Determination device

Abstract

The probe is provided with: a probe main body that comes into contact with a surface to be measured of a bearing and detects the impedance of the bearing; and a substantially cylindrical housing having a hole for accommodating the probe body therein, the switch being attachable / detachable to / from the housing.

Description

Technical Field

[0001] This invention relates to a determination device. Background Technology

[0002] For example, rolling bearings used in papermaking machinery, wind power generation equipment, mining / construction equipment, and railway vehicles operate under harsh lubrication conditions with heavy loads and the intrusion of foreign objects and water, making bearing raceway delamination a problem. Delamination in rolling bearings not only has the potential to cause significant damage to products and equipment but also impacts manufacturing delivery dates and schedules. To prevent sudden delamination, rolling bearings are periodically disassembled, cleaned, and their raceway surfaces visually inspected. However, predicting the remaining life of bearings based on visual inspections (an estimate of the period until delamination occurs) relies on the operator's experience and skill, making quantitative prediction difficult.

[0003] In response, Patent Document 1 discloses an eddy current testing device that uses electromagnetic induction to detect defects generated in conductive materials such as metals. In the eddy current testing device of Patent Document 1, scanning is performed while maintaining a probe at a certain angle and distance relative to the object under test. The angle and distance between the probe and the object under test are determined by Patent Document 1. Figures 2-4 The probe operating unit described herein is maintained. This probe operating unit consists of various components such as a grip, shaft, collar, bolt, rotary locking nut, roller, momentary switch, and encoder.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2005-201778 Summary of the Invention

[0007] The technical problem that the invention aims to solve

[0008] As described above, in Patent Document 1, the probe operation part, including a momentary switch, is integrated with the probe, resulting in a large probe size. Therefore, in situations where the probe is inserted into the gap of the object being measured, it may not be feasible to use a large probe like the one in Patent Document 1, which integrates the switch and other components. On the other hand, it is also considered that installing a switch on the probe would make it easier to measure while operating the switch with the hand holding the probe.

[0009] The present invention was made in view of the above-mentioned technical problems, and its object is to provide a judgment device that can remove and install the switch from the probe according to the situation and has excellent operability.

[0010] Technical solutions for solving technical problems

[0011] Therefore, the above-mentioned objective of the present invention is achieved by the structure described below [1].

[0012] [1] A determination device comprising: a probe that induces eddy currents in a bearing by applying an alternating magnetic field, thereby detecting the impedance of the bearing;

[0013] A switch that sends a measurement control signal to switch the start and end of the acquisition of the measurement signal of the impedance detected by the probe;

[0014] The fatigue assessment unit determines the fatigue degree or remaining life of the bearing based on its resistance.

[0015] The fatigue determination unit includes:

[0016] The determination graph storage unit stores a determination graph containing the relationship between the impedance characteristics of the bearing and the fatigue degree or remaining life of the bearing.

[0017] The measurement switching unit switches between a measurement implementation state and a measurement non-implementation state based on the state of the measurement control signal.

[0018] The data holding unit holds the measurement signal during the measurement execution state;

[0019] The impedance characteristic calculation unit calculates the impedance characteristics of the bearing based on the maintained measurement signal;

[0020] The determination unit, based on the bearing's impedance characteristics and the determination diagram, determines the bearing's fatigue level or remaining life.

[0021] The probe comprises: a probe body that abuts against the measuring surface of the bearing to detect the impedance of the bearing; a housing that is generally cylindrical and has an internal hole for accommodating the probe body, and the switch being detachable from the housing.

[0022] Invention Effects

[0023] The determination device according to the present invention allows for the removal and installation of the switch from the probe depending on the situation, providing excellent operability. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of a device for determining the fatigue level or remaining life of a bearing.

[0025] Figure 2 This is a schematic diagram of the fatigue assessment unit.

[0026] Figure 3 This is a schematic diagram showing the state of the impedance of the track surface 61 of the outer ring 60 of the rolling bearing measured by probe 10.

[0027] Figure 4 This is a 3D view of the probe.

[0028] Figure 5 This is a cross-sectional view of the probe.

[0029] Figure 6 It is a cross-sectional view showing the state in which the probe is in perpendicular contact with the outer track surface.

[0030] Figure 7 Is Figure 6 The diagram viewed along the direction marked VII.

[0031] Figure 8 yes Figure 6 Sectional views from VIII 1 to VIII 1 or from VIII 2 to VIII 2.

[0032] Figure 9 yes Figure 7 An enlarged view of the probe in the image.

[0033] Figure 10 It is a cross-sectional view showing the state in which the probe is in perpendicular contact with the inner track surface.

[0034] Figure 11 Is Figure 10 The image is viewed along the direction marked XI.

[0035] Figure 12 yes Figure 11 XII-XII sectional view.

[0036] Figure 13 yes Figure 11 XIII-XIII view section.

[0037] Figure 14 yes Figure 11 An enlarged view of the probe in the image.

[0038] Figure 15 yes Figure 10 A magnified view of a portion of the image.

[0039] Figure 16 This diagram shows the state when a switch is installed on the probe.

[0040] Figure 17 This indicates that the switch is turned from... Figure 16 The diagram shows the state of the probe moving towards the front end.

[0041] Figure 18 This is a three-dimensional view of the switch as seen from the front side.

[0042] Figure 19 This is a three-dimensional view of the switch as seen from the back side. Detailed Implementation

[0043] The following describes in detail, based on the accompanying drawings, the apparatus for determining the fatigue degree or remaining life of a bearing according to various embodiments of the present invention.

[0044] Figure 1 This is a schematic diagram of a device for determining the fatigue level or remaining life of a bearing. (Example) Figure 1 As shown, the determination device 1 includes: a probe 10, which induces eddy currents in the bearing by applying an alternating magnetic field and detects the bearing impedance; a switch 30, which sends a measurement control signal S2 to switch the start and end of the acquisition of the measurement signal S1 of the impedance detected by the probe 10; an input unit 40, which acquires the measurement signal S1 and the measurement control signal S2; and a fatigue determination unit 50, which determines the fatigue degree or remaining life of the bearing based on the bearing impedance.

[0045] A coil (not shown) is built into the probe 10. By applying an excitation current through the coil within the probe 10, an alternating magnetic field is applied to the bearing (e.g., the outer ring, inner ring, or rolling element of a rolling bearing) to be measured, thereby inducing eddy currents. The impedance generated in the coil due to these eddy currents is detected, thus allowing for the non-destructive determination of the metal structure (e.g., the amount of retained austenite). Examples of bearing surfaces to be measured include the raceway surface, outer peripheral surface, and axial end faces of the outer ring; the raceway surface, inner peripheral surface, and axial end faces of the inner ring; the circumferential surface of the rolling element; and the circumferential surface of the cage.

[0046] When the probe 10 is in contact with the bearing's measurement surface, the bearing's impedance measurement signal S1 is always sent to the fatigue determination unit 50 via the input unit 40. However, as will be described later, the fatigue determination unit 50 does not always acquire the measurement signal S1, but switches between acquiring and not acquiring the measurement signal S1 based on the state of the measurement control signal S2 sent by the switch 30.

[0047] Switch 30 is a component that can be pressed by a user. For example, when switch 30 is pressed (ON state), a measurement control signal S2 is sent to input unit 40 to switch the start and end of the acquisition of measurement signal S1; when switch 30 is not pressed (OFF state), the measurement control signal S2 is not sent to input unit 40. Furthermore, for example, when measurement control signal S2 is sent to input unit 40, measurement signal S1 is acquired by fatigue determination unit 50, and the measurement is performed; when measurement control signal S2 is not sent to input unit 40, measurement signal S1 is not acquired by fatigue determination unit 50, and the measurement is not performed.

[0048] Input unit 40 includes: an A / D converter (not shown), which is connected via cable 25 (see below) Figure 3The input unit 40 is connected to the probe 10 to acquire the measurement signal S1 of the bearing impedance detected by the probe 10; the digital input / output unit (not shown) is connected to the switch 30 to acquire the measurement control signal S2 sent by the switch 30. The measurement signal S1 and the measurement control signal S2 are sent to the fatigue determination unit 50 via the input unit 40.

[0049] Figure 2 This is a schematic diagram of the fatigue assessment unit. (For example...) Figure 2 As shown, the fatigue determination unit 50 includes: a determination chart storage unit 51, which stores a determination chart containing the relationship between the bearing's impedance characteristics (resistive components and reactive components) and the bearing's fatigue degree or remaining life; a measurement switching unit 53, which switches between a measurement implementation state and a measurement non-implementation state based on the state of the measurement control signal S2; a data holding unit 55, which holds the measurement signal S1 in the measurement implementation state; an impedance characteristic calculation unit 57, which calculates the bearing's impedance characteristics (resistive components and reactive components) based on the held measurement signal S1; a determination unit 59, which determines the bearing's fatigue degree or remaining life based on the bearing's impedance characteristics (resistive components and reactive components) and the determination chart; and a display unit 58, which displays the determination result.

[0050] The fatigue assessment unit 50 may include, for example, a computer with peripheral components such as a processor and storage devices. The processor may be, for example, a CPU (Central Processing Unit) or an MPU (Micro-Processing Unit). The storage device may be any one of a semiconductor storage device, a magnetic storage device, or an optical storage device. The storage device may include registers, cache memory, ROM (Read Only Memory) used as main storage, and RAM (Random Access Memory), etc. The fatigue assessment unit 50 may also be constructed using dedicated hardware for performing various information processing tasks. For example, the fatigue assessment unit 50 may also include functional logic circuits set in general-purpose semiconductor integrated circuits. For example, the fatigue assessment unit 50 may also include programmable logic devices (PLDs) such as field-programmable gate arrays (FPGAs).

[0051] The fatigue assessment unit 50 calculates the remaining life of the bearing by referring to the correlation between the impedance characteristics measured by the probe 10 and the assessment diagram stored in the assessment diagram storage unit 51, and displays the result on a display unit 58 such as a display screen.

[0052] Figure 3This is a schematic diagram showing the state of the impedance measured by probe 10 on the track surface 61 of the outer ring 60 of the rolling bearing. (Example) Figure 3 As shown, the probe 10 contacts the track surface 61, and eddy currents are induced in the track surface 61 by applying an alternating magnetic field, thereby detecting the impedance of the track surface 61. The measured impedance measurement signal S1 is transmitted to the input unit 40 via the cable 25. Thus, when the track surface 61 of the outer ring 60 is the object of measurement, the determination map storage unit 51 of the fatigue determination unit 50 stores in advance a determination map that includes the relationship between the resistive and reactive components of the impedance characteristics of the track surface 61 as the outer ring 60 and the fatigue degree or remaining life of the outer ring 60. Therefore, if the impedance characteristics of the track surface 61 of the outer ring 60 are measured, the fatigue degree or remaining life of the outer ring 60 is determined based on the determination map.

[0053] The measurement switching unit 53 switches between a measurement implementation state (where the measurement signal S1 is input into the fatigue determination unit 50 and measurement is performed) and a measurement non-implementation state (where the measurement signal S1 is not input into the fatigue determination unit 50 and measurement is not performed) based on the state switching of the measurement control signal S2. For example, the measurement switching unit 53 is set to the measurement implementation state when the measurement control signal S2 is sent from the switch 30 to the input unit 40, and to the measurement non-implementation state when the measurement control signal S2 is not sent from the switch 30 to the input unit 40. Therefore, after confirming that the probe 10 is in correct contact with the track surface 61 of the outer ring 60, the user presses the switch 30, thereby switching the determination device 1 to the measurement implementation state.

[0054] The data holding unit 55 holds the measurement signal S1 of the impedance of the track surface 61 of the outer ring 60 during the measurement implementation state.

[0055] The impedance characteristic calculation unit 57 calculates the resistive and reactive components of the impedance of the track surface 61 of the outer ring 60 based on the measurement signal S1 held in the data holding unit 55.

[0056] The determination unit 59 determines the fatigue level or remaining life of the outer ring 60 based on the resistive and reactive components of the impedance of the track surface 61 of the outer ring 60 calculated by the impedance characteristic calculation unit 57, and the determination chart stored in the determination chart storage unit 51. The determined fatigue level or remaining life of the outer ring 60 is displayed on the display unit 58.

[0057] The fatigue degree or remaining life of a bearing is determined by a determination device 1 having the structure described above. However, in order to accurately measure the bearing impedance, it is necessary to ensure that the probe 10 is stably in contact with the surface to be measured in the correct orientation. The correct orientation of the probe 10 refers, for example, to the orientation in which the probe 10 is perpendicular to the surface to be measured. The structure of the probe 10 used to ensure that the probe 10 is stably in contact with the bearing in the correct orientation during measurement will be described in detail.

[0058] Figure 4This is a 3D view of the probe. Figure 5 This is a cross-sectional view of the probe. (For example...) Figure 4 and Figure 5 As shown, the probe 10 includes: a generally cylindrical probe body 11 that abuts against the measuring surface of the bearing to detect the impedance of the bearing; a housing 13 having an axially extending sliding hole 14 inside, the housing 13 being accommodated in the sliding hole 14 in a manner that allows it to slide axially; a contact portion 15 located at the front end of the housing 13 and capable of abutting against the measuring surface of the bearing; and a helical spring 17 located in the sliding hole 14 of the housing 13 as a force-applying spring that applies axial force to the probe body 11 relative to the housing 13.

[0059] The housing 13 is along the axial direction (the length direction of the housing 13). Figure 5 The housing 13 is an elongated, generally cylindrical structure extending vertically, formed by axially connecting a generally cylindrical base 13a and a generally cuboid front end 13b coaxially arranged. The outer peripheral surface 13f of the base 13a is cylindrical, and the front end 13b has four planar outer peripheral surfaces 13d. The housing 13 is made of resin to suppress its influence on impedance measurement. A sliding hole 14 extends axially through the base 13a and the front end 13b of the housing 13.

[0060] The sliding hole 14 has the same diameter throughout its axial direction, therefore the inner diameter of the base 13a and the inner diameter of the front end 13b are the same. On the other hand, the outer diameter of the front end 13b is larger than the outer diameter of the base 13a, therefore, a step portion 13c perpendicular to the axial direction is formed at the connection between the front end 13b and the base 13a. The user, for example, holds the base 13a of the housing 13 so that the probe 10 touches the surface to be measured. The user may also hold the front end 13b of the housing 13.

[0061] The sliding hole 14 is formed at the front end of the housing 13. Figure 5 The front end opening 14a of the lower part and the base formed in the housing 13 Figure 5 The probe body 11 has a base opening 14b at its upper part. As described later, the probe body 11 is subjected to force by a helical spring 17 toward the front end of the probe 10, and by this force, the probe body 11 can protrude outward from the front end opening 14a of the sliding hole 14. A cover 16 with a through hole 16a at its center is embedded in the base opening 14b of the sliding hole 14. A cable 25 connected to the probe body 11 is led outward from the through hole 16a of the cover 16.

[0062] An elongated hole 13e is formed radially through one of the four outer peripheral surfaces 13d on the front end portion 13b of the housing 13. The elongated hole 13e is an elongated hole whose axial dimension is longer than its dimensions in the two directions perpendicular to the axial direction. A pair of pins 24, 24, fixed to the support portion 22 of the probe body 11 (described later), are disposed in the elongated hole 13e. When the probe body 11 slides axially, the pair of pins 24, 24 slide within the elongated hole 13e. Furthermore, the pair of pins 24, 24, and the axial ends of the elongated hole 13e (…) Figure 5 The upper and lower ends of the probe body 11 are in contact to restrict sliding, thereby limiting the axial movement distance of the probe body 11.

[0063] The probe body 11 is divided into a probe portion 21 and a support portion 22 that houses the probe portion 21 and is slidable relative to the sliding hole 14 of the housing 13. By making the probe portion 21 and the support portion 22 separate, in the event of damage to either one, the parts can be replaced independently, thus reducing costs. The probe portion 21 and the support portion 22 are made of resin to suppress any influence on impedance measurement.

[0064] The probe portion 21 is roughly cylindrical in shape, and a coil (not shown) is embedded inside. At the base end side of the probe portion 21 ( Figure 5 A cable 25 for extracting the measurement signal S1 is connected to the upper side of the base 14. The cable 25 extends within the sliding hole 14 and is led outward from the through hole 16a of the cover 16 provided in the base opening 14b. The led-out cable 25 connects to the input section 40 (see reference 14b). Figure 1 )connect.

[0065] The support portion 22 is a generally cylindrical shape that covers the probe portion 21 from the outer periphery. A pair of internally threaded holes 22a, 22a that are axially separated are formed in a part of the support portion 22, and pins 24 are screwed into these internally threaded holes 22a, 22a respectively. Moreover, a pair of pins 24, 24 fix the probe portion 21 and the support portion 22. Therefore, when the support portion 22 slides relative to the sliding hole 14, the probe portion 21 also slides integrally. The pair of pins 24, 24 protrudes outward from the pair of internally threaded holes 22a, 22a, and the pair of pins 24, 24 contacts the two axial ends of the elongated hole 13e and is restricted from sliding, thus limiting the axial movement distance of the probe body 11.

[0066] The probe body 11, consisting of a probe portion 21 and a support portion 22, is disposed at the front end side in the sliding hole 14. On the other hand, a helical spring 17 is disposed at the base end side in the sliding hole 14. The helical spring 17 extends axially in a manner that abuts against the cover portion 16 fixed to the housing 13 and the probe body 11. As a result, the probe body 11 is subjected to a force relative to the housing 13 toward the front end side by the helical spring 17.

[0067] In this embodiment, the helical spring 17 abuts against the bracket portion 22 located on the outer periphery of the probe body 11. Therefore, it is possible to configure the outer diameter of the helical spring 17 to be approximately equal to the inner diameter of the sliding hole 14, and the helical spring 17 is guided by the sliding hole 14, thereby suppressing the buckling of the helical spring 17 and stabilizing the force.

[0068] Furthermore, a gap exists on the inner diameter side of the helical spring 17, and the cable 25 of the probe body 11 extends through this gap. This arrangement of the cable 25 in the dead zone on the inner diameter side of the helical spring 17 contributes to the miniaturization of the probe 10.

[0069] Figure 6 It is a cross-sectional view showing the state in which the probe is in perpendicular contact with the outer track surface. Figure 7 Is Figure 6 The diagram viewed along the direction marked VII. Figure 8 yes Figure 6 Sectional views from VIII 1 to VIII 1 or from VIII 2 to VIII 2. Figure 9 yes Figure 7 An enlarged view of the probe in the image.

[0070] like Figures 4-9 As shown, a contact portion 15 is provided at the front end 13b of the generally cuboid-shaped housing 13, capable of abutting against the track surface 61 of the outer ring 60, which serves as the surface to be measured. In the description of the embodiment, the track surface 61 of the outer ring 60 is a concave spherical surface. Furthermore, the shape of the track surface 61 is arbitrary; for example, it may be cylindrical. Specifically, as... Figure 7 , Figure 9 As shown, the shape of the contact portion 15 viewed from the axial direction is preferably rectangular, and in the example shown, it is square.

[0071] The contact portion 15 has four protrusions 26 of the same shape that project axially. For example... Figure 9 As shown, the protrusion 26 is approximately cuboid in shape, and the front end face 26a of the protrusion 26 is rectangular. Furthermore, four protrusions 26 are positioned at the vertices of the rectangle of the contact portion 15. Moreover, viewed axially, the four protrusions 26 are respectively located at the vertices of a rectangle R centered on the central axis O1 of the probe body 11. Figure 9 In this design, rectangle R is a square represented by a single-dotted line, formed by connecting the centers of the front end faces 26a of the four protrusions 26. Therefore, the four protrusions 26 are positioned at equal distances from the central axis O1 and are evenly spaced circumferentially relative to the central axis O1. Furthermore, rectangle R does not necessarily have to be a square; for example, it can be a rectangle. Additionally, rectangle R is preferably a shape similar to the rectangle of the contact portion 15.

[0072] like Figures 6-9 As shown, during measurement, it is necessary to maintain the correct orientation of the probe 10, which is perpendicular to the track surface 61 of the outer ring 60. Therefore, the user should ensure that all four protrusions 26 of the touch portion 15 are in contact with the track surface 61 of the outer ring 60.

[0073] Furthermore, the outermost corners 26b of the four protrusions 26 furthest from the central axis O1 of the probe body 11 contact the concave spherical track surface 61. In this way, by making the outermost corners 26b of each of the four protrusions 26 contact the track surface 61, the probe body 11 can be kept perpendicular to the track surface 61, resulting in stable measurement results.

[0074] When all the outer corners 26b of the four protrusions 26 are in contact with the track surface 61, the user can sense that the shaking of the probe 10 being held has been eliminated and the posture of the probe 10 has stabilized. Then, the user presses the switch 30 to start acquiring the measurement signal S1 to determine the fatigue level or remaining life of the bearing.

[0075] Furthermore, when the track surface 61 is a cylindrical shape concentric with the central axis O2 of the outer ring 60, it is necessary to maintain the probe 10 in the correct orientation, perpendicular to the track surface 61, during measurement. In this case, such as Figure 9 As shown, adjust the probe body 11 so that its central axis O1 is perpendicular to the central axis O2 of the outer ring 60. Also, ensure that the two parallel sides r1 and r2 of the rectangle R are parallel to the central axis O2 of the outer ring 60, and that the other two parallel sides r3 and r4 of the rectangle R are perpendicular to the central axis O2 of the outer ring 60. Furthermore, adjust the circumferential side (…). Figure 9 On the upper side) a pair of protrusions 26, 26 are separated from each other in the direction of the central axis O2 of the outer ring 60, and similarly, on the other side circumferentially ( Figure 9 The pair of protrusions 26, 26 on the lower side of the outer ring 60 are also separated from each other in the direction of the central axis O2 of the outer ring 60. Furthermore, the location where the four protrusions 26 contact the track surface 61 differs from the case where the track surface 61 is a concave spherical surface. In the case where the track surface 61 is cylindrical, the four protrusions 26 contact the track surface 61 at the outer circumferential outer edge 26d, including the outer corner 26b.

[0076] Next, the measurement of the track surface 71 formed on the outer circumference of the inner ring 70 will be explained. Figure 10 It is a cross-sectional view showing the state in which the probe is in perpendicular contact with the inner track surface. Figure 11 Is Figure 10 The image is viewed along the direction marked XI. Figure 12 yes Figure 11 XII-XII sectional view. Figure 13 yes Figure 11 XIII-XIII view section. Figure 14 yes Figure 11 An enlarged view of the probe in the image. Figure 15 yes Figure 10 A magnified view of a portion of the image.

[0077] In the example shown, multiple rows of track surfaces 71 and 72 are formed on the outer periphery of the inner ring 70. Track surface 71 is a convex curved surface. Furthermore, the shape of track surface 71 is arbitrary; for example, it can also be cylindrical. Figures 10-15 As shown, during measurement, it is necessary to maintain the correct orientation of the probe 10, which is perpendicular to the track surface 71 of the inner ring 70. Therefore, the user adjusts the orientation of the probe 10 so that all four protrusions 26 of the contact portion 15 are in contact with the track surface 71 of the inner ring 70. Specifically, as... Figure 14 and Figure 15 As shown, adjust the probe body 11 so that the central axis O1 is perpendicular to the normal direction O4 of the contact angle α of the inner ring 70, the two parallel sides r1 and r2 of the four sides forming the rectangle R are parallel to the normal direction O4 of the contact angle α, and the other two parallel sides r3 and r4 of the four sides forming the rectangle R are perpendicular to the normal direction O4 of the contact angle α.

[0078] Here, refer to Figure 15 The normal direction O4 for the contact angle α is explained. Figure 15 In this diagram, α is the contact angle, O3 is the central axis of the inner ring 70, O4 is the normal direction of the contact angle α, and O5 is the contact angle direction. The contact angle α is defined as the "nominal contact angle" in Japanese Industrial Standard JIS B0104-1991 "Rolling Bearing Terminology," and is the angle formed by the plane S orthogonal to the central axis O3 of the inner ring 70 and the contact angle direction O5. The contact angle direction O5 is the direction of the line of action of the load, which is the direction of the force applied to the inner ring 70 by the rolling element (not shown). The normal direction O4 of the contact angle α passes through the track surface 71 and is orthogonal to the contact angle direction O5. Furthermore, when the probe 10 is positioned correctly perpendicular to the track surface 71, the central axis O1 of the probe body 11 is aligned with the contact angle direction O5 and perpendicular to the normal direction O4 of the contact angle α.

[0079] Thus, when the four protrusions 26 come into contact with the track surface 71, as... Figure 14 As shown, protrusions 26 are located in pairs on both sides of the circumference, sandwiched between the contact angle α and the normal direction O4. Furthermore, on one side of the circumference ( Figure 14 On the upper side, a pair of protrusions 26, 26 are separated from each other in the normal direction O4 of the contact angle α. Similarly, on the other side circumferentially ( Figure 14 The pair of protrusions 26, 26 on the lower side of the inner ring are also separated from each other on the normal direction O4 of the contact angle α of the inner ring 70.

[0080] Furthermore, the four protrusions 26 contact the convex curved track surface 71 at their inner corners 26c. The inner corner 26c is one of the four corners of the front end face 26a of the protrusion 26 that is located on the outer side and inward side in the circumferential direction along the normal direction O4 of the contact angle α. In this way, by making the inner corners 26c of each of the four protrusions 26 contact the track surface 71, the probe body 11 can be kept perpendicular to the track surface 71, resulting in stable measurement results.

[0081] When all the inner corners 26c of the four protrusions 26 are in contact with the track surface 71, the user can sense that the shaking of the probe 10 being held has been eliminated and the posture of the probe 10 has stabilized. Then, the user presses the switch 30 to start acquiring the measurement signal S1 to determine the fatigue level or remaining life of the bearing.

[0082] Furthermore, when the track surface 71 is a cylindrical shape concentric with the central axis O3 of the inner ring 70, it is also necessary to maintain the correct posture of the probe 10 perpendicular to the track surface 71 during measurement. In this case, although not specifically illustrated, it is sufficient to adjust the probe body 11 so that its central axis O1 is perpendicular to the central axis O3 of the inner ring 70, the two parallel sides r1 and r2 of the four sides forming the rectangle R are parallel to the central axis O3 of the inner ring 70, and the other two parallel sides r3 and r4 of the four sides forming the rectangle R are perpendicular to the central axis O3 of the inner ring 70. Also, on the circumferential side ( Figure 14 On the upper side) a pair of protrusions 26, 26 are separated from each other in the direction of the central axis O3 of the inner ring 70, and similarly, on the other side circumferentially ( Figure 14 The pair of protrusions 26, 26 on the lower side of the inner ring 70 are also separated from each other in the direction of the central axis O3 of the inner ring 70. Furthermore, the contact points between the four protrusions 26 and the track surface 71 differ from the case where the track surface 71 is a convex spherical surface. In the case where the track surface 71 is cylindrical, the four protrusions 26 are located on the circumferential inner edge 26e including the inner corner 26c (see...). Figure 14 It contacts the track surface 61.

[0083] In the illustrated example, the touch portion 15 is rectangular when viewed from the axial direction, and four protrusions 26 are disposed at the vertices of the rectangle of the touch portion 15. Therefore, the four protrusions 26 can be arranged in the touch portion 15 with good space efficiency, and the distance between adjacent protrusions 26 can be extended to stabilize the posture of the probe 10.

[0084] Furthermore, the shape of the contact portion 15 viewed from the axial direction is not limited to a rectangle; it can be any shape, such as a circle, for ease of manufacturing.

[0085] Furthermore, in the illustrated example, the front end face 26a of the protrusion 26, viewed axially, is rectangular. Therefore, for the track surface 61 of the outer ring 60, where the object being measured is a concave spherical surface, the probe 10's posture can be stably maintained by contacting the outer corner 26b of each of the four protrusions 26 with the track surface 61. Moreover, when the track surface 71 of the inner ring 70, where the object being measured is a convex curved surface, the probe 10's posture can be stably maintained by contacting the inner corner 26c of each of the four protrusions 26 with the object being measured. And, although not specifically illustrated, when the object being measured is a plane, the probe 10's posture can be stably maintained by contacting the entire front end face 26a of the four protrusions 26 with the object being measured.

[0086] Furthermore, the shape of the front end face 26a of the protrusion 26 viewed from the axial direction is not limited to a rectangle; it can be any shape, such as a circle, for ease of manufacturing.

[0087] In the illustrated example, the protrusion 26 is integrally formed with the contact portion 15, but the protrusion 26 can also be a pin separate from the contact portion 15. In this case, the method of fixing the pin constituting the protrusion 26 is arbitrary; for example, methods such as bonding it to the contact portion 15, pressing it in, or screwing it into a hole formed in the contact portion 15 can be used. In this way, by making the protrusion 26 separate, it can be replaced when the protrusion 26 is damaged or worn. Furthermore, appropriate protrusions 26 can be replaced for measurement object surfaces that differ in shape, roughness, and other characteristics.

[0088] As described above, after confirming that the probe 10 is in correct contact with the track surface 61 of the outer ring 60 and the track surface 71 of the inner ring 70, the user presses the switch 30, thereby switching the determination device 1 to the measurement execution state. The inventors of this application conceived of improving operability by allowing the switch 30 to be attached to and detached from the probe 10 according to its usage. For example, when measuring in narrow spaces such as the gap of a bearing, the switch 30 can be removed from the probe 10, resulting in good operability. Furthermore, for example, when supporting the bearing with the left hand while holding the probe 10 with the right hand, it is preferable to install the switch 30 on the probe 10 so that the switch 30 can be pressed with the right hand. Therefore, the structure for allowing the switch 30 to be attached to and detached from the probe 10 will be described in detail below.

[0089] Figure 16 This diagram shows the state when a switch is installed on the probe. Figure 17 This indicates that the switch is turned from... Figure 16 The diagram shows the state of the probe moving towards the front end. Figure 18 This is a three-dimensional view of the switch as seen from the front side. Figure 19 This is a three-dimensional view of the switch as seen from the back side.

[0090] like Figures 16-19 As shown, the switch 30 has a ring portion 31 in a generally circular shape and a main body portion 32 on which a first button 33a, a second button 33b, a third button 33c, and the second button 33b are formed. In the example switch 30 shown, the ring portion 31 and the main body portion 32 are separate parts that can be disassembled and assembled with each other, but the ring portion 31 and the main body portion 32 can also be formed as a single part.

[0091] The ring portion 31 is approximately circular in shape with the central axis P as its center. The ring portion 31 is preferably made of a material capable of elastic deformation, such as resin, rubber, rope, or belt. If the ring portion 31 can elastically deform, it is easy to attach to the probe 10, the user's finger, etc.

[0092] The ring portion 31 includes: a base portion 31a, which has a fixed main body portion 32; and a pair of clamping pieces 31b, 31b, which are respectively connected to the two ends of the base portion 31a and extend around the central axis P in a roughly C-shaped cross section.

[0093] The base portion 31a has an engaging portion formed by protrusions and concavities (not shown) on its surface opposite the main body portion 32. By engaging the engaging portion of the main body portion 32 (not shown) with the engaging portion of the base portion 31a, the ring portion 31 and the main body portion 32 are engaged together and integrated. Furthermore, the engagement between the engaging portion of the ring portion 31 and the engaging portion of the main body portion 32 is not limited to the aforementioned interlocking of protrusions and concavities; for example, it can also be an engagement based on a surface joint, an engagement based on a magnet, or the like.

[0094] A recess 31c is formed at the base end of each clamping piece 31b, facing the inner diameter side, which promotes elastic deformation of the clamping piece 31b. The front ends of a pair of clamping pieces 31b are positioned opposite each other with a gap T between them. By setting the gap T in this way, the ring portion 31 of the switch 30 is formed into a shape in which a portion of its circumference is cut off.

[0095] The probe 10 and the user's finger are inserted into the internal space of the ring 31 between the pair of clamping pieces 31b, 31b. The pair of clamping pieces 31b, 31b elastically clamp the probe 10 and the user's finger. Furthermore, the probe 10 and the like can be inserted into the internal space of the ring 31 through the gap T, so the insertion operation is very simple.

[0096] In particular, since probe 10 has cable 25, it is difficult to remove the ring 31 from the base side without forming a gap T. Figure 16 and Figure 17The upper side of the ring 31 is mounted on the probe 10. However, according to the ring 31 of this embodiment, the cable 25 can pass through the cut-off portion (gap T) of the ring 31, so the ring 31 can be easily fixed to the probe 10.

[0097] The ring portion 31 of the switch 30 is preferably 13mm to 30mm. By setting it to this size, the user can insert the ring portion 31 into their own finger to operate the switch 30.

[0098] The main body 32 is a generally disc-shaped component that houses a battery that supplies power to the main body 32. First and third buttons 33a and 33c are formed on the front side of the main body 32 opposite to the ring portion 31. A second button 33b is located at the center of the front side of the main body 32, and the first button 33a and the third button 33c are located on either side of the central axis P of the second button 33b.

[0099] The pressing direction of the second button 33b in the center is the radial direction Q of the ring 31 about the central axis P (see reference). Figure 16 That is, the pressing direction of the second button 33b only has a radial component parallel to the radial direction Q, and does not have an axial component parallel to the central axis P. Therefore, the surface of the second button 33b is perpendicular to the radial direction Q.

[0100] In contrast, the surfaces of the first buttons 33a and the third buttons 33c on either side of the second button 33b are formed as inclined surfaces that are inclined towards the central axis P relative to the pressing surface of the second button 33b. Therefore, the pressing direction of the first buttons 33a and the third buttons 33c simultaneously has an axial component parallel to the central axis P of the ring portion 31 and a radial component parallel to the radial direction Q. That is, when the first buttons 33a and the third buttons 33c are pressed, they are pressed not only in the radial direction Q but also in the direction of the central axis P. By setting the pressing direction of the first buttons 33a and the third buttons 33c in this way, in situations such as... Figure 16 and Figure 17 With the switch 30 installed on the probe 10, the user can easily press the first button 33a and the third button 33c while holding the probe 10.

[0101] When at least one of the first to third buttons 33a to 33c is pressed, the main body 32 sends a signal to the input section 40 (see reference). Figure 1 The switch 30 transmits a measurement control signal S2 to switch the start and end of acquiring the measurement signal S1 of the impedance detected by the probe 10. At this time, the switch 30 transmits the measurement control signal S2 wirelessly. This avoids interference between the measurement signal S1 of the probe 10, which is transmitted wiredly via cable 25, and the measurement control signal S2 of the switch 30. Furthermore, since the switch 30 is unwired, installation to the probe 10 becomes easier.

[0102] The switch 30, configured as described above, can be detached from and mounted relative to the outer peripheral surfaces 13f and 13d of the housing 13 of the probe 10. Figure 16 and Figure 17 The diagram shows the case where the switch 30 is mounted on the outer peripheral surface 13f of the cylindrical base 13a of the housing 13, but the switch 30 can also be mounted on the outer peripheral surface 13d of the cuboid front end 13b.

[0103] However, users typically hold the base 13a, not the front end 13b. Therefore, to facilitate operation of the switch 30 while holding it, it is preferable to mount the switch 30 on the outer peripheral surface 13f of the base 13a. Furthermore, since the outer peripheral surface 13f of the base 13a is cylindrical, the approximately annular ring 31 of the switch 30 can be easily mounted. On the other hand, if the cross-sectional shape, such as the outer peripheral surface 13d of the front end 13b, is not circular but rectangular, the orientation must be properly adjusted for mounting the switch, complicating the installation process.

[0104] A stepped portion 13c is formed between the outer peripheral surface 13f of the base 13a and the outer peripheral surface 13d of the front end 13b of the shell 13. Figure 17 The diagram shows the contact between the ring portion 31 and the stepped portion 13c. In this way, the axial movement of the switch 30 is restricted by the stepped portion 13c, so that the switch 30 is less likely to deviate when the user operates the switch 30 (especially when the first button 33a is pressed in the direction of the front end of the probe 10), thus improving the ease of use.

[0105] Furthermore, although not specifically illustrated, the step portion is not limited to the step portion 13c shown in the illustration. As long as it can restrict the axial movement of the switch 30, the shape, arrangement, etc. are arbitrary. For example, it can be a step portion composed of a concave portion and a convex portion provided on the outer peripheral surface 13f of the base 13a, or it can be a step portion composed of a concave portion and a convex portion provided on the outer peripheral surface 13f of the front end portion 13b.

[0106] The illustrated example shows an example where the ring portion 31 of the switch 30 can be detached from the probe 10, but the main body portion 32 of the switch 30 can also be detached from the probe 10. That is, the following structure can also be adopted: the ring portion 31 and the main body portion 32 of the switch 30 are separate parts, and the main body portion 32 can be removed from the ring portion 31, so that only the main body portion 32 can be installed on the housing 13 of the probe 10.

[0107] As described above, a locking portion, consisting of protrusions and concavities (not shown), is provided on the surface of the base portion 31a opposite to the main body portion 32. By engaging the locking portion of the main body portion 32 (not shown) with the locking portion of the base portion 31a, the ring portion 31 and the main body portion 32 are engaged and integrated. Therefore, although not specifically shown, if a locking portion consisting of protrusions and concavities similar to those of the base portion 31a is provided on the outer peripheral surfaces 13d and 13f of the probe housing 13, the locking portion of the main body portion 32 of the switch 30 can be engaged with the locking portion of the housing 13. Furthermore, the engagement between the locking portion of the probe housing 13 and the locking portion of the main body portion 32 is not limited to the engagement based on the protrusion-contact shape described above; for example, it can also be an engagement based on a surface joint, an engagement based on a magnet, etc.

[0108] In this way, if the main body 32 of the switch 30 can be detached and reattached relative to the ring portion 31 of the switch 30 and the outer peripheral surfaces 13d and 13f of the housing 13, the processing of the main body 32 having the first to third buttons 33a to 33c becomes easier. Furthermore, for example, the main body 32 can be removed from the ring portion 31 of the user's finger while the ring portion 31 is embedded in the user's finger, and then installed in the housing 13 of the probe 10. Also, the main body 32 can be removed from the housing 13 and installed relative to the ring portion 31 while it remains embedded in the user's finger.

[0109] Furthermore, the present invention is not limited to the embodiments described above, and can be appropriately modified or improved.

[0110] As stated above, the following matters are disclosed in this specification.

[0111] (1) A determination device comprising: a probe that induces eddy currents in a bearing by applying an alternating magnetic field and detects the impedance of the bearing; a switch that sends a measurement control signal to switch the start and end of the acquisition of a measurement signal of the impedance detected by the probe; a fatigue determination unit that determines the fatigue degree or remaining life of the bearing based on the impedance of the bearing, wherein the fatigue determination unit comprises: a determination graph storage unit that stores a determination graph including the relationship between the impedance characteristics of the bearing and the fatigue degree or remaining life of the bearing; a measurement switching unit that switches between a measurement implementation state and a measurement non-implementation state based on the state of the measurement control signal; a data holding unit that holds the measurement signal in the measurement implementation state; an impedance characteristic calculation unit that calculates the impedance characteristics of the bearing based on the held measurement signal; and a determination unit that determines the fatigue degree or remaining life of the bearing based on the impedance characteristics of the bearing and the determination graph, wherein the probe comprises: a probe body that abuts against the measurement object surface of the bearing to detect the impedance of the bearing; a housing that is generally cylindrical and has a hole therein for accommodating the probe body, and the switch being detachable from the housing.

[0112] (2) According to the determination device described in (1), wherein the switch is detachable from the outer peripheral surface of the housing, and the outer peripheral surface of the housing is a cylindrical surface.

[0113] (3) The determining device according to (1), wherein a stepped portion is formed on the outer peripheral surface of the housing.

[0114] (4) The determination device according to any one of (1) to (3), wherein the switch transmits the measurement control signal wirelessly.

[0115] (5) The determining device according to any one of (1) to (4), wherein the switch comprises: a ring portion of approximately annular shape which is detachable from the outer peripheral surface of the housing; and a main body portion having a button that can be pressed by a user.

[0116] (6) According to the determination device described in (5), the inner diameter of the ring portion of the switch is 13mm to 30mm.

[0117] (7) The determination device according to (5) or (6), wherein the ring portion of the switch is made of a material capable of elastic deformation.

[0118] (8) The determining device according to any one of (5) to (7), wherein a circumferential portion of the ring portion of the switch is cut off.

[0119] (9) The determining device according to any one of (5) to (8), wherein the pressing direction of the button of the main body of the switch has an axial component parallel to the central axis of the ring and a radial component parallel to the radial direction about the central axis of the ring.

[0120] (10) The determining device according to any one of (5) to (9), wherein the ring portion and the main body portion of the switch are separate components, and the main body portion can be disassembled and assembled with respect to the outer peripheral surface of the ring portion and the housing, respectively.

[0121] Furthermore, this application is based on Japanese Patent Application No. 2024-036004, filed on March 8, 2024, the contents of which are incorporated herein by reference.

[0122] Explanation of reference numerals in the attached figures

[0123] 1: Judgment device

[0124] 10: Probe

[0125] 11: Probe body

[0126] 13: Shell

[0127] 13a: Base

[0128] 13b: Front end

[0129] 13c: Step section

[0130] 13d: Outer peripheral surface of the front end

[0131] 13e: Elongated aperture

[0132] 13f: Outer peripheral surface of the base

[0133] 13f: Outer peripheral surface of the base

[0134] 14: Sliding hole (hole)

[0135] 14a: Open at the front end

[0136] 14b: Base opening

[0137] 15: Touch area

[0138] 17: Coil spring (force-applying spring)

[0139] 21: Probe section

[0140] 22: Support section

[0141] 22a: Internal threaded hole

[0142] 24: Sales

[0143] 25: Cables

[0144] 26: Protrusion

[0145] 26a: Front end face

[0146] 26b: Outer corner

[0147] 26c: Inner corner

[0148] 26d: Circumferential outer edge

[0149] 26e: Circumferential inner side

[0150] 30: Switch

[0151] 31: Ring section

[0152] 31a: Base portion

[0153] 31b: Clamping plate

[0154] 31c: Concave

[0155] 32: Main body

[0156] 33a: First button

[0157] 33b: Second button

[0158] 33c: Third button

[0159] 40: Input Section

[0160] 50: Fatigue Assessment Department

[0161] 51: Decision graph storage unit

[0162] 53: Measurement Switching Unit

[0163] 55: Data Retention Department

[0164] 57: Impedance Characteristic Calculation Section

[0165] 58: Display Section

[0166] 59: Judgment Department

[0167] 60: Outer ring (bearing)

[0168] 61: Track surface (surface of the object being measured)

[0169] 70: Inner ring (bearing)

[0170] 71: Track surface (surface of the object being measured)

[0171] O1: Central axis of the probe body

[0172] O2: The central axis of the outer ring

[0173] O3: Central axis of the inner ring

[0174] O4: Normal direction of the contact angle

[0175] O5: Contact Angle Direction

[0176] P: The central axis of the switch's ring.

[0177] Q: Radius direction of the switch's ring

[0178] T: Gap

Claims

1. A determination device comprising: a probe that induces eddy current in a bearing by applying an alternating magnetic field, and detects an impedance of the bearing; a switch that transmits a measurement control signal that switches a start and an end of acquisition of a measurement signal of the impedance detected by the probe; a fatigue determination section that determines a fatigue degree or a remaining life of the bearing based on the impedance of the bearing, characterized in that: the fatigue determination section comprises: a determination map storage section that stores a determination map that contains a relationship between an impedance characteristic of the bearing and the fatigue degree or the remaining life of the bearing; a measurement switching section that switches a measurement execution state and a measurement non-execution state based on a state of the measurement control signal; a data holding section that holds the measurement signal in the measurement execution state; an impedance characteristic calculation section that calculates the impedance characteristic of the bearing based on the held measurement signal; and a determination section that determines the fatigue degree or the remaining life of the bearing based on the impedance characteristic of the bearing and the determination map, the probe comprises: a probe main body that detects the impedance of the bearing by abutting against a measurement target surface of the bearing; and a housing that is substantially cylindrical, has a hole that accommodates the probe main body in an inside thereof, and the switch is detachable with respect to the housing.

2. The determination device according to claim 1, characterized in that: the switch is detachable with respect to an outer peripheral surface of the housing, and the outer peripheral surface of the housing is a cylindrical surface.

3. The determination device according to claim 1, characterized in that: a stepped portion is formed in the outer peripheral surface of the housing.

4. The determination device according to claim 1, characterized in that: the switch transmits the measurement control signal in a wireless manner.

5. The determination device according to claim 1, characterized in that: the switch contains: a ring section that is substantially circular ring-shaped, and is detachable with respect to the outer peripheral surface of the housing; and a main body section that is formed with a button that a user can press down.

6. The determination device according to claim 5, characterized in that: an inner diameter of the ring section of the switch is 13 mm to 30 mm.

7. The determination device according to claim 5, characterized in that: the ring section of the switch is composed of a material that can be elastically deformed.

8. The determination device according to claim 5, characterized in that: a part of a circumferential direction of the ring section of the switch is cut out.

9. The determination device according to claim 5, characterized in that: a pressing direction of the button of the main body section of the switch has an axial component that is parallel to a central axis of the ring section and a radial component that is parallel to a radial direction with respect to the central axis of the ring section.

10. The determination device according to claim 5, characterized in that: the ring section and the main body section of the switch are separate components, and the main body section is detachable with respect to the ring section and the outer peripheral surface of the housing, respectively. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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