JP7100677B2 - Test system - Google Patents

Description

The present invention mainly relates to a technique for testing an automobile.

As a technology for testing automobiles, in a test system in which the output shaft of the engine of an automobile is connected to a dynamometer via a torque sensor, the rotation speed of the engine or dynamometer is detected by a rotary meter, and the rotation speed or torque sensor is used. Techniques for testing various characteristics of an engine while controlling the operation of a dynamometer or an engine according to the detected torque are known (for example, Patent Documents 1 and 2).

Further, as a tachometer of such a test system, an optical or magnetic rotary encoder (for example, Patent Documents 3 and 4) that outputs a detection signal corresponding to one cycle corresponding to a rotation of a predetermined angle is used. A tachometer that detects the rotation speed by counting the cycle of the detection signal output by the encoder per unit time is widely used.

Japanese Unexamined Patent Publication No. 2018-17591 Japanese Unexamined Patent Publication No. 2018-17589 Japanese Unexamined Patent Publication No. 2010-145333 Japanese Unexamined Patent Publication No. 2018-132359

Since the electric motor can generate a large torque even in the low rotation speed range, it is important to test in the low rotation speed range in the electric vehicle and the hybrid vehicle.
However, the existing test system that has been used for testing automobiles using an engine requires a rotation speed in the low rotation speed range due to the low importance of the test in the low rotation speed range where the torque generated by the engine is small. It may not have a tachometer that can measure with resolution. For example, in the case of a tachometer using a rotary encoder in which the number of detection signal cycles per rotation is 600, when the rotation speed is 5 r / min, the detection signal cycle is 20 ms, and the rotation speed is set at shorter time intervals. Cannot measure and process.

When testing the low rotation speed range of an automobile using an electric motor using such an existing test system, it is necessary to replace or add to a rotary encoder with higher resolution, but the cost of replacement and The work load is heavy, and it may not be possible to replace or add due to space problems.

An object of the present invention is to measure the rotation speed using a detection signal corresponding to one cycle of rotation at a predetermined angle at a time interval shorter than the cycle of the detection signal.
Another object of the present invention is to realize such measurement of rotation speed by changing the structure of an existing test system with a relatively simple structure.
Another object of the present invention is to measure the rotation speed in a wide rotation speed range with a relatively simple configuration.

In order to achieve the above-mentioned problems, the present invention appears in a test system for testing a test body having a rotating shaft with a rotating disk rotating with the rotating shaft and one rotation of the rotating disk with the rotation of the rotating disk. From signal A and signal B using a signal generation means that generates a signal A that is a periodic signal having n periods and a signal B that is a periodic signal whose phase is 90 degrees different from that of the signal A, and an atan2 function. With the rotation of the turntable in the predetermined rotation direction, the rotation angle of the turntable in the predetermined rotation direction from -π to + π in a cycle having the same time length as the cycle of the signal A and the signal B. Ω1 = dθ1 (t) / dt and ω2 = dθ2 (t) / dt are calculated by generating an angle signal θ1 and an angle signal θ2 that repeat the increase proportional to the increase with a positive proportional coefficient in different phases. The angle signal θ2 changes from + π to -π, not including the period during which the angle signal θ1 changes from + π to -π when the differential signal generation means and the rotating disk are rotating in the predetermined rotation direction. Ω is calculated by setting ω1 to ω in the first period including the period including the period, and ω2 in the second period excluding the first period, and calculating the angular velocity ωd1 of the rotating disk. (Rad / s) is provided with an angular velocity calculation means for calculating (rad / s) by ωd1 = ω / n.

The atan2 function is a function that obtains the arctangent from the xy coordinates in radian units. As x0 and y0, atan2 (y, x) is a half from the origin to the point (x, y) in the Euclidean plane. Gives the angle in radians between the straight line and the positive x-axis.

Here, in this test system, it is assumed that the signal A is 90 degrees ahead of the signal B, and in the differential signal generation means, atan2 (B, A), atan2 (-B, -A), atan2 ( The angle signal θ1 and the angle signal θ2 are generated by using any one of -A, B) and atan2 (A, -B) as the angle signal θ1 and the other one as the angle signal θ2. You can do it.

Further, in order to achieve the above-mentioned problem, the present invention has a test system for testing a test body having a rotating shaft, a rotating disk that rotates together with the rotating shaft, and one rotation of the rotating disk with the rotation of the rotating disk. A signal A and a signal using an atan2 function and a signal generation means for generating a signal A which is a periodic signal having n periodic appearances and a signal B which is a periodic signal whose phase is 90 degrees different from that of the signal A. From B, with the rotation of the turntable in the predetermined rotation direction, the cycle of the same time length as the cycle of the signal A and the signal B, from + π to -π, in the predetermined rotation direction of the turntable. Ω1 = -d θ1 (t) / dt, ω2 = -d θ2 (t) / The differential signal generation means for calculating dt and the angle signal θ2 from -π excluding the period during which the angle signal θ1 changes from -π to + π when the rotating disk is rotating in the predetermined rotation direction. Ω is calculated by setting ω1 to ω in the first period including the period changing to + π, and ω2 in the second period excluding the first period, and the rotation. It is equipped with an angular velocity calculating means for calculating the angular velocity ωd1 (rad / s) of the board by ωd1 = ω / n.

Here, in this test system, it is assumed that the signal A is 90 degrees ahead of the signal B, and in the differential signal generation means, atan2 (-B, A), atan2 (B, -A), atan2 ( The angle signal θ1 and the angle signal θ2 are generated by using any one of A, B) and atan2 (-A, -B) as the angle signal θ1 and the other one as the angle signal θ2. You can do it.

According to such a test system, the measurement of the rotation speed performed by using the detection signal corresponding to the rotation of a predetermined angle in one cycle can be performed at a time interval shorter than the cycle of the detection signal.
Here, in the above test system, the rotary disk is assumed to have the n convex portions arranged in the circumferential direction, and the signal generation means is magnetically accompanied by the movement of the convex portions due to the rotation of the rotary disk. It may be provided with two magnetic sensors arranged in different phases with respect to the convex portion so as to detect each of the two detection signals used as the signal A and the signal B by the change.

Alternatively, in the above test system, the rotary disk is assumed to have the n convex portions arranged in the circumferential direction, and the signal generation means is magnetically changed due to the movement of the convex portions due to the rotation of the rotary disk. As described above, four detection signals A *, B *, A ~ *, and B ~ * whose phases are sequentially shifted by 90 degrees, in which one cycle appears each time the turntable rotates by an angle φ, are detected. It is equipped with four magnetic sensors arranged with different phases with respect to the convex portion, and a signal calculation means for calculating the signal A and the signal B from A = A * -A ~ * and B = B * -B ~ *. It may be a thing.

According to these test systems, if the existing test system includes a member in which n convex portions are arranged in the circumferential direction that rotates with the rotation axis of the test piece, the member is diverted to the turntable. Then, by simply arranging the magnetic sensor for the member so that the required detection signal can be obtained, the rotation is performed using the detection signal in which one cycle corresponds to the rotation of a predetermined angle. The speed can be measured at a time interval shorter than the period of the detection signal.

Further, even when the existing test system does not have a member in which n convex portions are arranged in the circumferential direction to rotate with the rotation axis of the test body, the turntable is rotated with the rotation axis of the test body. In addition, it is sufficient to change the structure by simply arranging the magnetic sensor for the member so that the required detection signal can be obtained.

Further, in the test system equipped with these magnetic sensors, the angular velocity ωd2 (rad / s) of the rotating disk is calculated by dividing the number of cycles per unit time of the detection signal detected by the magnetic sensor by the n. One of the second angular velocity calculation means, the angular velocity ωd1 (rad / s) calculated by the angular velocity calculation means, and the angular velocity ωd2 (rad / s) calculated by the second angular velocity calculation means is output as the angular velocity ωd of the rotary disk. A switching means may be provided. When the angular velocity ωd becomes larger than the first threshold value when the angular velocity ωd1 (rad / s) calculated by the angular velocity calculating means is output as the angular velocity ωd of the turntable. , The angular velocity ωd of the rotating disk to be output is switched to the angular velocity ωd2 (rad / s) calculated by the second angular velocity calculating means, and the angular velocity ωd2 (rad / s) calculated by the second angular velocity calculating means of the rotating disk. When the angular velocity ωd is output as the angular velocity ωd and the angular velocity ωd becomes equal to or less than the second threshold value which is the threshold value equal to or less than the first threshold value, the angular velocity ωd of the rotating disk to be output is calculated. It switches to the angular velocity ωd1 (rad / s) calculated by the angular velocity calculation means.

By doing so, in a higher speed rotation speed range where the angular velocity calculation means cannot correctly measure the angular velocity ωd1 (rad / s), it is calculated from the number of cycles per unit time of the detection signal by the second angular velocity calculation means. Since the angular velocity ωd2 (rad / s) is used as the angular velocity ωd of the rotating disk, the rotational velocity can be accurately measured in a wide rotational velocity range by a relatively simple configuration in which the magnetic sensor is shared for the measurement of the angular velocity ωd1 and the angular velocity ωd2.

Further, when the test system includes a dynamometer, a torque sensor that connects the shaft of the dynamometer and the rotation shaft of the test piece, and the torque sensor includes a disk having a plurality of teeth formed on the outer periphery thereof. , This disk may be diverted as the rotary disk in the form of using the teeth as the convex portion.

By doing so, it is possible to easily construct a test system capable of measuring the rotation speed in the low rotation speed range simply by arranging the magnetic sensor on the disk of the torque sensor.
Here, the test body is, for example, an automobile engine, an electric motor (power unit) of an electric vehicle, an automobile power train component such as a transmission or a drive shaft, or an automobile power train, or an automobile.

As described above, according to the present invention, the measurement of the rotation speed performed by using the detection signal corresponding to the rotation of a predetermined angle in one cycle can be performed at a time interval shorter than the cycle of the detection signal.
Further, according to the present invention, such measurement of the rotation speed can be realized by changing the structure relatively simply with respect to the existing test system.
Further, according to the present invention, the rotation speed can be measured in a wide rotation speed range with a relatively simple configuration.

It is a figure which shows the structure of the test system which concerns on embodiment of this invention. It is a figure which shows the arrangement of the magnetic sensor which concerns on embodiment of this invention. It is a block diagram which shows the structure of the measurement control system which concerns on embodiment of this invention. It is a block diagram which shows the structure of the low-speed region rotation speed calculation part which concerns on embodiment of this invention. It is a figure which shows the operation of the low-speed region rotation speed calculation part which concerns on embodiment of this invention. It is a flowchart which shows the switching process which concerns on embodiment of this invention. It is a figure which shows the other structural example of the test system which concerns on embodiment of this invention.

Hereinafter, embodiments of the present invention will be described.
FIG. 1 shows the configuration of the test system according to the present embodiment.
The test body is a system for testing the test body 100, and the test body 100 is an engine of an automobile, an electric motor (power unit) of an electric vehicle or a hybrid vehicle, a transmission, a drive shaft, or a combination thereof. ..

As shown in the figure, the test system includes a dynamometer 1, a flange-shaped torque sensor 2, a shaft 3, an intermediate bearing 4, a turntable 5, a frame 6, four magnetic sensors 7, and a measurement control system 8.

The rotating shaft of the dynamometer 1 is connected to one end of the shaft 3 via the torque sensor 2, and the other end of the shaft 3 is connected to the output shaft of the test piece 100. Further, the intermediate bearing 4 pivotally supports the shaft 3 so that a load in the non-rotational direction is not applied to the output shaft of the test piece 100.

The torque sensor 2 is fixed to the rotating shaft of the dynamometer 1 and rotates with the rotation of the dynamometer 1, and detects the torque acting between the shaft 3 and the rotating shaft of the dynamometer 1.

The measurement control system 8 controls the dynamometer 1 and the test body 100 to execute a predetermined measurement sequence, and measures various states of the test body 100.
Further, the turntable 5 is fixed to the torque sensor 2 and rotates together with the torque sensor 2. The four magnetic sensors 7 are, for example, magnetic resistance sensors, each of which is fixed to the frame 6 so as to be located around the rotating disk 5, and detects a magnetic change accompanying the rotation of the rotating disk 5.

Here, FIG. 2a shows the positional relationship between the rotating disk 5 and the four magnetic sensors 7 as viewed in the axial direction.
As shown in the figure, the turntable 5 has a gear-like shape in which the outer periphery is a large number of teeth (convex portions) arranged in the circumferential direction.
Then, the magnetism acting on each magnetic sensor 7 changes periodically due to the movement of the teeth due to the rotation of the turntable 5, and each magnetic sensor 7 outputs a detection signal that changes periodically. When a magnetic resistance sensor is used as the magnetic sensor 7, the magnetism acting on the ferromagnetic material of the magnetic resistance sensor changes periodically due to the movement of the teeth due to the rotation of the rotating disk 5, and the detection changes periodically. A signal is output.

Here, when the test system according to the present embodiment is constructed by using the existing test system, the existing test system is a member having convex portions arranged in the circumferential direction, which rotates with the rotation of the dynamometer 1. If possible, this member is diverted as the turntable 5.

For example, if the torque sensor 2 of the existing test system already has a gear-shaped member that rotates with the torque sensor 2 for rotation detection of the torque sensor 2, four members are provided around the member. By arranging the magnetic sensor 7 using the frame 6, it can be diverted as the rotating disk 5.

Next, the four magnetic sensors 7 are arranged around the turntable 5 so that the four detection signals A *, B *, A ~ *, and B ~ * whose phases are sequentially shifted by 90 degrees can be obtained. ..
That is, as shown in FIG. 2b1, the central angle of one tooth pitch of the rotary disk 5 with respect to the center of the rotary disk 5 is φ, and the angle of the arrangement position of the magnetic sensor 7 that outputs the detection signal A * is 0 degree. As shown in FIG. 2b2, the magnetic sensor 7 outputs the detection signals B to * with k as an arbitrary integer, assuming that the angle is measured around the center of the board 5 in the direction opposite to the rotation direction DR (counterclockwise in the figure). The angle of the placement position is kφ + (φ / 4), the angle of the placement position of the magnetic sensor 7 that outputs the detection signals A to * is kφ + (2φ / 4), and the placement of the magnetic sensor 7 that outputs the detection signal B * Arrange so that the position angle is kφ + (3φ / 4).

In FIGS. 2b1-b2, the shape of the teeth of the turntable 5 is represented by a rectangular shape, but in reality, the shape of the teeth of the turntable 5 is an involute curve.
By arranging each magnetic sensor 7 in this way, as shown in FIG. 2c, four sinusoidal detection signals A *, B *, A ~ *, and B ~ * can be obtained as the rotating disk 5 rotates. .. Further, the detection signal B * has a -90 degree phase difference with respect to the detection signal A *, the detection signals A to * have a -180 degree phase difference with respect to the detection signal A *, and the detection signals B to * have a detection signal A. The phase is different by -270 degrees with respect to *. Further, the time length of one cycle of the detection signals A *, B *, A ~ *, and B ~ * is the same angle as the central angle φ of one tooth pitch, and the time length required for the rotating disk 5 to rotate. That is, the time length is one-third of the time required for the turntable 5 to make one rotation.

Next, FIG. 3 shows the configuration of the measurement control system 8.
As shown in the figure, the measurement control system 8 includes a rotation speed detection unit 81, an operation control unit 82, and a measurement processing unit 83.
The rotation speed detection unit 81 calculates the rotation speed ωd of the dynamometer 1 / test piece 100 from the detection signals A *, B *, A ~ *, and B ~ * output by the magnetic sensor 7, and together with the operation control unit 82. It is output to the measurement processing unit 83.

The operation control unit 82 controls the operation of the test body 100 and the dynamometer 1 according to the rotation speed ωd output from the rotation speed detection unit 81, the torque detected by the torque sensor 2, and the like, and a predetermined measurement sequence. To execute. The measurement processing unit 83 measures a predetermined characteristic of the test body 100 from the rotation speed ωd output from the rotation speed detection unit 81, the torque detected by the torque sensor 2, the control state of the operation control unit 82, and the like.

Next, the rotation speed detection unit 81 includes a low-speed range rotation speed calculation unit 811, a rotation speed calculation unit 812, and a switching processing unit 813.
The low-speed range rotation speed calculation unit 811 calculates the rotation speed of the dynamometer 1 / test piece 100 as the rotation speed ωd1 using the detection signals A *, B *, A ~ *, and B ~ * output by the magnetic sensor 7. The rotation speed calculation unit 812 calculates the rotation speed of the dynamometer 1 / test piece 100 as the rotation speed ωd2 using the detection signals A *, B *, A ~ *, and B ~ * output by the magnetic sensor 7.

The switching processing unit 813 selectively selects one of the rotation speed ωd1 calculated by the low-speed range rotation speed calculation unit 811 and the rotation speed ωd2 calculated by the rotation speed calculation unit 812, and rotates the dynamometer 1 / test piece 100. Switching processing is performed to output to the operation control unit 82 and the measurement processing unit 83 as the speed ωd. This switching process will be described later.

Next, FIG. 4 shows the configuration of the low-speed range rotation speed calculation unit 811.
As shown in the figure, the low-speed range rotation speed calculation unit 811 has four signal adjustment units 8111 corresponding to each of the four detection signals A *, B *, A ~ *, and B ~ * output by the four magnetic sensors 7. The first signal generation unit 8112, the second signal generation unit 8113, the first angle signal calculation unit 8114, the second angle signal calculation unit 8115, the differential signal calculation unit 8116, and the rotation speed conversion unit 8117 are provided.

Corresponding detection signals are input to the four signal adjustment units 8111 from the four magnetic sensors 7, and each signal adjustment unit 8111 adjusts the gain and offset of the input detection signals, and then sets the detection signal to a predetermined sampling frequency. Detection signal A *'adjusted with A *, detection signal B *'adjusted with B *, detection signal A ~ *'adjusted with A ~ *, detection signal adjusted with B ~ * Output B ~ *'.

The first signal generation unit 8112 uses the detection signal A *'and the detection signals A ~ *'output from the signal adjustment unit 8111 to generate the signal A by A = A *'-A ~ *', and the first signal generation unit 8112 generates the signal A. 2 The signal generation unit 8113 uses the detection signal B *'output from the signal adjustment unit 8111 and the detection signals B ~ *'to generate the signal B by B = B *'-B ~ *'.

As shown in FIG. 5a, the detection signal A *'and the detection signal A ~ *'are 180 degrees different in phase, and the detection signal B *'and the detection signal B ~ *'are 180 degrees different in phase. In addition, the signal A is a signal having the same phase as the detection signal A *'and having a double amplitude, and the signal B is a signal having the same phase as the detection signal B *'and having a double amplitude.

Further, as shown in FIG. 2a, the magnetic sensor 7 that outputs the detection signal A * and the magnetic sensor 7 that outputs the detection signals A to * are arranged at positions substantially opposite to the center of the rotary disk 5. By arranging the magnetic sensor 7 that outputs the detection signal B * and the magnetic sensor 7 that outputs the detection signals B to * at positions approximately opposite to the center of the rotating disk 5, the phase is 180. By A = A *'-A ~ *', which is the subtraction of the detection signals A *'and the detection signals A ~ *', the influence of the eccentricity of the rotating disk 5 on the signal A is canceled and the phases differ by 180 degrees. By B = B *'-B ~ *', which is the subtraction of the detection signal B *'and the detection signal B ~ *', the influence of the eccentricity of the rotating disk 5 on the signal B is canceled.

Further, since the detection signal A *'is 90 degrees ahead of the detection signal B *', the signal A is a signal whose phase is 90 degrees ahead of the signal B, and the signals A and B are the cos signal and the sin signal. There is a relationship.
The first angle signal calculation unit 8114 generates the first angle signal θ1 from the signal A and the signal B by θ1 = atan2 (B, A), and the second angle signal calculation unit 8115 from the signal A and the signal B. The second angle signal θ2 is generated by θ2 = atan2 (-A, B). As described above, as x0 and y0, atan2 (y, x) is a radian unit between the half-line from the origin to the point (x, y) in the Euclidean plane and the positive x-axis. Give an angle.

As shown in FIG. 5c, the first angle signal θ1 and the second angle signal θ2 become signals that repeatedly increase from -π to + π, and in each cycle of increasing from -π to + π, the first angle signal θ1 and the second angle signal θ2. The values of the angle signal θ1 and the second angle signal θ2 increase in proportion to the increase in the angle of rotation of the turntable 5. Further, the first angle signal θ1 and the second angle signal θ2 are out of phase by 90 degrees.

The differential signal calculation unit 8116 calculates the differential signal ω1 obtained by time-differentiating the first angle signal θ1 by ω1 = dθ1 (t) / dt, and ω2 = dθ2 (the differential signal ω2 obtained by time-differentiating the second angle signal θ2). Calculated by t) / dt.

Further, the differential signal calculation unit 8116 calculates the differential signal ω by setting the differential signal ω1 to ω when −π <θ1 <0 and the differential signal ω2 to ω when 0 ≦ θ1 ≦ π. do.
In this way, both the differential signal ω1 and the differential signal ω2 are obtained and switched to be used as the differential signal ω. As shown in FIG. 5d, the first angle signal θ1 of the differential signal ω1 changes from + π to -π. Since the differential signal ω2 takes a large negative value when the second angle signal θ2 changes from + π to -π, this value part should not be used as the differential signal ω. To make it.

Therefore, the part of the value when the first angle signal θ1 of the differential signal ω1 changes from + π to -π and the part of the value when the second angle signal θ2 of the differential signal ω2 changes from + π to -π. If is not used, the differential signal ω1 and the differential signal ω2 may be switched arbitrarily. That is, the first period is an arbitrary period including the period in which the first angle signal θ1 changes from + π to -π and the second angle θ2 changes from + π to -π. May have ω1 as ω, and ω2 may be ω in the second period, which is the period excluding the first period.

The differential signal ω calculated in this way represents the angular velocity calculated by regarding the rotation of the same angle as the central angle φ of one tooth pitch of the rotating disk 5 as one rotation.
Then, the rotation speed conversion unit 8117 converts the angular velocity ω / n of the rotary disk 5 obtained by dividing the differential signal ω calculated by the differential signal calculation unit 8116 by the number of teeth n of the rotary disk 5 into r / min. The calculated rotation speed ωd1 is calculated by ωd1 = (ω / n) × (60 / 2π) and output to the switching processing unit 813.

The low-speed range rotation speed calculation unit 811 has been described above.
By the way, the detection signal is detected by the first angle signal calculation unit 8114 and the second angle signal calculation unit 8115 without providing the first signal generation unit 8112 and the second signal generation unit 8113 in the above low speed range rotation speed calculation unit 811. The first angle signal θ1 and the second angle signal θ2 may be calculated by using A * and B * as they are as the signals A and B.

Further, in the first angle signal calculation unit 8114 and the second angle signal calculation unit 8115 of the above low speed range rotation speed calculation unit 811, atan2 (B, A), atan2 (-B, -A), atan2 (-A, By setting any one of B) and atan2 (A, -B) as the first angle signal θ1 and the other one as the second angle signal θ2, the first angle signal θ1 and the second angle The signal θ2 may be generated. atan2 (B, A), atan2 (-B, -A), atan2 (-A, B), atan2 (A, -B) all repeat the increase from -π to + π in different phases. It becomes a signal.

However, also in this case, the portion of the value when the first angle signal θ1 of the differential signal ω1 changes from + π to -π in the differential signal calculation unit 8116 and the second angle signal θ2 of the differential signal ω2 are + π. The value used as ω is switched between the differential signal ω1 and the differential signal ω2 so that the part of the value when changing from to -π is not used.

For example, the first angle signal calculation unit 8114 generates the first angle signal θ1 by θ1 = atan2 (B, A), and the second angle signal calculation unit 8115 generates the first angle signal θ2 by θ2 = atan2 (-B, -A). A second angle signal θ2 whose phase is 180 degrees different from that of the angle signal θ1 is generated, and in the differential signal calculation unit 8116, the differential signal ω is set to ω when -0.5π <θ1 <+ 0.5π. It may be calculated by setting the differential signal ω2 to ω when + 0.5π ≤ θ1 ≤ -0.5π.

When the rotating disk 5 is rotated in the reverse direction, the first angle signal θ1 and the second angle signal θ2 are signals that repeatedly decrease from + π to −π in different phases.
Therefore, when the rotary disk 5 rotates in the reverse direction, the part of the value when the first angle signal θ1 of the differential signal ω1 changes from -π to + π and the second angle signal θ2 of the differential signal ω2 change from -π to + π. Even if the reverse rotation of the output shaft of the test piece 100 is measured by switching between the differential signal ω1 and the differential signal ω2 of the value used as ω so that the part of the value when changing to is not used. good.

Alternatively, when the rotating disk 5 is rotated in the reverse direction, the detection signal A * is replaced with B ~ *, the detection signal B * is replaced with A ~ *, the detection signal A ~ * is replaced with B *, and the detection signal B ~ * is replaced with A *. You may measure the reverse rotation of the output shaft of the test piece 100 by using the test piece 100.

Alternatively, in the first angle signal calculation unit 8114 and the second angle signal calculation unit 8115 of the above low speed range rotation speed calculation unit 811, atan2 (-B, A), atan2 (B, -A), atan2 (A, B) ) And atan2 (-A, -B) as the first angle signal θ1 and the other one as the second angle signal θ2, so that the first angle signal θ1 and the second angle The signal θ2 may be generated. atan2 (-B, A), atan2 (B, -A), atan2 (A, B), atan2 (-A, -B) all repeat the decrease from + π to -π in different phases. The values of the first angle signal θ1 and the second angle signal θ2 are proportional to the increase in the rotation angle of the rotating disk 5 with a negative proportional coefficient in each cycle in which the signal becomes a signal and decreases from + π to -π. Decrease.

However, in this case, in the differential signal calculation unit 8116, the differential signal ω1 is calculated by ω1 = -dθ1 (t) / dt, the differential signal ω2 is calculated by ω2 = -dθ2 (t) / dt, and the derivative is differentiated. The part of the value when the first angle signal θ1 of the signal ω1 changes from -π to + π and the part of the value when the second angle signal θ2 of the differential signal ω2 changes from -π to + π are not used. As described above, the value used as ω is switched between the differential signal ω1 and the differential signal ω2.

Further, in this case, when the rotating disk 5 is rotated in the reverse direction, the first angle signal θ1 and the second angle signal θ2 are signals that repeatedly increase from −π to + π in different phases. The part of the value when the first angle signal θ1 of the differential signal ω1 changes from + π to -π and the value when the second angle signal θ2 of the differential signal ω2 changes from + π to -π during reverse rotation. The reverse rotation of the output shaft of the test piece 100 may be measured by switching between the differential signal ω1 and the differential signal ω2 of the value used as ω so as not to use the portion of.

Alternatively, when the rotating disk 5 is rotated in the reverse direction, the detection signal A * is replaced with B ~ *, the detection signal B * is replaced with A ~ *, the detection signal A ~ * is replaced with B *, and the detection signal B ~ * is replaced with A *. You may measure the reverse rotation of the output shaft of the test piece 100 by using the test piece 100.

Returning to FIG. 3, the rotation speed calculation unit 812 is a detection signal A *, B *, A ~ *, B ~ * output by the magnetic sensor 7, or a signal A * -A ~ * or a signal. Using B * -B ~ * as a reference signal, the reference signal is pulsed, the number of pulses per unit time, that is, the number of cycles of the reference signal per unit time (frequency of the reference signal) is counted, and the counted number of pulses is counted. The rotation speed ωd2 obtained by dividing the angular speed by the number of teeth of the turntable 5 into r / min is calculated and output to the switching processing unit 813.

Next, the switching process performed by the switching process unit 813 will be described.
FIG. 6 shows the procedure of this switching process.
First, this switching process starts when the rotation of the dynamometer 1 / test piece 100 is stopped.
As shown in the figure, the switching processing unit 813 sets the rotation speed output as the rotation speed ωd to the operation control unit 82 and the measurement processing unit 83 to the rotation speed ωd1 calculated by the low speed region rotation speed calculation unit 811 in the switching processing. (Step 602).

Then, after starting the operation, the output rotation speed ωd is monitored, and if the rotation speed ωd exceeds the threshold value Th (step 604), it is output as the rotation speed ωd to the operation control unit 82 and the measurement processing unit 83. The rotation speed is switched to the rotation speed ωd2 output by the rotation speed calculation unit 812 (step 606).

The threshold value Th is, for example, according to the sampling theorem, the frequencies of the detection signals A *, B *, A to *, and B to * are the detection signals A *, in the signal adjustment unit 8111 of the low-speed rotation speed calculation unit 811. When the frequency is F / 2, which is half the sampling frequency F of B *, A ~ *, and B ~ *, the rotation speed ωd1 = {F / (2 × rotation disk 5) calculated by the low speed range rotation speed calculation unit 811. Number of teeth)} × (60 / 2π). Specifically, the threshold Th is slow, for example, when the frequencies of the detection signals A *, B *, A ~ *, B ~ * are 1/4 of the sampling frequency F, F / 4. It is assumed that the rotation speed ωd1 = {F / (4 × number of teeth of the rotating disk 5)} × (60 / 2π) calculated by the region rotation speed calculation unit 811.

Then, the output rotation speed ωd is monitored, and if the rotation speed ωd becomes less than the threshold value Th-M (step 608), the rotation speed is output to the operation control unit 82 and the measurement processing unit 83 as the rotation speed ωd. Is switched to the rotation speed ωd1 output by the low-speed range rotation speed calculation unit 811 (step 610).

Here, M is a constant for providing histeresis for switching between the rotation speed ωd1 and the rotation speed ωd2 of the rotation speed output as the rotation speed ωd as described above.
Then, the process returns to the monitoring process of step 604.
The switching process performed by the switching processing unit 813 has been described above.
According to such a switching process, the magnetic sensor 7 is shared by the low-speed range rotation speed calculation unit 811 and the rotation speed calculation unit 812, and the low-speed range rotation speed calculation unit 811 can correctly detect the rotation speed, but the rotation speed is calculated. In the low rotation speed range including the rotation speed range where the rotation speed cannot be detected correctly by the unit 812, the rotation speed ωd of the dynamometer 1 / test piece 100 is detected by using the low speed range rotation speed calculation unit 811, and the rotation speed in the low speed range is detected. Even in a higher rotation speed range where the calculation unit 811 cannot correctly detect the rotation speed, the rotation speed calculation unit 812 can be used to correctly detect the rotation speed ωd of the dynamometer 1 / test piece 100, which is wide. The rotation speed can be measured correctly in the rotation speed range.

The embodiment of the present invention has been described above.
As described above, according to the present embodiment, the measurement of the rotation speed performed by using the detection signal corresponding to the rotation of a predetermined angle in one cycle can be performed at a time interval shorter than the cycle of the detection signal.
Further, when the existing test system includes a member in which a plurality of convex portions are arranged in the circumferential direction that rotates with the rotation axis of the test body 100, a detection signal required for a magnetic sensor is transmitted to the member. By changing the structure only by arranging it so that it can be obtained, the member can be diverted as the rotating disk 5, and the measurement of the rotation speed performed by using the detection signal corresponding to one cycle corresponding to the rotation of a predetermined angle can be detected. It can be done at shorter time intervals than the signal period.

Further, even when the existing test system does not include a member in which a plurality of convex portions are arranged in the circumferential direction to rotate with the rotation axis of the test body 100, the rotary disk 5 rotates with the rotation axis of the test body 100. This can be realized by simply changing the structure by simply arranging the magnetic sensor 7 with respect to the member so that a required detection signal can be obtained.

Here, the test system shown in the above embodiments may be applied in various forms depending on the test body 100 and the purpose of the test to be performed.
For example, when the connected transmission and drive shaft are tested as the test body 100, the dynamometer 1 is connected to the left and right drive shafts 101 via the torque sensor 2, respectively, as shown in FIG. At the same time, a drive motor 9 simulating an electric motor of an automobile is connected to a transmission 102 via a torque sensor 2.

Then, the rotary disk 5 and the four magnetic sensors 7 described above are provided in at least one torque sensor 2, and the rotation speed thereof is measured.
Further, in the above embodiment, a disk having slits arranged in the circumferential direction is used as the rotating disk 5, and instead of the magnetic sensor 7, a light source that emits light rays toward the disk and light passing through the slits are detected. An optical sensor composed of a light receiving element may be used. However, in this case, the four optical sensors are arranged so that the four detection signals A *, B *, A ~ *, and B ~ * whose phases are sequentially shifted by 90 degrees can be obtained.

1 ... Dynamometer, 2 ... Torque sensor, 3 ... Shaft, 4 ... Intermediate bearing, 5 ... Rotating disk, 6 ... Frame, 7 ... Magnetic sensor, 8 ... Measurement control system, 9 ... Drive motor, 81 ... Rotation speed detector , 82 ... Operation control unit, 83 ... Measurement processing unit, 100 ... Test piece, 101 ... Drive shaft, 102 ... Transmission, 811 ... Low speed range rotation speed calculation unit, 812 ... Rotation speed calculation unit, 813 ... Switching processing unit, 8111 ... signal adjusting unit, 8112 ... first signal generation unit, 8113 ... second signal generation unit, 8114 ... first angle signal calculation unit, 8115 ... second angle signal calculation unit, 8116 ... differential signal calculation unit, 8117 ... rotation speed Conversion part.

Claims (9)

A test system for testing a test piece having a rotating shaft.
A turntable that rotates with the axis of rotation,
As φ = 2π / n (where n is an integer), a signal A, which is a periodic signal in which one cycle appears each time the turntable rotates by an angle φ, and a signal, which is a periodic signal whose phase is 90 degrees different from that of the signal A. A signal generation means that generates B and
From signal A and signal B using the atan2 function, with the rotation of the turntable in a predetermined rotation direction, the period from -π to + π is the same as the period of signal A and signal B. An angle signal θ1 and an angle signal θ2 that repeat an increase proportional to the increase in the rotation angle in the predetermined rotation direction of the turntable with a positive proportional coefficient in different phases are generated, and ω1 = dθ1 (t) / dt, Differentiated signal generation means to calculate ω2 = dθ2 (t) / dt,
In the period including the period in which the angular signal θ1 changes from + π to -π and the period in which the angular signal θ2 changes from + π to -π when the rotary disk is rotating in the predetermined rotation direction. Ω is calculated by letting ω1 be ω in a certain first period and ω2 in the second period excluding the first period, and the angular velocity ωd1 (rad / s) of the turntable is calculated. , Ωd1 = ω / n A test system characterized by having an angular velocity calculating means. The test system according to claim 1.
The signal A is 90 degrees ahead of the signal B in phase.
The differential signal generation means uses any one of atan2 (B, A), atan2 (-B, -A), atan2 (-A, B), and atan2 (A, -B) as an angle signal θ1. , A test system characterized in that the angle signal θ1 and the angle signal θ2 are generated by using any one of the other as the angle signal θ2. A test system for testing a test piece having a rotating shaft.
A turntable that rotates with the axis of rotation,
As φ = 2π / n (where n is an integer), a signal A, which is a periodic signal in which one cycle appears each time the turntable rotates by an angle φ, and a signal, which is a periodic signal whose phase is 90 degrees different from that of the signal A. A signal generation means that generates B and
From + π to -π from signal A and signal B using the atan2 function, with a period of the same time length as the period of signal A and signal B as the rotating disk rotates in a predetermined rotation direction. Ω1 = -d θ1 (t) / dt is generated by generating an angle signal θ1 and an angle signal θ2 that repeats a decrease proportional to the increase in the rotation angle in the predetermined rotation direction of the turntable with a negative proportional coefficient in different phases. , Ω2 = -d θ2 (t) / dt and the differential signal generation means,
In the period including the period in which the angular signal θ1 changes from -π to + π and the period in which the angular signal θ2 changes from -π to + π when the rotary disk is rotating in the predetermined rotation direction. Ω is calculated by letting ω1 be ω in a certain first period and ω2 in the second period excluding the first period, and the angular velocity ωd1 (rad / s) of the turntable is calculated. , Ωd1 = ω / n A test system characterized by having an angular velocity calculating means. The test system according to claim 3.
The signal A is 90 degrees ahead of the signal B in phase.
The differential signal generation means uses any one of atan2 (-B, A), atan2 (B, -A), atan2 (A, B), and atan2 (-A, -B) as an angle signal θ1. , A test system characterized in that the angle signal θ1 and the angle signal θ2 are generated by using any one of the other as the angle signal θ2. The test system according to claim 1, 2, 3 or 4.
On the turntable, the n convex portions are arranged in the circumferential direction.
The signal generation means has different phases with respect to the convex portion so as to detect the two detection signals used as the signal A and the signal B by the magnetic change accompanying the movement of the convex portion due to the rotation of the turntable. A test system characterized by having two magnetic sensors arranged in a row. The test system according to claim 1, 2, 3 or 4.
On the turntable, the n convex portions are arranged in the circumferential direction.
The signal generation means is
Four detection signals A *, B *, whose phases are sequentially shifted by 90 degrees, in which one cycle appears each time the rotary disk rotates by an angle φ due to the magnetic change accompanying the movement of the convex portion due to the rotation of the rotary disk. Four magnetic sensors arranged in different phases with respect to the convex portion so as to detect A ~ * and B ~ * respectively, and
A test system characterized by having a signal calculating means for calculating the signal A and the signal B from A = A * -A ~ * and B = B * -B ~ *. The test system according to claim 5 or 6.
A second angular velocity calculating means for calculating the angular velocity ωd2 (rad / s) of the rotating disk by dividing the number of cycles per unit time of the detection signal detected by the magnetic sensor by n.
It has a switching means for outputting one of the angular velocity ωd1 (rad / s) calculated by the angular velocity calculating means and the angular velocity ωd2 (rad / s) calculated by the second angular velocity calculating means as the angular velocity ωd of the rotating disk.
When the angular velocity ωd becomes larger than the first threshold value when the angular velocity ωd1 (rad / s) calculated by the angular velocity calculating means is output as the angular velocity ωd of the turntable. , The angular velocity ωd of the rotating disk to be output is switched to the angular velocity ωd2 (rad / s) calculated by the second angular velocity calculating means, and the angular velocity ωd2 (rad / s) calculated by the second angular velocity calculating means of the rotating disk. When the angular velocity ωd is output as the angular velocity ωd and the angular velocity ωd becomes equal to or less than the second threshold value which is the threshold value equal to or less than the first threshold value, the angular velocity ωd of the rotating disk to be output is calculated. A test system characterized by switching to the angular velocity ωd1 (rad / s) calculated by the angular velocity calculating means. The test system according to claim 5, 6 or 7.
It has a dynamometer and a torque sensor that connects the shaft of the dynamometer and the rotation shaft of the test piece.
The rotary disk is a test system included in the torque sensor, characterized in that a plurality of teeth are formed as the convex portions on the outer periphery thereof. The test system according to claim 1, 2, 3, 4, 5, 6, 7 or 8.
The test body is a test system characterized by being an automobile, a power train of an automobile, or a component of a power train of an automobile.

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