JP2005091081A - Load measuring device for rolling bearing unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact and lightweight structure at a low cost, by which a value of load applied on a double row bearing unit is obtained accurately. <P>SOLUTION: An orbital speed value of rolling elements in the double rows is obtained by using a pair of sensors for detecting orbital speed 24a, 24b, and a rotation speed value of a turning wheel is obtained by using a sensor for detecting rotation speed 15a. The load applied on the double row bearing unit is obtained from the orbital speed value and the rotation speed value. Each of the above sensors 24a, 24b and 15a is mounted on a metal base substrate or an MID substrate 28 having a three-dimensional structure. As a result, these sensors 24a, 24b and 15a are easily positioned, and their harness is readily shared, thereby solving the above problem. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  A load measuring device for a rolling bearing unit according to the present invention relates to an improvement of a rolling bearing unit for supporting wheels of a moving body such as an automobile, a railway vehicle, and various transport vehicles. One or both of radial load and axial load) is measured and used to ensure the stability of operation of the moving body.

  For example, an automobile wheel is rotatably supported by a double row angular rolling bearing unit with respect to a suspension device. In order to ensure the running stability of automobiles, vehicle running stabilizers such as an antilock brake system (ABS), a traction control system (TCS), and a vehicle stability control system (VSC) are used. . In order to control such various vehicle running stabilizers, 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 (one or both of a radial load and an axial load) applied to the rolling bearing unit via the wheel.

  In view of such circumstances, Patent Document 1 describes a rolling bearing unit with a load measuring device capable of measuring a radial load. This conventional rolling bearing unit with a load measuring device of the first example measures a radial load and is configured as shown in FIG. A hub 2, which is a rotating wheel and is an inner ring equivalent member, is fixed to the inner diameter side of the outer ring 1 that is a stationary wheel and is an outer ring equivalent member supported by the suspension device. The hub 2 includes a hub body 4 having a rotation-side flange 3 for fixing a wheel at an outer end thereof (an end on the outer side in the width direction when assembled to a vehicle), and an inner end of the hub body 4. And an inner ring 6 that is externally fitted to the end (on the widthwise center side in the assembled state in the vehicle) and held down by a nut 5. And the double row outer ring raceways 7 and 7 each formed on the inner peripheral surface of the outer ring 1 and each of which is a stationary side track, and the double row each formed on the outer peripheral surface of the hub 2 and each of which is a rotation side track. A plurality of rolling elements 9 a and 9 b are arranged between the inner ring raceways 8 and 8, respectively, so that the hub 2 can freely rotate on the inner diameter side of the outer ring 1.

  A mounting hole 10 that diametrically penetrates the outer ring 1 is formed in a substantially vertical direction at an upper end portion of the outer ring 1 in a portion between the double row outer ring raceways 7 and 7 at an intermediate portion in the axial direction of the outer ring 1. Yes. In the mounting hole 10, a circular (rod-shaped) displacement sensor 11, which is a load measuring sensor, is mounted. This displacement sensor 11 is a non-contact type, and the detection surface provided on the front end surface (lower end surface) is closely opposed to the outer peripheral surface of the sensor ring 12 fitted and fixed to the intermediate portion in the axial direction of the hub 2. When the distance between the detection surface and the outer peripheral surface of the sensor ring 12 changes, the displacement sensor 11 outputs a signal corresponding to the amount of change.

  In the case of the conventional rolling bearing unit with a load measuring device configured as described above, the load applied to the rolling bearing unit can be obtained based on the detection signal of the displacement sensor 11. That is, the outer ring 1 supported by the vehicle suspension device is pushed downward by the weight of the vehicle, whereas the hub 2 supporting and fixing the wheel tends to stop at the same position. For this reason, the greater the weight, the greater the deviation between the center of the outer ring 1 and the center of the hub 2 based on the elastic deformation of the outer ring 1, the hub 2, and the rolling elements 9a, 9b. The distance between the detection surface of the displacement sensor 11 and the outer peripheral surface of the sensor ring 12 provided at the upper end of the outer ring 1 becomes shorter as the weight increases. Therefore, if the detection signal of the displacement sensor 11 is sent to the controller, the radial load applied to the rolling bearing unit in which the displacement sensor 11 is incorporated can be obtained from a relational expression or a map obtained beforehand through experiments or the like. Based on the load applied to each rolling bearing unit thus obtained, the ABS is appropriately controlled and the driver is informed of the poor loading state.

  In the conventional structure shown in FIG. 20, in addition to the load applied to the rolling bearing unit, the rotational speed of the hub 2 can also be detected. For this purpose, the sensor rotor 13 is fitted and fixed to the inner end portion of the inner ring 6, and the rotational speed detection sensor 15 is supported by a cover 14 attached to the inner end opening of the outer ring 1. The detection portion of the rotational speed detection sensor 15 is opposed to the detection portion of the sensor rotor 13 via a detection gap.

  When the rolling bearing unit incorporating the rotational speed detection device as described above is used, the sensor rotor 13 rotates together with the hub 2 to which the wheel is fixed, and the detected portion of the sensor rotor 13 is connected to the rotational speed detection sensor 15. When traveling in the vicinity of the detection unit, the output of the rotational speed detection sensor 15 changes. The frequency at which the output of the rotational speed detection sensor 15 changes in this way is proportional to the rotational speed of the wheel. Therefore, if the output signal of the rotational speed detection sensor 15 is sent to a controller (not shown), ABS and TCS can be controlled appropriately.

  The rolling bearing unit with a load measuring device of the first example of the conventional structure as described above is for measuring the radial load applied to the rolling bearing unit, but the structure for measuring the axial load applied to the rolling bearing unit is also, It is described in Patent Document 2 and the like and has been conventionally known. FIG. 21 shows a rolling bearing unit with a load measuring device described in Patent Document 2 for measuring an axial load. In the case of the second example of the conventional structure, the rotation side flange 3a for supporting the wheel is fixed to the outer peripheral surface of the outer end portion of the hub 2a which is a rotating wheel. In addition, a fixed-side flange 17 for fixing the outer ring 1a to the knuckle 16 constituting the suspension device is fixed to the outer peripheral surface of the outer ring 1a which is a stationary wheel. A plurality of rolling rings are respectively provided between the double row outer ring raceways 7 and 7 formed on the inner peripheral surface of the outer ring 1a and the double row inner ring raceways 8 and 8 formed on the outer peripheral surface of the hub 2a. By providing the moving bodies 9a and 9b so as to be able to roll, the hub 2a is rotatably supported on the inner diameter side of the outer ring 1a.

  Further, a load sensor 20 is attached to a part surrounding the screw hole 19 for screwing the bolt 18 for connecting the fixed side flange 17 to the knuckle 16 at a plurality of positions on the inner side surface of the fixed side flange 17. Has been established. Each load sensor 20 is sandwiched between the outer side surface of the knuckle 16 and the inner side surface of the fixed-side flange 17 in a state where the outer ring 1 a is supported and fixed to the knuckle 16.

  In the case of the load measuring device of the rolling bearing unit of the second example having such a conventional structure, when an axial load is applied between a wheel (not shown) and the knuckle 16, the outer surface of the knuckle 16 and the fixed side flange 17 The inner surface strongly presses the load sensors 20 from both sides in the axial direction. Therefore, the axial load applied between the wheel and the knuckle 16 can be obtained by summing up the measured values of the load sensors 20. Although not shown, Patent Document 3 describes a method of obtaining the revolution speed of the rolling element from the vibration frequency of a member corresponding to an outer ring having a reduced rigidity, and measuring the axial load applied to the rolling bearing. ing.

  In the case of the first example of the conventional structure shown in FIG. 20 described above, the displacement applied to the rolling bearing unit is measured by measuring the displacement in the radial direction between the outer ring 1 and the hub 2 by the displacement sensor 11. However, since the displacement amount in the radial direction is small, it is necessary to use a highly accurate displacement sensor 11 in order to obtain this load with high accuracy. Since high-precision non-contact sensors are expensive, it is inevitable that the cost of the entire rolling bearing unit with a load measuring device increases.

  In the case of the second example of the conventional structure shown in FIG. 21 described above, it is necessary to provide the same number of load sensors 20 as the bolts 18 for supporting and fixing the outer ring 1a to the knuckle 16. For this reason, coupled with the fact that the load sensor 20 itself is expensive, it is inevitable that the cost of the entire load measuring device of the rolling bearing unit is considerably increased. Further, the method described in Patent Document 3 requires that the rigidity of a part of the outer ring equivalent member be lowered, and it may be difficult to ensure the durability of the outer ring equivalent member.

  In view of such circumstances, the present inventors have previously described this rolling bearing unit based on the revolution speed of a pair of rolling elements (balls) constituting a rolling bearing unit which is a double row angular ball bearing. An invention relating to a load measuring device for a rolling bearing unit that measures a radial load or an axial load applied to the bearing is performed (Japanese Patent Application Nos. 2003-171715 and 172483). In the case of the load measuring device of the rolling bearing unit according to the present invention, in order to obtain the revolution speed of the rolling elements in each row, it is possible to detect the rotation speed of the cage holding the rolling elements in each row. Is effective in terms of obtaining high resolution.

  When the load measuring device for a rolling bearing unit according to the above invention is implemented, it is desired to realize a structure that efficiently extracts output signals from a plurality of speed detection sensors. That is, in order to measure the radial load or the axial load applied to the rolling bearing unit based on the revolution speed of the rolling elements in each row, at least (even when the rotation speed of the rotating wheel is constant) at least two speed detection sensors are used. I need one. Further, when the rotational speed of the rotating wheel fluctuates, a total of three sensors including a speed detection sensor for measuring the rotational speed of the rotating wheel are required to measure the loads regardless of the fluctuation. Speed detection sensors are required. Moreover, the directions of the detection surfaces of these speed detection sensors are different from each other.

  In this manner, when a plurality of speed detection sensors having different detection surface directions are mounted on a general printed circuit board, it is necessary to use a separate printed circuit board for each speed detection sensor. It is troublesome if not impossible to assemble a plurality of printed circuit boards in a limited installation space while appropriately restricting their installation positions and installation directions, and improvements are desired. Although it is possible to install a plurality of speed detection sensors without using a printed circuit board, a harness for extracting signals from these speed detection sensors or supplying power to these speed detection sensors And it becomes difficult to ensure the reliability of the joint portion (soldered portion) with the terminal (lead) of each speed detection sensor. Furthermore, regardless of whether or not a printed circuit board is used, if each of the speed detection sensors is installed separately, the power line is shared between these speed detection sensors (and grounding in the case of three wires) It is difficult to reduce the number of harnesses used in terms of space. In addition, each of the speed detection sensors must be positioned a plurality of times (the same number of times as the number of speed detection sensors) for each of these speed detection sensors. The assembly work of the unit becomes troublesome, and the manufacturing cost of the sensor unit increases.

JP 2001-21577 A Japanese Patent Laid-Open No. 3-209016 Japanese Patent Publication No.62-3365

  In view of the circumstances as described above, the present invention can be configured at low cost, does not cause problems in durability and installation space, and can measure the load applied to the rolling bearing unit. The device is realized.

The load measuring device for a rolling bearing unit according to the present invention includes a stationary wheel, a rotating wheel, a plurality of rolling elements, a pair of revolution speed detection sensors, and a calculator.
Of these, the stationary wheels do not rotate during use.
The rotating wheel is arranged concentrically with the stationary wheel and rotates when in use.
In addition, each of the rolling elements includes a pair of rows between a stationary-side track and a rotating-side track, each of which is formed in a pair of portions of the stationary wheel and the rotating wheel facing each other. It is provided so as to be able to roll with the direction of the contact angle reversed between each other.
The revolution speed detection sensors detect the revolution speeds of the rolling elements in each row.
Further, the computing unit calculates a load applied between the stationary wheel and the rotating wheel based on a detection signal sent from each revolution speed detection sensor.
A printed circuit board for mounting the pair of revolution speed detection sensors has a three-dimensional structure in which a pair of board parts arranged at a distance from each other are connected together by a connecting part. A printed circuit board.

The load measuring device of the rolling bearing unit of the present invention configured as described above is loaded on the rolling bearing unit by detecting the revolution speeds of a pair of rolling elements with different contact angle directions. The load can be measured. That is, when a load is applied to a rolling bearing unit such as a double-row angular ball bearing, the contact angle of the rolling elements (balls) changes, and the revolution speed of the rolling elements changes. Therefore, if this revolution speed is detected as the rotational speed of the cage, a load acting between the stationary wheel and the rotating wheel can be obtained.
Furthermore, since the load measuring device of the rolling bearing unit of the present invention has a plurality of speed detection sensors including a pair of revolution speed detection sensors mounted on an integrated printed board having a three-dimensional structure, The assembly work of each speed detection sensor can be facilitated, the reliability of the assembly part of each speed detection sensor can be improved, and the weight and cost can be reduced by reducing the harness.

When the present invention is implemented, preferably, a printed circuit board having a three-dimensional structure is selected from a MID (Molded Interconnection Device) board and a metal base board.
The MID substrate is a three-dimensional electric circuit in which electric lines and electrodes are formed on the surface of an injection molded product made of an insulating material such as synthetic resin. Such a MID substrate is different from the conventional multilayered two-dimensional circuit in that the molded product and the electric circuit are integrated, and the arrangement of the electric circuit can be made as desired. Large product design is possible. Therefore, if a pair of revolution speed detection sensors are mounted on the MID board, the assembly work of these revolution speed detection sensors and the connection work with the harness can be facilitated, and between these revolution speed detection sensors. The harness can be easily shared.

  The metal base substrate is obtained by providing an insulating layer on the surface of a metal plate such as a steel plate, and forming an electric line and electrodes on the surface of the insulating layer. Such a metal base substrate has good workability and can be used as a three-dimensional wiring board (three-dimensional substrate) by performing mechanical processing such as bending. Therefore, similar to the above MID board, it is possible to design a product with a high degree of freedom, such as arranging the electrical circuit as desired, and assembling the sensors for detecting both revolution speeds as in the case of using the MID board. In addition to facilitating the connection work with the harness, the harness can be easily shared between the two revolution speed detection sensors. Moreover, in the case of the metal base substrate, since the thermal conductivity is good, the temperature rise due to heat generation of the electronic component can be suppressed. In addition, when each of the revolution speed detection sensors detects the revolution speed of the rolling elements in both rows based on the magnetic change, a magnetic base plate is used so that the magnetic force between these rows can be reduced. It is possible to prevent the occurrence of interference (ensure electromagnetic shielding properties) and improve the reliability related to the revolution speed detection. As the material of the metal base substrate, any of ferrous metals such as galvanized steel sheets, aluminum, copper, and stainless steel can be adopted. However, when a magnetic detection type revolution speed detection sensor is used, it is preferable to use a ferrous metal substrate such as a galvanized steel sheet from the aspect of preventing the magnetic interference.

Preferably, as described in claim 3, the printed circuit board having a three-dimensional structure has a U-shape as a whole by connecting one end edges of a pair of substrate parts by a connecting part, or As described in claim 4, one end edges of the pair of substrate portions are connected by the connecting portion, and the other end edges or intermediate portions of the pair of substrate portions are connected by the second connecting portion. Use the whole or part of it in a square shape.
By adopting such a shape, it is possible to efficiently arrange a pair of revolution speed detection sensors arranged between a pair of rolling elements. In addition, if the structure has a square shape, the rigidity of the printed circuit board can be increased, and the accuracy of the assembly position of the pair of revolution speed detection sensors mounted on the printed circuit board can be further improved.

Preferably, as described in claim 5, one of the stationary ring and the rotating ring is an outer ring equivalent member, the other race ring is an inner ring equivalent member, and each rolling element is a ball. . Then, a pair of revolution speed detecting encoders whose characteristics are alternately changed in the circumferential direction are supported concentrically with the respective opposing side surfaces of the pair of cages holding the balls. Fix it. In addition, a pair of revolution speed detection sensors are arranged between the pair of revolution speed detection encoders, and the detection sections of the two revolution speed detection sensors are connected to each other. Opposite side faces. In addition, a plurality of rows of angular contact inner ring raceways formed on the outer peripheral surface of the inner ring equivalent member and a plurality of rows of angular contact outer ring raceways formed on the inner peripheral surface of the outer ring equivalent member are provided. A contact angle of the back combination type is given to the ball.
With this configuration, it is possible to efficiently arrange the pair of revolution speed detection sensors and to make the entire load measuring device of the rolling bearing unit compact.

Preferably, as described in claim 6, the computing unit is arranged between the stationary wheel and the rotating wheel based on the ratio of the revolution speed of the rolling element of one row and the revolution speed of the other row. The axial load applied to is calculated.
If comprised in this way, the axial load added to a rolling bearing unit is calculated | required.
Preferably, as described in claims 7 and 8, a rotational speed detection sensor is installed at a connection portion of the printed circuit board having a three-dimensional structure, and the detection portion of the rotational speed detection sensor is connected to the rotating wheel. The rotational speed of the rotating wheel is made freely detectable by being opposed to the detection surface of the rotational speed detecting encoder fitted and fixed to the intermediate portion.
Then, the computing unit is configured to calculate the stationary wheel and the rotating wheel based on a ratio between the revolution speed of the rolling elements in one row and the revolution speed of the rolling elements in the other row and the rotational speed of the rotating wheels. Or the difference between the revolution speed of the rolling elements in one row and the revolution speed of the rolling elements in the other row, and the rotating wheel The axial load applied between the stationary wheel and the rotating wheel is calculated on the basis of the ratio to the rotational speed of (in the case of the invention described in claim 8).
If comprised in this way, the load (radial load and thrust load) applied to a rolling bearing unit can be calculated | required correctly irrespective of the fluctuation | variation of the rotational speed of the said rotating wheel.

Further, preferably, as described in claim 9, an adder circuit that synthesizes output signals of a plurality of speed detection sensors and sends them to one harness and a signal sent through the one harness are separated. And a separation circuit for extracting the output signal of each of the speed detection sensors.
With this configuration, despite the use of a plurality of speed detection sensors including a pair of revolution speed detection sensors, the number of harnesses used can be determined for each speed detection sensor. Less than the total number. For this reason, the assembly work of the load measuring device of the rolling bearing unit can be facilitated, and the weight and manufacturing cost can be reduced.

  1 to 9 show an embodiment of the present invention. In this embodiment, the load (radial load and axial load) applied to the rolling bearing unit for supporting the driven wheel of the automobile (the front wheel of the FR car, the RR car, the MD car, the rear wheel of the FF car) is measured. A case where the present invention is applied to a load measuring device of a rolling bearing unit is shown. Since the configuration and operation of the rolling bearing unit itself are the same as those of the conventional structure shown in FIG. 20, the same reference numerals are given to the same parts, and the redundant description is omitted or simplified. The description will focus on the characteristic part.

An inner surface of a double-row angular type inner ring raceway 8, 8 formed on the outer peripheral surface of the hub 2, which is a rotating wheel and an inner ring equivalent member, respectively, and an outer ring 1 which is a stationary wheel and an outer ring equivalent member. The rolling elements (balls) 9a and 9b are divided into double rows (2 rows) between the double row angular outer ring raceways 7 and 7, each of which is a stationary side raceway. The hub 2 is rotatably supported on the inner diameter side of the outer ring 1 by providing a plurality of rolls while being held by the cages 21a and 21b. In this state, the rolling elements 9a and 9b in each row are provided with contact angles α _a and α _b (FIG. 2) in the opposite directions and the same magnitude, so that the double-row angular contact of the rear combination type Configures a ball bearing. Sufficient preload is applied to the rolling elements 9a and 9b in each row so as not to be lost due to an axial load applied during use. When such a rolling bearing unit is used, the outer ring 1 is supported and fixed to a suspension device, and a braking disk and a wheel of a wheel are supported and fixed to the rotation side flange 3 of the hub 2.

  A mounting hole 10a is formed in the axially intermediate portion of the outer ring 1 constituting the rolling bearing unit as described above between the double row outer ring raceways 7 and 7 so as to penetrate the outer ring 1 in the radial direction. ing. Then, the sensor unit 22 is inserted into the mounting hole 10 a from the radially outer side of the outer ring 1 to the inner side, and the detection unit 23 provided at the tip of the sensor unit 22 is inserted from the inner peripheral surface of the outer ring 1. It is protruding. The detection unit 23 is provided with a pair of revolution speed detection sensors 24a and 24b and one rotation speed detection sensor 15a.

  Among these, the revolution speed detection sensors 24a and 24b are for measuring the revolution speed of the rolling elements 9a and 9b arranged in the double row. Each detection surface is arrange | positioned on the both sides | surfaces regarding (the left-right direction of FIGS. 1-2). In this example, the revolution speed detection sensors 24a and 24b detect the revolution speeds of the rolling elements 9a and 9b arranged in the double row as the rotation speeds of the cages 21a and 21b. For this reason, in the case of this example, the rim portions 25 and 25 constituting the retainers 21a and 21b are arranged on the sides facing each other. Then, revolving speed detection encoders 26a and 26b each having a ring shape are attached and supported on the surfaces of the rim portions 25 and 25 facing each other over the entire circumference. The characteristics of the detected surfaces of the encoders 26a and 26b are changed alternately and at equal intervals in the circumferential direction, and the rotational speeds of the cages 21a and 21b are changed by the revolution speed detection sensors 24a and 24b. Detectable.

  For this purpose, the detection surfaces of the revolution speed detection sensors 24a and 24b are made to face each other and face to face, which are the detection surfaces of the revolution speed detection encoders 26a and 26b. The distances (detection gaps) between the detected surfaces of the revolution speed detection encoders 26a and 26b and the detection surfaces of the revolution speed detection sensors 24a and 24b are the inner surfaces of the pockets of the retainers 21a and 21b. And larger than a pocket gap, which is a gap between the rolling elements 9a and 9b, and preferably 2 mm or less. If the detection gap is equal to or less than the pocket gap, it is not preferable because the detected surface and the detection surface may rub against each other when the cages 21a and 21b are displaced by the pocket gap. On the contrary, if the detection gap exceeds 2 mm, it becomes difficult to accurately measure the rotations of the revolution speed detecting encoders 26a and 26b by the revolution speed detecting sensors 24a and 24b.

  On the other hand, the rotational speed detection sensor 15a is for measuring the rotational speed of the hub 2, which is a rotating wheel, and is provided on the tip surface of the detecting portion 23, that is, on the radially inner end surface of the outer ring 1. The detection surface is arranged. A cylindrical rotational speed detecting encoder 27 is externally fitted and fixed between the double-row inner ring raceways 8 and 8 at the intermediate portion of the hub 2. The detection surface of the rotation speed detection sensor 15a is opposed to the outer peripheral surface, which is the detection surface of the rotation speed detection encoder 27. The characteristics of the surface to be detected of the rotational speed detecting encoder 27 are changed alternately and at equal intervals in the circumferential direction so that the rotational speed of the hub 2 can be detected by the rotational speed detecting sensor 15a. The measurement gap between the outer peripheral surface of the rotational speed detection encoder 27 and the detection surface of the rotational speed detection sensor 15a is also suppressed to 2 mm or less.

  As the encoders 26a, 26b, and 27, those of various structures that have been used for detecting the rotational speed of the wheel in order to obtain ABS and TCS control signals can be used. For example, as the encoders 26a, 26b, and 27, as shown in FIG. 3, a multi-pole magnet having N poles and S poles arranged alternately and at equal intervals on the detection surface (side surface or outer peripheral surface). Can be preferably used. However, a simple encoder made of a magnetic material or one whose optical characteristics are changed alternately and at equal intervals in the circumferential direction can be used (in combination with an optical rotation speed detection sensor). is there. Regardless of which structure is used as each of the encoders 26a, 26b, and 27, the output signal of each rotational speed detection sensor changes at a frequency proportional to the rotational speed.

  In the case of this example, as each of the revolution speed detection encoders 26a and 26b, an annular permanent magnet in which S poles and N poles are alternately arranged at equal intervals on the side surface in the axial direction, which is a detected surface. I use it. Such revolving speed detecting encoders 26a and 26b are bonded and fixed to the side surfaces of the rim portions 25 and 25 of the holders 21a and 21b, which are separately manufactured, or these holders 21a and 21b. When injection molding is performed, insert molding is performed by setting each of the revolution speed detecting encoders 26a and 26b in the cavity. Which method is adopted is selected according to the cost, the required bond strength, and the like.

  In addition, as each of the revolution speed detection sensors 24a and 24b and the rotation speed detection sensor 15a, which are sensors for detecting the rotation speed, magnetic rotation speed detection sensors can be preferably used. As the magnetic rotational speed detection sensor, an active sensor incorporating a magnetic detection element such as a Hall element, Hall IC, magnetoresistive element (MR element, GMR element), or MI element can be preferably used. . Such a magnetic detection element is preferably formed as an IC package. In this case, the IC package may be SMT or lead type. In order to construct an active type rotational speed detection sensor incorporating such a magnetic detection element, for example, one side surface of the magnetic detection element is directly or via a stator made of a magnetic material, the magnetization direction of the permanent magnet. Abut against one end surface (when a magnetic material encoder is used), and the other side surface of the magnetic detection element directly or via a magnetic material stator to the detection surface of each encoder 26a, 26b, 27 Make them face each other. In this example, since a permanent magnet encoder is used, a permanent magnet on the sensor side is unnecessary.

  Regardless of which type of encoder 26a, 26b, 27 is used, and which type of sensor 24a, 24b, 15a is used, The sensors 24a, 24b, and 15a are mounted on the MID substrate 28 as shown in FIG. The MID substrate 28 is integrally formed as a U-shape as a whole by injection molding of synthetic resin, and a pair of substrate portions 29a and 29b arranged in parallel with each other, and both the substrates. The connection part 30 which connects the end edges of the parts 29a and 29b mutually is provided. In such a MID substrate 28, on the surfaces of the portions including both the substrate portions 29a and 29b and the surfaces of the connecting portions 30, an electric line and an electrode are formed with a metal foil such as copper to form a three-dimensional structure. An electric circuit is configured.

  Of the sensors 24a, 24b, and 15a, the pair of revolution speed detection sensors 24a and 24b are mounted on a portion near one end of the outer surfaces (side surfaces opposite to each other) of the substrate portions 29a and 29b. . The rotational speed detection sensor 15a is also mounted at the center of the outer surface of the connecting portion 30 (the surface opposite to the bending direction of the two substrate portions 29a and 29b). That is, a plurality of terminals for each of the sensors 24a, 24b, and 15a are soldered to a part of the electric line, so that the sensors 24a, 24b, and 15a are coupled and fixed to the MID board 28. Further, the end of each of the electric lines that is electrically connected to the terminals of each of the sensors 24a, 24b, and 15a is the other end (the upper end of FIGS. 4 to 6) of one (right of FIGS. 4 and 5) of the board portion 29b. ). Further, a plurality of through holes (through holes) 31, 31 penetrating in the thickness direction of the substrate portion 29 b are formed in the other end portion of the substrate portion 29 b and the end portions of the electric lines. (4 in the illustrated example) are formed.

  A plurality of such through holes 31, 31 are provided for supplying power to the sensors 24a, 24b, 15a or for taking out detection signals from the sensors 24a, 24b, 15a (example shown in the figure). Then, the ends of the conducting wires of the four harnesses 32 and 32 are inserted. And by soldering the ends of the conductors of the harnesses 32 and 32 and the ends of the electric lines, the power supply to the sensors 24a, 24b, and 15a and the sensors 24a, 24b, The detection signal 15a can be taken out freely. In the illustrated example, three harnesses 32 and 32 for taking out detection signals of the sensors 24a, 24b and 15a are provided, and one harness 32 for supplying power to the sensors 24a, 24b and 15a is provided. Each book is provided. The harnesses 32 and 32 are taken out from the center side of the MID board 28 so that the harnesses 32 and 32 do not protrude from the MID board 28 (to the right in FIG. 5).

  The MID substrate 28 on which the sensors 24a, 24b, and 15a are mounted as described above is embedded and supported in the tip portion of a synthetic resin holder 33 as shown in FIGS. The unit 22 is assumed. The sensor unit 22 includes an insertion portion 34 that is inserted into the outer ring 1 through the attachment hole 10a, a mounting flange 35 that is provided at a base end portion (the upper end portion in FIGS. 5 and 6) of the insertion portion 34, A take-out portion 36 provided at the center of the outer surface of the mounting flange 35 (the surface opposite to the insertion portion 34 and the upper surface in FIGS. 5 and 6) is provided. And the cable 37 which bundled the said multiple harnesses 32 and 32 is taken out from this taking-out part 36. FIG. Further, at the four corners of the mounting flange 35, through holes 38, 38 for inserting screws for fixing the mounting flange 35 to the outer peripheral surface of the outer ring 1 are formed.

  As shown in FIG. 8, the cross-sectional shape of the insertion portion 34 is an oval shape in which both ends of a pair of flat surfaces 39, 39 parallel to each other are continuous with convex curved surfaces. And the detection part of said one pair of revolution speed detection sensors 24a and 24b is arrange | positioned in each said flat surface 39 and 39 part. With this configuration, the detection parts of the revolution speed detection sensors 24a and 24b embedded in the insertion part 34 are made to face and face the detection surfaces of the revolution speed detection encoders 26a and 26b. Yes. Both edge portions of both the substrate portions 29a and 29b are inclined in such a direction that the distance between the substrate portions 29a and 29b becomes narrower toward the outer surface, so that the width dimension of the outer surfaces of both the substrate portions 29a and 29b is larger than necessary. I try not to be. The two substrate portions 29a and 29b are completely embedded in the holder 33.

In the case of the load measuring device of the rolling bearing unit of the present embodiment configured to include the sensor unit 22 as described above, the detection signals of the sensors 24a, 24b, 15a are the harnesses 32, 32 (cable 37). To the arithmetic unit (not shown). Then, based on the detection signals sent from the sensors 24a, 24b, 15a, the arithmetic unit applies one or both of the radial load and the axial load applied between the outer ring 1 and the hub 2. Is calculated. For example, when the radial load is obtained, the computing unit obtains the sum of the revolution speeds of the rolling elements 9a and 9b in each row detected by the revolution speed detection sensors 24a and 24b, and the sum and the rotation speed. The radial load is calculated based on the ratio to the rotational speed of the hub 2 detected by the detection sensor 15a. The axial load is determined based on the ratio of the revolution speeds of the rolling elements 9a and 9b in the respective rows detected by the respective revolution speed detection sensors 24a and 24b, or the revolutions of the rolling elements 9a and 9b in the respective rows. A speed difference is obtained and calculated based on a ratio between this difference and the rotational speed of the hub 2 detected by the rotational speed detection sensor 15a. This point will be described with reference to FIG. In the following description, it is assumed that the contact angles α _a and α _b of the rolling elements 9 a and 9 b in each row are the same in a state where the axial load F _a is not applied.

FIG. 9 schematically shows the rolling bearing unit for supporting the wheel shown in FIG. 1 and shows the action state of the load. Preloads F ₀ and F ₀ are applied to the rolling elements 9 a and 9 b arranged in a double row between the double row inner ring raceways 8 and 8 and the double row outer ring raceways 7 and 7. Further, a radial load F _r is applied to the rolling bearing unit during use due to the weight of the vehicle body or the like. Further, by the centrifugal force or the like applied during cornering, applied is the axial load F _a. These preloads F ₀ , F ₀ , radial load F _r , and axial load F _a all affect the contact angles α (α _a , α _b ) of the rolling elements 9a, 9b. Then, the contact angle alpha _a, the alpha _b is changed, these rolling elements 9a, the revolution speed n _c of 9b changes. The diameter of the pitch circle of each of these rolling elements 9a, 9b is D, the diameter of each of these rolling elements 9a, 9b is d, the rotational speed of the hub 2 provided with each of the inner ring raceways 8, 8 is n _i , When the rotational speed of the outer race 1 provided with the outer ring raceway 7, 7 and 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 9a, the revolution speed n _c of 9b, these rolling elements 9a, the contact angle α (α _a, α _b) of 9b varies in response to changes in As described above, the contact angles α _a and α _b change according to the radial load F _r and the axial load F _a . Thus the revolution speed n _c is changed according to these radial load F _r and axial load F _a. In this example, since the hub 2 rotates and the outer ring 1 does not rotate, specifically, as the radial load F _r increases, the revolution speed nc _decreases . Further, with respect to the axial load F _a, the revolution speed of the column that supports the axial load F _a faster, revolution speeds of the columns that do not support this axial load F _a is delayed. Therefore, the radial load F _r and the axial load F _a can be obtained based on the revolution speed n _c .

However, the contact angle α which leads to a change in the revolution speed n _c, as well as the radial load F _r and the axial load F _a is changed while associated with each other, also varies the preload F _0, F ₀ To do. Also, the revolution speed n _c is changed in proportion to the rotational speed n _i of the hub 2. Therefore, if the radial load F _r , the axial load F _a , the preload F ₀ , F ₀ , and the rotational speed n _i of the hub 2 are not considered in total, it is possible to accurately obtain the revolution speed n _c. Can not. Of these, the preloads F ₀ and F ₀ do not change according to the operating state, so it is easy to eliminate the influence by initial setting or the like. On the other hand, the radial load F _r , the axial load F _a , and the rotational speed n _i of the hub 2 constantly change according to the operating state, so that the influence cannot be eliminated by initial setting or the like.

In the case of the present embodiment in view of such circumstances, as described above, when the radial load F _r is obtained, the rolling elements 9a of the respective rows detected by the respective revolution speed detecting sensors 24a, 24b, by obtaining the sum of the revolution speeds of 9b, it is less affected in the axial load F _a. Further, when determining the axial load F _a , the influence of the radial load F _r is reduced by determining the difference in revolution speed between the rolling elements 9 a and 9 b in each row. Further calculation, in any case, and the sum or difference, the ratio to the radial load F _r or the axial load F _a on the basis of the rotational speed n _i of the hub 2 to the rotational speed detecting sensor 15a detects by and by eliminating the influence of the rotational speed n _i of the hub 2. However, the axial load F _a, when calculating on the basis of the rolling elements 9a, 9b ratio of the revolution speed of said each row, the rotational speed n _i of the hub 2 is not necessarily required.

There are various other methods for calculating one or both of the radial load F _r and the axial load F _a based on the signals of the revolution speed detection sensors 24a and 24b. Such a method is described in detail in the above-mentioned Japanese Patent Application Nos. 2003-171715 and 172484, and is not related to the gist of the present invention.
In addition, the above description has been made in the case where an MID board is used as a printed board having a three-dimensional structure for mounting the sensors 24a, 24b, and 15a. A metal base board is used as the printed board. In this case, the same configuration can be used.

  FIG. 10 shows a second embodiment of the present invention. In the case of the present embodiment, the shape of the mounting flange 35a provided on the holder 33a is different from that of the first embodiment described above, and only one through hole 38a for inserting the mounting screw is formed. Other configurations and operations are the same as those in the first embodiment described above, and thus illustrations and descriptions relating to equivalent parts are omitted.

  FIG. 11 shows Embodiment 3 of the present invention. In the case of the present embodiment, among the pair of substrate portions 29a and 29b provided in parallel to each other, through holes 31 for inserting the ends of the conductors of the harnesses 32 and 32 (see FIGS. 5 and 6), One substrate part 29b (on the right side in FIG. 11) forming 31 is made longer than the other substrate part 29a. And each said through-hole 31, 31 is formed in the part which protruded rather than the said other board | substrate part 29a in the other end part of this one board | substrate part 29b. In the case of such a present Example, the operation | work which penetrates the edge part of the conducting wire of each said harness 32, 32 to each said through-hole 31, 31 from the center side of the MID board | substrate 28a can be performed easily. Other configurations and operations are the same as those of the first embodiment described above, and thus illustrations and explanations of equivalent parts are omitted.

  FIG. 12 shows a fourth embodiment of the present invention. In the case of the present embodiment, as the MID substrate 28b, a pair of substrate portions 29a and 29b are connected to each other by the second connecting portion 40 so that the whole is formed into a square shape. ing. In this way, the MID substrate 28b having a closed shape can have higher rigidity than the MID substrate (see FIG. 4) having an open shape, like the U-shape described above. For this reason, the precision regarding the assembly position of the pair of revolution speed detection sensors 24a and 24b mounted on the MID board 28b can be further improved. Corresponding to the provision of the second connecting portion 40, the through holes 31, 31 for inserting the ends of the conductors of the harnesses 32, 32 (see FIGS. 5 and 6) are connected to the second connecting portion. The unit 40 is provided. Other configurations and operations are the same as those of the first embodiment described above, and thus illustrations and explanations of equivalent parts are omitted.

  FIG. 13 shows a fifth embodiment of the present invention. In the case of the present embodiment, among the pair of substrate portions 29a and 29b provided in parallel to each other, through holes 31 for inserting the ends of the conductors of the harnesses 32 and 32 (see FIGS. 5 and 6), One substrate part 29b (on the right side in FIG. 11) forming 31 is made longer than the other substrate part 29a. And each said through-hole 31, 31 is formed in the part which protruded rather than the said other board | substrate part 29a in the other end part of this one board | substrate part 29b. And the edge part of the 2nd connection part 40 is made to continue to the intermediate part other end part of said one board | substrate part 29b. In the case of such a present Example, the operation | work which penetrates the edge part of the conducting wire of each said harness 32, 32 to each said through-hole 31, 31 from the center side of the MID board | substrate 28b can be performed easily. Since other configurations and operations are the same as those of the above-described fifth embodiment, illustration and description regarding equivalent parts are omitted.

  As is clear from the first to fifth embodiments described above, according to the present invention, a total of three speed detecting sensors, that is, a pair of revolution speed detecting sensors 24a and 24b and a single rotational speed detecting sensor 15a. As described above, it is possible to improve the efficiency of the assembly work while ensuring the efficient arrangement of the plurality of sensors and the positional accuracy. However, in the structure of each of the above embodiments, as is apparent from the description made with reference to FIGS. 5 and 6, the output signals of the sensors 24a, 24b, and 15a are respectively transmitted by the dedicated harnesses 32 and 32, respectively. The data is sent to a calculator (not shown). On the other hand, the output signals of the sensors 24a, 24b, and 15a are combined (superimposed) and sent to the arithmetic unit using a single harness, and the arithmetic unit outputs the output signals of the sensors 24a, 24b, and 15a. If separated, the number of harnesses used can be reduced. The cost can be reduced by reducing the material cost and the number of assembling steps, and the driving performance of the automobile can be improved by reducing the weight, focusing on the driving stability and the fuel efficiency.

  2. Description of the Related Art Conventionally, a technique for performing modulation and demodulation, such as FM waves, is known as a technique for transmitting a plurality of signals in a superimposed manner and separating them on the receiving side. However, it is not practical to incorporate a modulator in a part where the installation space is extremely limited, such as the sensor unit 22 (FIGS. 1 and 2) incorporated in a rolling bearing unit for supporting a wheel of an automobile. Therefore, the output signals of the sensors 24a, 24b, and 15a are combined (superimposed) in a limited installation space such as the sensor unit 22 and sent to the arithmetic unit using a single harness. As a method of separating the output signals of the sensors 24a, 24b, and 15a, the following method is conceivable.

  That is, as shown in FIG. 14, the output signals of the sensors 24a, 24b, and 15a are caused by voltage (digital) changes, and the output signals of the sensors 24a, 24b, and 15a are synthesized by the adder circuit 41. Then, it is sent as a single signal to one harness 32a and sent to the above-mentioned computing unit on the receiving side. On the arithmetic unit side, the synthesized signal is returned to the original output signal of each of the sensors 24a, 24b, 15a by the separation circuit (demodulation circuit) 42. As described above, when the signal output of each of the sensors 24a, 24b, and 15a is synthesized by the adder circuit 41, if the voltage level of the signal output of each of the sensors 24a, 24b, and 15a is appropriately changed, synthesis is performed. The original output signal can be extracted from the connected signal.

As a sensor unit 22 incorporated in a rolling bearing unit for supporting a wheel of an automobile, it is expressed as a change in voltage while considering installation in a limited space (which cannot incorporate extra equipment such as a step-up transformer). After synthesizing a plurality of types of output signals (three types in the case of the embodiment), the sensors 24a, 24b, and 15a can be separated into the original output signal. It is necessary to regulate the output voltage so that both of the following conditions (a) and (b) are satisfied.
(a) The total value of one or more types of voltages selected from the plurality of types of output signals is different from each other regardless of which combination is adopted.
(b) The total output voltage of each of the sensors 24a, 24b, 15a is less than or equal to the supply voltage.

  Consider the combination of the output voltages of the sensors 24a, 24b, and 15a under these conditions. Regarding the above (b), for example, the supply voltage of a general passenger car is 12V of the battery, and it is necessary to consider that the voltage drops to about 9V in some cases. Under such conditions, the output voltage (A output) of one revolution speed detecting sensor 24a is set to 2V, the output voltage (B output) of the other revolution speed detecting sensor 24b is set to 3V, and a rotational speed detecting sensor is used. It is conceivable that the output voltage (C output) of the sensor 15a is set to 4V. When the output voltages of the sensors 24a, 24b, and 15a are regulated in this way, the combinations of output signals of the sensors 24a, 24b, and 15a are as shown in Table 1 below. All conditions are met.

  As shown in Table 1, if the combination of output voltages of the sensors 24a, 24b, and 15a is 2V, 3V, and 4V, the outputs of the sensors 24a, 24b, and 15a are combined to form a single harness. After transmission by 32a, it becomes possible to separate (demodulate) the output signals of these sensors 24a, 24b, 15a. Further, since the maximum voltage obtained by adding all the output voltages is 9 V, it can be used in a battery. The combination of the output voltages of the sensors 24a, 24b, and 15a is not limited to the example shown in Table 1 above. In short, all of the above conditions (a) and (b) may be satisfied. However, it is preferable from the standpoint of preventing malfunctions that the output voltages of the sensors 24a, 24b, and 15a and the total value of the one or more types of voltages are as large as possible.

The means for changing the output voltage of each of the sensors 24a, 24b, 15a is not particularly limited. However, when each of the sensors 24a, 24b, 15a is a magnetic detection type sensor, the output is an open collector (drain) output. Considering that there are many cases, it is conceivable to change the voltage connected to the output pull-up resistor. For example, when the supply voltage is 12V, as shown in FIG. 15, the output voltage of each of the sensors 24a, 24b, and 15a can be changed by the voltage dividing ratio by resistance. That is, as shown in FIG. 15, the supply voltage _Vcc of 12V is changed to 1: 2, 1: 3, 1: 5 by resistance (the number before R indicating resistance is the proportional value of the resistance value). The output voltages of the sensors 24a, 24b, and 15a are 4V, 3V, and 2V, respectively. In this case, the supply voltage V _cc fluctuates the sensors 24a, 24b, since the voltage of 15a output signal of varies, (calculator side is the reception side) the supply information signal processing side of the voltage V _cc It is necessary to change the detection voltage setting of the separation circuit (demodulation circuit) 42. Further, in order to change the output voltage of each of the sensors 24a, 24b, 15a, a constant voltage may be generated by a constant voltage regulator, a Zener diode, or the like without using a voltage dividing ratio by a resistor.

FIG. 16 shows an example of the adding circuit 41 for synthesizing the output voltages of the sensors 24a, 24b, and 15a. In this adder circuit 41, the output voltage V _out represented by V _out = V ₁ + V ₂ + V ₃ can be obtained by making the values of the resistors R all the same. Further, by using a single power supply operational amplifier and making it a non-inverting addition circuit, it is possible to use the same single power supply as each of the sensors 24a, 24b and 15a, each of which is a magnetic sensor. Therefore, only one harness is required to supply power to the sensor unit 22 in combination with the adder circuit 41 and the sensors 24a, 24b, and 15a. Examples of combining a plurality of output voltages using such an adder circuit 41 are shown in FIGS. Of these, FIG. 17 shows an example in which two output voltages are combined (added), and FIG. 18 shows an example in which three output voltages are combined (added). The bottom diagram in each figure shows the synthesized signal, and the other diagram shows the single signal. 17 and 18, it can be seen that the synthesized signal leaves a history of each individual signal. The adder circuit for synthesizing the output voltages of the sensors 24a, 24b, and 15a only needs to add a plurality of types (three types in the illustrated example) of different output voltages, as shown in FIG. The structure is not limited.

  Further, FIG. 19 shows an example of the configuration of the separation circuit (demodulation circuit) 42. As shown in Table 1, the separation circuit 42 has a total of seven types of voltages including three types of output voltages related to the three sensors 24a, 24b, and 15a and a total value of four types. The seven comparators A to G are configured to determine (the magnitude relationship with the threshold value set for each comparator). Based on the determination results of the seven comparators A to G, the output voltages are separated into individual output voltages (the A output, the B output, and the C output) related to the sensors 24a, 24b, and 15a. Demodulate to output signal.

  When the outputs of the sensors 24a, 24b, and 15a are 2V, 3V, and 4V, respectively, as described in Table 1, the comparators A to G are configured by window comparators. The voltage values passed by each of the comparators A to G are 1.6 V to 2.4 V for the comparator A, 2.6 V to 3.4 V for the comparator B, and 3.6V to 4.4V for the comparator D, 4.6V to 5.4V for the comparator D, 5.6V to 6.4V for the comparator E, and 6.V for the comparator F. 6V to 7.4V, and the comparator G is set to 8.6V to 9.4V. Further, three OR circuits 43a, 43b, and 43c are connected to the subsequent stage of each of the comparators A to G, and the output voltage that has passed through each of the comparators A to G is used for each of the sensors 24a, 24b, and 15a. Output voltages (A output, B output, C output). Such OR circuits 43a, 43b and 43c are connected to the outputs of the comparators A to G in accordance with the voltages detected and compared by the comparators A to G. Among these, the OR circuit 43a for taking out the A output has comparators A, D, E, and G, and the OR circuit 43b for taking out the B output has comparators B, D, F, G, and C outputs. The OR circuit 43c for taking out is connected to the comparators C, E, F, and G, respectively.

  In other words, for example, the comparator D that passes the signal in which the A output and the B output are summed is connected to the OR circuit 43a corresponding to the A signal and the OR circuit 43b corresponding to the B signal. The comparator E that passes the summed output signal is connected to the OR circuit 43a corresponding to the A signal and the OR circuit 43c corresponding to the C signal. For example, when the A signal and the B signal become HIGH outputs (voltage is high), the output sent from the adder circuit 41 becomes 5V, and the output of the comparator D changes (to HIGH or LOW). The output of the comparator D is sent to the OR circuits 43a and 43b, and the corresponding A signal and B signal change (to HIGH or LOW) and can be demodulated to the original signal. The separation circuit for returning the signal synthesized by the adder circuit 41 to the original signal is not limited to the structure shown in FIG. For example, a digital circuit or a CPU may be used.

The present invention is not limited to the rolling bearing unit load measuring device for measuring the load applied to the rolling bearing unit that supports the wheel of the automobile as shown in each embodiment, but various rotations such as machine tools and industrial machines. It can be used to determine the load acting on the mechanical device.
Further, the invention of combining the detection signals of a plurality of sensors and sending them by one harness and then separating them is carried out in combination with a printed circuit board having a three-dimensional structure. Although it is preferable from the viewpoint of cost reduction, size reduction, and weight reduction, it can be implemented separately from a printed circuit board having a three-dimensional structure.

BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing of the rolling bearing unit incorporating the rotation detection apparatus for load measurement which shows Example 1 of this invention. The A section enlarged view of FIG. FIG. 3 is a schematic diagram showing a cage, rolling elements, an encoder, and a rotation detection sensor as seen from above in FIG. 2. The perspective view of a MID board | substrate. The partial cutaway side view which takes out and shows a sensor unit. The partial cutaway view seen from the right side of FIG. The figure seen from the upper part of FIG. BB sectional drawing of FIG. The schematic diagram of a rolling bearing unit for demonstrating the reason which can measure a load based on rotational speed. The figure similar to FIG. 7 which shows Example 2 of this invention. The perspective view of a MID board | substrate which shows the same Example 3. FIG. The perspective view of a MID board | substrate which shows the same Example 4. FIG. The perspective view of the MID board | substrate which shows the same Example 5. FIG. The block diagram of the apparatus which shows the same Example 6 and sends the output signal of a some sensor collectively. The circuit diagram of the part which changes the output voltage of a some sensor. The circuit diagram of the addition circuit for synthesize | combining the output voltage of a some sensor. The diagram which shows the 1st example of the state which synthesize | combined the output voltage of the some sensor. The diagram which shows the 2nd example. The circuit diagram of the isolation | separation circuit for isolate | separating the signal which synthesize | combined the output voltage of several sensors. Sectional drawing of the rolling bearing unit which incorporated the sensor for radial load measurement known conventionally. Sectional drawing of the rolling bearing unit which incorporated the sensor for axial load measurement conventionally known.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a Outer ring 2, 2a Hub 3, 3a Rotation side flange 4 Hub body 5 Nut 6 Inner ring 7 Outer ring raceway 8 Inner ring raceway 9a, 9b Rolling element 10, 10a Mounting hole 11 Displacement sensor 12 Sensor ring 13 Sensor rotor 14 Cover 15, 15a Rotational speed detection sensor 16 Knuckle 17 Fixed flange 18 Bolt 19 Screw hole 20 Load sensor 21a, 21b Cage 22 Sensor unit 23 Detection unit 24a, 24b Revolution speed detection sensor 25 Rim part 26a, 26b Revolution speed detection encoder 27 Rotating speed detection encoder 28, 28a, 28b MID board 29a, 29b Board part 30 Connection part 31 Through hole 32, 32a Harness 33, 33a Holder 34 Insertion part 35, 35a Mounting flange 36 Extraction part 37 Cable 38, 38a Through 39 flat surface 40 second coupling portion 41 adder circuit 42 separating circuit 43a, 43b, 43c OR circuit

Claims (9)

  A stationary wheel that does not rotate even when in use, a rotating wheel that is arranged concentrically with the stationary wheel and that rotates when in use, and a stationary side track that is formed in a pair on opposite portions of the stationary wheel and the rotating wheel. A plurality of rolling elements provided between the rotation-side tracks, each having a contact angle direction opposite to each other between the pair of rows, and the revolution speed of the rolling members in each row. A pair of revolution speed detection sensors that detect each of them, and a calculator that calculates a load applied between the stationary wheel and the rotating wheel based on a detection signal sent from each of the revolution speed detection sensors. The printed circuit board for mounting the pair of revolution speed detecting sensors has a three-dimensional structure in which a pair of board parts arranged with a space therebetween are connected to each other by a connecting part. Printed circuit board Load measuring device of the gully bearing unit.   The load measuring device for a rolling bearing unit according to claim 1, wherein the three-dimensional printed circuit board is selected from an MID board and a metal base board.   The rolling bearing unit according to any one of claims 1 and 2, wherein the printed circuit board having a three-dimensional structure has a U-shape as a whole by connecting one end edges of a pair of board parts by a connecting part. Load measuring device.   A printed circuit board having a three-dimensional structure connects one end edges of a pair of substrate portions by a connecting portion, and connects the other end edges or intermediate portions of the pair of substrate portions by a second connecting portion. The load measuring device for a rolling bearing unit according to any one of claims 1 and 2, wherein the whole or a part thereof is formed in a square shape.   One of the stationary ring and the rotating ring is an outer ring equivalent member, the other race ring is an inner ring equivalent member, each rolling element is a ball, and the characteristics are alternately changed in the circumferential direction. Further, a pair of revolution speed detecting encoders are supported and fixed concentrically with the respective cages on the mutually opposing side surfaces of the pair of cages holding the balls, and a pair of revolution speed detecting sensors. Is disposed between the pair of revolution speed detection encoders, and the detection portions of the two revolution speed detection sensors are opposed to the mutually opposing side surfaces of the revolution speed detection encoders, A plurality of balls each provided between a double-row angular inner ring raceway formed on the outer peripheral surface of the inner ring equivalent member and a double-row angular outer ring raceway formed on the inner peripheral surface of the outer ring equivalent member. And back combination The contact angle of the mold is applied, the load measuring device of the rolling bearing unit as set forth in claim 1.   The computing unit calculates an axial load applied between the stationary wheel and the rotating wheel based on a ratio between the revolution speed of the rolling elements in one row and the revolution speed in the other row. The load measuring device of the rolling bearing unit described in 1.   The rotational speed of this rotating wheel is set by facing the detection surface of the encoder for detecting the rotational speed, which is installed at the connecting part of the printed circuit board having a three-dimensional structure and fitted and fixed to the middle part of the rotating wheel. Rotation speed detection sensor that can be freely detected, and the computing unit calculates the ratio of the revolution speed of the rolling elements in one row and the revolution speed of the rolling elements in the other row and the rotation speed of the rotating wheel. 6. The load measuring device for a rolling bearing unit according to claim 1, wherein a radial load applied between the stationary wheel and the rotating wheel is calculated based on the load.   The rotational speed of the rotating wheel is set by connecting it to the detection surface of the rotational speed detecting sensor that is installed at the connecting part of the printed circuit board having a three-dimensional structure and fitted and fixed to the intermediate part of the rotating wheel. A rotation speed detection sensor that can be freely detected is provided, and the computing unit calculates the ratio between the revolution speed of the rolling elements in one row and the revolution speed of the rolling elements in the other row and the rotation speed of the rotating wheel. The load measuring device for a rolling bearing unit according to any one of claims 1 to 5, wherein an axial load applied between the stationary wheel and the rotating wheel is calculated on the basis thereof.   An adder circuit that synthesizes the output signals of a plurality of speed detection sensors and sends them to one harness, and a separation circuit that separates the signals sent through the one harness and extracts the output signals of the speed detection sensors. A load measuring device for a rolling bearing unit according to claim 1, comprising a circuit.

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