JP3282303B2 - Exciter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of applying a desired vibration to a measuring instrument or the like to check the influence of the vibration on the measurement result, and to examine the effect of the vibration of a flexible portion inside the object when the object is not a true rigid body. The present invention relates to a vibration device for performing a destructive inspection or the like.

[0002]

2. Description of the Related Art In general, a vibration device gives a desired vibration to a measuring instrument or the like, thereby examining the influence of the vibration on a measurement result, and when an object is not a true rigid body, it is destroyed by vibration of a flexible portion inside the object. Used to perform inspections and the like.

There are two types of vibrating devices, a constant acceleration type and a constant amplitude type. The constant acceleration type detects vibration on a surface plate to be vibrated by a vibration sensor and keeps the acceleration constant. This method changes the excitation frequency.The constant amplitude type uses a position sensor to detect the amplitude of vibration on the surface plate to be excited, and changes the excitation frequency while keeping the vibration amplitude of the surface plate etc. constant. It is a way to make it. According to the constant acceleration type, the amplitude of the vibration decreases as the frequency increases, and according to the constant amplitude type, the acceleration increases as the frequency increases. In any case, an actuator and a vibration sensor are arranged between the surface plate and the floor surface, the vibration sensor detects the vibration of the surface plate, and drives and controls the actuator so that the vibration becomes a desired vibration. ing.

[0004]

However, according to the above-mentioned method, since the actuator for generating the vibration of the surface plate receives a reaction force from the floor, the vibration caused by external transportation or the vibration of the earthquake. When the floor is vibrating due to, for example, the actuator is driven based on the vibration detected by the vibration sensor, extra vibration from the floor surface is added, making it difficult to accurately apply the desired vibration to the surface plate. Met.

A method of installing a vibrating device on a vibration removing device to eliminate vibration from the floor is also considered. However, since the vibrating device itself is heavy, the device becomes large as a whole. . In addition, when the vibrating device is installed on the vibration removing device, the force points acting on the surface plates of the two devices do not coincide with each other, so that it becomes a factor that hinders the reduction of vibration from the floor surface, and the desired vibration is given. Can not.

The present invention has been made in order to solve these problems. By connecting a pneumatic cylinder and a coil actuator in series, the driving force of these driving forces coincides with the power point acting on the surface plate. It is an object of the present invention to provide a vibration device capable of giving desired vibration to a surface plate even when a floor surface vibrates.

[0007]

Means for solving the problems of the present invention will be described with reference to FIGS. 1 and 2 which are one embodiment of the present invention. The vibration device according to the present invention includes a surface plate 2 on which an object is placed, and a vibration sensor 6 for detecting vibration of the surface plate 2.
A pneumatic cylinder 1c provided in the base 1 to support the surface plate 2, a loose fitting hole 23 recessed in the surface plate 2 and having a magnet 3a embedded in a side surface thereof; A coil actuator 3 formed by loosely fitting a coil 3b erected on the base 1 into a loose fitting hole 23 having a magnet 3a embedded in the side surface;
A target vibration generating means 4a for generating a signal of a desired vibration function to be given to the surface plate 2, a difference supplying means 4b for supplying a difference between the signal of the vibration function and the signal of the vibration sensor 6 to the coil actuator 3; Control means 4 comprising
And characterized in that:

[0008]

The operation of the present invention will be described with reference to FIGS.
A difference between the signal indicating the vibration of the base 2 detected by the vibration sensor 6 and the vibration function signal output from the target vibration generation means 4a is obtained by the difference supply means 4b, and supplied to the coil actuator 3 via the amplifier 8. You. Thereby, the coil actuator 3 drives the surface plate 2 so that the signal detected by the vibration sensor 6 approaches the vibration function signal. At this time, since the pneumatic cylinder 1c and the coil actuator 3 are connected in series, the power points at which these driving forces act on the platen 2 coincide, and the vibration of the floor surface absorbed by the pneumatic cylinder 1c is reduced. And it is not transmitted to the surface plate 2. Therefore, the vibration control can be performed in substantially the same environment as when the floor surface has no vibration, and the desired vibration can be given to the surface plate 2 with higher accuracy.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1, 2 and 3. FIG. ◎ FIG. 1 is a view showing an embodiment of a mechanism section of a vibration device according to the present invention, wherein 1 is a base having a cylindrical shape, having a hollow portion therein, and the hollow portion being separated. The wall 15 is divided into a first chamber 11 and a second chamber 12, and the separation wall 15 has a through hole 13 narrowed on one side. Then, an air input / output unit 16 is formed on the cylindrical side surface of the first chamber 11, from which air is supplied to the first chamber 11. The upper part of the first chamber 11 is covered with an elastic body 14 whose end is fixed to the side wall of the first chamber 11, and the first chamber 11 forms an air spring 1a. The lower portion of the elastic body 14 is supported by the elastic support 18 so that the mounting portion of the drive shaft 22 of the surface plate 2 described later is kept in a planar shape. Also, the through holes 13 in the separation wall 15
The air damper 1b is configured by maintaining the second chamber 12 at a predetermined pressure by the air press-fitted through the air. The air spring 1a and the air damper 1b form a pneumatic cylinder 1c, which enables the platen 2 to be separated from the floor and mounted. In this embodiment, FIG.
Although the pneumatic cylinder 1c is constituted by the air spring 1a and the air damper 1b as shown in FIG. 1, the pneumatic cylinder 1c may be constituted by only the air damper 1b. In this case, the separation wall 1
5 may be eliminated and the air pressure in the hollow portion may be kept constant. Reference numeral 17 denotes a support for mounting the drive shaft 22 of the base 2 when the pneumatic cylinder 1c is not operating.

Reference numeral 2 denotes a base plate, a table 21 on which an object is placed, a drive shaft 22 for transmitting the urging force of the pneumatic cylinder 1c to the table 21 below, and an end of the drive shaft 22 which will be described later. It has a loose fitting hole 23 for loosely fitting the coil 3b. The platen 2 is placed on the support portion 17 of the base 1 when the pneumatic cylinder 1c is not driven, and is supported via the elastic portion 14 by the urging force of the pneumatic cylinder 1c when driven.

Reference numeral 3 denotes a coil actuator, a coil 3b standing upright on the base 1 and loosely fitted in a loose fitting hole 23 of the surface plate 2.
Magnet 3a buried in the side wall of loose fitting hole 23 of surface plate 2
And the magnetic body 3c. The coil actuator 3 urges the drive shaft 22 of the platen 2 by an electromagnetic force generated by a predetermined current supplied to the coil 3b. FIG. 2 is a block diagram showing the configuration of the present invention.
Coil actuator 3, air spring 3a shown in FIG.
1, a mechanism unit including a position sensor 5 and a vibration sensor 6 not shown in FIG. 1, a control unit 4 for controlling the driving force of the coil actuator 3 and the air spring 1a, and a coil actuator receiving instructions from the control unit 4. An amplifier 8 for supplying a predetermined current to the air spring 3 and an air pump 7 for supplying air of a predetermined pressure to the air spring 1a in response to an instruction from the control means 4 are shown. The position sensor 5 detects the height of the table 21 of the surface plate 2 and includes an infrared sensor, and the vibration sensor 6 detects the vibration of the surface plate 2 and includes a speed sensor, an acceleration sensor, and the like.

Here, the control means 4 includes the target vibration generating means 4
a, a difference supply unit 4b, a target position generation unit 4c, and a second difference supply unit 4d. The target vibration generating means 4a generates a vibration function signal representing a desired vibration to be given to the surface plate 2, and the difference supply means 4b supplies a difference between the vibration function signal and the signal detected by the vibration sensor 6 to the amplifier 8. I do. Thus, the coil actuator 3 drives the surface plate 2 so that the signal of the vibration sensor 6 approaches the vibration function signal, so that it is possible to give a desired vibration to the surface plate 2. The target vibration generating means 4 is configured to freely set a desired vibration function, for example, various functions such as a sine wave and a sawtooth wave. On the other hand, the target position generating means 4c
Generates a signal indicating the desired height position of the surface plate 2, and the second difference supply means 4d calculates the difference between the signal provided by the target position generation means 4c and the signal detected by the position sensor 5 in the air. Supply to pump 7. Thereby, the air spring 1
In a, the surface plate 2 is driven so that the signal of the position sensor 5 approaches the signal value of the target position generating means 4c, so that the surface plate 2 can be maintained at a desired height.

The operation of the vibration device configured as described above will be described with reference to the mechanism diagram of FIG. 1, the block diagram of FIG. 2, and the flowchart of FIG. First,
In a state where air of a predetermined pressure is not press-fitted into the pneumatic cylinder 1c, the base 2 is placed on the support portion 17 of the base 1, and
The entire weight of the surface plate 2 is directly supported by the base 1 via the support portion 17.

First, in S1 of FIG. 3, a desired vibration function to be given to the surface plate 2 is set in the target vibration generating means 4a. The vibration function represents a desired vibration such as a sine wave or a sawtooth wave. Next, the target set value of the position sensor 5 is set in the target position generating means 4c in S2, and the signal of the position sensor 5 is read in S3. The second difference supply means 4d of the control means 4 supplies the difference between the target set value set in S2 and the signal of the position sensor 5 to the air pump 7, and the platen 2 corresponds to the target set value of the position sensor 5. The air pressure of the air spring 1a is increased so as to approach the position (S4). Next, proceeding to S5, the signal of the vibration sensor 6 is read. In S6, the difference signal between the vibration function signal based on the vibration function set in S1 and the signal detected by the vibration sensor 6 is output to the coil actuator 3 via the amplifier 8. To supply. Then, the above-mentioned S1 to S6
By repeating the above operation, the vibration indicated by the desired vibration function set by the target vibration generating means 4a is generated while maintaining the height of the surface plate 2 at the height set by the target position generating means 4c. Can be.

As described above, according to the present invention, the configuration in which the coil actuator 3 and the pneumatic cylinder 1c are connected in series is employed, so that these driving forces can be applied to substantially the same position on the surface plate 2. . For this reason, the vibration of the floor surface is absorbed by the pneumatic cylinder 1c, and is hardly transmitted to the coil actuator 3. Therefore, even when the floor is vibrating due to vibrations caused by external transportation or the like, vibrations due to earthquakes, it is possible to create a substantially vibration-free environment on the pneumatic cylinder 1c. Excitation control of the platen 2 by the coil actuator 3 can be performed with the same accuracy as in a state where no vibration occurs.

Further, as shown in FIG. 1, by adopting a configuration in which the base 2 is mounted on the pneumatic cylinder 1c of the base 1, the entire weight of the base 1 can be supported by the pneumatic cylinder 1c. For this reason, the coil actuator 3 provided on the pneumatic cylinder 1c does not need to support the weight of the surface plate 2, and more precise vibration control can be performed.
As shown in the embodiment, the pneumatic cylinder 1c is composed of the air damper 1b and the air spring 1a, and the position sensor 5,
If the target position generating means 4c, the second differential supply means 4d and the air pump 7 are combined, it is possible to freely adjust the height which is the center of the vibration of the surface plate 2.

[0017]

The vibrating device according to the present invention employs a structure in which a pneumatic cylinder and a coil actuator are connected in series, so that these driving forces can be applied to substantially the same position on the surface plate. Therefore, vibration of the floor surface is not transmitted to the coil actuators arranged in series on the pneumatic cylinder, and vibration control of the surface plate by the coil actuators is performed with the same accuracy as when the floor surface is not vibrating. Becomes possible.

Further, since the platen is mounted on the pneumatic cylinder, the entire weight of the base can be supported by the pneumatic cylinder. For this reason, the coil actuator provided on the pneumatic cylinder does not need to support the weight of the surface plate, and more precise vibration control can be performed.

[Brief description of the drawings]

FIG. 1 is an embodiment showing a mechanism section of the present invention.

FIG. 2 is a block diagram showing one embodiment of the present invention.

FIG. 3 is a flowchart illustrating an operation of a control unit.

[Explanation of symbols]

 1 Base 1a Air spring 2 Surface plate 3a Magnet 3b Coil 3 Coil actuator 4 Control Means 4a... Target vibration generating means 4b.

Claims (1)

(57) [Claims] 1. A surface plate on which an object is placed, a vibration sensor for detecting vibration of the surface plate, a pneumatic cylinder disposed in a base for supporting the surface plate, and a recess provided in the surface plate. A loose fitting hole in which a magnet is embedded in the side surface, and a coil erected on the base, and the coil erected on the base is loosely fitted in the loose fitting hole in which the magnet is buried in the side surface. A formed coil actuator; target vibration generating means for generating a signal of a desired vibration function to be given to the surface plate; and a difference supply for supplying a difference between the signal of the vibration function and the signal of the vibration sensor to the coil actuator. And a control means comprising: