CN103439526A - Optical fiber type speed sensor for rail transit - Google Patents
Optical fiber type speed sensor for rail transit Download PDFInfo
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- CN103439526A CN103439526A CN2013103781802A CN201310378180A CN103439526A CN 103439526 A CN103439526 A CN 103439526A CN 2013103781802 A CN2013103781802 A CN 2013103781802A CN 201310378180 A CN201310378180 A CN 201310378180A CN 103439526 A CN103439526 A CN 103439526A
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Abstract
The invention discloses an optical fiber type speed sensor for rail transit. The optical fiber type speed sensor comprises a rotary speed transmitting mechanism, an optical grating sheet, an optical fiber speed measurement module, an optical cable, a circuit box, a light source, an optical detector, a measurement circuit and a signal electric cable, wherein the optical grating sheet is installed on a shaft of the rotary speed transmitting mechanism, the optical fiber speed measurement module is installed inside the rotary speed transmitting mechanism and matched with the optical grating sheet to be capable of enabling light between two optical fibers to be coupled and enabling an optical grating hole of the optical grating sheet to be located in an optical fiber coupling channel to modulate on-off of the optical fiber coupling channel, the optical cable is used for connecting the optical fiber speed measurement module with the circuit box, can transmit light emitted by the light source in the circuit box to the optical fiber speed measurement module and can also transmit the modulated light in the optical fiber speed measurement module to the optical detector in the circuit box, the circuit box is used for containing the light source, the optical detector and the measurement circuit, the measurement circuit is used for driving the light source and converting a signal output by the optical detector into a square wave pulse width signal, and then the square wave pulse width signal is output through the signal electric cable.
Description
Technical field
The present invention relates to a kind of optical fiber type speed pickup.
Background technology
The track traffic industry need to be measured the speed of locomotive, and measurement result is the key control parameter of the systems such as Train Control, brake, train supervision.This parameter measurement is inaccurate, gently causes train operation that the phenomenons such as late occur, heavy may cause the accidents such as derailed because of excessive velocities.
Measuring speed of locomotive is divided into absolute velocity and measures and tachometric survey.Absolute velocity is measured the general non-contacting sensors such as radar type, optical profile type that adopt and is measured the relatively speed of face of locomotive, and tachometric survey generally adopts the rotating speed at the positions such as sensor measurement motor, gear, axletree such as Hall-type, magneto-electric and photo-electric.
Photoelectric tachometric transducer is installed on all kinds locomotive shaft-end, for locomotive provides travelling speed and direction of motion, is the important component part of locomotive safety running.This sensor input shaft is connected with tested wheel shaft, tested wheel shaft drives the rotation of sensor input shaft, and tested wheel shaft rotating speed equates with the input shaft rotating speed, utilizes the photoelectric effect of optical-electric module, produce electric impulse signal proportional to vehicle wheel rotational speed, thereby realize the function tested the speed.That this sensor has is simple in structure, reliability is high, the measuring accuracy advantages of higher, therefore is widely used.
But photoelectric tachometric transducer adopts at present extensively light activated element or photoelectric encoder to carry out transmitting and receiving of signal, utilize lenticular lenses to carry out the output electric pulse signal to the blocking of light path, locomotive control calculates rotating speed according to the frequency of output pulse.There is following shortcoming in such sensor:
1, the axle head of electric locomotive high-tension electricity occurs because of imperfect earth sometimes, thereby causing whole sensor internal is a high voltage environment, particularly metal grating sheet surface also can be with high voltage, and due to close together between the light activated element of electro-optical pickoff or photoelectric encoder and metal grating sheet, can be punctured by high-tension electricity, burn out sensor; Although the part photoelectric sensor improves the voltage withstand class of sensor by the distance increased between light activated element and lenticular lenses, but still can't eradicate hidden danger.
2, the output signal of electro-optical pickoff, by cable transmission, can be subject to the impact of electromagnetic interference (EMI) in transmitting procedure, thus the phenomenons such as generation mistake pulse.
3, due to the restriction of sensor internal volume, electro-optical pickoff output signal channel number is less, also only have at most in the market the sensor of six passages, the client can only be installed more sensor additional when the more signalling channel of needs like this, has increased system bulk and cost.
4, the phase differential in photoelectric sensor is to control by manual setting, comparatively wastes time and energy, and has research that two paths of signals is integrated in an optical module, but, due to the reasons such as reflection of physical construction inside, has interference phenomenon between two paths of signals.
Summary of the invention
Technical matters to be solved by this invention is to overcome the above-mentioned deficiency of existing electro-optical pickoff and kind of a kind of track traffic optical fiber type speed pickup is provided, and can more safely measure.
The present invention solves the problems of the technologies described above adopted technical scheme:
Track traffic optical fiber type speed pickup, it is characterized in that: comprise the rotating speed transmission mechanism, lenticular lenses, the optical fiber speed measuring module, optical fiber, circuit box, light source, photo-detector, metering circuit, signal cable, lenticular lenses is arranged on the axle of rotating speed transmission mechanism, the optical fiber speed measuring module is arranged on the inside of rotating speed transmission mechanism, and match with lenticular lenses, can make two light between optical fiber be coupled, and the grating hole that makes lenticular lenses is on the coupling fiber passage, break-make to coupling channel is modulated, optical fiber is used for connecting optical fiber speed measuring module and circuit box, the light that light source in circuit box can be sent is delivered in the optical fiber speed measuring module, also the modulated light in optic module can be passed to the photo-detector in circuit box, circuit box is used for holding light source, photo-detector and metering circuit, metering circuit is used for driving light source, and convert the signal of photo-detector output to the square wave pulse width signal, then by signal cable, export.
Compared with prior art, the invention has the advantages that: 1,, because optical fiber is nonconductor, can not be electrically shocked and wear, and the circuit part of sensor is placed on the far-end away from measure field, high-tension impact can be subject to, the high pressure resistant problem of photoelectric sensor can be solved.On this series products, use first optical fiber to be used as measuring unit and signal transduction pathway.
2, be light signal due to what transmit in optical fiber, be not subject to the impact of electromagnetic interference (EMI) fully, can solve the electromagnetic interference problem of photoelectric sensor.
3, the transmission range due to optical fiber is far away, and in measure field, without metering circuit, the volume of optical fiber is also comparatively fine, can in a sensor, realize more measuring passage.
4,, because optical fiber is comparatively very thin, the angle of its emergent light also within certain scope, therefore be easy to realize the isolation between two ways of optical signals, can solve the problem that phase differential between two paths of signals needs manual setting.
The accompanying drawing explanation
Fig. 1 is the structural representation of embodiment of the present invention track traffic with the optical fiber type speed pickup.
Fig. 2 is the structural representation of embodiment of the present invention optical fiber speed measuring module one embodiment.
Fig. 3 is the structural representation of another embodiment of embodiment of the present invention optical fiber speed measuring module.
Fig. 4 is the structural representation of the another embodiment of embodiment of the present invention optical fiber speed measuring module.
Fig. 5 is the structural representation of the another embodiment of embodiment of the present invention optical fiber speed measuring module.
Fig. 6 is the structural representation of the another embodiment of embodiment of the present invention optical fiber speed measuring module.
Fig. 7 is the structural representation of the another embodiment of embodiment of the present invention optical fiber speed measuring module.
Fig. 8 is the structural representation of the another embodiment of embodiment of the present invention optical fiber speed measuring module.
Embodiment
Below in conjunction with accompanying drawing embodiment, the invention will be further described.
As shown in Figure 1, track traffic optical fiber type speed pickup, comprise rotating speed transmission mechanism 1, lenticular lenses 2, optical fiber speed measuring module 3, optical cable 4, circuit box 5, light source 6, photo-detector 7, metering circuit 8, signal cable 9.
Rotating speed transmission mechanism 1 is arranged on the axle head of locomotive, can stablize, accurately the axletree rotating speed be passed to lenticular lenses 2, and its reliable in structure, anti-pollution, shock and vibration, and can effectively prevent that the pollutants such as greasy dirt, dust from entering into lenticular lenses 2 and optical fiber speed measuring module 3.
Lenticular lenses 2 is arranged on the axle of rotating speed transmission mechanism 1, can be modulated the break-make of light path.
Optical cable 4 is used for connecting optic module 3 and circuit box 5, and the light that light source in circuit box 6 can be sent is delivered in optic module 3, also the modulated light in optic module can be passed to the photo-detector 7 in circuit box.Optical cable 4 has certain intensity, can protect optical fiber wherein not to be pulled off.
Circuit box 5 is used for holding light source 6, photo-detector 7 and metering circuit 8, and it has higher degree of protection, can shock resistance, vibration, can prevent that environmental contaminants from entering its inside, also has the effect of electromagnetic screen.
Track traffic has three kinds of selections with the optical fiber in the optical fiber type speed pickup.
It is to use silica fibre that the first is selected, and the advantage of this optical fiber is that light transmission is good, optical property stable, life-span length can be not aging, non-combustible, and shortcoming is that minimum bending radius is larger, and quality is also comparatively fragile, under the strong vibration environment, may rupture; Making sensor with it needs larger volume to carry out receiving optical fiber, and need to carry out special protection to prevent the fracture of optical fiber to optical fiber.
It is to use plastic optical fiber that the second is selected, and the advantage of this optical fiber is that tension, anti-folding, anti-vibration performance are good, and minimum bending radius is little, and shortcoming is that long-term use meeting is aging, and in 10 ~ 20 years life-spans, light transmission also decreases, and the material of optical fiber is flammable; Make sensor with it, can meet the demands on the life-span, the sheath of optical cable must adopt halogen-free low-smoke flame retardant material, could meet the request for utilization of the railway system.
The third selection is the silica fibre that uses the plastics covering, and it has advantages of above two kinds of optical fiber, but it still has bending radius greatly and the poor shortcoming of anti-vibration performance.Comparatively speaking, plastic optical fiber is the optimal selection of optical fibre velocity sensor.
The optical fiber speed measuring module is of paramount importance sensing unit in sensor of the present invention, and it makes the light in optical fiber be modulated together with lenticular lenses, and the optical fiber speed measuring module has multiple implementation.
The first implementation shows as Fig. 2, and in figure, launching fiber 31, receives optical fiber 32, unthreaded hole sheet 33, grating 34.Launching fiber 31 is plastic optical fiber or silica fibre, and it is connected with the optical cable of Fig. 1, and the light that light source sends emits from launching fiber, by entering into after unthreaded hole sheet 33 and lenticular lenses 34, receives optical fiber 32.Launching fiber 31 and reception optical fiber 32 are also interchangeable, and 32 as launching fiber, and 31 as receiving optical fiber.The effect of unthreaded hole sheet 33 is diameters of controlling launching fiber 31 and receiving the light beam of propagating between optical fiber 32, makes it to be no more than the width in grid hole above lenticular lenses 34, thereby guarantees that light beam can only pass a grid hole at most.This implementation principle is simple, lower to the positioning accuracy request of optical fiber, and it is comparatively easy to implement, but, because the minimum bending radius of optical fiber is more much larger than electric wire, the sensor bulk of therefore making is also larger.
The second implementation is shown as Fig. 3.In figure, launching fiber 31, receive optical fiber 32, unthreaded hole sheet 33, grating 34, right-angle prism 35.Launching fiber 31 is plastic optical fiber or silica fibre, and it is connected with the optical cable in Fig. 1, and the light that light source sends emits from launching fiber, by unthreaded hole sheet 33 with lenticular lenses 34 is rear is reflected by right-angle prism 35, then enters into and receives optical fiber 32.Similar in the implementation one of the effect of optical fiber 31 and 32, unthreaded hole sheet 33 and optical fiber speed measuring module.The effect of right-angle prism 35 is to make 90 ° of the direction of propagation deflections of light, and it also can replace with the optical element of 90 ° of other any direction of propagation deflections that can make light.This implementation has reduced below the optical fiber speed measuring module requirement to installing space, but larger to side and top requirements of installation space, the installation accuracy of optical fiber 32 and right-angle prism 35 is required also highlyer simultaneously, and the cost of module is also higher than mode one.
The third implementation is shown as Fig. 4.In figure, launching fiber 31, receive optical fiber 32, unthreaded hole sheet 33, grating 34, right-angle prism 35.Launching fiber 31 is plastic optical fiber or silica fibre, it is connected with the optical cable in Fig. 1, the light that light source sends emits from launching fiber, by 90 ° of first right-angle prism 35 deflections, then by unthreaded hole sheet 33 and lenticular lenses 34, by 90 ° of second right-angle prism, 35 deflections, finally enter into and receive optical fiber 32 afterwards.Similar in the effect of optical fiber 31 and 32, unthreaded hole sheet 33, right-angle prism 35 and the implementation two of optical fiber speed measuring module.Right-angle prism 35 also can replace with the optical element of 90 ° of other any direction of propagation deflections that can make light.This implementation has reduced above the optical fiber speed measuring module and the following requirement to installing space, but the requirements of installation space to side is larger, simultaneously also higher to the installation accuracy requirement of optical fiber 31, optical fiber 32 and right-angle prism 35, the cost of module is also higher than mode two.
The 4th kind of implementation shown as Fig. 5.In figure, launching fiber 31, receive optical fiber 32, unthreaded hole sheet 33, grating 34, Dove prism 35.Launching fiber 31 is plastic optical fiber or silica fibre, it is connected with the optical cable in Fig. 1, and the light that light source sends emits from launching fiber, by unthreaded hole sheet 33 and lenticular lenses 34, then by 180 ° of Dove prism 35 deflections, finally enter into and receive optical fiber 32.Similar in the implementation two of the effect of optical fiber 31 and 32, unthreaded hole sheet 33 and optical fiber speed measuring module.The effect of Dove prism 35 is to make 180 ° of the direction of propagation deflections of light, and it also can replace with the optical element of 180 ° of other any direction of propagation deflections that can make light.This implementation has reduced optical fiber speed measuring module side and the following requirement to installing space, but larger to top dress space requirement, and simultaneously also higher to the installation accuracy requirement of optical fiber 32 and Dove prism 35, the cost of module and mode three are similar.
The optical fiber speed measuring module can be realized distinguishing of rotation direction, also can realize the velocity survey of a plurality of passages, its principle is to be integrated with the multi-path light passage to realize multi-channel measurement in same module, be 90 ° by the phase differential of setting output signal between every two optical channels simultaneously, so just can differentiate rotation direction according to the front and back of signal output waveform.The implementation of this hyperchannel velocity survey and the implementation of direction identification and photoelectric tachometric transducer are similar, but photoelectric tachometric transducer can only be realized two passages at most in a module, and in four-way or six channel sensors, the phase differential between each passage can only be regulated by people's craft like this.And the volume ratio circuit of optical fiber is little a lot, and the transmission light between two adjacent optical fiber can not interfere with each other, and therefore is easy to realize more multichannel velocity survey in an optical fiber speed measuring module.
The existence of prism is arranged in the implementation two, three, four of optical fiber speed measuring module, and they can increase the cost of system.Three kinds of multichannel implementations are provided in the present invention, and the first is the polygon prism mode, and in this mode, each optical channel has a set of independently prism system, like this system realize that cost and difficulty of processing are all higher, but disturb between each passage; The second is single prism mode, and in this mode, two or more passages share a set of prism system, like this system realize cost and difficulty of processing lower, but may have certain interference phenomenon between each passage; The third is annular prism mode, and in this mode, all passages share the prism system of a collar-shaped, and such system realizes that cost is minimum, but may have interference phenomenon between each passage.The implementation three of optical fiber speed measuring module of below only take describes the first and the second hyperchannel implementation respectively as example, and the implementation four of optical fiber speed measuring module of take describes the third hyperchannel implementation as example.The implementation two, three, four that it is pointed out that the optical fiber speed measuring module all can be used these three kinds of modes to realize the hyperchannel velocity survey.
The first implementation of hyperchannel speed measuring module is as Fig. 6 institute.In figure, launching fiber 31, receive optical fiber 32, prism 35.Launching fiber and reception optical fiber are corresponding one by one, and the position of launching fiber and reception optical fiber can exchange.A pair of launching fiber and reception optical fiber form a passage, and the light path between them is continued by independent a set of prism system.In the implementation two of optical fiber speed measuring module, prism system is a right-angle prism; In the implementation three of optical fiber speed measuring module, prism system is two right-angle prisms; In the implementation four of optical fiber speed measuring module, prism system is a Dove prism.
The second implementation of hyperchannel speed measuring module is shown as Fig. 7.In figure, launching fiber 31, receive optical fiber 32, prism 35.Launching fiber and reception optical fiber are corresponding one by one, and the position of launching fiber and reception optical fiber can exchange.A pair of launching fiber and reception optical fiber form a passage.The light path of a plurality of passages continues and all realizes by same set of prism system, and the width of this prism system is very wide, can cover a plurality of passages.In the implementation two of optical fiber speed measuring module, prism system is a right-angle prism; In the implementation three of optical fiber speed measuring module, prism system is two right-angle prisms; In the implementation four of optical fiber speed measuring module, prism system is a Dove prism.Adopt the speed measuring module port number of this mode can not be too much, otherwise lenticular lenses can't be modulated the break-make of the light path of all passages.
The third implementation of hyperchannel speed measuring module is shown as Fig. 8.In figure, launching fiber 31, receive optical fiber 32, prism 35.Launching fiber and reception optical fiber are corresponding one by one, and the position of launching fiber and reception optical fiber can exchange.A pair of launching fiber and reception optical fiber form a passage, and the light path of all passages is all continued by the prism system of same set of annular.In the implementation two of optical fiber speed measuring module, the right-angle prism that prism system is an annular; In the implementation three of optical fiber speed measuring module, the right-angle prism that prism system is two annulars; In the implementation four of optical fiber speed measuring module, the Dove prism that prism system is an annular.The annular prism can use a whole annulus, also can use eccentric circular ring.Adopt this mode can be in sensor integrated a lot of passages, it is fixed that theoretic largest passages number is come by the size in the size of optical fiber, grating hole.
Claims (7)
1. track traffic optical fiber type speed pickup, it is characterized in that: comprise the rotating speed transmission mechanism, lenticular lenses, the optical fiber speed measuring module, optical fiber, circuit box, light source, photo-detector, metering circuit, signal cable, lenticular lenses is arranged on the axle of rotating speed transmission mechanism, the optical fiber speed measuring module is arranged on the inside of rotating speed transmission mechanism, and match with lenticular lenses, can make two light between optical fiber be coupled, and the grating hole that makes lenticular lenses is on the coupling fiber passage, break-make to coupling channel is modulated, optical fiber is used for connecting optical fiber speed measuring module and circuit box, the light that light source in circuit box can be sent is delivered in the optical fiber speed measuring module, also the modulated light in optic module can be passed to the photo-detector in circuit box, circuit box is used for holding light source, photo-detector and metering circuit, metering circuit is used for driving light source, and convert the signal of photo-detector output to the square wave pulse width signal, then by signal cable, export.
2. track traffic as claimed in claim 1 optical fiber type speed pickup, is characterized in that: the silica fibre that described optical fiber is silica fibre or plastic optical fiber or plastics covering.
3. track traffic as claimed in claim 1 optical fiber type speed pickup, it is characterized in that: described optical fiber speed measuring module comprises launching fiber, receives optical fiber, unthreaded hole sheet, grating, launching fiber is connected with optical cable, the light that light source sends emits from launching fiber, by entering into after unthreaded hole sheet and lenticular lenses, receives optical fiber.
4. track traffic as claimed in claim 1 optical fiber type speed pickup, it is characterized in that: described optical fiber speed measuring module comprises launching fiber, receives optical fiber, unthreaded hole sheet, grating, right-angle prism, launching fiber is connected with optical cable, the light that light source sends emits from launching fiber, by being reflected by right-angle prism after unthreaded hole sheet and lenticular lenses, then enter into and receive optical fiber.
5. track traffic as claimed in claim 1 optical fiber type speed pickup, it is characterized in that: described optical fiber speed measuring module comprises launching fiber, receives optical fiber, unthreaded hole sheet, grating, right-angle prism, launching fiber is connected with optical cable, the light that light source sends emits from launching fiber, by 90 ° of first right-angle prism deflections, then by unthreaded hole sheet and lenticular lenses, afterwards by 90 ° of second right-angle prism deflections, finally enter into and receive optical fiber.
6. track traffic as claimed in claim 1 optical fiber type speed pickup, it is characterized in that: described optical fiber speed measuring module comprises launching fiber, receives optical fiber, unthreaded hole sheet, grating, Dove prism, launching fiber is connected with optical cable, the light that described light source sends emits from launching fiber, by unthreaded hole sheet and lenticular lenses, then by 180 ° of Dove prism deflections, finally enter into and receive optical fiber.
7. track traffic as claimed in claim 1 optical fiber type speed pickup, it is characterized in that: described optical fiber speed measuring module comprises launching fiber, receives optical fiber, prism, launching fiber is connected with optical cable, launching fiber and reception optical fiber are corresponding one by one, a pair of launching fiber and reception optical fiber form a passage, and the light path of a plurality of passages continues and all realizes by prism.
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| CN2013103781802A CN103439526A (en) | 2013-08-28 | 2013-08-28 | Optical fiber type speed sensor for rail transit |
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| CN2013103781802A CN103439526A (en) | 2013-08-28 | 2013-08-28 | Optical fiber type speed sensor for rail transit |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104360096A (en) * | 2014-12-08 | 2015-02-18 | 丹东华信测控技术有限公司 | Speed measuring device capable of utilizing optical fiber transmission |
| CN105403726A (en) * | 2015-12-17 | 2016-03-16 | 滁州市博创电气有限公司 | Pulse velocity measurement module |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5463458A (en) * | 1993-12-16 | 1995-10-31 | General Electric Company | Optical sensor for duct fan discharge mach numbers |
| US6400137B1 (en) * | 1998-09-03 | 2002-06-04 | Itt Manufacturing Enterprises, Inc. | Optical fiber with crimp and for sensing wheel rotation |
| CN202102003U (en) * | 2011-05-24 | 2012-01-04 | 长沙南车电气设备有限公司 | High-speed anti-interference speed detector |
-
2013
- 2013-08-28 CN CN2013103781802A patent/CN103439526A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5463458A (en) * | 1993-12-16 | 1995-10-31 | General Electric Company | Optical sensor for duct fan discharge mach numbers |
| US6400137B1 (en) * | 1998-09-03 | 2002-06-04 | Itt Manufacturing Enterprises, Inc. | Optical fiber with crimp and for sensing wheel rotation |
| CN202102003U (en) * | 2011-05-24 | 2012-01-04 | 长沙南车电气设备有限公司 | High-speed anti-interference speed detector |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104360096A (en) * | 2014-12-08 | 2015-02-18 | 丹东华信测控技术有限公司 | Speed measuring device capable of utilizing optical fiber transmission |
| CN105403726A (en) * | 2015-12-17 | 2016-03-16 | 滁州市博创电气有限公司 | Pulse velocity measurement module |
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Application publication date: 20131211 |