JP2016080378A - Rotational speed information detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotational speed information detection device capable of obtaining a rotational speed variation component with a high S/N ratio, and accurately obtaining information on minute rotational variation.SOLUTION: A rotational speed information detection device comprises a rotation sensor 2 and a signal processing unit 3. The signal processing unit 3 includes: a sensor error correction means 4 that corrects a rotation signal output from the rotation sensor 2 with a pattern for error correction; and a rotation variation pattern extraction processing means 5 that calculates a rotation speed variation pattern synchronized with rotation from the corrected rotation signal. The rotation variation pattern extraction processing means 5 consists of an extraction determination part 5a and a pattern calculation part 5b. The extraction determination part 5a evaluates an input rotation signal for each predetermined number of rotations, such as for one rotation, to determine whether or not to extract the signal. The pattern calculation part 5b, using the rotation signal determined to be extracted, calculates the rotation speed variation pattern according to predetermined rules.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a rotation speed information detection apparatus that extracts a rotation speed from a signal of a rotation sensor and monitors a state of a rotating body, for example, a rotation signal processing technique of a wheel speed sensor provided in a wheel bearing.

Conventionally, a speed detection device having a function of correcting a duty ratio and a phase shift in an output signal of a pulse encoder using a correction amount stored in advance has been proposed (for example, Patent Document 2).
Further, a method for estimating a slip ratio or the like from a tire rotation sensor signal is presented, and a method for averaging and detecting a rotation synchronization component from a tire rotation signal over several revolutions is also presented (for example, Patent Document 4). ).

  In addition to this, as shown in FIGS. 10 to 12, in the rotation detection device that outputs a pulse obtained by multiplying the reference signal of the encoder 2a, a correction for correcting an error included in the multiplied output by using identification information of the multiplied pulse. The thing provided with the means is shown (for example, patent document 3). FIG. 12 shows the fluctuation of the pulse period before and after the correction.

JP 08-128855 A JP 2002-311040 A JP 2008-249574 A JP 2006-126164 A

  Patent Documents 1 to 3 propose a method for correcting an error included in the pulse output of the encoder. Japanese Patent Application No. 2013-166409 proposes a method of correcting a magnetizing pitch error and an error due to attachment of an encoder.

  Further, when data is extracted in an arbitrary speed range from the rotation signal output from the rotation sensor and a rotation speed fluctuation pattern per one rotation of the shaft is created, information on the state of the rotating body can be extracted from the information. For example, vehicle information and road surface information can be detected.

  However, since the vehicle information, road surface information, and the like are detected from minute changes in the rotation sensor, if affected by unnecessary disturbances or changes in driving conditions, the quality of the extracted data is reduced and errors are large. turn into.

  An object of the present invention is to provide a rotation speed information detection device that can acquire a rotation speed fluctuation component having a high S / N ratio and can acquire information on minute rotation fluctuation with high accuracy.

The rotational speed information detecting device according to the present invention includes an encoder 2a that rotates together with a rotation detection object, a rotation sensor 2 having a sensor 2b that reads the encoder 2a, and a signal processing unit that processes a rotation signal output from the rotation sensor 2. 3.
The signal processing unit 3
Sensor error correction means 4 for correcting at least one of pitch error, attachment error, and sensor error of the encoder 2a with an error correction pattern for the rotation signal output from the rotation sensor 2;
And a rotation fluctuation pattern extraction processing means 5 for calculating a rotation speed fluctuation pattern synchronized with the rotation from the corrected rotation signal.
The rotation variation pattern extraction processing means 5 is determined to be extracted by the extraction determination unit 5a for determining whether or not to extract the input rotation signal for every predetermined number of rotations, and to extract by the extraction determination unit 5a. And a pattern calculation unit 5b for calculating the rotation speed variation pattern according to a rule determined using the rotation signal.

According to this configuration, the rotation variation pattern extraction processing means 5 determines whether or not the input rotation signal of the rotation sensor 2 is evaluated and extracted every predetermined number of rotations by the extraction determination unit 5a. The predetermined number of rotations may be one rotation or a plurality of predetermined rotations. Using the rotation signal determined to be extracted by the extraction determination unit, the rotation speed variation pattern is calculated by processing according to some predetermined rule.
In this way, the input rotation signal of the rotation sensor 2 is extracted only when a satisfactory evaluation is obtained for each predetermined number of rotations, and a rotation speed fluctuation pattern is calculated from the extracted rotation sensor 2. Therefore, a rotation speed fluctuation pattern that is free from the influence of such disturbance can be calculated by appropriately setting an evaluation standard so that it is not extracted when there is an unnecessary disturbance or change in operating conditions. Since this rotation speed fluctuation pattern is calculated by the pattern calculation section 5b according to a predetermined rule, it becomes a rotation speed fluctuation pattern per rotation of the rotation detection object.
Further, since the rotation signal output from the rotation sensor 2 corrects the pitch error, attachment error, sensor error, and the like of the encoder 2a by the error correction pattern by the sensor error correction means 4, a more accurate rotation speed. A variation pattern can be calculated. The sensor error is an error such as nonlinearity of the sensor 2a.
For these reasons, a rotational speed fluctuation component having a high S / N ratio can be acquired as the rotational speed fluctuation pattern, and minute rotational fluctuation information can be obtained with high accuracy.

In the present invention, the pattern calculation unit 5b of the rotation variation pattern extraction processing means 5 performs a process of averaging or integrating in synchronization with rotation as the predetermined rule to calculate the rotation speed variation pattern. It is also good. Here, “perform averaging or integration” includes processing for averaging the integrated values.
By applying an averaging process or an integration process to the extraction process, the influence of random rotation fluctuations that are not effectively synchronized with the rotation of a non-rotation detector such as a tire is eliminated. For example, the influence of rotationally asynchronous disturbance due to road surface unevenness is eliminated.

  In the present invention, the rotation sensor 2 may be a magnetic encoder type rotation sensor 2 having a multiplication function for multiplying a basic signal. By providing this multiplication function, it is possible to output a high-resolution output pulse, and it is possible to extract a higher frequency component, thereby improving the accuracy of information regarding the state of the rotating body. The magnetic encoder type rotation sensor has an advantage that it is more resistant to dirt and the like than the optical rotation sensor, but the resolution is low. However, by providing a multiplication function, the rotation sensor has excellent resolution. Therefore, it is preferable for a rotation sensor in a wheel bearing or the like in an environment that is easily contaminated.

In the present invention, the extraction discriminating unit 5a of the rotation fluctuation pattern extraction processing means 5 determines whether or not to extract the rotation signal, and determines the standard deviation σ of the rotation signal for each predetermined number of rotations to be determined. Alternatively, the variance σ ² may be compared with a set threshold value.
As a result, a rotation signal that satisfies a certain standard can be selected appropriately.

In this invention, the extraction discriminating unit of the rotation fluctuation pattern extraction processing means 5 determines whether or not to extract the rotation signal, and the standard deviation σ or variance σ ^{2 for} each predetermined number of rotations to be determined. It may be determined using a value obtained by performing a predetermined standardization.
This also makes it possible to appropriately select a rotation signal that satisfies a certain standard.

  In this invention, the number of rotations evaluated for each predetermined number of rotations may be one rotation. Since the rotational speed fluctuation pattern is usually a pattern for one rotation, a necessary and sufficient evaluation can be performed by evaluating each rotation.

  In the present invention, the rotation detection body may be a rotating wheel of a wheel bearing. When applied to a wheel bearing, minute rotational fluctuations generated by driving force input from a road surface, a tire, a bearing, and a drive shaft can be acquired with high accuracy. In particular, by selecting a rotation signal to be extracted for each small number of rotations, there is no influence of sudden external forces on the tire such as road surface irregularities and manholes, so the above minute rotation fluctuations are highly accurate. Can be output as information

  The rotational speed information detection device of the present invention includes an encoder that rotates together with the rotation detection object, a rotation sensor that includes a sensor that reads the encoder, and a signal processing unit that processes a rotation signal output from the rotation sensor. The signal processing unit includes sensor error correction means for correcting at least one of the encoder pitch error, attachment error, and sensor error with an error correction pattern for the rotation signal output from the rotation sensor. Rotation fluctuation pattern extraction processing means for calculating a rotation speed fluctuation pattern synchronized with the rotation from the rotation signal. The rotation fluctuation pattern extraction processing means evaluates the input rotation signal for each predetermined number of rotations. The extraction discriminating unit for discriminating whether or not to extract the data before the extraction discriminating unit And a pattern calculation unit that calculates the rotation speed fluctuation pattern by averaging or integrating the rotation signal in synchronization with the rotation, so that a rotation speed fluctuation component having a high S / N ratio can be acquired and a minute rotation fluctuation can be obtained. Can be acquired with high accuracy.

It is a block diagram which shows the conceptual structure of the rotational speed information detection apparatus which concerns on one Embodiment of this invention. It is explanatory drawing shown about extraction by the evaluation of the rotation signal by the rotation speed information detection apparatus. It is a graph which shows an example of the rotational speed fluctuation pattern computed with the rotational speed information detection apparatus. It is a fracture | rupture front view of an example of the wheel bearing with a rotation detection apparatus which applies the error correction structure of the wheel speed sensor. It is the side view of an example which looked at the bearing for the wheels from the inboard side. It is a fracture | rupture front view which shows the other example of the wheel bearing with a rotation detector which applies the error correction structure of the wheel speed sensor. It is the side view of an example which looked at the bearing for the wheels from the inboard side. It is a fracture | rupture front view which shows the further another example of the wheel bearing with a rotation detection apparatus to which the error correction structure of the wheel speed sensor is applied. It is the side view of an example which looked at the bearing for the wheels from the inboard side. It is the fragmentary sectional view and perspective view which show an example of the rotation sensor to which the same wheel speed rotation fluctuation pattern extracting device is applied. It is the fragmentary sectional view and perspective view which show the other example of the rotation sensor to which the same wheel speed rotation fluctuation pattern extracting device is applied. It is a graph which shows the example of the conventional correction | amendment.

  An embodiment of the present invention will be described with reference to FIG. 1, FIG. 2, FIG. 10, and FIG. FIG. 1 shows an example in which this rotational speed information detection device is applied to extraction of rotational speed information from a rotation sensor mounted on a wheel bearing. A rotation sensor 2 for detecting the rotation speed of the wheel 1 and a signal processing unit 3 for processing a rotation signal output from the rotation sensor 2 are provided.

  The rotation sensor 2 is a wheel speed sensor in the example of the figure, and is installed in a wheel bearing. In addition, you may install in a drive shaft etc. For example, as shown in FIG. 10 or FIG. 11, the rotation sensor 2 includes a magnetic encoder 2a and a magnetic sensor 2b. The magnetic encoder 2a has N and S magnetic poles 2aa alternately. As will be described later with reference to FIGS. 4 to 9, the magnetic encoder 2 a is attached to a rotating wheel of a wheel bearing that is a detected body. Instead of the magnetic encoder 2a, a detection gear (not shown) may be used. From the magnetic sensor 2b, a voltage signal in the form of a sine wave or a cosine wave is output as a rotation signal that is a rotation speed signal detected by the rotation sensor 2 by the rotation of the magnetic encoder 2a. It is desirable that the rotation sensor 2 has a multiplication function and can output a high-resolution output pulse obtained by multiplying the basic signal. By providing this multiplication function, a higher frequency component can be extracted, and the accuracy of information regarding the state of the rotating body is improved. A specific example of the rotation sensor 2 will be described later.

  The signal processing unit 3 includes an electronic circuit such as a microcomputer, and may be an independent ECU (electronic control unit) or the like, or may be provided as a part of an ECU that controls the entire vehicle. The signal processing unit 3 is provided with sensor error correction means 4 for correcting an error included in the rotation signal output from the rotation sensor 2 and rotation variation pattern extraction processing means 5. The rotation fluctuation pattern extraction processing means 5 extracts a rotation speed fluctuation pattern synchronized with the rotation from the rotation signal detected by the rotation sensor 2 and corrected by the sensor error correction means 4.

  The sensor error correction unit 4 is a unit that corrects at least one of the pitch error, the attachment error, and the sensor error of the encoder 2 a with the error correction pattern for the rotation signal output from the rotation sensor 2. A detection target such as the magnetic encoder 2a used for the wheel speed sensor includes a pitch error inherent to the sensor due to manufacturing variations. Such an error is corrected by the error correction pattern. The error correction pattern is obtained by using, for example, a rotation signal measured in advance, a rotation speed created by the rotation fluctuation pattern extraction processing means 5 or a device (not shown) having the same function as the rotation fluctuation pattern extraction processing means 5. With a variation pattern. Thereby, all of the pitch error, the mounting error, and the sensor error are corrected.

In this embodiment, the sensor error correction unit 4 includes a rotation speed signal determination unit 6, an error correction memory 8, and an error correction processing unit 7.
The rotation speed signal determination unit 6 receives the rotation sensor signal output from the rotation sensor 2 and determines the rotation speed of the running wheel. The rotational speed signal discriminating unit 6 outputs the result of discriminating the rotational speed as a rotational speed value, or outputs it as information about which rotational speed region appropriately divided into a plurality of stages. Anyway.

The error correction memory 8 stores an error correction pattern for correcting an error of the rotation signal of the rotation sensor 2 (which may be an error of the encoder 2a). The error correction pattern is, for example, a rotational speed variation pattern synchronized with the rotation of the wheel 1 for one rotation.
The error correction processing unit 7 uses the error correction pattern stored in the error correction memory 8 to correct the error of the rotation signal according to the rotation speed determined by the rotation speed determination unit 6.

  More specifically, the error correction memory 8 is set with a plurality of types of error correction patterns that differ depending on the rotation speed. For example, an error correction pattern is set for each speed category in which the rotation speed range is appropriately divided into several categories or several tens categories. In that case, the error correction processing unit 7 selects an optimal error correction pattern from the plurality of types of error correction patterns, specifically, an error correction pattern corresponding to the rotation speed determined by the rotation speed determination unit 6, Correction is performed with the selected error correction pattern. When the rotation speed determination unit 6 determines a rotation speed category, an error correction pattern corresponding to the determined category is selected from the error correction memory 8. When the rotational speed discriminating unit 6 outputs a speed value, the error correction processing unit 7 discriminates which speed category the speed value belongs to, and selects a corresponding error correction pattern.

  The rotation fluctuation pattern extraction processing means 5 is a means for calculating a rotation speed fluctuation pattern synchronized with the rotation of the wheel 1 using the rotation signal corrected by the sensor error correction means 4. The rotation fluctuation pattern extraction processing means 5 uses a low-pass filter (LPF) or a low-pass filter (LPF) for the input rotation signal depending on the information to be detected, for example, for the purpose of abnormality determination using the output rotation speed fluctuation pattern. Filter processing may be performed by a high-pass filter (HPF), or the number of extracted data may be set and the number of data within the set number may be output.

  The rotation variation pattern extraction processing means 5 includes an extraction determination unit 5a that determines whether or not the input rotation signal is evaluated and extracted every predetermined number of rotations (for example, one rotation), and the extraction determination unit 5a. A pattern calculation unit 5b that calculates the rotation speed fluctuation pattern synchronized with the rotation using the rotation signal determined to be extracted. Note that the processing for limiting the LPF and HPF and the number of extracted data within a set number may be performed by the pattern calculation unit 5b, and the rotation variation pattern extraction processing unit 5 is preceded by the extraction determination unit 5a. You may make it do.

  The pattern calculation unit 5b calculates the rotation speed fluctuation pattern according to a predetermined rule. Since the rotational speed variation pattern is affected by the rotational speed, it is desirable to create it for each arbitrary speed region. In addition, in order to eliminate the influence of rotation asynchronous disturbance due to road surface irregularities, etc., a rotation signal for a period over a certain number of rotations is collected and processed according to the predetermined rule to obtain a specific rotation speed fluctuation pattern. Extract. The “rule” may be any appropriate rule. An example of the extracted rotational speed fluctuation pattern is shown in FIG.

The pattern calculation unit 5b performs, for example, averaging or integration processing as the determined rule, and extracts the rotation speed fluctuation pattern. As a specific example, a value obtained by accumulating data for each pulse in rotation synchronization is divided by an average value of all pulses. By applying averaging processing and integration processing to the extraction processing, the influence of random rotation fluctuations that are not effectively synchronized with the rotation of the tire is eliminated.
As an example of the averaging process, the rotation signal output from the rotation sensor 2 is calculated by averaging the passing speed or the time required to pass through each magnetic pole of the encoder 2a for a plurality of rotations with a period of one rotation. To do. Not only taking a simple average but also taking a weighted average that puts more weight on the previous value than the past value, the latest rotation characteristics can always be obtained, and changes over time such as tire characteristics can be followed. .

  By collecting rotation signals over a period of a certain number of rotations and extracting a specific rotation speed fluctuation pattern by averaging or integration processing, the effects of asynchronous rotation due to road surface irregularities can be eliminated. The effect of random rotation fluctuations that are not synchronized with the rotation of the rotation is effectively eliminated. Components caused by the tread pattern of the tire 1a are included in the rotational speed fluctuation pattern, and are extracted as the rotational speed fluctuation pattern.

The extraction discriminating unit 5a determines the standard deviation of the rotation signal data, which is the speed data during the rotation of the input rotation signal for each predetermined number of rotations, that is, for each determined number of rotations (interval). (Σ), variance (σ ² ), or their normalized values (σ _v / v, σ _v ² / v, v: average speed), etc. are calculated, and the corresponding data in the meantime is calculated by the pattern calculation unit 5b. Judge whether to use for (for example, integration). As a result, only quality data that satisfies a certain standard is extracted. The “predetermined number of rotations” may be, for example, one rotation or a plurality of rotations such as several times. Since the rotational speed fluctuation pattern is usually a pattern for one rotation, a necessary and sufficient evaluation can be performed by evaluating each rotation.

For example, the extraction determination unit 5a compares the standard deviation σ or variance σ ² of the rotation signal for each number of rotations to be determined with a set threshold as a determination as to whether or not to extract the rotation signal. You may make it judge by doing.
Further, the determination as to whether or not to extract the rotation signal may be performed using a value standardized with an average speed v for the standard deviation σ or variance σ ^{2 for} each rotation speed to be determined.

The extraction discriminating unit 5a performs the following processing when regrouped and specifically described.
・ Limit the speed range to be extracted. This makes it possible to detect desired characteristics.
The pulse length variance σ ² or the converted velocity variance is calculated for each predetermined number of revolutions (for example, one revolution), and when the variance exceeds a specified value, data corresponding to the number of revolutions is excluded. Thereby, the detection accuracy of vehicle and road surface information improves.
For example, if the dispersion of the pulse length per rotation or the dispersion of the converted speed is calculated and the dispersion in each case is σ ² , then σ ² > X (X is a threshold value, that is, a specified value) Excluded data is excluded (FIG. 2). This figure shows an example in which the predetermined rotational speed 1 is one rotation and the pulse length variance σ ² is determined.

That is, the extraction determination unit 5a performs the following processes (1) to (3).
(1) Extract data consisting of rotation signals in an arbitrary speed range.
(2) Calculate the data dispersion (standard deviation (σ) and variance (σ ² )).
(3) The variation is judged by the threshold value X, and when an outlier is included, a rotation signal that is data corresponding to the number of rotations is excluded.
(4) The rotation signal extracted by the extraction determination unit 5a is determined in this way, and the extracted rotation signal data is used by the pattern calculation unit 5b to create integrated data for each pulse as described above, for example.

According to this rotational speed information detection device, the following effects can be obtained by obtaining the rotational speed fluctuation pattern as described above.
By correcting the vehicle speed variation of the rotation signal that is the data to be extracted, a rotation speed fluctuation component having a high S / N can be acquired.
This makes it possible to acquire minute rotational fluctuations generated by driving forces input from road surfaces, tires, bearings, drive shafts, and the like with higher accuracy.
-In particular, by selecting the rotation signal data to be extracted for each small number of rotations that is the predetermined number of rotations, it is not affected by sudden external forces on the tire such as uneven roads and manholes, The minute rotational fluctuations can be output as highly accurate information.

  FIG. 10 shows a specific example of the rotation sensor 2. The rotation sensor 2 is a radial type magnetic type, and includes an annular magnetic encoder 2a that is a target, and a magnetic sensor 2b that faces the outer peripheral surface of the magnetic encoder 2a and detects the magnetism of the magnetic encoder 2a. . The magnetic encoder 2a has N and S magnetic poles 2aa alternately, and outputs a sine wave rotation signal from the magnetic sensor 2b. The sinusoidal rotation signal is shaped into a rectangle by the signal processing unit 2c and output as a rectangular wave pulse signal. The signal processing unit 2c may include a multiplication circuit 2ca, and in that case, outputs a multiplied high-resolution rotation signal.

  The magnetic encoder 2a may include a magnetic pole 2ab for detecting the Z phase (zero phase) in one place on the circumference, aligned in the axial direction with the magnetic pole 2aa. In this case, the magnetic sensor 2b In addition to the sensor unit 2ba for detecting the N and S alternating magnetic poles 2aa, a sensor unit 2bb for detecting the magnetic pole 2ab for detecting the Z phase is provided. This sensor unit 2bb outputs a Z-phase (zero-phase) signal once in one rotation.

  FIG. 11 shows another example of the rotation sensor 2. The rotation sensor 2 is an axial magnetic type, and an annular magnetic encoder 2a and a magnetic sensor 2b face each other in the axial direction. The magnetic encoder 2a is attached to a flange portion of a sensor attachment ring 2d having an L-shaped cross section. Other configurations are the same as those of the radial type rotation sensor 2 shown in FIG. Although not shown in the example of FIG. 11, this radial type rotation sensor 2 may also be provided with a zero-phase magnetic pole, a sensor unit, and a multiplication circuit, as described above.

10 and 11 both show the rotation sensor 2 having the magnetic encoder 2a. However, the rotation sensor 2 is a pulsar ring (not shown) whose target is made of a gear-type magnetic material, a so-called detection gear. May be. In that case, the magnetic sensor detects the teeth of the pulsar ring and outputs a rotation signal.
The magnetic rotation sensor 2 using the magnetic encoder 2a and the gear-type pulsar ring is resistant to inferior environments such as temperature changes and dirt. In the case of the magnetic type, it is difficult to provide the magnetic poles more finely than in the optical type. However, if the multiplication circuit 2ca is provided, a rotation signal having a resolution necessary for detecting the rotation speed fluctuation pattern can be obtained.

  4 to 9 show examples of wheel bearings provided with the rotation sensor 2. The wheel bearing 30 shown in FIGS. 4 and 5 is a third generation type inner ring rotation type and for driving wheel support, and shows an example in which the rotation sensor 2 is provided in the center of the double row. The wheel bearing 30 includes an outer member 31 in which a double row rolling surface 33 is formed on the inner periphery, and an inner member 32 that is a rotating wheel in which a rolling surface 34 that faces each of the rolling surfaces 33 is formed. And a double-row rolling element 35 interposed between the rolling surfaces 33 and 34 of the outer member 31 and the inner member 32, and supports the wheel rotatably with respect to the vehicle body. The wheel bearing 30 is a double-row outward angular ball bearing type, and the rolling elements 35 are formed of balls and are held by a cage 36 for each row. The inner member 32 includes a hub wheel 32a and an inner ring 32b fitted to the outer periphery of the inboard side end of the hub wheel 32a. The rolling surface 34 is provided on the outer periphery of each wheel 32a, 32b. . Both ends of the bearing space between the outer member 31 and the inner member 32 are sealed by seals 37 and 38, respectively.

  In the wheel bearing 30, the encoder 2 a of the rotation sensor 2 is provided on the outer periphery between the rolling surfaces 34 of the inner member 32, and the magnetic sensor 2 b facing the encoder 2 a is provided on the outer member 31. It is installed in the provided sensor mounting hole 40 in the radial direction. The rotation sensor 2 is, for example, the radial type described above with reference to FIG.

  The wheel bearing 30 shown in FIGS. 6 and 7 is a third generation inner ring rotation type and is for driving wheel support, and shows an example in which the rotation sensor 2 is provided at the inboard side end. In this example, the rotation sensor 2 is of the axial type described above with reference to FIG. Specifically, a slinger that is press-fitted and fixed to the outer peripheral surface of the inner member 32 in the seal 38 at the inboard side end also serves as the sensor support ring 2d in the example of FIG. The magnetic sensor 2 b is resin-molded in a ring-shaped metal case 39 and fixed to the outer member 31 via the metal case 39. Other configurations are the same as those of the example shown in FIGS.

  The wheel bearing 30 shown in FIGS. 8 and 9 is a third generation inner ring rotating type and is for supporting a driven wheel, and shows an example in which the rotation sensor 2 is provided at the inboard side end. In this example, the end face opening at the inboard side end portion of the outer member 31 is covered with a cover 29, and the magnetic sensor 2 b of the rotation sensor 2 is attached to the cover 29. Other configurations and operational effects are the same as those of the example shown in FIGS.

  In addition, although the said embodiment demonstrated about the case where the rotational speed of the wheel 1 was detected, this invention is applicable to the detection of the rotational speed information in various apparatuses generally.

DESCRIPTION OF SYMBOLS 1 ... Wheel 1a ... Tire 2 ... Rotation sensor 2a ... Magnetic encoder 2b ... Magnetic sensor 2C ... Multiplication means 3 ... Signal processing unit 4 ... Sensor error correction means 5 ... Rotation fluctuation pattern extraction processing means 5a ... Extraction judgment part 5b ... Pattern calculation Unit 6 Rotational speed determination unit 6 Rotational speed determination unit 7 Error correction processing unit 8 Error correction memory

Claims (7)

A rotation sensor having an encoder that rotates together with the rotation detection body and a sensor that reads the encoder; and a signal processing unit that processes a rotation signal output from the rotation sensor;
The signal processing unit is
Sensor error correction means for correcting at least one of the encoder pitch error, attachment error, and sensor error with an error correction pattern for the rotation signal output from the rotation sensor;
Rotation fluctuation pattern extraction processing means for calculating a rotation speed fluctuation pattern synchronized with the rotation from the corrected rotation signal;
The rotation fluctuation pattern extraction processing means evaluates the input rotation signal for each predetermined number of rotations to determine whether or not to extract and the rotation determined to be extracted by the extraction determination unit. A rotation speed information detection apparatus, comprising: a pattern calculation unit that calculates the rotation speed fluctuation pattern according to a rule determined using a signal.   The rotational speed information detection apparatus according to claim 1, wherein the pattern calculation unit of the rotation variation pattern extraction processing unit performs a process of averaging or integrating in synchronization with rotation as the determined rule, A rotational speed information detecting device for calculating a speed fluctuation pattern.   3. The rotational speed information detecting device according to claim 1, wherein the rotational sensor is a magnetic encoder type rotational sensor having a multiplication function.   4. The rotational speed information detection device according to claim 1, wherein the extraction determination unit of the rotation variation pattern extraction processing unit determines whether to extract the rotation signal. A rotation speed information detection apparatus that performs the comparison by comparing a standard deviation σ or variance σ2 of a rotation signal for each predetermined rotation speed as a target with a set threshold value.   4. The rotational speed information detection device according to claim 1, wherein the extraction determination unit of the rotation variation pattern extraction processing unit determines whether to extract the rotation signal. A rotation speed information detection apparatus that uses a value obtained by performing a predetermined standardization on the standard deviation σ or variance σ2 for each predetermined rotation speed.   6. The rotational speed information detecting device according to claim 1, wherein the rotational speed evaluated for each predetermined rotational speed is one rotation.   7. The rotational speed information detecting device according to claim 1, wherein the rotation detection body is a rotating wheel of a wheel bearing.

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