WO1998030869A1

WO1998030869A1 - Method of measuring information on rotation of rotary body, and instrument for measuring information on rotation

Info

Publication number: WO1998030869A1
Application number: PCT/JP1998/000032
Authority: WO
Inventors: Kazuo Suzuki; Takanori Nanya; Takayasu Machida; Shigeyuki Takahashi; Takeaki Shimanouchi; Hideki Shimizu
Original assignee: Citizen Watch Co., Ltd.
Priority date: 1997-01-08
Filing date: 1998-01-08
Publication date: 1998-07-16
Also published as: JP2002122493A

Abstract

A reflective surface (1b) which is inclined with respect to the rotation axis (1c) of the rotary shaft (1a) of a rotary body (1) which is an object to be measured is formed on the tip of the rotary shaft (1a). A light beam is applied to the reflective surface (1b) by a light beam emitting unit (2) in a direction along the rotation axis (1c). After the rotation of the rotary unit (1) is started, light reflected by the reflective surface (1b) is detected by a plurality of photodetectors of reflected light detectors (3) which are installed on the same circle whose center is the rotation axis (1c). The time from a reference time till the time when reflected light is detected by each photodetector is measured by a rotation angle time information measuring unit (4) as time information on the rotation angle of the rotary unit (1). By calculating the rotation angle time information with an arithmetic unit (6), accurate information such as the angular velocity, angular acceleration, torque and energy can be obtained over the rotation angle of the rotary unit (1).

Description

Description Rotational body rotation information measurement method and rotation information measurement device

The present invention relates to a rotation information measuring method and a rotation information measuring device for non-contact and accurate measurement of rotation angle time information, angular velocity, angular acceleration, torque, and energy as rotation information when a small rotating body rotates. About. Background technology

For example, in order to grasp the rotation status of a small rotating body such as a step motor or a micro motor rotor used as an actuator for driving the hands of a watch, a small torque or small energy during rotation can be used as the rotation information. Need to be measured. Conventionally, such a method of measuring a small torque of a rotating body includes a method of estimating a generated torque of the rotating body by bringing a reference load torque generator into contact with the rotating body of the object to be measured, and a method of measuring a small torque of the rotating body. A method has been adopted in which a torque measuring instrument using a strain gauge or the like is connected to measure the torque generated by the rotating body.

Therefore, when the generated torque of the rotating body was sufficiently large with respect to the reference load, the generated torque could be estimated almost accurately. However, when the generated torque of the rotating body is smaller than the reference load, the behavior of the rotating body changes depending on the presence or absence of the reference load and the presence of the torque measuring instrument inertia. Finally, it was difficult to measure the torque during rotation because the rotating body could not rotate.

For this reason, there are many needs to evaluate the performance of micromotors and the like, but with the conventional method, it was not possible to accurately measure minute torque when a small rotating body was rotating. Similarly, it was difficult to accurately measure the minute energy during the rotation. The present invention has been made in order to solve such a problem, and the rotation information at the time of rotation of the small rotating body as described above, that is, the time information of the rotation angle, the angular velocity, the angular acceleration, the torque, and the energy are obtained. It is an object of the present invention to provide a rotation information measurement method that enables accurate measurement without contact, and a rotation information measurement device for implementing the measurement method. Disclosure of the invention

In order to achieve the above object, in the method for measuring rotation information of a rotating body according to the present invention, a reflection surface inclined with respect to the rotation axis is formed at the tip of the rotating shaft of the rotating body to be measured. .

Then, during the rotation of the rotating body, the reflecting surface is irradiated with a light beam from a direction along the rotation axis. After the rotation of the rotating body starts, the light reflected by the reflecting surface is centered on the rotating axis. By detecting with a plurality of photodetectors arranged at a predetermined angular interval on the same circumference, the elapsed time from the reference time to the detection of the reflected light by each of the plurality of photodetectors can be calculated. It is measured as time information of the rotation angle of the rotating body.

By differentiating the time information of the rotation angle with respect to time, the angular velocity of the rotating body can be measured.

By further differentiating the angular velocity with time, the angular acceleration of the rotating body can be measured.

Further, by multiplying the angular acceleration by the moment of inertia (also referred to as inertia) of the rotating body, the torque acting on the rotating body can be measured.

Then, by integrating the torque in the rotation angle range where the torque is measured after the rotation of the rotation body is started, the energy of rotation of the rotation body at the end of the rotation angle range can be measured. it can. Alternatively, assuming that the angular velocity measured at a certain time is ω and the inertia moment of the rotating body is I, the rotational energy 回転 of the rotating body at the time is

Ε = (ΐ / 2) · Ι · It can also be obtained and calculated by calculating ω ² .

In addition, in order to perform the above-described measurement method, the rotation information measuring device for a rotating body according to the present invention measures a rotating body having a reflecting surface inclined at an end of a rotating shaft with respect to the rotating axis as a measurement object, An apparatus for measuring rotation information of the rotating body, comprising at least the following means.

The respective means are a light beam irradiating means for irradiating the reflecting surface with a light beam during rotation of the rotating body from a direction along the rotation axis, and a light beam irradiating means on the same circumference around the rotation axis. Reflected light detecting means comprising a plurality of light detecting elements arranged so as to detect reflected light from the reflecting surface at an angular interval, and after the rotation of the rotator starts rotating, the reflected light from the reflecting surface is detected by the plurality of light detecting elements. Means for measuring the elapsed time from the reference time to the detection of the reflected light by each of the plurality of light detection elements as time information of the rotation angle of the rotating body. is there.

Further, if an angular velocity calculating means for calculating an angular velocity by differentiating the measured time information of the rotation angle with respect to time is provided, the angular velocity of the rotating body can be measured.

Furthermore, if an angular acceleration calculating means for calculating the angular acceleration by differentiating the measured angular velocity with respect to time is provided, the angular acceleration of the rotating body can be measured.

Then, by multiplying the measured angular acceleration by the moment of inertia of the rotating body to provide a torque calculating means for calculating a torque acting on the rotating body, the torque of the rotating body can be measured.

Furthermore, if energy calculating means for integrating the measured torque within the rotation angle range where the torque is measured after the rotation of the rotating body is provided, the end of the rotation angle range is provided. The rotation energy of the rotating body can be measured.

Alternatively, from the angular velocity ω measured at a certain time and the inertia moment I of the rotating body, the rotational energy エネルギー of the rotating body at the time is

Ε = (1/2) · it · ω may be provided with energy calculation means for calculating the ^second computing.

If the driving means for driving the rotating body is provided, the rotation information of the rotating body having no rotating driving means can be measured.

In each of the rotation information measuring devices described above, if display means for displaying rotation information such as torque energy calculated by each calculation means is provided, the measurement can be performed while visually confirming the measurement result. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a block diagram showing an embodiment of a rotation information measuring device for a rotating body according to the present invention.

FIG. 2 is a sectional view of a two-pole step motor having a rotor which is a rotating body to be measured according to the first embodiment of the present invention.

FIG. 3 is a side view showing the arrangement of the light beam irradiation means and the reflected light detection means of the rotation information measuring device of the first embodiment with respect to the reflecting surface of the rotating shaft of the rotating body.

FIG. 4 is a plan view showing the arrangement of each photodetector of the reflected light detecting means. FIG. 5 is a diagram showing a display example of rotation angle time information, angular velocity, and angular acceleration as the measurement result.

FIG. 6 is a diagram showing a display example of the torque and the energy.

FIG. 7 is a perspective view of a photodiode array used for reflected light detecting means in a second specific embodiment of the present invention.

FIG. 8 shows a rotation information measuring device according to a third embodiment of the present invention together with a rotating body. FIG.

FIG. 9 is a plan view of the annular photodiode array 38 in FIG. FIG. 10 is a block circuit diagram showing a specific example of the rotation angle time information measuring means and storage means in the third embodiment.

FIG. 11 is a timing chart showing the relationship between the parallel pulse signal and the serial pulse signal in FIG. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a rotation information measuring apparatus for a rotating body according to the present invention.

This rotation information measuring device is a rotating object 1 having a reflecting surface 1b formed at a tip of a rotating shaft 1a and inclined with respect to a plane perpendicular to the rotating axis 1c. It is a device that measures information.

And a light beam irradiating means 2 for irradiating the reflecting surface 1b with a light beam from the direction along the rotation axis 1c while the rotating body 1 is rotating, and a predetermined light beam on the same circumference around the rotation axis 1c. Reflected light detecting means 3 composed of a plurality of light detecting elements arranged to detect the reflected light from the reflecting surface 1b at an angular interval, and the reflecting surface 1b after the rotation of the rotating body 1 starts By detecting the reflected light with the plurality of light detection elements of the reflected light detection means 3, the elapsed time from the reference time to the detection of the reflected light by each of the plurality of light detection elements is determined by the rotation of the rotating body 1. The rotation angle time information measuring means 4 for measuring the angle time information has a minimum required configuration.

This example further includes a storage unit 5, a calculation unit 6, and a display unit 7, a drive unit 8 for driving the rotating body 1 to rotate, and a drive waveform generation unit 9 for generating an arbitrary drive waveform thereof. . When the driving means is provided on the rotating body 1, this measurement It is not necessary to provide the driving means 8 and the driving waveform generating means 9 on the fixed device side.

By using this measuring device, the method for measuring rotation information of a rotating body according to the present invention can be implemented.

That is, during the rotation of the rotating body 1, the light beam irradiating means 2 emits light from the direction along the rotating axis 1 c of the rotating body 1 to the reflecting surface 1 b formed at the tip of the rotating shaft 1 a while being inclined. After the rotation of the rotating body 1 is started, the reflected light from the reflecting surface 1b is separated by a predetermined angle on the same circumference around the rotation axis 1c constituting the reflected light detecting means 3. The rotation angle time information measuring means measures the elapsed time from the reference time to when the reflected light is detected by each of the plurality of light detection elements. It is measured as time information of the rotation angle of the rotating body 1. Then, after temporarily storing the rotation time information for each predetermined rotation angle in the storage means 5, the necessary rotation information is calculated by the calculation means 6 and displayed on the display means 7. The calculating means 6 includes: an angular velocity calculating means for calculating angular velocity by differentiating the time information of the rotation angle with time; an angular acceleration calculating means for calculating angular acceleration by differentiating the angular velocity with time; It has the function of torque calculation means for calculating the torque acting on the rotating body 1 by multiplying the angular acceleration by the moment of inertia (also referred to as inertia) of the rotating body 1.

Further, the calculation means 6 integrates the torque in the rotation angle range where the torque is measured after the rotation of the rotating body 1 is started, thereby calculating the rotation energy of the rotating body at the end of the rotation angle range. From the energy calculation means or the angular velocity ω measured at a certain point in time and the moment of inertia I of the rotating body 1, the rotational energy 持つ of the rotating body 1 at the time is given by Ε = (ΐΐ 2) function of the energy calculating means for calculating the operation iota · omega ² can also be given.

Then, the calculation results can be displayed on display means 7 such as a CTR display or a liquid crystal display. Next, as a specific first embodiment of the present invention, a two-pole step in which a rotating body 1 to be measured by the rotation information measuring device is used as an actuator for rotating a clock hand An example in the case of a rotor of a motor will be described with reference to FIGS. 2A to 6.

2A and 2B are a cross-sectional view of a two-pole step motor having a rotor as the rotating body 1 and a perspective view of the rotor 1, and FIG. 3 is a reflection surface of the rotating shaft 1a of the rotating body 1. FIG. 4 is a side view showing the arrangement of the light beam irradiating means 2 and the reflected light detecting means 3 of the rotation information measuring device with respect to 1b, and FIG. 4 is also a plan view showing the arrangement of each photodetector of the reflected light detecting means 3. is there.

The two-pole step motor 10 shown in FIG. 2A has a rotor 1 (hereinafter referred to as “rotor 1”) provided in a stator 12, and the stator 12 has a coil 1. The coil 3 is wound, and is excited by applying a drive pulse to the coil 13 to rotate the rotor 1 stepwise.

As shown in Fig. 2B, the rotor 1 has a rotating shaft 1a penetrating the center of the rotor 1 and is provided on the body. A small gear (kana) 14 is fitted and fixed to the rotating shaft la. ing. The rotating shaft 1 a is rotatably supported by bearings of the train wheel receiver 15 and the base plate 16.

Further, the end surface of the rotating shaft 1a protruding from the train wheel receiver 15 is obliquely mirror-polished to form a reflecting surface 1b inclined at an angle 0 with respect to the rotating axis 1c. In this example, the tilt angle 0 is about 45 degrees.

The reflecting surface lb is a light reflecting portion having a reflecting surface 1 b inclined with respect to the rotation axis 1 c on the tip surface of the rotating shaft 1 a instead of directly mirror-finishing the tip of the rotating shaft 1 a. It may be formed by sticking a material. However, in that case, it is desirable that the mass of the rotating body 1 be as small as possible so as not to affect the behavior of the rotating body 1. Considering that the installation position of the light reflecting member is on the rotation axis, in reality, the mass of the light reflecting member is If it is less than 1% of the mass of the rotor 1, there is almost no effect.

As shown in FIG. 3, the light beam irradiating means 2 has a holder 21 fixed to the upper part of a column 18 standing on a base plate 17 with mounting screws 22, and the holder 2 1 A semiconductor laser 23 as a light source is mounted on the upper support piece 21a extending horizontally, and a condenser lens 24 is mounted on the lower support piece 21b so that the optical axis coincides with the rotation axis 1c of the rotation axis 1a. I have.

The semiconductor laser 23 emits laser light having a peak at a wavelength near 900 nm in the near infrared region. The laser light is condensed by a condensing lens 24 to form a thin laser beam LB, and is rotated from the through hole 21 c of the lower support piece 21 b along the rotation axis 1 c (vertically in the example shown). Irradiate the central part of the reflective surface 1b of the axis 1a.

At this time, since the incident angle of the laser beam LB with respect to the reflecting surface 1b is 45 degrees, the reflection angle is also 45 degrees, and the reflected light LR is directed in a direction orthogonal to the rotation axis 1c (in the illustrated example, the horizontal direction). ) Is reflected in the plane of. If the angle of inclination of the reflecting surface 1b with respect to the rotation axis 1c is not 45 degrees, the light is reflected within the conical surface. These planes or conical surfaces are called the sweep surfaces formed by the reflected light.

As shown in FIGS. 3 and 4, the reflected light detecting means 3 includes a photodetector 32 provided with a photodetecting element 31 such as a photo diode or a phototransistor, and a rotating axis 1 c of the rotating body 1. On the same circumference (indicated by dashed-dotted line 33 in FIG. 4) on the above-mentioned sweeping surface as the center, a large number are arranged at predetermined angular intervals toward the center of the reflecting surface 1b. In the example shown in FIG. 4, the point at which the reflected light arrives when the rotor 1 is stationary is the base point P. As a result, a total of 38 photodetectors 32 (channels CH1 to CH38) were arranged at 6-degree intervals.

Since the rotation angle of the rotor 1 by one-step driving by the two-pole step motor for a watch is 180 degrees, the angle α of the overshoot is 42 degrees, and the angle α is 42 degrees. This is for measuring rotation information. As shown in FIG. 3, each photodetector 32 is non-rotatably supported by a column 34 standing on a base plate 17 and a feed screw 35 parallel thereto. By rotating 5, the height position can be adjusted according to the incident position of the reflected light LR. Reference numeral 36 denotes a coil spring for removing backlash between the feed screw 35 and the photodetector 32.

As a photodetector 31 of each photodetector 32, a photodiode (PH-302, manufactured by NEC) is used, so that the wavelength of the laser light emitted from the semiconductor laser 23 can be adjusted. We succeeded in achieving high-speed response by tuning. However, the light detection element only needs to be able to detect the reflected light L R, and therefore, other than the photo diode may be used depending on the compatibility with the light source of the light beam irradiation means 2.

According to this rotation information measuring device, since the angular position of each light detecting element 31 of the reflected light detecting means 3 from the base point P o is known, the rotor 1 is stepped by the step driving of the two-pole step motor 10. When it is rotated, it is the starting point of its drive or the base point P of the photodetector 32. When the photodetector 31 at the point where the reflected light L R is no longer detected (these

From the “reference time”, the elapsed time (corresponding to the rotation time) until the photodetector 31 of each photodetector 32 detects the reflected light LR is measured sequentially by sweeping the reflected light LR. As a result, time information of the rotation angle of the rotor 1 that has started rotating can be obtained with high accuracy. By using a microcomputer as the time information measuring means 4 of the rotation angle shown in FIG. 1 and performing time management of the entire device, it is relatively easy to obtain time information for the rotor rotation angle having an accuracy of about 1 s. can get.

The obtained time information on the rotation angle is temporarily stored in the storage means 5, and then converted by the calculation means 6 into the above-mentioned physical quantity of the angular velocity, angular acceleration, torque, or energy, which is known. Will be displayed.

FIGS. 5 and 6 show display examples of the measurement results, that is, various kinds of rotation information when the rotor of the two-pole step motor is the measurement target. Curve 71 shown in (a) of FIG. 5 is time information with respect to the rotation angle measured by the rotation angle time information measuring means 4, the rotation time being represented by the rotation time on the horizontal axis and the rotation angle on the vertical axis. It is a curve which shows the time characteristic of an angle (rad).

A curve 72 shown in (b) of the figure is a curve showing a time characteristic of an angular velocity (rad / sec) obtained by differentiating the time characteristic of the rotation angle with respect to time.

A curve 73 shown in (c) of the figure is a curve showing the time characteristic of the angular acceleration (rad / sec ² ) obtained by further differentiating the time characteristic of the angular velocity with time.

The curve 74 shown in FIG. 6 shows the rotation angle characteristic of the torque (N · m) obtained by multiplying the value of the angular acceleration shown by the curve 73 by the inertia (mass) of the rotor 1. It is a curve shown in the rotation angle range from rad to π rad (180 degrees) (corresponding to the time until the angular velocity indicated by T in Fig. 5 reaches a peak).

By integrating this torque value in the rotation angle range from the measured rotation angle of 0 rad to π rad, the energy due to the rotation of motor 1 at the time of π rad rotation at the end of this angle range is obtained. Can be calculated. This is represented by the area of the hatched area in FIG. The portion where the torque is above 0 indicates positive energy, and the portion below 0 indicates negative energy, and the difference indicates the magnitude of the energy at the time of _π rad rotation.

After that, the rotor 1 overshoots and stops at the position of the rotation angle π rad while repeating the slight forward and reverse rotation.

When the angular velocity measured at a certain point in time is ω and the moment of inertia of the rotating body 1 is I, the rotational energy 持つ of the rotating body 1 at that time is

Ε = (1/2) · I · ω ² can be calculated and displayed. As described above, according to the rotation information measuring device and the rotation information measuring method using the same, various kinds of rotation information for grasping the actual rotation state of the rotor of the two-pole step motor are brought into contact with the rotor. And therefore without affecting its rotational behavior Can be accurately measured over a range of rotation angles.

Next, a second specific embodiment of the present invention will be described.

In the above-described first embodiment, the light detecting elements 31 are arranged at intervals of 6 degrees in accordance with the movement of the rotor of the two-pole step motor, but the light detecting elements are arranged according to the movement of the rotating body. Thus, various applications are possible. For example, it is possible to grasp the movement of the hands of the clock.

Paying attention to the second hand that performs step hand movement, the second hand rotates 6 degrees per step, but since it is moving for less than 1 Oms, it has conventionally been possible to accurately determine the unsteady hand movement situation. I couldn't figure out. However, if the rotation information measuring device and the rotation information measuring method according to the present invention are used, it is possible to grasp the hand movement status while the second hand is actually moving.

Therefore, the tip of the second hand shaft is formed on a slope inclined with respect to the rotation axis, and a micro mirror is installed as a light reflecting member there to form a reflecting surface. For example, gold (Au) is vapor-deposited on a 100 micron thick Si surface, and then cut into a size of 100 microns vertically and horizontally as a micromirror.

At this time, the weight of the micromirror is approximately 2.3 / z g, and the weight ratio of the fourth wheel and the second hand together is approximately 8 mg, but the weight ratio is at most less than 0.1%. Therefore, the effect on the rotation behavior of the second hand axis by attaching the micro mirror can be neglected.

In this embodiment, instead of each photodetector 32 of the reflected light detection means 3 in the first embodiment, a sweep plane of the reflected light by the micromirror centered on the rotation axis of the second hand axis is used. Then, as shown in FIG. 7, a photodiode array 37 in which a plurality of photodiodes 37a are formed is arranged on the same circumference as shown in FIG.

By using this photodiode array 37, a large number of photodetectors such as photodiodes 3 can be set within a narrow range of 6 degrees, which is the rotation angle of the second hand in one step. 7a can be arranged, and as a result, it is possible to grasp the hand movement in a narrow angle area with sufficient accuracy.

The photodiode array 37 used as the reflected light detecting means has a shape as shown in Fig. 7, and a photodiode 37a of 5 mm in length and 0.8 mm in width has a pitch of 1 mm in the horizontal direction. This is a configuration in which 35 elements are aligned.

Even when using a photodiode array 37 in which a large number of photodiodes 37a are arranged in a plane as described above, since the angle range in which reflected light is received is as narrow as 6 degrees, any photodiode The light receiving surface of 37a has almost the same distance from the reflecting surface, and there is no problem in accuracy.

Next, a third specific embodiment of the present invention will be described.

FIG. 8 is a side view showing the rotation information measuring device together with a rotating body as an object to be measured. In this embodiment, the tip of the rotating shaft 1a of the rotating body 1 has an inclination angle およそ of about 85 degrees with respect to the rotating axis 1c of the rotating body 1 (with respect to a plane orthogonal to the rotating axis 1c. The reflection surface 1b was formed so as to have an inclination of about 5 degrees. Due to this inclination, the reflected light LR from the reflecting surface 1b is caused by the rotation of the rotating body 1 at an angle of about 10 degrees with respect to the laser beam LB irradiated from the light beam irradiation means 2 along the rotation axis 1c. It rotates and forms a conical sweep surface.

The light beam irradiating means 2 is composed of a semiconductor laser, a condenser lens, and the like, similarly to the first embodiment shown in FIG.

As a reflected light detecting means, an annular photodiode array 38 as shown in FIG. 9 was arranged so as to surround the light beam irradiating means 2. The toroidal photodiode array 38 is a plurality of photodetectors that are equally divided in the circumferential direction by a straight line radiating from the center of the torus on the surface of a toroidal Si wafer. It forms a photodiode 38a.

By arranging the photodiodes 38a in an annular shape in this way, Measurement of time information. In the annular photodiode array 38 in this embodiment, a reference circle passing through the center of each photodiode 38a has a radius of 30 mm, an element pitch is 3.1 mm, and 60 elements are arranged in a circle. It is arranged in the direction.

The light beam irradiating means 2 can be united by aligning the laser beam irradiating optical axis with the central axis of the annular photodiode array 38 and integrally combining them. By doing so, there is no need to adjust the positional relationship between the light beam irradiating means 2 and the light detecting element, which was required in the first and second embodiments.

However, the distance between the integrated light beam irradiation means 2 and the annular photodiode array 38 and the reflecting surface 1b on the rotation axis 1a is determined by the reflected light LR. It is necessary to make adjustments so that the light enters each photodiode 38 a of the annular photodiode array 38.

In this way, by bringing the reflected light detecting means closer to or integrated with the light beam irradiating means, the space required by the rotation information measuring device is reduced, and the device can be downsized. Further, when it is difficult to move the rotating body as the object to be measured, it becomes possible to carry the rotation information measuring device and perform the measurement.

Furthermore, the direction of light beam irradiation by the light beam irradiation means can be easily set not only vertically but also horizontally or at an arbitrary angle.

Here, a circuit configuration example of a portion corresponding to the rotation angle time information measuring means 4 and the storage means 5 in FIG. 1 used in the third embodiment will be described with reference to FIG. In this embodiment, the rotation angle time information measuring means 4 includes a binarizing circuit group 41, a parallel / serial converter 42, and a counter 43. The storage means 5 is constituted by a decoder 50 and a memory 51 such as a RAM.

Each of the photodiodes 38a of the annular photodiode array 38 and the reflected light LR from the reflection surface 1b of the rotation axis 1a when the rotating body 1 shown in FIG. The detection signal S d that is output by receiving light is Binarization circuit (comprising a comparator) 4 1a Binarizes with a and converts it to pulse signal Pd.

Each of the detection signals S d of channels CH 1 to CH 60 by 60 photo diodes 38 a is binarized by each binarization circuit 41 a of the binarization circuit group 41 and is sequentially timed. The parallel pulse signal Pd, which is shifted, is input to a parallel-serial converter (constituted by an OR circuit) 42 via all individual signal lines, where it is converted to a serial pulse signal Ps.

FIG. 11 shows the relationship between the parallel pulse signal Pd and the serial pulse signal Ps. In this example, the parallel pulse signals Pd1 to Pd60 by the 60 signal lines of the channels CH1 to CH60 are converted into a serial pulse signal Ps by one signal line.

This serial pulse signal Ps is input to the trigger terminal of a counter 43 for measuring time, which counts clock pulses cp.

The counter 43 is used to start the rotation of the rotating body 1 shown in FIG. 8 (the time at which a drive pulse is output from the drive circuit 8 in FIG. 1) or the first falling edge of the serial pulse signal Ps. (These are referred to as “reference points.”) With the trigger as a trigger, the count value is reset and the count operation of the clock pulse cp is started. Then, with the rising edge and the falling edge of the serial pulse signal Ps as a trigger, the count value at that time is output and stored in the memory 51. This count value corresponds to the elapsed time from the reference time or the rotation time of the rotating body 1.

At this time, the decoder 50 simultaneously determines which of the photodiodes 38 a in the ring-shaped photodiode array 38 the triggering pulse was a pulse based on the detection signal Sd. Therefore, the pulse signal Pd from each binarization circuit 41 a of the binarization circuit group 41 is input to the decoder 50, similarly to the input to the parallel-serial converter 42, and an annular photo diode is input. For the photodiode array Output an identification code indicating the element number of the node 38a to the memory 51. In this example, a 6-bit binary signal was used as the identification code.

Therefore, the data stored in the memory 51 is a total of three types: an identification code from the decoder 50, a code for distinguishing the rising and falling of the serial pulse signal Ps, and a count value from the counter 43. Each time a rising or falling edge of the serial pulse signal Ps occurs, three new types of data are stored in the memory 51. By doing so, the amount of data to be stored can be significantly reduced.

Even if the count value of the power counter 43 is stored only at one of the rising edge and the falling edge of the serial pulse signal Ps, the rotation time information for each constant rotation angle can be obtained. However, if the count value of the counter 43 is stored at both the rising edge and the falling edge, the reflected light is reflected at the center of each photodiode 38a by averaging the count values. It is possible to calculate rotation time information up to the point of receiving light.

The calculation method of the angular velocity, the angular acceleration, the torque, and the energy by the calculating means 6 thereafter is the same as in the above-described embodiment.

In the circuit shown in FIG. 10, the number of the binarizing circuits constituting the binarizing circuit group 41 is adjusted to the number of the light detecting elements constituting the reflected light detecting means 3 to thereby realize the first circuit. It can also be used as the rotation angle time information measuring means and the storage means of the second embodiment.

The accuracy of the torque and energy measured by each embodiment of the present invention largely depends on the accuracy of the moment of inertia of the rotating body. Considering component tolerances and eccentricity during rotation, it is estimated that the measured values have an accuracy of about ± 5% or less.

Three specific embodiments of the present invention have been described. Various combinations or changes are possible without being limited to those shown in the above embodiment, such as the angle range and the method of processing the time information.

According to the present invention, it is possible to quantitatively measure the operating state of a small rotating body during rotation, which could not be accurately grasped in the past, and to evaluate the performance of the rotating body. In the case of a step motor, the input energy can be calculated from the applied current and voltage, and the efficiency of the actual motor as a motor can be determined from the comparison with the measured rotational energy of the rotor. Errors and variations in characteristics can be confirmed as future development guidelines.

Regarding the movement of the hands of the clock, the difference between the current hand movement and the current situation is clearly clarified, and future development guidelines can be obtained.

The method and apparatus for measuring rotation information of a rotating body according to the present invention are particularly useful for measuring small torque and energy, which cannot be measured conventionally, and for measuring rotation information for a rotating body that moves in an unsteady manner. It is valid. As an application example other than the above, it is also applicable to an absolute encoder or a wow and flutter / jitter measuring instrument. Industrial applicability

According to the method and apparatus for measuring rotation information of a rotating body according to the present invention, rotation information such as a minute torque and a minute energy of a small rotating body that cannot be accurately measured in the past can be obtained by rotating the rotating information. It can be measured in a non-contact manner without affecting the rotation behavior of the body, and is particularly effective for measurement when the rotating body moves in an unsteady manner.

In addition, measurement can be performed under the condition that the rotating body is actually moving, and as a result, various kinds of rotation information can be obtained quantitatively. There are many unprecedented advantages, such as clear future development guidelines.

Claims

The scope of the claims

1. At the tip of the rotating shaft of the rotating body as the object to be measured, a reflecting surface inclined with respect to the rotating axis is formed.

Irradiating a light beam on a reflecting surface of the rotating body from a direction along the rotation axis, and after starting rotation of the rotating body, light reflected by the reflecting surface is predetermined on the same circumference around the rotation axis. By detecting with a plurality of light detecting elements installed at an angular interval, the elapsed time from the reference time to the detection of the reflected light by each of the plurality of light detecting elements is determined by the rotation of the rotating body. A method for measuring rotation information of a rotating body, characterized in that it is measured as angular time information.

2. A method for measuring the angular velocity of a rotating body, which is characterized by measuring the angular velocity of the rotating body by differentiating the time information of the rotating angle measured by the method for measuring rotation information of the rotating body according to claim 1 with respect to time. Rotation information measurement method.

3. The rotation information measurement of the rotating body, wherein the angular acceleration measured by the method for measuring rotation information of the rotating body according to claim 2 is further differentiated by time to measure the angular acceleration of the rotating body. Method.

4. Multiplying the angular acceleration measured by the method for measuring rotation information of a rotating body according to claim 3 by an inertia moment of the rotating body to measure a torque acting on the rotating body. Characteristic method of measuring rotation information of rotating body.

5. The end of the rotation angle range by integrating the torque measured by the method for measuring rotation information of the rotation body according to claim 4 with the rotation angle range in which the torque is measured after the rotation of the rotation body is started. And measuring the rotation energy of the rotating body.

6. Assuming that the angular velocity at a certain point in time measured by the method for measuring rotation information of a rotating body according to claim 2 is ω, and the moment of inertia of the rotating body is I, the rotational energy of the rotating body at the time is Ε Is obtained by calculating E = (l 2) · Ι · ω ² and measuring the rotation information of the rotating body.

7. A rotating body having a reflecting surface formed at the tip of a rotating shaft inclined with respect to the rotating axis as a measurement target, and a device for measuring rotation information of the rotating body,

Light beam irradiation means for irradiating the reflection surface of the rotating body with a light beam from a direction along the rotation axis;

Reflected light detecting means comprising a plurality of light detecting elements arranged so as to detect light reflected by the reflecting surface at predetermined angular intervals on the same circumference centered on the rotation axis, and

After the rotation of the rotator is started, the reflected light from the reflecting surface is detected by the plurality of photodetectors, so that the reflected light is detected by the plurality of photodetectors from a reference time. Means for measuring elapsed time as time information of the rotation angle of the rotating body,

A rotation information measuring device for a rotating body, comprising:

8. An angular velocity calculating means for calculating the angular velocity of the rotating body by differentiating the time information of the rotating angle measured by the rotating body rotation information measuring device according to claim 7 with respect to time is provided. Characteristic device for measuring rotation information of rotating body.

9. An angular acceleration calculating means for calculating an angular acceleration of the rotating body by differentiating the angular velocity measured by the rotating body rotation information measuring device according to claim 8 with time further. A rotation information measuring device for a rotating body.

10. A torque for calculating a torque acting on the rotating body by multiplying the angular acceleration measured by the rotating information measuring device of the rotating body by an inertia (mass) of the rotating body. Measurement of rotation information of a rotating body, characterized by having a calculation means

11. The torque measured by the rotation information measurement device for a rotating body according to claim 10 is integrated by the torque within a measured rotation angle range after the rotation of the rotating body is started, thereby obtaining the rotation. A rotation information measuring device for a rotating body, comprising: an energy calculating means for calculating a rotation energy of the rotating body at the end of the angle range.

12. The rotational body at the time point has the angular velocity ω at a certain point in time measured by the rotation information measuring device of the rotary body according to claim 8 and the moment of inertia of the rotary body from I. An apparatus for measuring rotation information of a rotating body, comprising energy calculation means for calculating the energy of rotation Ε by calculating E = (l 2) · ·· ω ² .

13. The rotation information measuring device for a rotating body according to claim 7,

A rotation information measuring device for a rotating body, comprising a driving unit for rotating the rotating body.

14. The rotation information measuring device for a rotating body according to claim 10, wherein:

A rotation information measuring device for a rotating body, further comprising a display unit for displaying the torque calculated by the torque calculation unit.

15. The rotation information measuring device for a rotating body according to claim 11, wherein:

A rotation information measuring device for a rotating body, further comprising a display means for displaying the energy calculated by the energy calculating means.

16. In the rotation information measurement device for a rotating body according to claim 12,

A rotation information measuring device for a rotating body, further comprising a display unit for displaying the energy calculated by the energy calculating unit.