Warning: fopen(111data/log202007080829.log): failed to open stream: No space left on device in /home/pde321/public_html/header.php on line 107

Warning: flock() expects parameter 1 to be resource, boolean given in /home/pde321/public_html/header.php on line 108

Warning: fclose() expects parameter 1 to be resource, boolean given in /home/pde321/public_html/header.php on line 113
Messung des Drehmomentes einer rotierenden Welle mit hoher Auflösung - Dokument EP1398608
 
PatentDe  


Dokumentenidentifikation EP1398608 25.10.2007
EP-Veröffentlichungsnummer 0001398608
Titel Messung des Drehmomentes einer rotierenden Welle mit hoher Auflösung
Anmelder General Electric Co., Schenectady, N.Y., US
Erfinder Delvaux, John McConnell, Greer, South Carolina 29650, US;
Sue, Peter Ping-Liang, Greer, South Carolina 29650, US
Vertreter derzeit kein Vertreter bestellt
DE-Aktenzeichen 60316236
Vertragsstaaten CH, DE, FR, GB, IT, LI
Sprache des Dokument EN
EP-Anmeldetag 29.08.2003
EP-Aktenzeichen 032553869
EP-Offenlegungsdatum 17.03.2004
EP date of grant 12.09.2007
Veröffentlichungstag im Patentblatt 25.10.2007
IPC-Hauptklasse G01L 3/12(2006.01)A, F, I, 20051017, B, H, EP

Beschreibung[en]

The present invention relates to an apparatus for measuring torsional displacement of a rotating shaft.

Various machines, such as a gas turbine and/or a steam turbine, may be used to drive a load such as a power generator. In particular, a gas turbine and/or a steam turbine may be used to rotate a magnet within a stator to generate electric power. The power generator includes a shaft which is connected to the rotating magnet and which itself is connected to a large connecting shaft (also called a load coupling shaft) rotated by one or more turbines. The connecting shaft is typically large and stiff, thereby resulting in very small torsional displacements (strains) when a torque is imposed on the connecting shaft. A measurement of torque transmitted through the connecting shaft is often made to determine the power output of the machine(s) rotating the connecting shaft.

The torque imposed on the connecting shaft has been measured in the past using strain gauges. However, the accuracy of torque measurements provided by strain gauges often does not meet engineering requirements because the uncertainty of such measurements is rather large as compared to the strains measured.

Accordingly, there remains a need in the art to measure torque on a rotating shaft, such as a rotating load coupling shaft for driving a power generator, with a high degree of accuracy. The present invention satisfies this need. For example, the present invention is capable of measuring torque of a rotating shaft within a +/- 0.5% accuracy.

A known digital light probe system, developed by GE Aircraft Engines, has been used for several applications in the past including measuring compressor rotating blade vibratory displacements.

Known systems for determining the torque being transmitted through a rotating shaft are described in US-A-5,979,248 , US-A-4,995,257 , GB-A-2,125,958 , and US-A-5,452,616 . A known apparatus for measuring the vibrations in a rotating shaft is disclosed in EP-A-1,227,325 .

US 4, 148,222 describes an apparatus and method for measuring torsional vibration.

According to the present invention, there is provided an apparatus as defined in appended claim 1.

The processor may determine a torque imposed on the rotatable shaft based upon its torsional displacement. The processor may determine the torsional displacement based on the difference in time between when the first response signal is received by the first probe and when the second response signal is received by the second probe.

The first and second probes may be formed by laser probes and the first and second targets may include a reflective material so that the first transmission signal is a laser light signal and the first response signal is a laser light signal formed from a reflection of the first transmission signal by the first target and the second transmission signal is a laser light signal and the second response signal is a laser light signal formed from a reflection of the second transmission signal by the second target. The first and second targets may be coupled to the rotatable shaft on opposite axial ends thereof. Explanatory examples and embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:

  • FIGURE 1 is a diagram illustrating, inter alia, a cross sectional view of a rotating shaft in a simple cycle configuration whose torque is measured.
  • FIGURE 2A is a diagram illustrating signals received by two different laser light probes from a rotating shaft having no measurable torque imposed thereon.
  • FIGURE 2B is a diagram illustrating signals received by two different laser light probes from a rotating shaft having a measurable torque imposed thereon.
  • FIGURES 3A-3C are diagrams illustrating an exemplary method for calculating torque of a rotating shaft based on its torsional displacement (circumferential twist).
  • FIGURE 4 is a diagram illustrating, inter alia, a cross sectional view of a rotating shaft in a combined cycle configuration whose torque is measured.
  • FIGURE 5 is a perspective view of the combined cycle configuration illustrated in Figure 4 (viewed from the reverse side of Figure 4).
  • FIGURE 6 is a diagram illustrating, inter alia, a cross sectional view of a rotating shaft in a simple cycle configuration whose torque is measured in accordance with an exemplary embodiment of the present invention.
  • FIGURE 7 is a cross sectional view taken from line 7-7 in Figure 6.

Figure 1 illustrates a shaft 20 that serves as a load coupling shaft. Shaft 20 is connected at one axial end 24a to shaft 42 of gas turbine 40 and connected at the other axial end 24b to a rotatable shaft 62 of power generator 60. Accordingly, shaft 20 forms a portion of a simple cycle configuration exemplary embodiment illustrated in Figure 1.

Shaft 20 is rotated by gas turbine machine 40. In turn, the rotational force provided by gas turbine machine 40 is transmitted to rotatable shaft 62 of power generator 60. Rotatable shaft 62 of power generator 60 is connected to a magnet 64 which rotates with rotatable shaft 62 (and hence with shaft 20) within a stator (not shown) of power generator 60 to generate electric power.

Shaft 20 includes a hollow area 22 and one or more passageways 26 leading to hollow area 22. Wires 38 extend through passageways 26 and hollow area 22 to carry signals to and/or from a RF telemetry system 36. RF telemetry system 36 is capable of rotating along with shaft 20 and transmits/receives signals to/from, for example, power generator 60 through wires 38 or wirelessly through a transmitting antenna of the RF telemetry system 36.

A pair of targets 32 and 34 are bonded on an outer surface of shaft 20. Targets 32 and 34 may be mounted on opposite axial ends of shaft 20. For example, as illustrated in Figure 1, targets 32 and 34 are separated along the axial direction by approximately 80 inches. The respective radii of the outer surface on which targets 32 and 34 are bonded are approximately 11 and 22 inches, respectively. While Figure 1 illustrates targets 32 and 34 being bonded on the outer surface of shaft 20 at different radii, targets 32 and 34 could alternatively be mounted on an outer surface of shaft 20 at the same radii. Each of targets 32 and 34 may be formed by a pair of highly reflective tapes which are each capable of intensifying and reflecting a light signal which is incident on the tape. Each of the targets 32 and 34 may be aligned at the same circumferential position or be circumferentially offset from one another.

A pair of low power laser light probes 12 and 14 are positioned at an angle which is perpendicular to shaft 20. Laser light probes 12 and 14 may be made of fiber optic cables for transmitting and receiving laser light signals. The tips of laser light probes 12 and 14 which are closest to shaft 20 are approximately 0.05 inches from the outer surface of shaft 20. Laser light probes 12 and 14 are aligned in the same axial planes as targets 32 and 34, respectively.

Laser light probes 12 and 14 are connected to processor 10. Processor 10, as will be discussed in more detail below, is capable of calculating a torsional displacement (circumferential twist) of rotating shaft 20 based upon measurements taken by laser light probes 12 and 14 and calculating a torque imposed on shaft 20 based on its torsional displacement. Processor 10, may be implemented by, for example, General Electric Aircraft Engine (GEAE) digital light probe system.

Target 33 is bonded on an outer surface of shaft 20 and may be formed by a metal. Like targets 32 and 34, target 33 rotates along with shaft 20. Target 33 rotates underneath probe 13 once per revolution of shaft 20. Probe 13 may be, for example, an eddy current probe which detects the presence of (metal) target 33. A signal from probe 13 is triggered and sent to processor 10 once during every revolution of shaft 20 as target 33 passes underneath and is detected by probe 13. The trigger signal provided from probe 13 enables processor 10 to establish a reference zero timing for signals received by laser probes 12 and 13 in every revolution of shaft 20. Accordingly, a time measured from the reference zero time to the time laser probe 12 or 14 receives a signal is started when probe 13 transmits a trigger signal to processor 10 in every revolution. In cooperation with target 33, probe 13 thus forms a "one per revolution sensor." The operation of probe 13 and target 33 also provide the necessary information to allow processor 10 to calculate the rotational speed of shaft 20. Specifically, the rotational speed of shaft 20 may be determined by &ohgr; = 2 x &pgr; x (1/time difference between two consecutive trigger signals sent from probe 13).

In operation, gas turbine 40 will rotate shaft 20, which will in turn rotate shaft 62 of power generator 60. The rotation of shaft 62 enables magnet 64 to rotate within a stator of power generator 60 to generate electric power.

As shaft 20 rotates, targets 32 and 34 will once pass underneath laser light probes 12 and 14 upon every revolution of shaft 20. The laser light signals transmitted by laser light probes 12 and 14 will be incident on targets 32 and 34, respectively, as those targets 32 and 34 pass underneath probes 12 and 14. Targets 32 and 34 will intensify and reflect the transmitted laser light signals incident on targets 32 and 34. The reflected laser light signals, which effectively form response laser light signals (i.e., laser light signals formed in response to the transmitted laser light signals incident on targets 32, 34) are received by laser light probes 12 and 14 which then send corresponding signals to processor 10. Processor 10 determines and records the precise time at which the laser light signal reflected from target 32 is received by probe 12 and the precise time at which the laser light signal reflected from target 34 is received at probe 14. The difference between the respective reception times of the reflected laser light signals by probes 12 and 14 may then be detected. For example, a difference of time of as small as approximately 10 nanoseconds may be detected.

The difference in time between the laser light signal receptions by probes 12 and 14 will change as different levels of torque is applied to rotating shaft 20. After processor 10 has determined the difference in time, processor 10 can then determine an angular torsional displacement of shaft 20. As an example, the torsional displacement measured in radians may be calculated, assuming the circumferential positions of targets 32 and 34 on shaft 20 are the same (i.e., targets 32 and 34 are circumferentially aligned), by multiplying (&Dgr;t x &ohgr;) where &Dgr;t is the time difference between the receptions of laser light signals by probes 12 and 14 and &ohgr; is the rotational speed of shaft 20. The rotational speed &ohgr; of shaft 20 may be determined from the operation of probe 13 and target 33 as discussed above.

Figures 2A and 2B are diagrams illustrating the reception of laser light response signals received by laser light probes 12 and 14 resulting from laser light signals transmitted from laser light probes 12 and 14 being reflected by targets 32 and 34, respectively, when two different levels of torque are imposed on rotating shaft 20 (again assuming that targets 32 and 34 have the same circumferential position). In particular, Figure 2A is a diagram which illustrates laser light signals received by laser light probes 12 and 14 when no (measurable) torque is imposed on rotating shaft 2. As can be seen from Figure 2A, the times at which the respective laser light signals are received by laser light probes 12 and 14 are simultaneous. Accordingly, there is no torsional displacement on shaft 20 (i.e., shaft 20 has not been twisted) as a result of the rotational force imposed on the shaft 20 since &Dgr;t, the time difference between receptions of laser light signals by laser light probes 12 and 14, is 0 seconds. Of course, if targets 32 and 34 are bonded to shaft 20 at circumferentially offset positions, a time difference which depends at least on the rotational speed of shaft 20 would be expected when there is no torsional displacement of shaft 20.

In contrast to Figure 2A, Figure 2B is a diagram illustrating laser light signals received by laser light probes 12 and 14 when a measurable torque is imposed on shaft 20. In particular, because of the torque imposed on shaft 20, shaft 20 will have a torsional displacement (i.e., circumferential twist). Targets 32 and 34 which were previously circumferentially aligned therefore become circumferentially offset from one another so that the respective laser light signals reflected by targets 32 and 34 are received by laser light probes 12 and 14 at different times. This difference in time &Dgr;t may be multiplied by the rotational speed of the shaft w to calculate the torsional displacement in radians.

As illustrated generally in Figures 3A-3C, processor 10 may then calculate the torque imposed on rotating shaft 20 based on its calculated torsional displacement in a highly accurate manner (e.g., with ± 0.5%). For example, the torque may be calculated from the torsional displacement using a finite element model analysis. Power generated by gas turbine 40 may be determined based on the calculated torque.

In particular, torque on shaft 20 may be calculated from the torsional displacement as follows. If shaft 20 comprises a uniform material at a constant temperature and its cross-sectional area is uniform and constant over its entire length, then torque may be calculated using the closed form solution: &tgr; = &thgr; ( G ) j L

where T = torque on shaft, &thgr; = torsional displacement in radians (angle change measured by probes 12, 14 and calculated by processor 10), G = shear modulus of the material of shaft 20 (available in engineering handbooks), j = polar moment of inertia and L = axial distance between probes 12 and 14. The polar moment of inertia (j) is the inherent stiffness of shaft 20 and can be calculated by j = ( &pgr; ) R 4 2 for a solid circular cross section where R = radius of shaft 20.

The torque calculation becomes more complex to precisely determine if any one or more of the following occur:

  • (1)Shear modulus (G) changes along the length

    and/or radial direction (e.g., due to temperature changes of the shaft material or use of a different material).
  • (2)If the cross-sectional area of shaft 20 is not uniform (e.g., keyway notch)
  • (3)If the cross-sectional area is not constant along the length of shaft 20.

Items (2) and (3) affect the polar moment of inertia (j) calculation. While a combination of shaft design features (items (1) and (3) above) make it virtually impossible to accurately convert torsional displacement to torque using hand calculations (see Figure 3A), Finite Element Analysis (FEA) can be utilized to accurately to make this calculation with great precision. Specifically, a Finite Element Model (FEM) is created that captures the shaft geometry, material properties, and boundary conditions. A necessary boundary condition is an arbitrary torque load applied parallel to the shaft centerline. The FEA is performed on the FEM and the result is a distribution of torsional displacement along shaft 20 as can be seen in Figure 3B. The amount of torsional displacement between the two axially spaced probes 12 and 14 is readily available by FEA post processing. This is accomplished by taking the arbitrary torque value used in the FEM and dividing it by the calculated torsional displacement value determined from processor 10. This is the constant that relates torsional displacement to torque as shown in Figure 3C. Thus, the torque carried by shaft 20 in operation can be calculated by taking the torsional displacement determined by processor 10 and multiplying by the FEA calculated constant.

While shaft 20 illustrated in the example of Figure 1 is rotated by a gas turbine 40, those skilled in the art will appreciate that shaft 20 may alternatively be rotated by another machine such as a steam turbine, nuclear power generator or internal combustion engine. Moreover, although shaft 20 transmits the rotational force exerted on it from gas turbine 40 to rotate a magnet 64 in power generator 60, those skilled in the art will appreciate that shaft 20 can be alternatively connected to drive other loads. For example, shaft 20, once rotated by a machine such as turbine 40, can be used to drive other loads such as rotating a propeller on a vehicle.

Figures 4-5 illustrate another example. Reference numbers corresponding to parts previously described will remain the same. Only the differences from previous examples (will be discussed in detail. While Figure 1 illustrates shaft 20 as part of a simple cycle configuration, Figures 4-5 illustrate shaft 20 as part of a combined cycle configuration. Specifically, shaft 20 illustrated in Figures 4-5 is rotated by gas turbine 40 while steam turbine 50 imposes a rotational force on shaft 62 of power generator 60. Axial end 24a of shaft 20 is connected to shaft 42 of gas turbine 40 and axial end 24b of shaft 20 is connected to shaft 52 of steam turbine 50. Gas turbine 40 rotates shaft 42 to rotate shaft 20 and, in turn, shaft 20 rotates shaft 52 of steam turbine 50. Thus, the torque imposed on shaft 20 by gas turbine 40 is transmitted to shaft 52 which then imposes a torque on shaft 62. Shaft 62 is thus subject to the combined rotational forces from steam turbine 50 and gas turbine 40. Magnet 64 of power generator 60 thus rotates as a result of rotational forces provided by steam turbine 50 and gas turbine 40.

As discussed in the example of the Figure 1, as shaft 20 is rotated by gas turbine 40, laser light signals transmitted from laser light probes 12 and 14 are reflected by targets 32 and 34, respectively, as they revolve and pass underneath probes 12 and 14. The laser light signals reflected from targets 32 and 34 are received by laser light probes 12 and 14 and their respective times of arrival measured. Processor 10 then calculates the difference in the time at which laser light signals are received by laser light probes 12 and 14 to determine a torsional displacement and then determines a torque imposed on shaft 20 based upon its torsional displacement. Power generated by gas turbine 40 can be calculated from the determination of torque.

Figures 6-7 illustrate an embodiment of the present invention. Again, reference numbers corresponding to parts previously described will remain the same. Only the differences will be discussed in detail. Figures 6-7 illustrate multiple targets passing underneath each of light probes 12, 14. Specifically, two (or more) targets 32, 32a pass underneath light probe 12 and two (or more) targets 34, 34a pass underneath light probe 14 upon rotation of shaft 20.

As shaft 20 twists when it is loaded, targets 32 and 34 will be displaced from one another as discussed above. These targets 32 and 34 will also be displaced from one another if shaft 20 vibrates. The displacement from shaft vibration can be measured through the use of additional targets 32a and 34b. By assessing the time of arrival of at least one of the sets of targets 32 and 32a (or 34 and 34a) within one revolution of shaft 20 and comparing it to the expected time of arrival based on the actual distance between the targets 32 and 32a and the rotational speed of shaft 20, the displacement from vibration can be calculated. For example, if targets 32 and 32a are circumferentially offset from one another by 180° (see Fig. 7), the respective times of arrival of signals detected by probe 12 is expected to be one-half of the time required for one complete rotation. The time for a complete rotation may be determined through the operation of probe 13 and target 33 as discussed above. The displacement of shaft 20 due to its vibration may then be determined by the difference between the expected time difference and the actual time difference that respective response signals from targets 32 and 32a are detected by probe 12 and/or the difference between the expected time difference and the actual time difference that respective response signals from targets 34 and 34a are detected by laser light probe 14. The total torsional displacement may thus be determined by adding the displacement caused by the vibration and the load displacement (i.e., the torsional displacement caused by the rotational force imposed on shaft 20). Accordingly, by bonding additional targets 32a and/or 34a to shaft 20 and detecting response signals therefrom utilizing laser probes 12 and/or 14, a correctional value may be determined for the torsional displacement resulting from the rotational force imposed on shaft 20. Accuracy in the torsional displacement measurement may therefore be enhanced.

While Figs. 6-7 illustrate adding additional targets 32a, 34a onto shaft 20 as part of a simple cycle configuration, those skilled in the art will appreciate that targets 32a, 34a may also be added to a shaft 20 as part of a combined cycle configuration as illustrated in Figs. 4-5.


Anspruch[de]
Vorrichtung, umfassend: eine drehbare Achse (20), mindestens ein erstes Ziel (32), das mit der drehbaren Achse (20) verbunden ist, so dass es sich mit dieser zusammen dreht; mindestens ein zweites Ziel (34), das mit der drehbaren Achse (20) verbunden ist, so dass es sich mit dieser zusammen dreht; eine erste Sonde (12) zur Übertragung eines ersten Übertragungssignals zu dem ersten Ziel (32) und zum Empfang eines ersten Antwortsignals von dem ersten Ziel (32); eine zweite Sonde (14) zur Übertragung eines zweiten Übertragungssignals an das zweite Ziel (34) und zum Empfang eines zweiten Antwortsignals von dem zweiten Ziel (34); und einen Prozessor (10), welcher funktional mit der ersten und zweiten Sonde (12, 14) verbunden ist und zur Bestimmung einer Drehmomentverschiebung der Achse (20) auf der Grundlage von mindestens dem ersten und zweiten Antwortsignal dient, die jeweils von der ersten und zweiten Sonde (12, 24) empfangen wurden, gekennzeichnet durch: ein weiteres erstes Ziel (32a), das mit der drehbaren Achse (20) verbunden ist, so dass es sich mit dieser zusammen dreht; wobei die erste Sonde (12) so angepasst ist, dass sie das erste Übertragungssignal an das weitere erste Ziel (32a) überträgt und ein weiteres erstes Antwortsignal von dem weiteren ersten Ziel (32a) erhält; und wobei der Prozessor (10) so angepasst ist, dass er eine Vibrationsverlagerung der Achse (20) auf der Grundlage der Differenz zwischen der erwarteten Zeitdifferenz und der tatsächlichen Zeitdifferenz zwischen dem ersten Antwortsignal und dem weiteren ersten Antwortsignal bestimmt, welche von der ersten Sonde (12) empfangen wurden, und dass er einen korrigierten Wert für die Drehmomentverlagerung der Achse bestimmt. Vorrichtung gemäß Anspruch 1, dadurch gekennzeichnet, dass der Prozessor (10) so angepasst ist, dass er das Drehmoment, welchem die drehbare Achse (20) ausgesetzt ist, auf der Grundlage der Drehmomentverlagerung der Achse (20) bestimmt. Vorrichtung gemäß Anspruch 1, dadurch gekennzeichnet, dass der Prozessor (10) so angepasst ist, das er eine Drehmomentverlagerung auf der Grundlage der Zeitdifferenz zwischen dem Zeitpunkt des Empfangs des ersten Antwortsignals durch die erste Sonde (12) und dem Zeitpunkt des Empfangs des zweiten Antwortsignals durch die zweite Sonde (14) bestimmt. Vorrichtung gemäß Anspruch 1, ferner einen Stromgenerator (60) umfassend, zu dem ein Magnet (64) gehört, welcher mit der drehbaren Achse (20) verbunden ist, so dass es sich mit dieser zusammen dreht. Vorrichtung gemäß Anspruch 1, ferner mindestens entweder eine Gasturbine (40) oder eine Dampfturbine (50) zum Zwecke der Drehung der drehbaren Achse (20) umfassend. Vorrichtung gemäß Anspruch 1, dadurch gekennzeichnet, dass die erste und die zweite Sonde (12, 14) Lasersonden sind und das erste und das zweite Ziel (32, 34) ein reflektierendes Material enthalten, so dass das erste Übertragungssignal ein Laserlichtsignal ist und das erste Antwortsignal ein Laserlichtsignal ist, das durch eine Reflexion des ersten Übertragungssignals durch das erste Ziel (32) entsteht, und so dass das zweite Übertragungssignal ein Laserlichtsignal ist und das zweite Antwortsignal ein Laserlichtsignal ist, das durch eine Reflexion des zweiten Übertragungssignals durch das zweite Ziel (34) entsteht. Vorrichtung gemäß Anspruch 1, dadurch gekennzeichnet, dass das erste und zweite Ziel (32, 34) an entgegen gesetzten axialen Endabschnitten (24a, 24b) der drehbaren Achse (20) mit derselben verbunden sind.
Anspruch[en]
An apparatus comprising: a rotatable shaft (20); at least one first target (32) coupled on the rotatable shaft (20) so as to rotate therewith; at least one second target (34) coupled on the rotatable shaft (20) so as to rotate therewith; a first probe (12) for transmitting a first transmission signal to the first target (32) and receiving a first response signal from the first target (32); a second probe (14) for transmitting a second transmission signal to the second target (34) and receiving a second response signal from the second target (34); and a processor (10) operatively coupled to the first and second probes (12, 14) for determining a torsional displacement of the shaft (20) based at least on the first and second response signals received by the first and second probes (12, 14), respectively; characterised by: another first target (32a) coupled on the rotatable shaft (20) so as to rotate therewith; wherein the first probe (12) is adapted to transmit the first transmission signal to the another first target (32a) and to receive another first response signal from the another first target (32a); and

wherein the processor (10) is adapted to determine a vibration displacement of the shaft (20) based on the difference between the expected time difference and the actual time difference of the first response signal and the another first response signal received by the first probe (12), and to determine a corrected value for the torsional displacement of the shaft.
The apparatus as in claim 1, wherein the processor (10) is adapted to determine a torque imposed on the rotatable shaft (20) based upon the torsional displacement of the shaft (20). The apparatus as in claim 1, wherein the processor (10) is adapted to determine the torsional displacement based on the difference in time between when the first response signal is received by the first probe (12) and when the second response signal is received by the second probe (14). The apparatus as in claim 1, further comprising a power generator (60) which includes a magnet (64) which is coupled to the rotatable shaft (20) to rotate therewith. The apparatus as in claim 1, further comprising at least one of a gas turbine (40) and a steam turbine (50) for rotating the rotatable shaft (20). The apparatus as in claim 1, wherein the first and second probes (12, 14) are laser probes and the first and second targets (32, 34) include a reflective material so that the first transmission signal is a laser light signal and the first response signal is a laser light signal formed from a reflection of the first transmission signal by the first target (32), and the second transmission signal is a laser light signal and the second response signal is a laser light signal formed from a reflection of the second transmission signal by the second target (34). The apparatus as in claim 1, wherein the first and second targets (32, 34) are coupled to the rotatable shaft (20) on opposite axial ends (24a, 24b) thereof.
Anspruch[fr]
Appareil comprenant : un arbre rotatif (20) ; au moins une première cible (32) couplée sur l'arbre rotatif (20) afin de pivoter avec celui-ci ; au moins une deuxième cible (34) couplée sur l'arbre rotatif (20) afin de pivoter avec celui-ci ; une première sonde (12) pour émettre un premier signal d'émission à la première cible (32) et recevoir un premier signal de réponse de la première cible (32) ; une deuxième sonde (14) pour émettre un deuxième signal d'émission à la deuxième cible (34) et recevoir un deuxième signal de réponse de la deuxième cible (34) ; et un processeur (10) couplé de manière opérationnelle à la première et deuxième sonde (12, 14) afin de déterminer un déplacement par torsion de l'arbre (20) au moins sur la base d'un premier et d'un deuxième signal de réponse reçu par la première et deuxième sonde (12, 14), respectivement ; caractérisé par : une autre première cible (32a) couplée sur l'arbre rotatif (20) afin de pivoter avec celui-ci ; dans lequel la première sonde (12) est adaptée pour émettre le premier signal d'émission à cette autre première cible (32a) et pour recevoir cet autre premier signal de réponse à partir de cette autre première cible (32a) ; et dans lequel le processeur (10) est adapté pour déterminer un déplacement de vibration de l'arbre (20) sur la base de la différence entre la différence de temps attendue et la différence de temps réelle du premier signal de réponse et cet autre premier signal de réponse reçu par la première sonde (12), et pour déterminer une valeur corrigée pour le déplacement par torsion de l'arbre. Appareil selon la revendication 1, dans lequel le processeur (10) est adapté pour déterminer un couple imposé sur l'arbre rotatif (20) sur la base du déplacement par torsion de l'arbre (20). Appareil selon la revendication 1, dans lequel le processeur (10) est adapté pour déterminer le déplacement par torsion sur la base de la différence de temps entre le moment où le premier signal de réponse est reçu par la première sonde (12) et le moment où le deuxième signal de réponse est reçu par la deuxième sonde (14). Appareil selon la revendication 1, comprenant en outre un générateur d'énergie (60) qui comprend un aimant (64) qui est couplé à l'arbre rotatif (20) pour pivoter avec celui-ci. Appareil selon la revendication 1, comprenant en outre au moins une parmi une turbine à gaz (40) et une turbine à vapeur (50) pour faire pivoter l'arbre rotatif (20). Appareil selon la revendication 1, dans lequel la première et la deuxième sonde (12, 14) sont des sondes laser et la première et deuxième cible (32, 34) comprennent un matériau réfléchissant afin que le premier signal de transmission soit un signal de lumière laser et que le premier signal de réponse soit un signal de lumière laser formé à partir d'une réflexion du premier signal d'émission par la première cible (32), et le deuxième signal d'émission est un signal de lumière laser et le deuxième signal de réponse est un signal de lumière laser formé à partir d'une réflexion du deuxième signal d'émission par la deuxième cible (34). Appareil selon la revendication 1, dans lequel la première et la , deuxième cible (32, 34) sont couplées à l'arbre rotatif (20) sur les extrémités axiales opposées (24a, 24b) de celui-ci.






IPC
A Täglicher Lebensbedarf
B Arbeitsverfahren; Transportieren
C Chemie; Hüttenwesen
D Textilien; Papier
E Bauwesen; Erdbohren; Bergbau
F Maschinenbau; Beleuchtung; Heizung; Waffen; Sprengen
G Physik
H Elektrotechnik

Anmelder
Datum

Patentrecherche

Patent Zeichnungen (PDF)

Copyright © 2008 Patent-De Alle Rechte vorbehalten. eMail: info@patent-de.com