JP2006307935A - Rolling bearing device with sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing device with a sensor capable of setting pre-load of a rolling bearing easily, inexpensively, and accurately. <P>SOLUTION: A belt-shaped membrane 11 having insulation property is bonded to an outer peripheral face of an outer ring so as to extend in the peripheral direction. A foil 12 composed of four same parts and having electric conductivity is bonded to the membrane 11 so as to be arranged at a substantially equal interval in the peripheral direction of the outer ring. Resistance between a first section and a second section of the foil 12 is measured by a resistance measuring part of a microcomputer. A pre-load calculating part of the microcomputer calculates pre-load of the outer ring based on the measured resistance after receiving output from the resistance measuring part. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sensor-equipped rolling bearing device.

  Conventionally, as a rolling bearing device with a sensor, there is a double row angular contact ball bearing device described in JP-A-2002-213438 (Patent Document 1).

  This double row angular contact ball bearing device has a ball disposed between one of the two rows of raceway grooves formed on the inner circumferential surface of the outer ring and the raceway groove of the first inner race, A ball is disposed between the other of the two rows of raceway grooves and the raceway groove of the second inner ring.

  The first inner ring and the second inner ring are spaced from each other in the axial direction of the bearing device. A groove having a substantially trapezoidal cross section extending in the circumferential direction of the outer ring is formed in an outer peripheral portion of the outer ring facing between the first inner ring and the second inner ring. A pressure sensor is disposed in this groove. The lead wire of the pressure sensor is connected to a sensor output processing device. The sensor output device receives the output from the pressure sensor and measures the preload applied to the outer ring.

  The conventional double-row angular contact ball bearing device adjusts the load applied to the outer ring based on the output of the sensor output device, and adjusts the preload applied to the outer ring to an appropriate value.

  The conventional double-row angular contact ball bearing device has an advantage that the preload is measured after assembling the bearing components, so that it is not necessary to consider the dimensional variation of the bearing components.

  However, the conventional double row angular contact ball bearing device has a problem that it is necessary to consider an error based on the mounting accuracy of the pressure sensor, and the measurement amplifier needs to be adjusted based on the mounting accuracy of the pressure sensor.

In the conventional double-row angular contact ball bearing device, since the sensor is a pressure sensor having a considerable thickness, it is necessary to increase the depth of the groove for accommodating the pressure sensor. There is a problem that the cost is increased and the mounting cost of the pressure sensor is large.
JP 2002-213438 A

  Accordingly, an object of the present invention is to provide a sensor-equipped rolling bearing device that can easily and inexpensively set the preload applied to the rolling bearing.

In order to solve the above problems, a rolling bearing device with a sensor according to the present invention comprises:
An outer ring having a raceway surface on the inner periphery;
An inner ring having a raceway surface on the outer periphery;
A rolling element disposed between the raceway surface of the outer ring and the raceway surface of the inner ring;
Affixed to the surface of the outer ring or the inner ring, an insulating film, affixed on the film, and a conductive foil, between the first location and the second location of the foil And a sensor having a measurement unit for measuring current, voltage, or resistance.

  Here, the foil is obtained by thinning a metal such as gold, silver, copper or tin. A piece of paper-like metal that sticks to the surface of an object.

  According to the present invention, an insulating film affixed to the surface of the outer ring or the inner ring, a conductive foil attached on the film, and between the first location and the second location of the foil Since it has a sensor having a measuring part for measuring current, voltage or resistance, by measuring the current, voltage or resistance between the first place and the second place of the foil in the measuring part, The strain of the foil that correlates with this current, voltage or resistance can be measured, and based on the strain of this foil, the strain of the outer ring or inner ring to which the foil is attached (stress acting on the outer ring or inner ring) Can be detected and the applied preload can be measured.

  Further, according to the present invention, since the portion attached to the bearing in the sensor is a film and foil having a uniform thickness and extremely thin thickness, the depth of the groove formed on the surface of the outer ring or the inner ring is reduced. The preload applied to the outer ring or the inner ring can be measured simply by attaching a film and a foil to the groove having a shallow depth. Therefore, the preload can be measured easily and inexpensively.

  In addition, according to the present invention, the portion of the sensor that is attached to the bearing is made of a film and foil that are uniform and extremely thin and have flexibility, so that the sensor can be easily bent even on a curved surface. Can be pasted. Moreover, after attaching a sensor to a bearing, it can suppress that the thickness of the part attached to the bearing in a sensor changes depending on the shape of the bearing part to which the part was attached. Therefore, almost no error occurs when the sensor is attached, and the degree of measurement of the preload can be improved.

  Moreover, the rolling bearing apparatus with a sensor of one Embodiment is the strip | belt shape where the said foil meandered.

  According to the embodiment, since the foil has a meandering belt shape whose electrical characteristics are likely to change due to strain, distortion of the outer ring or inner ring and preload acting on the outer ring or inner ring can be accurately measured. .

  Further, in the rolling bearing device with a sensor according to one embodiment, the film is attached to the outer peripheral surface of the outer ring, and the foil is arranged on the outer periphery of the outer ring at substantially equal intervals in the circumferential direction of the outer ring. It consists of a plurality of parts of the same shape.

  According to the above embodiment, since the foil is composed of a plurality of parts having the same shape arranged at substantially equal intervals in the circumferential direction of the outer ring on the outer periphery of the outer ring, it is not a local distortion of the outer ring. The average distortion of the entire outer ring can be measured.

  In one embodiment of the rolling bearing device with sensor, the material of the film is a polyimide-based material, and the material of the foil is nichrome.

  According to the embodiment, since the material of the film is a polyimide material, a thin film having excellent insulating properties can be formed. Further, since the material of the foil is nichrome, it is possible to form a foil that is thin and can easily detect a change in current, voltage, or resistance in response to strain.

  Moreover, the rolling bearing device with a sensor of one Embodiment is provided with the preload calculation part which calculates the preload provided to the said outer ring | wheel or an inner ring | wheel based on the output from the said measurement part.

  According to the embodiment, since the preload calculation unit that calculates the preload applied to the outer ring or the inner ring based on the output from the measurement unit is provided, the preload applied to the outer ring or the inner ring can be calculated. .

  According to the rolling bearing device with a sensor of the present invention, the current, voltage, or resistance between the first location and the second location of the foil is measured by the measurement unit, so that there is a correlation with the current, voltage, or resistance. The strain of a certain foil can be measured, and the preload applied to the outer ring or the inner ring can be measured based on the strain of the foil.

  Further, according to the rolling bearing device with a sensor of the present invention, it is not necessary to form a groove for accommodating the pressure sensor in the outer ring or the inner ring, and a groove having a shallow depth is formed in the outer ring or the inner ring. The preload applied to the outer ring or the inner ring can be measured simply by attaching a film and a foil to the inner ring, and the preload can be measured easily and inexpensively.

  Further, according to the rolling bearing device with a sensor of the present invention, the pressure sensor is not attached to the outer ring, but a thin film and foil are attached to the outer ring or the inner ring. The preload can be accurately measured with little occurrence.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a sectional view in the axial direction of a double-row angular contact ball bearing device which is an embodiment of a rolling bearing device with a sensor according to the present invention.

  This double-row angular ball bearing device includes an outer ring 1, a first inner ring 2, a second inner ring 3, a ball 4 as an example of a rolling element, and a sensor 5. The first inner ring 2 and the second inner ring 3 are spaced from each other in the axial direction of the outer ring 1.

  The outer ring 1 has two rows of first track grooves and second track grooves as an example of a raceway surface on the inner periphery, while the first inner ring 2 and the second inner ring 3 are on the outer periphery. It has one track groove as an example of the track surface. The outer ring is fitted and fixed to the housing 17, while the first inner ring 2 and the second inner ring 3 are fitted and fixed to the rotary shaft 18.

  An end surface of the first inner ring 2 opposite to the second inner ring 3 is in contact with the step portion 22 of the rotating shaft 18. A screw 19 is formed on the side of the second inner ring 3 opposite to the first inner ring 2 side in the axial direction of the rotating shaft 18. A nut 20 is engaged with the screw 19. One end surface of the nut 20 in the axial direction is in contact with the end surface of the second inner ring 3 opposite to the first inner ring 2 side. By tightening the nut 20, the first and second inner rings 2, 3 are sandwiched in the axial direction between the nut 20 and the step portion 22, and the shafts are connected to the first and second inner rings 2, 3. A load is applied in the direction to apply a preload to the double-row angular contact ball bearing device.

  A plurality of the balls 4 are arranged at a constant interval in the circumferential direction while being held by the first cage 8 between the first raceway groove of the outer ring 1 and the raceway groove of the first inner ring 2. In addition, a plurality of circumferentially spaced intervals are provided between the second raceway groove of the outer ring 1 and the raceway groove of the second inner ring 3 while being held by the second cage 9. .

  The sensor 5 includes a film 11, a foil 12, a microcomputer (hereinafter referred to as a microcomputer) that functions as a resistance measurement unit as an example of a measurement unit, and a function of a preload calculation unit, and an output from the microcomputer. Has a monitor to display the results. In FIG. 1, the thickness of the film 11 and the foil 12 is exaggerated for easy understanding. The film 11 is made of an insulating polyimide material. The film 11 has a band shape. The film 11 is attached to the portion of the outer peripheral surface of the outer ring 1 facing the first inner ring 2 and the second inner ring 3 with an adhesive so as to extend in the circumferential direction of the outer ring 1. Yes. A foil 12 is adhered on the film 11 with an adhesive.

  FIG. 2 is a diagram showing the connection between the microcomputer 28 and the monitor 29 in the double-row angular contact ball bearing device of the embodiment. In FIG. 2, the thickness of the film 11 and the foil 12 is exaggerated for easy understanding.

  As shown in FIG. 2, the foil 12 is electrically connected to the microcomputer 28. The monitor 29 is electrically connected to the microcomputer 28. The microcomputer 28 applies a voltage between the first location and the second location on the foil 12 to measure the resistance between the first location and the second location. Further, the microcomputer measures the strain of the foil 12 (stress acting on the foil 12) based on this resistance, and calculates the preload applied to the outer ring 1 having a correlation with the strain of the foil 12. It is like that. The monitor 29 displays the preload calculated by the microcomputer 28.

  Since the preload applied to the outer ring 1 and the preload applied to the sensor-equipped rolling bearing device have a correlation, the correlation is applied to the outer ring 1 by inputting this correlation into the memory of the microcomputer 28 in advance. By calculating the applied preload, the preload applied to the sensor-equipped rolling bearing device can be easily calculated (in other embodiments, when a film and a foil are attached to the inner ring) The same holds true for the above).

  FIG. 3 is a view showing the film 11 and the foil 12 before being attached to the outer ring 1, and is a view showing the layout of the foil 12 on the film 11.

  As shown in FIG. 3, the film 11 has a band shape. The length in the longitudinal direction of the film 11 is substantially equal to the length in the circumferential direction of the outer peripheral surface of the outer ring 1 to which the film 11 is attached. The foil 12 includes four substantially identical portions, that is, a first portion 31, a second portion 32, a third portion 33, and a fourth portion 34. These four portions are arranged at approximately equal intervals in the longitudinal direction of the film 11 in the order of the first portion 31, the second portion 32, the third portion 33, and the fourth portion 34 from one end of the film 11. With the film 11 attached to the outer ring 1, the first part 31, the second part 32, the third part 33, and the fourth part 34 are arranged at substantially equal intervals in the circumferential direction of the outer ring 1. ing.

  As shown in FIG. 3, each of the four parts has a shape in which two protruding parts protrude from a rectangular part. One protrusion of the first part 31 and one protrusion of the second part 32 are electrically connected by wiring, and the other protrusion of the second part 32 and one protrusion of the third part 33 are electrically connected by wiring. Has been. Further, the other protrusion of the third portion 33 and one protrusion of the fourth portion 34 are electrically connected by wiring, and the other protrusion of the fourth portion 34 and the other protrusion of the first portion 31 are wiring. Electrical connection.

  One end of the wiring 36 is connected to a node between the other protruding portion of the second portion 32 and one protruding portion of the third portion 33, and the other protruding portion of the fourth portion 34 and the first portion 31 are connected. One end of the wiring 37 is connected to the node between the other protruding portion of the wiring 37. The other end of the wiring 36 is connected to a first terminal of a microcomputer (not shown in FIG. 3), and the other end of the wiring 37 is connected to a second terminal of the microcomputer.

  The other protruding portion of the second portion 32 and the one protruding portion of the third portion 33 are the first portion of the foil 12. Further, the other protrusion of the fourth portion 34 and the other protrusion of the first portion 31 are the second location of the foil 12.

  A structure including the film 11, the foil 12, and the wiring shown in FIG. 3 is manufactured as follows.

  First, a film 11 and a foil 12 having a surface shape substantially the same as that of the film 11 are prepared, and the foil 12 is pasted on the film 11 with an adhesive. The thickness of the foil is preferably 0.005 to 0.03 mm, more preferably 0.008 to 0.015 mm. Thereafter, portions of the foil 12 other than the first, second, third, and fourth portions 31, 32, 33, 34 are etched to form the first, second, third, and fourth on the film 11. A structure in which parts are arranged at equal intervals is manufactured. Finally, a conductive wire having negligible resistance is pasted on the film 11 to form a wiring, and the structure shown in FIG. 3 is manufactured.

  FIG. 4 is a diagram showing the structure of the first portion 31 in detail. Although not described, the second portion 32, the third portion 33, and the fourth portion 34 illustrated in FIG. 3 have the same structure as the first portion 31.

  As shown in FIG. 4, the 1st part 31 has the shape which repeated the linear part and the bending part which changes a direction 180 degree | times alternately. In other words, the first portion 31 has a shape in which a plurality of S-shaped bands are connected and has a meandering band shape. The straight portions other than the straight portion closest to both ends of the meandering band have the same thickness and length. Also, the straight line portion closest to both ends of the meandering band is thicker and longer than the straight line portion other than the straight line portion closest to the both ends. Wiring is connected to both ends of the band.

  FIG. 5 is a diagram showing an equivalent circuit of the foil 12 and the resistance measurement unit.

  In FIG. 5, 31 indicates a first portion of the foil 12, and 32 indicates a second portion of the foil 12. Reference numeral 33 denotes a third portion of the foil 12, and reference numeral 34 denotes a fourth portion of the foil 12. In FIG. 5, 51 indicates a first terminal of the microcomputer 28, and 52 indicates a second terminal of the microcomputer 28.

  As shown in FIG. 5, the resistors 56, 57, and 58 built in the microcomputer 28 are directly connected between the first portion 60 of the foil 12 and the second portion 61 of the foil 12. Yes.

  Further, the microcomputer 30 applies a voltage E to both ends of the resistor 57 and the resistor 58 that are directly connected, and measures the voltage e across the resistor 56 and the resistor 57 that are directly connected. The resistance between the first location 60 and the second location 61 of the foil 12 is measured.

  In this embodiment, as shown in FIG. 5, the first part 31 and the second part 32 connected in series and the third part 33 and the fourth part 34 connected in series are connected in parallel. Therefore, the average resistance value of the resistance of the first portion 31, the resistance of the second portion 32, the resistance of the third portion 33 and the resistance of the fourth portion 34 can be measured, and the preload acting on the outer ring 1 can be measured. Can be measured globally and accurately rather than locally.

  According to the rolling bearing device with sensor of the above embodiment, the insulating film 11 attached to the surface of the outer ring 1, the conductive foil 12 attached on the film 11, and the first portion 60 of the foil 12. Since the microcomputer 28 for measuring the resistance between the first location 60 and the second location 61 is included, by measuring the resistance between the first location 60 and the second location 61 of the foil 12 with the microcomputer 28, The strain of the foil 12 having a correlation with the measured resistance can be measured, and the preload applied to the outer ring 1 can be measured based on the strain of the foil 12.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, since the part attached to the outer ring | wheel 1 in the sensor is the film | membrane 11 and foil 12 with uniform thickness and very thin, on the surface of the outer ring | wheel 1 Since the depth of the groove to be formed can be remarkably reduced as compared with the conventional case, the groove processing cost can be reduced. Further, the preload applied to the outer ring 1 can be measured simply by attaching the film 11 and the foil 12 to the shallow groove. Therefore, the preload can be measured easily and inexpensively.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, the part attached to the outer ring | wheel 1 in the sensor is the film | membrane 11 and foil 12 which are uniform and extremely thin, and have the softness | flexibility. The sensor can be easily attached to the outer peripheral surface of the bent outer ring 1. Moreover, after attaching a sensor to the outer ring | wheel 1, it can suppress that the thickness of the part attached to the outer ring | wheel 1 in a sensor changes depending on the shape of the outer ring | wheel 1 part to which the part was attached. Therefore, almost no error occurs when the sensor is attached, and the degree of measurement of the preload can be improved.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, since the foil 12 is the meandering belt | band | zone shape where an electrical characteristic is easy to change with distortion, it acts on the distortion of the outer ring 1, and the outer ring 1. Preload can be measured accurately.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, the said foil 12 consists of four parts of the same shape, and these four parts are substantially equal intervals on the outer periphery of the outer ring 1 in the circumferential direction of the outer ring 1. Therefore, the average distortion of the entire outer ring 1 can be measured, not the local distortion of the outer ring 1.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, since the material of the said film | membrane 11 is a polyimide-type material, the film | membrane 11 which is thin and excellent in insulation can be formed. Further, since the material of the foil 12 is nichrome, it is possible to form the foil 12 which is thin and can easily detect the resistance variation corresponding to the strain.

  Moreover, according to the rolling bearing device with a sensor of the said embodiment, since it has in the microcomputer 28 the preload calculation part which calculates the preload provided to the outer ring | wheel 1 based on the output from the measurement part of the microcomputer 28, The preload applied to the outer ring 1 can be calculated.

  In the rolling bearing device with a sensor according to the above embodiment, the foil 12 having substantially the same shape as that of the film 11 is pasted on the film 11, and then an excess portion of the foil 12 is etched to form a sensor. In the present invention, the sensor may be formed by attaching a foil previously formed in a predetermined shape on the film.

  Moreover, in the rolling bearing device with a sensor of the said embodiment, although the film | membrane 11 was made into strip | belt shape and it was affixed over the perimeter of the circumferential direction of the outer ring | wheel 1, in this invention, a film | membrane is foil and a preload. It is only necessary to be arranged between the bearing ring (outer ring or inner ring) to be measured and it is not necessary to be arranged over the entire circumference of the bearing ring.

  Moreover, in the rolling bearing device with a sensor of the said embodiment, although resistance between the 1st location 60 of the foil 12 and the 2nd location 61 was measured and distortion of the foil 12 was measured based on this measurement, In the invention, the current or voltage between the first location and the second location of the foil may be measured, and the strain of the foil may be measured based on the measured current or voltage.

  Moreover, in the rolling bearing device with a sensor of the said embodiment, the 1st part 31 and the 2nd part 32 which were connected in series, and the 3rd part 33 and the 4th part 34 which were connected in series were connected in parallel. However, in the present invention, the foil may be composed of a plurality of portions, and the current, voltage, or resistance of each of the plurality of portions may be measured independently, and then the average of the plurality of values may be calculated. . In this case, of course, the foil has a plurality of first locations and a plurality of second locations.

  Moreover, in the rolling bearing device with a sensor of the said embodiment, although the foil 12 consisted of four parts discretely arrange | positioned at the outer ring | wheel 1, in this invention, foil was discretely arrange | positioned at the outer ring | wheel. The foil may consist of a plurality of parts other than four, and the foil may consist of one part.

  Moreover, in the rolling bearing device with a sensor of the said embodiment, although the film | membrane 11 was formed from the polyimide-type material, in this invention, it has insulation other than polyimide-type materials, such as a polyester-type material, for example. You may form from a material. Moreover, you may form foil from materials which have electroconductivity other than nichrome. For example, Ni may be used, and Cu may be adjusted to optimize the cross-sectional area.

  Moreover, in the rolling bearing device with a sensor of the said embodiment, although the film | membrane 11 and foil 12 were affixed on the outer ring | wheel 1, in this invention, you may affix a film | membrane and foil on an inner ring | wheel.

  In the above embodiment, the sensor having the film 11 and the foil 12 is attached to the double-row angular contact ball bearing. However, in the present invention, the sensor having the film and the foil is combined with a deep groove ball bearing or a roller bearing. The sensor-equipped rolling bearing device may be configured by being attached to a rolling bearing other than the row angular ball bearing.

It is sectional drawing of the axial direction of the double row angular contact ball bearing apparatus which is one Embodiment of the rolling bearing apparatus with a sensor of this invention. It is a figure which shows the connection of the microcomputer and monitor with which the double row angular contact ball bearing apparatus of the said embodiment is provided. It is a figure which shows the layout of the foil on a film | membrane. It is a figure which shows the structure of the 1st part of foil in detail. It is a figure which shows the equivalent circuit of foil and the resistance measurement part of a microcomputer.

Explanation of symbols

1 outer ring 2 first inner ring 3 second inner ring 4 ball 5 sensor 11 film 12 foil 28 microcomputer 31 first part 32 second part 33 third part 34 fourth part 60 first part 61 second part

Claims (5)

An outer ring having a raceway surface on the inner periphery;
An inner ring having a raceway surface on the outer periphery;
A rolling element disposed between the raceway surface of the outer ring and the raceway surface of the inner ring;
Affixed to the surface of the outer ring or the inner ring, an insulating film, affixed on the film, and a conductive foil, between the first location and the second location of the foil A sensor-equipped rolling bearing device comprising: a sensor having a measurement unit that measures current, voltage, or resistance. In the rolling bearing device with a sensor according to claim 1,
A rolling bearing device with a sensor, wherein the foil has a meandering belt shape. In the rolling bearing device with a sensor according to claim 1 or 2,
The membrane is attached to the outer peripheral surface of the outer ring,
The rolling bearing device with a sensor, wherein the foil is composed of a plurality of portions having the same shape arranged at substantially equal intervals in the circumferential direction of the outer ring on the outer periphery of the outer ring. In the rolling bearing device with a sensor according to any one of claims 1 to 3,
A rolling bearing device with a sensor, wherein the material of the film is a polyimide material, and the material of the foil is nichrome. In the rolling bearing device with a sensor according to any one of claims 1 to 4,
A sensor-equipped rolling bearing device, comprising: a preload calculation unit that calculates a preload applied to the outer ring or the inner ring based on an output from the measurement unit.

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