JP2022024580A - Rotation state detector - Google Patents

Abstract

To provide a rotation state detector that can properly detect a torque generated in the direction of rotation of a wheel.SOLUTION: A first sensor unit detects the state of rotation of a wheel 92 by detecting a magnetic ring 35, and a second sensor unit 32 detects the state of rotation of the wheel 92 by detecting the magnetic ring 35 and is located separately from the first sensor unit. A rotation rate operation unit 451 operates the rate of rotation of the wheel 92 on the basis of a first detection signal Sg1 and a second detection signal Sg2. A torque operation unit 452 operates a torque in the direction of rotation of the wheel 92 on the basis of the first detection signal Sg1 and the second detection signal Sg2. In that way, it becomes possible to properly operate a torque in the direction of rotation of the wheel 92 from the detection signals Sg1 and Sg2.SELECTED DRAWING: Figure 1

Description

The present invention relates to a rotational state detection device.

Conventionally, a brake rotation state detection device that detects a torque when a rotation torque is generated on a wheel is known. For example, in Patent Document 1, a strain gauge as a brake rotation state detection device is provided at the caliper mounting portion of the brake caliper.

Japanese Unexamined Patent Publication No. 2004-264029

In Patent Document 1, since it is necessary to provide a strain gauge on the caliper support portion, it is easily affected by the heat generated by the braking device. Further, in order to perform stable measurement, it is necessary to install a device for performing an operation using a signal from the strain gauge near the strain gauge, which complicates the configuration. The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a rotation state detection device capable of appropriately detecting torque generated in the rotation direction of a wheel.

The rotation state detection device of the present invention includes a detected unit (35, 135), a first sensor unit (31, 131), a second sensor unit (32, 132), and a control unit (45). .. The detected portion rotates integrally with the wheel (92). The first sensor unit detects the rotational state of the wheel by detecting the detected unit. The second sensor unit detects the rotational state of the wheel by detecting the detected unit, and is provided separately from the first sensor unit.

The control unit has a torque calculation unit (452). The torque calculation unit calculates the torque in the rotation direction of the wheel based on the first detection signal which is the detection signal of the first sensor unit and the second detection signal which is the detection signal of the second sensor unit. By using the detection signals of the two sensor units provided apart from each other, the torque generated in the rotational direction of the wheel can be appropriately detected.

It is sectional drawing which shows the rotation state detection apparatus by 1st Embodiment. It is a top view explaining the arrangement of the 1st sensor part and the 2nd sensor part by 1st Embodiment. It is a block diagram which shows the arithmetic part by 1st Embodiment. It is a figure which shows the logic circuit by 1st Embodiment. It is explanatory drawing explaining the 1st detection signal and the 2nd detection signal when the braking torque is not generated in 1st Embodiment. In the first embodiment, it is explanatory drawing explaining the 1st detection signal and the 2nd detection signal when the braking torque is generated. It is a time chart explaining the 1st detection signal, the 2nd detection signal and the composite signal by 1st Embodiment. It is a flowchart explaining the parameter calculation process by 1st Embodiment. It is a figure which shows the logic circuit by 2nd Embodiment. It is a time chart explaining the 1st detection signal, the 2nd detection signal and the composite signal by 2nd Embodiment. It is a figure which shows the logic circuit by 3rd Embodiment. It is a time chart explaining the 1st detection signal, the 2nd detection signal and the composite signal by 3rd Embodiment. It is a flowchart explaining the parameter calculation process by 3rd Embodiment. It is a flowchart explaining the parameter calculation process by 4th Embodiment. It is a block diagram which shows the arithmetic part by 5th Embodiment. It is a flowchart explaining the parameter calculation process by 5th Embodiment. It is sectional drawing which shows the rotation state detection apparatus by 6th Embodiment. It is a top view explaining the arrangement of the 1st sensor part and the 2nd sensor part by 6th Embodiment.

The rotation state detection device according to the present invention will be described with reference to the drawings. Hereinafter, in a plurality of embodiments, substantially the same configurations are designated by the same reference numerals and description thereof will be omitted.

(First Embodiment)
The first embodiment is shown in FIGS. 1 to 8. As shown in FIG. 1, the rotation state detection device 30 is used for detecting the braking torque by the braking device 10 of the vehicle. The braking device 10 is an electric braking device and includes a brake disc 15, a braking force generating unit 20, and an actuator (not shown) that generates power to drive the braking force generating unit 20. The brake disc 15 is provided on the axle 91 and rotates integrally with the wheels 92. A hub bearing 93 is provided on the axle 91. The hub bearing 93 has an outer ring 94, an inner ring 95, and a ball 96.

The braking force generating unit 20 has a caliper 21 and a brake pad 22. The caliper 21 holds the brake pad 22. The pair of brake pads 22 are provided on both sides of the brake disc 15 with the brake disc 15 interposed therebetween. A piston or the like (not shown) is operated by the driving force of the actuator, and the brake pad 22 sandwiches the brake disc 15 to generate a braking force. One side of the caliper 21 is supported by a caliper support portion 97 extending radially outward from the outer ring 94.

As shown in FIGS. 1 and 2, the rotation state detection device 30 includes a first sensor unit 31, a second sensor unit 32, a magnetic ring 35 as a detection unit, a calculation unit 40, and the like. The magnetic ring 35 is provided on the inner ring 95 side and rotates integrally with the axle 91.

The sensor units 31 and 32 are provided on the outer ring 94 side, and detect changes in the magnetic field due to the rotation of the magnetic ring 35. Thereby, the wheel speed, which is the rotation speed of the wheel 92, can be detected. In the figure, the first sensor unit 31 is referred to as “vehicle speed sensor 1” and the second sensor unit 32 is referred to as “vehicle speed sensor 2” as appropriate. The detection signal Sg1 of the first sensor unit 31 and the detection signal Sg2 of the second sensor unit 32 are output to the output circuit unit 41.

As shown in FIG. 2, the caliper support portion 97 is formed so as to project from two locations on the radial outer side of the outer ring 94. The number and shape of the caliper support portions 97 may be different. In the present embodiment, the caliper support portion 97 is formed to have a relatively narrow width, and is deformed by receiving a braking force. Here, the region where the deformation is relatively large due to the braking force is referred to as the deformation region Rt, and the region which is substantially not deformed by the braking force is referred to as the non-deformation region Rn. In the present embodiment, the region on the caliper 21 side defined at both ends of the caliper support portion 97 is defined as the deformation region Rt. The deformable region Rt and the non-deformable region Rn are set according to the shape of the caliper support portion 97 and the like. The same applies to the deformed region Rt and the non-deformed region Rn according to the fifth embodiment described later.

The first sensor unit 31 is provided in the non-deformable region Rn, and the second sensor unit 32 is provided in the deformable region Rt. The sensor units 31 and 32 are provided apart from each other to the extent that a change in signal output due to a change in the relative distance between the sensors due to the generation of braking torque can be detected. By separating the mounting positions of the two sensor portions 31 and 32, the rigidity of the hub bearing 93 and the caliper support portion 97 can be ensured.

As shown in FIG. 3, the calculation unit 40 includes an output circuit unit 41 and a control unit 45. The output circuit unit 41 has an output signal synthesis unit 411. The output signal synthesis unit 411 synthesizes the detection signal Sg1 from the first sensor unit 31 and the detection signal Sg2 from the second sensor unit 32 to generate the combined signal Sc_a. The detection signals Sg1 and Sg2 are sinusoidal signals, and are appropriately converted into rectangular wave signals before the combined signal Sc_a is generated. The sensor units 31, 32 and the magnetic ring 35 are configured such that the detection signals Sg1 and Sg2 form a plurality of pulses for one rotation of the wheel 92. The resolution can be improved by increasing the number of pulses during one rotation.

As shown in FIG. 4, the output signal synthesis unit 411 of the present embodiment has an OR circuit which is a logic circuit. By providing the output circuit unit 41 separately from the control unit 45 so that the combined signal Sc_a is input to the control unit 45, it is not necessary to change the configuration such as the number of ports on the control unit 45 side.

Returning to FIG. 3, the control unit 45 is mainly composed of a microcomputer and the like, and has a CPU, ROM, RAM, I / O, and a bus line connecting these configurations, which are not shown inside. .. Each process in the control unit 45 may be software processing by executing a program stored in advance in a substantive memory device such as a ROM (that is, a readable non-temporary tangible recording medium) on the CPU. It may be hardware processing by a dedicated electronic circuit.

The control unit 45 has a rotation speed calculation unit 451, a rotation torque calculation unit 452, a braking force control unit 455, and the like as functional blocks. In FIG. 3, the rotation speed calculation unit 451 and the rotation torque calculation unit 452 and the braking force control unit 455 are provided in one control unit, but at least one functional block may be configured as a separate control unit.

The rotation speed calculation unit 451 calculates the wheel speed detection value spd, which is the rotation speed of the wheel 92, based on the signal cycle of the combined signal Sc_a. The rotational torque calculation unit 452 calculates the braking torque detection value trq as the rotational torque generated on the axle 91 based on the pulse width of the combined signal Sc_a. The braking force control unit 455 controls the braking force based on the detection value of the stroke sensor that detects the depression amount of the brake pedal (not shown), the calculated braking torque detection value trq, and the like.

The detection signals Sg1 and Sg2 will be described with reference to FIGS. 5 and 6. In FIGS. 5 and 6, (a) shows the sensor units 31 and 31, (b) shows the detection signals Sg1 and Sg1, and (c) shows the detection signals Sg1 and Sg2 after conversion into a square wave.

As shown in FIG. 5, the sensor units 31 and 32 are provided so that an arbitrary phase difference is generated in the detection signals Sg1 and Sg2 in a state where the braking torque is not generated. At this time, there may be no phase difference between the detection signals Sg1 and Sg2. In the present embodiment, the first sensor unit 31 is provided in the non-deformation region Rn where deformation due to braking torque is unlikely to occur, and the second sensor unit 32 is provided in the deformation region Rt where deformation due to braking torque is likely to occur.

Therefore, as shown in FIG. 6A, when the braking torque is generated, the second sensor unit 32 is displaced according to the braking torque (see arrow A1), and the relative distance between the sensor units 31 and 32 changes. As a result, as shown in FIGS. 6 (b) and 6 (c), the phase difference between the detection signals Sg1 and Sg2 changes. In the present embodiment, the braking torque can be calculated based on the amount of change in the phase difference between the detection signals Sg1 and Sg2.

The upper part of FIG. 7 shows the detection signals Sg1, Sg2 and the combined signal Sc_a when there is no load, that is, when the braking torque is not generated, and the lower part shows the detection signals Sg1, Sg2 and the combined signal Sc_a when there is no load, that is, when the braking torque is generated. The detection signals Sg1 and Sg2 and the combined signal Sc are shown. In FIG. 7, the waveforms after the square wave conversion are shown as the detection signals Sg1 and Sg2, and the signals after the square wave conversion are simply referred to as “detection signals Sg1 and Sg2”. The same applies to FIGS. 10 and 12 according to the embodiments described later.

When there is no load, the detection signals Sg1 and Sg2 have the same edge width and pulse width, and are out of phase. Further, the combined signal Sc_a has a pulse width Pl corresponding to the phase difference between the detection signals Sg1 and Sg2. The edge width Ed of the combined signal Sc_a is equal to the edge width of the detection signals Sg1 and Sg2. Here, the edge width Ed can also be regarded as the rising period of the edge.

When a load due to braking torque is generated, the displacement of the first sensor unit 31 is sufficiently smaller than the displacement of the second sensor unit 32, and the phases of the detection signal Sg1 and the detection signal Sg2 are deviated from those when no load is applied. Therefore, when a load is generated, the pulse width Pl of the combined signal Sc_a changes. Further, the edge width Ed of the combined signal Sc_a does not change between no load and no load. Therefore, in the present embodiment, the braking torque detection value trq is calculated based on the pulse width Pl of the combined signal Sc_a, and the wheel speed detection value spd is calculated based on the edge width Ed.

The parameter calculation process of this embodiment will be described with reference to the flowchart of FIG. This process is executed every time the control unit 45 detects the rising edge of the pulse edge of the combined signal Sc_a. Further, the calculation cycle may be appropriately changed, for example, the calculation may be performed for each of a plurality of pulses or for each predetermined period. Hereinafter, the “step” of step S101 is omitted and simply referred to as the symbol “S”. The same is true for the other steps.

In S101, the control unit 45 acquires the combined signal Sc_a from the output circuit unit 41. In S102, the rotation torque calculation unit 452 calculates the pulse width change amount ΔPl of the combined signal Sc_a. The pulse width change amount ΔPl is the difference between the pulse width Pl of the acquired combined signal Sc_a and the pulse width Pl0 when no load is applied. In S103, the rotation torque calculation unit 452 calculates the braking torque detection value trq based on the pulse width change amount ΔPl.

In S104, the rotation speed calculation unit 451 calculates the edge rise period of the combined signal Sc_a. In S105, the rotation speed calculation unit 451 calculates the wheel speed detection value spd based on the edge rising cycle of the combined signal Sc_a. The processes of S102 to S105 may be sequentially changed in order or may be performed in parallel. The same applies to the parameter calculation process according to the embodiment described later.

In the conventional hydraulic brake, the pressing force acting on the piston can be calculated from the hydraulic pressure of the hydraulic pipe and the area of the bottom surface of the piston, and the braking force can be calculated. On the other hand, in the electric brake device, the braking force cannot be calculated from the hydraulic pressure. Therefore, in the present embodiment, the braking torque is detected by using the detection values of the two wheel speed sensors provided at separate mounting positions. This makes it possible to calculate the braking torque without using a hydraulic sensor. Further, for example, the braking torque can be calculated with higher resolution than the case of using a marker sensor or the like that performs one detection in one rotation.

Furthermore, in the present embodiment, the combined signal Sc_a is generated by the output circuit unit 41 provided outside the control unit 45 such as a microcomputer, the combined signal Sc_a is input to the control unit 45, and one combined signal Sc_a is input. Is used to calculate two pieces of information, the wheel speed detection value spd and the braking torque detection value trq. As a result, from the configuration in which one wheel speed sensor is provided, the braking torque detection value trq is added to the wheel speed detection value spd based on one synthetic signal Sc_a without changing the specifications on the microcomputer side such as the number of ports. Can be calculated.

As described above, the rotation state detection device 30 of the present embodiment includes a magnetic ring 35, a first sensor unit 31, a second sensor unit 32, and a control unit 45. The magnetic ring 35 rotates integrally with the wheel 92. The first sensor unit 31 detects the rotational state of the wheel 92 by detecting the magnetic ring 35. The second sensor unit 32 detects the rotational state of the wheel 92 by detecting the magnetic ring 35, and is provided separately from the first sensor unit 31. Specifically, the sensor units 31 and 32 detect changes in the magnetic field with the rotation of the wheels 92.

The control unit 45 has a torque calculation unit 452. The torque calculation unit 452 obtains torque in the rotational direction of the wheels 92 based on the first detection signal Sg1 which is the detection signal of the first sensor unit 31 and the second detection signal Sg2 which is the detection signal of the second sensor unit 32. Calculate.

In the present embodiment, the first sensor unit 31 and the second sensor unit 32 that detect the common magnetic ring 35 are provided apart from each other, so that the torque in the rotational direction of the wheel 92 is appropriately calculated from the detection signals Sg1 and S2. be able to.

The first sensor unit 31 is provided in the non-deformable region Rn, which is a region where the displacement due to the torque change in the rotation direction of the wheel 92 is relatively small, and the second sensor unit 32 is the displacement due to the torque change in the rotation direction of the wheel 92. Is provided in the deformation region Rt, which is a relatively large region. In the present embodiment, one of the two sensor units 31 and 32 is provided in the deformed region Rt and the other is provided in the non-deformed region Rn, and the detection signal Sg2 of the second sensor unit 32 provided in the deformed region Rt is in the rotation direction. It changes according to the torque change. By detecting the change in the detection signal Sg2 due to the torque in the rotation direction with reference to the detection signal Sg1 of the first sensor unit 31 provided in the non-deformation region Rn, the torque in the rotation direction can be appropriately calculated.

The first sensor unit 31 and the second sensor unit 32 are wheel speed sensors. The control unit 45 rotates the wheels 92 based on at least one of the first detection signal Sg1 and the second detection signal Sg2, or the signal cycle of the signal generated by using the first detection signal Sg1 and the second detection signal Sg2. It has a speed calculation unit 451 for calculating the speed. In the present embodiment, the wheel speed is calculated using the combined signal Sc_a, which is a signal generated by using the first detection signal Sg1 and the second detection signal Sg2. The torque calculation unit 452 calculates the torque in the rotation direction of the wheel 92 based on the phase difference between the first detection signal Sg1 and the second detection signal Sg2.

That is, in the present embodiment, the rotation speed of the wheel 92 and the torque in the rotation direction of the wheel 92 are calculated based on the detection values of the two wheel speed sensors. Thereby, it is possible to calculate the rotation speed and the torque in the rotation direction of the wheel 92 with a relatively simple configuration.

Further, even if the second detection signal Sg2 changes due to the torque in the rotation direction of the wheel 92, the edge width Ed of the combined signal Sc_a with respect to the rotation speed does not change. Therefore, the rotation speed should be appropriately calculated based on the edge width Ed. Can be done. Thereby, two parameters of the torque in the rotation direction of the wheel 92 and the rotation speed can be appropriately calculated based on one combined signal Sc_a. In the embodiment, the edge width Ed corresponds to the "signal period".

The rotation state detection device 30 further includes an output signal synthesis unit 411 that generates a composite signal Sc_a that combines the first detection signal Sg1 and the second detection signal Sg2. The control unit 45 acquires the combined signal Sc_a and calculates the torque in the rotation direction of the wheel 92 and the rotation speed of the wheel 92 based on the combined signal Sc_a. Since the control unit 45 uses the combined signal Sc_a, if the internal calculation of the control unit 45 is changed, the rotation speed and the rotation direction of the wheel 92 can be changed without changing the hardware configuration such as the port from the conventional wheel speed sensor. The torque can be calculated.

The output signal synthesis unit 411 has a logic circuit. The logic circuit of this embodiment is an OR circuit. Thereby, the detection signals Sg1 and Sg2 can be appropriately synthesized. Further, by using the OR circuit, even if one of the detection signals Sg1 and Sg2 becomes undetectable, the detection of the wheel speed detection value spd can be continued by using the normal signal. be.

The combined signal Sc_a is a square wave signal, and the torque calculation unit 452 calculates the torque in the rotation direction of the wheel 92 based on the pulse width Pl of the combined signal Sc_a. In the present embodiment, since the first sensor unit 31 is provided in the non-deformable region Rn and the second sensor unit 32 is provided in the deformable region Rt, the second sensor unit 32 is moved by the braking torque to obtain the first sensor unit 32. The relative distance between the sensor unit 31 and the second sensor unit 32 changes. When the phase of the second detection signal Sg2 shifts due to a change in the relative distance, the pulse width Pl of the combined signal Sc_a changes. Therefore, it is possible to appropriately detect the torque in the rotation direction based on the pulse width Pl of the combined signal Sc_a. can.

Since the pulse width of the combined signal Sc_a changes according to the phase difference between the detected signals Sg1 and Sg2, performing the torque calculation based on the pulse width of the combined signal Sc_a is "the first detection signal and the second detection". It is considered to be included in the concept of "calculating the torque in the rotation direction of the wheel based on the phase difference with the signal".

In the rotation state detection device 30, the torque calculation unit 452 calculates the braking torque as the torque in the rotation direction of the wheel 92. As a result, the braking torque can be appropriately calculated based on the detection value of the wheel speed sensor without using the hydraulic pressure sensor, and therefore, it can be suitably applied to the electric brake device.

(Second Embodiment)
The second embodiment is shown in FIGS. 9 and 10. As shown in FIG. 9, the output signal synthesis unit 412 of the present embodiment has an AND circuit which is a logic circuit. FIG. 10 is a diagram corresponding to FIG. 7, and the detection signals Sg1 and Sg2 are the same as those in the first embodiment. In the combined signal Sc_b, when a load due to the braking torque is generated, the pulse width Pl changes and the edge width Ed does not change from the case of no load. Therefore, although the waveforms are different, the braking torque detection value trq can be calculated based on the pulse width Pl using one synthetic signal Sc_b as in the first embodiment, and the wheel speed is detected based on the edge width Ed. The value spd can be calculated. Even with this configuration, the same effect as that of the above embodiment can be obtained.

(Third Embodiment)
The third embodiment is shown in FIGS. 11 to 13. As shown in FIG. 11, the output signal synthesis unit 413 of the present embodiment has an XOR circuit which is a logic circuit. FIG. 12 is a diagram corresponding to FIG. 7, and the detection signals Sg1 and Sg2 are the same as those in the first embodiment. When a load due to braking torque is generated in the combined signal Sc_c, the pulse width changes from that in the no-load state. Further, in the combined signal Sc_c generated by the XOR circuit, two pulses correspond to one pulse of the detection signals Sg1 and Sg2, and the edge width Ed_c of the two pulses corresponds to the edge of one pulse of the detection signals Sg1 and Sg2. Matches the width Ed. Therefore, the wheel speed detection value spd can be calculated by using the edge width Ed_c for two pulses of the combined signal Sc_c.

The parameter calculation process of this embodiment will be described with reference to the flowchart of FIG. In S201, the control unit 45 acquires the combined signal Sc_c. In S202, the control unit 45 determines the pulse timing of the combined signal Sc_c. In the pulse timing determination, for example, the pulse shape and phase at no load are stored in advance, and it is determined whether the pulse of the combined signal Sc_c is due to the first detection signal Sg1 or the second detection signal Sg2. Further, the number of pulses of the combined signal Sc_c may be counted, and the pulse timing may be determined according to whether the count number is odd or even.

The processing of S203 to S206 is the same as the processing of S102 to S105 in FIG. In S203 to S207, the calculation is performed according to whether the detected pulse is the first detection signal Sg1 or the second detection signal Sg2. Regarding the torque calculation, when the pulse corresponding to the first detection signal Sg1 is detected, the torque calculation is performed based on the pulse width Pl_1 corresponding to the detection signal Sg1, and when the pulse corresponding to the second detection signal Sg2 is detected. Performs torque calculation based on the pulse width Pl_2 corresponding to the detection signal Sg2. As described above, the wheel speed calculation is performed based on the edge width Ed_c for two pulses.

In at least one of the torque calculation and the wheel speed calculation, for example, the calculation is performed at the timing of pulse detection according to the first detection signal Sg1, and the calculation is skipped at the timing of pulse detection according to the second detection signal Sg2. You may do it. Further, for example, the calculation may be performed at the timing of the second detection signal Sg2, and the calculation may be skipped at the timing of the first detection signal Sg1. Even with this configuration, the same effect as that of the above embodiment can be obtained.

(Fourth Embodiment)
In the fourth embodiment, the logic circuit is an XOR circuit as in the third embodiment. Further, in the present embodiment, the control unit 45 acquires the first detection signal Sg1 before synthesis separately from the synthesis signal Sc_c. Instead of the first detection signal Sc1, the second detection signal Sc2 may be acquired and used. Further, as in the embodiment described later, the control unit 45 may individually acquire the detection signals Sg1 and Sg2, and the control unit 45 may internally generate the combined signal Sc_c.

The parameter calculation process of this embodiment will be described with reference to the flowchart of FIG. The control unit 45 acquires the detection signal Sg1 in S251 and the combined signal Sc_c in S252. In S253, it is determined whether or not it is the rising edge detection timing of the first detection signal Sg1. When it is determined that it is not the rising edge detection timing of the first detection signal Sg1 (S253: NO), the processing after S254 is skipped. When it is determined that it is the rising edge detection timing of the first detection signal S1 (S253: YES), the process proceeds to S254. The processing of S254 to S257 is the same as the processing of S203 to S206. In this embodiment, the wheel speed calculation may be performed using the combined signal Sc_c or the first detection signal Sg1. Further, after the timing determination is performed using the first detection signal Sg1, the calculation may be performed according to the detected pulse as in the third embodiment. Even with this configuration, the same effect as that of the above embodiment can be obtained.

(Fifth Embodiment)
A fifth embodiment is shown in FIGS. 15 and 16. As shown in FIG. 15, in the calculation unit 49 of the present embodiment, the output circuit unit 41 is omitted, and the detection signals Sg1 and Sg2 are not combined and are individually input to the control unit 45.

The parameter calculation process of this embodiment will be described with reference to the flowchart of FIG. In S301, the control unit 45 acquires the detection signals Sg1 and Sg2. In S302, the control unit 45 converts the acquired detection signals Sg1 and Sg2 into a square wave.

In S303, the rotational torque calculation unit 452 calculates the phase difference between the detection signals Sg1 and Sg2. In S304, the rotational torque calculation unit 452 calculates the braking torque detection value trq based on the phase difference between the detection signals Sg1 and Sg2.

In S305, the rotation speed calculation unit 451 calculates the signal cycle of the detection signal Sg1. The detection signal Sg2 may be used instead of the detection signal Sg1. In S306, the rotation speed calculation unit 451 calculates the wheel speed detection value spd based on the signal cycle.

If the detection signals Sg1 and Sg2 converted into square waves are configured to be input to the control unit 45, S302 can be omitted. Further, the phase difference and the signal period may be calculated by frequency analysis or the like without performing the rectangular wave conversion by omitting S302. Further, a synthetic signal may be generated internally and the same calculation as that of the above embodiment may be performed. Even with this configuration, the same effect as that of the above embodiment can be obtained.

(Sixth Embodiment)
A sixth embodiment is shown in FIGS. 17 and 18. The rotation state detection device 130 of the present embodiment calculates the rotation speed and the control drive torque of the in-wheel motor 60 based on the detection values of the first sensor unit 131 and the second sensor unit 132. The in-wheel motor 60 includes a first housing 61, a second housing 62, a stator 65, a rotor 66, and the like.

The first housing 61 has a bottom portion 611, a top portion 613, and a tubular portion 615, is formed in a substantially cylindrical shape, and is fixed to the wheel 92. That is, the first housing 61 rotates integrally with the wheels 92. On the bottom portion 611 provided on the wheel 92 side, a protruding portion 612 constituting the inner ring side of the hub bearing is formed so as to project to the side opposite to the wheel 92. An opening 614 is formed in the top 613.

The second housing 62 has a base portion 621 and a tubular portion 625 provided on the wheel 92 side of the base portion 621. The base portion 621 is formed in a substantially circular shape in a plan view, and is fixed to the vehicle body side by a bearing holding portion 622 (see FIG. 18) protruding outward in the radial direction. In the present embodiment, the bearing holding portion 622 is formed to be relatively narrow. In FIG. 18, bearing holding portions 622 are provided at three locations, but any number may be used as long as it is two or more.

The tubular portion 625 is inserted into the opening 614. A protrusion 612 is inserted into the tubular portion 625 on the tip end side to form the outer ring side of the hub bearing. A ball 63 is provided between the protrusion 612 and the cylinder 625.

The stator 65 is fixed to the radially outer side of the tubular portion 625 of the second housing 62. The rotor 66 is fixed radially inside the tubular portion 615 of the first housing 61, and is rotatably supported by energization of the winding wound around the stator 65. As a result, the rotor 66, the first housing 61, and the wheels 92 rotate integrally by energizing the stator 65. Gears and the like may be appropriately provided between the rotor 66 and the wheels 92.

The rotation state detection device 130 includes a first sensor unit 131, a second sensor unit 132, a magnetic ring 135 as a detection unit, a calculation unit 40, and the like. The magnetic ring 135 is provided on the top 613 of the first housing 61. The sensor units 131 and 132 are provided at the base portion 621 of the second housing 62 so that the change in the magnetic flux due to the rotation of the magnetic ring 135 can be detected.

As shown in FIG. 18, the first sensor unit 131 is provided at an intermediate position between the two bearing holding units 622. It can be said that the intermediate position of the bearing holding portion 622 can be regarded as a non-deformation region Rn in which the deformation due to the braking force is relatively small, and the first sensor portion 131 is provided in the non-deformation region Rn.

The second sensor portion 132 is provided on the opposite side of the first sensor portion 131 with the center point of the base portion 621 interposed therebetween and adjacent to the bearing holding portion 622. The portion adjacent to the bearing holding portion 622 can be regarded as a deformation region Rt in which the deformation due to the braking force is relatively large, and the second sensor portion 132 is provided in the deformation region Rt and is displaced by the braking torque. In FIG. 18, in order to avoid complication, the deformed region Rt and the non-deformed region Rn are described for the locations where the sensor units 131 and 132 are provided.

In the present embodiment, since the first sensor unit 131 is provided in the non-deformable region Rn and the second sensor unit 132 is provided in the deformable region Rt, the distance between the sensors is increased by the control drive torque of the in-wheel motor 60. The phase difference between the detection signal Sg11 of the first sensor unit 131 and the detection signal Sg12 of the second sensor unit 132 changes. If the detection signal Sg1 of the above embodiment is read as the detection signal Sg11 and the detection signal Sg2 is read as the detection signal Sg12, the details of the calculation of the control drive torque detection value trq_d and the wheel speed detection value spd are the same as those of the above embodiment.

The rotation state detection device 130 of the present embodiment is applied to the in-wheel motor 60. The control unit 45 calculates the control drive torque of the in-wheel motor 60 as the torque in the rotation direction of the wheels 92. As a result, the control drive torque of the in-wheel motor 60 can be appropriately calculated.

(Other embodiments)
In the above embodiment, one sensor unit is provided in each of the non-deformable region and the deformable region. In other embodiments, a plurality of sensor units may be provided in at least one of the non-deformable region and the deformable region. In the above embodiment, the detected portion is a magnetic ring and the sensor portion is a magnetic sensor. In another embodiment, the sensor unit may be an optical sensor or the like as long as it can detect the rotation of the wheel. As the detected unit, the one corresponding to the sensor unit may be used. In the above embodiment, the braking device is an electric braking device. In another embodiment, a hydraulic type braking device may be used.

The controls and methods thereof described in the present disclosure are realized by a dedicated computer provided by configuring a processor and memory programmed to perform one or more functions embodied by a computer program. May be done. Alternatively, the controls and methods thereof described in the present disclosure may be implemented by a dedicated computer provided by configuring the processor with one or more dedicated hardware logic circuits. Alternatively, the controls and methods described herein are by a combination of a processor and memory programmed to perform one or more functions and a processor configured by one or more hardware logic circuits. It may be realized by one or more dedicated computers configured. Further, the computer program may be stored in a computer-readable non-transitional tangible recording medium as an instruction executed by the computer. As described above, the present invention is not limited to the above-described embodiment, and can be implemented in various forms without departing from the spirit of the invention.

10 ... Braking device 30, 130 ... Rotational state detection device 31, 131 ... First sensor section 32, 132 ... Second sensor section 35, 135 ... Magnetic ring (detected section)
41 ... Output circuit unit 411 to 413 ... Output signal synthesis unit 45 ... Control unit 451 ... Rotation speed calculation unit 452 ... Torque calculation unit

Claims (8)

The detected parts (35, 135) that rotate integrally with the wheels (92),
The first sensor unit (31, 131) that detects the rotational state of the wheel by detecting the detected unit, and
The second sensor unit (32, 132), which detects the rotational state of the wheel by detecting the detected unit and is provided apart from the first sensor unit,
The torque calculation unit (452) that calculates the torque in the rotational direction of the wheel based on the first detection signal that is the detection signal of the first sensor unit and the second detection signal that is the detection signal of the second sensor unit. The control unit (45) having the
A rotation state detector. The first sensor unit is provided in a non-deformable region where the displacement due to a torque change in the rotational direction of the wheel is relatively small.
The rotational state detecting device according to claim 1, wherein the second sensor unit is provided in a deformed region in which the displacement due to a torque change in the rotational direction of the wheel is relatively large. The first sensor unit and the second sensor unit are wheel speed sensors.
The control unit rotates the wheel based on the signal period of at least one of the first detection signal and the second detection signal, or a signal generated by using the first detection signal and the second detection signal. It has a rotation speed calculation unit (451) that calculates the speed, and has a rotation speed calculation unit (451).
The rotation state detection device according to claim 1 or 2, wherein the torque calculation unit calculates torque in the rotation direction of the wheel based on the phase difference between the first detection signal and the second detection signal. The rotational state detection device according to any one of claims 1 to 3, further comprising an output signal synthesizer (411 to 413) that generates a composite signal obtained by synthesizing the first detection signal and the second detection signal. The rotation state detection device according to claim 4, wherein the output signal synthesis unit has a logic circuit. The combined signal is a square wave signal and
The rotation state detection device according to claim 4 or 5, wherein the torque calculation unit calculates torque in the rotation direction of the wheel based on the pulse width of the combined signal. Applied to the braking device (10),
The rotation state detection device according to any one of claims 1 to 6, wherein the torque calculation unit calculates the braking torque of the braking device as the torque in the rotation direction of the wheel. Applied to in-wheel motor (60)
The rotation state detection device according to any one of claims 1 to 6, wherein the torque calculation unit calculates a control drive torque of the in-wheel motor as a torque in the rotation direction of the wheel.

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