Vibration generator

Abstract

To prevent heat from being transmitted from a vibration test stand to a bearing in a vibration generation device comprising the vibration test stand.SOLUTION: A vibration generation device comprises: a vibration generation unit that generates vibration; a plate-shaped slip table that is connected to the vibration generation unit and vibrates; a plurality of bearings that support the slip table from below so that the slip table can vibrate; a vibration test stand that is housed in an environmental test device, and has a mounting surface on which a test sample can be fixed; a heat insulating cell structure that is disposed between the top surface of the slip table and the bottom surface of the vibration test stand, is integrally connected to the slip table and the vibration test stand, and has a plurality of hollow cells.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a vibration generating device.

Background Art

[0002] Conventionally, there is known a vibration generating device that vibrates a test specimen, which is an object to be tested in a vibration test, by applying vibration in a predetermined direction (for example, the horizontal direction) (see, for example, Patent Document 1 or Patent Document 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a conventional vibration generating device, as disclosed in Patent Document 1, a test specimen (for example, a vibration test body submitted by a producer when requesting a quality inspection) fixed to a slip table is vibrated in a state where the test specimen is directly placed on the slip table.

[0005] When conducting a vibration test using a vibration generating device, in some cases, a vibration test table is arranged in an environmental test device capable of setting predetermined environmental conditions (for example, temperature conditions, humidity conditions, etc.), and the test is conducted with the test specimen placed on the vibration test table. In this case, the temperature inside the environmental test device is transferred as heat to the test specimen and the vibration test table. For example, as an example of the above environmental conditions, a temperature range from -40°C to +180°C is set, and the temperature may vary within this temperature range.

[0006] Vibration test stands are often made of robust, low-density metallic materials, such as aluminum alloys and magnesium alloys. To excite the test stand in a predetermined direction (for example, horizontally), it is connected to a hydrostatic hydraulic bearing or the like, as disclosed in Patent Documents 1 and 2, and slides while supporting the load of the test specimen.

[0007] Conventionally, under the aforementioned environmental conditions, the temperature of the vibration test stand could be transferred to, for example, a hydrostatic hydraulic bearing, causing the hydrostatic hydraulic bearing to malfunction. Therefore, vibration generators equipped with a vibration test stand face the challenge of suppressing the transfer of heat from the vibration test stand to the hydrostatic hydraulic bearing. [Means for solving the problem]

[0008] The vibration generating device of this embodiment, which solves the above problems, comprises a vibration generating unit that generates vibrations, a plate-shaped slip table connected to the vibration generating unit and vibrating, a plurality of bearings that support the slip table from below so that the slip table can vibrate, a vibration test stand housed in an environmental testing device and having a mounting surface on which a test specimen can be fixed, and a heat insulating cell structure disposed between the upper surface of the slip table and the lower surface of the vibration test stand, integrally connected to the slip table and the vibration test stand, and having a plurality of hollow cells. [Effects of the Invention]

[0009] The vibration generating device of this embodiment is equipped with an insulating cell structure having multiple hollow cells between the vibration test stand on which the test specimen is placed and the slip table, thereby suppressing the transfer of heat from the vibration test stand to the bearing (for example, a hydrostatic hydraulic bearing). [Brief explanation of the drawing]

[0010] [Figure 1] This is an illustrative and schematic side view of a vibration generating device. [Figure 2] This is an illustrative and schematic plan view of a vibration generating device. [Figure 3] This is a perspective view showing a first example of a slip table and an insulating cell structure disposed on the slip table. [Figure 4] This is a plan view showing a slip table and a first example of an insulating cell structure arranged on the slip table. [Figure 5] This is a plan view illustrating multiple hydrostatic hydraulic bearings that support a sliptable, enabling smooth and stable vibrational operation of the sliptable. [Figure 6] This is a perspective view illustrating the structure of a hydrostatic hydraulic bearing. [Figure 7] This is a perspective view illustrating the bearing body and movable part of a hydrostatic hydraulic bearing. [Figure 8] This is a perspective view illustrating the lands and pockets formed in the recesses of the bearing body of a hydrostatic hydraulic bearing. [Figure 9] This is a simplified partial cross-sectional view showing a state in which a fluid film is formed between the sliding upper surface of the bearing movable part and a land disposed on the lower surface of the guide plate, and a fluid film is also formed between the land disposed on the bottom surface of the recess of the bearing body and the sliding lower surface of the bearing movable part. [Figure 10] This is a perspective view showing a second example of an insulated cell structure arranged on a slip table. [Figure 11] This is a plan view showing a second example of an insulated cell structure arranged on a slip table. [Figure 12] This is a plan view showing a third example of an insulated cell structure, which is arranged on a slip table and has insulation material filled inside the cell. [Figure 13] This is a plan view showing a fourth example of an insulated cell structure, which is arranged on a slip table and has outlets formed in the side walls of the cells for discharging condensation water. [Modes for carrying out the invention]

[0011] The following diagrams illustrate an exemplary and schematic overview of the vibration generator 1 using Figures 1 and 2. For convenience, directions (X, Y, and Z directions) are defined in each of the following diagrams. The X, Y, and Z directions are orthogonal to each other. For example, the plane formed by the X and Y directions is defined as the horizontal plane, and the Z direction as the vertical direction.

[0012] Figure 1 is an exemplary and schematic side view of the vibration generating device 1 according to this embodiment, and Figure 2 is an exemplary and schematic plan view of the vibration generating device 1. The vibration generating device 1 according to this embodiment is a device that performs vibration tests by forcibly vibrating a test specimen 195. That is, the vibration generating device 1 is a device that performs tests by applying (exciting) vibration in a direction parallel to the surface plate (horizontal direction) to a vibration test stand 50 on which a test specimen 195 is placed and fixed.

[0013] As shown in FIG. 1, the vibration generator 1 includes, for example, a yoke 16 included in a vibration generating unit 14 that generates vibration, a joint 18 connected to the slip table 12, a base 20 that supports the vibration generating unit 14, a plurality of hydrostatic bearings 3 (see FIG. 5), which are an example of bearings, that support the slip table 12 in a non-contact manner from below so that the vibration operation of the slip table 12 can be smoothly and stably performed, the slip table 12, a heat insulation cell structure 4 integrally connected to the upper surface 12a of the slip table 12, and a vibration test table 50 integrally connected to the upper surface of the heat insulation cell structure 4. The fluid used in the hydrostatic bearing 3 shown in FIG. 5 in the embodiment is an incompressible fluid, for example, oil. Further, the bearing included in the vibration generator 1 is not limited to the hydrostatic bearing 3, and may be a cylindrical hydraulic bearing (journal bearing) that forms an oil film between the shaft and the bearing by supplying lubricating oil between the shaft and the bearing and supports the shaft load in a non-contact manner by the oil film force. Further, the bearing included in the vibration generator 1 may be a rolling bearing that inserts rolling elements such as balls or rollers between a shaft, and a ring-shaped inner ring and an outer ring respectively attached to a bearing box, and guides the rotational movement by the rolling contact movement thereof, or a sliding bearing that generates an oil film pressure by allowing a lubricant to be introduced into a wedge-shaped gap formed between the shaft and the bearing by the rotation of the shaft, and thereby supports the rotation and load of the shaft.

[0014] The material of the yoke 16 can be, for example, a magnetic material with high magnetic permeability and high strength, and for example, low carbon steel such as SS400 can be used. For example, the material of the joint 18 disposed on the front side of the vibration generating unit 14 can be, for example, a non-magnetic and high-strength metal such as an aluminum alloy, or a synthetic resin such as carbon fiber. The arrow X1 in FIG. 1 indicates the vibration direction (horizontal direction) of the slip table 12 by the vibration generating unit 14. The slip table 12 is supported by a plurality of hydrostatic bearings 3 (see FIG. 5) so as to be slidable in the direction of the arrow X1.

[0015] The yoke 16 is provided with an exciting coil (not shown) that generates a static magnetic field in the yoke 16 and a drive coil for generating vibration. The drive coil is disposed within the magnetic gap and is integrally formed with the joint 18. By flowing a direct current through the exciting coil, a magnetic circuit (static magnetic field) is generated within the yoke 16 surrounding the exciting coil. Then, by flowing an alternating current of a predetermined frequency through the drive coil, a force acts between the static magnetic field generated in the above-described magnetic gap and the alternating current flowing through the drive coil. Due to this force, the drive coil vibrates in a direction orthogonal to the direction of the magnetic flux. As a result, the joint 18 vibrates at the frequency of the alternating current flowing through the drive coil, and accordingly, the test piece 195 placed and fixed on the slip table 12 via the heat insulation cell structure 4 and the vibration test table 50 vibrates in the direction of arrow X1, and a vibration test is performed.

[0016] As shown in FIGS. 1 to 3, the slip table 12 is detachable via the joint 18 with respect to the vibration generating unit 14 that generates vibration in the direction of arrow X1. The slip table 12 is formed, for example, in a substantially rectangular plate shape in a plan view, and includes a connecting portion 120 that protrudes outward in the horizontal direction, for example, in a trapezoidal shape, on one side of its four sides and serves as a base portion.

[0017] As shown in FIGS. 2 and 3, a plurality of counterboring holes 124 extending obliquely downward are formed side by side in the region of the upper surface 12a of the slip table 12 in the Z direction (vertical direction) that becomes the connecting portion 120. Bolts (not shown) for connecting and fixing the counterboring holes 124 and bolt holes (not shown) on the joint 18 side pass through the counterboring holes 124 and extend from the upper surface 12a to the outer surface of the connecting portion 120.

[0018] The slip table 12 is made of, for example, an aluminum alloy or magnesium alloy with high rigidity and low specific gravity. In this embodiment, it is capable of supporting a test specimen 195 with a maximum mass of approximately 1500 kg, and its thickness is set to, for example, 50 mm. The substantially flat upper surface 12a of the slip table 12 becomes a connecting surface to which the heat insulating cell structure 4 shown in Figures 3 and 4 is integrally connected, and the substantially flat lower surface 12b of the slip table 12 becomes a sliding surface supported by a fluid film (oil film) formed by a plurality of hydrostatic hydraulic bearings 3. For example, around the slip table 12 shown in Figures 1 and 2, a drain pan (not shown) is provided to receive the oil that has formed a fluid film in the hydrostatic hydraulic bearings 3 (see Figure 5) that drips down from the lower surface 12b of the slip table 12.

[0019] In the vibration generator 1 of this embodiment, the hydrostatic hydraulic bearing 3 shown in Figure 5 is housed in, for example, a rectangular, barrel-shaped casing 39 in plan view. The casing 39 comprises a housing chamber 390 capable of housing multiple hydrostatic hydraulic bearings 3, a bottom plate 391, and four side plates 392 erected in the Z direction from the four sides of the upper surface of the bottom plate 391. Each of the side plates 392 extends continuously along the height direction (Z direction) between the slip table 12 shown in Figure 1, which is positioned above the casing 39, and the bottom plate 391, and surrounds the entire lateral circumference of the housing chamber 390.

[0020] As shown in Figure 5, multiple hydrostatic hydraulic bearings 3 are fixed to the upper surface of the bottom plate 391 of the casing 39 at approximately equal intervals in the X and Y directions. The overall hydrostatic hydraulic bearing 3 will be explained using Figure 6. The hydrostatic hydraulic bearing 3, which is made of an aluminum alloy or the like, comprises, for example, a bearing body 30 whose front shape when viewed from the X direction is approximately U-shaped and has a recess 300 that opens in the Z direction toward the slip table 12 shown in Figure 1; a bearing movable part 32 that is non-contact and slidable in the recess 300 that opens toward the slip table 12 in the center of the bearing body 30 by a fluid film (fluid bearing); and a guide plate 34 for smoothly and stably guiding the bearing movable part 32 in the direction of vibration of the slip table 12 (direction of arrow X1 in Figure 1) without generating vibrations in directions other than the direction of arrow X1 (for example, vibrations in directions perpendicular to the direction of arrow X1).

[0021] The bearing movable part 32, which is disposed in the recess 300 of the bearing body 30 shown in Figure 7, is a block body whose frontal shape, when viewed from the X direction, is an inverted T shape. The upper surface of the bearing movable part 32 has a stepped portion 320 that is raised in the center, and the upper surface of the stepped portion 320 is a connecting surface 321 that is bolted to the lower surface 12b of the slip table 12 shown in Figure 1. On both sides of the connecting surface 321 in the Y direction, there are extremely flat sliding upper surfaces 322 that are lower. The lower surface of the bearing movable part 32 is an extremely flat sliding lower surface 323.

[0022] As shown in Figure 8, the bottom surface 307 of the recess 300 in the bearing body 30 is positioned opposite the sliding lower surface 323 of the bearing movable part 32 shown in Figure 7, and has multiple pockets 302 that temporarily store the fluid (oil) supplied to the bearing body 30 from the oil supply port 306. Specifically, in the example shown in Figure 8, four lands 301 of uniform height are formed on the bottom surface 307 of the recess 300 in the bearing body 30 at predetermined intervals in the XY direction, and four pockets 302 are formed surrounded by each of the lands 301. Note that in Figure 8, a portion of the bearing body 30 is cut out to illustrate the pockets 302 and lands 301.

[0023] The pocket 302 can store a certain amount of fluid (oil). The height of the land 301 (height of the pocket 302) can be determined according to the thickness of the fluid film S shown in Figure 9 that is to be formed between the land 301 and the sliding lower surface 323 of the bearing movable part 32.

[0024] As shown in Figure 6, a guide groove 341 is formed between two rectangular guide plates 34, which are bolted to the left and right upper surfaces of the bearing body 30, respectively. This groove extends in the X direction and accommodates the stepped portion 320 of the bearing movable part 32. The bearing body 30 functions as a manifold, distributing fluid (oil) to the guide plates 34 through an oil inlet 306 formed on its side. In addition, multiple nozzles 344 are formed on the upper surface 342 of the guide plates 34, for example, spaced apart in the X direction. These nozzles discharge fluid (oil) onto the lower surface 12b of the slip table 12 shown in Figure 1, forming a fluid film (oil film) between the lower surface 12b and the upper surface 342 of the guide plates 34. The oil film formed on the upper surface 342 of the guide plates 34 is primarily a fluid film that supports the sliding of the slip table 12 and does not receive much load from the slip table 12 side.

[0025] For example, a fluid distribution groove 347 is formed on the upper surface 342 of the guide plate 34 to spread the fluid (oil) supplied to the multiple nozzles 344 in a planar manner. For example, a fluid distribution groove 347 formed in a rectangular ring shape communicates with multiple nozzles 344 and is a groove formed to distribute oil over a wide area of ​​the upper surface 342 of the guide plate 34, forming a wide oil film between the lower surface 12b of the slip table 12 and the upper surface 342 of the guide plate 34, as shown in Figure 1.

[0026] In the lower surface 348 of the guide plate 34 shown in Figure 8, lands 345 and pocket 346 (see Figure 9) are formed in the regions facing the left and right sliding upper surfaces 322 in the Y direction and the Z direction of the bearing movable part 32 (see Figure 7), similar to the lands 301 and pocket 302 of the bearing body 30. A fluid film S (fluid bearing) is then formed between the sliding upper surface 322 of the bearing movable part 32 (see Figure 9) and the fluid film S formed between the sliding upper surface 322 of the bearing movable part 32 and the lower surface 348 of the guide plate 34, and the fluid film S formed between the bottom surface 307 of the recess 300 of the bearing body 30 and the sliding lower surface 323 of the bearing movable part 32. As a result, the bearing movable part 32, which is subjected to loads concentrated from above and below in the Z direction during vibration of the slip table 12, is supported on the bearing body 30 so as to be able to slide non-contact in the direction of arrow X1. In other words, contact between the slip table 12 and the guide plate 34, and contact between the bearing movable part 32 to which the slip table 12 is connected and the guide plate 34 and the bearing body 30 are avoided, and the combination of the slip table 12 and the bearing movable part 32 can be supported by a fluid bearing relative to the combination of the guide plate 34 and the bearing body 30. This reduces micro-vibrations (crosstalk components) other than the normal vibration direction (arrow X1 direction) that occur due to chatter vibrations and resonances of the vibration test stand 50, which is integrally connected to the slip table 12 shown in Figure 1 via an insulating cell structure 4, and the test specimen 195 during vibration testing, thereby enabling highly accurate vibration testing.

[0027] As shown in Figure 6, one or two oil inlets 306 are formed on the outer surface of the bearing body 30. The oil inlets 306 of adjacent hydrostatic hydraulic bearings 3 shown in Figure 5 are connected via connecting pipes 371 such as fittings and resin tubes. For example, as shown in Figure 5, when multiple (e.g., four) hydrostatic hydraulic bearings 3 arranged in the X direction are considered as one bearing row, one end of the connecting pipe 371, which is connected to the outermost hydrostatic hydraulic bearing 3 closest to the side plate 392 of the casing 39, is connected at the other end to the supply pipe 364 of the oil recycling unit 36 ​​via a case oil inlet (not shown). Then, the fluid (oil) supplied from the oil recycling unit 36, which is equipped with a pump, is sequentially supplied to each of the multiple hydrostatic hydraulic bearings 3 that constitute one bearing row. For example, the maximum discharge pressure of the fluid (oil) from the oil recycling unit 36 ​​is 7 MPa, and the actual discharge pressure is 3 MPa to 3.5 MPa. Furthermore, the temperature of the discharged oil is between +15°C and +50°C, more preferably between +20°C and +30°C. The flow rate of the oil discharged by the oil recycling unit 36 ​​is, for example, 40 L / min to 55 L / min.

[0028] As shown in Figure 5, multiple recovery grooves 393 extending vertically and horizontally are cut out in the region between adjacent hydrostatic bearings 3 on the upper surface of the bottom plate 391 of the casing 39. The oil that forms an oil film supporting the slip table 12 in the hydrostatic bearings 3 flows down from the hydrostatic bearings 3 onto the bottom plate 391 of the casing 39 and is pooled in the recovery grooves 393 which are located lower than the upper surface of the bottom plate 391. Therefore, the structure makes it difficult for the hydrostatic bearings 3 to be immersed in the oil accumulated on the upper surface of the bottom plate 391 within the casing 39. An outlet 395 is formed at the bottom of the recovery groove 393, and a return passage 369 consisting of a drain hose or the like is connected to the outlet 395. The recovery grooves 393 may be formed in a grid pattern on the bottom plate 391 so as to surround all four sides of all the hydrostatic bearings 3. Furthermore, for example, the depth of the recovery groove 393 is set so that the area where the discharge port 395 is formed is deeper than other areas, thereby suppressing the entrainment of air when oil is discharged from the discharge port 395.

[0029] Below the casing 39 (shown on the side for illustrative purposes in Figure 5), an oil recycling unit 36 ​​is provided to circulate the fluid (oil) supplied to the hydrostatic hydraulic bearings 3. The oil recycling unit 36 ​​houses a storage tank, a suction filter, a pump, a relief valve, and a switching valve, etc. The storage tank stores the oil as the fluid circulating within the circulation system. The suction filter removes foreign matter from the circulating oil and purifies it. The pump sends oil from the storage tank to the supply piping 364 at a predetermined pressure through the relief valve, switching valve, etc., and supplies it to the multiple hydrostatic hydraulic bearings 3 inside the casing 39.

[0030] The vibration generator 1 is equipped with an oil temperature control unit 368, schematically shown in Figure 5. The oil temperature control unit 368, which is equipped with a CPU and memory elements, sends control signals to the electrically connected oil recycling unit 36, and can control the pressure, temperature, and flow rate of the fluid (oil) discharged by the oil recycling unit 36.

[0031] The oil pooled in the recovery groove 393 of the casing 39 is sucked up by the negative pressure generated by the pump of the oil recycling unit 36, returned to the storage tank of the oil recycling unit 36 ​​via the return path 369, filtered by a suction filter, adjusted to a suitable temperature, and then supplied again to the hydrostatic hydraulic bearing 3 for reuse.

[0032] As in this embodiment, a recovery groove 393 for pooling used oil from the hydrostatic hydraulic bearing 3 is formed in the bottom plate 391 of the casing 39. This prevents used oil (oil after fluid film formation) from accumulating on the bottom plate 391 of the casing 39, thereby preventing the entire hydrostatic hydraulic bearing 3 from being immersed in used oil. As a result, the hydrostatic hydraulic bearing 3 is less affected by the temperature of the used oil and the temperature of the casing 39, and the temperature of the hydrostatic hydraulic bearing 3 itself is maintained at a temperature close to the temperature of the suitable oil newly supplied from the oil recycling unit 36. Therefore, for example, even if the temperature of the oil circulating in the vibration generator 1 by the oil recycling unit 36 ​​changes between the time of supply to the hydrostatic hydraulic bearing 3 and after use (for example, rising after fluid film formation) depending on the vibration test conditions, the hydrostatic hydraulic bearing 3 can still form a fluid film with oil at a suitable predetermined temperature.

[0033] The environmental testing apparatus 19, simplified by a dashed line in Figure 1, can artificially recreate various environmental conditions that the test specimen 195 will experience during use within the apparatus housing 190. Examples include a constant temperature and humidity chamber or a prefabricated refrigerator / freezer that can control the temperature and humidity inside the apparatus housing 190. A frame hole (not shown) is formed on the lower surface of the apparatus housing 190, capable of accommodating, for example, a vibration test stand 50. The environmental testing apparatus 19 is attached to the vibration test stand 50 with the vibration test stand 50 housed inside the apparatus housing 190 through the frame hole. For example, a sealing member 193 (e.g., silicone rubber) is placed in the frame hole to seal it and prevent any gaps between the frame hole and the vibration test stand 50. The temperature inside the apparatus housing 190 can be adjusted, for example, within a range of approximately -40°C to approximately +180°C, and the sealing member 193 restricts most of the heat transfer from inside the environmental testing apparatus 19 to the vibration test stand 50.

[0034] The vibration test stand 50 is, for example, a plate-shaped member capable of fixing the test specimen 195, which is the subject of the vibration test, to a substantially flat mounting surface 500 on its upper surface. In this embodiment, the vibration test stand 50 is formed in a rectangular shape in plan view, for example, 2500 mm in length and 2500 mm in width, and is set to have a larger area than conventional models. Also, for example, the thickness of the vibration test stand 50 is set to 30 mm. The vibration test stand 50 is formed of, for example, an aluminum alloy or magnesium alloy, which has high rigidity and low specific gravity.

[0035] As shown in Figure 2, the mounting surface 500 of the vibration test stand 50 has, for example, a matrix of fixing screw holes (not shown) formed on it for fixing the test specimen 195. The test specimen 195 can be fixed directly using the fixing screw holes (not shown), or it can be fixed via a jig or the like. Note that the method of fixing the test specimen 195 on the vibration test stand 50 is just one example, and it may also be done by means of adsorption using air suction or electromagnetic force, for example. In the vibration generator 1 of this embodiment, a heat insulating cell structure 4 is integrally formed on the slip table 12, and the vibration test stand 50 is fixed on the heat insulating cell structure 4, resulting in a three-layer integrated laminated structure. Therefore, the vibration test stand 50 has high bending rigidity and achieves a larger surface area than conventional models.

[0036] As shown in Figure 2, the mounting surface 500 of the vibration test stand 50 has, for example, a matrix of counterbore holes 503 formed horizontally offset from the aforementioned fixing screw holes (not shown). The counterbore holes 503 penetrate the vibration test stand 50 in the thickness direction, and the lower surface 502 of the vibration test stand 50 is brought into contact with the upper surface of the heat insulating cell structure 4, so that the corresponding bolt holes (not shown) of the heat insulating cell structure 4 are aligned with the counterbore holes 503 of the vibration test stand 50, and bolts are passed through the counterbore holes 503 and bolt holes from above and screwed in, so that the bolt heads do not protrude from the mounting surface 500. The vibration test stand 50 and the heat insulating cell structure 4 are then fastened together and integrated.

[0037] The thermal insulation cell structure 4 shown in Figures 3 and 4 (hereinafter referred to as the first example of thermal insulation cell structure 4) is formed integrally with the slip table 12, for example, by cutting out a portion in the thickness direction (Z direction) of the slip table 12, which has an extra thickness for forming the thermal insulation cell structure 4 in advance. The thermal insulation cell structure 4 has a plurality of side walls 41 extending in the X direction in the region of the upper surface 12a of the slip table 12 excluding the connecting portion 120. That is, the side walls 41 are erected on the upper surface 12a of the slip table 12 at equal intervals in the X direction. A plurality of connecting walls 42 are formed integrally with the side walls 41 between adjacent side walls 41.

[0038] The height of the side wall 41 and the height of the connecting wall 42 are set to be the same, and the connection points between the side wall 41 and the connecting wall 42 intersect integrally in a cross shape. Multiple side walls 41 and multiple connecting walls 42 divide the upper surface 12a of the slip table 12 into a grid shape, forming multiple rectangular thermal insulation spaces called cells 43 in plan view. In other words, the thermal insulation cell structure 4 is a hollow structure comprising multiple cells 43. Furthermore, for example, the thermal insulation cell structure 4 is set to be about the same size as the vibration test stand 50, or slightly smaller.

[0039] For example, bolt holes 47 corresponding to the respective counterbore holes 503 of the vibration test stand 50 are formed on the upper surfaces of each side wall 41 and the connecting wall 42, and the vibration test stand 50 is fastened and fixed to the upper surfaces of the side walls 41 and the connecting wall 42 by bolts (not shown). When fixing the vibration test stand 50 to the heat insulating cell structure 4, the inside of each cell 43 of the heat insulating cell structure 4 may be made into a vacuum atmosphere. The heat insulating cell structure 4 may also be a heat insulating plate on which the above-mentioned multiple cells 43 are formed on a bottom plate, and which is detachably attached to the upper surface 12a of the slip table 12 by bolts. Furthermore, the heat insulating cell structure 4 may be made of a metal with lower thermal conductivity than the vibration test stand 50, for example.

[0040] In the thermal insulation cell structure 4 of the vibration generating device 1 of this embodiment, the cell 43 is formed in a rectangular shape in plan view, and its longitudinal direction is in the X direction, parallel to arrow X1 (the vibration excitation direction of the slip table 12 by the vibration generating unit 14). While it is preferable to make the longitudinal direction of the cell 43 parallel to the vibration excitation direction of the slip table 12 in this way, as it improves the thermal insulation efficiency of the thermal insulation cell structure 4, the shape of the cell 43 is not limited to a rectangular shape in plan view, and may be formed in a square shape or the like in plan view.

[0041] The number of cells 43 in the heat-insulating cell structure 4 is set to an appropriate number, for example, corresponding to the number of hydrostatic hydraulic bearings 3 shown in Figure 5 that are provided in the vibration generator 1. In a specific example, as shown in Figures 3 and 4, a total of 36 cells 43 are formed, with 4 in the X direction and 9 in the Y direction. In the example shown in Figure 4, one hydrostatic hydraulic bearing 3 is located below each of the two outermost cells 43 in the Y direction, and three hydrostatic hydraulic bearings 3 are positioned below the remaining seven cells 43 at approximately equal intervals. In particular, the hollow space of the cell 43 overlaps (opposes) over a wide area when viewed from the Z direction with the sliding upper surface 322 and sliding lower surface 323 of the bearing movable part 32 shown in Figure 6 of the hydrostatic hydraulic bearing 3. Note that in Figure 4, only the hydrostatic hydraulic bearings 3 forming one row in the Y direction are shown for clarity, but hydrostatic hydraulic bearings 3 are positioned below the cells 43 in approximately the same way in the X direction. Furthermore, by providing multiple cells 43, the number of side walls 41 and connecting walls 42 increases, which increases the area on which the vibration test stand 50 fixed to the heat-insulating cell structure 4 can be fixedly supported, preventing the central region of the vibration test stand 50, which is susceptible to load from the test specimen 195, from bending downward.

[0042] In the heat-insulating cell structure 4 shown in Figures 3 and 4, bolt insertion holes (not shown) are formed through multiple cells 43 in the thickness direction of the slip table 12. The lower surface 12b of the slip table 12 is brought into contact with the connecting surfaces 321 of each bearing movable part 32 of, for example, a total of 20 hydrostatic hydraulic bearings 3 shown in Figure 5, thereby appropriately aligning the slip table 12 on the multiple hydrostatic hydraulic bearings 3. Then, the corresponding bolt insertion holes of the slip table 12 and the corresponding bolt holes 326 of the connecting surfaces 321 are aligned, and bolts are passed through the bolt insertion holes and bolt holes 326 (not shown) from above and screwed in. In this way, the bearing movable part 32, which is slidable on the bearing body 30 by a fluid film, and the slip table 12 are connected and integrated.

[0043] In the first example of the insulated cell structure 4, each side wall 41 forming a plurality of cells 43 has a temperature-controlled fluid inlet 411 for introducing a temperature-controlled fluid (e.g., a gas such as air or a liquid such as water) into the cell 43, and a temperature-controlled fluid outlet 412 for releasing the temperature-controlled fluid from inside the cell 43. The temperature-controlled fluid inlet 411 and the temperature-controlled fluid outlet 412 penetrate the side wall 41 in the Y direction. The temperature-controlled fluid outlet 412 of one cell 43 functions as a temperature-controlled fluid inlet 411 in another cell 43 located next to this cell 43 and downstream in the direction of flow of the temperature-controlled fluid L shown in Figure 3.

[0044] If a temperature-regulating fluid (temperature-controlled fluid L) is flowed within the insulated cell structure 4, then, for example, temperature sensors 509 may be embedded in several locations on the lower surface 502 of the vibration test stand 50 shown in Figure 1, preferably in several locations on the lower surface 502 corresponding to the hydrostatic hydraulic bearing 3 (see Figure 5). The temperature sensors 509 are equipped with, for example, a thermistor, thermocouple, or resistance thermometer, and measure the temperature of the vibration test stand 50 to which heat is conducted from the environmental test apparatus 19.

[0045] Furthermore, the vibration generator 1 is equipped with a temperature control unit 499, schematically shown in Figures 3 and 4. The temperature control unit 499, which is equipped with a CPU and memory elements such as memory, sends control signals to an electrically connected temperature control fluid supply source 49 and can control at least the temperature of the temperature control fluid L supplied by the temperature control fluid supply source 49. The temperature control unit 499 receives measurement information sequentially from, for example, a temperature sensor 509 located on the lower surface 502 of the vibration test stand 50.

[0046] As shown in Figures 3 and 4, multiple (e.g., nine) cells 43 arranged in the Y direction constitute one cell row 44. That is, the first example of adiabatic cell structure 4 has four cell rows 44. For example, among the cell rows 44 of the adiabatic cell structure 4 attached to the slip table 12, the cell row 44 closest to the connecting portion 120 is designated as the first cell row 44. Multiple temperature-controlled fluid inlets 411 and multiple temperature-controlled fluid outlets 412 in the first cell row 44 are formed at approximately the same position on their respective side walls 41, and each faces the other in the Y direction. Therefore, the flow of temperature-controlled fluid L supplied from the temperature-controlled fluid supply source 49 and passing through the multiple temperature-controlled fluid inlets 411 and temperature-controlled fluid outlets 412 of the multiple cells 43 constituting the first cell row 44 is linear from the upstream side (+Y direction side) to the downstream side (-Y direction side).

[0047] In the insulated cell structure 4, the multiple temperature-controlled fluid inlets 411 and multiple temperature-controlled fluid outlets 412 of the second row of cells 44, located next to the first row of cells 44, are formed at approximately the same positions on their respective side walls 41, and each faces the other in the Y direction. The temperature-controlled fluid L supplied to the second row of cells 44 from the temperature-controlled fluid supply source 49 flows linearly from the -Y direction (upstream) to the +Y direction (downstream). In other words, the flow direction of the temperature-controlled fluid L is set to be opposite in the Y direction between the first row of cells 44 and the second row of cells 44.

[0048] The temperature-controlled fluid L supplied from the temperature-controlled fluid supply source 49 to the third row of cells 44 flows linearly from the +Y direction (upstream) towards the -Y direction (downstream), passing through the temperature-controlled fluid inlet 411 and temperature-controlled fluid outlet 412 of each cell 43. Similarly, the temperature-controlled fluid L supplied from the temperature-controlled fluid supply source 49 to the fourth row of cells 44 flows linearly from the -Y direction (upstream) towards the +Y direction (downstream), passing through the temperature-controlled fluid inlet 411 and temperature-controlled fluid outlet 412 of each cell 43. Thus, in the first example of adiabatic cell structure 4, the temperature-controlled fluid L is supplied from the temperature-controlled fluid supply source 49 to the temperature-controlled fluid inlet 411 such that the direction of flow of the temperature-controlled fluid L from the temperature-controlled fluid inlet 411 to the temperature-controlled fluid outlet 412 in one cell row 44 is opposite (alternating left and right) to the direction of flow of the temperature-controlled fluid L from the temperature-controlled fluid inlet 411 to the temperature-controlled fluid outlet 412 in another cell row 44 located next to the first cell row 44.

[0049] Alternatively, multiple cells 43 aligned in the X direction may be treated as a single cell row, and a temperature-controlled fluid inlet 411 and a temperature-controlled fluid outlet 412 may be formed in the connecting wall 42 to allow the temperature-controlled fluid L to flow in the X direction. Furthermore, the flow direction of the temperature-controlled fluid L may be set to be opposite in one adjacent cell row and the cell row located next to this cell row in the Y direction.

[0050] For example, among the multiple cells 43 that make up each cell row 44, a temperature-controlled fluid inlet 411 formed on the side wall 41 of the cell 43 located furthest out in the Y direction is connected to the temperature-controlled fluid supply source 49, which includes a pump or compressor and a tank, via piping and a solenoid valve, etc.

[0051] For example, if the temperature-controlled fluid L supplied by the temperature-controlled fluid supply source 49 shown in Figures 3 and 4 is air, the temperature-controlled fluid supply source 49 may supply air adjusted to the desired temperature to the cell 43 from a temperature-controlled fluid inlet 411 formed on the side wall 41 of the outermost cell 43 in the Y direction, pass it through multiple cells 43 in sequence, and release it to the atmosphere through an exhaust hose or the like from the temperature-controlled fluid outlet 412 of the last cell 43 of one cell row 44.

[0052] Furthermore, among the multiple cells 43 constituting one cell row 44, the temperature-controlled fluid L (air) that has passed through the temperature-controlled fluid outlet 412 formed on the side wall 41 of the cell 43 located furthest out in the Y direction may flow into the temperature-controlled fluid inlet 411 of another cell row 43 constituting a different cell row 44 located next to the first cell row 44.

[0053] For example, if the temperature-controlled fluid L supplied by the temperature-controlled fluid supply source 49 is a liquid such as water, the temperature-controlled fluid supply source 49 may supply the temperature-controlled fluid L (water) adjusted to the desired temperature to the cell 43 from a temperature-controlled fluid inlet 411 formed on the side wall 41 of the outermost cell 43 in the Y direction, pass it through multiple cells 43 in sequence, and return it to the temperature-controlled fluid supply source 49 from the temperature-controlled fluid outlet 412 of the last cell 43 of one cell row 44 via a return hose or the like, and then adjust the temperature of the temperature-controlled fluid (water) again within the temperature-controlled fluid supply source 49 before circulating it to the cells 43 of the insulated cell structure 4.

[0054] Furthermore, among the multiple cells 43 constituting one cell row 44, the temperature-controlled fluid L (water) that has passed through the temperature-controlled fluid outlet 412 formed on the side wall 41 of the cell 43 located furthest out in the Y direction may flow into the temperature-controlled fluid inlet 411 of another cell row 43 constituting a different cell row 44 located next to the first cell row 44.

[0055] The vibration generator 1 may be equipped with a second example of an insulated cell structure 4A, as shown in Figures 10 and 11, instead of the first example of an insulated cell structure 4. In the second example of an insulated cell structure 4A, components similar to those in the first example of an insulated cell structure 4, as shown in Figures 3 and 4, will be described using the same reference numerals as in the first example of an insulated cell structure 4. In the insulated cell structure 4A, the direction of flow of the temperature-controlled fluid L supplied from the temperature-controlled fluid supply source 49 from the temperature-controlled fluid inlet 414 to the temperature-controlled fluid outlet 415 in one cell row 44, as shown in Figures 10 and 11, is opposite (alternating left and right).

[0056] In the second example of the insulated cell structure 4A, the temperature-controlled fluid outlet 415 and temperature-controlled fluid inlet 414 shown in Figures 10 and 11 are formed on the side wall 41 offset from each other so as not to face each other in the direction (Y direction) of the arrangement of cells 43 forming the cell row 44. Specifically, for example, in a cell 43 constituting one cell row 44, the temperature-controlled fluid outlet 415 is formed at the position furthest from the temperature-controlled fluid inlet 414. For example, in two side walls 41 facing each other in the Y direction, the temperature-controlled fluid inlet 414 is formed in the region immediately next to one corner of a rectangular cell 43 in plan view on one side wall 41, while the temperature-controlled fluid outlet 415 is formed in the region immediately next to the diagonal of the aforementioned corner of a rectangular cell 43 in plan view on the other side wall 41. In this way, in each cell 43, the temperature-controlled fluid inlet 414 and the temperature-controlled fluid outlet 415 are formed diagonally opposite each other and offset from each other so as not to face each other in the Y direction. For example, if the temperature-controlled fluid inlet 414 is formed at the highest position in the Z direction of one side wall 41 forming a single cell 43, the temperature-controlled fluid outlet 415 is formed at the lowest position in the Z direction of the other side wall 41.

[0057] Alternatively, multiple cells 43 aligned in the X direction may be treated as a single cell row, and temperature-controlled fluid inlets 414 and outlets 415 may be formed on the connecting wall 42, offset from each other so as not to face each other in the X direction, allowing the temperature-controlled fluid L to flow in the X direction. Furthermore, the flow direction of the temperature-controlled fluid L may be reversed between adjacent cell rows in the X direction and the cell row located next to this row.

[0058] The following describes an experiment in which a test specimen 195, fixed on a vibration test stand 50 housed within an environmental testing apparatus 19, is vibrated using the vibration generator 1 shown in Figures 1 and 2. The vibration test stand 50 is housed within the apparatus casing 190 of the environmental testing apparatus 19, and the test specimen 195 is fixed to the mounting surface 500 of the vibration test stand 50, for example, with bolts.

[0059] The joint 18 shown in Figure 1 vibrates at the frequency of the alternating current flowing through the drive coil of the yoke 16 of the vibration generating unit 14. Consequently, the slip table 12 vibrates in the direction of arrow X1, and the test specimen 195, which is mounted and fixed on the slip table 12 via the heat-insulating cell structure 4 and the vibration test stand 50, also vibrates in the direction of arrow X1, thereby conducting a vibration test.

[0060] Furthermore, as the slip table 12 vibrates in the direction of arrow X1, a fluid film (oil film) is formed on the upper surface 342 of the guide plate 34 of the hydrostatic hydraulic bearing 3 shown in Figures 5-6 and 9, as explained earlier. Additionally, a fluid film S shown in Figure 9 is formed between the sliding upper surface 322 of the bearing movable part 32 and the lower surface 348 of the guide plate 34, and between the bottom surface 307 of the recess 300 of the bearing body 30 and the sliding lower surface 323 of the bearing movable part 32. This allows the hydrostatic hydraulic bearing 3 to vibrate and support the lower surface 12b of the slip table 12 shown in Figure 1. The connected and integrated slip table 12, the heat-insulating cell structure 4, and the vibration test stand 50 generate force moments in various directions due to the vibration test. On the other hand, the slip table 12 connected to the bearing movable part 32 is supported non-contact in the Z direction by a fluid film S mainly shown in Figure 9, formed by a plurality of hydrostatic hydraulic bearings 3, and this fluid film S makes it possible to generate a strong counterforce on the slip table 12. This counterforce can be changed to a desired magnitude by changing the pressure of the supplied fluid (oil). Therefore, by adjusting the oil pressure, it is possible to effectively suppress vibrations other than those in the vibration direction of the slip table 12 on which the test specimen 195 is placed, and the accuracy of the vibration test can be further improved.

[0061] The temperature inside the apparatus housing 190 of the environmental testing apparatus 19, which houses the vibration test stand 50 shown in Figure 1, fluctuates within a range of approximately -40°C to approximately +180°C. Therefore, the temperature of the vibration test stand 50 inside the apparatus housing 190 also fluctuates due to heat transfer within a range of approximately -40°C to approximately +180°C. The appropriate oil temperature for the hydrostatic hydraulic bearing 3 depends on the type of oil used, but is typically in the range of +20°C to +25°C, within which the oil often achieves the desired viscosity. In other words, there is a significant difference from the temperature of the above-mentioned environmental conditions (-40°C to +180°C). Therefore, in conventional vibration generators, heat is transferred from the vibration test stand to the hydrostatic hydraulic bearing, causing thermal expansion or contraction of the hydrostatic hydraulic bearing itself due to temperature changes in the fluid (oil) constituting the hydrostatic hydraulic bearing, which can prevent the hydrostatic hydraulic bearing from functioning properly. In contrast, in the vibration generator 1 of this embodiment, the vibration test stand 50 is connected to the slip table 12 with a first example of a heat insulating cell structure 4 having a plurality of hollow cells 43, as shown in Figures 3 and 4, in between. As a result, the plurality of cells 43 act as a heat insulating layer, suppressing the transfer of heat from the vibration test stand 50, which has become hot, to the slip table 12. Furthermore, even if the bearings equipped in the vibration generator 1 are not hydrostatic hydraulic bearings 3 but rather bearings that use oil, such as journal bearings or sliding bearings, the heat insulating cell structure 4 can suppress the transfer of heat from the vibration test stand 50 to the bearings, allowing the bearings to function properly. In addition, even if the bearings equipped in the vibration generator 1 are rolling bearings or the like, the heat insulating cell structure 4 can suppress the transfer of heat from the vibration test stand 50 to the bearings, preventing bearing expansion and allowing the bearings to function properly.

[0062] For example, in this embodiment, in order to improve the thermal insulation efficiency of the thermal insulation cell structure 4, a temperature-controlled fluid L, which is heated to a predetermined temperature and supplied by a temperature-controlled fluid supply source 49 shown in Figures 3 and 4, is supplied to each cell 43. For example, consider a case where the temperature inside the environmental test apparatus 19 shown in Figure 1 rises and the temperature of the vibration test stand 50 exceeds a predetermined threshold.

[0063] In this case, for example, a temperature sensor 509 attached to the lower surface 502 of the vibration test stand 50 shown in Figure 1 measures when the temperature of the vibration test stand 50 exceeds a predetermined threshold, and the measurement information is sent from the temperature sensor 509 to the temperature control fluid temperature control unit 499 shown in Figures 3 and 4. In addition, the hydrostatic hydraulic bearing 3 shown in Figure 5 is supplied with oil from the oil recycling unit 36, which has been adjusted to a temperature suitable for forming each fluid film (oil film) by the oil temperature control unit 368.

[0064] If the temperature of the vibration test stand 50 exceeds a predetermined threshold, and heat is transferred from the vibration test stand 50 to the hydrostatic hydraulic bearing 3 via the slip table 12, exceeding the thermal insulation performance of the insulated cell structure 4, the viscosity of the oil forming the fluid film in the hydrostatic hydraulic bearing 3 will decrease, potentially preventing the hydrostatic hydraulic bearing 3 from forming a suitable fluid film to support the slip table 12.

[0065] Therefore, the temperature control unit 499, shown in Figures 3 and 4, which receives measurement information from the temperature sensor 509, sends a control signal to the temperature control fluid supply source 49 to lower the temperature of the temperature control fluid L supplied from the temperature control fluid supply source 49 to the adiabatic cell structure 4. As a result, the temperature control fluid L at a lower temperature passes through the multiple cells 43 of the adiabatic cell structure 4, thereby suppressing the transfer of heat from the vibration test stand 50, which has reached a temperature exceeding a predetermined threshold, to the multiple hydrostatic hydraulic bearings 3 via the adiabatic cell structure 4 and the slip table 12.

[0066] The effect of supplying a temperature-controlled fluid L from a temperature-controlled fluid supply source 49 to the first example of adiabatic cell structure 4 shown in Figures 3 and 4, and setting the flow direction of the temperature-controlled fluid L from the temperature-controlled fluid inlet 411 to the temperature-controlled fluid outlet 412 in one cell row 44 to be in opposite directions, will be explained.

[0067] For example, the temperature-controlled fluid L supplied to the insulated cell structure 4 may have a temperature gradient that changes each time it passes through each cell 43 constituting one cell row 44. In this case, on the insulated cell structure 4, the direction of flow of the temperature-controlled fluid L from the temperature-controlled fluid inlet 411 to the temperature-controlled fluid outlet 412 in one cell row 44 (for example, flowing from the +Y direction to the -Y direction) and the direction of flow of the temperature-controlled fluid L from the temperature-controlled fluid inlet 411 to the temperature-controlled fluid outlet 412 in another cell row 44 located next to the first cell row 44 (for example, flowing from the -Y direction to the +Y direction) are opposite. As a result, the temperature gradient in the direction of flow of the temperature-controlled fluid L tends to be opposite in one cell row 44 and in the other cell row 44 located next to it. Therefore, the temperature adjustment of the insulated cell structure 4 by the temperature-controlled fluid L can be made uniform throughout the entire insulated cell structure 4, and it is possible to prevent some hydrostatic hydraulic bearings 3 from receiving heat from the vibration test stand 50 and experiencing a temperature rise.

[0068] Next, we will describe the case where the second example of an insulated cell structure 4A, shown in Figures 10 and 11, is placed between the slip table 12 and the vibration test stand 50 shown in Figure 1, instead of the first example of an insulated cell structure 4. In this case, on the insulated cell structure 4A, the direction of flow of the temperature-controlled fluid L from the temperature-controlled fluid inlet 414 to the temperature-controlled fluid outlet 415 in one cell row 44 (for example, the direction of flow from the +Y direction to the -Y direction) is reversed from the direction of flow of the temperature-controlled fluid L from the temperature-controlled fluid inlet 414 to the temperature-controlled fluid outlet 415 in another cell row 44 located next to the first cell row 44 (for example, the direction of flow from the -Y direction to the +Y direction). As a result, the temperature gradient in the direction of flow of the temperature-controlled fluid L tends to be in the opposite direction, and the temperature control by the temperature-controlled fluid L can be made uniform throughout the entire insulated cell structure 4A. Furthermore, in each cell 43, the temperature-controlled fluid outlets 415 are formed on the side walls 41 so as to be offset from the temperature-controlled fluid inlets 414 in the Y direction, thereby making the temperature of the temperature-controlled fluid L within each cell 43 more uniform. That is, it is possible to suppress the temperature-controlled fluid L that flows into the cell 43 from the temperature-controlled fluid inlet 414 from flowing the shortest distance within the cell 43 and flowing from the temperature-controlled fluid outlet 415 to the next cell 43, and instead the temperature-controlled fluid L spreads throughout the entire cell 43 before reaching the temperature-controlled fluid outlet 415 and flowing to the next cell 43. In other words, when viewing the flow of the temperature-controlled fluid L across an entire cell row 44 in a plan view, the flow of the temperature-controlled fluid L becomes zigzag. Therefore, the temperature control by the temperature-controlled fluid L for the adiabatic cell structure 4A can be made even more uniform across the entire adiabatic cell structure 4A. Thus, it is possible to further suppress the temperature rise of only a specific hydrostatic hydraulic bearing 3 among the multiple hydrostatic hydraulic bearings 3 due to receiving heat from the vibration test stand 50.

[0069] The vibration generating device 1 may be equipped with a third example of an insulating cell structure 4B shown in Figure 12, instead of the first example of an insulating cell structure 4 shown in Figures 3 and 4. In the third example of an insulating cell structure 4B, components similar to those in the first example of an insulating cell structure 4 shown in Figures 3 and 4 will be described using the same reference numerals as those used in the first example of an insulating cell structure 4.

[0070] The third example of the insulated cell structure 4B is used without passing a temperature-controlled fluid through it. Furthermore, since condensation may easily occur in each cell 43 of the insulated cell structure 4B depending on the vibration test conditions, for example, each cell 43 of the insulated cell structure 4B is filled with an insulating material 468. The insulating material 468 is in contact with, for example, the upper surface 12a of the slip table 12, the side wall 41, the connecting wall 42, and the lower surface 502 of the vibration test stand 50 (see Figure 1) within the cell 43. Examples of insulating material 468 include silicone sponge sheets with heat resistance (-60℃ to +200℃), rigid polyurethane foam, or polystyrene foam, which are foamed plastics. In the insulated cell structure 4B, the filling of the cells 43 with insulating material 468 in this way suppresses the occurrence of condensation in the cells 43 and maintains the insulating function of the insulated cell structure 4B.

[0071] The vibration generating device 1 may be equipped with the fourth example of an insulating cell structure 4C shown in Figure 13, instead of the first example of an insulating cell structure 4 shown in Figures 3 and 4. In the fourth example of an insulating cell structure 4C, components similar to those in the first example of an insulating cell structure 4 shown in Figures 3 and 4 will be described using the same reference numerals as those in the first example of an insulating cell structure 4.

[0072] The insulated cell structure 4C shown in Figure 13 has outlets 461 formed through the side walls 41 and connecting walls 42 of each cell 43 to discharge condensation water generated inside the cell 43. The condensation water that passes through the outlets 461 of each cell 43 can be drained from the outer periphery of the insulated cell structure 4C to a drain pan (not shown) outside the device. Note that the outlets 461 may be formed through at least one of the side walls 41 or the connecting walls 42.

[0073] For example, if the vibration generator 1 is equipped with the first example of adiabatic cell structure 4 shown in Figures 3 and 4, or the second example of adiabatic cell structure 4A shown in Figures 10 and 11, the temperature control unit 499 may adjust the temperature of the temperature-controlled fluid L supplied by the temperature-controlled fluid supply source 49 when it flows into the cell 43 (inlet temperature) to correspond to a suitable temperature of the oil when the hydrostatic hydraulic bearing 3 forms a fluid film supporting the slip table 12, which has been experimentally, empirically, or theoretically determined.

[0074] For example, the vibration generator 1 may be equipped with a displacement sensor 60 that measures the displacement of the fluid film S in the thickness direction (Z direction) relative to the bottom surface 307 of the recess 300 of the bearing body 30 on the sliding lower surface 323 of the bearing movable part 32 of the hydrostatic hydraulic bearing 3 shown in Figures 7 to 9. The displacement of the sliding lower surface 323 relative to the bottom surface 307 in the Z direction is, in other words, the change in the thickness of the fluid film S formed between the sliding lower surface 323 and the bottom surface 307. Note that the thickness of the fluid film S formed between the lower surface 348 of the guide plate 34 and the sliding upper surface 322 of the bearing movable part 32 shown in Figure 9 is approximately the same as the thickness of the fluid film S formed between the sliding lower surface 323 and the bottom surface 307.

[0075] The displacement sensor 60 is preferably an eddy current type displacement sensor that measures displacement using a high-frequency magnetic field, but it may also be a capacitive displacement sensor, an ultrasonic displacement sensor, a reflective photoelectric sensor, etc. Multiple displacement sensors 60 are installed on the hydrostatic hydraulic bearings 3, for example. For example, they are installed on a total of four hydrostatic hydraulic bearings 3 located at the four corners of the casing 39 of the multiple hydrostatic hydraulic bearings 3 shown in Figure 5. For example, when installing the displacement sensor 60 on the hydrostatic hydraulic bearings 3, a cable relief groove 398 may be formed in the bottom plate 391 of the casing 39 shown in Figure 5 for routing a sensor cable (not shown) that is electrically connected to the displacement sensor 60.

[0076] For example, as shown in Figure 8, the displacement sensor 60 is positioned in the Z-direction opposite the sliding lower surface 323 of the bearing movable part 32, which is located in the recess 300 of the bearing body 30. For example, it is embedded in the central area of ​​the recess 300. The displacement sensor 60 is protected from contact with oil by a cover (not shown).

[0077] In a state where a fluid film is formed on the upper surface 342 of the guide plate 34 of the hydrostatic hydraulic bearing 3, and a fluid film S is formed between the sliding upper surface 322 of the bearing movable part 32 and the lower surface 348 of the guide plate 34, and between the bottom surface 307 of the recess 300 of the bearing body 30 and the sliding lower surface 323 of the bearing movable part 32, and the hydrostatic hydraulic bearing 3 is vibrably supporting the lower surface 12b of the slip table 12, the displacement sensor 60 measures the displacement of the sliding lower surface 323 of the bearing movable part 32 in the Z direction, for example with the bottom surface 307 of the recess 300 as the origin height, and sequentially transmits the measurement information to the oil temperature control unit 368 shown in Figure 5, for example.

[0078] The measurement information regarding the above displacement can be considered identical to the information regarding the change in the thickness of the fluid film S formed between the sliding upper surface 322 of the bearing movable part 32 and the lower surface 348 of the guide plate 34, and the change in the thickness of the fluid film S formed between the sliding lower surface 323 and the bottom surface 307. The oil temperature control unit 368 stores, for example, a correspondence table between the best value (50 μm in the example shown in Figure 9) for the thickness of the fluid film S formed between the sliding upper surface 322 of the bearing movable part 32 and the lower surface 348 of the guide plate 34, and the thickness of the fluid film S formed between the sliding lower surface 323 and the bottom surface 307, and the temperature value of the oil supplied to the hydrostatic hydraulic bearing 3 by the oil recycling unit 36. Note that the best value for the thickness of the fluid film S is not limited to 50 μm, but can be selected between 30 μm and 100 μm. Furthermore, in cases such as when the vibration test stand 50, which has reached a temperature exceeding a predetermined threshold within the environmental test apparatus 19, transfers heat to the multiple hydrostatic hydraulic bearings 3 via the insulating cell structure 4 and the slip table 12, or when there is a change in the weight of the test specimen 195, the oil temperature control unit 368 shown in Figure 5 sends a control signal to the oil recycling unit 36 ​​to correct the temperature of the oil supplied from the oil recycling unit 36 ​​to the hydrostatic hydraulic bearings 3, thereby maintaining the thickness of the fluid film S formed by the hydrostatic hydraulic bearings 3 at the optimal value. In addition to correcting the oil temperature, temperature correction of the temperature-controlled fluid L supplied to the insulating cell structure 4 may also be performed.

[0079] While embodiments of the vibration generating device according to the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. This novel embodiment can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. This embodiment and its variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0080] 1: Vibration generator 12: Slip table 120: Connecting part 124: Counterbore hole 14: Vibration generating part 16: Yoke 18: Joint 19: Environmental testing equipment 190: Equipment housing 193: Sealing component 195: Test specimen 20: Base 3: Hydrostatic hydraulic bearings 30: Bearing body 300: Recess 301: Land 302: Pocket 32: Bearing movable part 321: Connecting surface 323: Sliding lower surface 34: Guide plate 344: Nozzle 36: Oil recycling unit 368: Oil temperature control unit 39: Casing 4: First example of a thermal insulation cell structure 41: Side wall 411: Temperature control fluid inlet 412: Temperature control fluid outlet 42: Connecting wall 43: Cell 44: Cell column 49: Temperature-controlled fluid supply source 499: Temperature-controlled fluid temperature control unit 4A: Second example of an insulating cell structure 4B: Third example of an insulating cell structure 468: Insulating material 4C: Fourth example of a thermally insulated cell structure 461: Outlet 50: Vibration test stand 509: Temperature sensor 60: Displacement sensor

Claims

1. A vibration generating unit that generates vibrations, A plate-shaped slip table that vibrates and is connected to the vibration generating unit, The slip table is supported from below by a plurality of bearings that allow the slip table to vibrate, A vibration test stand housed within an environmental testing apparatus and having a mounting surface on which the test specimen can be fixed, A vibration generating device comprising a heat insulating cell structure having a plurality of hollow cells, disposed between the upper surface of the slip table and the lower surface of the vibration test stand, integrally connected to the slip table and the vibration test stand.

2. The vibration generating device according to claim 1, wherein the bearing is a hydrostatic hydraulic bearing.

3. The vibration generating device according to claim 1, further comprising a thermal insulation material filled inside the cell of the thermal insulation cell structure.

4. The side wall of the cell in the aforementioned heat-insulating cell structure is formed with a temperature-controlled fluid inlet for introducing a temperature-controlled fluid into the cell and a temperature-controlled fluid outlet for releasing the temperature-controlled fluid from the cell. The vibration generating device according to claim 1, further comprising a temperature-controlled fluid supply source that supplies the temperature-controlled fluid into the cell from the temperature-controlled fluid inlet.

5. The aforementioned heat-insulating cell structure comprises a plurality of cell rows in which a plurality of the aforementioned cells are arranged side by side. The vibration generating device according to claim 4, wherein the temperature-controlled fluid supply source supplies the temperature-controlled fluid to the temperature-controlled fluid inlet such that the direction of flow of the temperature-controlled fluid from the temperature-controlled fluid inlet to the temperature-controlled fluid outlet in one of the cell rows is opposite to the direction of flow of the temperature-controlled fluid from the temperature-controlled fluid inlet to the temperature-controlled fluid outlet in another cell row located adjacent to the one cell row.

6. The vibration generating device according to claim 5, wherein the temperature-controlled fluid outlet and the temperature-controlled fluid inlet are offset from each other and formed on the side walls in the direction in which the cells forming the cell row are arranged, so as not to face each other.

7. The vibration generating device according to claim 4, 5, or 6, further comprising a temperature-controlled fluid temperature control unit that adjusts the temperature of the temperature-controlled fluid supplied by the temperature-controlled fluid supply source to the inside of the cell.

8. The hydrostatic hydraulic bearing comprises a bearing body having a recess opening toward the slip table, and a bearing movable part having a connecting surface disposed in the recess of the bearing body and connected to the lower surface of the slip table, and a sliding lower surface that forms a fluid film between itself and the bottom surface of the recess. The vibration generating device according to claim 2, further comprising a displacement sensor for measuring the displacement of the fluid film in the thickness direction relative to the bottom surface of the recess of the sliding lower surface.

Images