Vibration control device and leveling method thereof

Abstract

In a vibration control device that uses both an air spring and a spring member made of metal or resin, the device is designed to flexibly respond to varying degrees of support load. [Solution] The vibration control device 1 includes a movable member 2 on which an external device 1000 as a support is mounted and which is displaced vertically by receiving a load from the external device 1000; an air spring 5 connected to the movable member 2 and elastically supporting a part of the load; a metal or resin spring member 6 connected to the movable member 2 in parallel with the air spring 5 and elastically supporting the other part of the load; and a fixed member 3 installed on the installation surface F as a base and supporting the air spring 5 and the spring member 6. The fixed member 3 is equipped with a leveling mechanism 4 that adjusts the amount of deflection of the spring member 6 in the vertical direction among the air spring 5 and the spring member 6.

Description

Technical Field

[0001] The present disclosure relates to a vibration control device and a leveling method thereof.

Background Art

[0002] Patent Document 1 discloses, as an example of a vibration control device, a pneumatic spring type vibration isolator that combines an air spring and a coil spring. This vibration isolator is configured to support a part of the load by a coil spring in order to cope with an increase in the support load.

[0003] Further, the vibration isolator according to Patent Document 1 includes a well-known leveling valve, and maintains the support height substantially constant by supplying and discharging air to and from the air chamber through a passage (not shown).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in the case of a vibration control device that combines an air spring and a spring member made of metal or resin such as a coil spring as in Patent Document 1, adjustment of the support height needs to be performed through control of the internal pressure of the air chamber. On the other hand, when the configuration disclosed in the same document is adopted, the load support capacity of the spring member cannot be changed from the time of shipment.

[0006] Therefore, when the spring member supports most of the load, the internal pressure of the air chamber becomes very small, which is inconvenient for securing the adjustment cost. In this case, there is a possibility that the internal pressure control of the air chamber becomes unstable.

[0007] On the other hand, if the spring member supports only a small load, the remaining load must be supported by the air spring. In this case, depending on the magnitude of the load borne by the air spring, the internal pressure of the air chamber may be insufficient.

[0008] This disclosure has been made in view of the above, and its purpose is to enable a vibration control device using both an air spring and a spring member to flexibly respond to varying magnitudes of support loads. [Means for solving the problem]

[0009] A first aspect of the present disclosure relates to a vibration control device for elastically supporting a support with respect to a foundation. The vibration control device comprises a movable member on which the support is mounted and which is displaced vertically by receiving a load from the support; an air spring connected to the movable member and elastically supporting a portion of the load; a metal or resin spring member connected to the movable member in parallel with the air spring and elastically supporting the other portion of the load; and a fixed member installed on the foundation and supporting the air spring and the spring member, wherein the fixed member is provided with an adjustment mechanism for adjusting the amount of deflection of the spring member in the vertical direction among the air spring and the spring member.

[0010] In this context, the term "deflection" refers to the amount of expansion or contraction from the natural length.

[0011] According to the first embodiment described above, the vibration control device supports the load from the supported object by sharing the load between an air spring and a spring member. Here, by making the amount of deflection of the spring member adjustable by an adjustment mechanism, the support load of the air spring can be kept within an appropriate range even if the load received from the supported object changes. This allows for flexible adaptation to the magnitude of the support load.

[0012] Furthermore, in general, attempts are made to increase the rigidity and eigenvalue of spring members for purposes such as precise control of the vertical position of movable members. In this case, it is conceivable to increase the spring constant of the spring member and make its deflection amount minute. However, considering the cumulative tolerances of various parts, it is not easy to adjust the deflection amount to a minute and appropriate amount.

[0013] In contrast, according to the first embodiment, it becomes possible to appropriately adjust minute amounts of deflection. This suppresses the cumulative effect of tolerances of various parts and allows for higher eigenvalues ​​of the spring members. Higher eigenvalues ​​of the spring members are advantageous in improving the vibration damping performance of the vibration control device.

[0014] Furthermore, according to a second aspect of the present disclosure, the spring member may be housed in the air chamber of the air spring and press against the ceiling surface of the air chamber, and the vibration control device may further include a sliding part that is supported from below by the adjustment mechanism and slides vertically in accordance with the operation of the adjustment mechanism, the sliding part having a pressing surface that forms the inner bottom surface of the air chamber and faces upward, and an insertion hole that opens to the pressing surface and into which the lower end of the spring member is inserted.

[0015] According to the second embodiment, the lower end of the spring member is retracted into an indentation hole that opens into the pressing surface of the air chamber. Combined with the fact that the spring member is housed in the air chamber, this is advantageous for making the vibration control device more compact.

[0016] Furthermore, according to a third aspect of the present disclosure, the air chamber may contain a damping member that dampens the displacement of the movable member relative to the fixed member, and the damping member may be sandwiched between the ceiling surface and the pressing surface so as to increase or decrease in the amount of deflection.

[0017] According to the third embodiment described above, the damping member is arranged to expand and contract in response to changes in the amount of deflection of the spring member. By expanding and contracting the damping member, its damping performance can be changed. This allows the damping performance to be set to suit the amount of deflection of the spring member.

[0018] Furthermore, according to a fourth aspect of this disclosure, the damping member may have a communication hole that communicates with the recessed hole and into which the upper end of the spring member is inserted, and the damping member may be positioned with respect to the ceiling surface or the inner bottom surface.

[0019] According to the fourth embodiment, the communication hole of the damping member is positioned relative to the ceiling or inner bottom surface of the air chamber. Therefore, the upper end of the spring member inserted into the communication hole is also positioned relative to the ceiling or inner bottom surface of the air chamber. This allows for precise positioning of the spring member.

[0020] Furthermore, a fifth aspect of this disclosure relates to a leveling method for the vibration control device. In this leveling method, an actuator for controlling the internal pressure of the air spring is connected to the air spring. The leveling method may involve mounting the support to the vibration control device while the internal pressure of the air spring is not adjusted, the actuator adjusting the internal pressure of the air spring, and after the internal pressure of the air spring has been adjusted, the adjustment mechanism adjusting the amount of deflection to adjust the height position of the movable member within a range that allows for displacement of the movable member relative to the foundation or the fixed member.

[0021] According to the fifth embodiment described above, the internal pressure of the air spring is adjusted before the amount of deflection is adjusted. This allows the internal pressure of the air spring to be adjusted preferentially, thereby setting the internal pressure within an appropriate range. As a result, even if the load received from the supported object changes, the support load of the air spring can be kept within an appropriate range. [Effects of the Invention]

[0022] As described above, according to the present disclosure, in a vibration control device that uses an air spring and a spring member in combination, it is possible to flexibly respond to the magnitude of the support load.

Brief Description of the Drawings

[0023] [Figure 1] FIG. 1 is a schematic diagram illustrating a vibration control system. [Figure 2] FIG. 2 is a longitudinal sectional view illustrating a vibration control device. [Figure 3] FIG. 3 is a diagram schematically illustrating the configuration of a vibration control device. [Figure 4] FIG. 4 is a block diagram illustrating the configuration related to the control of a vibration control device. [Figure 5] FIG. 5 is a diagram illustrating the leveling procedure of a vibration control device.

Modes for Carrying Out the Invention

[0024] Hereinafter, embodiments of the present disclosure will be described based on the drawings. Note that the following description is illustrative.

[0025] <1. System Configuration> FIG. 1 is a schematic diagram illustrating a vibration control system S, FIG. 2 is a longitudinal sectional view illustrating a vibration control device 1 of the system S, and FIG. 3 is a diagram schematically illustrating the configuration of the vibration control device 1.

[0026] As shown in FIG. 1, the vibration control system S includes one or more (two in the illustrated example) vibration control devices 1 installed on an installation surface F as a foundation, and a controller 100 that controls the vibration control devices 1.

[0027] Here, the installation surface F extends along the horizontal direction. The installation surface F is not limited to a horizontal plane as illustrated in FIG. 1. The installation surface F can be replaced with a general foundation that can support the vibration control device 1 from below.

[0028] Hereinafter, the two horizontal directions extending along the installation surface F and perpendicular to each other will be referred to as the x-direction and the y-direction, respectively, and the vertical direction perpendicular to the installation surface F will be referred to as the z-direction. The x-direction and y-direction may also be collectively referred to as the "xy-direction" or "horizontal direction," and the z-direction may be referred to as the "up-down direction."

[0029] Furthermore, the direction perpendicular to the central axis Oz along the expansion and contraction direction (z-direction) of the air spring 5 and spring member 6 described later is referred to as the "radial direction," and the side approaching the central axis Oz along that radial direction is called the "inner circumference side," while the other side moving away from the central axis Oz is called the "outer circumference side."

[0030] The vibration control device 1 elastically supports the external equipment 1000 as a support with respect to the mounting surface F. The external equipment 1000 is supported by the vibration control device 1 via a rectangular, thick plate-shaped base plate 10. One or more vibration control devices 1 are arranged on the lower surface of the base plate 10, each supporting the base plate 10 from below, and the external equipment 1000 is placed on the upper surface of the base plate 10.

[0031] The configuration of the surface plate 10 is not limited to the example shown. The surface plate 10 may be a table with multiple legs. In that case, each leg of the surface plate 10 may be supported from below by each vibration control device 1. Alternatively, instead of using the surface plate 10, external equipment 1000 may be directly supported by one or more vibration control devices 1.

[0032] The external device 1000 is a manufacturing apparatus for semiconductors, liquid crystal panels, or LED panels. This external device 1000 has various mounts 1001, such as semiconductor silicon wafers, and a movable stage 1002 that supports them. As the stage 1002 moves, the load transmitted to each vibration control device 1 via the base plate 10 changes.

[0033] <2.Device configuration> As shown in Figures 1 and 2, the vibration control device 1 comprises a fixed member 3 installed on the mounting surface F, a movable member 2 that displaces relative to the fixed member 3, an air spring 5 and a spring member 6 interposed between the movable member 2 and the fixed member 3 and expanding and contracting in the direction of the load (vertical direction) of the external device 1000, and a damping member 7. Note that the damping member 7 is not essential.

[0034] -Movable member 2- The movable member 2 receives a load from the external equipment 1000 and is displaced vertically relative to the fixed member 3. As shown in Figure 2, the movable member 2 has a top plate 21. The movable member 2 only needs to be displaced vertically at least, and in this embodiment, it is displaced both vertically and horizontally.

[0035] The top plate 21 has a plate shape extending in the x and y directions. The top plate 21 corresponds to the upper end and top plate portion of the vibration control device 1. External equipment 1000 is mounted on the top plate 21 via the base plate 10. The vibration control device 1 supports the external equipment 1000 via the top plate 21 and the base plate 10.

[0036] - Fixing member 3 - The fixing member 3 supports both the air spring 5 and the spring member 6 from below. As shown in Figure 2, the fixing member 3 has a base plate 31, a support column 32, a guide portion 33, a sliding portion 34, and a clamping member 35. The sliding portion 34 may be considered as an element of the air spring 5 or the spring member 6.

[0037] The base plate 31 has a plate shape extending in the x and y directions. A leveling mechanism 4 and a support column 32 are arranged on the upper surface of the base plate 31. The leveling mechanism 4 is an example of an "adjustment mechanism" in this embodiment.

[0038] Of these, the leveling mechanism 4 is located inside the support column 32 in the radial direction. The leveling mechanism 4 is also located between the base plate 31 and the slide portion 34 in the vertical direction.

[0039] More specifically, the leveling mechanism 4 is located in the center of the upper surface of the base plate 31. Specifically, a first positioning portion 31a is located in the center of the upper surface of the base plate 31. This first positioning portion 31a is composed of a recess that is indented downward from the upper surface of the base plate 31. By fitting the lower mold 44 of the leveling mechanism 4 into the first positioning portion 31a, the leveling mechanism 4 is positioned in the x and y directions.

[0040] More specifically, the leveling mechanism 4 has a thick plate shape in which the dimension in the z direction is smaller than the dimension in the x and y directions, as shown in Figure 2. This leveling mechanism 4 includes an adjustment screw 41 accessible from one side in the x direction, a wedge-shaped medium 42 that moves in the x direction in conjunction with the operation of the adjustment screw 41, and an upper dies 43 and a lower dies 44 that clamp the medium dies 42 from both the upper and lower sides.

[0041] The leveling mechanism 4 can move the middle mold 42 via the adjustment screw 41, thereby moving the upper mold 43 and the lower mold 44 closer together and further apart in the vertical direction. As a result of this movement, the upper surface of the leveling mechanism 4 can be moved vertically relative to the base plate 31.

[0042] Furthermore, a sliding part 34 is mounted on the upper surface of the leveling mechanism 4. By moving the upper surface of the leveling mechanism 4 in the vertical direction, the sliding part 34 mounted on that upper surface can be moved in the vertical direction.

[0043] The support columns 32 are positioned radially outward relative to the leveling mechanism 4. Multiple support columns 32 are arranged at equal intervals in the circumferential direction around the central axis Oz. Each support column 32 supports the guide portion 33 from below.

[0044] The guide portion 33 has a cylindrical shape that extends in the vertical direction. The guide portion 33 includes a cylindrical portion 33a that extends in the vertical direction and a flange portion 33b that extends radially outward from the lower end of the cylindrical portion 33a and is supported from below by the support column portion 32.

[0045] The cylindrical portion 33a has a through hole extending in the vertical direction, which guides the vertical sliding of the slide portion 34. In detail, the lower end of the cylindrical portion 33a protrudes slightly inward in the radial direction. The protruding portion 33c formed by this lower end faces the outer circumferential surface of the slide portion 34 with a small clearance between them. This guides the sliding of the slide portion 34 relative to the cylindrical portion 33a.

[0046] The sliding portion 34 has a columnar shape that extends in the vertical direction. The sliding portion 34 is supported from below by the leveling mechanism 4. The sliding portion 34 slides vertically as the leveling mechanism 4 operates.

[0047] A second positioning portion 34a for positioning the leveling mechanism 4 in the XY direction is located on the lower surface of the slide portion 34. This second positioning portion 34a is formed on the lower surface of the slide portion 34 and consists of a recess that is recessed upward. By fitting the upper mold 43 of the leveling mechanism 4 into the second positioning portion 34a, the leveling mechanism 4 is positioned in the xy direction.

[0048] Thus, the leveling mechanism 4 is positioned inside the support column 32 in the radial direction, and between the base plate 31 and the slide portion 34 in the vertical direction.

[0049] The upper surface of the sliding portion 34 has a recess 51 that is indented downwards. This recess 51 forms the air chamber Sp that expands and contracts vertically in the air spring 5, and in particular the side wall and inner bottom surface of the air chamber Sp.

[0050] The bottom surface (pressing surface 34b) of the recess 51 forms the inner bottom surface of the air chamber Sp. This pressing surface 34b faces upward and is opposite the ceiling surface of the air chamber Sp. This pressing surface 34b is provided with an insertion hole 34c into which the lower end of the spring member 6 is inserted.

[0051] Here, the immersion hole 34c extends in the vertical direction and opens onto the pressing surface 34b. The dimensions of the immersion hole 34c in the vertical direction are set according to the specifications of the spring member 6. The immersion hole 34c can also be used to position the spring member 6 in the x and y directions.

[0052] Furthermore, a roughly ring-shaped clamping member 35 is placed on the upper end of the slide portion 34. This clamping member 35, together with the upper end of the slide portion 34, clamps the outer edge of the diaphragm 53 (described later) from above and below.

[0053] -Air spring 5- The air spring 5 is connected to the top plate 21, which is a movable member 2. The air spring 5 is configured to elastically support a portion of the load from the external equipment 1000.

[0054] The air spring 5 has a case with an opening at its upper end (in this embodiment, a recess 51 in the slide portion 34), and a piston 52 that is airtightly inserted into the upper end opening via a diaphragm 53, and together with the diaphragm 53 and the recess 51, partitions the air chamber Sp.

[0055] The air spring 5 is connected to the top plate 21 via a piston 52, and also connected to the base plate 31 via a recess 51 and a leveling mechanism 4.

[0056] The piston 52 according to this embodiment has a substantially T-shape in cross-sectional view as shown in Figure 2. The piston 52 includes, in order from top to bottom, a first piston portion 52a, a second piston portion 52b, and a third piston portion 52c.

[0057] The first piston portion 52a is fixed to the center of the lower surface of the top plate 21 and constitutes the horizontal side of the T-shape. The first piston portion 52a has a plate shape in which the dimensions in the x and y directions are smaller than those of the top plate 21, and the dimensions in the z direction are smaller than those in the x and y directions.

[0058] The second piston portion 52b is fitted into the center of the lower surface of the first piston portion 52a and protrudes downward from the center. The second piston portion 52b has a substantially cylindrical shape, with smaller dimensions in the x and y directions and larger dimensions in the z direction than the first piston portion 52a.

[0059] The third piston portion 52c is inserted and fastened through the lower opening of the second piston portion 52b, and has a lid shape that closes the opening. The radially outer upper surface of the third piston portion 52c, together with the lower surface of the second piston portion 52b, sandwiches the inner periphery of the diaphragm 53 from above and below. Furthermore, the lower surface of the third piston portion 52c forms the ceiling surface of the air chamber Sp, as shown in Figure 2.

[0060] The diaphragm 53 is made of, for example, a rubber material, has a thin thickness in the z direction, and is formed in an annular shape that extends in the x and y directions. More specifically, the diaphragm 53 can be made of, for example, a rubber elastic membrane with a polyester fiber fabric embedded as a reinforcing material.

[0061] As described above, both the inner and outer peripheral edges of the diaphragm 53 are held by the sliding portion 34, the clamping member 35, the second piston portion 52b, and the third piston portion 52c. In detail, the diaphragm 53 is held in a state of bending in the x and y directions to allow displacement of the top plate 21 and piston 52 relative to the base plate 31, the leveling mechanism 4, and the sliding portion 34.

[0062] By clamping both peripheral edges of the diaphragm 53, an air chamber Sp is partitioned inside the vibration control device 1. This air chamber Sp has side walls and an inner bottom surface formed by the recess 51, a top surface formed by the piston 52, and the gap between the recess 51 and the piston 52 is sealed by the diaphragm 53.

[0063] As the air chamber Sp expands and contracts vertically, the air spring 5 expands and contracts vertically. As the air spring 5 expands and contracts vertically, the top plate 21 is displaced vertically.

[0064] The support load of the air spring 5 is controlled by adjusting the air pressure (internal pressure) in the air chamber Sp. On the other hand, as shown in Figure 2, the air spring 5 is supported from below by the sliding part 34, and expands and contracts in the vertical direction as the sliding part 34 moves.

[0065] However, the support load of the air spring 5 is largely adjusted through the internal pressure. The influence of the sliding portion 34 on the support load of the air spring 5 is relatively small compared to the influence on the spring member 6, which will be described later. Therefore, in the schematic diagram shown in Figure 3, the air spring 5 is positioned away from the sliding portion 34 in order to exaggerate the relationship between the support load of the air spring 5 and the internal pressure. This is also the case in Figure 5, which will be described later.

[0066] -Spring member 6- As illustrated in Figures 2 and 3, the spring member 6 is connected in parallel to the air spring 5 to the top plate 21, which is the movable member 2. The spring member 6 elastically supports the load from the external equipment 1000. The spring member 6 is made of metal or resin. In this embodiment, the spring member 6 is a metal compression coil spring. At the factory shipment stage, that is, before leveling, the spring member 6 is not pre-compressed and is provided in a free length state. The material constituting the spring member 6 may be hard steel wire, stainless steel, piano wire, or various resins.

[0067] The spring member 6 is configured to expand and contract vertically and is housed within the air chamber Sp of the air spring 5. As the spring member 6 expands and contracts vertically, the top plate 21 is displaced vertically.

[0068] More specifically, the spring member 6 has an upper end that contacts the lower surface of the piston 52 and a lower end that is retracted into the retraction hole 34c and presses the slide portion 34 downward.

[0069] The spring member 6 is connected to the top plate 21 via the piston 52 by bringing its upper end into contact with the lower surface of the piston 52 (they are elastically joined). The spring member 6 presses against the ceiling surface of the air chamber Sp via its upper end. Fixing the upper end of the spring member 6 to the top plate 21 is not essential.

[0070] The spring member 6 is also connected to the base plate 31 via the slide portion 34 and the leveling mechanism 4 by pressing the slide portion 34 through its lower end (elastically joined). The air spring 5 and the spring member 6 are installed on the mounting surface F via a common fixing member 3.

[0071] As described above, the leveling mechanism 4 slides the slide portion 34 up and down. When the slide portion 34 moves up and down, the lower end of the spring member 6 moves up and down. This movement adjusts the amount of deflection (amount of expansion and contraction from the natural length) of the spring member 6 in the vertical direction. In this way, the leveling mechanism 4 according to this embodiment adjusts the amount of deflection of the spring member 6 in the vertical direction, among the air spring 5 and the spring member 6. In this embodiment, the restoring force (reaction force) of the spring member 6 increases as it compresses from its natural length (as the amount of deflection increases).

[0072] - Damping member 7 - The damping member 7 dampens the displacement of the movable member 2 relative to the fixed member 3. As shown in Figure 2, the damping member 7 is composed of a first damping member 71 and a second damping member 72.

[0073] The first damping member 71 dampens the displacement of the movable member 2 in the vertical direction. This first damping member 71 is made of, for example, high-damping rubber. The first damping member 71 also has a substantially disc shape that extends in the vertical direction.

[0074] As shown in Figure 2, the first damping member 71 is built into the air chamber Sp. More specifically, the first damping member 71 is sandwiched between the inner bottom surface (pressure surface 34b) of the air chamber Sp and the top surface of the air chamber Sp. As a result, the first damping member 71 is arranged in parallel with the air spring 5 and the spring member 6 (see Figure 3).

[0075] With this arrangement, the first damping member 71 expands and contracts vertically in accordance with the increase or decrease in the amount of deflection of the spring member 6 by the leveling mechanism 4. In this embodiment, when the first damping member 71 contracts, its damping performance increases, and when the first damping member 71 extends, its damping performance decreases.

[0076] The first damping member 71 also has a communication hole 71a that communicates with the recessed hole 34c and into which the upper end of the spring member 6 is inserted. By being recessed and inserted into the recessed hole 34c and the communication hole 71a, the spring member 6 is positioned over substantially its entire vertical range.

[0077] The first damping member 71 is also fitted into a recess provided on the ceiling surface or the pressing surface 34b of the air chamber Sp (pressing surface 34b in the illustrated example). This positions the first damping member 71 relative to the pressing surface 34b of the air chamber Sp.

[0078] The second damping member 72 dampens the displacement of the movable member 2 in the horizontal direction. This second damping member 72 is made of, for example, high-damping rubber. Furthermore, the second damping member 72 has a larger diameter ring shape than the first damping member 71.

[0079] As shown in Figure 2, the second damping member 72 is located outside the air chamber Sp. More specifically, the second damping member 72 is sandwiched between the outer circumferential surface of the first piston portion 52a and the inner circumferential surface of the upper end of the guide portion 33.

[0080] -Actuator 8- Furthermore, an actuator 8 is connected to the air spring 5 to control the internal pressure of the air spring 5 (see Figure 1). This actuator 8 is electrically connected to the controller 100 and operates based on electrical signals from the controller 100. Although not shown in the figures, the actuator 8 may be located inside the housing of each vibration control device 1.

[0081] In detail, each air spring 5 is connected to piping for supplying compressed air from an air pressure source (not shown), and each actuator 8 is composed of a servo valve interposed in the piping. The actuator 8, acting as a servo valve, adjusts the supply and exhaust flow rates of compressed air to the corresponding air spring 5 by changing its opening degree.

[0082] The actuator 8 adjusts the supply flow rate and exhaust flow rate, thereby adjusting the internal pressure of the air spring 5. By controlling the internal pressure of the air spring 5, it is possible to make the air spring 5 exhibit a desired load-supporting capacity or to apply a control force or displacement to the external device 1000 via the base plate 10. In this case, the control force or displacement applied acts in the vertical direction.

[0083] Furthermore, applying a control force or displacement to the external device 1000 (by exciting the external device 1000 via the surface plate 10) is effective in suppressing vibrations of the external device 1000 before or after the event.

[0084] The vibration control device 1 functions as an active-type vibration isolation device configured to perform so-called "active vibration isolation control." Active vibration isolation control blocks the transmission of vibrations from the mounting surface F to the external equipment 1000. As a result, vibrations of the external equipment 1000 caused by vibration transmission from the mounting surface F to the external equipment 1000 are suppressed.

[0085] The vibration control device 1 functions as an active-type vibration damping device configured to perform so-called "active vibration damping control." Through active vibration damping control, vibrations originating from the external equipment 1000 itself (for example, vibrations caused by the movement of the stage 1002) are suppressed.

[0086] It is not mandatory for the vibration control device 1 to be an active type vibration isolation or damping device. By eliminating the internal pressure control based on the detection signal of the state sensor 9, the vibration control device 1 may be a passive type vibration isolation or damping device.

[0087] Furthermore, various controls performed by the actuator 8 are carried out based on the detection signals of each of the multiple state sensors 9. Each state sensor 9 is electrically connected to the controller 100. Each state sensor 9 inputs a detection signal to the controller 100 indicating the vibration state of each vibration control device 1 or the installation surface F.

[0088] Here, the term "vibration state" includes state quantities that characterize the vibration of each vibration control device 1 or the installation surface F, such as acceleration and displacement. In addition, in the following description, the term "feedback" may be simply referred to as "FB," and the term "feedforward" may be simply referred to as "FF."

[0089] The multiple state sensors 9 include a FB acceleration sensor 91. The FB acceleration sensor 91 detects the acceleration of the top plate 21 or the base plate 10 (particularly the acceleration in the z direction).

[0090] The multiple state sensors 9 include FB displacement sensors 92. The FB displacement sensors 92 detect the amount of displacement of the top plate 21 or the base plate 10 relative to the base plate 31 or the mounting surface F (particularly the amount of displacement in the z direction).

[0091] The multiple state sensors 9 include an FF acceleration sensor 93. The FF acceleration sensor 93 detects the acceleration of the base plate 31 or the mounting surface F (particularly the acceleration in the z direction).

[0092] -Other components- Although both the air spring 5 and the spring member 6 are configured to expand and contract in the vertical direction, they may also be configured by combining an air spring 5 and / or a spring member 6 that expands and contracts in the horizontal direction. In that case, a second actuator (e.g., a linear motor) for applying a control force or displacement in the horizontal direction may be further combined, or a second state sensor capable of detecting various vibration states in the horizontal direction may be further combined to control the second actuator.

[0093] When a second actuator and a second state sensor related to the horizontal direction are used, the system may be configured to perform "active vibration isolation control" and "active vibration damping control" related to the horizontal direction, in addition to the "active vibration isolation control" and "active vibration damping control" related to the vertical direction described later.

[0094] <2. Control Configuration> Figure 4 is a block diagram illustrating the configuration for controlling the vibration control device 1. The controller 100 includes a CPU, memory, and an input / output bus. This controller 100 is configured to control the vibration control device 1 via actuators 8 based on detection signals from multiple state sensors 9.

[0095] The following describes in detail the control of the vibration control device 1 via the actuator 8. For convenience, only the control of the vertical actuator 8 will be described, but if an actuator (second actuator) is also provided in the horizontal direction, the same control will be applied to that actuator as well.

[0096] Specifically, the controller 100 includes a vibration isolation FB control unit 100a, a vibration damping FB control unit 100b, a vibration isolation FF control unit 100c, etc., and is configured to input control signals to the actuator 8, thereby applying a control force to the vibration control device 1 to suppress its vibrations.

[0097] As shown in Figure 4, the input to the actuator 8 is mainly composed of a combination of vibration isolation feedback control amount, vibration damping feedback control amount, and vibration isolation feedforward control amount.

[0098] Here, the vibration isolation feedback operation amount is calculated by the vibration isolation FB control unit 100a based on the detection signal of the FB acceleration sensor 91. The vibration damping feedback operation amount is calculated by the vibration damping FB control unit 100b based on the detection signal of the FB displacement sensor 92. The vibration isolation feedforward operation amount is calculated by the vibration isolation FF control unit 100c based on the detection signal of the FF acceleration sensor 93.

[0099] The vibration isolation FB control unit 100a performs vibration isolation FB control. Vibration isolation FB control generates a control force using the air spring 5 to reduce vibration based on the value detected by the FB acceleration sensor 91, i.e., the vertical acceleration of the top plate 21 or the base plate 10. For example, the vibration isolation FB control unit 100a multiplies the detected acceleration value, the derivative value of the detected value, and the integral value of the detected value by a feedback gain, adds them together, inverts the result, and uses it as the control input to the actuator 8.

[0100] The vibration damping FB control unit 100b performs vibration damping FB control. Vibration damping FB control suppresses the tilt of the base plate 10 and / or the vibrations caused by that tilt by controlling the internal pressure of the air spring 5 so that the detected value of the FB displacement sensor 92, i.e., the amount of change in the vertical position of the top plate 21 or base plate 10, is reduced. For example, the vibration damping FB control unit 100b subtracts the detected displacement value from a target value (zero) and then determines the control input to the actuator 8 according to the PID control law.

[0101] The vibration isolation FF control unit 100c performs vibration isolation FF control. Vibration isolation FF control is a process that generates vibrations with the opposite phase to cancel out vibrations transmitted from the FF acceleration sensor 93, i.e., the vibration state of the installation surface F (floor vibration), to the object to be vibration isolated (surface plate 10 or external equipment 1000). The vibration isolation FF control unit 100c can determine the control input to the actuator 8 using, for example, a digital filter. The characteristics of this digital filter are determined by using the transfer function H(s) when the floor vibration is transmitted to the vibration control device 1 via the air spring 5 and the transfer function K(s) of the compensation system formed by the air spring 5, and then -H(s)·K(s) -1 It is expressed as follows.

[0102] Then, upon receiving the control input described above, the actuator 8 is activated, and the internal pressure of each air spring 5 is controlled, thereby applying an appropriate control force to the base plate 10 and the external equipment 1000. In other words, vibrations transmitted from the mounting surface F are suppressed by vibration isolation FF control, and any minute vibrations that are still transmitted are reduced by vibration isolation FB control, resulting in extremely high vibration isolation performance.

[0103] Furthermore, relatively large vibrations, that is, vibrations (shaking) that occur in the top plate 21 due to the operation of external equipment 1000, will be attenuated by combining vibration damping FB control with the aforementioned vibration isolation FB control.

[0104] <3. Leveling Method> Figure 5 is a diagram illustrating the leveling procedure of the vibration control device 1.

[0105] First, as shown in Figure 5(a), the external device 1000 is mounted on the vibration control device 1. This mounting is performed with the internal pressure of the air spring 5 not adjusted (internal pressure adjustment: none). This state corresponds to a state where no air is supplied to the air chamber Sp of the air spring 5, and the top plate 21 is not floating relative to the base plate 31. At this time, the air spring 5 does not have load-bearing capacity, and the spring member 6 is in a free length state.

[0106] Next, as shown in Figure 5(b), the actuator 8 illustrated in Figure 1 adjusts the internal pressure of the air spring 5 (internal pressure adjustment: present). The internal pressure of the air spring 5 is adjusted to a range suitable for internal pressure control by the actuator 8 after leveling. Furthermore, although the internal pressure adjustment is performed in a direction that increases the support load of the air spring 5, it is performed within a range that is below the load from the external equipment 1000. As a result, the top plate 21 is still not floating relative to the base plate 31, and the distance between the two plates 21 and 31 is maintained at "H0" as in (a) above.

[0107] Next, as shown in Figure 5(c), the leveling mechanism 4 adjusts the amount of deflection of the spring member 6. This adjusts the height position of the movable member 2 within the range that allows for displacement (stroke) of the movable member 2 relative to the installation surface F or the fixed member 3. This adjustment is performed after adjusting the internal pressure of the air spring 5 (internal pressure adjustment: present).

[0108] In detail, the amount of deflection of the spring member 6 is adjusted in a direction that increases its support load (see "H1" in Figure 5). As the amount of deflection of the spring member 6 increases, the damping performance of the damping member 7, particularly the first damping member 71, also increases. By adjusting the amount of deflection, the sum of the support load of the air spring 5 and the support load of the spring member 6 reaches the load received from the external equipment 1000. As a result, the top plate 21 floats above the base plate 31 (see "H2" in Figure 5). Leveling of the vibration control device 1 is completed by adjusting the displacement (stroke) of the top plate 21 relative to the base plate 31.

[0109] <4. Significance of this embodiment> As described above, the vibration control device 1 according to this embodiment supports the load from the external device 1000 by sharing the load between the air spring 5 and the spring member 6, as shown in Figure 3. Here, by making the amount of deflection of the spring member 6 adjustable by the leveling mechanism 4, even if the load received from the external device 1000 changes, the support load of the air spring 5 can be kept within an appropriate range. This allows for flexible response to changes in the magnitude of the support load.

[0110] Furthermore, attempts are generally made to increase the rigidity and eigenvalue of the spring member 6 in order to precisely control the vertical position of the movable member 2. In this case, it is conceivable to increase the spring constant of the spring member 6 and make its deflection amount minute. However, considering the cumulative tolerances of various parts, it is not easy to adjust the deflection amount to a minute and appropriate amount.

[0111] In contrast, according to the above embodiment, even if the amount of deflection is minute, it is possible to adjust it appropriately by the leveling mechanism 4 illustrated in Figures 2 and 3. This suppresses the cumulative effect of tolerances of various parts and makes it possible to increase the eigenvalue of the spring member 6. Increasing the eigenvalue of the spring member 6 is beneficial in improving the vibration damping performance of the vibration control device 1.

[0112] Furthermore, as shown in Figure 2, the lower end of the spring member 6 is retracted into the retraction hole 34c that opens into the pressing surface 34b of the air chamber Sp. Combined with the fact that the spring member 6 is built into the air chamber Sp, this is advantageous for making the vibration control device 1 more compact.

[0113] Furthermore, as shown in Figure 2, the first damping member 71 is arranged to expand and contract in response to changes in the amount of deflection of the spring member 6. By expanding and contracting the first damping member 71, its damping performance can be changed. This allows the damping performance to be set to suit the amount of deflection of the spring member 6.

[0114] Furthermore, as shown in Figure 2, the communication hole 71a of the first damping member 71 is positioned relative to the pressing surface 34b of the air chamber Sp. Therefore, the upper end of the spring member 6 inserted into the communication hole 71a is also positioned relative to the pressing surface 34b of the air chamber Sp. This allows for precise positioning of the spring member 6.

[0115] Furthermore, as explained using Figure 5, the internal pressure of the air spring 5 is adjusted before the amount of deflection is adjusted. This allows the internal pressure of the air spring 5 to be adjusted preferentially, thereby setting the internal pressure within an appropriate range (for example, within a range where internal pressure control is stable). As a result, even if the load received from the external device 1000 as the supported object changes, the support load of the air spring 5 can be kept within an appropriate range.

[0116] Furthermore, the vibration control device 1 according to this embodiment can contribute to achieving Goal 9, "Build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation," which is one of the Sustainable Development Goals (SDGs), an international goal aimed at creating a sustainable and better world by 2030, as outlined in the "2030 Agenda for Sustainable Development," which was unanimously adopted by member states at the UN Summit in September 2015.

[0117] <5. Other Embodiments> In the above embodiment, a vibration control device 1 functioning as an active type vibration isolation device was exemplified, but it is not essential that the vibration control device 1 function as a vibration isolation device. The vibration control device 1 only needs to function as a vibration damping device at the very least.

[0118] Furthermore, while the above embodiment exemplified a leveling mechanism 4 having a wedge-shaped medium 42 as an adjustment mechanism, the adjustment mechanism according to this disclosure is not limited to such a leveling mechanism 4.

[0119] For example, the adjustment mechanism may be a spring-type mount positioned to support the slide portion 34 from below. In this case, each mount may be height-adjusted by screwing in various fastening members such as so-called leveling bolts, or by operating an electric component such as a linear motor. [Explanation of symbols]

[0120] S Vibration Control System 1. Vibration control device 2 Movable members 3 Fixing member 34. Slide section 34b Pressing surface 34c immersion hole 4. Leveling mechanism (adjustment mechanism) 5. Air spring 51 Recess 52 pistons 53 Diaphragm 6 Spring member 7 Damping member 71 First damping member (damping member) 71a Communication hole 72 Second damping member 8 Actuators 9. State Sensor 10 Surface plate 100 controllers 1000 External equipment (supported body) F Installation surface (foundation) sp air chamber

Claims

1. A vibration control device that elastically supports a support with respect to a foundation, A movable member on which the support is mounted and which is displaced vertically by receiving a load from the support, An air spring connected to the movable member and elastically supporting a portion of the load, A spring member made of metal or resin is connected to the movable member in parallel with the air spring and elastically supports the other part of the load, The system includes a fixing member installed on the aforementioned foundation and supporting the air spring and the spring member, The fixing member is provided with an adjustment mechanism for adjusting the amount of deflection of the spring member in the vertical direction, among the air spring and the spring member. A vibration control device characterized by the following features.

2. In the vibration control device described in claim 1, The spring member is housed in the air chamber of the air spring and presses against the ceiling surface of the air chamber. The device further comprises a sliding part that is supported from below by the adjustment mechanism and slides vertically in accordance with the operation of the adjustment mechanism, The aforementioned sliding portion is The pressing surface that forms the inner bottom surface of the air chamber and faces upward, The pressing surface has an opening and an insertion hole into which the lower end of the spring member is inserted, A vibration control device characterized by the following features.

3. In the vibration control device described in claim 2, The air chamber contains a damping member that dampens the displacement of the movable member relative to the fixed member. The damping member is held between the ceiling surface and the pressing surface so as to expand and contract in accordance with the increase or decrease in the amount of deflection. A vibration control device characterized by the following features.

4. In the vibration control device described in claim 3, The damping member has a communication hole that communicates with the recessed hole and into which the upper end of the spring member is inserted. The damping member is positioned with respect to the ceiling surface or the inner bottom surface. A vibration control device characterized by the following features.

5. A leveling method for a vibration control device according to any one of claims 1 to 4, An actuator is connected to the aforementioned air spring to control the internal pressure of the air spring. With the internal pressure of the air spring not adjusted, the support is mounted on the vibration control device. The actuator adjusts the internal pressure of the air spring. After the internal pressure of the air spring is adjusted, the adjustment mechanism adjusts the amount of deflection to set the height position of the movable member within a range that allows for displacement of the movable member relative to the foundation or the fixed member. A leveling method for a vibration control device, characterized by the features described above.

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