JP2000283891A - Device for measuring rotation component of rotation axis and method for its measurement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prolong the life of a drive source and improve efficiency by calculating the true rotational speed or the torsion vibration component of a rotation axis based on an actual rotational speed at a plurality of locations that have been measured by a rotational speed measurement means. SOLUTION: The device is provided with a rotational speed measurement means 2 and a rotational component operation means 20. The rotational speed measurement means 2 is composed of a first measurement part 3 for calculating a first actual rotational speed V1(t) at a first measurement point L1 that has been set to the rotational axis S based on a first period T1 required for rotating a rotational axis S at a specific angle, and a second measurement part 4 for calculating a second actual rotational sped V2 at a second measurement point L2 based on a second period T2 for rotating rotational axis S at a specific angle at the second measurement point L2 of the rotational axis S separated from the first measurement point L1. The rotational component operation means 20 calculates a true rotational speed V(t) and a torsion vibration component y(t) based on the first actual rotational speed V1 and the second actual rotational speed V2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary shaft rotation component measuring apparatus and a rotary shaft rotation component measuring method applied to measure various rotary components of a rotary shaft provided in various drive sources and the like.

[0002]

2. Description of the Related Art In recent years, an inverter motor controlled by an inverter at a variable speed can obtain a large torque at the time of starting or low-speed operation, and has good follow-up performance with respect to rotation fluctuation, load fluctuation, and the like. Widely used as a driving source. In addition, it goes without saying that internal combustion engines such as diesel engines, gas turbines, and the like have been widely used as drive sources in various fields. On the other hand, the rotating shafts provided for these various driving sources are:
It is made of an elastic body having a mass distribution and forms a vibration system having infinite degrees of freedom. Therefore, when any torque fluctuation acts on the rotating shaft, so-called torsional vibration occurs on the rotating shaft. In this case, when the torque fluctuation frequency and the torsional natural frequency of the rotating shaft match, a resonance phenomenon occurs, and torsional vibration is excited.

[0003]

As described above, in various types of driving sources that rotationally drive the rotating shaft, it is inevitable that torsional vibration is generated on the rotating shaft. However, when torsional vibration of the rotating shaft is excited during operation of the drive source,
A large torsional stress is generated on the rotating shaft. And the generated large torsional stress promotes the fatigue of the rotating shaft,
It may cause cracks and damage. In addition, when torsional vibration occurs on the rotating shaft, the rotating speed directly measured from the rotating shaft (hereinafter, referred to as “actual rotating speed”) includes a net rotating speed excluding the effect of torsion (hereinafter, referred to as “true rotating speed”). )
, And a torsional vibration component are included, and so-called rotational speed unevenness appears on the outer surface of the rotary shaft at different rotational speeds (rotational speeds) at two points separated from each other in the axial direction. Then, the torsional vibration generated as described above and the rotational speed unevenness caused by the torsion vibration cause a reduction in the efficiency and control efficiency of various driving sources.

That is, taking an inverter motor as an example, a torque vector control method is generally adopted for an inverter motor, in which a load variation is calculated from a power supply voltage and the power supply voltage is controlled to be constant based on the calculated load variation. ing. Also, measure the actual rotation speed of the motor rotation shaft,
Speed feedback control for controlling the power supply voltage while comparing with the speed command signal is complementarily employed. In an inverter motor controlled in this manner, torque fluctuation occurs on the rotating shaft due to large waveform distortion in the motor power supply.

[0005] Once a torsional vibration occurs due to a torque fluctuation on the motor rotating shaft, a fluctuation proportional to the torsional vibration occurs on the motor power supply side, and such fluctuation is generated by an automatic voltage regulator (AVR). ) Is superimposed on the torque feedback control signal. Further, since the actual rotation speed of the motor rotation shaft includes a torsional vibration component, the torsional vibration component is also superimposed on the speed feedback control signal. When the torsional vibration component superimposed on the various control signals is larger than the initial torque fluctuation component of the inverter, the torsional vibration is further excited, and the rotating shaft is in a self-excited vibration state.

For example, in a diesel engine,
It measures the actual rotation speed (rotation speed) of the rotating shaft (one end of the crankshaft or the connecting shaft, etc.) on the engine or load side, and controls the fuel injection amount, injection timing, etc. while comparing it with the speed command signal. Is the current situation. However, for example, 2
In the case of a cycle-diesel engine, the torque fluctuation is multiplied by (the number of revolutions of the rotating shaft × the number of cylinders), so that the rotating shaft (crankshaft) generates torsional vibration and the actual rotation measured directly from the rotating shaft. The velocity also includes a torsional vibration component. For this reason, even if the diesel engine is controlled based on the actual rotation speed, the fuel injection amount and the injection timing are not actually appropriate, and as a result, the efficiency of the diesel engine is reduced. Will be.

In any case, various driving sources monitor the fatigue state of the rotating shaft, and prevent torsional vibration caused by cracks, damages, etc., so that torsional vibration is selected from the rotating components of the rotating shaft. Extracting components is extremely important. In addition, in order to efficiently perform feedback control of various drive sources, it is necessary to exclude the torsional vibration component from the control signal or to exclude the torsional vibration component from the obtained actual rotational speed to calculate the true rotational speed. Very important.
However, at present, there is no means for easily and accurately obtaining a rotational component such as a true rotational speed and a torsional vibration component.

Accordingly, the present invention is useful for monitoring the fatigue of a rotating shaft provided in various driving sources and the like, controlling driving, and the like.
It is an object of the present invention to provide a rotating shaft rotation component measuring device and a rotating shaft rotation component measuring method that contribute to prolonging the life of a drive source, improving efficiency, and the like.

[0009]

According to a first aspect of the present invention, there is provided a rotary shaft rotation component measuring apparatus for measuring various rotary components of a rotary shaft driven to rotate. The rotation speed measuring means for measuring the actual rotation speed at a plurality of locations of the rotating shaft, and the real rotation speed and the torsional vibration component of the rotating shaft based on the actual rotation speeds at the plurality of locations measured by the rotation speed measuring means. And a rotation component calculating means for calculating at least one of them.

In the case of using the rotation component measuring device for a rotating shaft, the rotating speed measuring means arranged for the rotating shaft to be measured to be rotated is provided with actual rotating speeds at a plurality of positions (at least two places) of the rotating shaft. That is, the actual rotation speed at the location is measured. That is, for example, the rotation speed measuring unit may calculate the actual rotation speed (first actual rotation speed) V1 (t) at a certain point (first measurement point) on the rotation axis and another point on the rotation axis (second measurement point). Actual rotation speed (point 2)
The actual rotation speed) V2 (t) is measured.

Here, if V1 (t) and V2 (t) are found, if the true rotational speed is V (t) and the torsional vibration component is y (t), V1 (t) = V ( t) + φ1 · y (t) (1) A simultaneous equation of V2 (t) = V (t) + φ2 · y (t) (2) can be established. Note that φ1 and φ2 are torsional vibration modes at the first measurement point and the second measurement point, and are numerical values that can be actually measured or calculated in advance for various types of rotation axes.

In this rotational component measuring device, the rotational component calculating means calculates the above equations (1) and (2) from the actual rotational speeds V1 (t) and V2 (t) obtained by the rotational speed measuring means. And the torsional vibration component y (t), which is the solution of the simultaneous equations consisting of Thus, according to the rotation component measurement device of the rotation shaft, it is possible to easily and accurately obtain at least one of the true rotation speed and the torsional vibration component among the various rotation components of the rotation shaft. Therefore, by using the torsional vibration component obtained by the rotational component measurement device, the fatigue state of the rotating shaft provided in various driving sources and the like is monitored, or the true rotation speed and the torsional vibration component obtained are used. Thus, it is possible to appropriately control the driving of the rotating shaft. As a result, by using this rotation component measuring device, it is possible to extremely easily achieve a longer life of the drive source, an improvement in efficiency, and the like.

The rotation speed measurement means measures a first cycle required for the rotation axis to rotate by a predetermined angle at a first measurement point set on the rotation axis, and based on the first cycle, determines a first cycle. At a first measurement unit that calculates a first actual rotation speed at a measurement point, and at a second measurement point of a rotation axis separated from the first measurement point, a second cycle required for the rotation axis to rotate by a predetermined angle is measured. A second actual measuring unit that computes a second actual rotational speed at a second measuring point based on the second period. The first actual rotational speed computed by the first measuring unit as rotational component computing means; It is preferable to have a main arithmetic unit that calculates a true rotation speed and a torsional vibration component based on the second actual rotation speed calculated by the second measurement unit.

In this case, a first measurement point is set at, for example, one end of the rotation axis to be measured, and the first measurement point is set by the rotation speed measurement means.
Arrange the measuring unit. In addition, the second measurement point is located at a position separated from the first measurement point in the axial direction of the rotating shaft (for example, the other end of the rotating shaft).
A measuring point is set, and a second measuring unit of the rotation speed measuring means is arranged. The first measurement unit measures a first cycle required for the rotation axis to rotate by a predetermined angle at the first measurement point. At this time, if the rotation of the rotation axis at the first measurement point is converted into a pulse, the cycle T1 of the obtained pulse wave (first pulse wave) corresponds to the first cycle. The second measurement unit measures a second cycle required for the rotation axis to rotate by a predetermined angle at the second measurement point. At this time, if the rotation of the rotation axis at the second measurement point is converted into a pulse, the cycle T2 of the obtained pulse wave (second pulse wave) corresponds to the second cycle.

The first measuring section calculates the reciprocal (1 / T1) of the measured first cycle, and the second measuring section calculates the reciprocal (1 / T2) of the measured second cycle. Here, the first
The reciprocal of the cycle (1 / T1) is a value proportional to the first actual rotation speed at the first measurement point, and is the reciprocal of the second cycle (1 / T1).
2) is a value proportional to the second actual rotation speed at the second measurement point. Therefore, the reciprocal of the first cycle (1 / T1) and the reciprocal of the second cycle (1 / T2) themselves, or a value obtained by multiplying them by a constant as appropriate, are respectively used as the first actual rotation speed V1 (t).
And the second actual rotation speed V2 (t). In this specification, the term rotation speed (actual rotation speed, true rotation speed) is used as including a component proportional to the rotation speed such as an angular speed.

The first measuring section calculates the first actual rotation speed V1 (t)
The second measuring unit outputs a signal indicating the second actual rotation speed V2
The signal indicating (t) is given to the main operation unit of the rotation component operation means. The main computing unit performs a true rotation speed V (t) based on signals received from the first measurement unit and the second measurement unit.
And the torsional vibration component y (t) are calculated. By employing such a configuration, a rotation component measuring device that easily and accurately measures the true rotation speed and the torsional vibration component can be realized with a simple configuration.

Further, the apparatus further comprises a rotational phase difference measuring means for measuring a rotational phase difference between the first measuring point and the second measuring point of the rotating shaft, and the rotational phase difference measuring means measures the rotational phase difference. Torsion calculating a torsion angle of the rotating shaft based on the measured rotational phase difference and one of the first period measured by the first measuring unit and the second period measured by the second measuring unit. It is preferable to have an angle calculator.

In this case, the rotation phase difference measuring means calculates, for example, a time difference (timing shift) between the measurement timing of the first cycle by the first measurement unit and the measurement timing of the second cycle by the second measurement unit. It is measured as the rotational phase difference between the first measurement point and the second measurement point on the axis. That is, if the rotation of the rotation axis at the first measurement point and the rotation of the rotation axis at the second measurement point are respectively pulse-converted, the pulse wave (first pulse wave) obtained from the first measurement point and the second The phase difference ΔT from the pulse wave (second pulse wave) obtained from the measurement point corresponds to the rotation phase difference. The signal indicating the rotational phase difference (ΔT) obtained by the rotational phase difference measuring means is:
It is sent to the torsion angle calculator. In addition, the first measuring unit or the second measuring unit
Either one of the signal indicating the first cycle (T1) and the signal indicating the second cycle (T2) is sent from one of the measuring units to the torsion angle calculator.

The torsion angle calculator divides the rotational phase difference (ΔT) by the first period (T1) or the second period (T2) based on the received signal. That is, the torsion angle calculator calculates a value of ΔT / T1 or ΔT / T2.
Here, the value obtained by dividing the rotation phase difference by the first period or the second period is proportional to the torsion angle of the rotating shaft. This makes it possible to easily and accurately measure the torsion angle as the rotation component of the rotation shaft. In this specification, the term torsion angle is used as including a component proportional to the torsion angle.

According to a fourth aspect of the present invention, there is provided a method for measuring a rotational component of a rotating shaft, the method comprising: measuring various rotational components of a rotating shaft driven to rotate; A rotational speed measuring step of measuring an actual rotational speed, and a rotational component for calculating at least one of a true rotational speed and a torsional vibration component of the rotary shaft based on the actual rotational speeds at a plurality of locations measured in the rotational speed measuring step. And an operation step.

In the rotation speed measuring step, a first cycle required for the rotation axis to rotate by a predetermined angle is measured at a first measurement point set on the rotation axis, and a first cycle is measured based on the first cycle. While calculating the first actual rotation speed at the measurement point,
At a second measurement point of the rotation axis separated from the first measurement point, a second period required for the rotation axis to rotate by a predetermined angle is measured,
A second actual rotation speed at a second measurement point is calculated based on the second cycle, and in the rotation component calculation step, the true rotation speed and the torsional vibration component are calculated based on the first actual rotation speed and the second actual rotation speed. Is preferably calculated.

Further, the rotational phase difference of the rotating shaft between the first measurement point and the second measurement point is measured, and the difference between the rotational phase difference and one of the first cycle and the second cycle is measured. Preferably, the method further includes a torsion angle calculation step of calculating a torsion angle of the rotating shaft based on the torsion angle.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a rotation axis rotation component measuring apparatus and a rotation axis rotation component measurement method according to the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram of a rotation component measuring device (hereinafter, simply referred to as a “rotation component measuring device”) of a rotating shaft according to the present invention. Rotational component measuring device 1 shown in FIG.
Is, for example, a rotating shaft S included in various driving sources D such as an inverter motor and a diesel engine and rotationally driven.
Rotation component, that is, true rotation speed (true rotation speed) V
(T), torsional vibration component (modal response of torsional vibration)
y (t) and torsion angle θ. The rotation component measuring device 1 includes a rotation speed measurement block 2 (rotation speed measurement unit) that measures actual rotation speeds (actual rotation speeds at each position) at a plurality of positions (in this case, two positions) of the rotation axis S, A rotation component calculation block 20 (rotation component calculation means) for calculating various rotation components of the rotation axis S by performing arithmetic processing on a measurement value obtained by the rotation speed measurement block 2.
They are roughly divided into

The rotation speed measurement block 2 is disposed with respect to a first measurement point L1 set on the rotation axis S, and measures a first actual rotation speed V1 (t) of the rotation axis at the first measurement point L1. A first measuring unit 3 and a second measuring unit arranged for a second measuring point L2 set on the rotating axis S and measuring a second actual rotation speed V2 (t) of the rotating shaft at the second measuring point L2. 4 is included. Here, as shown in FIG. 1, the first measurement point L1 is set at one end of the rotation axis S, and the second measurement point L2 is
The torsional vibration mode is set at the other end of the rotating shaft S different from the first measurement point L1, being separated from the first measurement point by a predetermined distance. For example, in the case of a diesel engine, the first measurement point L1 and the second measurement point L2 can be set at both ends of a crankshaft serving as a rotation shaft S protruding from the engine casing.

As shown in FIG. 1, the first measuring section 3 has a first rotating body 5 fixed to a first measuring point L1 (one end) of the rotation axis S, and faces the first rotating body 5. 1st placed in
And a detector 7. The first rotating body 5 is a rotating gear formed of metal, and has a large number of external teeth formed at an outer periphery thereof at a predetermined pitch (for example, 6 °). On the other hand, the first detector 7 is composed of an electromagnetic pickup or the like, and utilizes the change of the magnetic field generated between the tooth tip and the valley of the first rotating body 5 rotating with the rotation axis S, and The pulse signal P1 is generated by detecting the passage of the external teeth. That is, the rotation of the rotation axis S at the first measurement point L1 is pulse-converted by the first rotating body 5 and the first detector 7 (first detecting unit).

Similarly, the second measuring section 4 also performs the second measurement of the rotation axis S.
It includes a second rotating body 6 fixed to the measurement point (the other end), and a second detector 8 arranged to face the second rotating body 6. The second rotating body 6 is also a rotating gear formed of metal, and has a large number of external teeth formed at a predetermined pitch on the outer periphery thereof. The second detector 8 also includes an electromagnetic pickup or the like, and similarly to the first detector 7, detects a change in a magnetic field generated between the tooth tip and the valley of the second rotating body 6 that rotates together with the rotation axis S. Using this, the external teeth of the second rotating body 6 are detected to generate a pulse signal P2. That is, the rotation of the rotation axis S at the second measurement point L2 is also determined by the second rotating body 6 and the second detector 8.
(Second detection unit) to perform pulse conversion.

The number of teeth n2 of the second rotating body 6 is
It is not necessary to match the number of teeth n1 with the number of teeth n2.
Although it may be set to an integral multiple of 1 or the like, in this rotation component measuring device 1, the number of teeth n1 of the first rotating body 5 and the number of teeth n2 of the second rotating body 6 Are set to the same number. When the rotational component measuring device 1 is applied to a diesel engine, a flywheel provided on a crankshaft of the diesel engine may also be used as the first rotating body 5 or the second rotating body 6. . Further, an optical detector such as a rotary encoder may be used instead of the rotating bodies 5 and 6 and the detectors 7 and 8.

The first measuring section 3 includes a first waveform shaper 9 connected to the first detector 7 and the first waveform shaper 9.
And the first counter 11 connected to the first counter 11. That is, the pulse signal P1 generated by the first detector 7
Is shaped into a rectangular wave by the first waveform shaper 9 (see FIG. 5), and then sent to the first counter 11. Similarly,
The second measuring section 4 includes a second waveform shaper 10 connected to the second detector 8 and a second counter 12 connected to the second waveform shaper 10. The pulse signal P2 generated by the second detector 8 is also sent to the second counter 12 after being shaped into a rectangular wave by the second waveform shaper 10 (see FIG. 5).

As shown in FIG. 1, the first counter 11 is connected to a high-frequency reference signal generator 14 for generating a high-frequency pulse signal of, for example, 1 MHz. The first counter 11 operates using the pulse signal P1 received from the first detector 7 via the first waveform shaper 9 as a gate signal, and once receives the pulse signal P1, returns to the next pulse signal P1.
Until the high-frequency pulse signal received from the high-frequency reference signal generator 14 is received. Similarly, a high-frequency reference signal generator 14 is also connected to the second counter 12, and the second counter 12 gates a pulse signal P2 received from the second detector 8 via the second waveform shaper 10. And counts the high-frequency pulse signals received from the high-frequency reference signal generator 14 from the time when the pulse signal P2 is once received until the time when the next pulse signal P2 is received.

Further, the first measuring unit 3 includes a first computing unit 15
And the second measuring unit 4 includes a first computing unit 16. That is, the first arithmetic unit 15 is connected to the first counter 11, and the first counter 11 supplies a signal indicating the count number to the first arithmetic unit 15. When receiving the signal from the first counter 11, the first computing unit 15 calculates the reciprocal of the count number counted by the first counter 11. Similarly, a second computing unit 16 is connected to the first counter 12, and the second counter 12 supplies a signal indicating the count number to the second computing unit 16. The second computing unit 16
When a signal is received from the second counter 12, the reciprocal of the count number counted by the second counter 12 is calculated.

The first computing unit 15 of the first measuring unit 3 and the second computing unit 16 of the second measuring unit 4 are connected to the main computing unit 21 included in the rotation component computing block 20, respectively. The first computing unit 15 outputs a signal indicating the reciprocal of the count number counted by the first counter 11, and the second computing unit 16
A signal indicating the reciprocal of the count number counted by the counter 12 is sent to the main operation unit 21 of the rotation component operation block 20.
Give to. The main computing unit 21 performs a predetermined computation based on the signals received from the first computing unit 15 and the second computing unit 16 to calculate a true rotation speed V (t) and a torsional vibration component y (t). I do.

The rotation component measurement device 1 (rotation speed measurement block 2) includes a third counter 13. The third counter 13 is connected to the first waveform shaper 9, the second waveform shaper 10, and the high-frequency reference signal generator 14. The third counter 13 operates the pulse signals P1 and P2 received from the first detector 7 and the second detector 8 via the first waveform shaper 9 and the second waveform shaper 10 as gate signals, and operates as a pulse signal. During the period from when the signal P1 is received to when the pulse signal P2 is received, the high-frequency pulse signals received from the high-frequency reference signal generator 14 are counted.

The third counter 13 is connected to a torsion angle calculator 22 included in the rotation component calculation block 20. Then, the third counter 13 gives a signal indicating the count number to the torsion angle calculator 22. The torsion angle calculator 22 is connected to the second counter 12 of the second measuring unit 4, and the second counter 12 supplies a signal indicating the number of counts to the torsion angle calculator 22. Torsion angle calculator 2
2 is the output signal of the second counter 12 and the third counter 1
3 is calculated based on the output signal of the rotation axis 3 and the rotation axis S
Is calculated. Note that instead of connecting the torsion angle calculator 22 and the second counter 12 of the second measuring unit 4, the torsion angle calculator 22 and the first counter 11 of the first measuring unit 3 may be connected.

The rotation component measuring device 1 employing such a configuration realizes easy and accurate measurement of the true rotation speed, the torsional vibration component, and the torsion angle with a simple configuration. .

Next, the calculation procedure (rotational component measuring method) of various rotational components by the above-described rotational component measuring device 1 will be described.

When the rotational component measuring device 1 is used, a rotational speed measuring block 2 is arranged with respect to a rotational axis S of a drive source D to be measured. That is, the first rotating body 5 included in the first measuring unit 3 is fixed to the first measurement point L1 of the rotation axis S, and the second measurement point L2 of the rotation axis S separated from the first measurement point L1 is fixed to the first measurement point L1. Then, the second rotating body 6 included in the second measuring unit 4 is fixed. At this time, the extending direction (depth direction) of any one of the external teeth of the second rotating body 6 is the extending direction (depth direction) of any one of the external teeth included in the first rotating body 5. Is fixed to the rotation axis S in a state that coincides with. Further, the first detector 7 is arranged so as to face the first rotating body 5, and the second detector 8 is arranged so as to face the second rotating body 6. Then, from this state, the drive source D is operated to rotate the rotation shaft S.

Here, even if the rotation axis S rotates, the rotation axis S
If the torsional vibration does not occur, the first actual rotation speed V1 (t) at the first measurement point of the rotation axis S and the second actual rotation speed V2 (t) at the second measurement point are both shown in FIG. As shown in the figure, the two should be consistent. In this case, the first detector 7 and the second detector 8 emit the pulse signals P1 and P2 at the same interval (the same cycle).

However, actually, a torsional vibration as shown in FIG. 3 is generated at an arbitrary position on the rotation axis S, and the first actual rotation speed V1 (t) directly measured from the rotation axis S is expressed by:
As shown in FIG. 4, the second actual rotation speed V2 (t)
The true rotational speed V (t), which is a net rotational speed excluding the effect of torsion, and a torsional vibration component y (t) are included. For this reason, a so-called rotation speed unevenness appears on the surface of the rotation axis S, so that the pulse signal P1 emitted from the first detector 7 of the first measurement unit 3 and the second detector of the second measurement unit 4 When the pulse signal P2 generated from the second measurement point L2 is formed into a waveform, as shown in FIG. 5, the period T1 of the first pulse wave W1 corresponding to the first measurement point L1 and the second pulse wave corresponding to the second measurement point L2 The value is different from the cycle T2 of W2.

Here, since the period of the high-frequency pulse signal generated by the high-frequency reference signal generator 14 is constant, the count number of the first counter 11 can be substantially obtained by waveform-forming the pulse signal P1. This corresponds to the period T1 of one pulse wave W1, and the count number of the second counter 12 substantially corresponds to the period T2 of the second pulse wave W2 obtained by forming the pulse signal P2 into a waveform. As a result, in the first counter 11 of the first measuring section 3, the period T1 of the first pulse wave W1, that is, the time required for the rotation axis S to rotate by 2π / n1 (rad) at the first measurement point (the second time). 1 cycle) is measured, and the second
In the second counter 12 of the measuring unit 4, the rotation axis S is 2 at the period T2 of the second pulse wave W2, that is, at the second measurement point.
The time required to rotate by π / n2 (rad) (second
Cycle) is being measured.

The value calculated by the first computing unit 15 is the reciprocal of the count number counted by the first counter 11,
This value is the reciprocal of the period T1 of the first pulse wave W1, that is, the first actual rotation speed V1 at the first measurement point L1.
It is proportional to (t). Further, the value calculated by the second calculator 16 is the reciprocal of the count number counted by the second counter 12, and the value is the reciprocal of the cycle T2 of the second pulse wave W2, that is, the second measurement point L2 Is proportional to the second actual rotation speed V2 (t). Therefore, the calculation result of the first calculator 15 of the first measuring unit 3 and the calculation result of the second calculator 16 of the second measuring unit 4 (or a value obtained by multiplying them by a constant) are converted to the first measurement point L1. And the second actual rotation speed V2 (t) of the rotation axis S at the first measurement point L1. In such a procedure, the rotation speed measurement block 2 performs a plurality of steps (the first measurement point L1 and the second measurement point L
The actual rotation speeds V1 (t) and V2 (t) in 2) are calculated.

When the actual rotation speeds V1 (t) and V2 (t) at a plurality of positions on the rotation axis S are obtained in this manner, the true rotation speed V (t) and the torsional vibration component y (t) are calculated. Simultaneous equations consisting of the above equations (1) and (2) can be established as unknowns. Then, the true rotational speed V, which is the solution of the simultaneous equations consisting of the above equations (1) and (2),
(T) and the torsional vibration component y (t) are as follows: V (t) = K1 · V1 (t) −K2 · V2 (t) (3) y (t) = ｛V1 (t) −V2 ( t)｝ / {φ1−φ2} (4) K1 and K2 are constants represented by torsional vibration modes φ1 and φ2, and K1 = 1 / {1−φ1 / φ2} (5) K2 = {φ1 / φ2} / {1−φ1 / φ2｝ (6) Rotation component calculation block 20
The main arithmetic unit 21 has a first actual rotation speed V1 (t) and a second actual rotation speed V1 (t) indicated by signals received from the first arithmetic unit 15 of the first measurement unit 3 and the second arithmetic unit 16 of the second measurement unit 4. Substituting the rotation speed V2 (t) into the above equations (3) and (4),
The true rotation speed V (t) and the torsional vibration component y (t) are calculated.

As described above, according to the rotation component measuring device 1, the true rotation speed V of the various rotation components of the rotation axis S is obtained.
At least one of (t) and the torsional vibration component y (t) can be easily and accurately obtained.

On the other hand, when torsional vibration occurs on the rotation axis S, a rotation phase difference occurs between the first measurement point L1 and the second measurement point L2 of the rotation axis. Due to this,
When the pulse signal P1 and the pulse signal P2 are formed into a waveform, a phase difference ΔT is generated between the first pulse wave W1 and the second pulse wave W2 as shown in FIG. This phase difference ΔT is
The time difference between the input timing of the pulse signal P1 to the first counter 11 and the input timing of the pulse signal P2 to the second counter 12, that is, the measurement timing of the first cycle (T1) by the first measurement unit 3, and the second measurement Part 4
Is measured by the third counter 13 as a shift of the measurement timing of the second cycle (T2) due to the above. As described above, the third counter 13 determines the first measurement point L1 of the rotation axis S.
It functions as a rotation phase difference measuring means for measuring the rotation phase difference (ΔT) between the second measurement point L2 and the second measurement point L2.

Therefore, a signal provided from the third counter 13 to the torsion angle calculator 22 of the rotation component calculation block 20 includes a rotation phase difference (R) between the first measurement point L1 and the second measurement point L2 of the rotation axis. ΔT) is shown. In addition, the signal provided from the second counter 12 of the second measuring unit 4 to the torsion angle calculator 22 includes the period T2 of the second pulse wave W2, that is, the rotation axis S at the second measurement point is 2π / n2 (ra).
The time (second cycle) required to rotate by d) is shown. The torsion angle calculator 22 divides the rotational phase difference by a second cycle based on the signals received from the second counter 12 and the third counter 13. That is, the torsion angle calculator 22 calculates a value of ΔT / T2. Here, the value obtained by dividing the rotation phase difference (ΔT) by the second period (T2) is proportional to the torsion angle θ of the rotating shaft. As a result, the torsion angle θ as a rotation component of the rotation axis S
Can be easily and accurately calculated.

As described above, the rotation component measuring device 1
The rotation components such as the true rotation speed V (t), the torsional vibration component y (t), and the torsion angle θ of the rotating shaft S that is rotationally driven are calculated. It can be used as follows. First, using the torsional vibration component y (t), it becomes possible to monitor the fatigue state of the rotating shaft S provided in the various driving sources D. That is, if the torsional vibration component y (t) is obtained, the torsional stress generated on the rotation axis S can be obtained, and the rotation axis S using a well-known method such as a peak counting method, a range method, and a Rembebeer method. , The fatigue life can be easily estimated. This makes it possible to prevent damage caused by cracks, damage, and the like occurring on the rotation shaft S beforehand.

Further, it is possible to appropriately control the driving of the rotating shaft S using the true rotation speed V (t) and the torsional vibration component y (t). Generally, in diesel engines, etc.,
The actual rotation speed is measured from one point such as a crankshaft as a rotation shaft, and based on the measured actual rotation speed, the fuel injection amount,
In general, the injection timing and the like are controlled. On the other hand, if the rotation component measuring device 1 is incorporated in a control unit such as a diesel engine, the true rotation speed V (t) of the crankshaft is obtained.
, It is possible to control the fuel injection amount, injection timing, and the like. Further, if the rotation component measuring device 1 is incorporated in the control unit of the inverter motor, the influence of the torsional vibration component superimposed on the torque feedback control signal can be eliminated, or the true rotation speed V can be used as the speed feedback control signal.
For example, a signal indicating (t) can be used. Thus, the efficiency of the various driving sources D can be improved and improved.

Further, the torsion angle θ is a parameter proportional to the output (torque) of each drive source D. Therefore, it is possible to obtain the outputs actually generated by the various drive sources D from the torsion angle θ obtained by the rotation component measuring device 1 and control the drive sources D so as to match the preset load. Become. Further, if the torque is obtained from the torsion angle θ obtained by the rotation component measuring device 1, it is possible to monitor the torque fluctuation of the driving source D. Also in this case, it is possible to improve and improve the efficiency of the various driving sources D.

As described above, the rotation component measuring device 1 has an extremely wide range of application. In the present embodiment, the actual rotation speed V1 at two positions of the rotation axis S
Although (t) and V2 (t) are measured, the present invention is not limited to this, and the actual rotation speed may be measured at three or more locations (three locations having different torsional vibration modes) of the rotation axis S. . Thereby, the accuracy of the calculated rotation component can be improved.

[0050]

As described above, according to the present invention,
The following effects can be obtained. That is, the actual rotation speed at a plurality of locations on the rotation shaft is measured by the rotation speed measurement unit, and the true rotation speed and the torsional vibration of the rotation shaft are calculated from the actual rotation speed measured by the rotation speed measurement unit using the rotation component calculation unit. By calculating at least one of the components, it is possible to monitor the fatigue state of the rotating shaft provided in various driving sources and the like, and to drive the rotating shaft using the obtained true rotational speed and the torsional vibration component. It becomes possible to control appropriately. Therefore, it is possible to extremely easily achieve a longer life and an improved efficiency of various driving sources.

[Brief description of the drawings]

FIG. 1 is a block diagram of a rotation component measurement device of a rotation shaft according to the present invention.

FIG. 2 is a chart for explaining an actual rotation speed when it is assumed that torsional vibration does not occur on a rotating shaft.

FIG. 3 is a table for explaining torsional vibration generated on a rotating shaft.

FIG. 4 is a table for explaining an actual rotation speed of a rotating shaft.

FIG. 5 is a time chart of a pulse signal obtained by pulse-changing the rotation of the rotating shaft.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotation component measuring device, 2 ... Rotation speed measurement block (rotation speed measurement means), 3 ... First measurement part, 4 ... Second measurement part,
5 first rotator, 6 second rotator, 7 first detector, 8
... second detector, 11 ... first counter, 12 ... second counter, 13 ... third counter, 14 ... high frequency reference signal generator, 15 ... first calculator, 16 ... second calculator, 20 ... rotational component Operation block (rotational component operation means), 21: main operation unit, 22: torsion angle operation unit, D: drive source, L1: first measurement point, L2: second measurement point, P1, P2: pulse signal, S
... Rotary axis, T1 ... Period of first pulse wave (first period), T
2: cycle of second pulse wave (second cycle), V (t): true rotation speed, V1 (t) ... first actual rotation speed, V2 ... second actual rotation speed, y (t) ... torsional vibration component , Θ ... torsion angle, △
T: phase difference (rotation phase difference).

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G01D 5/245 G01D 5/245 B G01H 1/10 G01H 1/10 F term (Reference) 2F069 AA88 AA99 CC04 CC10 DD06 GG04 GG06 GG07 GG41 GG63 HH13 HH15 JJ17 MM04 MM11 NN08 2F077 AA49 NN22 PP05 TT21 TT32 TT35 TT75 TT78 2G024 AA06 BA12 CA03 CA09 CA14 DA09 EA00 2G064 AA17 AB10 CC29 3G08A FA04

Claims (6)

[Claims] An apparatus for measuring a rotational component of a rotating shaft that measures various rotational components of a rotating shaft that is driven to rotate, a rotating speed measuring unit that measures actual rotational speeds at a plurality of positions on the rotating shaft, A rotation component calculating unit that calculates at least one of a true rotation speed of the rotation shaft and a torsional vibration component based on the actual rotation speeds at the plurality of locations measured by the speed measurement unit. A rotation component measuring device for the rotating shaft. 2. The rotation speed measuring means measures a first cycle required for the rotation axis to rotate by a predetermined angle at a first measurement point set on the rotation axis, based on the first cycle. A first measuring unit that calculates a first actual rotation speed at the first measurement point; and a second measurement point of the rotation axis that is separated from the first measurement point. Cost second
A second measuring unit that measures a cycle and calculates a second actual rotation speed at the second measuring point based on the second cycle, wherein the rotation component calculating unit calculates the rotation component by the first measuring unit. A main arithmetic unit that calculates the true rotation speed and the torsional vibration component based on the first actual rotation speed and the second actual rotation speed calculated by the second measurement unit. The rotation component measurement device for a rotation shaft according to claim 1. 3. The method according to claim 2, wherein the first measurement point of the rotation axis is connected to the second measurement point.
A rotation phase difference measurement unit that measures a rotation phase difference between the measurement point and the rotation point difference measured by the rotation phase difference measurement unit; and the first measurement unit. A torsion angle calculator for calculating a torsion angle of the rotating shaft based on one of the first period measured by the first measuring unit and the second period measured by the second measuring unit. The rotation component measuring device for a rotating shaft according to claim 2, wherein 4. A method for measuring a rotational component of a rotating shaft for measuring various rotational components of a rotating shaft that is rotationally driven, wherein: a rotating speed measuring step of measuring actual rotational speeds at a plurality of locations on the rotating shaft; A rotation component calculation step of calculating at least one of a true rotation speed of the rotation shaft and a torsional vibration component based on the actual rotation speeds of the plurality of locations measured in the speed measurement step. Method. 5. In the rotation speed measuring step, a first cycle required for the rotation axis to rotate by a predetermined angle is measured at a first measurement point set on the rotation axis, and based on the first cycle, Calculating a first actual rotation speed at the first measurement point, and a second cycle required for the rotation axis to rotate by a predetermined angle at a second measurement point of the rotation axis separated from the first measurement point. Is calculated, and a second actual rotation speed at the second measurement point is calculated based on the second cycle. In the rotation component calculation step, the second actual rotation speed is calculated based on the first actual rotation speed and the second actual rotation speed. The method according to claim 4, wherein the true rotation speed and the torsional vibration component are calculated. 6. The first measurement point of the rotation axis and the second measurement point.
A torsion angle for measuring a rotation phase difference between the measurement point and a torsion angle of the rotation shaft based on the rotation phase difference and one of the first cycle and the second cycle. The method according to claim 5, further comprising an operation step.