JP2014126073A - Seismic base isolation pallet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect an item to be seismic base isolated in high seismic base isolation characteristic with less-expensive configuration against vibration accompanied by motion of a movable body.SOLUTION: A seismic base isolation pallet 120 mounted at an optional movable body to support an item to be seismic base isolated from below in a vertical direction comprises a lower frame 150 forming a rigid body positioned at a mounted side of the movable body extending in a horizontal direction; an upper frame 152 forming a rigid body positioned at the item to be seismic base isolated and extending in the horizontal direction, coil springs 154 of which one end is fixed to the lower frame and the other end is fixed to the upper frame so as to accumulate kinetic energy received by one frame as elastic energy; oil dampers 156 of which one end is fixed to the lower frame and the other end is fixed to the upper frame so as to attenuate kinetic energy received by one frame and transmit it to the other frame. Cut-off frequency got by the seismic base isolation palette is set to a value between spring lower resonance frequency and spring upper resonance frequency of the movable body.

Description

  The present invention relates to a vibration isolation pallet that protects a vibration isolation object from vibration associated with movement of a moving body.

  In order to carry out uniform and easy cargo handling work on moving bodies such as trucks and to efficiently arrange and store them in warehouses, etc. A pallet (pedestal) is placed to support the load.

  Once a load is loaded on the pallet, the load and the pallet are handled in an integrated manner not only during the handling operation but also when the moving body is moved or stored. Therefore, the pallet can be used not only as a pedestal but also as a vibration isolator that protects the load from vibrations caused by movement of the moving body.

  Moreover, in order to restrict the relative movement between the upper part and the lower part of the pallet when transporting the cargo and the pallet, a technique for locking the upper part and the lower part of the pallet with a lock device is also disclosed (for example, Patent Document 1). . Furthermore, a technique is also disclosed in which a spring element and a damping element are provided in series with respect to the rotational inertia added mass to reduce the resonance frequency (longer period) and reduce the response to a high frequency input (for example, Patent Document 2).

Japanese Patent No. 3777698 Japanese Patent No. 4347273

  By using the above-described technology, it is possible to protect the vibration-isolated object from vibration during cargo handling work or transporting the vibration-isolated object, and to avoid great damage to the vibration-isolated object. However, in recent years, even if the function of the oscillated object itself is not impaired, when the oscillated object is sold as a product, the packaging of the oscillated object and the fine rubs on the oscillated object itself can be damaged. The number of consumers concerned increased, and the product value could be reduced due to minor damage. For example, when a plurality of vertically formed bottles are vertically arranged and transported in the horizontal direction, the bottles may be rubbed and damaged, or buckling may occur depending on how the bottles are arranged. there were.

  In addition, in order to avoid damage to the product, the product may be housed and transported in a carton. However, in recent years, the sales opportunity for displaying a carton used for the purpose of protecting the product together with the product at the time of sale of the product has increased. However, it has become necessary to protect the exterior.

  It is possible to apply a curing material for each product or carton so as to avoid the above-described minor damage, but there is a problem that complicated packing work is forced and the transportation cost increases.

  In view of such problems, the present invention is to provide an isolation pallet that can protect a vibration-isolated object with higher vibration isolation from vibration associated with movement of a moving body with an inexpensive configuration. It is aimed.

  In order to solve the above-mentioned problem, the vibration-isolating pallet of the present invention, which is installed on an arbitrary moving body and supports the vibration-isolated object from below vertically, is positioned on the installation side of the moving body and extended in the horizontal direction. A lower frame that forms a rigid body, an upper frame that forms a rigid body that is located on the side of the vibration-isolated object and extends in the horizontal direction, one end fixed to the lower frame, the other end fixed to the upper frame, and one frame received An elastic member that stores kinetic energy as elastic energy, and a damper that has one end fixed to the lower frame and the other end fixed to the upper frame, and that attenuates the kinetic energy received by one frame and transmits it to the other frame. The cutoff frequency by the vibration isolation pallet is set to a value between the unsprung resonance frequency and the sprung resonance frequency of the moving body.

  A horizontal link that restricts the relative movement in the horizontal direction while allowing the relative movement in the vertical direction between the lower frame and the upper frame may be further provided.

  A first stopper piece, which is fixed to one of the lower frame and the upper frame and which is provided with a bar extending in the vertical direction and provided with two restricting portions protruding in the horizontal direction, and the other of the lower frame and the upper frame And a stopper having a second stopper piece that is movable between the two restricting portions by inserting the rod into the through hole in the vertical direction.

  The restriction part may be formed so that the position in the longitudinal direction of the rod body can be changed.

  The upper frame may support a plurality of separable objects to be separated at different horizontal positions.

  According to the present invention, with a low-cost configuration, it is possible to protect the vibration-isolated object with higher vibration isolation from vibration associated with the movement of the moving body, and to suppress a reduction in the commercial value of the vibration-isolated object. Become.

It is explanatory drawing for demonstrating the cargo handling work of a to-be-vibrated object. It is a perspective view for demonstrating the schematic structure of a vibration isolation pallet. It is explanatory drawing for demonstrating a horizontal link. It is explanatory drawing for demonstrating a stopper. It is explanatory drawing which compared the spectral response of the to-be-isolated object with respect to the vibration before employ | adopting a vibration isolating pallet and after employ | adopting. It is explanatory drawing which compared the time response of the to-be-isolated object with respect to the vibration before employ | adopting a vibration isolating pallet and after employ | adopting.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

(Transport system 100)
FIG. 1 is an explanatory diagram for explaining the cargo handling work of the vibration-isolated object 110. Although various things can be targeted as the object to be oscillated 110, here, a plurality of vertically long bottles are arranged in a horizontal direction in a vertically standing state, and a plurality of bottles arranged in such a manner are arranged. Are assumed to be packaged in a plurality of layers (bulk packaging) via cardboard, cartons or the like.

  In the present embodiment, four separable objects 110 that can be separated are loaded on one seismic isolation pallet 120. Then, if necessary, the four oscillating objects 110 are covered from the outside of the four oscillating objects 110 with a film that prevents damage to the oscillating object 110 and fastened with a string. Finally, the vibration isolation pallet 120 is lifted together with the vibration isolation object 110 and loaded on a truck 130 as a moving body. The vibration isolation pallet 120 is installed on the loading platform by fastening it with fastening members such as bolts, for example, so as to avoid horizontal displacement of the truck 130 with respect to the loading platform as much as possible.

  The vibration-isolating pallet 120 has a horizontal dimension of, for example, 2300 mm × 2300 mm. For example, one to four vibration-isolating pallets 120 can be provided on the loading platform of the truck 130 having a horizontal dimension of 9600 mm × 2300 mm. Here, the size of the vibration isolation pallet 120 is adjusted to the bottom area of the vibration isolation material 110, but the size is not limited to this and can be formed in any size. In the present embodiment, an object is to suppress vibrations in the vertical vertical direction generated in the vibration-isolated object 110 through the vibration isolation pallet 120, particularly as the truck 130 moves (runs).

  The truck 130 is equipped with an air suspension (not shown) that is an elastic body using the elasticity of air. The air suspension can arbitrarily set a spring constant by changing the volume of air contained therein, and can realize extremely soft elasticity. Originally, it is desirable to attenuate the resonance frequencies such as the sprung resonance frequency (1 to 1.5 Hz) generated in the track 130 and the unsprung resonance frequency (10 to 15 Hz) by the air suspension. However, since there are many restrictions on the provision of a damping mechanism for damping the unsprung resonance in the track 130 itself, and the design is difficult, the air suspension normally attenuates only the vibration of the sprung resonance effectively. . Therefore, vibrations near the unsprung resonance frequency often remain.

  The object to be shaken 110 such as the bottle is subjected to vibration in the vicinity of the unsprung resonance frequency accompanying the movement of the track 130 at the time of transportation, for example, and the label attached to the bottle or a fine scratch on the bottle itself. May occur. Such fine scratches do not impair the function of the object to be oscillated 110, for example, the function of containing and holding the liquid in a sealed state. Improving tremor is urgently needed. An object of the present embodiment is to protect the vibration-isolated object 110 from vibrations caused by movement of the track 130 with higher vibration isolation properties with an inexpensive configuration. Hereinafter, a schematic configuration of the vibration isolation pallet 120 that realizes such an object will be described.

(Seismic isolation pallet 120)
FIG. 2 is a perspective view for explaining a schematic configuration of the vibration isolation pallet 120. The vibration isolation pallet 120 includes a lower frame 150, an upper frame 152, a coil spring (elastic member) 154, an oil damper (damper) 156, a horizontal link 158, and a stopper 160. Here, as shown in FIG. 2, two directions orthogonal to each other on the horizontal plane are defined as an x direction and a y direction, and a vertical direction is defined as a z direction.

  The lower frame 150 is located on the installation side (the loading platform side of the truck 130), is made of metal, and forms a rigid body that extends in the horizontal direction. The upper frame 152 is located on the side of the object to be shaken 110, is made of metal, and forms a rigid body that extends in the horizontal direction corresponding to the lower frame 150. The vibration isolator 110 is disposed above the upper frame 152 and supported by the upper frame 152.

  As can be understood with reference to FIG. 1, the vibration-isolated object 110 can be stacked in any number of stages, so that the height is an allowable height of the loading platform of the truck 130, for example, an arbitrary number of stages within 2400 mm. Of height. Then, the separable object 110 that can be separated has a horizontal dimension of 1150 mm × 1150 mm, its height is close to 2400 mm, and the ratio of the bottom area to the height is biased. In such a dimension relationship that is long in the vertical direction, the rigidity in the vertical direction of the vibration isolator 110 is increased, but the rigidity in the horizontal direction is weakened. Therefore, in the present embodiment, as described above, four separable objects 110 that can be separated are stacked on the upper frame 152 of one vibration isolating pallet 120 at different positions in the horizontal direction, and the periphery is film. Surround with etc.

  In this way, by expanding the bottom surface and increasing the ratio of the bottom area to the height, the external dimensions of the four driven objects 110 appear to be, for example, 2300 mm × 2300 mm × 2400 mm, and the ratio of the bottom area to the height This improves the balance and increases the rigidity in both the vertical and horizontal directions. In addition, since the four oscillating objects 110 are restrained and supported by one upper frame 152, the oscillating object 110 can be regarded as one rigid body through the upper frame 152 when observed from the track 130 side. it can. In this embodiment, since vibration associated with the movement of the track 130 is targeted for vibration isolation, it is only necessary to suppress vibration from the track 130 side, and vibrations can be generated even if the entire four vibration-isolated objects 110 are not completely restrained. A high effect can be obtained even by restraining the vibration-isolated object 110 in the upper frame 152 to which is transmitted. In this way, the overall distortion of the vibration-isolated object 110 is reduced, and the vibration isolation performance can be enhanced even with respect to horizontal vibration.

  Further, by widening the bottom surface, the separation distance between the opposing coil springs 154 and oil dampers 156 can be increased in the vibration isolation pallet 120, and the rotational motion of the four vibration-isolated objects 110 generated in parallel with the horizontal motion. It is possible to improve the stability against (rocking motion).

  However, the number of the vibration-isolated objects 110 loaded on the upper frame 152 is not limited to four, and as long as there are a plurality of the vibration-isolated objects 110, the ratio of the bottom area to the height is increased, and the plurality of vibration-isolated objects 110 through the upper frame 152 are increased. Can be handled in an integrated manner, and the vibration isolation can be improved.

  For example, the coil springs 154 are arranged at four corners of the upper frame 152 and the lower frame 150 and at the center of the corners, and are provided at a total of nine places as shown in FIG. The coil spring 154 has one end fixed to the lower frame 150 and the other end fixed to the upper frame 152, and functions as an elastic member that accumulates kinetic energy received by one frame (here, the lower frame 150) as elastic energy. .

  Two oil dampers 156 are arranged opposite each other on two opposing sides (here, sides extending in the x direction) corresponding to the outermost sides of the upper frame 152 and the lower frame 150. Therefore, the oil dampers 156 are provided at a total of four locations. Further, the two oil dampers 156 on one side are provided symmetrically with respect to the center of the side as a target point. The oil damper 156 has one end fixed to the lower frame 150 and the other end fixed to the upper frame 152, and attenuates the kinetic energy received by one frame (here, the lower frame 150) to reduce the other frame (here, the upper frame 150). It functions as an attenuator that suppresses resonance to the frame 152).

  Two horizontal links 158 are arranged opposite to each other on the outermost sides of the upper frame 152 and the lower frame 150, and are provided at a total of eight locations. The horizontal link 158 has one end fixed to the lower frame 150 and the other end fixed to the upper frame 152. The horizontal link 158 allows the relative movement of the lower frame 150 and the upper frame 152 in the vertical direction (z direction) while allowing the horizontal direction ( The relative movement in the x and y directions) is constrained, the rotational motion (rocking motion) with respect to the four vibration-isolated objects 110 is constrained, and the collapse of the vibration-isolated object 110 is prevented.

  FIG. 3 is an explanatory diagram for explaining the horizontal link 158. In the horizontal link 158, two restriction members 158a intersect, one end of one restriction member 158a is rotatably fixed to a fixing member 158b protruding from the upper frame 152, and the other end is slid on the lower frame 150. It is engaged with the mechanism 158c so as to be slidable in the horizontal direction. The other restricting member 158a is arranged symmetrically with the one restricting member 158a, and one end is rotatably fixed to a fixing member 158d facing the fixing member 158b of the lower frame 150, and the other end is The upper frame 152 is engaged with the sliding mechanism 158e so as to be slidable in the horizontal direction. The two limiting members 158a are engaged with each other at the center position 158f.

  With the above configuration, for example, when the lower frame 150 and the upper frame 152 act so as to be separated in the vertical direction as shown in FIG. 3A, the two limiting members 158a are fixedly rotated with the fixing members 158b and 158d. With the position as a fulcrum, the other end slides on the sliding mechanisms 158c and 158e, and the vertical angle α formed by the two restricting members 158a becomes small. In addition, when the lower frame 150 and the upper frame 152 act so as to approach the vertical direction as shown in FIG. 3B, the two limiting members 158a have other fixed rotation positions with respect to the fixing members 158b and 158d as fulcrums. The ends slide on the sliding mechanisms 158c and 158e, and the vertical angle α formed by the two restricting members 158a is increased.

  As can be understood by comparing FIG. 3A and FIG. 3B, the horizontal link 158 allows the upper frame 152 to move in the vertical direction relative to the lower frame 150, and moves in the horizontal direction. Limit. Accordingly, it is possible to limit the horizontal swing of the upper frame 152 and the vibration-isolated object 110 that cannot be absorbed by the coil spring 154 and the oil damper 156.

  Returning to FIG. 2, the stopper 160 is formed on two opposing sides corresponding to the outermost sides of the upper frame 152 and the lower frame 150 (here, the sides extended in the y direction where the oil damper 156 is not disposed). Two are arranged opposite each other. Accordingly, the stoppers 160 are provided at a total of four locations. Further, the two stoppers 160 on one side are provided symmetrically with respect to the center of the side as a target point. The stopper 160 has one end fixed to the lower frame 150 and the other end fixed to the upper frame 152, and mechanically limits the relative movement in the vertical direction between the upper frame 152 and the lower frame 150 (sets an upper limit and a lower limit). ).

  FIG. 4 is an explanatory diagram for explaining the stopper 160. The stopper 160 includes a first stopper piece 160 a fixed to the lower frame 150 and a second stopper piece 160 b fixed to the upper frame 152. The first stopper piece 160a includes a pedestal 160h fixed to the lower frame 150, a bolt 160c (rod) fixed to the pedestal 160h and extending in the vertical direction, and two nuts 160d provided apart from the bolt 160c. , 160e (restriction unit). Here, the nuts 160d and 160e are cited as the restricting portions, but various structures can be adopted as long as they protrude in the horizontal direction and have a horizontal area larger than the cross section of the rod. The second stopper piece 160b is formed in the same shape as the base 160h, and a through hole 160f is provided in the center thereof. The second stopper piece 160b is configured to be movable in the vertical direction between the two nuts 160d and 160e in a state where the bolt 160c is inserted through the through hole 160f.

  Here, for example, in a state where the vibration-isolated object 110 is not loaded, the lower frame 150 and the upper frame 152 act in the vertical direction by the elasticity of the coil spring 154 as shown in FIG. Then, the second stopper piece 160b comes into contact with the vertically upper nut 160d and stops at that position. 4B, the second stopper piece 160b moves away from the vertically upper nut 160d, and as the truck 130 moves, the vertically upper nut 160d is loaded. And arbitrarily move between the nut 160e vertically below.

  Further, since the rod body and the restricting portion are formed by bolts 160c and nuts 160d and 160e, the nuts 160d and 160e as the restricting portions are positioned in the longitudinal direction by rotating on the bolt 160c as the rod body. Can be changed. Therefore, the upper limit and the lower limit of the relative movement between the lower frame 150 and the upper frame 152 can be adjusted afterwards, and for example, the upper limit and the lower limit corresponding to the limit of the accommodation space of the truck 130 can be set. .

  Further, since the nuts 160d and 160e are both movable in the longitudinal direction of the bolt 160c, the distance between the nuts 160d and 160e can be shortened, and the second stopper piece 160b is sandwiched between the nuts 160d and 160e. It is also possible to fix the positional relationship between the lower frame 150 and the upper frame 152.

  Further, rubber washers 160g formed of elastic members are provided on the through holes 160f side of the second stopper pieces 160b in the nuts 160d and 160e, respectively, so that the nuts 160d and 160e and the second stopper pieces 160b come into contact with each other. Shock shock.

  Here, the first stopper piece 160a is fixed to the lower frame 150 and the second stopper piece 160b is fixed to the upper frame 152. However, the present invention is not limited to this, and the first stopper piece 160a is fixed to the upper frame 152. The second stopper piece 160b may be fixed to the lower frame 150. Below, the vibration isolation property as the whole vibration isolation pallet 120 is demonstrated.

(Vibration isolation)
As described above, vibration near the sprung resonance frequency accompanying the movement of the track 130 is suppressed through the air suspension of the track 130. However, the vibration in the vicinity of the unsprung resonance frequency that causes slight damage to the vibration isolator 110 cannot be suppressed only by the air suspension. Although the vibration in the vicinity of the unsprung resonance frequency has a short vibration width (amplitude), the vibration energy is large because the frequency is high.

  Therefore, in the vibration isolation pallet 120 according to the present embodiment, vibration of at least the unsprung resonance frequency (10 to 15 Hz) is obtained by a mechanical low-pass filter (low-pass filter) mechanism in which the coil spring 154 and the oil damper 156 are combined. Suppress. Here, the cutoff frequency (cut-off frequency) is set between 10 to 15 Hz which is an unsprung resonance frequency and 1 to 1.5 Hz which is an unsprung resonance frequency. More desirably, a frequency that is less than or equal to the unsprung resonance frequency and that is close to the unsprung resonance frequency is selected as long as it does not affect the unsprung resonance frequency. Here, for example, the cutoff frequency is 2 Hz.

  Here, the reason why the frequency that does not affect the sprung resonance frequency is selected is as follows. If the damping amount of vibration at 10 to 15 Hz which is the unsprung resonance frequency is increased, the cutoff frequency is preferably as low as possible. However, when the cutoff frequency approaches the sprung resonance frequency, resonance with the sprung resonance occurs, which affects the maneuverability of the truck 130 and makes it difficult for the driver of the truck 130 to drive. Therefore, a frequency higher than the sprung resonance frequency is set as the cut-off frequency so as to ensure the maneuverability of the truck 130. In this way, it is possible to improve the vibration isolation effect at a high frequency while utilizing the vibration isolation performance of the air suspension of the truck 130.

(Effectiveness verification)
Hereinafter, the effect of the vibration isolation property of the vibration isolation pallet 120 as a whole will be verified. FIG. 5 is an explanatory diagram comparing the spectral response (spectral distribution) of the vibration-isolated object 110 with respect to vibration before and after the use of the vibration isolation pallet 120 of the present embodiment, and FIG. It is explanatory drawing which compared the time response of the to-be-vibrated object 110 with respect to the vibration before employ | adopting the vibration palette 120, and after employ | adopting.

  FIG. 5A shows the spectral response when the truck 130 is driven at a speed of about 80 km / h on the highway, and FIG. 5B shows the truck 130 at 0 to 45 km / h on the general road. The spectral response when traveling at a moderate speed is shown. Depending on both spectral responses, the vibration of 10 to 15 Hz, which had a high acceleration density before the use of the vibration isolation pallet 120, was suppressed after the vibration isolation pallet 120 was adopted, as indicated by the white arrows. I can grasp.

  Similarly, FIG. 6A shows a time response when the truck 130 is driven at a speed of about 80 km / h on the expressway, and FIG. The time response when traveling at a speed of about 45 km / h is shown. It can be understood that the acceleration (vibration) having a large amplitude before the use of the vibration isolation pallet 120 is suppressed after the vibration isolation pallet 120 is used also by both time responses.

  As described above, the vibration-isolating pallet 120 described above protects the vibration-isolated object 110 with higher vibration-isolation properties from vibration caused by the movement of the truck 130 with an inexpensive configuration, and reduces the commercial value of the vibration-isolated object 110. It becomes possible to suppress.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Is done.

  INDUSTRIAL APPLICABILITY The present invention can be used for a vibration isolation pallet that protects a vibration isolation object from vibration associated with movement of a moving body.

120 ... vibration isolation pallet 130 ... truck (moving body)
150 ... lower frame 152 ... upper frame 154 ... coil spring (elastic member)
156 ... Oil damper (damper)
158 ... Horizontal link 160 ... Stopper

Claims (5)

It is a vibration isolation pallet that is installed on an arbitrary moving body and supports the vibration isolation object from below vertically,
A lower frame which is located on the installation side of the moving body and forms a rigid body extending in the horizontal direction;
An upper frame which is located on the side of the vibration-isolated object and forms a rigid body extending in the horizontal direction;
An elastic member having one end fixed to the lower frame and the other end fixed to the upper frame, and storing kinetic energy received by one frame as elastic energy;
One end is fixed to the lower frame, the other end is fixed to the upper frame, a damper that attenuates the kinetic energy received by one frame and transmits it to the other frame,
With
The cutoff frequency by the vibration isolation pallet is set to a value between the unsprung resonance frequency and the sprung resonance frequency of the moving body.   The vibration isolation pallet according to claim 1, further comprising a horizontal link that restricts a relative movement in a horizontal direction while allowing a relative movement in a vertical direction between the lower frame and the upper frame.   A first stopper piece, which is fixed to one of the lower frame and the upper frame and extends in the vertical direction and is provided with two horizontally projecting portions spaced apart from each other; the lower frame and the lower frame; A stopper having a second stopper piece fixed to the other of the upper frame, inserted into the through hole in the vertical direction, and movable between the two restricting portions is further provided. Item 3. An isolation pallet according to item 1 or 2.   The vibration isolation pallet according to claim 3, wherein the restricting portion is formed to be able to change a position in a longitudinal direction of the rod body.   5. The vibration isolation pallet according to claim 1, wherein the upper frame supports a plurality of separable objects to be separated at different positions in a horizontal direction. 6.

Images