KR101704532B1 - Vibration regulation digital control system - Google Patents

Abstract

The present invention relates to an integrated vibration suppression digital control system, and more particularly, to an integrated vibration suppression digital control system using passive, semi-active, and active control type mount modules for integrally controlling environmental vibration and transient response vibration generated during operation of ultra- To a digital control system. According to the present invention, it is possible to minimize the deterioration of the signal due to the analog wiring by controlling the environment vibration and the transient response vibration generated during the operation of the ultra-precision equipment in a digital control system which is insensitive to noise and has excellent environmental resistance, It is possible to maintain a uniform control characteristic even if the shape and size of the vibration damping base are different.

Description

[0001] VIBRATION REGULATION DIGITAL CONTROL SYSTEM [0002]

The present invention relates to an integrated vibration suppression digital control system, and more particularly, to an integrated vibration suppression digital control system using passive, semi-active, and active control type mount modules for integrally controlling environmental vibration and transient response vibration generated during operation of ultra- To a digital control system.

Currently, the level of vibration environment required in semiconductors, display production lines, and other precision measurement / processing lines is becoming very strict, and the existing manual control method has already reached its limit. a reduction in settling time due to transient vibration control caused by switching from a stepping method to a high-speed scanning method is directly linked to the improvement of productivity.

An active control is a method of reducing vibration by applying a force opposite to an exciting force that causes vibration. The integrated mount includes an anti-vibration device for blocking the excitation force, a semi-active type vibration damper for generating control force, to be.

As the development speed of integration and enlargement of super precision products such as semiconductors and displays increases, economic loss due to reduction in productivity and yield due to vibration occurs. As the existing passive vibration countermeasures show limitations, the need for an active vibration control system has been greatly increased and it is a system that is urgently required to be applied in the field at present.

Active mounts developed in Japan and USA have difficulties in domestic application due to various problems (performance dissatisfaction, difficulties in A / S, etc.) even though they are expensive. Recently, there have been many improvements in performance, have. In particular, there is a problem that time and engineering cost are large due to reliance on foreign technology for solving technical problems that arise when the system is applied.

KR 10-2012-0122706 A

SUMMARY OF THE INVENTION The present invention has been made to overcome the above problems, and it is an object of the present invention to provide an integrated vibration damper utilizing a passive, semi-active, and active control type mount module capable of integrally controlling environmental vibration, transient response vibration, And to provide a digital control system.

According to an aspect of the present invention, there is provided a vibration damping mount apparatus including: an air spring (410) for canceling a load applied from an upper portion; And the lower end of the air spring 410 is opened and connected to the lower portion of the load supporting portion 415 of the air spring 410 so as to vibrate in the MR fluid 430 in accordance with the vibration of the air spring 410, The air spring 410 includes a cylindrical side wall 412 having a space therein and an upper end of the side wall 412 and an elastic member 413 And a load supporting portion 415 connected to the load plate connecting rod 21 on the upper side and the other side connected to the upper plate 414. The vibration mount device 400 includes an upper A tubular damper housing 421 installed inside the spring 410 and having a bottom and an opened upper surface; A MR fluid 430 filled in the damper housing 421; A cylindrical core 441 fixed to the inner bottom surface 422 of the damper housing 421; And a coil (442) wound around the core (441), wherein the cage (450) is connected to a lower portion of the load support portion (415) The cage 450 is formed in a state parallel to the surface of the MR fluid 430 and moves downward according to a load. And a cage side surface portion 452 connected to the lower portion of the membrane 451 and having an open bottom and an inner cylindrical shape. The cage side surface portion 452 is made of a material that blocks the flow of a magnetic field.
The cage side surface portion 452 may have a plurality of holes 453 through which a magnetic field generated as current flows in the coil 442.
The membrane 451 may be made of an elastic material.

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According to the present invention, it is possible to minimize the deterioration of the signal due to the analog wiring by controlling the environment vibration and the transient response vibration generated during the operation of the ultra-precision equipment in a digital control system which is insensitive to noise and has excellent environmental resistance, It is possible to maintain a uniform control characteristic even if the shape and size of the vibration damping base are different.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows an integrated damping system in accordance with an embodiment of the present invention.
2 is a signal flow diagram of the integrated damping system in FIG.
3 is a conceptual diagram of an integrated vibration suppression digital control system;
4 is a linearization block diagram of an integrated vibration damping system;
5 is a configuration diagram of an integrated vibration damping controller;
6 is a diagram showing main features of a digital signal processing unit for processing an integrated vibration suppression algorithm;
7 is a diagram showing a process of transferring information between an integrated damping upper controller and a main controller.
8 is a diagram showing an overview of integrated vibration damping information transmission;
9 is a view showing an integrated vibration damping system communication time;
10 shows a monitoring program.
11 is a view showing a vibration damping mount apparatus according to the present invention.
12 is a photograph showing two embodiments of a cylindrical side portion of a cage.
Fig. 13 is a graph showing an embodiment of vibration damping characteristics when MR fluid is used as paraffin. Fig.
14 is a graph showing one embodiment of the damping characteristics when MR fluid is used as silicon.
15 is a view showing a displacement detection device according to the present invention.
16 is a diagram showing a change in impedance due to the generation of an eddy current according to the present invention.
17 is an equivalent circuit diagram showing an electromagnetic relationship between a coil and a detection object according to the present invention.
18 shows a concept of an oscillator of a displacement detection device according to the present invention.
19 is a graph showing characteristic curves of a displacement detection device according to the present invention.
20 A graph showing a curve fitting of a displacement detection device according to the present invention.
21 is a graph showing a sensitivity curve of the displacement detection device according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be interpreted in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined. Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

FIG. 1 is a view showing an integrated vibration damping system according to an embodiment of the present invention, and FIG. 2 is a signal flow diagram of an integrated vibration damping system in FIG.

As shown in the figure, the integrated vibration damping system of the present invention is comprised of a stone column 10, a moving mass 20, and four integrated mounts 30.

The integrated mount 30 is composed of an air spring 31, an MR damper 32 and a magnetic actuator 33, respectively.

The movement of the stone pedestal 10 in accordance with the movement of the disturbance or the moving mass 20 is measured by the gap sensor 40 and the speed sensor and the displacement sensor and is transmitted to the DSP controller 50.

Since signals in the z, pitch, and roll directions are coupled to the sensor signal, they are decomposed into orthogonal coordinates by a decoupling algorithm. Then, the control signal is synthesized into a control signal for each mount via a control algorithm, and then transmitted to an air spring 31, an MR damper 32, and a magnetic actuator 33 Real-time control is enabled.

The air spring 31 of the integrated mount 30 is controlled using a proportional valve 60 for intake / exhaust. The proportional valve 60 adjusts the pressure of the air spring 31 to perform leveling, large vibration compensation, and the like.

The DSP controller 50 performs control algorithm operation and generation of drive commands for the air spring 31, the MR damper 32 and the magnetic actuator 33 and the generation of the drive command for the magnetic actuator (33).

An actuator controller 70 controls an air spring 31 and an MR damper 32. [

FIG. 3 is a conceptual diagram of an integrated vibration suppression digital control system, and FIG. 4 is a linearization block diagram of an integrated vibration suppression system.

As shown in the figure, the integrated vibration damping system uses a dynamic characteristic of an air mount 30, an MR damper 32, and a magnetic actuator 33 to perform a vibration damping / . A conceptual diagram of a digital control system composed of the actuator components and the DSP controller 50 is shown in FIG.

The proportional control valve 60 controls the number of air moles in the air mount 30 to produce air pressure and the MR damper 32 generates a damping force controlled by the current . The Magnetic Actuator 33 also generates an Electro-Magnetic Force by the current. Each component has a nonlinear characteristic, but can be represented by the block diagram of Fig. 4 if the system is linearized with respect to a minute displacement.

The physical quantity related to the system dynamic characteristics such as the mount displacement and the speed of the integrated vibration damping system is a continuous analog signal. However, in order to perform the control by the DSP controller 50, a sampling process for converting the digital data to a digital time is required. After passing through a control algorithm module 80 for a sampled discrete signal, the signal is converted into an analog signal through a holder (not shown) to be supplied to an MR damper 32, A proportional control valve 60 and a magnetic actuator 33. The control unit 60 controls the proportional control valve 60 and the magnetic actuator 33,

The integrated vibration suppression system consists of a digital control system that is insensitive to noise and has excellent environmental resistance, rather than a signal transmission system based on analog noise, which is sensitive to external noise. (MR damper) 32, a proportional control valve 60 and a driving part of a magnetic actuator 33 and a gap sensor 40 as well as a control algorithm for facilitating commercialization of the product, (CAN) communication.

Such a digital communication method can minimize signal deterioration due to analog wiring, so it has a strong characteristic against external noise, and uniform control characteristics can be maintained even if the shape and size of the vibration eliminator are different.

* In digital control method, analog signal to digital conversion process is inevitably required, and appropriate sampling time (sampling time) is required to minimize system load while minimizing communication load.

FIG. 5 is a block diagram of an integrated vibration damping controller, and FIG. 6 is a diagram showing main features of a digital signal processor for processing an integrated vibration damping algorithm.

As shown in the figure, the integrated vibration damping controller of the present invention includes a DSP main controller, an MR damper controller, a pneumatic controller, a magnetic actuator controller, Controller, sensor controller, and so on. Since a plurality of controllers for MR damper / pneumatic / magnetic actuator are used, a total of eleven control boards and feedforward sensor boards constitute the system.

The integrated damping controller is designed to be housed in an industry standard 19-inch rack, designed for practicality and mounting. The control board which is accepted is connected to the bus structure by DIN41612D connector which is verified by industry.

Hereinafter, each controller constituting the integrated vibration damping controller will be described.

DSP Main Controller

The real-time control algorithm uses a high-performance embedded DSP processor-based control board to process the integrated vibration suppression algorithm. The controller incorporates an FPGA (Field Programmable Gate Array) and 516 KByte SRAM to process real-time algorithms and communicate with external devices (sensors, actuators) via two CAN (CAN) communications.

In order to minimize the influence of the electric noise that may occur in the field, the input power is insulated by a DC-DC converter, and CAN communication is configured to enable insulation communication by using a full null photo coupler.

The main role of the DSP main controller 50 is as follows.

- Gap Sensor (40) Signal Processing

- Control algorithm operation

- Generate component drive command

  MR damper 32 is driven

  Air Spring Drive

  Pneumatic Actuator Drive

  Magnetic Actuator 33 is driven

  Sensor Controller Control

- Isolated CAN communication (125KBps ~ 500KBps)

An apparatus for processing an integrated vibration suppression algorithm comprises a digital signal processor (DSP) and a field programmable gate array (FPGA) for processing an integrated vibration suppression algorithm. A field programmable gate array (FPGA) for processing the integrated vibration suppression algorithm is responsible for high speed digital logic signal processing. It consists of a number of CLB (Configurable Logic Block) and IOB (Input Output Block) DCM (Digital Clock Manager) and so on to get smooth operation without delay.

MR damper / magnetic actuator complex controller

The MR damper 32 and the magnetic actuator 33 control the driving of the MR damper 32 and the magnetic actuator 33, which are integrated vibration suppression components. The MR damper controller consists of a microprocessor, a constant-current driver interface, a full-bridge constant current driver capable of forward and reverse operations, an analog-to-digital converter (ADC), and a CAN communication port.

The microprocessor has real-time real-time arithmetic functions and is designed to reduce power consumption and enable high-speed operation using a low 3.3 V power supply. The constant current driver interface is designed to be robust against external electrical noise by being separated from the driver circuit (option) by an electrically isolated high speed optocoupler.

The MR damper controller basically uses 24V input-1.8A constant current output type PWM driver method. The direction of the driving current can be switched so as to eliminate the residual magnetic flux generated when a current flows in the MR damper 32 in one direction. The current flowing in the MR damper 32 is converted into an analog-to-digital converter (ADC) and transmitted to the microcomputer. In a multipurpose current driver, the maximum current supplied to the MR damper is 1.8 A and the PWM frequency is 10 to 20 KHz.

The main features of the MR damper controller are as follows.

- 24V 1.8A Current Driver

- PWM Frequency: 10 ~ 20KHz

- TMS320F28335 Floating Point Microprocessor

- Isolated CAN communication (125KBps ~ 500KBps)

- Power Isolation

- H-Bridge drive circuit electrical isolation

- Built-in non-connection check function

Pneumatic Controller

The pneumatic controller is responsible for driving the air spring and pneumatic actuator, which are integrated vibration suppression components. The pneumatic controller consists of a microprocessor, a 4 to 20 mA current driver, a constant current driver interface, a full-bridge constant current driver capable of forward and reverse operation, an analog to digital converter (ADC) do.

The microprocessor has real-time real-time arithmetic functions and is designed to reduce power consumption and enable high-speed operation using a low 3.3 V power supply. The constant current driver interface is designed to be robust against external electrical noise by being separated from the driver circuit (option) by an electrically isolated high speed optocoupler.

The output section of the pneumatic controller consists of a 4 to 20 mA output section for proportional control valve control and a 1.2 A constant current output PWM driver section for solenoid valve control.

The main features of the pneumatic controller are as follows.

- TMS320F28335 Floating Point Microprocessor

- 24V 1.2A Current Driver (PWM Frequency: 10 ~ 20KHz)

- 4 ~ 20mA Current Driver

- Isolated CAN communication (125KBps ~ 500KBps)

- Power Isolation

- H-Bridge drive circuit electrical isolation

Sensor Controller

The sensor controller is responsible for measuring the displacement of the gap sensor (40) and delivering it to the DSP main controller (50). The sensor controller consists of a microprocessor, a Gap Sensor Wave Shaping Circuit, an Analog Signal Conditioning Amplifier, an analog-to-digital converter (ADC), and a CAN communication unit.

The microprocessor is designed to operate at speeds from 50MHz to 70MHz, reducing power consumption by using a low 3.3V supply, capable of handling up to 4CH gap sensor signals, and an independent 2-channel analog - Built-in digital conversion device. The sensor controller is designed to accommodate low resolution mode and high resolution mode. It can process up to two gap signals in high resolution mode and four channel signal processing in low resolution mode.

The main features of the sensor controller are as follows.

- High resolution mode: 2 Ch Gap Sensor signal processing

- Low resolution mode: 4 Ch Gap Sensor signal processing

- STM32F103 Cortex-M3 Microprocessor

- Isolated CAN communication (125KBps ~ 500KBps)

- Power Isolation

Linux Controller

The Linux controller 90 manages variables (mount position, sensor position, etc.) necessary for the operation environment of the integrated anti-vibration DSP main controller algorithm and manages the MMI (Man-Machine Interface).

Hereinafter, the integrated vibration damping controller control algorithm will be described.

The integrated vibration suppression device controls the driving force of the pneumatic spring, the MR damper, and the magnetic actuator through the vibration control algorithm based on the sensor information to suppress the vibration of the system.

In order to perform this operation, various alternatives can be considered according to the communication method between the apparatus (main controller - lower controller, etc.) and the sampling interval. In the present invention, the control period is set to 250 Hz in consideration of the scalability and stability of the system, and the communication method between apparatuses uses CAN communication of 500 KBps.

For the real-time control of the system, the Kalman Filter, the system-to-system decoupling algorithm, and the inter-device communication should be performed in a limited time. For this, each algorithm that requires sequential operation determines the algorithm structure so that the actual waiting time is minimized by scheduling the algorithm / waiting time per algorithm faster than the control period.

In addition, a software-based queue is used to separate the transmission information registration and the transmission portion so that the microprocessor does not wait for the waiting time during communication between devices requiring a relatively long time (1.75 ms).

7 is a view showing a process of transferring information between the integrated damping upper controller and the main controller.

As shown in the figure, the control parameters of the integrated vibration damping controller are several hundred kinds, and the QT-based host controller manages the environment variables so that each parameter can be easily controlled.

FIG. 8 is a diagram showing an overview of integrated vibration damping information transmission, and FIG. 9 is a diagram showing communication time of an integrated vibration damping system.

As shown in the figure, by using such a digital communication method, signal deterioration due to analog wiring can be minimized, and therefore, it is possible to maintain robust characteristics against external noise and to maintain uniform control characteristics even when the shape and size of the anti- have.

When the baudrate of the CAN communication is 500 KBps, the CAN communication 1 packet transmission time is

이다.

to be.

범위로 정한다. 이때,

의 소요시간에 대한 부담을 경감하도록 캔(CAN)의 보 레이트(Baudrate)를 500kbps로 정한다.The Nyquist diagram of the system including the proportional valve 60 is shown in FIG. Since the gain margin in the low-frequency range is very small, it is possible to suppress the phase delay due to possible sampling

Range. At this time,

The baud rate of the can (CAN) is set to 500 kbps so as to reduce the burden on the time required for the can.

The communication time required to control each of the MR damper 32, the air servo valve, and the magnetic actuator 33 in the DSP main controller is about 1.75 ms.

10 is an illustration of a diagram showing a monitoring program developed for application of the present system.

As shown, the detailed static / dynamic parameters such as the size of the stone crest, the load and the dynamic behavior of the mount should be managed according to the characteristics of the equipment to which the integrated vibration damping system is applied, and the corresponding parameters should be reflected in the control algorithm.

This monitoring program is used for such data management and MMI (Man Machine Interface).

The functions of the monitoring program are as follows.

- QT Base Program

- Operation mode setting (Operation mode / Installation mode)

- Real-time display of component status

- Storage and management of dynamics data

- System Parameter Setting (UDP Protocol)

This monitoring program was developed as QT and can be applied to various desktop and embedded operating systems through cross compilation without rewriting source code.

Fig. 11 is a view showing a vibration-damping mount apparatus 400 according to the present invention, Fig. 12 is a photograph showing two embodiments of cylindrical side portions 452 of a cage 450 in the vibration damping mount apparatus 400 to be. The vibration damping mount apparatus 400 described below may be installed at a plurality of positions under the load plate 20. [ The vibration damping mount apparatus 400 shown in Fig. 11 shows the integrated mount 30 in the integrated vibration damping system of Fig. 1, which will be described in detail below.

On the load plate (20), vibration sensitive equipment such as semiconductor equipment, precision inspection equipment, etc. is placed. The load plate 20 is preferably made of a heavy material so as not to be affected by the vibration as much as possible. The air spring 410 is connected to the lower portion of the load plate 20 through the load plate connecting rod 21. The air spring 410 primarily receives the vibration applied to the lower portion through the load plate and serves to cancel the vibration. The air spring 410 has a bottom surface 411 and a cylindrical side wall 412. It also has a top plate 414, which is connected via a resilient member 413 to the top plate 414. One of the load supporting portions 415 is connected to the upper plate 414 and the other is connected to the load plate connecting rod 21. In other words, the elastic member 413 and the upper plate 414 and the load supporting portion 415 connected to the elastic member 413 act to primarily cancel the vibration while receiving the vibration according to the vibration of the load plate 20.

The damper 420 is installed inside the side wall 412 of the air spring 410. The damper 420 has a bottom surface 422 and a cylindrical housing 421 on the side surface, and the MR fluid 430 is filled therein. The core 441 is fixed to the damper bottom surface 422 in the MR fluid inside the damper housing 421 so that the coil 442 is wound around the core and the current flowing in the coil 442 A magnetic field is generated by the magnetic field, and the viscosity of the MR fluid is further increased by the generation of such a magnetic field, so that the damping force can be enhanced.

The core wound with the coil is fixed to the bottom surface as a piston without vertical movement. That is, in the structure according to the present invention shown in Fig. 11, the core 441 is fixed to the floor.

A cage 450 is provided under the load supporting portion 415 of the air spring so that the cage 450 vibrates in the MR fluid according to the vibration of the load plate 20. [ The cage 450 has an upper membrane 451 that contacts the MR fluid surface when it moves downward according to the load and a side surface 452 that surrounds the core in the damper housing Which side portion 452 is subjected to a damping force in the MR fluid 430. The force received by the cage side surface portion 452 from the MR fluid is relatively small, but the impact received from the MR fluid at the bottom is greatly reduced, thereby enabling more stable damping. It is preferable that the membrane 451 is made of an elastic material so that the MR fluid does not overflow when the MR fluid contacts the MR fluid.

The cage side surface portion 452 also has a plurality of holes 453. These life presences 453 can control the transfer of the magnetic field generated in the coil 442. [ That is, the cage side surface portion 452 is made of a material that blocks the magnetic field flow. By providing a plurality of holes in the cage side surface portion 452, a part of the magnetic field generated through the hole is passed. By passing some magnetic field through the holes, the MR fluid is made to have an overall higher viscosity, while the viscosity of the MR fluid inside the cage 450 is relatively greater by blocking the magnetic field through the non-hole portion of the cage side portion 452 . Thereby preventing horizontal vibration of the cage 450. As a result, the vertical vibration as well as the horizontal vibration can be improved. The number, position and area of the holes can be determined in various forms through experimentation in accordance with the required vibration damping characteristics.

FIG. 13 is a graph showing an embodiment of vibration damping characteristics when MR fluid is used as paraffin. FIG. 14 is a graph showing an embodiment of vibration damping characteristics when MR fluid is used as silicon. It can be confirmed that the case shown in Fig. 14 reduces the vibration more and gives a stable vibration damping effect when the electric current is applied.

13 and 14, the abscissa represents the vibration frequency, the ordinate represents the vibration velocity (the left axis) and the displacement (the right axis), the abscissa represents the time, and the ordinate the vibration acceleration.

15 is a view showing a displacement detecting apparatus according to a preferred embodiment of the present invention. The displacement detecting apparatus according to the present invention includes a signal generating unit 200, a signal converting unit 300, a signal processing unit 400, And a display unit. The displacement detection apparatus shown in Fig. 15 represents a gap sensor 40 in the integrated vibration damping system of Fig. 1, which will be described in detail below.

The signal generator 200 is located near the detection object 100 and includes a coil sensor 210, an oscillator 220, and a waveform converter 230.

When the coil sensor 210 is energized in proximity to the object to be detected 100, the coil sensor 210 generates an eddy current by an applied power source and generates an eddy current 210 operate in a direction of canceling each other, so that the high-frequency impedance is changed. See FIG. 16 for such contents.

17 is an equivalent circuit diagram showing an electromagnetic relationship between a coil and a detection object for explaining the present invention. The electromagnetic relationship between the coil sensor 210 and a metal object, that is, a detection object 100 is considered as a transformer . The primary coil can be represented by a winding resistance and a magnetic inductance, and the object to be detected 100 can also be expressed by an appropriate resistance and magnetic intercept. Also, since the two are electromagnetically coupled, mutual inductance acts. This relationship can be expressed by the following equation.

--- (1)Primary (coil sensor part):

--- (One)

--- (2)Secondary (detection object part):

--- (2)

(1) and (2) can be expressed as Matrix.

--- (3)

--- (3)

--- (4)

--- (4)

Because of,

을 구하면 다음과 같다.

The following is obtained.

--- (5)

--- (5)

If the equivalent impedance viewed from the primary side is Z

,

--- (7)

,

--- (7)

.

과

은 다음과 같다.therefore,

and

Is as follows.

--- (8)*

--- (8)

--- (9)

--- (9)

Also

--- (10)

--- (10)

,

은 1차 코일의 구조와 물성에 의해 결정되는 저항과 자기 인덕턴스(self-inductance)이고,

,

는 와전류경로, 비저항

, 투자율

에 의해 결정되는 저항과 자기 인던턱스이다. 또한

은 센서코일과 금속체 사이의 거리

에 의존하는 상호 인덕턴스(Mutual inductance)이다.here

,

Is a resistance and a self-inductance determined by the structure and physical properties of the primary coil,

,

The eddy current path, the resistivity

, Investment ratio

Lt; RTI ID = 0.0 > and < / RTI > Also

The distance between the sensor coil and the metallic body

Is a mutual inductance that depends on the inductance.

, 비저항

, 투자율

, 거리

의 함수이며, 내부온도

의 영향을 포함한 함수

로 나타낼 수 있다.That is, the equivalent impedance viewed from the primary side is the frequency

, Resistivity

, Investment ratio

, Street

And the internal temperature

Functions Including Effects

.

, 비저항

, 투자율

의 변동폭이 매우 작다면 다음과 같이 적절한 함수관계로 간소화할 수 있다.Of these,

, Resistivity

, Investment ratio

If the fluctuation of the frequency is very small, it can be simplified to a proper function relation as follows.

The oscillator 220 of the signal generator 200 generates a high frequency current in the displacement signal sensed by the coil sensor 210. The concept of the oscillator 220 is shown in FIG.

As shown in Fig. 18,

가 없어도 출력신호가 생성되어야 하므로,

을 만족해야 한다.Therefore, in order to stabilize the oscillation by the forward feedback,

The output signal must be generated,

.

Accordingly, in the present invention, oscillation occurs at the resonance frequency of the resonance circuit by positive feedback, and low frequency stability is improved by using negative feedback.

The waveform converter 230 of the signal generator 200 converts a displacement signal, that is, a sine wave signal, which varies depending on the distance of the detection object 100, into a square wave signal and outputs the square wave signal.

The signal converter 300 includes a position counter 320, a speed counter 330, and a controller for controlling the position counter 320 and the speed counter 330.

The position counter 320 counts pulse signals converted per clock by applying an arbitrary periodic signal to the displacement signal generated by the signal generator 200.

For example, when an arbitrary periodic signal is 20 MHs and one clock of the displacement signal is 1 ms, the pulse signal converted from the clock is counted.

The speed counter 330 divides the clock of the pulse signal counted by the position counter 320 into an arbitrary clock and counts the pulse signals in the divided clock.

For example, when the clock of the displacement signal is 1 ms, the 1 ms clock is divided by 0.2 ms, and the pulse signal converted from the divided 0.2 ms clock is counted.

Here, the relationship between the frequency change and the position counter can be expressed as follows.

ego,

= 기준 Crystal 주파수 ( 20 MHz 부근)here,

= Reference Crystal frequency (around 20 MHz)

= Tuned Oscillator 주파수 ( 300 KHz 부근)

= Tuned Oscillator frequency (near 300 KHz)

= 계측 주기 주파수 ( 200 Hz 부근)

= Measurement period frequency (near 200 Hz)

=

보다 크지 않은 최대 정수 (gauss function) 이다.

=

It is a gauss function that is not greater than.

 E.g,

 When the object approaches the sensor and the frequency changes,

= 주파수 변화율

= Frequency change rate

= 20MHz,

= 200Hz,

=0.01 인 경우

= 20 MHz,

= 200 Hz,

= 0.01

,

=

보다 크지 않은 최대 정수

,

=

The largest integer not greater than

to be.

The signal processor 400 obtains a displacement value corresponding to the pulse signal converted by the signal converter 300. The signal processor 400 multiplies the number of pulse signals generated per clock, counted by the signal converter 300, And detects the displacement and velocity of the detection object 100 at a corresponding value. That is, the displacement value can be measured by the number of pulse signals counted by the position counter 320 of the signal converter 300, and the displacement rate can be measured by the pulse signal counted by the speed counter 330 .

The signal processing unit 400 may also process the converted signals from the plurality of signal converters 300 and may table the values corresponding to the internal temperature of the detection object 100 to correct the displacement values Processing is also possible.

The display unit displays the displacement value of the detection object obtained from the signal processing unit (400).

FIG. 19 is a graph showing a characteristic curve of the displacement detecting device according to the present invention. When the displacement detecting device is operated at a sampling frequency of 250 Hz, the output of the displacement detecting device according to the displacement is measured. The operating range of the displacement detection device (sensor) is about 0 to 9 mm, and the resolution of the displacement detection device is confirmed to be 0.09 to 0.23 μm (@ 0 to 4 mm) for the +/- 2 mm amplitude based on the reference operation position 2 mm.

20 is a graph showing a curve fitting of a displacement detecting device according to the present invention,

to be.

here, y = output (Count) of the displacement detection device, x = displacement (mm)

21 is a graph showing a sensitivity curve of the displacement detection device according to the present invention.

Sensitivity represents the distance per output change of the displacement detection device.

The output relation of the displacement-displacement detecting device obtained from the result of the curve fitting is as follows.

Here, y = sensor output (Count), x = displacement (mm)

to be.

The sensor sensitivity S (x) according to the distance can be expressed as follows.

는

의 역함수이다.here,

The

Inverse function.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It will be understood that various modifications and changes may be made without departing from the scope of the appended claims.

30: Mount
40: sensor
50: DSP controller
91: Moving Mass
92: Sashige Ban

Claims (7)

As the vibration isolation mount apparatus 400,
An air spring 410 for canceling a load applied at an upper portion thereof; And
And is connected to the lower portion of the load supporting portion 415 of the air spring 410 so as to be vibrated in the MR fluid 430 in accordance with the vibration of the air spring 410, The cage 450,
Lt; / RTI >
The air spring (410)
A top plate 414 connected to an upper end of the side wall 412 through an elastic member 413 and one side connected to the top plate 414 and the other side connected to an upper load 414, And a load supporting portion 415 connected to the plate connecting rod 21,
The vibration damping mount device (400)
A tubular damper housing 421 installed inside the air spring 410 and having a bottom and an opened upper surface;
A MR fluid 430 filled in the damper housing 421;
A cylindrical core 441 fixed to the inner bottom surface 422 of the damper housing 421; And
A coil 442 wound around the core 441,
Further comprising:
The cage 450,
And is connected to a lower portion of the load supporting portion 415 so as to surround the core 441 inside the damper housing 421,
The cage 450,
A membrane 451 formed in parallel with the surface of the MR fluid 430 and moving downward according to a load; And
A cage side surface portion 452 connected to a lower portion of the membrane 451 and having an open bottom,
And,
The cage side surface portion 452,
And which is made of a material that blocks the flow of a magnetic field,
Damping mount device.
delete delete delete delete The method according to claim 1,
The cage side surface portion 452,
Having a plurality of holes 453 through which a magnetic field generated as a current flows in the coil 442
And the vibration-damping mount device. The method according to claim 1,
The membrane (451)
Composed of elastic material
And the vibration-damping mount device.

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