JP4469093B2 - Vibration isolator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a structure of a vibration isolation device that blocks external vibrations, and more particularly to a vibration isolation device that is suitable when a small device or component is to be installed.
[0002]
[Prior art]
Conventionally, when fixing a device or component that is extremely disliked by vibration, a vibration isolator is used to prevent the vibration from adversely affecting this type of device or component.
[0003]
The vibration isolator is largely divided into a passive vibration isolator that absorbs small vibrations via an elastic support means such as an air spring and an active vibration isolator that forcibly suppresses vibrations using a hydraulic actuator or the like. Divided. In some cases, a passive type vibration isolator has insufficient vibration isolation capability for large vibrations, and recently, an active type vibration isolation device with more excellent vibration isolation capability has been frequently used.
[0004]
[Problems to be solved by the invention]
However, the active vibration isolator using a conventional hydraulic actuator has a problem that it requires installation of a pump, a valve, etc., and takes up a place, and further, the quick response to high frequency vibration is not sufficient. .
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vibration isolation device that can be reduced in size and has excellent quick response.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1, for example, as shown in FIGS. 1 to 4, mounts a vibration isolation object directly or indirectly on the vibration isolation table 4, and applies external vibration. An anti-vibration device 100 for isolating vibrations so as not to be transmitted to the anti-vibration target, the actuator 5 for driving the anti-vibration table, vibration detection means (acceleration sensor 12) for detecting vibration of the anti-vibration table, Control means (control device 13) for controlling the actuator to suppress the vibration of the vibration isolation table by feeding back the output of the vibration detection means, and the actuator is in a gap in which a magnetic field is formed. An electromagnetic force is generated by supplying an electric current to the coil unit (coil 52) to be stored to drive the coil unit in the vertical direction to drive the vibration isolation table connected to the coil unit. , Excluding Upper leaf spring fixing members 81 are installed on both left and right ends of the base 4, and lower leaf spring fixing members 82 are installed on both left and right ends of the base 6. The upper leaf spring fixing member 81 includes an upper leaf spring. One end of 91 is fixed, one end of a lower plate spring 92 is fixed to the lower plate spring fixing member 82, and the other ends of the upper plate spring 91 and the lower plate spring 92 are directed outward of the base 6. An upper plate spring 91 that protrudes and is fixed to a plate spring fixing plate 83 spaced from the vibration isolation table 4 and the base 6, and is fixed to the vibration isolation table 4 by the upper plate spring fixing member 81, and the lower plate The anti-vibration table 4 is elastically supported above the base 6 by the lower plate spring 92 fixed to the base 6 by a spring fixing member 82 flexing up and down according to the vertical vibration of the base 6. It is characterized by being.
[0006]
According to the first aspect of the present invention, when the vibration isolator provided with the vibration isolation table is slightly displaced by external vibration, the vibration detection means installed on the vibration isolation table detects the vibration of the vibration isolation table, In response, the control means controls the actuator so as to suppress the vibration of the vibration isolation table. More specifically, since a magnetic field is formed in the gap of the actuator, an electromagnetic force is generated in the gap when a predetermined current is supplied from the control means to the coil portion accommodated in the gap. The unit is driven in the vertical direction. By controlling this driving force to be about the same as the external vibration and in the opposite direction, the actuator drives the vibration isolation table in the opposite direction to the vibration direction. The position of the vibration isolation table can be kept constant.
Therefore, since the actuator is operated by current control, there is no need for a pump or a valve as in the case of a hydraulic actuator, and it is possible to provide a vibration isolation device that is easier to reduce in size and more excellent in quick response.
Here, as the vibration detection means, for example, an accelerometer, a speedometer, a displacement meter, or the like is used.
As a means for generating a magnetic field, for example, a permanent magnet or an electromagnet is used.
[0008]
In particular , when the vibration from the outside extends not only in the vertical direction but also in the horizontal direction, the leaf spring acts as an original spring system by bending the leaf spring to the force in the vertical direction. In order to suppress the vibration, the vibration isolation table is elastically supported on the base of the vibration isolation device by using a leaf spring, so that only the vibration in the vertical direction capable of vibration isolation can be transmitted to the vibration isolation table. Therefore, it is sufficient for the vibration isolator to eliminate the influence of only the vibration in the vertical direction, and more reliable vibration isolation can be performed.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 is a front view of a vibration isolator 100 according to the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is a cross-sectional view taken along line AA of FIG. FIG. 4 is a block diagram showing the configuration of the present invention.
[0010]
First, the structure of the vibration isolation device 100 will be described. The vibration isolator 100 mainly includes a vibration isolation object mounting stage 1, a bridge 2 for mounting the vibration isolation object mounting stage 1, a detector mounting base 3, a vibration isolation base 4, an actuator 5, a base 6, and a stopper. 7, an acceleration sensor 12, a control device 13, an amplifier 14 and the like, and are fixed to the upper surface of the base 10 connected to the ground.
The size of the vibration isolator 100 is, for example, about 95 mm in width and depth, and about 70 mm in height.
[0011]
A vibration isolation object mounting stage 1 for mounting a vibration isolation object is installed on a bridge 2 that is a portal shape, and is fixed to the bridge 2 with a nut 11. The bridge 2 is fixed to the upper surface of the detector mounting base 3 and both ends before and after the drawing in FIG. 1. The detector mounting base 3 is, for example, a plate-like body having a substantially square shape in plan view. Four sides are fixed to the upper surface with a nut 31. An acceleration sensor 12 that detects vibration is attached to the detector mount 3. The vibration isolation table 4 is, for example, a plate-like body having a substantially square shape in plan view, and is connected to the actuator 5 via drive shafts 53 provided in four directions. In the center of both ends of the vibration isolation table 4 before and after the drawing in FIG. 1, a terminal block 41 is arranged so that the lower part is sandwiched between the vibration isolation table 4 and the detector mounting base 3. Fixed to the base 4. A plurality of pins 41a... Are arranged in parallel on both sides of the upper portion of the terminal block 41, and the acceleration sensor 12 is connected to the pins 41a.
[0012]
The lower part of the actuator 5 is embedded in the base 6 and fixed by a nut 56, and the vibration isolation table 4 is elastically disposed above the base 6 via an upper leaf spring 91 and a lower leaf spring 92. It is supported.
The base 6 is, for example, a plate-like body having a substantially square shape in a plan view. An inverted L-shaped stopper 7 is fixed to the left and right sides of the drawing in FIG. It extends to.
[0013]
A U-shaped terminal block 62 is disposed on the upper surface of the base 6 and in the center of the end portions before and after the drawing in FIG. 1, and is fixed to the base 6 with a nut 63. The terminal block 62 has substantially the same height as the vibration isolation table 4, and a plurality of protruding pins are arranged in parallel in the vertical direction on the upper horizontal surface.
[0014]
The stopper 7 is provided to limit the upward displacement of the vibration isolation table 4 elastically supported by the upper leaf spring 91 and the lower leaf spring 92. When the vibration transmitted from the outside exceeds a certain level Further, an upper leaf spring fixing member 81 (described later) comes into contact with the stopper 7.
[0015]
Next, the support structure of the vibration isolation table 4 by the base 6 will be described in detail.
In the base 6 and the vibration isolation table 4, an upper leaf spring fixing member 81 and a lower leaf spring fixing member 82 are installed at both left and right ends of the drawing in FIG. The upper leaf spring fixing member 81 and the lower leaf spring fixing member 82 are long plate-like bodies having a length slightly shorter than one side of the base 6, and along the side edges of the base 6 and the vibration isolation table 4. Has been placed. One end of two upper and lower upper plate springs 91 and 92 which are parallel to each other are fixed to both ends of the upper plate spring fixing member 81 and the lower plate spring fixing member 82. The other ends of the upper plate spring 91 and the lower plate spring 92 protrude outward from the base 6 and are fixed to the plate spring fixing plate 83.
[0016]
The plate spring fixing plate 83 is a long plate-like body having the same width as the upper plate spring fixing member 81 and the lower plate spring fixing member 82, and the height is slightly lower than the stopper 7. The plate spring fixing plate 83 is configured to fix four plate springs (two upper plate springs 91 and two lower plate springs 92) parallel to each other in the longitudinal direction at both ends.
[0017]
As described above, the upper leaf spring 91 fixed to the vibration isolation table 4 by the upper leaf spring fixing member 81 and the lower leaf spring 92 fixed to the base 6 by the lower leaf spring fixing member 82 are respectively the leaf spring fixing plates 83. And is bent up and down according to the vertical vibration of the base 6. Therefore, when external vibration is transmitted from the base 10 to the base 6, the upper leaf spring 91 and the lower leaf spring 92 are bent, so that the vibration isolation table 4 is elastically supported above the base 6.
[0018]
The actuator 5 is a motor that performs linear motion such as a voice coil motor, and includes a magnet 51, a coil bobbin (not shown), a coil 52, a drive shaft 53, a leaf spring 54, a terminal block 55, and the like.
[0019]
The magnet 51 is a substantially cubic permanent magnet fixed to the base 6 with a nut 56 and provided with cylindrical grooves on four sides thereof, and a magnetic field is formed in the cylindrical groove. One coil 52 that is a wire wound around a coil bobbin is housed one by one in the upper part of the cylindrical groove. The upper part of the coil bobbin is connected to the lower part of the drive shaft 53, and the lower part of the coil 52 is supported by a leaf spring 54. Further, both ends of the coil 52 are connected to pins provided on the terminal block 55.
When the actuator 5 configured as described above supplies a predetermined current to the coil 52, an electromagnetic force is generated by the magnetic field in the cylindrical groove, and the drive shaft 53 is urged in the vertical direction.
[0020]
The control device 13 receives the vibration signal detected by the acceleration sensor 12 via the terminal block 41, and controls the driving force of the coil 52 so that the force acts in the opposite direction. The amplifier 14 receives an instruction from the control device 13 and supplies a predetermined current to the coil 52 via the terminal block 62 to which the amplifier 14 is connected and the terminal block 55 to which the coil 52 is connected.
As a result, vibration in the direction opposite to the vibration detected by the acceleration sensor 12 is generated in the coil 52, and the vibration isolation table 4 is driven via the drive shaft 53. Therefore, vibration transmitted from the outside is instantaneously absorbed and removed. The shaking object can always maintain a certain position.
[0021]
Next, the vibration isolation operation of the vibration isolation device 100 of the present embodiment configured as described above will be described. First, in the vibration isolation device 100, the base 6 is fixed to the base 10, but it is conceivable that vibrations in the lateral direction and the vertical direction from the outside are transmitted to the vibration isolation object that dislikes vibrations through the base 10.
[0022]
In the vibration isolator 100, the horizontal vibration transmitted from the base 10 is suppressed by the upper plate spring 91 and the lower plate spring 92, and these plate springs act as an original spring system with respect to the vertical vibration. Therefore, the vibration isolation table 4 is affected only by the vertical vibration. Therefore, it is only necessary to control the vibration in the vertical direction.
[0023]
More specifically, when the base 10 is slightly displaced upward due to vibration, the vibration isolation table 4 tries to displace upward as well, but when the vibration isolation table 4 starts to be displaced upward, the acceleration sensor The acceleration is detected by 12, and the acceleration signal is transmitted to the control device 13. The control device 13 generates a control signal that acts in the opposite direction to the detected acceleration signal so that the acceleration becomes zero, and transmits the control signal to the amplifier 14. The amplifier 14 amplifies the received control signal and supplies a current to the coil 52. Then, a force is generated in the coil 52 housed in the cylindrical groove provided in the magnet 51, and the drive shaft 53 is urged downward.
That is, since the vibration isolation table 4 receives a downward force by the drive shaft 53, the upward displacement of the vibration isolation table 4 can be suppressed as a result, and the vibration isolation table 4 can be maintained at a predetermined position. .
[0024]
Even when the base 10 is slightly displaced in the downward direction, the vibration isolation base 4 receives a reverse force in the same manner, so that the actuator 5 can act regardless of whether the base 10 vibrates in the vertical direction. The vibration isolation is performed, and the vibration isolation target installed on the vibration isolation object mounting stage 1 can always maintain a certain position.
[0025]
As described above, according to the vibration isolation device 100 of the present embodiment, since vibration is performed by passing a current through the actuator 5 including the magnet 51 and the coil 52 and controlling it, the quick response is excellent. It can be set as a vibration isolator. In addition, since the structure can be easily reduced in size, even in the case of a device or a component having a small vibration isolation target, a space can be saved as a small vibration isolation device suitable for this.
Further, by providing the upper plate spring 91 and the lower plate spring 92 in two upper and lower stages, it is possible to expect an effect of further increasing the support rigidity by the plate spring.
[0026]
In the above embodiment, one embodiment of the vibration isolator according to the present invention has been described. However, the present invention is not limited to the above-described embodiment, and various modifications can be made. . For example, the number of cylindrical grooves provided in the magnet 51 and the number of coils 52 accommodated in the cylindrical grooves is four, but any number is possible.
In addition, the upper plate spring 91 and the lower plate spring 92 are provided in two upper and lower stages, but any number may be used.
[0027]
【The invention's effect】
According to the first aspect of the present invention, when the vibration isolator provided with the vibration isolation table is slightly displaced by external vibration, the vibration detection means installed on the vibration isolation table detects the vibration of the vibration isolation table, In response, the control means controls the actuator so as to suppress the vibration of the vibration isolation table. More specifically, since a magnetic field is formed in the gap of the actuator, an electromagnetic force is generated in the gap when a predetermined current is supplied from the control means to the coil portion accommodated in the gap. The unit is driven in the vertical direction. By controlling this driving force to be about the same as the external vibration and in the opposite direction, the actuator drives the vibration isolation table in the opposite direction to the vibration direction. The position of the vibration isolation table can be kept constant.
Therefore, since the actuator is operated by current control, there is no need for a pump or a valve as in the case of a hydraulic actuator, and it is possible to provide a vibration isolation device that is easier to reduce in size and more excellent in quick response.
[0028]
In particular, when the vibration from the outside extends not only in the vertical direction but also in the horizontal direction, the leaf spring acts as an original spring system by bending the leaf spring to the force in the vertical direction. In order to suppress the vibration, the vibration isolation table is elastically supported on the base of the vibration isolation device by using a leaf spring, so that only the vibration in the vertical direction capable of vibration isolation can be transmitted to the vibration isolation table. Therefore, it is sufficient for the vibration isolator to eliminate the influence of only the vibration in the vertical direction, and more reliable vibration isolation can be performed.
[Brief description of the drawings]
FIG. 1 is a front view of a vibration isolation device according to the present invention.
FIG. 2 is a plan view of the vibration isolator according to the present invention.
3 is a cross-sectional view of the vibration isolator according to the present invention, taken along line AA in FIG.
FIG. 4 is a block diagram showing a configuration of a vibration isolation device according to the present invention.
[Explanation of symbols]
100 Vibration Isolator 4 Vibration Isolator 5 Actuator 52 Coil (Coil)
6 Base 91 Upper leaf spring (leaf spring)
92 Lower leaf spring (leaf spring)
12 Acceleration sensor (vibration detection means)
13 Control device (control means)

Claims (1)

A vibration isolation device that directly or indirectly mounts a vibration isolation object on a vibration isolation table, and isolates vibrations from outside so as not to be transmitted to the vibration isolation object.
An actuator for driving the vibration isolation table;
Vibration detecting means for detecting vibration of the vibration isolation table;
Control means for feeding back the output of the vibration detection means and controlling the actuator to suppress vibration of the vibration isolation table,
The actuator generates an electromagnetic force by supplying an electric current to a coil portion housed in a gap formed with a magnetic field, thereby driving the coil portion in the vertical direction to connect the removal portion connected to the coil portion. Configured to drive the shaking table ,
Upper leaf spring fixing members are installed at both left and right ends of the vibration isolation table,
Lower leaf spring fixing members are installed at both left and right ends of the base,
One end of the upper leaf spring is fixed to the upper leaf spring fixing member,
One end of a lower leaf spring is fixed to the lower leaf spring fixing member,
The other ends of the upper leaf spring and the lower leaf spring protrude toward the outside of the base, and are fixed to the leaf spring fixing plate separated from the vibration isolation table and the base,
The upper leaf spring fixed to the vibration isolation table by the upper leaf spring fixing member and the lower leaf spring fixed to the base by the lower leaf spring fixing member bend up and down according to the vertical vibration of the base. Accordingly, the vibration isolation table is elastically supported above the base .

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