JP6581423B2 - Anomaly detection device for rolling bearings - Google Patents

Description

  The present invention relates to an abnormality detection device for an oil lubricated rolling bearing.

  Rolling bearings are incorporated in movable parts of transportation equipment, industrial machinery, and other various equipment. In such a device, there is an operation mechanism portion that requires lubrication in addition to the oil-lubricated rolling bearing, and the operation mechanism portion and the rolling bearing have a structure that is lubricated with a common oil. There is something. As an operation mechanism part, the meshing part of gears, the sliding contact part of members, etc. are mentioned, for example.

  For example, an oil pump or the like has a rolling bearing and an operating mechanism part inside the device. In particular, the oil pump has a function of feeding the internal lubricating oil toward another operating mechanism portion outside the device including the rolling bearing and the operating mechanism portion.

  Incidentally, foreign matter such as wear powder (iron powder or the like) may be generated from the bearing space of the rolling bearing. If the foreign matter enters the operating mechanism part in the middle of the lubricating oil circulation path, the durability of the device may be reduced due to the biting of the foreign matter. In some cases, it may lead to malfunction / failure / damage of the equipment.

  Therefore, for example, in Patent Document 1, when a foreign matter made of iron powder or the like is mixed in the lubricating oil flowing in the circulation path, the foreign matter is attracted to a magnet provided in the sensor, and the attracted foreign matter is accumulated. Thus, there is disclosed a method for detecting iron powder contamination of lubricating oil that issues an alarm when a metal casing and a magnet are electrically connected (see, for example, Patent Document 1).

JP 7-280180 A

  As described above, it is not preferable for foreign matter such as wear powder (iron powder or the like) generated from the rolling bearing to enter the operating mechanism portion in the middle of the lubricating oil circulation path. In particular, in a rolling bearing for an oil pump, a large peeling piece generated from the bearing is a part of the operating mechanism part of the oil pump itself or other operating mechanism part in the circulation path of the lubricating oil sent out by the oil pump. May cause malfunction, failure or damage. For this reason, it is necessary to prevent the foreign matter from flowing out of the rolling bearing and to detect the foreign matter when the foreign matter is generated.

  In the technique described in Patent Document 1, the magnet included in the sensor faces the lubricating oil circulation path. However, in this technique, most of the foreign matters contained in the lubricating oil in the circulation path may pass by without being attracted to the magnet of the sensor. Further, in the technique described in Patent Document 1, the trapping of the foreign matter is limited to the minimum amount necessary for detecting the degree of the foreign matter mixed in the lubricating oil, and as a result, the remaining foreign matter is applied to the operating mechanism unit. There is also the problem that intrusion cannot be prevented.

  Accordingly, an object of the present invention is to more reliably prevent foreign matter such as wear powder (iron powder or the like) generated from a rolling bearing from entering an operating mechanism portion in the middle of a lubricating oil circulation path. is there.

  In order to solve the above-described problems, the present invention allows an inner ring and an outer ring, a rolling element disposed in a bearing space between the inner ring and the outer ring, and passage of lubricating oil from the bearing space. A filter for preventing the passage of a metal piece, a pair of permanent magnets provided on the filter and spaced apart from each other, and an electric power extending from both electrodes to the power source by using the pair of permanent magnets as electrodes. A circuit, and an output detection device that detects a state of the metal piece contained in the lubricating oil by detecting a change in electrical output of the electric circuit accompanying the attachment of the metal piece between the pair of permanent magnets. A rolling bearing abnormality detection device was adopted.

  At this time, it is possible to employ a configuration in which a magnetic material is disposed between the pair of permanent magnets via a gap.

  Moreover, the said filter is provided with the through-hole for lubricating oil distribution | circulation, and the structure which the said permanent magnet of a pair is arrange | positioned on both sides across the said through-hole can be employ | adopted.

    In each of these configurations, it is possible to adopt a configuration in which the electrical output detected by the output detection device is a voltage-divided output of the voltage in the electrical circuit.

    In each of these configurations, it is possible to employ a configuration in which a plurality of pairs of electrodes made of the pair of permanent magnets are arranged and the gaps between the electrodes are different from each other.

    Further, in each of these configurations, the pair of permanent magnets has an electrically conductive coating layer on the surface thereof, and the coating layer and a circuit board terminal constituting a part of the electric circuit are electrically connected. It is possible to adopt a configuration that is used.

    The output detection device may employ a configuration for determining an abnormal state based on an electrical output and a predetermined threshold.

    Data storage means (data storage server) for storing information determined by the output detection device to be in an abnormal state, and past change information stored in the data storage means for confirming a temporal change in the abnormal state The structure provided with a means is employable.

  According to the present invention, a pair of permanent magnets spaced apart from each other are provided on a filter that allows passage of lubricating oil from inside the bearing space of the rolling bearing to the outside of the bearing space and prevents passage of metal pieces. Detecting a change in electrical output of the electric circuit due to adhesion of a metal piece between the pair of permanent magnets, and an electric circuit extending from both electrodes to the power source with the pair of permanent magnets as electrodes. And an output detection device that detects the state of the metal pieces contained in the lubricating oil.For this reason, foreign matter such as iron powder and peeling pieces generated from the rolling bearings is placed on the operating mechanism in the middle of the lubricating oil circulation path. Intrusion can be prevented more reliably, and an abnormality of the rolling bearing can be detected by an electrical change, so that failure of each component can be prevented in advance.

1 shows an embodiment of the present invention, (a) is a side view in which a filter is attached to a bearing unit having a plurality of rolling bearings, and (b) is a longitudinal sectional view. The main part of a filter is shown, (a) is a side view when sensor output is one system, and (b) is a side view when sensor output is three systems. Main part enlarged view showing an example in which a magnetic material is arranged between electrodes made of permanent magnets, showing a case where the sensor output is three systems. Schematic cross-sectional view of substrate and electrode showing model of iron powder adsorption state A graph showing the electrical output when the sensor output is one system Graph diagram showing electrical output when sensor output is 3 systems (A) is an electric circuit diagram when the sensor output is one system, (b) is an electric circuit diagram when the sensor output is three systems.

  Embodiments of the present invention will be described with reference to the drawings. This embodiment is an oil pump device 10 including an abnormality detection device for a rolling bearing.

  The oil pump device 10 includes a bearing unit 20 having a plurality of rolling bearings inside the device, and an oil pump operating mechanism 30.

  The bearing unit 20 includes three rolling bearings 21, 22, and 23 that are oil-lubricated in parallel inside the housing 11. By these rolling bearings 21, 22, and 23, a shaft member 32 that communicates with the operating mechanism portion 30 of the oil pump is supported so as to be rotatable about the axis with respect to the fixed housing 11.

  In each of the rolling bearings 21, 22, and 23, a rolling element 3 is incorporated between the raceway surfaces 1 a and 2 a of the outer raceway ring 1 and the inner raceway ring 2. The rolling element 3 is held in the circumferential direction by a cage 4. Hereinafter, the outer race 1 is referred to as an outer race 1 and the inner race 2 is referred to as an inner race 2.

  The outer ring 1 is press-fitted into the inner diameter surface of the housing 11 and fixed to the housing 11 so as not to rotate relative to the housing 11. The inner ring 2 is press-fitted into the outer periphery of the shaft member 32 and is fixed to the shaft member 32 so as not to rotate relative to the shaft member 32.

  In this embodiment, as the rolling bearings 21, 22, and 23, tapered roller bearings using tapered rollers are employed as the rolling elements 3, but rolling bearings other than tapered roller bearings may be employed. The parallel number of the rolling bearings 21, 22, and 23 can be freely set according to the specifications of the apparatus.

  The oil pump operating mechanism 30 includes a pump rotor (not shown) that feeds lubricating oil to the circulation path by rotating relative to each other in the pump casing. The pump rotor is connected to the connection member 31 provided at the end of the shaft member 32, and is thus rotatable around the shaft of the shaft member 32. The driving force to the rotor is input by a separate route from a driving source (not shown).

  As shown in FIG. 1, two rolling bearings 21, 22 near one side of the rolling mechanism 21, 22, 23 in parallel, that is, closer to the operating mechanism portion 30, have smaller diameter side end surfaces of the tapered rollers in the axial direction. Are arranged so as to be on the same side, that is, on the opposite side of the operating mechanism portion 30.

  The rolling bearings 23, 22, 23 arranged in parallel to each other in the axial direction, that is, the rolling bearing 23 farthest from the operating mechanism portion 30 is arranged so that the end surface on the small diameter side of the tapered roller is on the operating mechanism portion 30 side. ing. That is, the rolling bearings 21 and 22 and the rolling bearing 23 are disposed so that the small diameter side end surfaces of the tapered rollers are back to back. For this reason, the raceway surface 2a of the inner ring 2 and the raceway surface 1a of the outer ring 1 are such that two on one side of the three rows of rolling bearings 21, 22, 23 are mutually opposite from one side in the axial direction toward the other side. The distance is reduced, and one of the other sides is provided so that the distance from each other increases from one side in the axial direction to the other side.

  As shown in FIG. 1, spacers 5, 6, 7 are arranged between the rolling bearings 21, 22, 23 adjacent in the axial direction.

  Between the two rolling bearings 21, 22 on the one side in the axial direction of the rolling bearings 21, 22, 23 that are arranged in parallel, a spacer 5 that is in contact with the end faces of the inner rings 2, 2 on both sides is provided on the inner diameter side. On the side, a spacer 6 is disposed that contacts the end faces of the outer rings 1 and 1 on both sides.

  In addition, between the two rolling bearings 22, 23 on the other axial side of the rolling bearings 21, 22, 23 arranged in parallel, a spacer that contacts the end surfaces of the inner rings 2, 2 on both sides is provided on the inner diameter side. A spacer 7 is disposed on the radial side so as to contact the end surfaces of the outer rings 1 and 1 on both sides. In FIG. 1, the inner diameter side spacer between the rolling bearings 22 and 23 is not shown, but along the circumferential direction of the rolling bearings 22 and 23, other than the opening on the outer diameter side of the lubricating oil circulation path 13 b. A spacer is arranged in the portion.

  Both ends of the rolling bearings 21, 22, and 23 that are arranged in parallel are on the one side in the axial direction by the end face of the flange-shaped connection member 31 provided at the end of the shaft member 32, and on the other side in the axial direction, The end face is fixed so as not to move in the axial direction with respect to the shaft member 32. A preload is applied to each tapered roller bearing by fixing the connecting member 31 and the pressing member 8.

  The shaft member 32 supported by the housing 11 by the rolling bearings 21, 22, 23 is connected to the operating mechanism 30 of the oil pump. Further, the oil pump has a function of sending out internal lubricating oil toward another operating mechanism portion outside. The delivered lubricating oil flows along the lubricating oil passage and lubricates the operating mechanism of each part, and then returns to the oil pump.

  In this oil pump, the operating mechanism 30 and the bearing unit 20 in the pump are lubricated with a common lubricating oil. The operating mechanism 30 on the oil pump side and the bearing space on the bearing unit 20 side communicate with each other through circulation paths 12 and 13 for the lubricating oil. The lubricating oil is also sent to an external operating mechanism.

  In this embodiment, the circulation path 13 includes an axial lubrication path 13a provided along the axial direction so as to be concentric with the axis of the shaft member 32 from the oil pump side, and an end of the lubrication path 13a. A radial lubrication path 13b that extends radially outward and opens on the outer peripheral surface of the shaft member 32 is provided. Since the radial lubrication path 13b opens to the annular space C sandwiched between the rolling bearings 22 and 23, the circulation path 13 passes through the annular space C on one side in the axial direction (left side in the figure). Is connected to the bearing spaces of the rolling bearings 21 and 22, and the other axial side (the right side in the figure) is connected to the bearing space of the rolling bearing 23.

  The lubricating oil that has passed through the bearing space of the rolling bearing 23 through the annular space C passes through the opening of the bearing space on the other end side in the axial direction of the rolling bearing 23 and the housing end provided on the other end side in the axial direction of the rolling bearing 23. Enter the subspace B. Thereafter, the oil returns to the operating mechanism 30 side of the oil pump through the lubricating oil circulation passage 12 formed in the housing 11.

  The circulation passage 12 includes a radial lubrication path 12b extending radially outward from the housing end space B, and an axial lubrication path 12a provided along the axial center direction of the shaft member 32 from the radial lubrication path 12b. Prepare.

  Also, the lubricating oil that has passed through the annular space C and the bearing space of the rolling bearings 22 and 21 returns to the operating mechanism portion 30 side of the oil pump through the opening of the bearing space on one end side in the axial direction of the rolling bearing 21. Go.

  Thereby, the operation mechanism part 30 of the oil pump and the rolling bearings 21, 22, and 23 of the bearing unit 20 are lubricated by the common lubricating oil.

  By the way, foreign matter such as wear powder (iron powder or the like) may be generated from the bearing space of the rolling bearings 21, 22, and 23. It is not preferable for this foreign matter to enter the operating mechanism 30 of the oil pump or other operating mechanism in the circulation path. Therefore, a seal ring 40 with a filter F is attached to the opening of the bearing space on one axial end side of the rolling bearing 21 and the opening of the bearing space on the other axial end side of the rolling bearing 23. Both seal rings 40 have a common structure as shown below.

  The seal ring 40 is attached so as to cover the opening on each corresponding side of the bearing space of the rolling bearings 21 and 23. Since the opening is formed in an annular shape along the raceway surfaces 1a and 2a of the outer ring 1 and the inner ring 2, the seal ring 40 covering the opening is also formed in an annular shape.

  In this embodiment, the seal ring 40 is made of a synthetic resin molded product. The resin seal ring 40 is attached between the large collar of the inner ring 2 and the large-diameter side end of the inner diameter surface of the outer ring 1.

  The outer ring 1 is stationary, the inner ring 2 is rotating, and the seal ring 40 is fixed to the outer ring 1 on the fixed side by fitting or the like. The seal ring 40 is fitted to the inner ring 2 on the rotating side. It is also possible to fix by means such as a joint.

  As shown in FIG. 1, the seal ring 40 includes a locking portion 42 that is locked to the outer ring 1, a wall portion 41 that rises from the locking portion 42 toward the inner diameter side, and an inner ring that extends from the wall portion 41. 2 and an inner cylindrical portion 43 facing the outer diameter surface. The locking portion 42 has a cylindrical shape, and the cylindrical locking portion 42 is press-fitted into the inner diameter surface of the outer ring 1. A protrusion or the like provided on the outer diameter surface of the locking portion 42 may be fitted into a seal groove or the like provided on the large diameter side end portion of the inner diameter surface of the outer ring 1 and fixed to each other. The inner cylindrical portion 43 closer to the inner diameter is slidably in contact with the outer surface of the large collar of the inner ring 2 or is opposed through a slight gap.

  A number of through holes 44 are provided in the wall 41 of the seal ring 40. These many through holes 44 prevent foreign substances from passing through the bearing spaces of the rolling bearings 21, 22, and 23, and allow the passage of lubricating oil. The maximum value of the inner diameter of the through-hole 44 is set to an appropriate size so that the passage of foreign matter to the extent that it does not affect even if it enters the operating mechanism 30 side is allowed.

  Inside the filter F of the seal ring 40, a pair of permanent magnets Ma and Mb (51a, 51b; 52a, 52b; 53a, 53b) arranged at intervals are provided. The pair of permanent magnets Ma and Mb are used as electrodes, respectively, and an electric circuit 60 extending from both electrodes to the power source is provided, and a control means 70 for controlling the electric circuit 60 is provided.

  Permanent magnets Ma and Mb and energization wiring connected thereto are installed on the substrate 50. Further, a part of the wiring of the electric circuit 60 is drawn from the substrate to the outside of the rolling bearings 21 and 23, and the drawn out part of the electric circuit 60 and the control means 70 include the housing 11 and its surrounding frame. It is attached to the stationary member.

  The permanent magnets Ma and Mb serve both as the adsorption of foreign matter such as iron powder and iron pieces and the function of the electrode of the electric circuit 60 for detecting it. That is, the permanent magnets Ma and Mb have a magnetic force for adsorbing a metal, and at least the surface thereof has a coating layer (conductive layer) made of a material that conducts electricity. This coating layer and the wiring and terminals of the electric circuit 60 are electrically connected.

  As the material of the permanent magnets Ma and Mb, for example, a material obtained by applying nickel plating (surface treatment) to an Nd system can be used. According to such permanent magnets Ma and Mb, it is possible to solder the wiring to the pattern provided on the substrate 50. Moreover, since nickel plating is excellent in electrical conductivity, the performance of detecting the adsorption of foreign matter is enhanced. As a material for the coating layer provided on the surfaces of the permanent magnets Ma and Mb, plating (surface treatment) of gold, silver, copper or the like may be more suitable. Moreover, you may employ | adopt what the whole raw material of permanent magnet Ma and Mb equips with electrical conductivity.

  As shown in the wiring example of FIG. 2A and the wiring example of FIG. 2B, the permanent magnets Ma and Mb are fixed to the substrate 50 on both sides of the hole 54 provided in the substrate 50. . Since the hole 54 is positioned to match the position of the through hole 44 on the filter F side, the permanent magnets Ma and Mb are disposed on both sides of the through hole 44 for circulating the lubricating oil in the filter F. become. Here, the permanent magnets Ma and Mb are arranged on both sides of the hole 54 along the circumferential direction of the rolling bearing. However, depending on the case, the permanent magnets Ma and Mb are arranged along the radial direction of the rolling bearing. It is good also as a structure arrange | positioned on both sides on both sides of 54.

  The substrate 50 is preferably fixed to the bearing space side of the front and back surfaces of the wall portion 41 of the seal ring 40 from the viewpoint of more efficiently adsorbing foreign matter.

  In addition, as shown in FIG. 3, you may provide magnetic materials 51c, 52c, and 53c, such as a metal and a magnet, between the permanent magnets Ma and Mb. The magnetic materials 51c, 52c, and 53c are disposed between the pair of permanent magnets Ma and Mb with a gap therebetween. A fixed gap is provided between the permanent magnets Ma, Mb and the magnetic materials 51c, 52c, 53c. By providing the magnetic materials 51c, 52c, and 53c, it is possible to enhance the foreign matter adsorption performance as shown in FIG.

  In the wiring example of FIG. 2A, the wiring of the electric circuit 60 has a fixed resistor 59 disposed on the electric circuit 60 of the substrate 50. One end of the fixed resistor 59 is connected to an input terminal (power source) 62 via a wiring 56 formed in a pattern on the substrate 50, and the other end is connected to a wiring 57 formed in a pattern on the substrate 50. ing. The opposite end of the wiring 57 is connected to one permanent magnet Mb. Since one permanent magnet Mb is arranged, the wiring 57 branches from one to three on the way, and each of the branches is connected to each permanent magnet Mb.

  The other permanent magnet Ma is connected to a wiring 58 formed in a pattern on the substrate 50. Since the other permanent magnets Ma are arranged, the wiring 58 branches from one to three on the way, and each of the branched branches is connected to the other permanent magnet Ma. The opposite end of the wiring 58 is connected to the GND terminal 64 as a ground.

  In addition, the wiring 57 branches between a branch portion of three wirings to one permanent magnet Mb and the fixed resistor 59, and the branched wiring is connected to the output terminal 61. The output terminal 61 constitutes a part of the voltage dividing circuit. Thereby, in the wiring example of FIG. 2A, one-system sensor output can be obtained.

  In the wiring example of FIG. 2B, three fixed resistors 59a, 59b, 59c are arranged on the electric circuit 60 of the substrate 50. One end of each fixed resistor 59a, 59b, 59c is connected to an input terminal (power source) 62 via a wiring 56 formed in a pattern on the substrate 50, and the other end is formed in a pattern on the substrate 50, respectively. Connected to the connected wiring 57. Opposite ends of the three wires 57 arranged in parallel are connected to the respective permanent magnets Mb.

  The other permanent magnet Ma is connected to a wiring 58 formed in a pattern on the substrate 50. Since the other permanent magnets Ma are arranged, the wiring 58 branches from one to three on the way, and each of the branched branches is connected to the other permanent magnet Ma. The opposite end of the wiring 58 is connected to the GND terminal 64 as a ground.

  Further, the three wirings 57 arranged in parallel are branched between one permanent magnet Mb and the fixed resistors 59a, 59b, 59c, and the branched wirings are connected to the output terminals 61a, 61b, 61c. The output terminals 61a, 61b, 61c constitute a part of an independent voltage dividing circuit. Thereby, in the wiring example of FIG. 2B, sensor outputs of three systems can be obtained.

  FIG. 7A shows an electric circuit diagram when the sensor output is one system, and FIG. 7B shows an electric circuit diagram when the sensor output is three systems. 7A, the electric resistance of the fixed resistor 59 is R1, and the electric resistance between the pair of permanent magnets 51a, 51b; 52a, 52b; 53a, 53b corresponds to R2 to R4, respectively. 7B, the electric resistances of the fixed resistors 59a to 59c correspond to R1 to R3, and the electric resistances between the pair of permanent magnets 51a and 51b; 52a and 52b; 53a and 53b correspond to R4 to R6, respectively.

  Moreover, the control means 70 controls this electric circuit 60 through the cable 63 drawn out from the input terminal (power supply) 62, the GND terminal 64, the output terminal 61; 61a, 61b, 61c.

  Further, the control means 70 includes an output detection device 71 that detects an output through the voltage dividing circuit of the electric circuit 60. That is, since a change in the electrical output of the electric circuit 60 is detected as a foreign object such as a metal piece adheres between the pair of permanent magnets Ma and Mb, the output detection device 71 detects the electrical output. By acquiring the change, the state of the metal piece contained in the lubricating oil is detected.

  The electrical output detected by the output detection device is a voltage divided output in the electrical circuit. For example, when the potential of the input terminal (power supply) 62 is set to E (V) and the potential of the GND terminal 64 is set to 0 (V), the divided voltage output is obtained between the output terminals 61; 61a, 61b, and 61c positioned therebetween. Indicated by potential.

  Lubricant flows through the bearing space of the rolling bearing and passes through the through hole 44 of the filter F of the seal ring 40. If the lubricating oil contains foreign materials made of materials that adsorb to magnets such as iron powder and peeling pieces (iron pieces), the iron powder and peeling pieces (iron pieces) are attracted to the permanent magnets Ma and Mb and face each other. When the pair of electrodes are electrically short-circuited, the resistance value between the electrodes becomes small.

  Note that the electric resistance value between the permanent magnets Ma and Mb varies depending on the state of adhesion of iron powder or peeled pieces (iron pieces). As a general tendency, the resistance value is large because the cross-sectional area of the portion through which current can pass is small when the amount of adhesion is small, and the resistance value is small because the cross-sectional area of the portion through which current can pass is large when the amount of adhesion is large. Become.

  For example, as shown in FIG. 4A to FIG. 4B, the electrical resistance value between the permanent magnets Ma and Mb decreases as the amount of adsorbed foreign matter increases. That is, the potentials of the output terminals 61; 61a, 61b, 61c are gradually reduced, and the output voltage acquired by the output detection device 71 is thereby reduced. Therefore, the amount of foreign matter adsorbed is estimated by comparing the potentials of the output terminals 61; 61a, 61b, 61c (divided pressure output) with the potential of the input terminal (power supply) 62 and the potential of the GND terminal 64. it can. It can be calculated in advance by experiments or the like how much output voltage (the potential of the output terminals 61; 61a, 61b, 61c = divided voltage output) with respect to the amount of adsorbed foreign matter. These pieces of information can be stored by the data storage means 72 described later.

  For this reason, a threshold value is provided in advance in the output voltage, and when the electrical output from the output terminals 61; 61a, 61b, 61c becomes equal to or less than the threshold value, the output detection device 71 determines that the rolling bearing is in an abnormal state. You should set it like this.

  In addition, the control unit 70 confirms the temporal change of the abnormal state based on the data storage unit 72 that stores the information determined by the output detection device 71 as the abnormal state and the past determination information stored in the data storage unit 72. Change confirmation means 73 is provided. For this reason, what amount of output voltage (output terminal 61; potential of 61a, 61b, 61c = divided voltage output) with respect to how much foreign matter is adsorbed, and before shifting to an abnormal state It is easy to grasp the remaining operation time and the like for each bearing unit 20.

    2A and 2B, when the magnetic materials 51c, 52c, and 53c are not disposed between the permanent magnets Ma and Mb, as a result of the experiment, the foreign matter is the surface of the permanent magnets Ma and Mb. There is a tendency to concentrate and adhere to. On the other hand, when the magnetic materials 51c, 52c, and 53c are arranged as in the wiring example shown in FIG. 3, the foreign matter adheres to the state over both the permanent magnets Ma and Mb and the magnetic materials 51c, 52c, and 53c. It turns out that it tends to be easy.

    From this result, it can be determined that the magnetic material 51c, 52c, 53c is more likely to cause a magnetic and electrical short circuit in the magnetic field between the permanent magnets Ma, Mb. Actually, a slight gap necessary to prevent an electrical short circuit is set between the permanent magnets Ma, Mb and the magnetic materials 51c, 52c, 53c due to factors other than the adhesion of foreign matter.

  In this embodiment, in particular, a plurality of sets of electrodes made of a pair of permanent magnets Ma and Mb are arranged, and the plurality of sets of electrodes are arranged with different gaps between the electrodes. Specifically, in each of the wiring examples shown in FIGS. 2A and 2B, the gap between the pair of permanent magnets Ma and Mb closer to the outer diameter than the gap between the pair of permanent magnets Ma and Mb closer to the inner diameter. Is set larger. In the wiring example of FIG. 3, the pair of permanent magnets Ma, Mb and the magnetic material 51c closer to the outer diameter than the gap between the pair of permanent magnets Ma, Mb near the inner diameter and the magnetic materials 51c, 52c, 53c. , 52c, 53c are set large. For this reason, it is possible to appropriately generate an electrical short circuit in the pair of permanent magnets Ma and Mb corresponding to foreign substances of various sizes.

  FIG. 5 is a graph showing a change in output voltage when the sensor output is one system, and FIG. 6 is a graph showing a change in output voltage when the sensor output is three systems.

  As shown in FIG. 5, when the sensor output is one system, the amount of foreign matter increases with the passage of time, and the output voltage decreases with the increase. When the output voltage is equal to or lower than the threshold value, the rolling bearing is determined to be in an abnormal state, and the control unit 70 issues an alarm.

Here, the voltage Vout at the output of the voltage dividing circuit is as follows when the input voltage is VDD.
Vout = [(R2-R4) / {R1 + (R2-R4)}] × VDD
However, the input voltage VDD is a difference between the potential of the input terminal (power supply) 62 and the potential of the GND terminal 64.

  As shown in FIG. 6, when the sensor output has three systems, the amount of foreign matter increases with the passage of time, and the output voltage decreases in each voltage dividing circuit according to the increase. When the output voltage of any of the voltage divider circuits is less than or equal to the threshold value, or when the output voltages of a plurality of voltage divider circuits are less than or equal to the threshold value, or the output voltages of all the voltage divider circuits are less than or equal to the threshold value When it becomes, it determines with a rolling bearing being in an abnormal state, and the control means 70 transmits a warning.

Here, the voltage Vout at the output of the voltage dividing circuit is as follows when the input voltage is VDD.
Vout1 = {(R4) / (R1 + R4)} × VDD
Vout2 = {(R5) / (R2 + R5)} × VDD
Vout3 = {(R6) / (R3 + R6)} × VDD
However, the input voltage VDD is a difference between the potential of the input terminal (power supply) 62 and the potential of the GND terminal 64.

Here, the gap between the pair of permanent magnets Ma, Mb near the outer diameter is set larger than the gap between the pair of permanent magnets Ma, Mb near the inner diameter, or the magnetic materials 51c, 52c, 53c. Is disposed, the pair of permanent magnets Ma, Mb and the magnetic material 51c, 52c closer to the outer diameter than the gap between the pair of permanent magnets Ma, Mb near the inner diameter and the magnetic material 51c, 52c, 53c. , 53c is set large,
1. Size of gap: (inner diameter side) gap 1 <(intermediate) gap 2 <(outer diameter side) gap 3
2. Resistance size: (inner diameter side) R4 <(intermediate) R5 <(outer diameter side) R6
3. Short circuit speed: (inner diameter side) output 1> (intermediate) output 2> (outer diameter side) output 3
Thus, a difference occurs in the timing of the change of the outputs 1 to 3.

  Due to the difference in the timing, the control means 70 can estimate how much the maximum diameter of the foreign matter contained in the lubricating oil is, and how much the foreign matter is mixed. For example, when the output 1 is less than or equal to the threshold, the diameter of the mixed foreign matter is rank 1, and when the output 2 is less than or equal to the threshold, the diameter of the mixed foreign matter is larger than rank 1. When rank 2 and output 3 are equal to or less than the threshold value, it is possible to determine that the diameter of the mixed foreign matter is rank 3 larger than rank 2 or the like.

  The data storage means 72 and the time-change confirmation means 73 can store the information of these determination data, and can utilize the information for the next determination and control of alarm transmission.

  In the above embodiment, the filter F is provided in the seal ring 40 that covers the opening of the bearing space of the rolling bearings 21 and 23. However, the place where the filter F is provided may be other than the seal ring 40. For example, a filter F that can capture foreign matter may be provided in the middle of the circulation paths 12 and 13, and the abnormality detection device having the above-described configurations may be attached to the filter F.

  The abnormality detection device for a rolling bearing according to the present invention can also be applied to devices other than oil pumps. In particular, the abnormality detection device for a rolling bearing according to the present invention needs to prevent foreign matter such as wear powder (iron powder, etc.) generated from the rolling bearing from entering an operating mechanism portion in the middle of a lubricating oil circulation path. It can be applied to a variety of devices.

1 Outer ring (outer raceway)
2 Inner ring (inner race)
DESCRIPTION OF SYMBOLS 3 Rolling body 4 Cage 5, 6, 7 Spacer 8 Holding member 10 Oil pump apparatus 11 Housing 12, 13 Circulation path 20 Bearing unit 21, 22, 23 Rolling bearing 30 Actuation mechanism part 31 Connection member 32 Shaft member 50 Substrate 51a , 51b Permanent magnet 60 Electric circuit 70 Control means 71 Output detector 72 Data storage means 73 Aging change confirmation means

Claims (7)

An inner ring and an outer ring,
A rolling element disposed in a bearing space between the inner ring and the outer ring;
A filter that allows passage of lubricating oil from within the bearing space and prevents passage of metal pieces;
A pair of permanent magnets disposed on the filter and spaced apart from each other;
An electrical circuit extending from both electrodes to the power source by using the pair of permanent magnets as electrodes,
An output detection device for detecting a state of the metal piece contained in the lubricating oil by detecting a change in the electrical output of the electric circuit accompanying the attachment of the metal piece between the pair of permanent magnets;
Bei to give a,
The filter includes a through hole for lubricating oil flow, and the pair of permanent magnets is an abnormality detection device for a rolling bearing disposed on both sides of the through hole . An inner ring and an outer ring,
A rolling element disposed in a bearing space between the inner ring and the outer ring;
A filter that allows passage of lubricating oil from within the bearing space and prevents passage of metal pieces;
A pair of permanent magnets disposed on the filter and spaced apart from each other;
An electrical circuit extending from both electrodes to the power source by using the pair of permanent magnets as electrodes,
An output detection device for detecting a state of the metal piece contained in the lubricating oil by detecting a change in the electrical output of the electric circuit accompanying the attachment of the metal piece between the pair of permanent magnets;
Bei to give a,
An abnormality detection device for a rolling bearing in which a magnetic material is disposed between the pair of permanent magnets via a gap . Said output detector electrical output is detected, the abnormality detecting device of a rolling bearing according to claim 1 or 2 is a divided output voltage in the electric circuit. The rolling bearing abnormality detection device according to any one of claims 1 to 3, wherein a plurality of sets of electrodes made of the pair of permanent magnets are arranged, and the plurality of sets of electrodes have different gaps between the electrodes. . Permanent magnets of said pair is provided with an electrically conductive coating layer on its surface, wherein the circuit board terminals constituting the coating layer and a part of the electrical circuit of claims 1, which is electrically connected to 4 An abnormality detection device for a rolling bearing according to any one of the above. The said output detection apparatus is an abnormality detection apparatus of the rolling bearing as described in any one of Claim 1 to 5 which determines an abnormal condition based on an electrical output and a predetermined threshold value. A data storage unit that stores information that the output detection device determines to be in an abnormal state, and a temporal change confirmation unit that checks a temporal change in the abnormal state based on past determination information stored in the data storage unit. The rolling bearing abnormality detection device according to any one of 1 to 6 .

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