JP2007205392A - Wheel supporting rolling bearing unit with load measuring device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving wheel rolling bearing unit for actualizing technology allowing a bearing maker to understand the relationship between the size of a load applied between an outer ring 1 and a hub 11b constituting the unit and a detection signal from each of sensors 16c, 16d. <P>SOLUTION: In a memory of a computing element which finds the load in accordance with the detection signal from each of the sensors 16c, 16d, data is recorded which shows the relationship between the detection signal and the load. When finding the data, an inner ring 24 as part of the hub 11b is thrust against a hub body 23 outward to the axial direction to impart to each of rolling elements 8, 8 preload having the same size as preload imparted thereto in use. In this condition, the hub 11b is rotated while imparting known loads having different sizes between the outer ring 1 and the hub 11b. The detection signal from each of the sensors 16c, 16d is measured to find the relationship between the detection signal and the load. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The wheel bearing rolling bearing unit with a load measuring device that is an object of the present invention is used to obtain a load applied between an outer ring and a hub that are combined in a relatively rotatable manner via a plurality of rolling elements. Further, the obtained load is used for ensuring the running stability of a vehicle such as an automobile.

  For example, automobile wheels are rotatably supported by a suspension device by a double row angular type wheel support rolling bearing unit. In order to ensure the running stability of the automobile, for example, as described in Non-Patent Document 1, an antilock brake system (ABS), a traction control system (TCS), and an electronically controlled vehicle stability A vehicle travel stabilization device such as a control system (ESC) is used. In order to control such various vehicle running stabilization devices, signals such as the rotational speed of the wheels and the acceleration in each direction applied to the vehicle body are required. In order to perform higher-level control, it may be preferable to know the magnitude of a load (for example, one or both of a radial load and an axial load) applied to the rolling bearing unit via a wheel.

In view of such circumstances, Patent Document 1 discloses a radial applied to a rolling bearing unit based on the revolution speed of a pair of balls constituting a rolling bearing unit which is a double-row angular ball bearing unit. An invention relating to a rolling bearing unit for supporting a wheel with a load measuring device for measuring a load or an axial load is described.
FIG. 8 shows a first example of a wheel bearing rolling bearing unit with a load measuring device described in Patent Document 1. In the case of this conventional structure, the sensor unit 4 is inserted into the mounting hole 3 formed in the portion between the double-row angular outer ring raceways 2 and 2 at the intermediate portion in the axial direction of the outer ring 1, and the tip 5 of the sensor unit 4 is inserted. Projecting from the inner peripheral surface of the outer ring 1. The tip portion 5 is provided with a pair of revolution speed detection sensors 6 a and 6 b and a single rotation speed detection sensor 7.

  And the detection part of each revolution speed detection sensor 6a, 6b of these is provided in each holder 9a, 9b holding each rolling element 8a, 8b arranged in a double row freely, and detecting revolution speed The revolving speed of each of the rolling elements 8a and 8b can be detected by being close to and opposed to the side surface in the axial direction that is the detection surface of the encoders 10a and 10b. Further, the rotational speed of the hub 11 is set so that the detection portion of the rotational speed detection sensor 7 is closely opposed to the outer peripheral surface, which is the detected surface of the rotational speed detection encoder 12 fitted and fixed to the intermediate portion of the hub 11. Can be detected freely. According to the wheel support rolling bearing unit with a load measuring device having such a configuration, the load (radial load and axial load) applied between the outer ring 1 and the hub 11 regardless of the fluctuation of the rotational speed of the hub 11. Load).

That is, in the case of the wheel support rolling bearing unit with a load measuring device as described above, an arithmetic unit (not shown) is used to detect the outer ring 1 and the hub 11 based on the detection signals sent from the sensors 6a, 6b and 7. One or both of a radial load and an axial load applied between the two are calculated. For example, when the radial load is obtained, the computing unit obtains the sum of the revolution speeds of the rolling elements 8a and 8b in the rows detected by the revolution speed detection sensors 6a and 6b, and the sum and the rotation speed. The radial load is calculated based on a ratio with the rotational speed of the hub 11 detected by the speed detection sensor 7. The axial load is obtained by calculating a difference between the revolution speeds of the rolling elements 8a and 8b in each row detected by the revolution speed detection sensors 6a and 6b, and the difference between the difference and the rotational speed detection sensor 7 is detected. It calculates based on ratio with the rotational speed of the said hub 11 to do. Or the said axial load is calculated | required also by ratio of the revolution speed of the rolling elements 8a and 8b of each said row | line | column. This point will be described with reference to FIG. In the following description, the contact angles α _a and α _b of the rolling elements 8a and 8b in each row in the state where the axial load Fy is not applied are the same.

FIG. 9 schematically shows the rolling bearing unit for supporting the wheel shown in FIG. 8 and shows the action state of the load. Preloads F ₀ and F ₀ are applied to the rolling elements 8 a and 8 b arranged in a double row between the double row angular type inner ring raceways 13 and 13 and the double row angular type outer ring raceways 2 and 2. Further, a radial load Fz is applied to the rolling bearing unit during use due to the mass of the vehicle body or the like. Further, an axial load Fy is applied due to centrifugal force applied during turning. These preloads F ₀ , F ₀ , radial load Fz, and axial load Fy all affect the contact angles α (α _a , α _b ) of the rolling elements 8a, 8b. Then, the contact angle alpha _a, the alpha _b is changed, respective rolling elements 8a, the revolution speed n _c and 8b changes. The diameter of the pitch circle of each of the rolling elements 8a, 8b is D, the diameter of each of the rolling elements 8a, 8b is d, the rotational speed of the hub 11 provided with the inner ring raceways 13, 13 is n _i , When the rotational speed of the outer race 1 provided with the outer ring raceway 2,2 to n _o, the revolution speed n _c is expressed by the following equation (1).
n _c = {1− (d · cos α / D) · (n _i / 2)} + {1+ (d · cos α / D) · (n _o / 2)} (1)

As is clear from this equation (1), the rolling elements 8a, the revolution speed n _c and 8b, these rolling elements 8a, the contact angle α (α _a, α _b) of 8b varies in response to changes in As described above, the contact angles α _a and α _b change according to the radial load Fz and the axial load Fy. Thus the revolution speed n _c is changed according to these radial load Fz and the axial load Fy. In the case of the structure shown in FIGS. 8 to 9, since the hub 11 rotates and the outer ring 1 does not rotate, specifically, as the radial load Fz increases as shown in FIG. The speed nc _decreases . Further, with respect to the axial load Fy, as shown in FIG. 11, the revolution speed of the row supporting the axial load Fy is increased, and the revolution speed of the row not supporting the axial load Fy is decreased. Therefore, on the basis of the revolution speed n _c, it will be asked to the radial load Fz and the axial load Fy.

In FIG. 10, the solid line A relates to the rolling elements 8b and 8b on the side where the radial load Fz is supported, and the broken line B similarly relates to the rolling elements 8a and 8a on the side where the radial load Fz is supported. The relationship between each revolution speed (and the ratio of the rotation speed of the hub 11) and the radial load Fz is shown. In FIG. 11, the broken line C indicates the relationship between the axial load Fy and the revolution speed of the rolling elements 8a and 8a in the row that supports the axial load Fy, and the solid line D indicates the axial load Fy and the axial load. The relationship with the revolution speed of the rolling elements 8b and 8b of the row | line | column which does not support Fy is shown, respectively. As is apparent from such 10-11, rolling elements 8a of each row, based on the revolution speed n _c of 8b, asked to the radial load Fz and the axial load Fy.

There are various other methods for calculating one or both of the radial load Fz and the axial load Fy based on the signals of the revolution speed detection sensors 6a and 6b. Since this method is described in detail in the above-mentioned Patent Document 1, detailed description thereof is omitted.
The structure shown in FIG. 8 is a structure in which the revolution speed detection sensors 6a and 6b and the rotational speed detection sensor 7 are held at the tip 5 of a single sensor unit 4. Each sensor 6a, 6b, 7 may be installed separately. Further, for example, as in the second example of the conventional structure of the wheel bearing rolling bearing unit with a load measuring device shown in FIG. 12, a pair of revolution speed detecting sensors 6a and 6b is connected to the tip of the sensor unit 4a. The rotational speed detection sensor 7a may be held by the cover 14 fitted and fixed to the inner end portion of the outer ring 1. In this case, the rotational speed detecting encoder 12 a is fitted and fixed to the inner end portion of the hub 11.

  Although not disclosed yet, Japanese Patent Application No. 2005-147642 measures the magnitude of the load applied to the rolling bearing unit based on the phase difference between the output signals of a pair of sensors arranged in the direction of the load. The invention is disclosed. 13 to 20 show the structures of four examples according to the prior invention selected from the prior inventions disclosed in the above application. Among these structures according to the prior inventions, the structures of the first and second examples shown in FIGS. 13 to 17 are all the inner diameter of the outer ring 1 that does not rotate while being supported by the suspension device as shown in FIG. On the side, a hub 11 that rotates together with the wheel in a state where the wheel is supported and fixed (coupled and fixed) is rotatably supported via a plurality of rolling elements 8 and 8. The encoders 15 and 15a are externally fitted and fixed to the intermediate part of the hub 11, and the sensors 16 and 16a are provided between the rolling elements 8 and 8 arranged in a double row at the axially intermediate part of the outer ring 1. Each pair is provided in a state where the respective detection units are close to and opposed to the outer peripheral surfaces of the encoders 15 and 15a, which are detected surfaces. Note that a magnetic detection element such as a Hall IC, a Hall element, an MR element, or a GMR element is incorporated in the detection portion of the sensors 16 and 16a.

  In the case of the structure of the first example of the prior invention, the encoder 15 is made of a permanent magnet. On the outer peripheral surface of the encoder 15, which is the detection surface, portions magnetized in the N pole and portions magnetized in the S pole are arranged alternately at equal intervals in the circumferential direction. The boundary between the portion magnetized in the N pole and the portion magnetized in the S pole is inclined by the same angle with respect to the axial direction of the encoder 15, and the inclination direction with respect to the axial direction of the encoder 15 is changed. The axial directions are opposite to each other at the intermediate portion. Therefore, the portion magnetized in the N pole and the portion magnetized in the S pole have a “<” shape with the axially middle portion protruding (or recessed) most in the circumferential direction.

  Further, the position where the detection parts of both the sensors 16 and 16 face the outer peripheral surface of the encoder 15 is the same position in the circumferential direction of the encoder 15. In other words, the detection units of both the sensors 16 and 16 are arranged on the same virtual plane including the central axis of the outer ring 1. Further, in the state where no axial load is applied between the outer ring 1 and the hub 11, the axial direction intermediate portion between the portion magnetized in the N pole and the portion magnetized in the S pole is related to the circumferential direction. The installation position of each member 15, 16, 16 is regulated so that the most protruding part (the part where the inclination direction of the boundary changes) is just at the center position between the detection parts of both sensors 16, 16. is doing. In the case of the first example of the present invention, since the encoder 15 is made of a permanent magnet, it is not necessary to incorporate a permanent magnet on both the sensors 16 and 16 side.

  In the case of the first example of the prior invention configured as described above, when an axial load is applied between the outer ring 1 and the hub 11, the phase at which the output signals of the sensors 16 and 16 change is shifted. That is, in the neutral state where an axial load is not applied between the outer ring 1 and the hub 11 and the outer ring 1 and the hub 11 are not relatively displaced, the detection units of the sensors 16 and 16 are It is opposed to the solid lines a and b in FIG. 16A, that is, the portion shifted from the most protruding portion by the same amount in the axial direction. Therefore, the phases of the output signals of the sensors 16 and 16 coincide as shown in FIG.

  On the other hand, when a downward axial load acts on the hub 11 to which the encoder 15 is fixed in FIG. 16A (the outer ring 1 and the hub 11 are relatively displaced in the axial direction), The detection parts of both sensors 16 and 16 are opposed to the broken lines B and B in FIG. 16A, that is, the parts different in axial displacement from the most protruding part. In this state, the phases of the output signals of the sensors 16 and 16 are shifted as shown in FIG. Further, when an upward axial load is applied to the hub 11 to which the encoder 15 is fixed as shown in FIG. 16A, the detecting portions of both the sensors 16 and 16 are connected to the chain line hub shown in FIG. , C, that is, the deviation in the axial direction from the most projecting portion opposes different portions in the opposite direction. In this state, the phases of the output signals of the sensors 16 and 16 are shifted as shown in FIG.

  As described above, in the case of the first example of the prior invention, the phases of the output signals of the sensors 16 and 16 are shifted in a direction corresponding to the acting direction of the axial load applied between the outer ring 1 and the hub 11. . Further, the degree of displacement (displacement amount) of the output signals of the sensors 16 and 16 due to the axial load increases as the axial load increases. Therefore, in the case of the first example, the presence or absence of a phase shift between the output signals of both the sensors 16 and 16 and, if there is a shift, between the outer ring 1 and the hub 11 based on the direction and magnitude. The direction and magnitude of the acting axial load can be determined.

  On the other hand, in the case of the structure of the second example of the previous invention, as described above, an encoder 15a made of a magnetic metal plate as shown in FIG. Slit-like through holes 17a and 17b and column portions 18a and 18b are alternately arranged at equal intervals in the circumferential direction on the outer peripheral surface of the encoder 15a, which is a detection surface. The through holes 17a and 17b and the column portions 18a and 18b are inclined by the same angle with respect to the axial direction of the encoder 15a, and the inclined direction with respect to the axial direction is bounded by the intermediate portion in the axial direction of the encoder 15a. Are in opposite directions. That is, the encoder 15a is formed with through holes 17a, 17a inclined in the same direction in the predetermined direction with respect to the axial direction in one half of the axial direction, and in the opposite direction to the predetermined direction in the other half of the axial direction. Through holes 17b and 17b inclined by the same angle are formed.

  On the other hand, the pair of sensors 16a and 16a are installed in the portion between the rolling elements 8 and 8 arranged in a double row at the axially intermediate portion of the outer ring 1, and the detection parts of both the sensors 16a and 16a are arranged as follows. The encoder 15a is placed in close proximity to the outer peripheral surface. The positions where the detection parts of both the sensors 16a and 16a face the outer peripheral surface of the encoder 15a are the same in the circumferential direction of the encoder 15a. In addition, a rim portion 19 that is located between the through holes 17a and 17b and continues to the entire circumference in a state in which an axial load does not act between the outer ring 1 and the hub 11 includes both the sensors 16a and 16a. The installation positions of the members 15a, 16a, and 16a are restricted so that they are located at the center position between the detection units. In the case of the second example of the present invention, since the encoder 15a is simply made of a magnetic material, it is necessary to incorporate permanent magnets on the two sensors 16a and 16a sides.

In the case of the second example of the prior invention configured as described above, when an axial load acts between the outer ring 1 and the hub 11 (the outer ring 1 and the hub 11 are relatively displaced in the axial direction), the above-described prior invention. As in the case of the first example, the phase in which the output signals of the sensors 16a and 16a change is shifted. Accordingly, in the case of the second example of the prior invention, as in the case of the first example of the previous invention, the presence / absence of the phase shift of the output signals of the sensors 16a and 16a, and the direction of the shift, if any. Further, based on the size and the magnitude, the acting direction and magnitude of the axial load acting between the outer ring 1 and the hub 11 can be obtained.
If the encoder is configured in an annular shape, the side surface in the axial direction of the encoder is a detection surface, and the detection portions of the pair of sensors are opposed to the detection surface in a state shifted in the radial direction, the above It is also possible to determine the displacement in the radial direction between the outer ring 1 and the hub 11 and thus the radial load applied between the outer ring 1 and the hub 11.

  18 to 19 show a structure for obtaining a displacement in the axial direction applied between the outer ring 1a and the hub 11a by a single sensor as a third example of the prior invention. In the case of the third example of the present invention, a tapered roller is used as the rolling elements 8c and 8c because it is intended for a wheel bearing rolling bearing unit for supporting a driving wheel of a heavy automobile. Further, a spline hole 20 is formed at the center of the hub 11a for inserting a spline shaft attached to the constant velocity joint. An annular encoder 15b made of a magnetic metal material is fitted and fixed to an intermediate portion of the hub 11a. On the outer peripheral surface of the encoder 15b, the concave portions 21 and 21 and the convex portions 22 and 22 are alternately arranged in the circumferential direction. The width dimension in the circumferential direction of each of the concave portions 21 and 21 and the convex portions 22 and 22 gradually changes in the axial direction.

  On the other hand, a magnetic detection type sensor 16b is inserted into the mounting hole 3a formed in the intermediate part of the outer ring 1a, and the detection part provided at the tip part of the sensor 16b is the outer periphery of the encoder 15b which is a detected surface. It is in close proximity to the surface. The detection signal of the sensor 16b changes as the concave portions 21 and 21 and the convex portions 22 and 22 pass alternately in the vicinity of the detection portion. And after making it a rectangular wave by the attached waveform shaping circuit, it sends out to the calculator which is not shown in figure. Thus, the change pattern of the detection signal of the sensor 16b sent from the waveform shaping circuit to the arithmetic unit (duty ratio of the detection signal = high potential duration / one cycle) is the encoder facing the detection unit. It changes with the axial direction position of the outer peripheral surface of 15b. Therefore, an axial load acting between the outer ring 1a and the hub 11a is obtained based on the change pattern.

  Next, FIG. 20 shows a fourth example of the structure according to the prior invention, in the radial direction between the outer ring 1, 1 a and the hub 11, 11 a (see FIGS. 8, 12, 13, 18) by a single sensor. The structure for obtaining the displacement is shown. The encoder 15c incorporated in this structure is formed in an annular shape by a magnetic metal plate, and the trapezoidal through-holes 17c and 17c, each of which has a larger width in the circumferential direction toward the outer side in the radial direction. Formed at intervals. The detection part of the sensor is brought close to and opposed to one side surface of the encoder 15c in the axial direction. In the case of the fourth example of the present invention configured to include such an encoder 15c, when the outer rings 1, 1a and the hubs 11, 11a are relatively displaced in the radial direction based on the radial load, the duty of the detection signal of the sensor is increased. The ratio (high potential duration / one cycle) changes. Therefore, based on the duty ratio, the direction and magnitude of the relative displacement, and further the magnitude of the radial load applied between the outer rings 1 and 1a and the hubs 11 and 11a are obtained.

  In any case, the load obtained by the wheel support rolling bearing unit with a load measuring device is commensurate with the load generated on the contact surface (ground contact surface) between the wheel (tire) and the road surface. Therefore, if the control for stabilizing the running state of the vehicle is performed based on the obtained load, the feed forward control for preventing the posture of the vehicle from becoming unstable becomes possible. Advanced control to ensure stability is possible.

  When a wheel support rolling bearing unit with a load measuring device as described above is implemented, the magnitude of the load applied to the wheel supporting rolling bearing unit and the outer ring and hub constituting the wheel supporting rolling bearing unit It is necessary that the relationship (zero point and gain) with the relative displacement is known. The relationship between the load and the relative displacement amount (rigidity of the wheel supporting rolling bearing unit) varies greatly depending on the preload value applied to each rolling element constituting the wheel supporting rolling bearing unit. Further, the preload value may be slightly different for each wheel supporting rolling bearing unit due to inevitable manufacturing errors.

  Accordingly, with respect to many products shipped from the manufacturer of the wheel bearing rolling bearing unit with load measuring device (hereinafter referred to as “bearing manufacturer”), the zero point and gain (or map) stored in the memory of the arithmetic unit are stored. If the same applies hereinafter), there is a possibility that accurate load measurement cannot be performed. In consideration of such circumstances, it is desirable to ship each product after obtaining the zero point and gain for each product. And the operation | work which calculates | requires this zero point and a gain needs to be performed in the state which gave the same preload as the time of use to each rolling element which comprises the wheel bearing rolling bearing unit. In the case of a rolling bearing unit for supporting a wheel for a driven wheel (front wheel of an FR vehicle, rear wheel of an FF vehicle), the preloading to each of these rolling elements is completed at the stage of the bearing manufacturer. It is easy to obtain the above zero and gain by the bearing manufacturer.

For example, in Patent Document 2, regarding the structure for measuring the load based on the fluctuation of the revolution speed described in Patent Document 1 as shown in FIGS. An invention for obtaining the relationship (zero point and gain) between the revolution speeds n _ca and n _{cb of} each rolling element and the radial load Fz or the axial load Fy is described. According to the invention described in Patent Document 2 as described above, even when the preload state is different for each rolling bearing unit, the load applied to each rolling bearing unit can be obtained with high accuracy. However, in order to implement the invention described in Patent Document 2, it is premised that preloading to each rolling element has been completed before the shipment from the bearing manufacturer.

  On the other hand, the preload is applied to the rolling elements constituting the wheel bearing rolling bearing unit for the drive wheels (the rear wheels of the FR vehicle, the front wheels of the FF vehicle, and all the wheels of the WD vehicle). There are many structures that are completed in a state where a rolling bearing unit for use and a constant velocity joint are combined. The operation of combining the wheel bearing rolling bearing unit with load measuring device and the constant velocity joint is generally performed on an assembly line of an automobile manufacturer, which is a customer for the bearing manufacturer. It is impractical to obtain the zero and gain after combining the wheel support rolling bearing unit with load measuring device and the constant velocity joint in this assembly line.

JP 2005-31063 A JP-A-2005-140606 Motoo Aoyama, “Red Badge Super Illustrated Series / A book that shows the latest mechanics of cars”, p. 138-139, p. 146-149, Sangensha Co., Ltd./Kodansha Co., Ltd., December 20, 2001

  In view of the circumstances as described above, the present invention relates to a rolling bearing unit for a drive wheel in which preloading to each rolling element is completed by being combined with a constant velocity joint. The invention was invented to realize a technique capable of grasping the relationship between the size and the relative displacement between the outer ring and the hub constituting the unit.

A wheel bearing rolling bearing unit with a load measuring device that is an object of the present invention includes a rolling bearing unit and a load measuring device.
Of these, the rolling bearing unit includes an outer ring, a hub, and a plurality of rolling elements. Further, this outer ring has a double row outer ring raceway on the inner peripheral surface, and does not rotate even in use. The hub has a double-row inner ring raceway on the outer peripheral surface and a locking hole for engaging the drive shaft of the constant velocity joint at the center, and is rotated by the constant velocity joint during use. The Each of the rolling elements is provided between the outer ring raceways and the inner ring raceways with a plurality of preloads applied to each row.
The hub is composed of a hub body and an inner ring that is fitted and fixed to the inner end of the hub body. Of these, the hub body is an outer peripheral portion of the outer peripheral surface in the axial direction. In contrast, the outer side in the width direction is said to be attached to the vehicle, while the central side is said to be “inner” in the axial direction in the state of being attached to the automobile. In the same way, the inner ring raceway of the double row inner ring raceways is provided in the middle part, and the small-diameter step part is provided at the inner end part. And the said inner ring | wheel is externally fitted by this small diameter step part. The inner ring raceway on the outer side in the axial direction can be formed directly on the outer peripheral surface of the intermediate portion of the hub body, or can be formed on the outer peripheral surface of another inner ring that is fitted and fixed to the intermediate portion.

On the other hand, the load measuring device includes a sensor for detecting a physical quantity that changes in accordance with a rotation state of the hub or a portion that rotates as the hub rotates, and the outer ring and the sensor based on a detection signal of the sensor. And an arithmetic unit for obtaining a load acting between the hub and the hub.
Data (zero point and gain or map) representing the relationship between the detection signal and the load acting between the outer ring and the hub is recorded in the memory of the arithmetic unit.
This data was obtained by applying a preload of the same size as the preload applied when using the wheel bearing rolling bearing unit to each rolling element by pressing the inner ring axially outward against the hub body. In this state, the hub is rotated while applying a load having a different magnitude between the outer ring and the hub, and the detection signal of the sensor is measured. .

The present invention as described above can be implemented by, for example, the conventionally known structure described in FIGS. 8 to 12 described above or the structure of the prior invention illustrated in FIGS. 13 to 20 described above.
When implemented with a conventionally known structure described in FIGS. 8 to 12, as described in claim 2, the load measuring device is based on the revolution speed of the rolling elements of at least one row, Measure the load acting between the hub and outer ring.
On the other hand, when implemented with the structure of the prior invention shown in FIGS. 13 to 20, the load measuring device is a hub or a part of a rotating member that rotates together with the hub. The load acting between the hub and the outer ring is measured based on the displacement of the encoder fixed concentrically with the hub or the rotating member. The rotating member may be a disc brake rotor or a constant velocity joint.

  According to a fourth aspect of the present invention, there is provided a method for manufacturing a wheel bearing rolling bearing unit with a load measuring device, wherein the inner ring is attached to the hub body in order to produce the wheel supporting rolling bearing unit with a load measuring device as described above. By pressing outward in the axial direction, a preload having the same magnitude as the preload applied when the wheel bearing rolling bearing unit is used is applied to each rolling element. Further, in this state, the hub is rotated while applying different loads, each of which is known, between the outer ring and the hub, and the detection signal of the sensor is measured. Then, after obtaining data representing the relationship between the detection signal and the load acting between the outer ring and the hub, the data or a code representing the data is recorded together with an article such as an IC tag or a piece of paper. The wheel bearing rolling bearing unit with load measuring device is shipped.

In order to apply the preload to each rolling element, the inner ring is pressed against the hub body in the axially outward direction. For example, as described in claim 5, for a constant velocity joint constituting a constant velocity joint A hub is clamped between the axially outer end surface of the outer ring and the axially inner end surface of the nut screwed into the tip end portion of the drive shaft constituting the constant velocity joint.
In this case, for example, as described in claim 6, the axial outer end surface of the outer ring for the constant velocity joint is an axial inner end surface of the inner ring, and the axial inner end surface of the nut is an axial outer end surface of the hub body. The inner ring is pressed outward in the axial direction against the hub body by rotating the nut by a predetermined angle from the state where each is in light contact. A preload having the same magnitude as the preload applied when the wheel bearing rolling bearing unit is used is applied to each rolling element.
Alternatively, in order to press the inner ring axially outward against the hub body in order to apply the preload to each of the rolling elements, as described in claim 7, the front end surface is axially inward of the inner ring. The inner ring is pressed outward in the axial direction against the hub body by a pressing jig abutted against the end face.

  According to the present invention configured as described above, with respect to a rolling bearing unit for a drive wheel, in which preloading to each rolling element is completed by being combined with a constant velocity joint, a bearing manufacturer can determine the load applied to the unit. It is possible to grasp the relationship between the size and the fluctuation amount of the detection signal of the sensor (based on the relative displacement between the outer ring and the hub constituting this unit). Then, the data representing the grasped relationship is recorded on an IC tag or printed on a piece of paper as a barcode, and sent to an automobile manufacturer together with a wheel bearing rolling bearing unit with a sensor assembled thereto. The automobile manufacturer then combines the wheel bearing rolling bearing unit and the constant velocity joint to give each rolling element the same preload as when the above relationship was grasped, and to transmit data representing this relationship to the vehicle body side. Record in the memory of the computing unit to be installed. Alternatively, a plurality of (for example, ten to several tens) patterns showing the relationship between the magnitude of the load and the fluctuation amount of the detection signal of the sensor are prepared, and the bearing manufacturer has a wheel bearing rolling bearing unit with the load measuring device. Can be determined, and a code representing the corresponding pattern can be displayed on an article such as a piece of paper. In this case, the automobile manufacturer stores the relationship of the corresponding pattern in the memory in the arithmetic unit based on this code.

  As a result, in the automobile manufacturer, the wheel support rolling bearing unit and the constant velocity joint are combined under a predetermined condition, and data recorded on the IC tag or printed as a barcode is stored in the calculator. The load applied to the rolling bearing unit for the drive wheel can be obtained with high accuracy simply by recording in the memory or setting the pattern. In other words, in order to accurately determine the load applied to the rolling bearing unit for the drive wheel, the wheel support rolling bearing unit with load measuring device is combined with the constant velocity joint on the assembly line of the automobile manufacturer, and then the zero point and gain are combined. You don't have to do what you say you want.

[First example of embodiment]
1-4 show a first example of an embodiment of the present invention corresponding to claims 1 and 3 to 6. This example shows a state in which the present invention is carried out with respect to the wheel bearing rolling bearing unit with a load measuring device of the prior invention described in FIGS. Since the structure of the wheel bearing rolling bearing unit with load measuring device is basically the same as described above, the same parts are denoted by the same reference numerals, and the duplicate description is omitted. The description will focus on the part that has not been described, the part that is different from the structure described above, and the characteristic part of this example.

  The hub 11b is formed by combining a hub body 23 and an inner ring 24. Of these, the hub body 23 has a flange 25 for supporting and fixing the wheel on the axially outer portion (left side in FIGS. 1 to 3) of the outer peripheral surface, and the double-row inner ring raceways 13 and 13 in the middle portion. The inner ring raceway 13 on the outer side in the axial direction is formed, and the small-diameter step portion 26 is formed on the inner end portion. Further, the inner ring 24 has an inner end in the axial direction protruding slightly inward in the axial direction from the inner end surface in the axial direction of the hub body 23 in a state where the inner ring 24 is externally fitted to the small diameter step portion 26. A drive shaft 28 constituting a constant velocity joint 27 is spline-engaged with the spline hole 20 formed at the center of the hub body 23 so as to be inserted from the inner side to the outer side in the axial direction. An axial inner end surface of the nut 29 screwed into a portion protruding from the spline hole 20 at the tip end of the drive shaft 28 and an axial outer end surface of the constant velocity joint outer ring 30 constituting the constant velocity joint 27. The hub 11b is sandwiched between the rolling elements 8 and 8, and an appropriate preload is applied to each of the rolling elements 8 and 8 (same as in use).

  On the outer peripheral surface of the hub 11b in the axial direction, an encoder 15c, which is formed of a magnetic metal plate with a cross-sectional crank shape and an annular shape as a whole, is externally fitted and fixed. The encoder 15c is formed with "<"-shaped through-holes 17d, 17d at equal intervals, such as by continuing the through-holes 17a, 17b constituting the encoder 15a shown in FIG. is doing. Further, a pair of sensors 16c and 16d incorporated in a sensor unit 4b fitted in a mounting hole 3b formed in the axial direction intermediate portion of the outer ring 1 is formed with the through holes 17d and 17d in the encoder 15c. The axial load acting between the hub 11b and the outer ring 1 can be measured so as to face the portion.

  Data representing the relationship between the detection signals of the sensors 16c and 16d and the load acting between the outer ring 1 and the hub 11b regarding the wheel bearing rolling bearing unit with a load measuring device configured as described above. The operation for obtaining the zero and the gain or the map is performed as follows. First, the outer ring 1 is supported on the support frame 31. For this purpose, in the illustrated example, the inner end of the outer ring 1 in the axial direction is fitted into the support frame 31, and the support frame 31 and the mounting flange 32 provided on the outer peripheral surface of the outer ring 1 are It is fixed with bolts. The support frame 31 supports the fixed frame 33 through a plurality of axial load applying actuators 34 and 34 and one to a plurality of radial load applying actuators 35 so as to allow slight displacement. . Each of these actuators 34 and 35 is a double-acting type capable of applying a force in both directions of expansion and contraction. Accordingly, the outer ring 1 can be given axial loads in both directions with respect to the axial direction and radial loads in both the upper and lower directions. Depending on the function required for the wheel support rolling bearing unit with the load measuring device, it is possible to use a single-acting actuator capable of applying only a force in the extending direction as the actuators 34 and 35. . In this case, the support frame 31 may not be coupled and fixed to the mounting flange 32 but may be just abutted.

  On the other hand, the hub 11b supports only rotation in a state in which displacement in the axial direction and radial direction is suppressed. For this purpose, for example, the constant velocity joint outer ring 30 coupled and fixed to the hub 11b is supported on a rotation support portion provided in a part of the fixed frame 33 so as not to rattle and to be rotatable. A coupling 37 is coupled and fixed to a wheel support flange 25 provided on the outer peripheral surface of the hub 11b in the axial direction, and the coupling 37 is rotationally driven by a motor 38. When obtaining the above data, the coupling 37 is supported by a rotation support portion (not shown) so that only the rotation can be freely performed in a state in which the displacement in the axial direction and the radial direction is suppressed.

  In order to obtain the data, while the hub 11b is rotated by the motor 38, predetermined (known) axial loads and radial loads (and moments as necessary) are applied to the hub 11b by the actuators 34 and 35. Give. The direction of the load or force to be applied is determined according to the direction of the load or force to be obtained in the state of being actually assembled to the automobile (matching the direction of the load or force to be obtained). The signals representing the axial load and the radial load determine the data together with the signal representing the rotational speed of the motor 38 (the hub 11b driven to rotate by the motor 38) and the detection signals of the pair of sensors 16c and 16d. Input to the data calculator. Then, the data calculation computing unit calculates data representing the relationship between the detection signals of the sensors 16c and 16d and at least one of the axial load and the radial load, and an IC chip (IC tag). ) Etc. or printed as a barcode. Therefore, the bearing manufacturer does not separate the article such as a piece of paper on which the IC chip or the bar code is printed, together with the rolling bearing unit for supporting the wheel with the load measuring device (among the components other than the arithmetic unit) (by sticking or the like). Send it to the car manufacturer. The constant velocity joint 27 is used to obtain the data, and is removed from the wheel bearing rolling bearing unit with a load measuring device and used for the next measurement work prior to transport to the automobile manufacturer.

  In any case, an automobile manufacturer that has delivered the IC chip or the paper piece and the wheel bearing rolling bearing unit with the load measuring device assembles the wheel supporting rolling bearing unit with the load measuring device into the suspension device, and FIG. As shown in FIG. 3, the hub 11b of the wheel bearing rolling bearing unit with load measuring device and the constant velocity joint 27 are coupled and fixed. This coupling and fixing work is performed under the same conditions as when the hub 11b and the constant velocity joint 27 are coupled and fixed by the bearing manufacturer in order to obtain the above data. Accordingly, in a state where the hub 11b and the constant velocity joint 27 are coupled and fixed by an automobile manufacturer, a preload having the same magnitude as that obtained when the data is obtained by the bearing manufacturer is applied to the rolling elements 8 and 8. . Therefore, if data recorded on an article such as an IC chip or a piece of paper is recorded in the memory of an arithmetic unit provided on the vehicle body side, the hub 11b and the hub 11b can be used based on the detection signals of the sensors 16c and 16d. The load applied to the outer ring 1 (in this example, at least an axial load) can be obtained with high accuracy.

  As is apparent from the above description, when the present embodiment is implemented, it is important that the hub manufacturer 11b and the constant velocity joint 27 are coupled and fixed under the same conditions by the bearing manufacturer and the automobile manufacturer. Therefore, a coupling and fixing method for combining the hub 11b and the constant velocity joint 27 under the same conditions will be described. In order to combine the hub 11b and the constant velocity joint 27, first, the drive shaft 28 constituting the constant velocity joint 27 is inserted from the inner side to the outer side in the spline hole 20 formed in the central portion of the hub body 23. In this state, engage the spline. Next, as shown in FIG. 2, a nut 29 is screwed into a portion protruding from the spline hole 20 at the tip of the drive shaft 28. In this state, a gap 39 exists between the outer end surface in the axial direction of the outer ring 30 for the constant velocity joint and the inner ring 24. Of course, in this state, no preload is applied to the rolling elements 8, 8.

  When the nut 29 is rotated in the tightening direction from this state, the drive shaft 28 is drawn into the spline hole 20, and the axial outer end surface of the constant velocity joint outer ring 30 and the inner ring 24 as shown in FIG. Are in contact with the axially inner end surface. When the nut 29 is further tightened from this state, a preload is applied to the rolling elements 8 and 8. Accordingly, until the both end faces come into contact with each other (the state shown in FIG. 2), the resistance to rotating the nut 29 in the tightening direction is limited to the frictional resistance between the threaded portion and the spline engaging portion. The torque required to rotate the nut 29 may be small as shown by a part parallel to the horizontal axis in the solid line in FIG.

  On the other hand, in order to rotate the nut 29 in the tightening direction after the both end surfaces are in contact with each other, each component member (hub main body) existing between the nut 29 and the outer ring 30 for the constant velocity joint is used. 23, the inner ring 24, and the rolling elements 8, 8) need to be elastically deformed. Accordingly, the torque required to rotate the nut 29 in the tightening direction after the both end surfaces are in contact with each other is represented by the portion b of the solid line in FIG. 4A inclined with respect to the horizontal axis. , Grows rapidly compared to before. Therefore, it is possible to easily and reliably detect that the axial outer end surface of the constant velocity joint outer ring 30 and the axial inner end surface of the inner ring 24 are in contact with each other by setting an appropriate threshold. On the other hand, the value of the preload applied to each of the rolling elements 8, 8 is the amount of elastic deformation of each component (the rolling surface of each of the rolling elements 8, 8 and the outer ring races 2, 2 and the inner ring races 13, 13. The dimension in the axial direction of the negative gap existing between The amount of elastic deformation (the dimension of the negative gap in the axial direction) is proportional to the rotation angle of the nut 29.

  Then, from the moment when the torque required to rotate the nut 29 in the tightening direction suddenly increases, the nut 29 is rotated by a predetermined angle set in advance according to the preload value to be applied. A predetermined preload can be applied to each rolling element 8, 8. If such a preload is applied by the bearing manufacturer and the automobile manufacturer, as described above, the load applied between the hub 11b and the outer ring 1 is accurately determined based on the detection signals of the sensors 16c and 16d. You can ask well.

  As described above, after determining the moment when the axial outer end surface of the constant velocity joint outer ring 30 and the axial inner end surface of the inner ring 24 contact each other, the nut 29 is further tightened in a tightening direction by a predetermined angle. In order to rotate the nut 29, a device for measuring the torque required to rotate the nut 29 is required in addition to the tightening device for tightening the nut 29. For this reason, the cost of the device for applying a predetermined preload to each of the rolling elements 8, 8 increases, and the work for applying the preload may be troublesome. As described later, as described later (as shown in FIG. 5), when combining the wheel bearing rolling bearing unit with load measuring device and the constant velocity joint 27, the drive shaft 28 is inserted into the spline hole 20, and the press machine. This also occurs when the press-fitting method is used.

  On the other hand, after the nut 29 is tightened with a constant torque (specified torque), which is insufficient for preloading, but sufficient for pulling the drive shaft 28 into the spline hole 20, If the nut 29 is rotated by a predetermined angle set in advance according to the preload value to be applied, the above-described problems can be solved. Such a preload application method will be described with reference to FIG. The prescribed torque is slightly larger than the torque corresponding to the frictional resistance between the screwing portion and the spline engaging portion (corresponding to the range of the solid line a in FIG. 4A) shown by the broken line c. Therefore, if the nut 29 is rotated in the tightening direction with the specified torque indicated by the d portion of the solid line in FIG. 4, the drive shaft 28 is drawn into the spline hole 20, and the constant velocity joint outer ring 30. The axially outer end surface and the axially inner end surface of the inner ring 24 can be brought into contact with each other.

  Therefore, from this state, the nut 29 is rotated by a predetermined angle set in advance according to the value of the preload to be applied, as shown by the part b of the solid line in FIG. Thus, a predetermined preload can be applied to each of the rolling elements 8, 8. When the nut 29 is tightened in the tightening direction with the specified torque, the nut 29 is more than the moment at which both end faces are in contact with each other by an amount corresponding to the difference between the broken line c and the solid line d. ) It will be tightened excessively. Further, the frictional resistance between the threaded portion and the spline engaging portion is different for each wheel bearing rolling bearing unit with load measuring device and constant velocity joint 27. Therefore, the amount by which the nut 29 is tightened excessively varies from one to the other. However, since the frictional resistance is much smaller than the torque required for applying a preload to the rolling elements 8, 8, the absolute value of the difference between the broken line c and the d part of the solid line is also small. Therefore, as described above, the amount by which the nut 29 is tightened excessively and the absolute value of the variation thereof are small. By tightening the nut 29 as shown by the solid line in FIG. A desired preload can be applied to the moving bodies 8 and 8 with an accuracy that is not problematic in practice.

  As is clear from the above description, the bearing manufacturer combines the hub 11b and the constant velocity joint 27 only to apply a desired preload to the rolling elements 8 and 8. Therefore, instead of the constant velocity joint 27, a preload applying jig having an appropriate structure (the same tensile rigidity as that of the constant velocity joint 27) can be used to hold the hub 11b from both sides in the axial direction. In this case, the male spline formed on the outer peripheral surface of the shaft portion constituting the preload applying jig may be sized to loosely engage with the spline hole 20, or may be a simple columnar shaft. it can. When the preload applying jig is used, the nut may be tightened by a predetermined angle for applying preload as in the case of using the constant velocity joint 27, or an axial force may be applied. A sensor that can measure the preload may be built in, and the preload value may be obtained from the measured value of the sensor.

[Second Example of Embodiment]
FIG. 5 also shows a second example of an embodiment of the present invention corresponding to claims 1 and 3 to 6. In the first example of the embodiment described above, the nut 29 screwed into the tip of the drive shaft 28 is rotated in order to draw the drive shaft 28 of the constant velocity joint 27 into the spline hole 20 of the hub 11b. On the other hand, in this example, the drive shaft 28 is pushed into the spline hole 20. That is, the tip of the output rod of an actuator such as an air cylinder is abutted against the axial inner end surface of the constant velocity joint outer ring 30 constituting the constant velocity joint 27, and the axial outer end surface of the constant velocity joint outer ring 30. The drive shaft 28 is pushed into the spline hole 20 until the inner ring 24 comes into contact with the inner end surface in the axial direction of the inner ring 24. Thereafter, a nut 29 (see FIGS. 1 to 3) is screwed onto the tip of the drive shaft 28 to apply a desired preload to the rolling elements 8 and 8. Since the points other than the method when the drive shaft 28 and the spline hole 20 are spline engaged are the same as in the case of the first example of the above-described embodiment, overlapping illustrations and descriptions are omitted.

[Third example of embodiment]
FIG. 6 shows a third example of an embodiment of the present invention corresponding to claims 1, 2, and 4-6. In the case of this example, the axial load acting between the outer ring 1 and the hub 11b is determined based on the ratio between the revolution speeds of the rolling elements 8a and 8b arranged in a double row. The procedure for obtaining this load is almost the same as the conventional structure shown in FIGS. 8 to 12 described above, and a method of applying a desired preload to each of the rolling elements 8a and 8b by the bearing manufacturer and the automobile manufacturer. Since it is the same as the first example described above, overlapping illustration and description are omitted.

[Fourth Example of Embodiment]
FIG. 7 shows a fourth example of the embodiment of the invention corresponding to claims 1, 3, 4 and 7. In the case of this example, a desired preload is applied to each of the rolling elements 8 and 8 in order to obtain data (zero point and gain or map) representing the relationship between the load acting between the outer ring 1 and the hub 11b by the bearing manufacturer. Is performed without using the constant velocity joint 27 (see FIGS. 1 to 3 and 5 to 6). Therefore, in the case of this example, the inner ring 24 is directed toward the hub body 23 by the pressing jig 42 provided at the tip of the output rod of the preload applying actuator 41 held by the holder 40 supported and fixed to the support frame 31. I try to press it. Although illustration is omitted, a thrust bearing is provided between the front end surface of the pressing jig 42 and the inner end surface in the axial direction of the inner ring 24 so that the rotation of the hub 11b is not transmitted to the pressing jig 42. Like.

  According to such a method of this example, a bearing manufacturer can obtain data representing the relationship between the detection signals of the sensors 16c and 16d and the load acting between the outer ring 1 and the hub 11b. Can be done efficiently. In order to apply the same preload to the rolling elements 8 and 8 when the data is obtained by the automobile manufacturer, an axial force corresponding to the pressing force of the pressing jig 42 is applied to the nut 29 (FIGS. 1 to 3). , 6)). For this reason, the relationship between the tightening torque of the nut 29 and the axial force is obtained in advance. Since the configuration and operation of other parts such as the load application method are the same as those in the first example of the above-described embodiment, overlapping illustrations and descriptions are omitted.

The present invention can also be applied to a structure for detecting a load based on the duty ratio of the detection signal of the sensor as shown in FIGS. In addition, a member that applies a known load to obtain data representing the relationship between the load acting between the outer ring and the hub by the bearing manufacturer is not limited to the outer ring, and may be a hub.
The technical idea of the present invention can also be applied to a rolling bearing unit for a driven wheel. That is, even in the case of a rolling bearing unit for a driven wheel, a nut for coupling and fixing the hub main body and the inner ring may be removed for maintenance or the like after assembly to the automobile. In such a case, by applying the technical idea of the present invention, it is possible to ensure the measurement accuracy of the load applied between the outer ring and the hub after the nut is assembled. Further, even in a wheel support rolling bearing unit having a structure in which a part of the hub body is plastically deformed and the hub body and the inner ring are coupled and fixed, if the hub body and the inner ring are disassembled, there is a possibility of reassembly. There is room to apply the technical idea of the present invention.

Sectional drawing which shows the state which calculates | requires a zero and a gain by the bearing manufacturer regarding the 1st example of embodiment of this invention. Sectional drawing which shows the state in the middle of combining a rolling bearing unit for wheel support, and a constant velocity joint by the same automobile manufacturer. Sectional drawing which shows the state which gives preload similarly combining. The diagram which shows two examples of the state which screws and tightens a nut further for preload provision. The figure similar to FIG. 2 which shows the 2nd example of embodiment of this invention. The figure similar to FIG. 1 which shows the 3rd example. The figure similar to FIG. 1 which shows the 4th example. Sectional drawing which shows the 1st example of the rolling bearing unit for wheel support with a load measuring apparatus conventionally known. The schematic diagram for demonstrating the reason for which a load is calculated | required by the structure of this 1st example. The diagram which shows the relationship between the revolution speed of the rolling element of each row | line | column, and radial load. The diagram which similarly shows the relationship between an axial load and revolution speed. Sectional drawing which shows the 2nd example of the rolling bearing unit for wheel support with a load measuring apparatus conventionally known. Sectional drawing which shows the 1st example of the rolling bearing unit for wheel support with a load measuring device which concerns on a prior invention. The perspective view of the encoder built in this 1st example. Similarly development. The diagram for demonstrating the state from which the output signal of a pair of sensor changes based on an axial load. The perspective view of the encoder integrated in the 2nd example of the rolling bearing unit for wheel support with a load measuring device concerning a prior invention. Sectional drawing which shows the 3rd example. The fragmentary perspective view of the encoder integrated in this 3rd example. The side view which looked at the encoder integrated in the 4th example of the rolling bearing unit for wheel support with a load measuring device which concerns on a prior invention from the axial direction.

Explanation of symbols

1, 1a Outer ring 2 Outer ring raceway 3, 3a, 3b Mounting hole 4, 4a, 4b Sensor unit 5, 5a Tip 6a, 6b Revolution speed detection sensor 7, 7a Rotational speed detection sensor 8, 8a, 8b, 8c Moving body 9a, 9b Cage 10a, 10b Revolution speed detection encoder 11, 11a, 11b Hub 12, 12a Rotational speed detection encoder 13 Inner ring raceway 14 Cover 15, 15a, 15b, 15c Encoder 16, 16a, 16b, 16c, 16d Sensors 17a, 17b, 17c, 17d Through-holes 18a, 18b Column 19 Rim 20 Spline 21 Recess 22 Convex 23 Hub body 24 Inner ring 25 Flange 26 Small diameter step 27 Constant velocity joint 28 Drive shaft 29 Nut 30 Constant velocity joint Outer ring 31 Support frame 32 Mounting flange 33 Solid Frame 34 axial load imparted actuator 35 radial load imparted actuator 37 coupling 38 motor 39 gap 40 holder 41 preloading actuator 42 pressing jig

Claims (7)

A wheel bearing rolling bearing unit and a load measuring device;
Of these, the rolling bearing unit for wheel support has a double row outer ring raceway on the inner peripheral surface, an outer ring that does not rotate even in use, a double row inner ring raceway on the outer peripheral surface, and a constant velocity joint drive in the center. A plurality of locking holes for engaging the shaft are provided for each row between the hub that is rotationally driven by the constant velocity joint when used, and both the outer ring raceways and the inner ring raceways. Each with rolling elements provided with a preload applied thereto,
The hub is composed of a hub body and an inner ring that is externally fitted and fixed to the inner end of the hub body. Of these, the hub body has a flange for supporting and fixing the wheel on an axially outer portion of the outer peripheral surface. Similarly, an inner ring raceway on the outer side in the axial direction of the double row inner ring raceways is provided at the intermediate portion, and a small diameter step portion is provided at the inner end portion, respectively, and the inner ring is externally fitted to the small diameter step portion. And
The load measuring device includes a sensor for detecting a physical quantity that changes in accordance with a rotation state of the hub or a portion that rotates as the hub rotates, and the outer ring and the hub based on a detection signal of the sensor. And an arithmetic unit for calculating a load acting between
Data representing the relationship between the detection signal and the load acting between the outer ring and the hub is recorded in the memory of the calculator.
This data was obtained by applying a preload of the same size as the preload applied when using the wheel bearing rolling bearing unit to each rolling element by pressing the inner ring axially outward against the hub body. In this state, the hub is rotated while applying a load having a different magnitude between the outer ring and the hub, and the detection signal of the sensor is measured. Rolling bearing unit for wheel support with load measuring device.   The wheel support rolling bearing with a load measuring device according to claim 1, wherein the load measuring device measures a load acting between the hub and the outer ring based on a revolution speed of at least one row of rolling elements. unit.   The load measuring device applies a load acting between the hub and the outer ring on the hub or a part of the rotating member that rotates together with the hub, based on the displacement of the encoder fixed concentrically with the hub or the rotating member. The rolling bearing unit for supporting a wheel with a load measuring device according to claim 1, which is to be measured.   A method for manufacturing a wheel support rolling bearing unit with a load measuring device for obtaining the wheel supporting rolling bearing unit with a load measuring device according to any one of claims 1 to 3, wherein the inner ring is a hub body. In the state where the preload of the same size as the preload applied when using the wheel bearing rolling bearing unit is applied to each rolling element by pressing outward in the axial direction, The relationship between the detection signal and the load acting between the outer ring and the hub is measured by measuring the detection signal of the sensor by rotating the hub while applying different loads. The wheel support rolling bearing with load measuring device is shipped together with the article in which the data or the code representing the data is recorded after the data representing the load is recorded. Method of manufacturing a knit.   By holding the hub between the axial outer end surface of the constant velocity joint outer ring constituting the constant velocity joint and the axial inner end surface of the nut screwed into the tip of the drive shaft constituting the constant velocity joint. The method for manufacturing a wheel bearing rolling bearing unit with a load measuring device according to claim 4, wherein the inner ring is pressed axially outward against the hub body.   Rotate the nut by a predetermined angle from the state where the axial outer end face of the outer ring for the constant velocity joint is in light contact with the axial inner end face of the inner ring and the axial inner end face of the nut is brought into slight contact with the axial outer end face of the hub body In this case, the inner ring is pressed axially outwardly with respect to the hub body, and a preload having the same magnitude as the preload applied when the wheel supporting rolling bearing unit is used is applied to each rolling element. The manufacturing method of the wheel bearing rolling bearing unit with a load measuring device described in 2.   The rolling bearing unit for supporting a wheel with a load measuring device according to claim 4, wherein the inner ring is pressed outward in the axial direction against the hub body by a pressing jig that abuts the front end surface against the inner end surface in the axial direction of the inner ring. Production method.

Images