed with a solid lubricant. The friction resistance between the large-diameter rolling element, the peripheral edge of the opening, and the small-diameter rolling element is suppressed to maintain smooth rolling of the large-diameter rolling element, and the rust prevention effect by the rust prevention action of the lubricant is obtained. In addition, sealing with solid lubricant prevents foreign matter from entering the large-diameter rolling element housing recess from the outside, and does not cause rolling defects of the large-diameter rolling element and small-diameter rolling element due to the biting of foreign matter. Rolling is maintained. As described above, the sealing with the solid lubricant can simultaneously obtain both functions of lubrication and prevention of intrusion of foreign matters, and can provide lubrication, rust prevention and foreign matter intrusion prevention functions with a simple configuration.

  In this invention, you may attach to the said support body the sealing member which seals the clearance gap between the opening periphery of the said large diameter rolling element accommodation recessed part, and a large diameter rolling element located in the outer side of the said solid lubricant. By using such a seal member in combination, it is possible to more effectively prevent entry of foreign matter from the outside, and emulsification due to contact with moisture of the solid lubricant even in an environment where water easily enters. It is prevented, and lubrication and the extension of a seal life can be aimed at.

  The seismic isolation device according to the present invention includes a base plate, a support body positioned above the base plate, one large-diameter rolling element and a plurality of small-diameter rolling elements that are interposed between the base plate and the support body in a freely rolling manner. A spherical rolling surface that supports the plurality of small-diameter rolling elements in an aligned state along the upper surface of the large-diameter rolling element, and a peripheral edge of the rolling surface. In the seismic isolation device provided with a circulation path for circulating the small-diameter rolling element on the rolling surface, the peripheral edge of the opening of the large-diameter rolling element housing recess provided on the support body so that the large-diameter rolling element can freely roll The gap between the rolling element and the large-diameter rolling element is sealed with a solid lubricant, so that the rolling element can maintain smooth rolling due to lubrication and the rust prevention effect of the applied lubricant, and foreign matter can enter from outside. For many years on rolling bearings It is possible to maintain that excellent seismic isolation function.

  When the sealing member that seals the clearance between the opening peripheral edge of the large-diameter rolling element housing recess and the large-diameter rolling element is attached to the support body and is located outside the solid lubricant, the sealing function is While being made more effective, emulsification due to contact of the solid lubricant with moisture can be prevented, and lubrication and extension of the seal life can be achieved.

  An embodiment of the seismic isolation device of the present invention will be described with reference to FIG. The seismic isolation device 1 includes a base plate 2, a support body 3 positioned above the base plate 2, and a large-diameter rolling element including a single steel ball that is interposed between the base plate 2 and the support body 3 so as to freely roll. 4 and a small-diameter rolling element 5 composed of a plurality of steel balls. The upper surface of the base plate 2 is a rolling surface 2a that supports the large-diameter rolling element 4 so that it can roll. The bearing body 3 includes a spherical rolling surface 6 that supports the plurality of small-diameter rolling elements 5 so as to be able to roll in an aligned state along the upper surface of the large-diameter rolling element 4, and the rolling surfaces 6. A circulation path 7 that circulates the small-diameter rolling element 5 on the rolling surface 6 is provided following the peripheral edge.

  The rolling surface 6 and the circulation path 7 are configured by attaching a rolling element receiver 8 and a rolling element presser 9 to the support body 3 a of the support body 3. The support body 3 includes the support body main body 3 a, the rolling element receiver 8, and the rolling element presser 9. The rolling element receiver 8 is attached to the support body 3a by a protruding portion 8a protruding in the center of the upper surface. The rolling element presser 9 is fitted into a hollow portion opened on the lower surface of the support body 3a, and is fixed to the support body 3a by a retaining ring (not shown). The rolling element receiver 8 is a member whose inner and outer surfaces are formed in a spherical shape concentric with the center of the large-diameter rolling element 4 and whose spherical inner surface becomes the rolling surface 6. The circulation path 7 is formed between the spherical outer surface of the rolling element receiver 8 and the spherical inner surface of the support body 3a facing the outer surface. The rolling element presser 9 is a ring-shaped member in which a small-diameter rolling element guide surface 9a having an arcuate cross section facing obliquely upward is formed facing the peripheral edge of the rolling element receiver 8, and the small-diameter rolling element guide surface 9a causes The small diameter rolling element 5 is guided between the running surface 6 and the circulation path 7. The small-diameter rolling element 5 circulates while rolling along the rolling surface 6 and the circulation path 7 around the rolling element receiver 8, thereby smoothly rotating the large-diameter rolling element 4, and the base plate 2 and the large-diameter rolling element. The rolling friction resistance between the moving bodies 4 is reduced.

  The opening peripheral edge of the large-diameter rolling element housing recess 9b of the rolling element presser 9 is formed in a step shape to form a seal groove 9c, and the solid lubricant 10 is sealed in the seal groove 9c. As the solid lubricant 10, a solid lubricant composition for bearings or the like can be used.

  As the composition used as the solid lubricant 10, a composition comprising a polymer material and grease can be used. As a composition composed of such a polymer material and grease, for example, 95 wt% to 1 wt% of ultrahigh molecular weight polyethylene having an average molecular weight of 1 × 10 5 to 5 × 106 and a dropping point higher than the melting temperature of the ultrahigh molecular weight polyethylene are used. A composition comprising 5 wt% to 99 wt% of a lubricating grease (including an additive containing an additive that suppresses oil bleeding), heated to the melting temperature of the ultrahigh molecular weight polyethylene, cooled and solidified Alternatively, a mixture of 95 wt% to 1 wt% of low molecular weight polyethylene having an average molecular weight of 2 × 10 3 to 1 × 105 and 5 wt% to 99 wt% of lubricating grease having a dropping point higher than the melting temperature of the low molecular weight polyethylene is reduced to A composition obtained by heating to the melting temperature of molecular weight polyethylene and cooling to solidify (both disclosed in Patent Document 1) and the like are employed.

  A product of this type of solid lubricant 10 is polylube LP03, a heat-solidifying lubricant composition manufactured by NTN. In the case of using the heat solidifying lubricant composition as described above as the solid lubricant 10, the solid lubricant 10 is fired after being sealed in the seal groove 9 c.

  According to the seismic isolation device 1 having this configuration, the gap between the opening periphery of the large-diameter rolling element housing recess 9b and the large-diameter rolling element 4 is sealed with the solid lubricant 10, so that the large-diameter rolling element 4 by lubrication is Smooth rolling can be maintained, and intrusion of foreign matter from the outside can be prevented, and an excellent seismic isolation function by rolling support can be maintained for many years.

  Normally, if a large amount of grease is filled (for example, close to 100% with respect to the space volume), the rolling property of the rolling bearing portion is lowered. However, since the lubricant oozes from the solid lubricant, the solid lubricant 10 is applied to the extent. Is continuously supplied into the large-diameter rolling element housing recess 9b. The solid lubricant 10 is in sliding contact with the large-diameter rolling element 4, and the lubricant is supplied to the surface of the large-diameter rolling element 4 and lubricated. The lubricant supplied to the inside of the large-diameter rolling element housing recess 9b and the surface of the large-diameter rolling element 4 is also transferred to the small-diameter rolling element 5, and the small-diameter rolling element 5 is also lubricated. As a result, the maintenance period for the purpose of confirming the lubricant can be extended, and a long-term antirust effect can be obtained. Moreover, since the sealing function of the large diameter rolling element accommodation recessed part 9b which comprises the accommodating part of the rolling elements 4 and 5 in the seismic isolation apparatus 1, the circulation path 7, and the rolling surface 6 improves, life extension of these parts is possible. It becomes.

  In this way, by using the solid lubricant 10 for lubrication, there is no risk of soil contamination due to grease leakage, and there is no risk of lubricant leakage that may occur during grease lubrication. It can stably suppress the shaking of the building during an earthquake.

  FIG. 2 shows another embodiment of the seismic isolation device of the present invention. In this seismic isolation device 1, a seal member 11 that is located outside the solid lubricant 10 and seals the gap between the seal groove 9 c and the large-diameter rolling element 4 at the opening periphery of the large-diameter rolling element-receiving recess 9 b. Is attached to the rolling element presser 9. The seal member 11 is made of a rubber material or the like, and the peripheral wall of the seal groove portion 9c extends downward. The inner peripheral edge portion of the seal member attachment groove 9d formed in the extended peripheral wall portion has a large diameter rolling element. 4 is slidably in contact with the surface of 4 and in contact with the lower end surface of the solid lubricant 10.

  By using this seal member 11 in combination with the solid lubricant 10, water can be prevented from entering the large-diameter rolling element housing recess 9b even during floods such as flooding under the floor. Furthermore, if the solid lubricant 10 and water contact during such immersion, the solid lubricant 10 may be emulsified, but the contact between the solid lubricant 10 and water is reduced by the seal member 11, and such a concern Is wiped out. Since the other configuration is the same as that of the embodiment shown in FIG. 1, common portions are denoted by the same reference numerals and description thereof is omitted.

  FIG. 3 shows an example of use of the seismic isolation device 1 having the above configuration. The seismic isolation device 1 according to any one of the above embodiments is interposed at a plurality of locations between the lower pedestal 20 on the ground side and the upper pedestal 21 that supports a structure (not shown) such as a building. The

  As the solid lubricant 10, other solid lubricants having lubricity and sealing properties can be used in addition to the above-described composition. The rolling surface 2a of the base plate 2, the large and small rolling elements 4 and 5, the bearing body 3a constituting the bearing body 3, the rolling element receiver 8, and the rolling element presser 9 are subjected to known surface treatment for rust prevention. It is desirable that

It is sectional drawing which shows one Embodiment of the seismic isolation apparatus of this invention. It is sectional drawing which shows other embodiment of the seismic isolation apparatus of this invention. It is a front view which shows the usage example of the seismic isolation apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Seismic isolation device 2 ... Base plate 3 ... Bearing body 4 ... Large diameter rolling element 5 ... Small diameter rolling element 6 ... Rolling surface 7 ... Circulation path 9b ... Large diameter rolling element accommodation recessed part 9c ... Seal groove part (opening periphery)
10 ... Solid lubricant 11 ... Sealing member

Claims (2)

A base plate, a support body positioned above the base plate, and one large-diameter rolling element and a plurality of small-diameter rolling elements interposed between the base plate and the support body so as to be freely rollable. A spherical rolling surface that supports the plurality of small-diameter rolling elements in an arrayed state along the upper surface of the large-diameter rolling element, and a small diameter of the rolling surface following the periphery of the rolling surface. In a seismic isolation device with a circulation path for circulating rolling elements,
The gap between the opening peripheral edge of the large-diameter rolling element housing recess and the large-diameter rolling element, which is provided on the support body and in which the large-diameter rolling element fits freely, is sealed with a solid lubricant. Seismic isolation device. 2. The seismic isolation system according to claim 1, wherein a seal member that is located outside the solid lubricant and that seals a gap between an opening peripheral edge of the large-diameter rolling element housing recess and the large-diameter rolling element is attached to the support body. apparatus.

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