CN2077128U - Laser doppler instantaneous velocimeter - Google Patents
Laser doppler instantaneous velocimeter Download PDFInfo
- Publication number
- CN2077128U CN2077128U CN 89219248 CN89219248U CN2077128U CN 2077128 U CN2077128 U CN 2077128U CN 89219248 CN89219248 CN 89219248 CN 89219248 U CN89219248 U CN 89219248U CN 2077128 U CN2077128 U CN 2077128U
- Authority
- CN
- China
- Prior art keywords
- utility
- model
- laser doppler
- instantaneous
- speed
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Images
Landscapes
- Optical Radar Systems And Details Thereof (AREA)
Abstract
The utility model relates to a laser Doppler instantaneous velocimeter, which belongs to a device which is used for testing rotating machinery instantaneous rotational speed. The utility model is composed of a laser Doppler sensor system, an electronic system, a microcomputer and a display and printing system, wherein, the electronic system is composed of a preposition amplifier, a filter, a frequency selective amplifier and a correlation detector. The utility model tests the instantaneous rotation speed by utilizing the laser Doppler frequency shift signals of particle-scattering light of the surface of a rotating body, and the sampling interval is 10+[-6]S level. A tested object needs no additional device, and the speed testing adopts a non-contact type. The utility model is in particular suitable for the fields of spaceflight, automatic control, high precision detection, micro and special motor, etc.
Description
The utility model belongs to the device of test rotation class machinery transient speed, is specially adapted to the test of the stability of small and special electric machine etc.
The instrument of the class of test rotation at present mechanical separator speed is a lot, but generally can only measure the certain hour mean speed of (a second or shorter time) at interval, as light electric tachometer, stroboscope and light pulse knotmeter etc.Improving on the instantaneity, general available grating dish knotmeter and Laser Doppler Velocimeter, but adopt grating dish velocity measuring technique that the grating dish will be installed on measurand, this has certain influence to the precision of measuring; And adopt the laser Dppler veloicty measurement technology, and because it is a non-cpntact measurement, measurand need not added any device again, therefore the instantaneity that raising is tested the speed is very suitable.The Laser Doppler Velocimeter of seeing at present (as Sweden DANTEC company product), its time interval of choosing is 10
-3The s magnitude, this still is far from being enough for this high-performance test request of the speed stability that resembles small and special electric machine.
It is 10 that the purpose of this utility model will obtain the time interval exactly
-6The instantaneous speed measuring device of s magnitude is so that have the rotation system of high stability requirement to give effectively test and supervision to rotating speed.
For above purpose, the utility model has designed relevant electronic system, and it is made up of prime amplifier, filtering, frequency-selecting amplifier and correlation detector, uses related detecting method, by the cycle of laser-Doppler frequency displacement is correctly measured, thereby record the transient speed of measurand.
Because the time interval of sampling is shorter, rotating speed is just more near true value, and the test of speed stability has just been had assurance.This device can obtain hundreds of in rotary body rotates a week (time interval of each data reaches 10 to several thousand rotary speed datas
-6The s magnitude), the rotating speed of measuring at last can show on computer screen, and printablely goes out relevant data.
Accompanying drawing 1 is a general structure block scheme of the present utility model.
Accompanying drawing 2 is schematic diagrams of prime amplifier.
Accompanying drawing 3 is schematic diagrams of correlation detector.
Below in conjunction with an embodiment of the present utility model, give again to specify.
From H
e-N
eLaser instrument 1 emitted laser, be divided into the two laser that intensity is identical, meet coherent condition with beam splitter 3, the a branch of bundle to convergent lens 4 with another through catoptron 2 reflection back makes on its measurement point that focuses on tested rotary body surface, the doppler shifted signal of the scattered light that produces by the motion particle on rotary body surface, give photoelectricity training increasing pipe 7 by receiving light path and focus lamp 5, aperture 6, thereby finish by the conversion reception (above 1-7 promptly forms the laser-Doppler sensor-based system) of light signal to electric signal.
The generation of doppler shifted signal can be illustrated that two restraint in the intersection of laser by the interference fringe model, the striped that two relevant light beams produce, and its spacing is:
s＝ (λ)/(2sin（α／2）)
λ is used Wavelength of Laser in the formula, and α is the angle of two relevant light beams.When the motion particle on rotary body surface with speed
During by the striate region, if
Direction and the angle between the normal of two beam angle α bisectors be β, then particle can be subjected to the modulation of light intensity, its frequency is:
f
D＝ (vcosβ)/(s) ＝ (2v)/(λ) cosβsin（α／2）
Differential doppler frequency that Here it is.
When the frequency f of knowing signal
D, just can converse the linear velocity v of measured point on the rotary body, thereby calculate the rotating speed of rotary body.
The utility model and the general method of measured frequency, and the employing related detecting method carries out period T
DMensuration because f
D=1/T
DThereby, measure the rotating speed of rotary body equally.This method also can make the time interval of sampling reach 10
-6The s magnitude.
For this reason, the spy is provided with electronic system, and it comprises prime amplifier 8, wave filter 9, frequency-selecting amplifier 10 and correlation detector 11.
Because the distribution of particles on rotary body to be measured surface is variant, roughness is also inconsistent, be subjected to low frequency signal surface roughness modulation, that amplitude is very big again (base is low) so exist, and the frequency shift signal that we will take is modulated on this low frequency signal.Make this Doppler signal can become the electric signal of being accepted by microsystem, now use prime amplifier (Fig. 2) to be amplified from the faint doppler shifted signal of the continuous random amplitude of photomultiplier output, and it is carried out processing such as shaping, the logical frequency-selecting of band, remove its substrate, yet give coherent detection again.
In the correlation detector (Fig. 3), BG
1And BG
2By two triode 3DGA6 and R
1(130 Ω), R
2(6.5K Ω), R
3(56K Ω), R
4(75 Ω), R
3(12K Ω), R
6(3.5K Ω), R
7(8K Ω), R
8(2.4K Ω) and C
3(0.22 μ f), C
4(0.22 μ f), C
5(0.22 μ f), C
6(0.033 μ f) forms post amplifier.C
1(100 μ f), C
2(100 μ f), C
12(100 μ f) makes power filter and uses.IC
1And IC
2By two integrated package MC4066 and L
1(0.8mH) C
7(0.032 μ f), L
2(0.7mH), C
8(0.022 μ f), L
3(0.6mH) C
8(0.012 μ f), L
4(0.5mH) C
10(0.0047 μ f), L
5(0.3mH) C
11(3000pf) form frequency-selecting amplifier, because this knotmeter mensuration range of speeds is wide, in order to obtain the high mensuration of precision, the gamut rotating speed is divided into five grades of measurements, be respectively 500K, 600K, 700K, 800K and 1MHz, each shares K by above-mentioned five groups of inductance capacitance coils
1Be the speed change-over switch.BG
3By triode 3DG12C and C
13(0.056 μ f), R
9(56K Ω), R
10(12K Ω), R
11(5.6K Ω), R
12(2K Ω) and C
14(0.056 μ f) forms shaping and voltage amplifier circuit.D
1(2CW21G), C
16(47 μ f), R
16(1.3K Ω) forms mu balanced circuit, C
15(47 μ f) does filtering and uses.IC
3By integrated package MC14574 and W
1(10K Ω), R
13(10K Ω), R
14(5K Ω), W
2(10K Ω), R
17(10K Ω), R
18(2K Ω) and R
15(2.7K Ω) forms the two-way voltage comparator, and it will be by BG
3The signal in any cycle in the Doppler signal of shaping utilizes threshold values resistance W
1And W
2Carry out the comparison of low valve valve and high threshold values, thereby draw two comparison waveforms of same signal waveform.If these two comparison waveforms belong to same Doppler signal and get, its cycle necessarily equates; If these two comparison waveforms are not to be Doppler signal, but noise or weak signal, its cycle necessarily differs greatly, and because of the accidental interference that occurs of noise or weak signal system, does not have the coherence in continuous coverage.Output just is the sampled signal of a high threshold values and low valve valve at last.
Doppler signal after treatment by interface I/O12, is defeated by microcomputer 13.Interface circuit is the hardware cell of forming with the TTL integrated circuit, and it is mainly finished data acquisition and accepts control signal.Carry out after data computing gathers through microcomputer, just show on display 14 or be printed as written information by printer 15,16 is the software input unit.
Claims (1)
1, a kind of rotation class machinery transient speed proving installation, by the laser-Doppler sensor-based system, prime amplifier, wave filter, frequency-selecting amplifier, microcomputer and demonstration, print system are formed, and it is characterized in that being connected with behind frequency selector correlation detector.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 89219248 CN2077128U (en) | 1989-12-09 | 1989-12-09 | Laser doppler instantaneous velocimeter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 89219248 CN2077128U (en) | 1989-12-09 | 1989-12-09 | Laser doppler instantaneous velocimeter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2077128U true CN2077128U (en) | 1991-05-15 |
Family
ID=4874151
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 89219248 Withdrawn CN2077128U (en) | 1989-12-09 | 1989-12-09 | Laser doppler instantaneous velocimeter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2077128U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104614544A (en) * | 2014-09-10 | 2015-05-13 | 中国航空工业集团公司北京长城计量测试技术研究所 | Differential type laser-measuring-impact method and device based on partial period demodulation |
| CN105699691A (en) * | 2016-03-15 | 2016-06-22 | 重庆工商大学 | Oil initial speed-based LDV in-oil suspended particle instantaneous speed processing method |
-
1989
- 1989-12-09 CN CN 89219248 patent/CN2077128U/en not_active Withdrawn
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104614544A (en) * | 2014-09-10 | 2015-05-13 | 中国航空工业集团公司北京长城计量测试技术研究所 | Differential type laser-measuring-impact method and device based on partial period demodulation |
| CN105699691A (en) * | 2016-03-15 | 2016-06-22 | 重庆工商大学 | Oil initial speed-based LDV in-oil suspended particle instantaneous speed processing method |
| CN105699691B (en) * | 2016-03-15 | 2020-05-15 | 重庆工商大学 | Method for processing instantaneous velocity of suspended particles in LDV oil based on initial velocity of oil |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106595728A (en) | Rotor axial displacement, rotating speed and inclination angle radial integrated measurement method | |
| CN101639337B (en) | Real-time measurement method of dynamic radius and dynamic misalignment angle of precision centrifuge and device thereof | |
| Sweeney et al. | Gear transmission error measurement using phase demodulation | |
| CN201615907U (en) | Low angular rate detection device for rotating stage | |
| CN201072422Y (en) | Train speed sensor | |
| CN105203794A (en) | Electric generator rotation speed measuring system and method | |
| CN104698217B (en) | Contactless differential difference correlation instantaneous velocity method for sensing | |
| CN102252652B (en) | Method for measuring incident angle of laser by multi-beam laser heterodyne quadratic harmonic method | |
| CN111854917B (en) | Non-contact torsional vibration measurement method based on machine vision | |
| CN2077128U (en) | Laser doppler instantaneous velocimeter | |
| CN109520547A (en) | High-low temperature precision detection device and detection method for photoelectric encoder | |
| CN102221356B (en) | Device and method for measuring laser incident angle by sinusoidally modulating multi-beam laser heterodyne secondary harmonics with Doppler galvanometer | |
| CN205808544U (en) | A kind of fibre optic hydrophone acceleration sensitivity test system | |
| CN112230012A (en) | Instantaneous fluctuation rotating speed measuring device and method | |
| CN209927277U (en) | Torsional vibration signal generator containing time-varying inter-harmonic | |
| CN113324879B (en) | Method for measuring anisotropic rotational movement particles | |
| CN102253075B (en) | Device and method for measuring metal linear expansion coefficient based on multi-beam laser heterodyne second harmonic | |
| CN2861966Y (en) | Lazar inertial reference type fast road cross-section tester | |
| CN1024593C (en) | measurement method for phase and integer of phase of heterodyne interferometer signal processing | |
| CN112798025A (en) | Method for improving OFDR measurement spatial resolution and OFDR system | |
| CN109489707A (en) | Incremental photoelectric encoder testing machine and testing method | |
| CN109085374A (en) | The multiple spot speed measuring device and its speed-measuring method for slow-speed of revolution system based on kinect | |
| CN113607409B (en) | Testing system and method for gear | |
| CN113639625B (en) | Dynamic testing system for seat ring clearance of large-scale rotating machinery | |
| Gogoasa et al. | An extrinsic optical fibre speed sensor based on cross correlation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |