Vibration-proof structure

Abstract

To provide a vibration-proof structure capable of lowering a floor part when adjusting the height of the floor part.SOLUTION: In a vibration-proof structure, a floor part height adjusting part 6 has a push-up adjusting part 61 for pushing up a floor part 3 and a pull-down adjusting part 62 for pulling down the floor part 3; the pull-down adjusting part 62 has a floor part fixing frame 63 fixed to the floor part 3, a structure fixing frame 64 fixed to a structure 2 and positioned above the floor part fixing frame 63, and a jack 65 disposed between the floor part fixing frame 63 and the structure fixing frame 64; the jack 65 has a cylinder part 67 fixed to the floor part fixing frame 63 (first frame) and a piston part 68 inserted into the cylinder part 67 from the structure fixing frame 64 (second frame) side and displaceable in the vertical direction with respect to the cylinder part 67; the upper end part (an end part on the structure fixing frame 64 side, an end part on the second frame side) of the piston part 68 is disposed so as to face the structure fixing frame 64 in the vertical direction, and comes into contact with the structure fixing frame 64 when the jack 65 extends.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a vibration isolation structure.

Background Art

[0002] In facilities such as music live halls and dance studios, vertical vibrations (so-called vertical vibrations) caused by the bending and stretching movements of a large number of guests may occur. To cope with this, a vibration isolation structure in which the floor portion of the relevant part is a floating floor insulated from the structural body is known (see, for example, Patent Document 1). In such a vibration isolation structure, the structural body is partially recessed, and a floor portion supported by a spring is provided in the recessed portion. The floating floor is configured to be relatively displaceable in the vertical direction with respect to the structural body due to the displacement of the spring.

[0003] The magnification of the reaction force with respect to the excitation force is the "reaction force reduction ratio". Since the larger the excitation vibration frequency with respect to the natural vibration frequency f1 of the floating floor, the smaller the reaction force reduction ratio (the higher the vibration isolation effect), the weight of the floating floor can be increased or the spring stiffness can be decreased. However, increasing the weight increases the cost, and decreasing the spring stiffness results in a so-called soft spring state. Therefore, in the floating floor of the vibration isolation structure that has been put into practical use, a huge RC floor slab with a thickness of about 1 m is used to make the floor self-weight (m×g, g is the gravitational acceleration) more than 10 times the excitation force, and the natural vibration frequency is about 1 Hz. As a result, the vertical displacement during normal use is kept at about 2 cm or less.

[0004] When using a facility with a vibration isolation structure provided with a floor section that serves as a floating floor as described above for purposes other than live performances or dancing (for example, exhibitions, sports events, etc.), there is a need to make the floor section a fixed floor with no vertical displacement instead of spring-supported. Thus, a mechanism that can arbitrarily switch the floor section between a floating floor with high vibration isolation effect and a fixed floor without vertical displacement according to the purpose of use of the facility is desired. It is conceivable to manually lock the support springs (make the support springs rigid) to make a fixed floor, but the operation of manually locking all the support springs in the pit below the floor section is time-consuming and not practical. Therefore, the applicant has filed an application for a vibration isolation structure having a locking mechanism that can lock or release the vertical displacement of the floor section by remote control (Japanese Patent Application No. 2020-117814).

[0005] The above locking mechanism is provided in parallel with the support springs between the floor section and the structural body. The locking mechanism has a jack that is supported by the structural body and expands and contracts in the vertical direction. When the floor section is a floating floor, the jack is separated from the floor section to make the floor section displaceable in the vertical direction with respect to the structural body. When the floor section is a fixed floor, the jack is pressed against the floor section from below to restrain the downward displacement of the floor section. In such a vibration isolation structure having a locking mechanism, when using the floor section as a fixed floor, the height of the floor section can be adjusted by adjusting the length of the jack while pressing the jack against the floor section from below.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, in the above anti-vibration structure, when adjusting the height of the floor part, the floor part can be pushed up, but cannot be pulled down. Therefore, when the height of the floating floor is lower than the predetermined height, it can be dealt with, but when it is higher, it cannot be dealt with.

[0008] Therefore, an object of the present invention is to provide an anti-vibration structure capable of pulling down the floor part when adjusting the height of the floor part.

Means for Solving the Problems

[0009] To achieve the above object, the anti-vibration structure according to the present invention includes a structure, a floor part provided on the structure, a support spring that connects the structure and the floor part and supports the floor part so as to be displaceable in the vertical direction with respect to the structure, a lock mechanism that is arranged in parallel with the support spring and can switch between restraining and allowing the vertical displacement of the floor part with respect to the structure, and a floor part height adjuster that adjusts the height of the floor part with respect to the structure. The floor part height adjuster includes a lifting adjuster that pushes up the floor part and a lowering adjuster that pulls down the floor part. The lowering adjuster includes a floor part fixing pedestal fixed to the floor part, a structure fixing pedestal fixed to the structure and located above the floor part fixing pedestal, and a jack arranged between the floor part fixing pedestal and the structure fixing pedestal. The jack includes a cylinder part fixed to a first pedestal that becomes either the floor part fixing pedestal or the structure fixing pedestal, and a piston part that is inserted into the cylinder part from the side of the second pedestal that becomes the other of the floor part fixing pedestal and the structure fixing pedestal and is displaceable in the vertical direction with respect to the cylinder part. The end of the piston part on the second pedestal side is arranged vertically opposite to the second pedestal, and when the piston part is pulled out of the cylinder part and the jack extends, it contacts the second pedestal.

[0010] In the present invention, by extending the jack provided between the floor fixing base and the structure fixing base of the lowering adjustment unit to widen the distance between the floor fixing base and the structure fixing base, the floor fixing base can be moved downward with respect to the structure fixing base. Thus, by extending the jack, the floor fixed to the floor fixing base can be lowered downward.

[0011] Further, in the vibration isolation structure according to the present invention, the jack may be an electric jack that can be remotely operated.

[0012] With such a configuration, it is not necessary to adjust the height of the floor in the space (underfloor pit) between the structure and the floor, and it can be performed from above the floor or from a position away from the floor. Therefore, even when the space between the structure and the floor is dark and narrow, it is not necessary to work in such a space.

[0013] Further, in the vibration isolation structure according to the present invention, the lowering adjustment unit may have a sensor capable of measuring the distance between the structure and the floor, and when the distance between the structure and the floor measured by the sensor reaches a predetermined value, the driving of the jack may be stopped.

[0014] With such a configuration, the height of the floor can be easily adjusted.

[0015] Further, in the vibration isolation structure according to the present invention, the jack has a worm screw that rotates a worm wheel, and a screw shaft that moves up and down when the rotation of the worm screw is transmitted through the worm wheel, and the screw shaft is a screw jack that serves as the piston portion, and the screw shaft may be a trapezoidal screw.

[0016] With such a configuration, by using a trapezoidal screw for the screw shaft of the screw jack, the self-locking function works, and it is only necessary to drive the motor when moving the jack up and down. Otherwise, the floor can be held in position without displacement due to the load acting on the floor without driving the motor.

[0017] Further, in the vibration isolation structure according to the present invention, the jack has a worm screw for rotating a worm wheel, and a screw shaft that moves up and down when the rotation of the worm screw is transmitted through the worm wheel, and the screw shaft is a screw jack that serves as the piston portion, and the screw shaft may be a ball screw.

[0018] With such a configuration, it is possible to reduce the friction between the screw shaft and the ball nut integrated with the worm wheel, and it is possible to raise and lower the screw shaft (piston portion) efficiently and accurately.

[0019] Further, in the vibration isolation structure according to the present invention, the jack may be a hydraulic jack.

[0020] With such a configuration, it is possible to raise and lower the piston portion efficiently. In this case, a check valve can be provided in the hydraulic hose of the hydraulic jack to impart a self-locking function.

Effects of the Invention

[0021] According to the present invention, when adjusting the height of the floor portion, the floor portion can be pulled down.

Brief Description of the Drawings

[0022]

Figure 1

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Figure 13

Mode for Carrying Out the Invention

[0023] (First Embodiment) Hereinafter, the vibration isolation structure according to the embodiment of the present invention will be described with reference to FIGS. 1-9. As shown in FIG. 1, the vibration isolation structure 1 according to the present embodiment includes a structure 2, a bed part 3 installed above the structure 2, a support spring 4 provided between the structure 2 and the bed part 3, a lock mechanism 5 provided between the structure 2 and the bed part 3, and a bed height adjustment part 6 for adjusting the height of the bed part 3 with respect to the structure 2. The support spring 4 has its spring axis direction as the vertical direction and connects the structure 2 and the bed part 3. The support spring 4 supports the bed part 3 so as to be vertically displaceable (vibratable) with respect to the structure 2. The lock mechanism 5 is configured to be able to restrain the vertical displacement of the bed part 3 with respect to the structure 2. The support spring 4, the lock mechanism 5, and the bed height adjustment part 6 are provided in parallel between the structure 2 and the bed part 3.

[0024] The anti-vibration structure 1 according to this embodiment is adopted, for example, in a building such as a large hall, and is assumed to have people and objects placed on the floor portion 3. When this building is used for a music live, dance, etc., when the floor portion 3 is excited by a large number of guests bending and stretching in accordance with the music at the upper part of the floor portion 3, it is used as a floating floor where vertical vibration (so-called vertical vibration) occurs in the floor portion 3. Further, when this building is used for an exhibition, a sports event, etc., it is used as a fixed floor where the floor portion 3 does not vibrate vertically.

[0025] The structure 2 is constructed of RC, for example, such as a foundation. In this embodiment, the structure 2 has a recess 21 that opens upward. The structure 2 has a bottom plate portion 22 located below the recess 21 and a side wall portion 23 located on the side of the recess 21 and extending upward from the peripheral edge of the bottom plate portion 22. The upper surface of the bottom plate portion 22 is formed as a horizontal plane. A plurality of support springs 4 and lock mechanisms 5 are provided on the bottom plate portion 22.

[0026] The floor portion 3 is formed in a flat plate shape and is disposed in the recess 21 of the structure 2 with the plate surface facing the horizontal plane. The floor portion 3 is disposed above the bottom plate portion 22 with a gap therebetween. Support springs 4 and lock mechanisms 5 are provided between the bottom plate portion 22 and the floor portion 3. The plurality of support springs 4 are provided in parallel at intervals in the horizontal direction. The plurality of support springs 4 connect the bottom plate portion 22 and the floor portion 3.

[0027] The lock mechanism 5 has a jack 51, a sensor 52 attached to the jack 51, and a control unit (not shown) that controls the operation of the jack 51. A plurality of jacks 51 are provided. In this embodiment, the jacks 51 are disposed in the vicinity of each of the plurality of support springs 4. The control unit is configured to be able to control the plurality of jacks 51 simultaneously. The sensor 52 is provided for each of the plurality of jacks 51.

[0028] The jack 51 is a remotely operable electric jack. The jack 51 has a cylinder part 53 fixed to the bottom plate part 22 of the structure 2 and a piston part 54 that can be displaced (lifted and lowered) in the vertical direction with respect to the cylinder part 53. The piston part 54 is inserted into the cylinder part 53 from above. In the present embodiment, an RC rising part 24 is provided on the bottom plate part 22, and a hole part 25 that opens upward is provided in this rising part 24. The cylinder part 53 is inserted into the hole part 25 with the axial direction being the vertical direction and the lower side.

[0029] When the piston part 54 moves upward with respect to the cylinder part 53, the length inserted into the cylinder part 53 decreases. When the piston part 54 moves downward with respect to the cylinder part 53, the length inserted into the cylinder part 53 increases. In FIG. 1, the piston part 54 moves upward with respect to the cylinder part 53, and the upper end part of the piston part 54 is in contact with the lower surface of the floor part 3. When the piston part 54 moves downward with respect to the cylinder part 53, the upper end part of the piston part 54 moves away from the lower surface of the floor part 3.

[0030] When the piston part 54 is in the raised position and in contact with the floor part 3, the downward displacement of the floor part 3 in the vertical direction with respect to the structure 2 is restricted. That is, the floor part 3 becomes a fixed floor, similar to the case where a shoring is installed under the floor. When the piston part 54 is in the lowered position and away from the floor part 3, the floor part 3 can be displaced in the vertical direction with respect to the structure 2, similar to the case where the shoring is removed. That is, the floor part 3 becomes a floating floor. When the floor part 3 becomes a fixed floor, since the vertical rigidity of the jack 51 is far greater than the vertical rigidity of the support spring 4, the piston part 54 will bear the subsequent load (loading load) of the floor part 3 and the people and objects on the floor part 3. Although not shown, a plate may be attached to the upper end surface of the piston part 54, and a rubber sheet for unevenness may be attached thereon.

[0031] The sensor 52 detects that the upper end of the piston portion 54 has come into contact with the lower surface of the floor portion 3. The sensor 52 is, for example, a contact sensor using a microswitch. The control unit is configured to stop the upward movement of the piston portion 54 when the sensor 52 detects that the upper end of the piston portion 54 has come into contact with the floor portion 3. With such a configuration, it is possible to make the jack 51 bear the load applied on the floor portion 3 while most of the self-weight of the floor portion 3 is borne by the support spring 4. If the load (loading load) applied on the floor portion 3 is assumed to be less than about 1 / 10 of the self-weight of the floor portion 3, the capacity of the jack 51 can be small. Also, if the microswitch of the sensor 52 is exposed on the outer peripheral surface, it can be easily replaced even if the microswitch fails by any chance.

[0032] The switching between the floating floor and the fixed floor of the floor portion 3 by the locking mechanism 5 may be performed before the event is held in the hall where the vibration isolation structure 1 is adopted, so there is no need to operate the jack 51 at high speed. Also, since there is almost no loading load during the switching, the load force when moving the jack 51 is small. Therefore, the capacity of the motor can be small, resulting in low cost.

[0033] The floor height adjustment unit 6 has a lifting adjustment unit 61 that pushes up the floor portion 3 and a lowering adjustment unit 62 that pulls down the floor portion 3. In the present embodiment, the jack 51 of the locking mechanism 5 also serves as the lifting adjustment unit 61. The lifting adjustment unit 61 can adjust the height of the floor portion 3 by raising the piston portion 54 of the jack 51 to push up the floor portion 3. When pushing up the floor portion 3, a load acts on the jack 51, but the amount pushed up for adjustment is small, and the jack load force is also small.

[0034] The lowering adjustment unit 62 includes a floor fixing pedestal 63 fixed to the floor portion 3, a structure fixing pedestal 64 fixed to the structure 2, a jack 65 disposed between the floor fixing pedestal 63 and the structure fixing pedestal 64, a control unit (not shown) that controls the operation of the jack 65, and a sensor 66 capable of measuring the distance between the structure 2 and the floor portion 3. The control unit is configured to be able to control a plurality of jacks 65 simultaneously. The floor fixing pedestal 63, the structure fixing pedestal 64, and the jack 65 are set as a set, and a plurality of such sets are provided between the structure 2 and the floor portion 3. The above-mentioned set is disposed in the vicinity of each of the plurality of support springs 4 between the structure 2 and the floor portion 3. The control unit is configured to be able to control a plurality of jacks 65 simultaneously. The sensor 66 is provided in the vicinity of each of the plurality of jacks 65. With such a configuration, in the vibration isolation structure 1 according to the present embodiment, regardless of the amount of settlement of the floor portion 3 due to the loading weight, it becomes a system that can maintain the position at an arbitrary height. Therefore, for example, when holding an event performance such as a live show, the floor portion 3 is made into a floating floor to suppress the vertical vibration, and when holding an exhibition or the like, the floor portion 3 is made into a fixed floor to eliminate the sinking and sticking of the floor portion 3, and it is possible to eliminate the step between the floor of the structure 2 around the floor portion 3 (floating floor).

[0035] As shown in FIGS. 1 to 3, the floor fixing pedestal 63 is made of, for example, a section steel. The floor fixing pedestal 63 has a floor fixing portion 631 that protrudes downward from the lower surface of the floor portion 3, and a jack installation portion 632 that protrudes horizontally from the lower end portion of the floor fixing portion 631. The floor fixing portion 631 extends in the vertical direction, and the upper end portion is fixed to the lower surface of the floor portion 3. Two floor fixing portions 631 are provided at intervals in the horizontal direction. This horizontal direction is defined as the X direction, and the horizontal direction orthogonal to the X direction is defined as the Y direction.

[0036] The jack installation part 632 extends in the X direction, with one end in the X direction joined to the lower end of one floor fixing part 631 and the other end joined to the lower end of the other floor fixing part 631. That is, the jack installation part 632 is installed between the lower ends of the two floor fixing parts 631 respectively. The jack installation part 632 is located above the upper surface of the structure 2 with a certain interval. The jack installation part 632 is arranged at a height where it will not contact the structure 2 even if the floor part 3 becomes a floating floor and descends. The upper surface of the jack installation part 632 is a horizontal plane. The floor fixing gantry 63 is U-shaped and opens upward when viewed from the Y direction.

[0037] The structure fixing gantry 64 is made of, for example, section steel. The structure fixing gantry 64 has a structure fixing part 641 that protrudes upward from the upper surface of the structure 2 and a jack contact part 642 that protrudes horizontally from the upper end of the structure fixing part 641. The structure fixing part 641 extends in the vertical direction, and its lower end is fixed to the upper surface of the structure 2. Two structure fixing parts 641 are provided at intervals in the Y direction. The jack contact part 642 extends in the Y direction, with one end in the Y direction joined to the upper end of one structure fixing part 641 and the other end joined to the upper end of the other structure fixing part 641. That is, the jack contact part 642 is installed between the upper ends of the two structure fixing parts 641 respectively. The jack contact part 642 is located below the lower surface of the floor part 3 with a certain interval. The jack contact part 642 is arranged at a height where it will not contact the floor part 3 even if the floor part 3 becomes a floating floor and descends. The lower surface of the jack contact part 642 is a horizontal plane. The structure fixing gantry is U-shaped and opens downward when viewed from the X direction.

[0038] The jack installation part 632 is located below the jack contact part 642. The upper surface of the jack installation part 632 and the lower surface of the jack contact part 642 face each other with a gap in the vertical direction. As described above, the direction in which the jack installation part 632 extends and the direction in which the jack contact part 642 extends are perpendicular to each other. The two structure fixing parts 641 of the structure fixing base 64 are arranged at positions sandwiching the jack contact part 642 from the Y direction. The two floor fixing parts 631 of the floor fixing base 63 are arranged at positions sandwiching the jack installation part 632 from the X direction.

[0039] The jack 65 is a remotely operable electric jack. The jack 65 has a cylindrical cylinder part 67 and a rod-shaped piston part 68 coaxially inserted into the cylinder part 67. The axis direction of the jack 65 is the vertical direction, and the piston part is arranged in a direction in which it is inserted into the cylinder part 67 from above. When the piston part 68 moves upward with respect to the cylinder part, the length inserted into the cylinder part 67 decreases, and when it moves downward with respect to the cylinder part 67, the length inserted into the cylinder part 67 increases. The state where the piston part 68 moves upward with respect to the cylinder part 67 is defined as the extended state, and the state where the piston part 68 moves downward with respect to the cylinder part 67 is defined as the retracted state. The cylinder part 67 is fixed to the jack installation part 632. In this embodiment, the jack installation part 632 is a square tube-shaped section steel with a BOX cross-section. A hole is formed in the jack installation part 632 that penetrates the upper surface in the vertical direction and communicates with the inside. The lower side of the cylinder part 67 is inserted into the above hole. The upper end part of the piston part 68 is arranged to face the lower surface of the jack contact part 642 in the vertical direction. A plate may be attached to the upper end surface of the piston part 68, and a rubber sheet for coping with unevenness may be attached thereon.

[0040] As shown in FIGS. 1-4, when the piston portion 68 moves upward with respect to the cylinder portion 67, the upper end contacts the lower surface of the jack contact portion 642. The jack 65 is in a tensioned state between the jack installation portion 632 and the jack contact portion 642 when the cylinder portion 67 is pressed against the lower surface of the jack contact portion 642. When the jack 65 is in such a state, the jack installation portion 632 cannot displace upward with respect to the jack contact portion 642, that is, in the approaching direction. As a result, the upward displacement of the floor portion 3 provided with the jack installation portion 632 with respect to the structure 2 provided with the jack contact portion 642 is restricted. Note that even when the jack 65 is in a tensioned state between the jack installation portion 632 and the jack contact portion 642, if the jack 65 of the locking mechanism 5 does not push up the floor portion 3, the floor portion 3 can be displaced downward. That is, even if the jack 65 is in a tensioned state between the jack installation portion 632 and the jack contact portion 642 before a spectator or the like is loaded on the floor portion 3, when the floor portion 3 vibrates up and down, the floor portion 3 sinks due to the load by a spectator or the like and the jack 51 of the locking mechanism 5 does not enter a tensioned state, and the jack 51 of the locking mechanism 5 does not push up the floor portion 3. In this case, no load acts on all the jacks and the locking mechanism 5 does not function. Therefore, the floor portion 3 can be used as a floating floor.

[0041] When the jack 65 further extends in a tensioned state between the jack installation portion 632 and the jack contact portion 642, the jack installation portion 632 moves downward with respect to the jack contact portion 642. As a result, the floor portion 3 moves downward toward the structure 2 side. The lowering adjustment portion 62 can lower the floor portion 3 by extending the jack 65.

[0042] The lowering adjustment portion 62 of the present embodiment has a sensor 66 capable of measuring the distance between the structure 2 and the floor portion 3. The lowering adjustment portion 62 is configured to stop driving the jack 65 when the distance between the structure 2 and the floor portion 3 measured by the sensor 66 reaches a predetermined value.

[0043] The lowering adjustment part 62 applies a downward force to the floating floor to hold it in a predetermined position. However, when the loading weight increases and exceeds the force applied to the jack 65, the reaction force of the jack 65 becomes zero, and the floating floor (floor part 3) will sink. Therefore, when the loading weight increases around the lowering adjustment part 62 and the sinking of the floating floor may become a problem, it is desirable to use the lifting adjustment part 61 in combination.

[0044] The vibration isolation structure of this embodiment is obtained by adding a fixing mechanism to the conventional floating floor. When neither the lowering adjustment part 62 nor the lifting adjustment part 61 acts, the floating floor and the foundation of the structure 2 are completely insulated without axial force transmission through the jacks 51 and 65. Therefore, there is no risk that the mechanism including the jacks 51 and 65 will have an adverse effect on the vibration isolation performance.

[0045] As shown in FIG. 5, the jack 65 is a screw jack 7. The screw jack 7 (jack 65) includes a worm wheel 71, a worm screw 72 that rotates the worm wheel 71, a screw shaft 73 that moves up and down when the rotation of the worm screw 72 is transmitted through the worm wheel 71, and a housing 74 that houses and supports these components. The housing 74 corresponds to the cylinder part 67 of the jack 65, and the screw shaft 73 corresponds to the piston part 68 of the jack 65. The housing 74 is fixed to the rising part 24 (see FIG. 1) of the bottom plate part 22. The screw shaft 73 is rotationally constrained while being screwed with a nut integrated with the worm wheel 71.

[0046] The worm screw 72 is a rod-shaped screw having a thread 72a formed on its outer peripheral surface. The worm screw 72 is arranged in a direction extending horizontally. That is, the axis of the worm screw 72 is a horizontal axis extending in the horizontal direction. The worm screw 72 is connected to a motor 75 and rotates around its axis by the drive of the motor 75. The operation of the motor 75 can be remotely controlled. The worm screw 72 is rotatable around its axis with respect to the housing 74, but its displacement in the axial direction is constrained.

[0047] The worm wheel 71 is formed in a cylindrical shape having a hole portion 71a at the central portion. Threads 71b and 71c are formed on the outer peripheral surface and the inner peripheral surface of the worm wheel 71, respectively. The worm wheel 71 is arranged in a direction in which the axis extends in the vertical direction. That is, the axis of the worm wheel 71 is a vertical axis. The thread (gear) 71b on the outer peripheral surface of the worm wheel 71 is screwed with the thread 72a of the worm screw 72. The worm wheel 71 is rotatable about the axis with respect to the housing 74, but the displacement in the axial direction is restricted.

[0048] The screw shaft 73 is a rod-shaped screw having a thread 73a formed on the outer peripheral surface. The thread 73a of the screw shaft 73 is a trapezoidal thread. The screw shaft 73 is arranged in a direction in which it extends in the vertical direction. That is, the axis of the screw shaft 73 is a vertical axis extending in the vertical direction. The screw shaft 73 is inserted into the hole portion 71a of the worm wheel 71 and is arranged coaxially with the worm wheel 71. The thread 73a on the outer peripheral surface of the screw shaft 73 is screwed with the thread (nut) 71c on the inner peripheral surface of the worm wheel 71. The screw shaft 73 is movable in the axial direction with respect to the housing 74, but the rotation about the axis is restricted. As a method of restricting rotation, it is put into practical use by making the lower end of the screw shaft into a square shape larger than the shaft diameter and sliding it inside the cylindrical portion 67 with a square shape, or by providing an axial guide groove in the screw shaft and sliding it with a guide portion integrated with the housing 74.

[0049] When such a screw jack 7 is driven by the motor 75, as shown in FIG. 6, when the worm screw 72 rotates about the horizontal axis, the meshing worm wheel 71 rotates about the vertical axis. At this time, since the rotational speed of the worm wheel 71 is extremely small compared to the rotational speed (rotation speed) of the worm screw 72, a torque several tens of times that of the worm screw 72 is generated in the worm wheel 71. Returning to Fig. 5, when the worm wheel 71 rotates about the vertical axis, the screw shaft 73, whose rotation about the vertical axis is restricted, moves in the vertical direction. That is, since the screw shaft 73 is the piston part 68, when the motor 75 is driven, the piston part 68 moves up and down.

[0050] Next, the operation and effects of the vibration isolation structure 1 according to the above-described embodiment will be described. In the vibration isolation structure 1 according to the above-described embodiment, the jack 65 provided between the floor fixing base 63 and the structure fixing base 64 of the lowering adjustment part 62 is extended to widen the distance between the floor fixing base 63 and the structure fixing base 64, whereby the floor fixing base 63 can be moved downward with respect to the structure fixing base 64. In this way, by extending the jack 65, the floor part 3 fixed to the floor fixing base 63 can be pulled downward.

[0051] Further, in the vibration isolation structure according to the present invention, the jack 65 may be an electric jack that can be remotely operated.

[0052] With such a configuration, it is not necessary to adjust the height of the floor part 3 in the space (under-floor pit) between the structure 2 and the floor part 3, and it can be performed from above the floor part 3 or from a position away from the floor part 3. Therefore, even when the space between the structure 2 and the floor part 3 is dark and narrow, there is no need to perform work in such a space.

[0053] Further, in the vibration isolation structure according to the present invention, the lowering adjustment part 62 has a sensor 66 capable of measuring the distance between the structure 2 and the floor part 3, and is configured such that the driving of the jack 65 stops when the distance between the structure 2 and the floor part 3 measured by the sensor 66 reaches a predetermined value. With such a configuration, the height of the floor part 3 can be easily adjusted. In the lowering adjustment part 62 of the present application, the distance between the lower surface of the floating floor and the upper surface of the foundation of the structure 2 is measured by the sensor 66, and when it reaches a predetermined dimension, the height level of the floating floor can be arbitrarily adjusted by stopping. A load is applied to the jack 65 to lower the floating floor. Since the set floating floor level is not lower than when the loading capacity is full, it can be said that the jack load-bearing capacity (endurance) is sufficient as long as it corresponds to the loading capacity. Note that the force acting on the lowering adjustment unit 62 (jack reaction force) decreases as the loading load applied to the floating floor increases.

[0054] In the state of the floating floor, the floor part 3 sinks slightly (for example, about 20 mm) due to the loading load of spectators and the like. There is a floor part 26 of the structure 2 at the outer peripheral part of the floor part 3, which is a fixed floor that does not sink. For this reason, it is common to provide an expansion joint corresponding to the step between the floor part 26 of the structure 2 and the floor part 3. Since it is more preferable that the above step is smaller, the level of the floor part 26 of the structure 2 is often set at the middle between the level of the floor part 3 when there is no loading load and the level of the floor part 3 when the loading load is full. In that case, when there is no loading load (when setting up the event venue), the floor part 3 becomes a level slightly higher than the floor part 26 of the structure 2 as shown in FIG. 7, and a step is generated. In FIG. 7, the configuration other than the arrangement of the lifting adjustment unit 61 (lock mechanism 5) and the lowering adjustment unit 62 in FIG. 1 is the same.

[0055] To eliminate this step, the following procedure can be adopted. In the state of the floor part 3 (initial state) of the floating floor without a loading load, it is at a position slightly higher than the floor part 26 of the structure 2. In this state, all the jacks 51 and 65 of the floor part height adjustment unit 6 are not operating, and the floor part 3 is supported only by the support spring 4 (the floor part 3 and the structure 2 are in a completely insulated state). Operate the jack 51 of the lowering adjustment unit 62 installed below the right end of the floor part 3 in FIG. 8 to lower the right end of the floor part 3. In this state, the lifting adjustment units 61 and 61 are not operating, and the floor part 3 will be slightly inclined (since the floor part 3 is lowered by about several millimeters, the inclination is less than 1 / 1000 and does not cause a problem). Align the right end of the floor part 3 with the level of the floor part 26 of the structure 2, and press and fix the jack 51 of the lifting adjustment unit 61 against the floor part 3. In this state, the right end of the floor part 3 and the floor part 26 of the structure 2 are at the same level, and the step is almost eliminated. As shown in FIG. 9, the rail 9 can be pulled out from above the floor portion 26 of the structure 2 to deploy the movable floor seat (roll-back). It becomes a fixed floor where the floor portion 3 does not displace even when the load changes. Here, only the right end of the floor portion 3 is leveled with the floor portion 26 of the structure 2, but it is not necessary to be limited to this, and the corners of the floor portion 3 or the entire circumference of the floor portion 3 can also be leveled with the floor portion 26 of the structure 2. Also, instead of completely aligning the level of the floor portion 3 with the floor portion 26 of the structure 2, a setting such as lowering the floor portion 3 by 5 mm with respect to the floor portion 26 of the structure 2 is also possible.

[0056] Further, in the vibration isolation structure 1 according to the present embodiment, the jack 51 has a worm screw 72 that rotates the worm wheel 71 and a screw shaft 73 that moves up and down when the rotation of the worm screw 72 is transmitted via the worm wheel 71, and the screw shaft 73 is a screw jack 7 that becomes the piston portion 68. And the thread 73a on the outer peripheral surface of the screw shaft 73 is a trapezoidal thread. In this way, by using a trapezoidal thread for the thread 73a of the screw shaft 73 of the screw jack 7, the self-locking function works, and it is only necessary to drive the motor 75 when moving the jack 51 up and down. Otherwise, the floor portion 3 can be held in position without displacement due to the load acting on the floor portion 3 without driving the motor 75.

[0057] Also, the trapezoidal thread used for the thread 73a of the screw shaft 73 (piston portion 68) has a low screw efficiency, so the self-locking function (self-holding function) works anywhere within the stroke. This means that because the friction of the thread is large, there is no risk of reverse operation (the thread rotating in the reverse direction due to the load) even when a load acts on the jack 65. Therefore, even when the load acting on the jack 65 changes, the jack 65 does not displace, and the merit of being able to support the load without moving in the vertical direction regardless of the height of the floor portion 3 is obtained.

[0058] (Second Embodiment) Next, other embodiments will be described with reference to the accompanying drawings. Members and parts that are the same as or similar to those in the above-described first embodiment will be denoted by the same reference numerals, and descriptions thereof will be omitted. Different configurations of the embodiments will be described. As shown in FIG. 10, in the vibration isolation structure 1B according to the second embodiment, a screw jack 7B is used for the jack 65B of the lowering adjustment portion 62B of the floor height adjustment portion 6B, and the screw shaft 73B is a ball screw. When the rotation of the worm screw 72 is transmitted to the screw shaft 73B via the worm wheel 71B, the screw shaft 73B moves up and down. A plurality of balls 76 are provided between the screw (ball screw) 73Ba on the outer peripheral surface of the screw shaft 73B and the screw (ball nut) 71Bc on the inner peripheral surface of the worm wheel 71B. The screw shaft 73B is rotationally restrained while being screwed with the ball nut integrated with the worm wheel 71B. In the second embodiment, the screw 73Ba on the outer peripheral surface of the screw shaft 73B is not a trapezoidal screw. The position where the lowering adjustment portion 62B is provided and the action of the lowering adjustment portion 62B are the same as those of the lowering adjustment portion 62 in the first embodiment. The cylinder portion is indicated by 67B in the figure.

[0059] In the vibration isolation structure according to the second embodiment, the same effects as those in the above-described first embodiment are achieved. Since the screw shaft 73B of the jack 65B is a ball screw, the friction between the screw shaft 73B and the screw (ball nut) 71Bc integrated with the worm wheel 71B can be reduced, and the screw shaft 73B (piston portion 68B) can be lifted and lowered efficiently and accurately. In addition, since the ball screw has a high screw efficiency, the loss is small and the load on the motor 75 can be reduced.

[0060] Note that, since the ball screw has a high screw efficiency, the worm screw 72B may rotate due to the load acting on the screw shaft 73B, and the screw shaft 73B may move (sink downward), and the self-locking mechanism may not work. Therefore, it is preferable to additionally provide a brake mechanism for preventing the rotation of the worm screw 72B. The brake mechanism may be provided on the motor.

[0061] (Third Embodiment) As shown in FIG. 11, in the vibration isolation structure 1C according to the third embodiment, a hydraulic jack 8 is used instead of a screw jack for the jack 65C of the lowering adjustment part 62C of the floor height adjustment part 6C. The hydraulic jack 8 (jack 65C) operates a hydraulic pump 81 to raise the piston part 68C, and is configured as a self-locking mechanism by providing a check valve 83 in a hose 82 connecting the hydraulic pump 81 and the hydraulic jack 8, and the piston part 68C is lowered by operating a solenoid valve 84 (relief valve) provided in the hose 82.

[0062] When raising the piston part 68C of the jack 65C, the motor 85 of the hydraulic pump 81 is driven to send the oil in the tank 86 to the hydraulic jack 8 through the check valve 83. When a limit switch provided in the hydraulic jack 8 is turned on (the jack 65C contacts the jack contact part 642), the hydraulic pump 81 is stopped. Since the oil does not flow back due to the check valve 83 even when the hydraulic pump 81 is stopped, the jack 65C does not move while holding the load. When lowering the piston part 68 of the jack 65C, the solenoid valve 84 (relief valve) is opened to return the oil to the tank 86. The position where the lowering adjustment part 62C is provided and the action of the lowering adjustment part 62C are the same as those of the lowering adjustment part 62 of the first embodiment. The cylinder part is indicated by 67C in the figure.

[0063] In the vibration isolation structure according to the third embodiment, the same effects as those of the above embodiment are achieved, and the piston part 68C can be efficiently raised and lowered. In the vibration isolation structure 1 according to the third embodiment, a self-locking function can be imparted by providing a check valve 83 in the hose 82.

[0064] As described above, the embodiments of the vibration isolation structure according to the present invention have been described, but the present invention is not limited to the above embodiments, and can be appropriately changed without departing from the spirit thereof. For example, in the above-described embodiment, a jack installation portion 632 for installing a jack 65 is provided on the floor fixing base 63, a jack contact portion 642 with which the piston portion 68 of the extended jack 65 contacts is provided on the structure fixing base 64, and the jack installation portion 632 is located below the jack contact portion 642. On the other hand, a jack installation portion for installing the jack 65 may be provided on the structure fixing base 64, a jack contact portion with which the piston portion 68 of the extended jack 65 contacts may be provided on the floor fixing base 63, and the jack installation portion may be located below the jack contact portion.

[0065] In the above-described embodiment, both the floor fixing portion 631 of the floor fixing base 63 and the structure fixing portion 641 of the structure fixing base 64 are steel frames. However, as shown in FIG. 12, the top of the piston portion 68 of the jack 65 and the beam (jack contact portion 642) may be fixed, and the structure fixing portion 641 may be a wire, a cable, or the like. The floor fixing portion 631 may also be a wire, a cable, or the like. In the lowering adjustment portion 62 shown in FIG. 12, as described above, the beam (jack contact portion 642) is fixed to the top of the piston portion 68 and supports its own weight. When the jack 65 contracts, the wire or cable bends, and the beam also descends together with the jack 65, so that an insulating state is achieved in which no force acts between the structure (foundation) and the floor. Also, as shown in FIG. 13, the structure fixing portion 641 may be a PC steel bar that penetrates the jack contact portion 642 and is joined to the jack contact portion 642 using a nut. The floor fixing portion 631 may be a PC steel bar that penetrates the jack installation portion 632 and is joined to the jack installation portion 632 using a nut 643. By using such wires, cables, or PC steel bars for the floor fixing portion 631 of the floor fixing base 63 and the structure fixing portion 641 of the structure fixing base 64, even when a horizontal relative displacement occurs between the floor portion 3 and the structure 2 due to horizontal seismic vibrations, the excitation force of the audience, or the like, it is possible to follow the displacement without resistance.

[0066] In the above-described embodiment, the floor portion 3 is installed in the recess 21 of the structure 2, and the side wall portion 23 of the structure 2 is provided on the side. However, it may be arranged on the structure 2, and the side wall portion 23 may not be provided on the side. In this case, a horizontal displacement restraint mechanism (not shown) is added in parallel with the support spring 4 so that the horizontal displacement of the floor portion 3 does not become excessive. Also, in the above-described embodiment, the jacks 65 and 51 are remotely operable electric jacks, but they may be manual jacks 65 and 51. Also, in the above-described embodiment, the lowering adjustment portion 62 is arranged in the vicinity of each of the plurality of support springs 4, but it is not necessarily arranged in the vicinity of each of the plurality of support springs 4. Also, the number of the lowering adjustment portion 62 and the support spring 4 may be set as appropriate.

[0067] The anti-vibration structure according to the present invention can be applied not only to a building facility having a newly installed anti-vibration floating floor, but also to an existing floating floor structure by adding the proposed mechanism to make it variable between a floating floor and a fixed floor.

[0068] In the above-described embodiment, the details of the jack 65 of the lowering adjustment portion 62 are described. However, a jack having the same configuration as the jack 65 of the lowering adjustment portion 62 may be adopted for the jack 51 of the lock mechanism 5 (raising adjustment portion 61).

Explanation of reference numerals

[0069] 1, 1B, 1C Anti-vibration structure 2 Structure 3 Floor portion 4 Support spring 5 Lock mechanism 6, 6B, 6C Floor height adjustment portion 7, 7B Screw jack 8 Hydraulic jack 61 Raising adjustment portion 62, 62B, 62C Lowering adjustment portion 63 Floor fixing base 64 Structure fixing base 65, 65B, 65C Jack 66 Sensor 67, 67B, 67C Cylinder section 68, 68B, 68C Piston section 71, 71B Worm wheel 76 Ball

Claims

1. A structure, a floor portion provided on the structure, a support spring that connects the structure and the floor portion and supports the floor portion so as to be displaceable in the vertical direction with respect to the structure, a lock mechanism arranged in parallel with the support spring and capable of switching between restraining and allowing vertical displacement of the floor portion with respect to the structure, and a floor height adjuster for adjusting the height of the floor portion with respect to the structure. The floor height adjuster has a lifting adjuster for lifting the floor portion, and a lowering adjuster for lowering the floor portion. The lowering adjuster has a floor fixing pedestal fixed to the floor portion, a structure fixing pedestal fixed to the structure and located above the floor fixing pedestal, and a jack arranged between the floor fixing pedestal and the structure fixing pedestal. The jack has a cylinder portion fixed to a first pedestal that is either the floor fixing pedestal or the structure fixing pedestal, and a piston portion inserted into the cylinder portion from the side of a second pedestal that is the other of the floor fixing pedestal and the structure fixing pedestal and displaceable in the vertical direction with respect to the cylinder portion. An end portion of the piston portion on the second pedestal side is arranged to face the second pedestal in the vertical direction, and when the piston portion is pulled out from the cylinder portion and the jack extends, it contacts the second pedestal for an anti-vibration structure.

2. The anti-vibration structure according to claim 1, wherein the jack is a remotely operable electric jack.

3. The lowering adjuster has a sensor capable of measuring the distance between the structure and the floor portion, and the driving of the jack stops when the distance between the structure and the floor portion measured by the sensor reaches a predetermined value. The anti-vibration structure according to claim 1 or 2.

4. The jack has a worm screw that rotates a worm wheel, and a screw shaft that moves up and down when the rotation of the worm screw is transmitted through the worm wheel. The screw shaft is a screw jack that becomes the piston portion, and the screw shaft is a trapezoidal screw. The anti-vibration structure according to any one of claims 1 to 3.

5. The jack has a worm screw that rotates a worm wheel, and a screw shaft that moves up and down when the rotation of the worm screw is transmitted through the worm wheel. The screw shaft is a screw jack that becomes the piston portion, and the screw shaft is a ball screw. The anti-vibration structure according to any one of claims 1 to 3.

6. The vibration isolation structure according to any one of claims 1 to 3, wherein the jack is a hydraulic jack.

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