TWI356160B - System for measuring and monitoring vibration - Google Patents

Description

13.56160. The change of the revision game on September 30, 100. 6. Description of the invention: [Technical field of the invention] [0001] The present invention relates to a measurement and monitoring system, and more particularly to a vibration measurement and monitoring system. [Prior Art] [〇〇〇2] Vibration measurement and monitoring covers a wide range of fields such as mechanics, electronics, construction, and geology. It also has a large application background in the study of the properties of materials. Specially, it is miniaturized with 3C products. Quantitative development trend, precision molds and precision machining technology for manufacturing 3C products require high-speed spindles for fast cutting with low cutting capacity, while the friction or eccentricity of the bearings of the spindle itself will cause vibration of the speed-precision spindle, which will affect the precision machining. Precision. In addition, these machines including idle rotating shafts have inherent resonant frequencies. When the operating frequency of the rotating parts of the machine matches the natural frequency of the machine, it will increase the vibration of the machine and rotating parts, and even cause malfunctions, resulting in possible damage. This includes insufficient machining accuracy, mechanical breakage, and even personal injury. In order to improve the machining accuracy of the machine, reduce the damage of the shooting machine and damage to the human body, it is necessary to make a measurement or monitoring of the vibration of the rotating parts of the machine, so that the machine can be closed or suspended when it exceeds the acceptable vibration limit or the resonance point. The machine, or a control device, performs different actions when the machine exceeds different set limits, allowing the vibration to return to acceptable limits. This ensures the accuracy of the processed product and avoids working near the resonance point, thus avoiding damage or avoiding further damage. [] Objective, the commonly used vibration measuring device uses the magnitude of the electromotive force generated by measuring the movement of the coil in the magnetic field to determine the structure of the vibration. Since the magnetic field 094130340 Form No. A0101 Page 3 of 17 page 1003358718-0 丄356160 100 years .09月.30日修jggg· The uneven distribution of the body is difficult to eliminate, and some equipment or instruments will also generate some magnetic field distribution during the working process. Therefore, the frequency band for measuring vibration is not wide enough. The dynamic range of the amplitude is small, especially In the measurement of weak vibration signals, the sensitivity is low, which makes the application field very limited. [0004] The structure of a pickup device for measuring the vibration acceleration measurement of a bearing, as shown in the sixth figure, is used for picking up The vibration of the bearing 2 is composed of an accelerometer 21, a force measuring spring 22, a transmission rod 23, a base 24, an end cover 25, a sleeve 26 and the like. The transmission rod 21 is in contact with the non-rotating portion of the bearing 26, and is vibrating. During the measurement, the inner ring of the bearing 2〇 is driven to rotate by the drive shaft (not shown), and the outer ring of the 20 outer ring is kept stationary by the surface load. The vibration is transmitted to the accelerometer 21 through the transmission rod and converted into a charge amount*Electrical_out, and (10) the vibration is analyzed. [0005] The above measurement methods are all contact measurement, which needs to be in contact with the measured object to effectively sense the measured object. The vibration state, therefore, it is not possible to directly measure the vibration of a high-speed rotating object such as a high-precision rotating shaft of precision machining. [Invention] [0006] In the above content, it is necessary to provide a kind of non-contact vibration measurement and monitoring. [0007] quantity or monitoring, which includes: a laser light, a vibration, a system of light sources, a laser source system, a laser beam system, a laser beam system, a laser beam system, a field measuring system, and a light sensing system. The laser is in a secret state, and the light sense is set relative to the upper shot system to sense the light intensity change of the light sensing system emitted by the above-mentioned lightning (four), and the above-mentioned Light between the laser light source system and the light sensing system · 094130340 Measure 1003358718-0 Form number Α 0101 Page 4 / Π page system receiving light 1 1.56160

100 years, September, and 30th, according to the positive replacement page, the current signal outputted by the system is measured and the position of the rotating shaft is calculated by the conversion process. Then, combined with the measurement of the time, the vibration structure of the measured object is calculated and processed. [0008] Compared with the prior art, the vibration measuring and monitoring system uses a beam of laser light to be shielded by an object to generate a change in light intensity, and the change of the current signal outputted by the light sensor is measured by the light sensor, that is, The amount of vibration of the object can be calculated in conjunction with the measurement of time. It adopts optical non-contact measurement, and the rotating axis of the measured object does not touch the measuring system at all times, which can prevent the surface of the rotating object from being damaged due to friction, and can measure the vibration of high-speed moving objects. Moreover, it does not utilize a conventional piezoelectric sensor, which is resistant to electromagnetic interference and strong radiation, has a wide test frequency, and has high precision, and the application field is greatly expanded. [0009] In addition, since the beam propagation speed is fast, its response to the vibration change is fast, and the vibration frequency bandwidth which can be measured can be measured. [0010] Again, since the intensity range of the intensity that can be detected by the light sensing system is large, the dynamic range of the measurable amplitude is large, and the light intensity change caused by the vibration signal or even the weak vibration signal can be received by the light receiving element. Therefore, the sensitivity is high. [Embodiment] Referring to the first and second figures, the vibration measuring and monitoring system 1 of the preferred embodiment of the present invention is used to measure or monitor the vibration structure of a rotating shaft 10, and the vibration measuring and monitoring system 1 The invention comprises: a laser light source system 11, a light sensing system 12 and a processing system (not shown) and a result output device (not shown). The laser source system 11 is for emitting a parallel laser beam 13 which is composed of a laser source 111 and a plurality of lenses 112, which are typically gas lasers, such as krypton-rhenium lasers, which emit Laser beam 094130340 Form No. A0101 Page 5 of Π page. 1003358718-0 1356160 On September 30, 30, the shuttle is a Gaussian beam. The light sensing system 12 is disposed opposite to the laser light source system 11 and senses the light intensity distribution incident on the surface thereof by the light sensor 121 and converts it into a current signal output. The processing system can be a computer system or a microprocessor, and the current signal outputted by the light sensing system 12 is converted to calculate the position of the rotating shaft (described later), and combined with the measurement of the time, the vibration structure of the rotating shaft is calculated. The output device is configured to output the vibration structure of the measured rotating shaft, which may be a display interface or a printing device, or an automatic alarm system, and the normal vibration range is set in the processing system, when the measured object vibrates beyond the setting range. That is, the operator is alerted by the automatic alarm system or automatically adjusted by the control device. The stomach [0012] is operated such that the measured rotating shaft 10 is vertically and the light beam 13 is placed between the laser light source system 11 and the light sensing system 12, the vibration measuring and monitoring system 1 is turned on, and the laser light source system 11 emits a laser. The beam 13 is partially blocked by the axis of rotation 10. When the rotating shaft 10 rotates, the rotating shaft 10 vibrates in the radial direction thereof, so that the portion of the light beam 13 blocked by the rotating shaft 10 changes, so that the light intensity incident on the light sensing system 12 changes, and the light sensing system 12 changes. The change signal of the light intensity is converted into a current signal to the processing system _, and the processing system processes the position of the rotating shaft, and measures the vibration structure of the rotating shaft in combination with the time and outputs it through the output device. [0013] It can be understood that, if not required, the result output device can be omitted, and the control device directly controls the operation of the machine according to the measurement or monitoring result. In addition, the vibration measuring and monitoring system of the present invention can also be used for other non-rotating axes. The vibration is measured and monitored. [0014] Please refer to the third to fifth figures, the vibration measurement and monitoring method is applied to the principle of the laser knife edge method, and the following is the realization of the vibration measurement and monitoring method 094130340 Form No. A0101 Page 6 of 17 1003358718-0 13.56160 100^.09^ 30 a The principle depends on the basic transverse electromagnetic mode oscillation, and the resulting beam intensity is a Gaussian spatial distribution. The laser beam 13 is called a Gaussian beam. The electric field distribution, as shown in the third figure, if expressed in a mathematical model, can be written as: [0015] -x, exp(-W{zy W%)] (a) [0016] exp. (b) (Eq -l) # [0017] ---(c) Fine PhM;: /:> * f. ·, [0018] The first term (a) after the equal sign is an amplitude factor (Ampiitude factor) Indicates the relationship between the amplitude r and the change; the second term (b) is the phase change of the optical wave along the axial direction z; the third term (c) is the phase change of the optical wave along the radial direction (Radial) r relationship. Wherein ' r = (x2 + y2) 0 · 5, W 〇 is the waist waist ra-dius, EQ is the electric field strength at the waist, .3⁄4 is the wavelength, and j is the imaginary symbol. On this plane, the radius of curvature of the wave front (R) is (, which is a plane and the diameters of the beams are the smallest (z) and R (z) are the distances from the waist of the beam. The radius of the spot on the plane of z (Spot size or Beam size) and the radius of curvature of the wavefront, and the wave number k=.u=., if the origin (z = 0) is set at the waist, 1003358718-0 094130340 Form No. A0101 Page 7 / Total 17 Page 1356160 [0022] [0022] 100 years. September 30th 30th

= (Eq-2} Guanlan: ' Σ^, J ^)=0+( 413⁄4 wear: ;(Eq-3) In the above formula,

iJ:^ is defined as Rayleigh's face, and the distance at the waist (Waist) is (2=^), and the spot area is exactly twice the waist area (Waist area). The wave radius of curvature R is the smallest. When the beam travels by a distance Z>>ZR, the RSiz, WK1, Gaussian beam approximates a light emitted by a point source located at the waist, and its divergence angle can be approximated as follows: Bu: 4__1"·响_ 4) It can be seen that W〇 and 4 determine all the properties of the Gaussian beam. Since the electric field of the light wave changes very quickly, it is processed in the manner of light intensity in the detection. In general, the detection system detects the intensity distribution of light rather than the amplitude. Therefore, the intensity distribution of light is obtained by multiplying (Eq-l) and its common consumption complex number, as shown in the Cartesian coordinate table as follows:

[0025] [0025] [0026]

094130340 Form NumberΑ0101 Page 8 of 17 1003358718-0 [0027]

1356160 > I

[0028] : 2 fetch, eight HO-eight)] ~~W- 100 years 09i · 30th press positive replacement page (Eq-5) _ "Zhong X. ‘ Υ. The center of the beam; the intensity of the light at the center of the beam; the radius of the WS beam (spot-Size or beam size), which is the radius of the Gaussian beam, defined as: the intensity of the light from the center point to the sides - 2 w to S e (about 〇. 1353 times), one half of the distance between two points

[0〇3〇] Please refer to the first and fourth figures at the same time, assuming that the direction of the scan is the x-axis, the portion of the laser beam 13 that is not obscured by the axis of rotation ίο, the light intensity received by the sensor 121 The signal is: [0031] [0032] .. (Eq-6)

[0033] %2(χ^:χύ)ΐ W^: :ik [0034] where Xa is the position of the axis of the rotation axis 10 at the x coordinate axis. The light intensity distribution curve of the entire laser beam region can be obtained by the above formula (Eq-6) as shown in the fifth (A) diagram. Now consider the corresponding difference between the two positions, that is, the corresponding light intensity signal difference is: 094130340 Form No. A0101 Page 9 / Total 17 · [Page ~: '1003358718-0 [0036] [0037] 1356160 (Eq- 7) The result of the above formula (Eq-7) is equivalent to the integration of the light intensity of the portion of the slit region in the fifth (B) diagram. [0038] If S(xa) is divided by the signal S(〇〇) caused by the total energy of the laser; that is, all the laser beams 13 are not interrupted (the total energy signal of xa 4, then S(xa) can be made The normalization process produces a dimensionless light intensity signal that resists changes in the measured signal due to environmental deflection: [0039]

(Eq-8)

[0040] With the mathematical model described above, the light beam between the light source and the light sensor is blocked by the measured rotating shaft, causing a change in the light intensity of the surface of the sensor, and the light intensity change output is detected by the light sensor. The current signal is converted by the ADC (analog-digital converter 'Analog-Digital CQnvei^e]^ to the position of the shaft by computer or microprocessor via Eq-7, Eq-8, combined with the measurement of the time axis. The vibration amount of the rotating shaft can be obtained. [0041] In summary, the present invention has indeed met the requirements of the invention patent, and the patent application is filed according to law. However, the above description is only a preferred embodiment of the present invention, and those skilled in the art are familiar with the present invention. Equivalent modifications or changes made by the person in the spirit of the invention shall be included in the following patent application. [Simplified illustration] [0042] The first figure is preferably the vibration measuring and monitoring system of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS [0043] 094130340 The second figure is a laser light source system of the vibration measuring and monitoring system of the present invention. Form No. A0101 Page 10 of 17 Page 1003358Ή8-0 13,56160 1:00年.09月30 Japanese nuclear BRIEF DESCRIPTION OF THE DRAWINGS [0044] The third figure is a vibration suppression and monitoring system of the present invention. FIG. 4 is a field distribution characteristic diagram of a Gaussian laser beam; 0046] The fifth (Α) graph is a light intensity distribution curve of the Gaussian laser light; [0047] The fifth (Β) graph is a schematic diagram of the light intensity integral region of the Gaussian laser beam; [0048] Schematic diagram of vibration measurement. • [Main component symbol description] [0049] Vibration measurement and monitoring system: 1 [0050] Rotary axis: 10 [0051] Laser source system: 11 [0052] Laser source: 111 [0053] Complex lens :112 φ [0054] Light sensing system: 12 [0055] Light sensor: 121 [0056] Light beam: 13 094130340 Form number Α 0101 Page 11 / Total 17 pages 1003358718-0

Claims (1)

1356160 _.__ 100 years. September 30th 30th Child's Correction & Page 7 Scope of Application: 1. A vibration measurement and monitoring system for measuring or monitoring the vibration of a measured object, including: a laser light source system capable of emitting a laser beam; a light sensing system disposed opposite the laser system for sensing a laser emitted by the laser system The change in light intensity transmitted by the beam to the light sensing system, where the light intensity changes to, where dx X represents the coordinate axis, xa represents the position of the object under the X coordinate axis, χΟ is the center of the beam, W is the beam section radius, and the above-mentioned object is partially blocked by the beam between the laser source system and the light sensing system. A processing system receives the signal outputted by the light sensing system, calculates the position of the measured object through conversion processing, and combines the measurement of the time to calculate and process the vibration structure of the measured object. 2. The vibration measuring and monitoring system of claim 1, wherein the vibration measuring and monitoring system further comprises a result output device. 3. The vibration measuring and monitoring system of claim 1, wherein the laser light source system is composed of a laser light source and a plurality of lenses. 4. The vibration measuring and monitoring system of claim 1, wherein the laser source is a gas laser. 5. The vibration measuring and monitoring system of claim 1 or 4, wherein the laser source is a 氦-氖 laser. 6. The vibration measuring and monitoring system of claim 1, wherein the laser beam is a parallel beam. 094130340 Form No. A0101 Page 12 of 17 1003358718-0 13.56160 100 years. September 30th, 30th revised replacement page 7. The vibration measuring and monitoring system according to claim 1, wherein the laser beam It is a Gaussian beam. 8. The vibration measuring and monitoring system of claim 1, wherein the light sensing system comprises a light sensor. 9. The vibration measuring and monitoring system of claim 8, wherein the photo sensor is a photosensitive diode. The vibration measuring and monitoring system of claim 1, wherein the processing system is a computer system. 11. The vibration measuring and monitoring system of claim 1, wherein the processing system is a microprocessor. 12. The vibration measuring and monitoring system of claim 2, wherein the result output device is a display interface. 13. The vibration measuring and monitoring system of claim 2, wherein the result output device is a printing device. 14. The vibration measuring and monitoring system of claim 2, wherein the result output device is an alarm system. 094130340 Form No. Α0101 Page 13 of 17 1003358718-0