JP5003397B2 - Rotational support device state quantity measuring device - Google Patents

Description

  A state quantity measuring device for a rotation support device according to the present invention includes, for example, a stationary member and a rotation member constituting a rotation support device for rotatably supporting a wheel of a motorcycle (motorcycle, scooter, etc.) with respect to a vehicle body. It is used to measure the relative displacement between these two members and the external force (load, moment) acting between these two members.

[Conventional technology]
For example, the wheels of a four-wheeled vehicle are rotatably supported by a suspension device by a rolling bearing unit such as a double row angular type. In addition, in order to ensure the running stability of automobiles, anti-brake brake system (ABS), traction control system (TCS), and electronically controlled vehicle stability control system (ESC) etc. Is used. In the field of motorcycles, conventionally, a vehicle travel stabilization device such as ABS has been used in order to ensure the vehicle travel stability. In order to control such various vehicle running stabilization devices, signals representing the rotational speed of the wheels, acceleration in each direction applied to the vehicle body, and the like are required. In order to perform more advanced control, it is necessary to know the magnitude of an external force (at least one of a radial load, an axial load and a moment) applied to the rotation support device such as the rolling bearing unit via the wheel. May be preferred.

  In view of such circumstances, for example, in Patent Documents 1 and 2, it is possible to measure an external force acting between a stationary member and a rotating member constituting a rotation support device for a wheel using a special encoder. The invention to be described is described. Each of the conventional structures described in Patent Documents 1 and 2 includes one special encoder that is supported and fixed to the rotating member, and the detection unit facing the detection surface of the encoder. And a plurality of sensors supported and fixed to a portion that does not rotate even when a stationary member or the like is used. The external force can be calculated based on the phase difference between the output signals of the sensors, which changes with the change in the external force (the displacement of the encoder with respect to the stationary member).

  However, each conventional structure described in Patent Documents 1 and 2 is applied to a rotation support device in which a preload is applied to a double row rolling bearing portion, like a rotation support device for a wheel of a four-wheeled vehicle. In this case, the external force can be measured with high accuracy, but when applied to a rotation support device in which preload is not applied to the double row rolling bearing portion, such as a rotation support device for a wheel of some motorcycles. May be difficult to accurately measure the external force. This is because, for example, the axial load acting between the stationary member and the rotating member is calculated based on the phase difference between the output signals of the sensors, which changes with the axial displacement of the encoder. In this case, if no preload is applied to the double row rolling bearing portion, a stable correlation is not established between the axial displacement and the axial load, and the axial load cannot be measured accurately. This is because the possibility increases.

  Further, Patent Document 3 describes a rotation support device that also includes one special encoder and a plurality of sensors. In the case of the conventional structure described in Patent Document 3, the stationary member constituting the rotation support device is based on the phase difference between the output signals of the sensors, which changes with the inclination of the encoder. It is possible to calculate an axial load (or a moment generated based on the axial load) input from a position offset between the rotating member and the central axis of the stationary member in the radial direction. However, even in the case of the conventional structure described in Patent Document 3, the axial load cannot be measured with high accuracy unless a preload is applied, as in the inventions described in Patent Documents 1 and 2 described above. Further, in the case of the conventional structure described in Patent Document 3, the measurement accuracy of the axial load (or moment) with respect to the detection error of the phase difference deteriorates as the diameter of the detection surface of the encoder decreases. The rate increases. For this reason, the conventional structure described in Patent Document 3 is a rotation having a relatively large outer diameter and a relatively large diameter of the detected surface of the encoder to be assembled, like a rotation support device for a wheel of a four-wheeled vehicle. When applied to a support device, the above axial load (or moment) can be measured with high accuracy, but the outer diameter is relatively small, as in the case of a rotation support device for a motorcycle wheel, and the detected encoder is installed. When applied to a rotary support device in which the diameter of the surface must be small, it may be difficult to measure the external force with high accuracy.

[On the structure of the prior invention]
In view of the circumstances as described above, Japanese Patent Application No. 2007-116743 discloses a state quantity measuring device (prior invention device) for a rotary support device as shown in FIGS. 4 to 6 show, as a first example of the device according to the present invention, the prior invention is applied to a rotation support device for rotatably supporting a wheel (front wheel) 1 of a motorcycle with respect to front forks 2 and 2. The case is shown. In a state where both ends of the front forks 2 and 2 are coupled and fixed to the lower ends of the shaft member 3 which is a stationary member which does not rotate during use, and the wheel 1 is supported and fixed on the outer peripheral surface thereof. The hub 4 that is a rotating member that rotates together with the wheel 1 during use is rotatably supported via a pair of rolling bearings 5 and 5. These rolling bearings 5, 5 are provided at both end portions of a cylindrical space existing between the outer peripheral surface of the shaft member 3 and the inner peripheral surface of the hub 4, and are fitted on the shaft member 3. The fixed inner rings 6 and 6 and the outer rings 7 and 7 fitted and fixed to the hub 4 are combined with each other via a plurality of rolling elements (balls) 8 and 8 so as to be concentrically and relatively rotatable. .

Further, in order to position the inner rings 6 and 6 in the axial direction, a tubular spacer 9 fitted and fixed to an intermediate portion of the shaft member 3 and an outer fitting fixed to both ends of the shaft member 3 are fixed. The pair of holding rings 10 and 10 hold the inner rings 6 and 6 from both sides in the axial direction. Further, in order to position the outer rings 7 and 7 in the axial direction, side surfaces of the outer rings 7 and 7 that face each other are formed on stepped surfaces 11 and 11 formed on both ends of the inner peripheral surface of the hub 5. Are abutted through core bars 14 and 14 constituting encoders 13 and 13 respectively described below. In the case of the prior invention device, the preload of the rolling elements (balls) constituting the rolling bearings 5 and 5 may be applied or may not be applied. Further, seal rings 12 and 12 are provided between the outer peripheral surfaces of the holding rings 10 and 10 and the inner peripheral surfaces of both ends of the hub 4 to seal the opening portions of the cylindrical space.

Further, core bars 14 and 14 constituting the encoders 13 and 13 are respectively attached to small-diameter step portions 16 and 16 formed at intermediate portions or one end portions (end portions facing each other) of the outer rings 7 and 7. The outer rings 7 and 7 are fitted and fixed concentrically. In addition, two sensors 19A ₁ and 19A ₂ (19B ₁ and 19B ₂ ) are respectively provided at both end portions of the spacer 9 through support members 20 and 20 that are L-shaped in cross section and configured in an annular shape as a whole. Are supported and fixed. In this state, the detection units of the two sensors 19A ₁ and 19A ₂ (19B ₁ and 19B ₂ ) are opposed to the detection surfaces of the encoders 13 and 13, respectively.

  Both of these encoders 13, 13 are each provided with the core metal 14 and the encoder body 15. Of these, the metal core 14 has an L-shaped cross section made of a magnetic metal plate and is formed in an annular shape as a whole. A cylindrical portion 17 and an annular ring bent at a right angle inward in the radial direction from the end of the cylindrical portion 17. Part 18. The encoder body 15 is made of a permanent magnet and has an annular shape as a whole. The encoder body 15 is formed in the radially inner half of the side surface of the annular portion 18 (the side surface opposite to the cylindrical portion 17 with respect to the axial direction). , It is fixed around the entire circumference. S poles and N poles are alternately arranged at equal intervals in the circumferential direction on the side surface (the side surface opposite to the annular portion 18) of the encoder body 15, which is the detection surface. The boundary between the S pole and the N pole is parallel to the width direction (radial direction) of the detected surface. That is, the phase of the boundary between the S pole and the N pole is not changed in the width direction of the detected surface. The encoders 13 and 13 have the same pitch in the circumferential arrangement of the S pole and the N pole provided on the detected surface.

In the encoders 13 and 13 configured as described above, the cylindrical portions 17 and 17 of the cores 14 and 14 are externally fixed to the small-diameter step portions 16 and 16 of the outer rings 7 and 7 (the hub 4 It is supported and fixed to each of the outer rings 7 and 7 by being internally fitted to the portions near both ends. At the same time, stepped surfaces formed on the outer half portions in the radial direction of the ring portions 18 and 18 of the core bars 14 and 14 on the side surfaces of the outer rings 7 and 7 and on both ends of the inner peripheral surface of the hub 4. 11 and 11, the positioning in the axial direction is achieved. 6A shows a detection surface of the encoder body 15 on the bearing A (the left rolling bearing 5 in FIG. 5) side, and two sensors in which the respective detection portions are opposed to the detection surface. 19A ₁ and 19A ₂ are the same as (B) in which the detection surface of the encoder body 15 on the bearing B (the rolling bearing 5 on the right side in FIG. 5) is made to face the detection surface. FIG. 6 is a projection view of the _two sensors 19B ₁ and 19B ₂ as viewed from the right side (+ y side) in FIG. 5 (the same applies to FIGS. 7 to 13 described later). As shown in FIG. 6, in the case of this example, in the state where both the encoders 13 and 13 are assembled to the rotation support device as described above, the S pole existing on the detected surface of both the encoders 13 and 13 is used. The encoders 13 and 13 are made to coincide with each other in the circumferential arrangement phase of the N pole and the N pole.

In addition, magnetic detection elements such as a Hall IC, a Hall element, an MR element, and a GMR element are incorporated in the detection portions of the sensors 19A ₁ , 19A ₂ , 19B ₁ , and 19B ₂ . Of the three-dimensional orthogonal coordinate system composed of the x-axis, y-axis, and z-axis that are orthogonal to each other, the y-axis is the central axis of the shaft member 3, the z-axis is the vertical axis, and the x-axis is the front-rear axis. In this case, in the neutral state where no external force is acting between the shaft member 3 and the hub 4, as shown in FIG. The detectors of the sensors 19A ₁ , 19A ₂ , 19B ₁ , and 19B ₂ are opposed to each other at two positions (θ = 90 °, 270 ° positions) opposite to each other in the radial direction. In FIG. 6, when the sensors 19A ₁ and 19A ₂ are located on the front side of the detected surface (A), the sensors 19A ₁ and 19A ₂ are black circles, and the back side of the detected surface. In (B) where the sensors 19B ₁ and 19B ₂ are located, these sensors 19B ₁ and 19B ₂ are represented by white circles (the same applies to FIGS. 7 to 13 described later).

An arithmetic unit 21 is supported and fixed on the upper surface of the central portion in the axial direction of the spacer 9. Further, a key groove-shaped groove portion 22 is provided in an axial middle portion or one end portion (right end portion in FIG. 5) of the upper surface of the shaft member 3. At the same time, a through hole 23 is provided in the upper end portion of the spacer 9 so as to be aligned with the other end portion (left end portion in FIG. 5) of the groove portion 22 in the radial direction. Various cables (not shown) connected to the computing unit 21 (for example, signals representing computation results such as displacement, inclination, load, moment, etc. described later by the computing unit 21, and the sensors 19A ₁ , 19A ₂ , 19B ₁ and 19B ₂ , a signal cable for transmitting a pulse waveform signal (slip rate control signal) of at least one sensor to the ABS controller, a power cable for supplying power to the computing unit 21, etc. These are pulled out to the outside through the through hole 23 and the groove 22 so that they can be connected to various devices (for example, an ABS controller and a power supply device) on the vehicle body side.

In the state quantity measuring device of the rotary support device of the prior invention configured as described above, the two sensors 19A ₁ and 19A ₂ are accompanied by the occurrence of the displacement z _A in the z-axis direction in the encoder 13 on the bearing A side. the phase difference change of the output signal, with the possible displacement z _B in the same direction to the encoder 13 of the bearing B side occurs, a phase difference between the two sensors 19B _1, 19B ₂ of the output signal is changed. On the other hand, even if a displacement y in the y-axis direction occurs in each encoder 13, 13, only the distance between each detection surface and each detection unit changes, and each phase difference does not change. Furthermore, even if the displacements x in the x-axis direction occur in the encoders 13 and 13, the respective phase differences are not changed. Therefore, in the case of the state quantity measuring device for the rotary support device of the above invention, the displacement z _A and z _B of the encoders 13 and 13 in the z-axis direction can be detected based on each phase difference. The displacement z of the center 4 (the geometric center between the encoders 13 and 13) O and the inclination φ _x of the hub 4 around the x-axis can be obtained.

従って、これら（１）〜（２）式に上記両位相差比ε_A1-A2 、ε_B1-B2 を代入し、これら（１）〜（２）式を演算器２１に計算させる事により、上記ハブ４の中心Ｏの変位ｚと、このハブ４の傾きφ_x とを求める事ができる。 Specifically, the pitch circle diameter (PCD) of the detected surfaces of the encoders 13 and 13 is d, and the number of S-pole and N-pole pairs (one rotation) arranged on the entire circumference of each detected surface. (The number of pulses of the output signal of each sensor per unit) is n, and the interval (span) between the detected surfaces is L (the meanings of these d, n, and L are described in the following examples). The difference Δt / T (phase difference ratio) obtained by dividing the pulse edge time difference Δt (phase difference) of the output signals of the _two sensors 19A ₁ and 19A ₂ by the pulse period T is defined as ε _{A1 -A2} . When the phase difference ratio of the output signals of the _two sensors 19B ₁ and 19B ₂ is defined as ε _{B1 -B2} , the displacement z of the center O of the hub 4 and the inclination φ _{x of the} hub 4 are respectively It is represented by formulas (1) to (2).

Therefore, by substituting the two phase difference ratios ε _{A1 -A2} and ε _B1 -B2 into these equations (1) and (2) and letting the computing unit 21 calculate these equations (1) and (2), The displacement z of the center O of the hub 4 and the inclination φ _{x of the} hub 4 can be obtained.

In the case of a rotation support device for a motorcycle, the displacement z of the center O of the hub 4 and the radial load Fz acting in the z-axis direction acting between the hub 4 and the shaft member 3, and the inclination phi _x of the hub 4, acting between the hub 4 and the shaft member 3, in the y-axis direction is input from the ground surface of the tire which constitutes the wheel in the axial load Fy (or the axial load Fy A correlation is established with the moment Mx) around the x-axis generated based on this. The reason for this is that, in the case of a rotary support device to which no preload is applied as in this example, the radial gap between the pair of rolling bearings 5 and 5 (bearings A and B) is smaller than the axial gap, and Normally, since the radial load Fz based on the weight of the vehicle body acts on the rolling bearings 5 and 5, the radial displacements of the encoders 13 and 13 are the radial load Fz and the axial load Fy (moment Mx). This is because it is less likely to fluctuate regardless of. Therefore, in this example, the arithmetic unit 21 can calculate the radial load Fz based on the displacement z of the center O of the hub 4. At the same time, the axial load Fy (moment Mx) can be calculated based on the inclination φ _{x of the} hub 4. Each of the above correlations can be obtained not only by calculation based on the elastic contact theory widely known in the field of rolling bearing units, but also by experiments (shipment test).

As described above, in the state quantity measuring device of the rotary support device of the previous invention, the phase difference between the output signals of the _two sensors 19A ₁ and 19A ₂ on the bearing A side and the bearing B side It is only necessary to measure the phase difference between the output signals of the _two sensors 19B ₁ and 19B ₂ , and there is no need to measure the phase difference between the sensors straddling both sides. For this reason, the rotation angle position when assembling the encoders 13 and 13 and the outer rings 7 and 7 on both sides is regulated, and the initial phase difference between the sensors across both sides is set to a predetermined size. No need to do work. Therefore, the assembly can be easily performed by that amount.

FIG. 7 shows another example (second example) of the state quantity measuring device for the rotary support device of the previous invention. In the case of this example, in the neutral state, out of the detected surfaces of the pair of encoders 13 and 13, at two positions (θ = 0 degrees, 180 degrees) on the opposite side in the radial direction on the z axis. Each one of the sensors 19A ₁ , 19A ₂ , 19B ₁ , 19B ₂ is made to face each other. In other words, in comparison with the first example described above, the detection units of the sensors 19A ₁ , 19A ₂ , 19B ₁ , 19B ₂ are respectively opposed to positions shifted by 90 degrees (positions obtained by 90-degree coordinate conversion). Yes. For this reason, in the case of this example, the displacement x in the x-axis direction of the center O of the hub 4 (see FIG. 5) relative to the shaft member 3 and the hub 4 on the same principle as in the case of the first example described above. The inclination φ _z around the z-axis can be calculated. Further, based on the displacement x of the center O of the hub 4 in the x-axis direction, the radial load Fx in the x-axis direction acting between the hub 4 and the shaft member 3 can be calculated. At the same time, based on the inclination φ _z of the hub 4, the moment Mz about the z-axis acting between the hub 4 and the shaft member 3 can be calculated.

FIG. 8 shows another example (third example) of the state quantity measuring device of the rotary support device of the previous invention. In the case of this example, the number of the detecting portion of the first sensor 19A ₁ through 19a ₃ which is opposed to the detected surface of the pair of the encoder 13, 13, 19B ₁ through 19b ₃ are shown in Figures 4-6 of the aforementioned Different from the case of one example. That is, in the case of this example, three positions (θ = 60 degrees, 180 degrees, 300 degrees) at equal intervals in the circumferential direction on the detected surfaces of the pair of encoders 13, 13 in the neutral state. ), Each of the sensors 19A _{1 to} 19A ₃ and 19B _{1 to} 19B ₃ are opposed to each other. In the case of this example configured as described above, when an external force acts between the shaft member 3 and the hub 4 and a radial displacement occurs in both the encoders 13 and 13, the sensors 19 A ₁ to 19 A ₁ . The phases of the output signals 19A ₃ and 19B _{1 to} 19B ₃ are shifted. Here, this phase shift is expressed by a phase difference ratio ε (θ) obtained by dividing the phase difference by one period, and the radial displacements of the encoders 13 and 13 in the x-axis direction and the z-axis direction are respectively X and Z. Then, the phase difference ratio ε (θ) is expressed by the following equation (3).

これら（４）〜（７）式の関係より、上記各エンコーダ１３、１３のラジアル変位（ｘ_A 、ｚ_A ）、（ｘ_B 、ｚ_B ）は、それぞれ次の（８）〜（９）式により算出できる。

又、この様に各エンコーダ１３、１３のラジアル変位（ｘ_A 、ｚ_A ）、（ｘ_B 、ｚ_B ）が求まれば、上記ハブ４の中心Ｏの変位ｘ、ｚ及び傾きφ_x 、φ_z は、それぞれ次の（１０）〜（１３）式により算出できる。

Here, the radial displacements of the encoder 13 on the bearing A side in the x-axis direction and the z-axis direction are x _A and z _A , respectively, and the radial displacements of the encoder 13 on the bearing B side in the x-axis direction and z-axis direction are respectively represented. Let x _B and z _B be the same. Then, each of these radial displacement _{x A, z A, x B} , caused by z _B, a phase difference ratio between an output signal with each other, each two sensors, the two sensors A _2, A place between ₁ The phase difference ratio ε _A2 -A1, the phase difference ratio ε _A2 -A3 between the two sensors A ₂ and A ₃ , the phase difference ratio ε _B2 -B1 between the two sensors B ₂ and B ₁ , and the two sensors B The phase difference ratio ε _B2 -B3 between ₂ and B ₃ can be expressed by the following equations (4) to (7) based on the above equation (3).

From the relationship of these equations (4) to (7), the radial displacements (x _A , z _A ) and (x _B , z _B ) of the encoders 13 and 13 are respectively expressed by the following equations (8) to (9). Can be calculated.

When the radial displacements (x _A , z _A ) and (x _B , z _B ) of the encoders 13 and 13 are obtained in this way, the displacement x and z and the inclinations φ _x and φ of the center O of the hub 4 are obtained. _z can be calculated by the following equations (10) to (13).

Furthermore, also in this example, based on the displacement x of the center O of the hub 4 in the x-axis direction, the radial load Fx acting between the hub 4 and the shaft member 3 (see FIG. 5) is Based on the displacement z in the z-axis direction of the center O of the hub 4, a radial load Fz acting between the hub 4 and the shaft member 3 is determined based on the inclination φ _x of the hub 4 and the hub 4. the x-axis moment Mx acting between the shaft member 3, on the basis of the inclination phi _z of the hub 4, z axis moment Mz acting between the hub 4 and the shaft member 3 ( Axial loads Fy) can be calculated respectively.
In the above-described third example, the circumferential positions of the detection units of the _three sensors 19A _{1 to} 19A ₃ (19B _{1 to} 19B ₃ ) are set at equal intervals. If the above equations (4) to (9) are corrected in accordance with a proper arrangement, the above-described displacement, inclination, load, and moment can be obtained.

Next, FIG. 9 shows another example (fourth example) of the state quantity measuring device of the rotation support device of the previous invention. In the case of this example, the number of detection parts of the sensors 19A ₁ and 19B ₁ opposed to the detected surfaces of the pair of encoders 13 and 13 is different from the case of the first example shown in FIGS. . That is, in the case of this example, in the neutral state, each of the detected surfaces of the pair of encoders 13 and 13 is located at one position on the x-axis (position of θ = 90 degrees). The detection parts of the sensors 19A ₁ and 19B ₁ are opposed to each other.

更に、このハブ４の傾きφ_x に基づいて、上記軸部材３とこのハブ４との間に作用するアキシアル荷重Ｆｙ（又はｘ軸回りのモーメントＭｘ）を精度良く算出できる。 In the case of this example configured as described above, the inclination of the hub 4 (see FIG. 5) about the x-axis with respect to the shaft member 3 based on the phase difference between the output signals of these sensors 19A ₁ and 19B ₁ . φ _x can be obtained. That is, in the case of this example, the bearing 13 side encoder 13 and the bearing B side encoder 13 are mutually connected in the z-axis direction as the inclination φ _{x of the} hub 4 with respect to the shaft member 3 is generated. Displaces in the opposite direction. As a result, the phase difference between the output signals of both the sensors 19A ₁ and 19B ₁ changes. On the other hand, even if a displacement x occurs in the hub 4 (both encoders 13 and 13) with respect to the shaft member 3, the phase difference does not change. Further, even if the axial displacement y or the inclination φ _z around the z axis occurs in the hub 4 (both encoders 13 and 13) with respect to the shaft member 3, the distance between each detected surface and each detecting portion is maintained. Only the change does not change the phase difference. Even if a displacement z in the z-axis direction occurs in the hub 4 (both encoders 13 and 13) with respect to the shaft member 3, the phases of the output signals of the sensors 19A ₁ and 19B ₁ are in the same direction. The phase difference does not change only by changing by the same magnitude. Therefore, in the case of this example, based on the phase difference, the inclination phi _x of the hub 4 (without being influenced by the other direction of displacement and tilt) can be obtained.
Specifically, if the phase difference ratio between the output signals of the two sensors 19A ₁ and 19B ₁ is defined as ε _B1-A1 , the inclination φ _{x of the} hub 4 can be obtained by the following equation (14). it can.

Further, the axial load Fy (or moment Mx around the x axis) acting between the shaft member 3 and the hub 4 can be calculated with high accuracy based on the inclination φ _x of the hub 4.

Incidentally, as described above, in the case of this example, exists between the output signal of the sensor 19B ₁ of the output signal of the sensor 19A ₁ of the bearing A side and the bearing B side, necessary to measure the phase difference There is. For this reason, the rotational angle position when assembling the encoders 13 and 13 and the outer rings 7 and 7 (see FIG. 5) on both sides is regulated, and the initial phase difference between the output signals of both the sensors 19A ₁ and 19B ₁ is predetermined. It is necessary to set to the size of. In this case, as a method of restricting the rotational angle position, for example, the encoders 13 and 13 are set to the outer rings 7 and 7, and the outer rings 7 and 7 are set to the hub 4 as desired. A method of providing a guide such as a key engaging portion for enabling fitting at a rotational angle position can be adopted.

Next, FIG. 10 shows another example (fifth example) of the state quantity measuring device of the rotary support device of the previous invention. In the case of this example, the opposing positions of the detection units of the sensors 19A ₁ and 19B ₁ with respect to the detected surfaces of the pair of encoders 13 and 13 are different from the case of the fourth example of the above-described embodiment. That is, in the case of this example, in the neutral state, one of the detected surfaces of the pair of encoders 13 and 13 is located at one position on the z-axis (position of θ = 180 degrees). The detection parts of the sensors 19A ₁ and 19B ₁ are opposed to each other. In other words, in comparison with the fourth example of the above-described embodiment, the detection units of the sensors 19A ₁ and 19B ₁ are opposed to positions shifted by 90 degrees (positions obtained by 90-degree coordinate conversion). Therefore, in this example, the inclination φ _z around the z axis of the hub 4 (see FIG. 5) with respect to the shaft member 3 can be calculated on the same principle as in the fourth example of the above-described embodiment. . Further, based on the inclination φ _z of the hub 4, a moment Mz about the z axis acting between the shaft member 3 and the hub 4 can be calculated.

Next, FIG. 11 shows another example (sixth example) of the state quantity measuring device of the rotary support device of the previous invention. In the case of this example, a structure combining the structure of the fourth example and the structure of the fifth example of the above-described invention structure is adopted. That is, in the case of this example, in the neutral state, one position on the x-axis (position of θ = 90 degrees) and one position on the z-axis among the detected surfaces of the pair of encoders 13 and 13. The detectors of the sensors 19A ₁ , 19A ₂ , 19B ₁ , 19B ₂ are made to face each other (one position at θ = 180 degrees). In the case of this example configured as described above, the inclination of the hub 4 (see FIG. 5) with respect to the shaft member 3 around the x-axis is based on the same principle as that of the fourth to fifth examples of the above-described invention structure. and phi _x, of the z-axis and a tilt phi _z can be calculated. Furthermore, on the basis of the inclination phi _x and tilt phi _z of the hub 4, it can be calculated and axial load Fy (moment Mx) and moment Mz acting between respectively the shaft member 3 and the hub 4.

更に、この変位ｚから、上記軸部材３とハブ４との間に作用する、ｚ軸方向のラジアル荷重Ｆｚを求める事ができる。 In the case of the sixth example described above, the two sensors 19A ₁ on the bearing A side are accompanied by the occurrence of the displacement x in the x-axis direction or the displacement z in the z-axis direction at the center O of the hub 4. The phase difference between 19A ₂ (phase difference ratio ε _A1-A2 ) and the phase difference between the _two sensors 19B ₁ and 19B ₂ on the bearing B side (phase difference ratio ε _B1-B2 ) change. However, each of these phase differences changes with both displacements x and z. For this reason, it is not possible to measure these displacements x and z separately from each phase difference. However, if it is an application in which only one of these two displacements x and z is generated in use, the displacement can be measured from each of the phase differences. For example, in an application where the displacement x is 0 in use, the displacement z can be calculated by the following equation (15).

Furthermore, the radial load Fz in the z-axis direction acting between the shaft member 3 and the hub 4 can be obtained from the displacement z.

Next, FIG. 12 shows another example (seventh example) of the state quantity measuring device of the rotary support device of the previous invention. In the case of this example, the number of sensors opposed to the surface to be detected of the encoder 13 on the bearing B side is different from that in the first example. That is, in the case of this example, in the neutral state, on the detection target surface of the encoder 13 on the bearing A side, there are two positions (θ = 90 degrees, 270 degrees positions) on the x axis on the opposite side in the radial direction. Each of the sensors 19A ₁ and 19A ₂ are opposed to each other. On the other hand, the detection portion of _one sensor 19B ₁ is opposed to the detected surface of the encoder 13 on the bearing B side only at one position on the x-axis (position of θ = 90 degrees).

更に、この変位ｚから、上記軸部材３とハブ４との間に作用する、ｚ軸方向のラジアル荷重Ｆｚを、上記傾きφ_x から、これら軸部材３とハブ４との間に作用するアキシアル荷重Ｆｙ（又はｘ軸回りのモーメントＭｘ）を、それぞれ求める事ができる。 In the case of this example configured as described above, the center O of the hub 4 with respect to the shaft member 3 (see FIG. 5) based on the phase difference between the output signals of the sensors 19A ₁ , 19A ₂ , 19B ₁ . The displacement z in the z-axis direction and the inclination φ _x about the x-axis of the hub 4 are obtained. That is, in the case of this example, as in the case of the fourth example shown in FIG. 9, the two sensors 19A ₁ and 19B ₁ facing the same position in the circumferential direction on the bearing A side and the bearing B side are provided. Based on the phase difference between them (phase difference ratio ε _B1-A1 ), the inclination φ _x of the hub 4 around the x axis can be obtained. Further, as in the case of the first example described above, the encoder 13 on the bearing A side is controlled based on the phase difference between the _two sensors 19A ₁ and 19A ₂ on the bearing A side (phase difference ratio ε _{A1 -A2} ). _A displacement z _A in the z-axis direction is obtained. Therefore, on the basis of the displacement z _A and the inclination phi _x, the center O of the hub 4, is determined the displacement z of the z-axis direction. Specifically, this displacement z can be calculated by the following equation (16).

Further, from this displacement z, a radial load Fz acting between the shaft member 3 and the hub 4 in the z-axis direction is changed from an inclination φ _x to an axial acting between the shaft member 3 and the hub 4. The load Fy (or the moment Mx around the x axis) can be obtained.

Next, FIG. 13 shows another example (eighth example) of the state quantity measuring device of the rotary support device of the previous invention. In the case of this example, the opposing positions of the detection portions of the sensors 19A ₁ , 19A ₂ , 19B ₁ with respect to the detected surfaces of the pair of encoders 13 and 13 are different from those in the seventh example described above. That is, in the case of this example, in the neutral state, among the detected surfaces of the encoder 13 on the bearing A side, two positions on the z axis that are radially opposite to each other (positions of θ = 0 degrees and 180 degrees) Each of the sensors 19A ₁ and 19A ₂ are opposed to each other. At the same time, the detection part of _one sensor 19B ₁ is made to face one position (position of θ = 180 degrees) on the z-axis on the detected surface of the encoder 13 on the bearing B side. In other words, in comparison with the seventh example described above, the detection units of the sensors 19A ₁ , 19A ₂ , and 19B ₁ are opposed to positions that are shifted by 90 degrees (positions that have undergone 90-degree coordinate conversion). For this reason, in the case of this example, the displacement x in the x-axis direction of the center O of the hub 4 (see FIG. 5) with respect to the shaft member 3 and the hub 4 on the principle similar to the case of the seventh example described above. The inclination φ _z around the z axis can be calculated. Further, based on the displacement x of the center O of the hub 4, the radial load Fx acting between the shaft member 3 and the hub 4 is changed based on the inclination φ _{z of the} hub 4 with the shaft member 3. The moments Mz acting between the hub 4 and the hub 4 are respectively determined.

Next, FIG. 14 shows another example (9th example) of the state quantity measuring device of the rotation support device of the previous invention. In the case of this example, a pair of encoders 13 and 13 are fitted and fixed to portions near both ends of the hub 4 in the axial direction. Moreover, the calculator 21 (refer FIGS. 4-5) is not installed in the upper surface of the axial center part of the cylindrical spacer 9. FIG. In the case of this example, this computing unit 21 is installed on a part of the vehicle body {for example, a part of the front fork 2 (see FIG. 5), the vicinity of the ABS controller, or the inside of the ABS controller}. is doing. Further, in the case of this example, a cable (not shown) connected to the sensors 19A _1, 19B ₁ (these output signals of the sensors 19A _1, 19B _1, the signal cable to be transmitted to the computing unit 21 and the ABS controller) To the outside through the through hole 23 formed in the spacer 9 and the groove 22 formed in the shaft member 3 so that it can be connected to various devices on the vehicle body side (for example, the arithmetic unit 21 and the ABS controller). I have to. In the case of this example, a structure in which both the encoders 13 and 13 are fitted and fixed to the hub 4 in advance is adopted, so that the phase alignment of the encoders 13 and 13 in the circumferential direction can be easily performed. Yes.

  In each example described above, the initial phase difference between the output signals of the sensors is set to zero. However, if the initial phase difference between these sensors is set to a predetermined magnitude, it is possible to prevent the pulse edge timing of the output signal from being reversed (passing of the pulse edge) between these sensors during use. . Therefore, it is possible to normally detect the phase difference between the sensors without monitoring the presence or absence of the reverse rotation. Further, in this case, the pulse waveforms of the output signals of a plurality of sensors whose phases do not coincide with each other in use are used (use of those obtained by multiplying the pulse waveforms of the output signals of the plurality of sensors). If the slip ratio control of the wheel by ABS is performed, this slip control can be performed more accurately than when the slip control is performed using only the pulse waveform of the output signal of one sensor.

Further, in each of the above examples, the detection surfaces of the pair of encoders are each in the shape of a ring, and the structure in which the detection part of each sensor is opposed to both the detection surfaces in the axial direction is employed. The invention can also employ a structure in which the detection surfaces of the pair of encoders are cylindrical, and the detection portions of the sensors face the detection surfaces in the radial direction. For example, as a combination of one of the encoder and the sensor, such as shown in FIG. 15, it is also possible to employ a combination of the encoder 13a and six sensors 19A ₁ through 19a _6. Of these, the encoder 13a is entirely cylindrical. Then, S poles and N poles are alternately arranged at equal intervals in the circumferential direction on the outer peripheral surface, which is the detected surface, and both axial halves of the detected surface are respectively connected to the S pole and N pole. The first and second characteristic changing sections 24 and 25 are configured such that the phase at the boundary with the pole gradually changes at the same angle in opposite directions with respect to the axial direction. Of the sensors 19A _{1 to} 19A ₆ , the detection unit of _one sensor 19A ₁ is used as the first characteristic change unit 24, and the detection unit of another sensor 19A ₂ is used as the second characteristic change unit. 25, the detection portions of the remaining sensors 19A _{3 to} 19A ₆ are connected to the portions of the first characteristic changing portion 24 or the second characteristic changing portion 25 where the phase in the circumferential direction coincides with the sensor 19A _1. It is made to oppose to the part spaced apart in the circumferential direction with respect to the part which the detection part of another sensor opposes, respectively. If such a structure is adopted, each is a phase difference existing between the output signals of two sensors selected from the _six sensors 19A _{1 to} 19A ₆ , and they are different from each other. Based on the five phase differences relating to the combination of two sensors, the displacement x in the x-axis direction, the displacement y in the y-axis direction, the displacement z in the z-axis direction, and the inclination around the x-axis of the encoder 13a φ _x and the inclination φ _z around the z axis can be calculated respectively.

  In each example described above, the encoder is made of a permanent magnet, the first characteristic portion provided on the detection surface of the encoder is a portion magnetized to the S pole, and the second characteristic portion is magnetized to the N pole. The structure which makes it a part is adopted. However, when carrying out the prior invention, the encoder is made of a simple magnetic metal plate, the first characteristic portion provided on the detection surface of the encoder is a through hole (or a concave portion), and the second characteristic portion is a column portion. It is also possible to adopt a configuration that is (or a convex portion). When such a configuration is adopted, a permanent magnet is incorporated on each sensor side.

  Furthermore, in each example described above, after calculating the displacement and inclination of the hub 4 based on the phase difference between the sensors, the external force acting between the shaft member 3 and the hub 4 is applied based on the displacement and inclination. A calculation configuration is adopted. However, if only the measurement of the external force is intended, the external force can be directly obtained based on the phase difference between the sensors without calculating the displacement and inclination. In this case, the relationship between the external force and the phase difference between the sensors is examined by a shipping test performed by actually applying the external force, and this relationship is used.

[Points where improvement is desired in the structure of the prior invention]
The above-described state quantity measuring device for the rotation support device according to the invention as described above is such a stationary member when a load is applied between the stationary member such as the shaft member 3 and the rotating member such as the hub 4. The relative displacement between the rotating member and the rotating member is measured, and this load is estimated. In this case, from the viewpoint of ensuring the measurement accuracy of the load, it is preferable to use the rolling bearings 5 and 5 provided with preloads on the balls (rolling elements) 8 and 8. The reason for this is as follows. The magnitude of the relative displacement amount between the two members 3 and 4 when a load is applied between the shaft member 3 and the hub 4 is provided between the two members 3 and 4. It is almost inversely proportional to the rigidity of the rolling bearings 5 and 5. The rigidity of the rolling bearings 5 and 5 increases as the preload increases.

  The rolling bearings 5 and 5 are rolling bearings that constitute a rotation support device for rotatably supporting a wheel including a motorcycle, even if a bearing that does not apply preload to the balls 8 and 8 is used. In this case, in use, a load similar to the preload continues to be applied to the balls 8 and 8 existing in the load zone (the lower portion in the case of the outer ring rotating type wheel rotation support device). However, a load such as a preload is not applied to the balls 8 and 8 existing in the non-load zone (upper side or both side portions in the same case). In other words, there is a positive gap between the rolling surfaces of the balls 8, 8 existing in the non-load zone and the inner ring raceway 26 provided on the outer peripheral surface of the inner ring 6 or the outer ring raceway 27 provided on the inner peripheral surface of the outer ring 7. (One or both of a radial gap and an axial gap) is present. In such a state, even if the magnitude and direction of the load (moment) applied between the members 3 and 4 are slightly changed, the members 3 and 4 are easily relatively displaced. As a result, the relationship between the load applied between the members 3 and 4 and the relative displacement between the members 3 and 4 becomes complicated, and the load applied between the members 3 and 4 can be accurately calculated. It becomes difficult to ask.

  On the other hand, if the rolling bearings 5 and 5 are each provided with a preload applied to the balls 8 and 8, the rolling surfaces and inner ring raceways of the balls 8 and 8 are also applied to the non-load zone. 26 and the outer ring raceway 27 can be prevented from having a positive gap. The relationship between the magnitude and direction of the load applied between the members 3 and 4 and the magnitude and direction of the relative displacement between the members 3 and 4 is simpler than when no preload is applied. Thus, the load applied between the members 3 and 4 can be easily obtained with high accuracy. However, this load can be obtained with high accuracy under the condition that the preload applied to the balls 8 and 8 is stable. If this preload changes due to a temperature change or the like, the rigidity of the rolling bearings 5 and 5 may change, and the measurement accuracy of the load based on the magnitude and direction of relative displacement between the members 3 and 4 may deteriorate. There is.

  On the other hand, as shown in FIGS. 4 to 5 and 14 described above, a pair of rolling bearings 5 and 5 constituting a rotation support device for rotatably supporting the wheels of the motorcycle with respect to the vehicle body are provided for each outer ring. 7 and 7 are fitted in the hub 4, and the respective inner rings 6 and 6 are fitted on the shaft member 3. Further, these outer rings 7 and 7 are brought into contact with the stepped surfaces 11 and 11 formed on the inner peripheral surface of the hub 4 with the axial end surfaces facing each other directly or via the core bars 14 and 14, respectively. Displacement in the direction of approaching each other is limited. In this state, in order to apply a preload to the balls 8 and 8 of the both rolling bearings 5 and 5, the inner rings 6 and 6 are moved in the above-described state while the inner rings 6 and 6 are pressed in a direction approaching each other. It is fixed to the shaft member 3. In this state, a preload is applied to each of the balls 8 and 8 together with a contact angle of a rear combination type (DB type). If the preload is constant in this state, the relationship between the magnitude and direction of the load and the magnitude and direction of the relative displacement can be stabilized, and the measurement accuracy of the load based on the relative displacement can be improved.

  However, when the motorcycle is running, the temperature of the shaft member 3 and the hub 4 rises due to radiant heat from the road surface, heat generation based on the rolling resistance inside the rolling bearings 5 and 5, and the like. If the material of the shaft member 3 and the hub 4 and the degree of temperature rise are the same, the preload hardly changes and the load can be measured with high accuracy. However, in order to ensure strength and rigidity, the shaft member 3 is generally made of an iron-based alloy such as carbon steel or stainless steel, and the hub 4 is made of an aluminum-based alloy or magnesium for weight reduction. Often made from light metals such as alloys. In this case, the amount of thermal expansion accompanying a rise in temperature is greater in the hub 4 than in the shaft member 3, and the preload tends to change with the difference in the amount of thermal expansion. Specifically, with respect to the radial direction (radial direction), the distance between the inner peripheral surface of the hub 4 and the outer peripheral surface of the shaft member 3 increases, and the preload tends to decrease. Further, with respect to the axial direction, the extent to which the distance between the pair of outer rings 7, 7 supported by the hub 4 increases is greater than the extent to which the distance between the pair of inner rings 6, 6 supported by the shaft member 3 increases. Will also be remarkable. And when the contact angle of the back combination type is given to each of the balls 8, 8, the preload tends to increase in the axial direction (axial direction).

  As described above, the balls 8, 8 constituting the pair of rolling bearings 5, 5 provided between the outer peripheral surface of the shaft member 3 made of iron-based alloy and the inner peripheral surface of the hub 4 made of light alloy. The preload to be applied tends to change as the temperature rises. Also, the tendency to change (increase / decrease) the preload is opposite between the radial direction and the axial direction. However, although it depends on the contact angle given to each of the balls 8 and 8, a general (for example, a contact angle of about 25 to 45 degrees is included) including a case of a rotation support device for supporting a wheel of a motorcycle. In the case of the rolling bearings 5, 5, the degree to which the preload changes with the dimensional change in the radial direction is smaller than the degree to which the preload changes with the dimensional change in the axial direction. This is because the difference in axial dimension between the shaft member 3 and the hub 4 directly leads to a change in preload, whereas a radial dimension change does not directly lead to a change in preload. is there. That is, the dimensional change in the radial direction first leads to elastic deformation of the members 3 and 4 and the track rings 6 and 7, and the diameter change of the track rings 6 and 7 is the first time the preload is changed. Because it leads to change. In other words, a considerable portion of the dimensional change in the radial direction of both the members 3 and 4 is consumed by the change in the tightening margin of the fitting portion between the both members 3 and 4 and the race rings 6 and 7. Only a part of the change in the preload is connected. Therefore, the change amount of the difference between the outer diameters of the inner rings 6 and 6 and the inner diameters of the outer rings 7 and 7 due to the temperature change is smaller than the change amount of the difference between the inner and outer diameters of the members 3 and 4. .

  As can be seen from these facts, when the temperature rises, the tendency to change the preload in the radial direction and the axial direction is opposite to each other, but the degree is different. Changes due to expansion and contraction become dominant. Specifically, in the case where a contact angle of the back combination type is given to the balls 8, 8 constituting the both rolling bearings 5, 5, when the temperature of both the members 3, 4 increases similarly, the axial direction Tend to increase the preload. Only a part of the increase in the preload is offset by the decrease in the preload accompanying the dimensional change in the radial direction of the members 3 and 4. Eventually, the preload applied to the balls 8 and 8 constituting the rolling bearings 5 and 5 increases when the temperature rises.

  The amount of change in the preload accompanying the temperature change is limited, and the influence on the performance including dynamic torque and durability of the rotation support device of various mechanical devices including motorcycles is limited. However, in the state quantity measuring device of the rotary support device according to the above-described invention, the change in the support rigidity accompanying the change in the preload directly leads to an error in the measured value. For this reason, in order to ensure the accuracy of the measurement value, it is desired to realize a structure that can suppress the change in the preload. However, for example, in the case of a rotation support device for a motorcycle wheel, it is required for at least one of the members 3 and 4 to make the shaft member 3 and the hub 4 from the same material. It is preferable to avoid this because it may sacrifice the performance.

JP 2006-133045 A JP 2006-322928 A JP 2007-93580 A

  In view of the circumstances as described above, the state quantity measuring device of the rotation support device according to the present invention is a stationary member that is relatively rotatably supported by a double row rolling bearing device like a rotation support device for a wheel of a motorcycle. Even if the material of the rotating member and the material of the rotating member are different from each other, the rotation support device is configured to suppress the change in the preload applied to each rolling element, constituting the double row rolling bearing device, regardless of the temperature change. The invention was invented to realize a structure capable of accurately measuring an external force acting between a stationary member and a rotating member.

The state quantity measuring device for a rotation support device of the present invention includes a rotation support device and a state quantity measurement device.
Among these, the rotation support device is provided with a pair of stationary side tracks on the stationary side circumferential surface, a stationary member that does not rotate even when in use, and a pair of rotation side tracks on the rotating side circumferential surface, which rotates when in use. A member, and a plurality of rolling elements are provided between the rotating side tracks and the stationary side tracks.
In addition, the state quantity measuring device includes a pair of encoders that are supported at two positions separated from each other in the axial direction of the rotating member and rotate together with the rotating member, and a sensor that is supported and fixed to a portion that does not rotate even when used. A device and a computing unit.
Each of the pair of encoders has a detected surface concentric with the rotating member, and the characteristics of both the detected surfaces are alternately changed at the same pitch in the circumferential direction.
In the sensor device, one or a plurality of sensors having a detection unit opposed to a detection surface of one of the encoders, and a detection unit having a detection unit opposed to a detection surface of the other encoder. Or a plurality of sensors, each of which changes an output signal in response to a characteristic change of a portion of the detected surfaces of both encoders facing the detection unit. is there.
Further, the arithmetic unit has a function of obtaining a relative displacement between the stationary member and the rotating member based on a phase difference existing between output signals of the sensors.
The above configuration is the same as that of the state quantity measuring device of the rotary support device according to the above-described invention.

In particular, the state quantity measuring device for a rotation support device according to the present invention is characterized in that at least one of the both stationary side tracks and the both rotation side tracks is a stationary member or a rotating member provided with the track on its peripheral surface. It is provided by fitting an annular race ring member (outer ring or inner ring) to a mating member which is a member.
The axial end of the cylindrical spacer is abutted against the axial end of the bearing ring member, and the other axial end of the spacer is fixed to the mating member or fitted to the mating member. It is abutted against another bearing ring member.
And, by making the linear expansion coefficient of the material constituting the spacer different from the linear expansion coefficient of the material constituting the mating member, the both stationary side orbits and the both rotating side orbits accompanying the temperature change The change in the preload of each rolling element installed during the period is suppressed.
Further, the detected surfaces of the pair of encoders are each one of the following (1) and (2).
(1) A detected surface in which the phase of the characteristic change of the detected surface does not change with respect to the width direction of the detected surface (the structure described in FIGS. 6 to 13 described above).
(2) There are first and second characteristic change portions in which at least one detection portion of the sensor is opposed to each other in the width direction half of the detected surface in the use state. The detected surface in which the phase of the characteristic change of at least one of the characteristic changing portions is gradually changed in a state different from the other characteristic changing portion with respect to the width direction of the detected surface (structure shown in FIG. 15 described above).

When the above-described state quantity measuring device of the rotary support device of the present invention is implemented, the stationary member is a shaft member made of an iron-based alloy such as carbon steel or stainless steel as in the invention described in claim 2. And Then, a pair of inner ring raceways, each of which is a stationary side raceway, is provided on the outer peripheral surface of the shaft member directly or via an inner ring in a state where axial displacement relative to the shaft member is prevented.
The rotating member is a hub made of a light alloy such as an aluminum alloy or a magnesium alloy. A pair of outer ring raceways, each of which is a rotation side raceway, is formed on the inner peripheral surface of a pair of outer rings fitted inside the hub. In other words, a pair of outer rings, each having an outer ring raceway formed on each inner peripheral surface, are fitted and supported on the hub.
Further, the spacer is arranged in a direction in which the interval between the outer rings is increased with thermal expansion.

When carrying out the invention described in claim 2, for example, as in the invention described in claim 3, first and second spacers made of metal materials having different linear expansion coefficients from each other, They are arranged in series with respect to the axial direction.
When carrying out the invention described in claim 3, for example, as in the invention described in claim 4, the first spacer is made of an iron-based alloy such as carbon steel or stainless steel, and The second spacer is made of a light alloy such as an aluminum alloy or a magnesium alloy.

Preferably, when the present invention as described above is implemented, the y-axis of the three-dimensional orthogonal coordinate system composed of the x-axis, y-axis, and z-axis orthogonal to each other is stationary as in the invention described in claim 5. When matched with the central axis of the member, the calculator calculates the displacement x in the x-axis direction of the rotating member relative to the stationary member based on the phase difference existing between the output signals of the sensors, and y It has a function of calculating at least one displacement or inclination among the displacement y in the axial direction, the displacement z in the z-axis direction, the inclination φ _x around the x axis, and the inclination φ _z around the z axis.

Further, when the present invention as described above is implemented, for example, as in the invention described in claim 6 , the detected surfaces of the pair of encoders are each in the shape of a ring, and the detection portions of the sensors are set to both of them. Opposite the surface to be detected in the axial direction.
Alternatively, as in the seventh aspect of the present invention, the detected surfaces of the pair of encoders are cylindrical, and the detection portions of the sensors are opposed to the detected surfaces in the radial direction.

Further, when implementing the present invention as described above, for example, as in the invention described in claim 8 , based on the displacement or inclination of the rotating member relative to the stationary member calculated by the computing unit, A function of calculating an external force acting between the stationary member and the rotating member is provided.
Furthermore, when carrying out the present invention as described above, for example, as in the invention described in claim 9 , the rotation support device is a rotation support device for supporting a wheel of a motorcycle. The stationary member is a member such as a shaft member that is supported and fixed to the motorcycle body in use, and the rotating member is a member that supports and fixes the wheel, such as a wheel hub, or a part of the wheel. It is set as the member which comprises.

  According to the state quantity measuring device of the rotational support device of the present invention configured as described above, like a rotational support device for a wheel of a motorcycle, a stationary member that is rotatably supported by a double row rolling bearing device. Even when the material of the rotating member and the material of the rotating member are different from each other, the change in the preload applied to each rolling element constituting the double row rolling bearing device can be suppressed regardless of the temperature change. And the external force which acts between the stationary member and rotation member which comprise the said rotation support apparatus can be measured with a sufficient precision.

That is, in the case of both the state measuring devices of the rotation support device of the present invention, between the one end surface in the axial direction of the race ring member and a portion fixed to the counterpart member or another race ring member fitted to this counterpart member. A cylindrical spacer is arranged in Since the linear expansion coefficient of the material constituting the spacer is different from the linear expansion coefficient of the material constituting the mating member, an axial interval between a pair of raceway surfaces provided on the peripheral surface of the mating member accompanying a temperature change ( The change amount of the pitch is determined not by the expansion / contraction amount of the mating member but by the expansion / contraction amount of the spacer. Therefore, the material of the spacer is properly regulated, and the change in the axial interval (pitch) between the both raceway surfaces due to the temperature change is the difference in diameter between the stationary side track and the rotary side track due to this temperature change. If it regulates appropriately in relation to the change of the above, it is possible to suppress the change in the preload of each of the rolling elements installed between these two tracks. For example, according to the specific examples of the invention described in claims 2 to 4, this change in the preload can be sufficiently suppressed.

Further, if the configuration as in the invention described in claim 5 is adopted, the rotation of the small-diameter rotation is unavoidable because the detected surface of the encoder to be assembled must be small like the rotation support device for a wheel of a motorcycle. Even when applied to the support device, it is possible to accurately measure the external force acting between the stationary member and the rotation member constituting the rotation support device.
That is, in the case of the present invention, as in the case of the previous invention described above, when the rotating member is displaced relative to the stationary member (a pair of encoders are displaced in different states), along with this, The phase difference between the output signals of a plurality of sensors in which the detection units are opposed to the detection surfaces of both encoders changes. For this reason, based on this phase difference, the displacement and inclination of the rotating member relative to the stationary member can be calculated. In addition, the displacement and inclination of the rotating member with respect to the stationary member are reflected in the displacement of a pair of encoders arranged at a distance from each other. For this reason, an increase in the deterioration rate of the displacement and inclination calculation accuracy with respect to the detection error of each phase difference, which occurs as the diameters of the detected surfaces of both encoders become smaller, can be sufficiently suppressed. Therefore, even when applied to a rotation support device, such as a rotation support device for a motorcycle wheel, the outer diameter is relatively small, and the diameter of the detected surface of the encoder to be assembled must be relatively small. Based on each phase difference, the displacement and inclination of the rotating member relative to the stationary member can be calculated with high accuracy.

1 to 3 show an example of an embodiment of the present invention. In this example, it is assumed that the following structures (a) to (e) are adopted.
(a) The stationary member that does not rotate even when in use is a shaft member 3a that is supported by the lower ends of the front forks 2 and 2 that are part of the body of the motorcycle, and is made of an iron-based alloy.
(b) The rotating members that rotate when in use are aluminum alloy hubs 4a provided at the center of the front wheel of the motorcycle, each of which is a single-row deep groove type (or an angular type). A pair of rolling bearings 5 and 5 are rotatably supported around the shaft member 3a.
(c) A preload is applied to the balls 8 and 8 constituting the rolling bearings 5 and 5 together with the contact angle of the rear combination type.
(d) The pair of inner rings 6 and 6 constituting the both rolling bearings 5 and 5 are positioned in two axial positions on the outer peripheral surface of the shaft member 3a in the axial direction with respect to the shaft member 3a. The outer fitting is fixed while the displacement is prevented.
(e) The first and second outer ring spacers 29, 30 are provided between the pair of outer rings 7a, 7b constituting the both rolling bearings 5, 5, and the linear expansion of these outer ring spacers 29, 30 is provided. The linear expansion coefficient of the iron-based alloy constituting the shaft member 3a (and, if necessary, the linear expansion coefficient of the aluminum-based alloy constituting the hub 4a) and the double rolling bearings 5 and 5 are constituted. The inner rings 6 and 6 and the outer rings 7a and 7b are appropriately regulated in relation to other specifications including the allowance for the bearing material 3a and the hub 4a .
The structure of this example is applied to each of the balls 8 and 8 constituting the both rolling bearings 5 and 5 regardless of the temperature change by adopting the structures of the above (a) to (e). I try to suppress changes in preload.

Hereinafter, the structure of this example will be specifically described.
The shaft member 3a is formed by fitting and fixing an inner cylinder 31 and an outer cylinder 32 each made of an iron-based alloy. The inner rings 6 and 6 are fixedly fitted on the outer peripheral surface of the outer cylinder 32 near the both ends in the axial direction by interference fitting while preventing axial displacement with respect to the shaft member 3a. . For this purpose, the inner end surfaces in the axial direction (end surfaces near the center in the axial direction) of the inner rings 6 and 6 are brought into contact with the outward step surfaces 33 and 33 formed on the outer peripheral surface of the outer cylinder 32 near the both ends in the axial direction. At the same time, the outer end surfaces in the axial direction of the inner rings 6 and 6 (end surfaces near both ends in the axial direction) are held down by the inner end surfaces in the axial direction of the holding rings 10a and 10b, respectively. Of these holding rings 10 a and 10 b, the outer end surface in the axial direction of one (left side in FIG. 1) of the holding ring 10 a abuts against the inner surface of the lower end of the front fork 2. Further, the outer surface of the lower end portion of the front fork 2 is held down by a head portion 36 of a bolt 35 screwed to one end portion in the axial direction of the inner cylinder 31 (left end portion in FIG. 1). On the other hand, the axially outer end surface of the other (right side in FIG. 1) holding ring 10 b is another stepped surface 34 formed in a part of the inner cylinder 31 protruding from the outer cylinder 32. It has hit against. With this configuration, as in (d), the inner rings 6 and 6 are prevented from being displaced in the axial direction with respect to the shaft member 3a at two positions in the axial direction of the outer peripheral surface of the shaft member 3a. It is fixed in the state. The state quantity measuring sensors 19A and 19B are installed in a part of the outer cylinder 32 through a sensor case 39, and the output signals of these sensors 19A and 19B are taken out from the one holding ring 10a. The outside is taken out through the hole 37. However, since this part is not related to the features of the present invention, such as being able to be configured in the same manner as the previous invention described above, detailed description thereof is omitted.

  The hub 4a is made of an aluminum-based alloy, and a ridge portion 38 projecting radially inward is formed over the entire circumference at a portion near one end of the intermediate portion of the inner peripheral surface (leftward in FIG. 1). ing. Then, of the outer rings 7a and 7b constituting the rolling bearings 5 and 5, the inner end surface in the axial direction of one (left side in FIG. 1) of the outer ring 7a is abutted against one side surface of the protruding portion 38 in the axial direction. ing. On the other hand, the other outer ring 7b (on the right side in FIG. 1) is fitted into the portion near the other end (right side in FIG. 1) of the inner peripheral surface of the hub 4a by a light interference fit or gap fit. . Accordingly, the other outer ring 7b is displaced in the axial direction with respect to the hub 4a when a strong force is applied at least in the axial direction. Further, the first and second outer ring spacers 29, 30 are arranged in series with respect to the axial direction between the inner end surface in the axial direction of the other outer ring 7b and the other side surface in the axial direction of the protruding portion 38. Provided. These outer ring spacers 29, 30 are stretched between the other outer ring 7b and the protrusion 38. Accordingly, the distance between the other outer ring 7b and the protrusion 38, and the distance between the outer rings 7a and 7b, is regulated by the axial lengths of the outer ring spacers 29 and 30. One of the outer ring spacers 29, 30 (for example, the first outer ring spacer 29) is made of an iron-based alloy, and the other spacer (for example, the second outer ring spacer 30) is made of aluminum. Made of a base alloy.

  As described above, the inner rings 6 and 6 are fixed at the positions of the two outer peripheral surfaces of the shaft member 3a, and the outer rings 7a and 7b are positioned at the positions of the two inner peripheral surfaces of the hub 4a as described above. In the supported state, a preload is applied to each of the balls 8 and 8 together with a contact angle of the rear combination type. For this purpose, the sum of the axial dimensions of the protrusion 38 and the outer ring spacers 29, 30 is taken into consideration between the stepped surfaces 33, 33 while taking into account the contact angle to be applied and the size of the preload. Regulated in relation to the interval. Except for the use of a pair of outer ring spacers 29, 30 made of different materials, a general back combination type double row ball bearing is used for the basic design method when applying contact angle and preload. Since this is the same as the case of, detailed description is omitted.

The state quantity measuring device of the rotation support device of the present example configured as described above is a relative displacement between the shaft member 3a and the hub 4a in the same manner as the state quantity measurement device of the rotation support device according to the previous invention. And the direction and magnitude of the force (external force) acting between these members 3a and 4a can be obtained.
In particular, in the case of the state quantity measuring device of the rotation support device of this example, regardless of the difference in thermal expansion amount between the shaft member 3a made of iron alloy and the hub 4a made of aluminum alloy accompanying a temperature change. Therefore, the change in the preload applied to the balls 8 and 8 constituting the both rolling bearings 5 and 5 can be suppressed. And the external force which acts between the said both members 3a and 4a can be measured with a sufficient precision.

As described above, the reason why the change in the preload can be suppressed regardless of the temperature change will be described below with reference to FIGS.
First, a contact angle of the back combination type is provided, and the preload of the double row angular contact ball bearing provided between the outer peripheral surface of the iron-based alloy shaft member 3a and the inner peripheral surface of the aluminum-based alloy hub 4a is obtained. The situation that changes as the temperature rises will be described with reference to FIG.

Both the members 3a and 4a expand as the temperature rises. The expansion amount of each of the members 3a and 4a is greater than that of the hub 4a made of an aluminum alloy in both the radial direction and the axial direction. It becomes larger than 3a.
Due to the difference in the amount of expansion in the radial direction, the preload tends to decrease. That is, the distance between the outer peripheral surface of the shaft member 3a and the inner peripheral surface of the hub 4a is increased, and the outer diameters of the inner ring raceways 26 and 26 provided on the outer peripheral surfaces of the inner rings 6 and 6 are increased. The degree to which the inner diameters of the outer ring races 27, 27 formed on the inner peripheral surfaces of the outer rings 7a, 7b are increased is prominent, and the preload tends to decrease.
On the other hand, the preload tends to increase due to the difference in the expansion amount in the axial direction. That is, compared with the extent to which the distance between the inner rings 6 and 6 is increased, the degree to which the distance between the outer rings 7a and 7b is increased, and the preload tends to increase.

  However, as described above, the degree to which the preload increases due to the difference in the amount of expansion in the axial direction becomes more significant than the degree to which the preload decreases due to the difference in the amount of expansion in the radial direction. For this reason, as it is, the increase in the preload due to the temperature rise cannot be completely offset by the decrease, and the preload applied to the balls 8 and 8 constituting the rolling bearings 5 and 5 increases when the temperature rises. To do. As a result, the measurement accuracy of the external force acting between the members 3a and 4a is deteriorated. In short, an inner ring spacer made of an iron-based alloy (the same applies to a part of the shaft member 3a made of an iron-based alloy) is provided between the inner rings 6 and 6, and an aluminum-based alloy is formed between the outer rings 7a and 7b. If the outer ring spacer made of aluminum (same for a part of the hub 4a made of aluminum alloy) is simply clamped, as shown in FIG. The difference ΔL in the amount of expansion between the seats becomes excessive. The increase in the preload based on the difference ΔL in the expansion amount cannot be completely offset by the decrease in the preload based on the difference in the expansion amount in the radial direction, and the preload increases as described above. 3A and 3B show the total length and thermal expansion of both spacers when the temperature of the outer ring spacer and the inner ring spacer increases from 20 ° C to 80 ° C. Yes.

  On the other hand, in the case of this example, between the outer rings 7a, 7b, a first outer ring spacer 29 made of an iron alloy and a second outer ring spacer 30 made of an aluminum alloy, Since they are arranged in series with respect to the axial direction, which is the direction of thermal expansion, as shown in FIG. 3B, the outer ring spacers 29, 30 and the inner ring spacers at the time of temperature rise. The difference in expansion amount δL can be kept small. For this reason, the increase in the preload based on the difference in expansion amount δL can be almost offset by the decrease in the preload based on the difference in the expansion amount in the radial direction, and the change in the preload can be suppressed even when the temperature rises. . As a result, the external force acting between the members 3a and 4a can be accurately measured regardless of the temperature change. The magnitude of the difference δL can be arbitrarily adjusted by changing the ratio of the lengths of the spacers 29 and 30.

  In the case of this example, first and second outer ring spacers 29, 30 made of different materials are disposed between the outer rings 7a, 7b. The reason for this is to avoid an increase in cost and lack of rigidity due to the use of a special alloy spacer. However, when carrying out the present invention, it is not always necessary to arrange a plurality of outer ring spacers between the outer rings 7a and 7b. As shown in FIG. 3B, a metal material such as an alloy capable of realizing a difference in thermal expansion δL from the inner ring spacer is used, and the change in the preload can be suppressed by a single outer ring spacer. it can.

  The present invention is not limited to a rotation support device for a wheel of a motorcycle, and can be applied to various rotation support devices having two rows of rolling bearing portions. For example, the present invention can be applied to a rotation support device that rotatably supports a spindle shaft for a machine tool inside a housing. In a machine tool, the dimensional change of each component due to thermal expansion affects the processing accuracy, and the pressing force against the workpiece also affects the processing accuracy. Therefore, high-precision machining can be realized by measuring the displacement and inclination of the spindle shaft and the external force acting on the spindle shaft and feeding back these measured values to the controller of the machine tool.

Sectional drawing which shows one example of embodiment of this invention. The schematic diagram for demonstrating the state of the thermal expansion of each member connected with a preload change at the time of a temperature rise. The figure for demonstrating the difference of the thermal expansion amount of an outer ring spacer and an inner ring spacer. 1 is a schematic cross-sectional view showing a first example of an embodiment of the prior invention in a state assembled to a motorcycle. Similarly sectional drawing. The projection figure which looked at a pair of encoder main body and each sensor from the same side regarding the axial direction. The figure similar to FIG. 6 which shows the 2nd example of embodiment of prior invention. The figure similar to FIG. 6 which shows the 3rd example. The figure similar to FIG. 6 which shows the 4th example. The figure similar to FIG. 6 which shows the said 5th example. The figure similar to FIG. 6 which shows the 6th example. The figure similar to FIG. 6 which shows the 7th example. The figure similar to FIG. 6 which shows the 8th example. The figure similar to FIG. 5 which shows the 9th example. The perspective view which shows another example of the combination of an encoder and a sensor which can be used when implementing prior invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wheel 2 Front fork 3, 3a Shaft member 4, 4a Hub 5 Rolling bearing 6 Inner ring 7, 7a, 7b Outer ring 8 Ball 9 Spacer 10, 10a, 10b Retaining ring 11 Step surface 12 Seal ring 13, 13a Encoder 14 Core metal 15 encoder main body 16 cylindrical portion 17 cylindrical portion 18 circular ring portion _{19A, 19A 1 ~19A 6, 19B} , 19B 1 ~19B 3 sensor 20 support member 21 operator 22 groove 23 holes 24 first characteristic change portion 25 second Characteristic changing portion 26 Inner ring raceway 27 Outer ring raceway 29 First outer ring spacer 30 Second outer ring spacer 31 Inner cylinder 32 Outer cylinder 33 Stepped surface 34 Stepped surface 35 Bolt 36 Head 37 Extraction hole 38 Projection portion 39 Sensor case

Claims (9)

A rotation support device and a state quantity measurement device;
Among these, the rotation support device is provided with a pair of stationary side tracks on the stationary side circumferential surface, a stationary member that does not rotate even when in use, and a pair of rotation side tracks on the rotating side circumferential surface, which rotates when in use. A plurality of members, and a plurality of rolling elements provided between the rotating side tracks and the stationary side tracks, each provided in a freely rotatable manner,
The state quantity measuring device includes a pair of encoders that are supported at two axially separated positions of the rotating member and that rotate together with the rotating member, and a sensor device that is supported and fixed to a portion that does not rotate during use. And a computing unit,
Each of the pair of encoders has a detected surface concentric with the rotating member, and the characteristics of both the detected surfaces are changed alternately and at the same pitch in the circumferential direction , The detected surfaces of the encoders are respectively detected on the detected surface where the phase of the characteristic change of the detected surface does not change with respect to the width direction of the detected surface and on both halves of the detected surface in the width direction. The sensor has at least one first and second characteristic changing portions opposed to each other in the use state, and the phase of the characteristic change of at least one of the two characteristic changing portions With respect to the width direction of the detection surface, it is either one of the detected surface gradually changing in a state different from the other characteristic change portion,
The sensor device includes one or more sensors having a detection unit opposed to a detection surface of one of the encoders, and one or more sensors having a detection unit opposed to a detection surface of the other encoder. Each of these sensors, each of these sensors is to change the output signal corresponding to the characteristic change of the portion of the detection surface of both encoders facing the detection unit,
The arithmetic unit has a function of obtaining a relative displacement between the stationary member and the rotating member based on a phase difference existing between output signals of the sensors. Because
At least one of the both stationary-side tracks and the both rotating-side tracks is fitted with an annular race ring member on a mating member that is a stationary member or a rotating member provided on the peripheral surface of the track. It was established by doing
One end surface in the axial direction of the cylindrical spacer is abutted against one end surface in the axial direction of the bearing ring member, and the other end surface in the axial direction of the spacer is fitted to a portion fixed to the mating member or the mating member Against another bearing ring member,
By making the coefficient of linear expansion of the material constituting the spacer different from the coefficient of linear expansion of the material constituting the mating member, the space between the stationary side track and the rotational side track due to temperature change is different. An apparatus for measuring the amount of state of a rotary support device that suppresses a change in the preload of each of the rolling elements installed in the above. The stationary member is a shaft member made of an iron-based alloy, and a pair of inner ring raceways, each of which is a stationary side raceway, are provided on the outer peripheral surface of the shaft member in a state in which axial displacement relative to the shaft member is prevented. And
The rotating member is a hub made of a light alloy, and a pair of outer ring raceways, each of which is a rotation side raceway, are formed on the inner peripheral surfaces of a pair of outer rings fitted into the hub,
The spacer is arranged in a direction to increase the interval between these outer rings with thermal expansion.
The state quantity measuring device of the rotation support device according to claim 1.   The state quantity measuring device for a rotary support device according to claim 2, wherein first and second spacers made of metal materials having different linear expansion coefficients are arranged in series in the axial direction.   The state quantity measuring device for a rotary support device according to claim 3, wherein the first spacer is made of an iron-based alloy and the second spacer is made of a light alloy. When the y-axis of the three-dimensional orthogonal coordinate system consisting of the x-axis, y-axis, and z-axis orthogonal to each other matches the central axis of the stationary member, the arithmetic unit exists between the output signals of the sensors. Based on the phase difference, the rotation member x with respect to the stationary member in the x-axis direction displacement x, the y-axis direction displacement y, the z-axis direction displacement z, the inclination φ _x about the x-axis, and the z-axis of the surrounding slope phi _z, and has a function of calculating at least one displacement or inclination,
The state quantity measuring device of the rotation support device according to any one of claims 1 to 4. A pair of the detected face is a circle ring each encoder, the detection unit of the sensor is opposed in the axial direction with respect to the both the sensed surface, according to any one of claims 1 to 5 State quantity measuring device for the rotating support device. A sensed surface of a pair of encoders each cylinder, detecting portions of the sensors is opposed in the radial direction with respect to the both the sensed surface, according to any one of claims 1 to 5 State quantity measuring device for the rotating support device. Calculator, based on the displacement or inclination of the rotary member relative to the stationary member that it has calculated, has a function of calculating the external force acting between these stationary member rotating member, any one of the preceding claims 1. A state quantity measuring device for a rotary support device according to item 1. The rotation support device is a rotation support device for a wheel of a motorcycle, and in use, the stationary member becomes a member that is supported and fixed to the motorcycle body, and the rotation member supports or fixes the wheel or one of the wheels. The state quantity measuring device of the rotation support device according to any one of claims 1 to 8 , which is a member constituting the part.

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