KR20200049145A - Seismic device for distributing board using the seismic spring - Google Patents

Abstract

The present invention relates to a shock absorbing structure integrally formed with a plurality of springs independently reacting to vertical and horizontal vibration. According to the present invention, the shock absorbing structure integrally formed with a plurality of springs independently reacting to vertical and horizontal vibration comprises: a block (A) providing an installation space for a switchboard; a lower frame (100); an upper fixing plate (200); a lower fixing plate (300); an auxiliary frame (400); and a shock absorbing unit (500), wherein the shock absorbing unit (500) includes a main spring (510), an upper plate (520), a lower plate (530), and an auxiliary spring (540). According to the present invention, various types of vibration can be perfectly blocked.

Description

A buffer structure in which a plurality of springs that respond to vertical and horizontal vibrations are integrally constructed {Seismic device for distributing board using the seismic spring}

The present invention relates to a shock absorbing structure that blocks vibration from being transmitted to the switchboard by exerting a buffer function when the crust changes due to earthquake or the like while enabling accurate horizontal installation of the switchboard on the ground with irregularities, and more specifically, the switchboard and the ground The main spring installed vertically in the liver suppresses the vibration generated in the vertical direction, and the auxiliary spring installed in the periphery of the main spring suppresses the vibration generated in the horizontal direction, and as a result, actively blocks vibrations generated from all directions. Of course, as it is provided in a form that can be installed on the side, including the top surface of the concrete block for installation of the switchboard, a plurality of springs that respond to vertical and horizontal vibrations that can be easily installed at various locations without being limited to a location are integrated. It relates to a buffer structure.

In general, the switchboard is a device that collects power produced by power plants and substations, operates or controls it, or puts and manages switches, instruments, and relays (relays) regularly for the operation of electric motors.

As above, the switchboard is shock-proof so that dangerous parts can be safely maintained without being damaged or deformed by external shocks such as natural disasters because various dangerous parts that flow high-voltage currents are closely installed in the interior space. The development of the switchboard having a has been ongoing.

For example, as an example of a switchboard having an earthquake-resistance property, there is published "Patent-proof seismic device for water distribution boards using a seismic spring" as an example of the switchboard. It is inserted into the inner space of the housing, and a fixed plate is provided to support the ground, and as the spring is interposed between the housing and the fixed plate, the spring exerts a cushioning effect between the fixed plate and the housing to shake the ground due to earthquakes. It is a mitigating technique.

As another example, Patent Publication No. 10-1768031 "Seismic Unit for Water Distribution Using a Plate Spring" is published, and the related art has a cylindrical shape that is vertically insulated to be inserted into an outer periphery of a vertically placed plate spring and a plate spring. It is made of an elastic body of, and is composed of fastening bolts arranged through the plate spring so that the switchboard can be interlocked with the ground through the seismic unit.

The seismic unit of the prior art made of the above configuration suppresses the vertical vibration generated by the external environmental factors of the plate spring vertically placed between the ground and the switchboard, and the elastic body installed as if surrounding the outer periphery of the plate spring is an external environmental factor. It serves to suppress the horizontal vibration caused by.

As the above-mentioned prior art, various elastic members such as springs are used as a method for imparting earthquake resistance to the switchboard, and in practice, the elastic members actively block the transmission of various types of vibrations caused by earthquakes to the switchboard. have.

However, all switchboard buffer units, including the two prior arts exemplified above, are installed on the upper surface of the ground or buried by recessing part of the ground. It was difficult to do. Accordingly, concrete blocks for distribution panel installation have been provided to easily level the switchboard by pouring concrete on the ground, but secondary problems such as deformation or destruction between the ground and blocks occurred due to earthquake.

Therefore, as the coupling between the concrete block for installation of the switchboard and the ground is firmly established, there is an urgent need for a buffer structure capable of easily installing the switchboard without regard to the plane, side, and depression of the concrete block for installation of the switchboard.

Published Patent Publication No. 10-2011-0036874 "Seismic device for switchgear using seismic spring" Registered Patent Publication No. 10-1768031 "Seismic unit for water distribution in and out using plate spring"

The present invention was created to more actively solve the above problems, and provides a shock absorbing structure that can actively prevent vibrations generated from multiple angles, such as vertical or horizontal, from being transmitted to the switchboard when the crust changes such as an earthquake. What you want to do is the main solution.

In addition, the present invention is provided to enable horizontal installation on the ground with a lot of irregularities or bends, as well as the flat section, depression section, edge, etc. of the concrete block for the switchboard constructed on the ground regardless of the position, and the same at various positions. Another solution is to provide an installable function.

In order to achieve the above-mentioned problem, the structure of the buffer structure in which a plurality of springs respectively responding to vertical and horizontal vibrations proposed in the present invention are integrally configured is as follows.

The buffer structure of the present invention is a block (A) that provides the installation space of the switchboard by pouring concrete on the ground; And, the lower frame (100) is fixedly arranged on the block (A) to induce the seating of the switchboard; and, Block (A) the upper fixing plate 200 extending from the side of the lower frame 100 to the outer region of the block in close contact with the upper surface; And, the lower fixing plate 300 is bent vertically fixed to the side of the block and the ground; And, the auxiliary frame 400 is projected from the vertical surface of the lower fixing plate 300 to the outer region of the block (A), which is arranged to have the same vertical line as the upper fixing plate 200; And, and the upper fixing plate 200 It characterized in that it is composed of; buffer unit 500 is installed in a space spaced between the auxiliary frame 400.

In particular, the upper buffer unit 500 is a main spring 510 that is vertically placed vertically; And, disposed at the top and bottom of the main spring 510, each end of the main spring by the depression 521 formed in the center A combined top plate 520; And lower plate 530; And, the upper plate 520 and the lower plate 530 includes one or more pair of protrusions 522 that protrude in the same vertical line along the periphery of each depression 521, , Both ends are made of a ring, and the auxiliary spring 540 is installed for each of the protrusions 522 of the upper and lower plates.

In addition, the above main spring 510 uses a compression spring having a wide pitch interval, and the above auxiliary spring 540 uses a tension spring with a close pitch interval, but the above main spring 510 and an auxiliary spring 540 are used. It is characterized by being composed of different elastic strength.

In addition, the upper top fixing plate 200 is characterized in that by stacking the rubber plate (B) on the contact surface with the block (A) to prevent the vibration generated in the ground is transmitted to the switchboard through the top fixing plate.

In addition, the upper upper fixing plate 200 is provided with a friction member (C) in which several friction beads are inserted in a constant arrangement on the contact surface with the block (A), the friction member of the shock absorbing unit 500 by vibration It is characterized in that the binding force of the bolt and nut coupled between the buffer structure 1 and the switchboard is prevented from being lost by inducing the minimum slide movement in response to the movement.

According to the present invention made of the configuration as described above, the main spring made of a compression spring with a relatively wide pitch interval and the auxiliary spring made of a tension spring with a close pitch interval are installed on the upper and lower plates, respectively. The tension and shrinkage forces occur between the lower plates at the same time, so that the separation space does not expand or contract, and a constant gap is maintained at all times, and the main spring and auxiliary spring are composed of elastic forces that are applied to each other, and they respond immediately to a variety of progress and deliver them to the switchboard. It has the effect of completely blocking various vibrations.

In addition, the present invention is coupled to the recessed portions formed on the upper and lower plates, respectively, and the main springs vertically installed impart elasticity in the vertical direction within the separation space between the upper and lower plates, and in addition, the protruding portions projecting downward along the periphery of the depressions. By providing elastic force in the horizontal direction by a plurality of auxiliary springs that are fastened by ring fittings, the vertical vibrations are mitigated by the reaction of the main spring, and the horizontal vibrations are mitigated by the reaction of the auxiliary springs. As the main spring and the auxiliary spring react simultaneously and mitigate, it is expected to have the advantage of effectively blocking vibrations generated at various angles.

In addition, the present invention can be installed to be maintained horizontally regardless of uneven or curved ground based on the elastic force possessed by the shock absorbing unit, in particular, the shock absorbing unit of the present invention, as well as the flat and recessed areas of the concrete block for installing the switchboard, There is another effect that the limited range of the installation site is expanded because it can be easily installed in the side section of the block that could not be installed before.

1 is a perspective view of a buffer structure and a switchboard in which a main spring and an auxiliary spring, each of which responds to vertical and horizontal vibrations constructed according to a preferred embodiment of the present invention, are integrally formed.
Figure 2 is an exploded perspective view of Figure 1;
Figure 3 is a side view of Figure 1;
Figure 4 is a perspective view of a buffer unit configured according to a preferred embodiment of the present invention.
Figure 5 is an exploded perspective view of Figure 4;
Figure 6 is a perspective view of a buffer structure consisting of a main spring and an auxiliary spring, each of which responds to vertical and horizontal vibrations constructed according to another embodiment of the present invention.
Fig. 7 is a side view of Fig. 6;
Fig. 8 is a state diagram of use of Fig. 6;

Hereinafter, with reference to the accompanying drawings, the configuration of the present invention and the effects and effects thereof will be collectively described.

Advantages and features of the present invention, and methods for achieving them will be clarified with reference to embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and may be implemented in various different forms, and only the present embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention pertains. It is provided to completely inform the person having the scope of the invention, and the present invention is only defined by the scope of the claims. And throughout the specification, the same reference numerals refer to the same components.

The present invention relates to a shock absorbing structure that blocks the transmission of vibrations to the switchboard by exerting a cushioning function when the crust changes due to earthquake or the like while enabling accurate horizontal installation of the switchboard on the ground with irregularities.

Above all, the main spring installed vertically between the switchboard and the ground suppresses the vibration generated in the vertical direction, and the auxiliary spring installed one or more around the main spring suppresses the vibration generated in the horizontal direction, resulting in everywhere. As well as actively blocking the vibrations, the installation of a concrete block for installation of the switchboard and the installation of a side surface, as well as side mounting, are not limited to the place, and can be easily installed in various locations, and each responds to vertical and horizontal vibrations. Note that the spring is related to the integrally configured buffer structure.

1 is a perspective view of a shock absorbing structure in which a plurality of springs respectively responding to vertical and horizontal vibrations are integrally constructed according to a preferred embodiment of the present invention, FIG. 2 is an exploded perspective view of FIG. 1, and FIG. 3 is a side view of FIG. 1 to be.

1, the switchboard of the present invention is placed on the top of the concrete block (A) for installation of the switchboard, where flatness is secured by pouring concrete on the ground, the lower frame 100 to induce the seating of the switchboard; and, the lower frame (100) the top fixing plate 200 extending from the side to the outer region of the block; and, the bottom fixing plate 300 is bent vertically and fixedly adhered to the ground and the side of the block; and, the block from the vertical side of the bottom fixing plate 300 (A) is installed to protrude to the outer region, the auxiliary frame 400 is disposed to have the same vertical line as the upper fixing plate 200; And, the upper fixing plate 200 and the auxiliary frame 400 is installed in spaced apart space It is composed of; a buffer unit 500.

The above concrete block (A) is to build a solid and flat ground by pouring concrete on the ground. In general, horizontal installation is difficult when installing a switchboard directly on uneven and curved ground. Various problems such as erosion of the ground may occur due to wind and rain, leaving the initial installation location or tilting the switchboard. Accordingly, it is possible to place the switchboard flat and firmly for a long time by pouring concrete to secure the life of the ground.

For example, the upper block (A) can be constructed somewhat higher on the ground to prevent rainwater accumulated in the ground from entering the switchboard during rainy season.

The upper lower frame 100 is fixedly arranged on the upper surface of the block (A) and serves to induce the seating of the switchboard. In the present invention, a 'c' shaped steel was used, but in a square frame according to the shape and installation conditions of the switchboard. It can be made, it is preferable to configure the switchboard in a form that can be securely seated and fixed.

For example, in the present invention, the lower frame 100 is not separately restrained on the block A, but it is natural that the installation position can be fixed by an anchor bolt according to the shape of the switchboard or installation conditions.

The upper upper fixing plate 200 serves to interconnect the lower frame 100 and the buffer unit 500 of the present invention. According to the present invention, the upper fixing plate 200 has a shape that is bent 'b', the vertical surface is coupled to the side of the lower frame 100 by bolts, and the horizontal surface is in a state in close contact with the upper surface of the block (A) It is arranged to extend to the outer side of the side.

As above, the upper end of the buffer unit 500 is assembled by bolts on the bottom surface of the upper fixing plate 200 which extends beyond the side of the block A to the outer region.

The upper and lower fixing plates 300 connect the ground and the block A to each other to induce a more robust coupling between the ground and the block. The lower fixing plate 300 for actively performing this has a 'b' shaped bent shape, and the horizontal surface is fixedly fixed to the ground by an anchor bolt, and the vertical surface is fixedly fixed to the side surface of the block A by the anchor bolt.

The upper auxiliary frame 400 is disposed at a predetermined distance from the lower side of the upper fixing plate 200 to be assembled with the lower end of the buffer unit 500 and bolts.

The upper auxiliary frame 400 is installed to face the outer side of the block on the vertical surface of the lower fixing plate 300 in order to be positioned below the upper fixing plate 200, the end of the auxiliary frame is exposed outside of the upper fixing plate 200 It is arranged on the same vertical line as the area.

In the case of an earthquake, the switchboard installed as above generates vibrations on the ground and blocks for the first time, and the vibrations generated from the ground are received by the lower fixing plate 300 and transmitted to the auxiliary frame 400, and the auxiliary frame receiving vibration from the lower fixing plate is Transfer to the buffer unit 500 to suppress vibration.

As another example, the vibration occurring at the same time as the ground and the block is transmitted from the lower fixing plate 300 to the auxiliary frame 400, and the auxiliary frame received from the lower fixing plate is transmitted to the buffer unit 500 to suppress vibration, The upper fixing plate 200 is directly delivered to the buffer unit 500.

On the other hand, the upper upper fixing plate 200 of the present invention blocks itself by preventing vibrations generated from the ground from being transmitted to the switchboard through the upper fixing plate by stacking a separate rubber plate B on the contact surface with the block A.

4 is a perspective view of a buffer unit constructed according to a preferred embodiment of the present invention, and FIG. 5 is an exploded perspective view of FIG. 4.

As shown in Figure 4, the buffer unit 500 of the present invention is a main spring 510 vertically inserted; And, the upper plate 520 coupled to the top of the main spring; And, the lower plate coupled to the bottom of the main spring (530); And, at least one auxiliary spring 540 is installed along the periphery of the main spring; consists of.

The above main spring 510 can use any material that has its own cushioning properties, such as coil material, cylindrical rubber, or silicone material, for the purpose of suppressing vertical and vertical vibration among vibrations occurring at various angles from an earthquake. The invention uses coil spring, which is the most excellent material for buffering.

In particular, the main spring 510 of the present invention generally uses a compression spring that is excellent in compression and relaxation because the pitch interval is somewhat widened to correspond to the characteristics of the earthquake that expands after contraction.

The upper plate 520 is formed of a circular or polygonal plate material and is disposed on the upper side of the main spring 510, and further provided with a depression 521 having a diameter corresponding to the outer diameter of the main spring on the center side of the bottom surface of the upper plate 520. To fix the top of the main spring.

The upper lower plate 530 is made of a circular or polygonal plate material like the upper plate 520 and is disposed under the main spring 510. In addition, a depression having a diameter corresponding to the outer diameter of the main spring 510 is further provided at the center of the upper surface of the lower plate 530 to fix the bottom of the main spring.

For example, the recessed portion 521 formed on the bottom surface of the upper plate 520 and the recessed portion formed on the upper surface of the lower plate 530 are disposed in the same vertical line with each other, so that it is natural that the correct standing position of the main spring 510 is determined. In addition, the separation distance between the upper and lower plates is determined by the elastic force of the main spring and the main spring. In addition, by setting the length and elastic strength of the main spring 510 differently, it is possible to adjust the separation distance between the upper and lower plates and expand or reduce the buffering range according to various intensities.

 As above, the upper plate 520 disposed on the upper side of the main spring 510 receives vibrations generated from the upper layer of the ground, presses the main spring from the upper side to the lower side, and the lower plate 530 disposed on the lower side of the main spring is the lower layer of the ground. By receiving the vibration generated from the pressure, the main spring is pressed from the lower side to the upper side, thereby causing the main spring to generate elasticity to induce the buffer force to be expressed.

On the other hand, the upper upper plate 520 includes one or more protrusions 522 that protrude downward along the outer periphery of the recessed portion at a distance from the recessed portion 521, and the upper lower plate 530 also includes the outer peripheral edge of the recessed portion. Accordingly, it is formed to protrude upward and further includes a protrusion arranged on the same vertical line as the protrusion of the top plate.

The above auxiliary spring 540 is a coil material, a cylindrical rubber or silicone material, etc. for the purpose of suppressing horizontal and horizontal vibration among vibrations generated at various angles from an earthquake. Although it can be used, the present invention uses a coil spring that returns to its original shape immediately when the external force is extinguished when it is easily bent even with a small external force while having the best buffering property.

In particular, in the auxiliary spring 540 of the present invention, the main spring 510, the upper plate 520, and the lower plate 530, which are slightly deviated from the initial installation position by the shaking vibration alternately left and right in the event of an earthquake, return to the original position. It is desirable to use a tension spring that is excellent in expansion and contraction because the pitch interval is closely formed so as to be able to return.

In addition, the upper spring 540 may be easily assembled by hooking each of the protrusions 522 of the upper plate 520 and the protrusions of the lower plate 530 by having both ends formed in hooks. In addition, as the upper and lower plates are fastened in a ring manner, natural rotation between the upper plate and the lower plate and the auxiliary spring is achieved, thereby inducing an immediate response to horizontal vibration.

FIG. 6 is an exploded perspective view of another embodiment of the present invention in which a friction member C slideable in a multi-way slide is installed between the top fixing plate 200 and the block A, and FIG. 7 is a side view of FIG. 6 , FIG. 8 is a use state diagram of FIG. 6.

As shown in Fig. 6, the cushioning structure 1 of the present invention is further provided with a friction member (C) in which a plurality of friction beads are arranged in a regular pattern between the upper fixing plate 200 and the block (A), and the upper friction In order to prevent deviation of the frictional beads of the member C and to guide accurate slide movement, the bottom surface of the upper fixing plate 200 includes a depression region 210 corresponding to the movement path of the frictional beads.

As described above, the friction member (C) installed between the upper fixing plate 200 and the block (A) provides a movable upper portion of the upper fixing plate by a friction bead, and corresponds to the shock absorbing unit 500 that is shaken by vibration. The upper fixing plate 200 may perform minimal movement.

For example, when a severe movement occurs in the buffer unit 500 due to vibration while the lower frame 100 is firmly fixed to the block (A), minute movements of the buffer unit 500 and the lower frame through the lower frame There is a problem in that the binding force is lost by being transmitted to the bolts and nuts that bind the blocks.

Accordingly, according to the present invention, by installing a friction member (C) capable of sliding movement in multiple directions between the lower frame (100) and the block (A), the upper part is moved according to the movement of the shock absorbing unit (500) at a level that does not force the switchboard. By inducing minimal movement of the fixing plate 200 and the lower frame 100, the micro vibration transmitted to the bolt and the nut was reduced.

As described above, the buffer unit 500 of the present invention is coupled to the recesses 521 formed in the upper plate 520 and the lower plate 530, respectively, so that the main spring 510 is vertically installed within the separation space between the upper plate and the lower plate. By imparting elastic force in the vertical direction, and a plurality of auxiliary springs 540 fastened by ring fitting to the projecting portion 522 protruding downward along the periphery of the depression, the elastic force in the horizontal direction is provided, so that the vertical vibration The main spring reacts to alleviate the vibrations, and the horizontal vibrations are alleviated by the auxiliary springs, and the diagonal vibrations effectively mitigate the vibrations occurring at various angles as the main springs and the auxiliary springs react simultaneously to alleviate the vibrations. Of course, the main spring composed of a compression spring with a relatively wide pitch gap and the auxiliary spring composed of a tension spring with a close pitch gap Tensile force and contraction force occur simultaneously between the upper plate and the lower plate, so that the separation distance between the upper plate and the lower plate does not expand or contract, and a constant gap is maintained at all times.

According to the shock absorbing unit 500 and the shock absorbing structure using the main spring 510 and the auxiliary spring 540 integrally responding to the vertical and horizontal vibrations made of the above-described configuration, the pitch spring is somewhat wider than the compression spring. The main spring is made of, and the auxiliary spring made of a tensile spring with close pitch spacing is installed on the upper and lower plates, respectively. From this, tensile and contractive forces occur between the upper and lower plates 520 and 530 at the same time, thereby expanding the separation space. It is not reduced or reduced, and a constant gap is maintained at all times, and the main spring and the auxiliary spring are composed of elastic force applied to each other, so that they can respond to various intensities immediately and completely block various vibrations transmitted to the switchboard.

In addition, the main spring, which is vertically installed by being coupled to the recessed portions 521 formed in the upper plate 520 and the lower plate 530, provides elastic force in the vertical direction within the separation space between the upper plate and the lower plate, along with the surroundings of the recessed portion. Accordingly, a plurality of auxiliary springs 540 that are fastened by hooking the protrusions 522 protruding downward impart elastic force in the horizontal direction, so that the vibration caused by the vertical is relieved by the reaction of the main spring 510, and the horizontal The vibration of the auxiliary spring is alleviated by the reaction, and the vibration caused by the diagonal can be effectively blocked by the vibration occurring at various angles as the main spring and the auxiliary spring react and alleviate.

Lastly, the buffer unit 500 can be installed to be maintained horizontally regardless of uneven or curved ground based on the elastic force possessed by the buffer unit 500. In particular, the buffer unit of the present invention has a flat surface and a recessed area of the concrete block (A) for distribution panel installation. Of course, it is possible to install easily on the side section of the block that could not be installed before, thereby extending the limited scope of the installation site.

The present invention described above has been described with reference to one embodiment shown in the drawings, but this is only an example, and various modifications and equivalent other embodiments are possible from those skilled in the art. Should be clarified. Therefore, the true technical protection scope of the present invention should be interpreted by the appended claims, and all technical spirits within the equivalent scope should be interpreted as being included in the scope of the present invention.

A. Block B. Rubber plate
100. Lower frame 200. Upper fixing plate
300. Bottom fixing plate 400. Auxiliary frame
500. Shock absorbing unit 510. Main spring
520. Top plate 530. Bottom plate
540. Second Spring

Claims (5)

Block (A) that provides the installation space of the switchboard by pouring concrete on the ground;
Block (A) is arranged on the upper surface of the lower frame 100 to induce the seating of the switchboard;
Block (A) the upper fixing plate 200 extending from the side of the lower frame 100 to the outer region of the block in close contact with the upper surface;
A lower fixing plate 300 that is vertically bent and fixed to the side of the block and the ground;
An auxiliary frame 400 protruding from the vertical surface of the lower fixing plate 300 to the outer region of the block A, and disposed to have the same vertical line as the upper fixing plate 200;
A buffer unit 500 installed in a space spaced between the upper fixing plate 200 and the auxiliary frame 400;
A shock absorbing structure comprising a plurality of springs, each of which reacts to vertical and horizontal vibrations, characterized in that it consists of.
According to claim 1,
The buffer unit 500 is the main spring 510 is vertically arranged to be placed;
A top plate 520 disposed at the top and bottom of the main spring 510 and coupled to each end of the main spring by a depression 521 formed at the center; And a lower plate 530;
The upper top plate 520 and the lower plate 530 include one or more pair of protrusions 522 that protrude in the same vertical line along the periphery of each depression 521, and both ends are formed of rings to form a top plate and An auxiliary spring 540 installed for each protrusion 522 of the lower plate;
A shock absorbing structure comprising a plurality of springs, each of which reacts to vertical and horizontal vibrations, characterized in that it consists of.
According to claim 2,
The upper spring 510 uses a compression spring with a wide pitch gap,
The auxiliary spring 540 uses a tension spring with close pitch spacing,
The upper spring 510 and the auxiliary spring 540 is a shock absorbing structure composed of a plurality of springs, each of which responds to vertical and horizontal vibrations, which is composed of different elastic strengths.
According to claim 1,
The upper upper fixing plate 200 stacks a rubber plate (B) on the contact surface with the block (A) to prevent vibrations generated from the ground from being transmitted to the switchboard through the upper fixing plate, respectively. A buffer structure in which a plurality of responsive springs are integrally formed.
According to claim 1,
The upper upper fixing plate 200 is provided with a friction member (C) in which several friction beads are inserted in a constant arrangement on the contact surface with the block (A),
The upper friction member (C) is vertical to block the loss of the binding force of the bolt and nut coupled between the buffer structure (1) and the switchboard as it induces the minimum slide movement in response to the movement of the shock absorbing unit (500) due to vibration. And a buffer structure in which a plurality of springs each responding to horizontal vibration are integrally formed.

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