Patent Publication Number: US-2018038413-A1

Title: Abnormality diagnosis system

Description:
TECHNICAL FIELD 
     The present invention relates to an abnormality diagnosis system. 
     RELATED ART 
     A machine facility such as a vehicle, a machine tool, a wind mill and the like is equipped with a variety of many bearings such as rolling bearings and the like. When wear or damage occurs at the machine facility as it is used for a long time, smooth rotation and sliding of the bearing are inhibited, so that an abnormal sound may be generated and the lifetime may be reduced. For this reason, in the related art, it is inspected whether an abnormality such as wear, damage and the like has occurred at the bearing, after the machine facility has been used for a predetermined time period. 
     The inspection is performed by disassembling a part of the machine facility, to which the bearing is incorporated, or the entire machine facility, and the damage or wear having occurred at the bearing is found by an inspection with operator&#39;s eyes. As a result of the inspection, when the abnormality such as wear, damage and the like is found at the bearing, the bearing is replaced with a new product so as to prevent a failure or trouble of the machine facility before happens. However, according to the inspection method of disassembling the part or whole of the machine facility and finding the damage or wear with operator&#39;s eyes, an operation of detaching the bearing from the machine facility and an operation of again incorporating the bearing, for which the inspection has been completed, to the machine facility require a great effort, which increases the maintenance cost of the machine facility. 
     In order to solve the above problem, an abnormality diagnosis device configured to perform abnormality diagnosis of the bearing at an actually operating state of the machine facility has been suggested. For example, a monitoring diagnosis system of a rotary machine equipment disclosed in Patent Document 1 is configured to compare a vibration level, which is detected by each vibration detection sensor, and a set alarm generation level for alarm determination at each provision position of the vibration detection sensors and for each operation pattern and displays an alarm with an alarm display means when the vibration level reaches the alarm generation level. Thereby, a place at which the abnormal vibration occurs is specified and the abnormal vibration place is clearly displayed. Also, an abnormality diagnosis device of a rolling bearing disclosed in Patent Document 2 is configured to perform abnormality diagnosis of the rolling bearing on the basis of an effective value of a vibration waveform measured using a vibration sensor and an effective value of an alternating-current component of an envelope waveform of the vibration waveform. Thereby, it is possible to implement the correct abnormality diagnosis. 
     CITATION LIST 
     Patent Document 
     Patent Document 1: Japanese Patent Application Publication No. 2009-109350A 
     Patent Document 2: Japanese Patent Application Publication No. 2011-154020A 
     SUMMARY OF THE INVENTION 
     Problems To Be Solved 
     In the meantime, a variety of devices such as a motor incorporated into the machine facility are also inspected by disassembling parts of the machine facility, to which the devices are incorporated, or the entire machine facility. Therefore, it is preferably to perform the abnormality diagnosis of the diverse devices upon the abnormality diagnosis of the bearing, from standpoints of the maintenance cost of the machine facility, and the like. However, according to the inventions disclosed in Patent Documents 1 and 2, the abnormality diagnosis is simply performed for the members at which the sensors are provided and cannot be performed for a device except for the members to which the sensors are provided. 
     The present invention has been made in view of the above situations, and an object thereof is to provide an abnormality diagnosis system capable of performing abnormality diagnosis of a bearing and abnormality diagnosis of a device disposed around the bearing. 
     Means for Solving Problems 
     The above object of the present invention is achieved by following configurations.
         (1) An abnormality diagnosis system including:   a bearing that has a plurality of components;   one sensor that is provided at the component and that is configured to detect surrounding signals; and   an abnormality diagnosis device that is configured to diagnose abnormality of the bearing and abnormality of a device disposed around the bearing, based on signals output from the sensor.   (2) The abnormality diagnosis system of the above (1), wherein the abnormality diagnosis device determines that the bearing or the device is abnormal, when an output value of the sensor increases or exceeds a predetermined threshold value.   (3) The abnormality diagnosis system of the above (1) or (2), wherein the sensor is provided in the vicinity of an axial end portion of a bearing ring of the bearing.   (4) The abnormality diagnosis system of the above (1) or (2), wherein the sensor is provided in the vicinity of a raceway surface of a bearing ring of the bearing.   (5) The abnormality diagnosis system of any one of the above (1) to (4), wherein the sensor is a temperature sensor.   (6) The abnormality diagnosis system of any one of the above (1) to (4), wherein the sensor is a vibration sensor.   (7) The abnormality diagnosis system of any one of the above (1) to (4), wherein the sensor is a load sensor.   (8) The abnormality diagnosis system of any one of the above (1) to (7), wherein the sensor is provided at a fixed ring of the bearing.   (9) The abnormality diagnosis system of any one of the above (1) to (7), wherein the sensor is provided at a rotary ring of the bearing.       

     Effects of the Invention 
     According to the present invention, it is possible to perform the abnormality diagnosis of the bearing and the abnormality diagnosis of the device disposed around the bearing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view of an abnormality diagnosis system in accordance with a first illustrative embodiment. 
         FIG. 2  is a graph depicting a relation between a detected temperature of the sensor and time. 
         FIG. 3  is a graph depicting a relation between a detected temperature of the sensor and time when an abnormality has occurred in any one of a rolling bearing, a motor and a pump. 
         FIG. 4  is a schematic view of an abnormality diagnosis system in accordance with a modified embodiment of the first illustrative embodiment. 
         FIG. 5  is a schematic view of an abnormality diagnosis system in accordance with a modified embodiment of the first illustrative embodiment. 
         FIG. 6  is a schematic view of an abnormality diagnosis system in accordance with a modified embodiment of the first illustrative embodiment. 
         FIG. 7  is a schematic view of an abnormality diagnosis system in accordance with a second illustrative embodiment. 
         FIG. 8  is a schematic view of an abnormality diagnosis system in accordance with a modified embodiment of the second illustrative embodiment. 
         FIG. 9  is a schematic view of an abnormality diagnosis system in accordance with a modified embodiment of the second illustrative embodiment. 
         FIG. 10  is a schematic view of an abnormality diagnosis system in accordance with a modified embodiment of the second illustrative embodiment. 
         FIG. 11  is a sectional view of an angular ball bearing in which a sensor is disposed. 
         FIG. 12A  is a sectional view of a cylindrical roller bearing in which a sensor is disposed. 
         FIG. 12B  is a sectional view of a cylindrical roller bearing in which a sensor is disposed. 
         FIG. 13  is a sectional view of a conical roller bearing in which a sensor is disposed. 
         FIG. 14  is a sectional view of a self-aligning roller bearing in which a sensor is disposed. 
     
    
    
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     Hereinafter, an abnormality diagnosis system in accordance with illustrative embodiments of the present invention will be described with reference to the drawings. 
     First Illustrative Embodiment 
     As shown in  FIG. 1 , an abnormality diagnosis system  1  of a first illustrative embodiment includes a rolling bearing (deep groove ball bearing)  10 , only one sensor  21  provided in the rolling bearing  10 , and an abnormality diagnosis device  30  configured to diagnose abnormalities of the rolling bearing  10  and a variety of devices (for example, a motor  41  and a pump  42 ) on the basis of signals output from the sensor  21 . 
     The rolling bearing  10  includes an outer ring  11  (a bearing ring that is a fixed ring) having an outer ring raceway surface  11  a formed on an inner peripheral surface thereof, an inner ring  13  (a bearing ring that is a rotary ring) having an inner ring raceway surface  13   a  formed on an outer peripheral surface thereof, a plurality of balls  15  disposed to be rollable between the outer ring raceway surface  11   a  and the inner ring raceway surface  13   a,  a retainer  17  configured to hold the plurality of balls  15  to be rollable and a pair of seal members  19  fixed at both axial sides of the inner peripheral surface of the outer ring  11 . That is, the rolling bearing  10  includes a plurality of components such as the outer ring  11 , the inner ring  13 , the ball  15 , the retainer  17 , the seal member  19  and the like. 
     The inner ring  13  is a rotary ring externally fitted and fixed to a shaft  3  and configured to rotate together with the shaft  3 . At one axial end-side (a left side in  FIG. 1 ) of the rolling bearing  10 , a motor  41  (a device) is fixed to the shaft  3  and the shaft  3  is configured to be rotatively driven by a rotor (not shown) of the motor  41 . Also, at the other axial end-side (a right side in  FIG. 1 ) of the rolling bearing  10 , a pump  42  is fixed to the shaft  3 , and a driving force of the motor  41  is transmitted to the pump  42  via the shaft  3 . 
     The outer ring  11  is a fixed ring internally fitted and fixed to a housing (not shown) and configured not to rotate. The inner peripheral surface of the outer ring  11  is formed at both axial sides of the outer ring raceway surface  11   a  with a pair of seal grooves  11   b  for fixing the pair of seal members  19  thereto. Each of the pair of seal members  19  is a non-contact type extending radially and configured to face the outer peripheral surface of the inner ring  13  via a gap. Thereby, the pair of seal members  19  is configured to seal a space between the outer ring  11  and the inner ring  13  and to prevent foreign matters from being introduced into the bearing from an outside. 
     In the outer ring  11 , the sensor  21  configured to detect surrounding signals is embedded. In the first illustrative embodiment, the sensor  21  is a temperature sensor  21  provided at an axially central portion in the vicinity of the outer peripheral surface of the outer ring  11 . A temperature that is to be detected by the temperature sensor  21  is influenced by heats generated from the rolling bearing  10 , the motor  41  and the pump  42 . 
     The temperature sensor  21  is configured to output and transmit the detected temperature to the abnormality diagnosis device  30 . The abnormality diagnosis device  30  is a microcomputer, for example. A program recorded in the microcomputer is executed, so that respective units such as a data collection unit  31  execute following processing. 
     A data collection unit  31  of the abnormality diagnosis device  30  is configured to collect the output data from the temperature sensor  21 . A data processing unit  33  of the abnormality diagnosis device  30  is configured to process the collected output data and to store the respective output data. A state determination unit  35  of the abnormality diagnosis device  30  determines that at least one of the rolling bearing  10 , the motor  41  and the pump  42  is abnormal, when an output value of the temperature sensor  21  first increases from a rated temperature or first exceeds a predetermined threshold value. 
     In a machine facility in which the abnormality diagnosis system  1  is incorporated, the bearing  10 , the motor  41  and the pump  42  generate the heat. For this reason, as shown in  FIG. 2 , in a temperature rising curve obtained from the output values of the temperature sensor  21 , the temperature increases for the time being after operations of the rolling bearing  10 , the motor  41  and the pump  42  start. However, at a point of time at which the temperature reaches a predetermined temperature (rated temperature Ta) after predetermined time elapses, the heats generated from the rolling bearing  10 , the motor  41  and the pump  42  and the heat to be escaped to the surrounding are balanced, so that a steady state is formed. 
     Herein, as shown in  FIG. 3 , at time t, when the motor  41  abnormally generates heat due to any cause, when the rolling bearing  10  abnormally generates heat due to causes such as seizing, wear and the like and when the pump  42  abnormally generates heat due to any cause, the output value of the temperature sensor  21  increases and exceeds a predetermined threshold value Tb. 
     Therefore, the abnormality diagnosis device  30  determines that at least one of the rolling bearing  10 , the motor  41  and the pump  42  is abnormal, when the output value of the temperature sensor  21  increases or exceeds the predetermined threshold value Tb. 
     Like this, according to the abnormality diagnosis system  1  of the first illustrative embodiment, it is possible to effectively perform the abnormality diagnosis of the rolling bearing  10  and the abnormality diagnosis of the devices (the motor  41  and the pump  42 ) disposed around the rolling bearing  10 . In particular, since it is sufficient to provide the rolling bearing  10  with only one sensor, it is possible to save the cost of the product and to improve the handling property by simplifying wiring for sensor output and wiring for power feeding. 
     In the meantime, the present invention is not limited to the above illustrative embodiment and can be appropriately changed and modified. 
     The provision position of the sensor  21  can be appropriately changed so that it is to be a position or a phase suitable for a target of which an abnormality is to be detected. For example, as shown in  FIG. 4 , the sensor  21  may be disposed in the vicinity of one axial end portion of the outer ring  11  so as to improve sensitivity to an abnormality of the motor  41 . That is, the sensor may be arranged at a position that is suitable for abnormality detection of the motor  41 . Also, as shown in  FIG. 5 , the sensor  21  may be disposed in the vicinity of the other axial end portion of the outer ring  11  so as to improve sensitivity to an abnormality of the pump  42 . That is, the sensor may be arranged at a position that is suitable for abnormality detection of the pump  42 . Also, as shown in  FIG. 6 , the sensor  21  may be disposed in the vicinity of the outer ring raceway surface  11   a  of the outer ring  11  so as to improve sensitivity to an abnormality of the rolling bearing  10 . That is, the sensor may be arranged at a position that is suitable for abnormality detection of the rolling bearing  10 . 
     Meanwhile, in the specification, the description “the vicinity of a surface” and “the vicinity of an end portion” indicate a position matched with the surface or a surface of the end portion, or a position slightly recessed into a member from the surface or a surface of the end portion. 
     Second Illustrative Embodiment 
     In the below, an abnormality diagnosis system  2  including a rolling bearing (deep groove ball bearing)  10  in which the sensor  21  is disposed in the inner ring  13  is described. The rolling bearing  10  of the second illustrative embodiment has the similar configuration to the first illustrative embodiment, except that the sensor  21  is disposed in the inner ring  1 , contrary to the first illustrative embodiment where the sensor  21  is disposed in the outer ring  11 . Thus, the common members are denoted with the same reference numerals and the descriptions thereof are simplified or omitted. 
     As shown in  FIG. 7 , the abnormality diagnosis system  2  of the second illustrative embodiment includes the rolling bearing  10 , only one sensor  21  provided in the inner ring  13  (a bearing ring that is a rotary ring) of the rolling bearing  10 , and the abnormality diagnosis device  30  configured to diagnose abnormalities of the rolling bearing  10  and a variety of devices (for example, the motor  41  and the pump  42 ) on the basis of signals output from the sensor  21 . 
     In the inner ring  13 , the sensor  21  configured to detect surrounding signals is embedded. In the second illustrative embodiment, the sensor  21  is a temperature sensor  21  provided at an axially central portion in the vicinity of the inner peripheral surface of the inner ring  13 . A temperature that is to be detected by the temperature sensor  21  is influenced by heats generated from the rolling bearing  10 , the motor  41  and the pump  42 . 
     The temperature sensor  21  is configured to output and transmit the detected temperature to the abnormality diagnosis device  30 . The abnormality diagnosis device  30  is a microcomputer, for example. A program recorded in the microcomputer is executed, so that respective units such as a data collection unit  31  execute respective processing similar to the first illustrative embodiment. 
     Like this, according to the abnormality diagnosis system  2  of the second illustrative embodiment, it is possible to effectively perform the abnormality diagnosis of the rolling bearing  10  and the abnormality diagnosis of the devices (the motor  41  and the pump  42 ) disposed around the rolling bearing  10 . In particular, since it is sufficient to provide the rolling bearing  10  with only one sensor, it is possible to save the cost of the product and to improve the handling property by simplifying wiring for sensor output and wiring for power feeding. 
     In the meantime, the configuration of the second illustrative embodiment can be appropriately changed and modified, like the first illustrative embodiment. 
     The provision position of the sensor  21  can be appropriately changed so that it is to be a position or a phase suitable for a target of which an abnormality is to be detected. For example, as shown in  FIG. 8 , the sensor  21  may be disposed in the vicinity of one axial end portion of the inner ring  13  so as to improve sensitivity to an abnormality of the motor  41 . That is, the sensor may be arranged at a position that is suitable for abnormality detection of the motor  41 . Also, as shown in  FIG. 9 , the sensor  21  may be disposed in the vicinity of the other axial end portion of the inner ring  13  so as to improve sensitivity to an abnormality of the pump  42 . That is, the sensor may be arranged at a position that is suitable for abnormality detection of the pump  42 . Also, as shown in  FIG. 10 , the sensor  21  may be disposed in the vicinity of the inner ring raceway surface  13   a  of the inner ring  13  so as to improve sensitivity to an abnormality of the rolling bearing  10 . That is, the sensor may be arranged at a position that is suitable for abnormality detection of the rolling bearing  10 . 
     Also, the provision part of the sensor  21  is not limited to the outer ring  11  or the inner ring  13  inasmuch as it is a component of the rolling bearing  10 . For example, the sensor may be provided in the retainer  17  or the seal member  19 . 
     Also, the sensor  21  to be provided is not particularly limited inasmuch as it can monitor the state of the rolling bearing  10  or the device (for example, the motor  41  or the pump  42 ) disposed around the rolling bearing  10 . For example, a vibration sensor or a load sensor may be adopted. Herein, like the second illustrative embodiment, when the sensor is provided in the inner ring  13 , which is a rotary ring, heat, vibration, load and the like are likely to be transmitted from the shaft  3 . Therefore, it is possible to rapidly detect the behavior, as compared to the configuration where the sensor is provided at the other component of the rolling bearing  10 . 
     When the load sensor is adopted as the sensor to be provided, if the load sensor is provided in the outer ring  11 , which is a fixed ring, the load sensor should be provided in a load zone, which limits a provision phase on a circumference. However, when providing the load sensor in the inner ring  13 , which is a rotary ring, like the second illustrative embodiment, if the load sensor is provided at any phase on the circumference, it is possible to detect the respective behaviors. 
     Also, the signal transmission method from the sensor to the data collection unit  31  of the abnormality diagnosis device  30  may be any method, irrespective of whether it is a wired or wireless method. 
     When the abnormality diagnosis device  30  determines the abnormality of the rolling bearing  10 , the motor  41  or the pump  42 , the abnormality diagnosis device may notify the abnormality to an upper system so as to automatically stop the machine facility or issue a warning to an operator and a manager with an alarm, a screen display and the like. 
     The devices to be disposed around the rolling bearing  10  are not limited to the motor  41  and the pump  42 , and any device can be adopted. 
     In the meantime, the rolling bearing  10  is a radial rolling bearing. However, the present invention is not limited thereto and can be applied to the other types of rolling bearings. An example where the present invention is applied to the other types of rolling bearings is described. 
       FIG. 11  is a sectional view of an angular ball bearing  10 A in which the sensor  21  is disposed. In the shown example, the angular ball bearing  10 A includes the outer ring  11 , the inner ring  13 , the plurality of balls  15  and the retainer  17  configured to hold the plurality of balls  15  to be rollable. The sensor  21  is disposed at an axially central portion P 1  in the vicinity of the outer peripheral surface of the outer ring  11 . 
     Also, the present invention is not limited to the above configuration. That is, also in the angular ball bearing  10 A, as described above, the sensor  21  may be disposed at a position P 2  in the vicinity of one axial end portion in the vicinity of the outer peripheral surface of the outer ring  11 , a position P 3  in the vicinity of the other axial end portion in the vicinity of the outer peripheral surface of the outer ring  11  or a position P 4  in the vicinity of the outer ring raceway surface  11   a  of the outer ring  11 . Also, the sensor  21  may be disposed at an axially central portion P 5  in the vicinity of the inner peripheral surface of the inner ring  13 , a position P 6  in the vicinity of one axial end portion in the vicinity of the inner peripheral surface of the inner ring  13 , a position P 7  in the vicinity of the other axial end portion in the vicinity of the inner peripheral surface of the inner ring  13  or a position P 8  in the vicinity of the inner ring raceway surface  13   a  of the inner ring  13 . 
       FIG. 12A  is a sectional view of a cylindrical roller bearing  10 B in which the sensor  21  is disposed, and  FIG. 12B  is a sectional view of a cylindrical roller bearing  10 C in which the sensor  21  is disposed. The cylindrical roller bearings  10 B,  10 C include, respectively, the outer ring  11 , the inner ring  13 , a plurality of rollers  51  and the retainer  17  configured to hold the plurality of rollers  51  to be rollable. The cylindrical roller bearing  10 B shown in  FIG. 12A  has collar portions  53 ,  53  provided at both axial end portions of the inner peripheral surface of the outer ring  11  and protruding radially inwards. The cylindrical roller bearing  10 C shown in  FIG. 12B  has collar portions  54 ,  54  provided at both axial end portions of the outer peripheral surface of the inner ring and protruding radially outwards. In any of the bearings  10 B,  10 C, the sensor  21  is disposed at the axially central portion P 1  in the vicinity of the outer peripheral surface of the outer ring  11 . Also in this configuration, the sensor  21  may be disposed at any position of P 1  to P 8 . 
       FIG. 13  is a sectional view of a conical roller bearing  10 D in which the sensor  21  is disposed. The conical roller bearing  10 D includes the outer ring  11 , the inner ring  13 , a plurality of conical rollers  55  and the retainer  17  configured to hold the plurality of conical rollers  55  to be rollable. The sensor  21  is disposed at the axially central portion P 1  in the vicinity of the outer peripheral surface of the outer ring  11 . Also in this configuration, the sensor  21  may be disposed at any position of P 1  to P 8 . 
       FIG. 14  is a sectional view of a self-aligning roller bearing  10 E in which the sensor  21  is disposed. The self-aligning roller bearing  10 E includes the outer ring  11 , the inner ring  13 , a plurality of rollers  57  disposed in two rows and the retainer  17  configured to hold the plurality of rollers  57  to be rollable. The sensor  21  is disposed at the axially central portion P 1  in the vicinity of the outer peripheral surface of the outer ring  11 . Also in this configuration, the sensor  21  may be disposed at any position of P 1  to P 8 . 
     Each of the bearings shown in  FIGS. 11 to 14  may include a seal member, as a component, in addition to the outer ring  11 , the inner ring  13 , the rolling element (the ball  15 , the cylindrical roller  51 , the conical roller  55 , the roller  57 ) and the retainer  17 , and the sensor  21  may be disposed at any one of the components. Also, the rotary ring may be the outer ring  11  or the inner ring  13 . In any configuration, it is possible to achieve the operational effects similar to the first and second illustrative embodiments. 
     The subject application is based on a Japanese Patent Application No. 2015-92672 filed on Apr. 30, 2015 and a Japanese Patent Application No. 2015-92673 filed on Apr. 30, 2015, the contents of which are incorporated herein by reference. 
     DESCRIPTION OF REFERENCE NUMERALS 
     
         
           1 ,  2 : abnormality diagnosis system 
           10 : bearing 
           11 : outer ring (component, bearing ring) 
           13 : inner ring (component, bearing ring) 
           15 : ball (component) 
           17 : retainer (component) 
           19 : seal member (component) 
           21 : temperature sensor 
           30 : abnormality diagnosis device 
           31 : data collection unit 
           33 : data processing unit 
           35 : state determination unit 
           41 : motor (device) 
           42 : pump (device) 
           51 : cylindrical roller (component) 
           55 : conical roller (component) 
           57 : roller (component)