Motor bearing wear monitoring device, open circuit detection program, open circuit estimation program, and open circuit detection method

Abstract

The presence or absence of a broken wire in the detection coil is safely checked without stopping the canned motor pump. The motor bearing wear monitoring device (5) according to the present invention monitors the wear state of the bearing based on the detection signals of each of the plurality of detection coils (C1~C8) that detect a change in magnetic flux corresponding to a change in the mechanical position of the rotor (36) relative to the stator (37). The motor bearing wear monitoring device comprises a threshold value storage unit (53b), an acquisition unit (532) that acquires a radial path signal flowing through the radial signal path (L1, L2) and a thrust path signal flowing through the thrust signal path (L3, L4), and a broken wire detection unit (535) that detects the presence or absence of a broken wire in each of the detection coil, the radial signal path, and the thrust signal path. The broken wire detection unit detects the presence or absence of a broken wire in the corresponding detection coil, the radial signal path, and the thrust signal path based on the voltage values ​​of each of the radial path signal and the thrust path signal, the radial threshold value, and the thrust threshold value.

Description

Technology Field

[0001] The present invention relates to a motor bearing wear monitoring device, a wire breakage detection program, a wire breakage estimation program, and a wire breakage detection method. Background Technology

[0002] A canned motor pump has a structure in which the pump and motor are integrated and there is no leakage of the handling fluid. Generally, the rotating structural parts of a canned motor pump (rotor, rotating shaft, bearings, and impeller) are sealed in a can filled with the handling fluid. Therefore, the internal structure of the canned motor pump cannot be visually monitored from the outside. Accordingly, in order to efficiently operate a canned motor pump having such a structure, a device for monitoring the wear condition of the bearings (hereinafter referred to as the "monitoring device") is used (for example, see Patent Document 1). Prior art literature

[0003] [Patent Document 1] Japanese Published Patent No. 2013-78170 The problem to be solved

[0004] The monitoring device disclosed in Patent Document 1 monitors radial and axial displacement of the rotor (rotation axis) caused by bearing wear by measuring changes in magnetic flux during rotor rotation using a detection coil. The detection coil is embedded and mounted at both ends of the stator in the longitudinal direction. Therefore, the presence or absence of a broken wire in the detection coil cannot be visually confirmed from the outside of the canned motor pump and can only be confirmed electrically. Electrical verification requires access to the terminal block. However, from the perspective of worker safety, it is difficult to access the terminal block of a canned motor pump in operation, and exposure of the terminal block is also restricted in explosion-proof environments. Therefore, the canned motor pump must be stopped for electrical verification, but this is not easy because stopping the canned motor pump causes the manufacturing equipment or factory facilities to stop.

[0005] The present invention aims to provide a motor bearing wear monitoring device, a wire breakage detection program, a wire breakage estimation program, and a wire breakage detection method that can safely check for the presence or absence of a wire breakage in a detection coil without stopping a canned motor pump. means of solving the problem

[0006] A motor bearing wear monitoring device according to one embodiment of the present invention is a motor bearing wear monitoring device that monitors the wear state of a bearing supporting the rotation axis of a rotor based on detection signals of each of a plurality of detection coils that detect a change in magnetic flux corresponding to a change in the mechanical position of the rotor relative to the stator of a motor of a canned motor pump, wherein the plurality of detection coils includes at least one group of radial detection coils that detect the change in magnetic flux in the radial direction of the rotation axis and at least one group of thrust detection coils that detect the change in magnetic flux in the thrust direction of the rotation axis, wherein in the thrust direction, the radial detection coil and the thrust detection coil are disposed at the end of the stator on one side or the other side, wherein the radial detection coil is electrically connected to a radial signal path through which a radial composite signal, formed by synthesizing the detection signals of each of the radial detection coils, flows, and the thrust detection coil is electrically connected to a thrust signal path through which a thrust composite signal, formed by synthesizing the detection signals of each of the thrust detection coils, flows, and is smaller than the voltage value of the radial composite signal. The apparatus comprises a threshold storage unit storing a set radial threshold value and a thrust threshold value set to be smaller than the voltage value of the thrust composite signal, an acquisition unit acquiring a radial path signal flowing through the radial signal path and a thrust path signal flowing through the thrust signal path, and a disconnection detection unit detecting whether the detection coil, the radial signal path, and the thrust signal path are each disconnected, wherein when the detection coil, the radial signal path, and the thrust signal path are not disconnected, the radial composite signal flows through the radial signal path as the radial path signal, and the thrust composite signal flows through the thrust signal path as the thrust path signal.The above-described open circuit detection unit detects whether there is an open circuit between the radial detection coil and the radial signal path based on the voltage value of the radial path signal and the radial threshold value, and detects whether there is an open circuit between the thrust detection coil and the thrust signal path based on the voltage value of the thrust path signal and the thrust threshold value.

[0007] A motor bearing wear monitoring device according to one embodiment of the present invention is a motor bearing wear monitoring device that monitors the wear state of a bearing supporting the rotation axis of a rotor based on detection signals of each of a plurality of detection coils that detect a change in magnetic flux corresponding to a change in the mechanical position of the rotor relative to the stator of a motor of a canned motor pump, wherein the plurality of detection coils include one group of radial detection coils that detect the change in magnetic flux in the radial direction of the rotation axis and one group of thrust detection coils that detect the change in magnetic flux in the thrust direction of the rotation axis, wherein in the thrust direction, the radial detection coil and the thrust detection coil are disposed at the end of the stator on one side or the other side, wherein the radial detection coil is electrically connected to a radial signal path through which a radial composite signal, formed by synthesizing the detection signals of each of the radial detection coils, flows, and the thrust detection coil is electrically connected to a thrust signal path through which a thrust composite signal, formed by synthesizing the detection signals of each of the thrust detection coils, flows, and wherein the maximum value among the voltage values ​​of the radial composite signal A voltage value storage unit that updates and stores a thrust maximum voltage value which is the maximum value among the radial maximum voltage value and the voltage value of the thrust composite signal; an acquisition unit that acquires a radial path signal flowing through the radial signal path, a thrust path signal flowing through the thrust signal path, the radial maximum voltage value, and the thrust maximum voltage value; a learning model storage unit that stores a machine-learned radial learning model to estimate whether there is a disconnection between the radial detection coil and the radial signal path when the voltage value of the radial path signal and the radial maximum voltage value are input, and a machine-learned thrust learning model to estimate whether there is a disconnection between the thrust detection coil and the thrust signal path when the voltage value of the thrust path signal and the thrust maximum voltage value are input, and the detection coil,A disconnection estimation unit is provided to estimate whether there is a disconnection in each of the above-mentioned radial signal path and the above-mentioned thrust signal path, and when the detection coil, the above-mentioned radial signal path, and the above-mentioned thrust signal path are not disconnected, the radial composite signal flows through the radial signal path as the radial path signal, and the thrust composite signal flows through the thrust signal path as the thrust path signal, and the disconnection estimation unit inputs the voltage value of the radial path signal and the radial maximum voltage value into the radial learning model to estimate whether there is a disconnection in each of the radial detection coil and the radial signal path, and inputs the voltage value of the thrust path signal and the thrust maximum voltage value into the thrust learning model to estimate whether there is a disconnection in each of the thrust detection coil and the thrust signal path.

[0008] A wire breakage detection program according to one embodiment of the present invention enables a computer to function as a motor bearing wear monitoring device according to the first embodiment.

[0009] A wire breakage estimation program according to one embodiment of the present invention enables a computer to function as a motor bearing wear monitoring device according to the second embodiment.

[0010] A wire break detection method according to one embodiment of the present invention is a wire break detection method executed by a motor bearing wear monitoring device that monitors the wear state of a bearing supporting the rotation axis of a rotor based on detection signals of each of a plurality of detection coils that detect a change in magnetic flux corresponding to a change in the mechanical position of a rotor relative to a stator of a canned motor pump, wherein the plurality of detection coils includes one group of radial detection coils that detect the change in magnetic flux in the radial direction of the rotation axis and one group of thrust detection coils that detect the change in magnetic flux in the thrust direction of the rotation axis, wherein in the thrust direction, the radial detection coil and the thrust detection coil are disposed at the end of the stator on one side or the other side, wherein the radial detection coil is electrically connected to a radial signal path through which a radial composite signal, formed by synthesizing the detection signals of each of the radial detection coils, flows, and the thrust detection coil is electrically connected to a thrust signal path through which a thrust composite signal, formed by synthesizing the detection signals of each of the thrust detection coils, flows, and wherein the motor bearing wear monitoring device A threshold storage unit storing a radial threshold value set to be smaller than the voltage value of a radial composite signal and a thrust threshold value set to be smaller than the voltage value of the thrust composite signal, wherein when the detection coil, the radial signal path, and the thrust signal path are each not disconnected, the radial composite signal flows through the radial signal path as a radial path signal and the thrust composite signal flows through the thrust signal path as a thrust path signal, and the disconnection detection method comprises an acquisition step in which the motor bearing wear monitoring device acquires the radial path signal from the radial signal path and acquires the thrust path signal from the thrust signal path, andThe motor bearing wear monitoring device includes a breakage detection step of detecting the breakage of the radial detection coil and the radial signal path, respectively, based on the voltage value of the radial path signal and the radial threshold value, and detecting the breakage of the thrust detection coil and the thrust signal path, respectively, based on the voltage value of the thrust path signal and the thrust threshold value. Effects of the invention

[0011] According to the present invention, the presence or absence of a broken wire in the detection coil can be safely checked without stopping the canned motor pump. Brief explanation of the drawing

[0012] [Fig. 1] This is a side view of a canned motor pump. [Fig. 2] This is a schematic cross-sectional view showing the longitudinal section of the motor part equipped with the canned motor pump of Fig. 1. [Fig. 3] This is a schematic enlarged cross-sectional view of part A of the motor section of Fig. 2. [Fig. 4] This is a functional block diagram showing an embodiment of a motor bearing wear monitoring device according to the present invention. [Fig. 5] This is a schematic perspective view of a stator core showing the arrangement of detection coils equipped in the motor bearing wear monitoring device of Fig. 4. [Fig. 6] This is an enlarged perspective view of part B of Fig. 5. [Fig. 7] This is a schematic diagram showing an example of a detection signal output by the detection coil of Fig. 5. [Fig. 8] This is a schematic diagram showing an example of information stored in the RAM of the motor bearing wear monitoring device of Fig. 4. [Fig. 9] This is a schematic diagram showing an example of the appearance of the display unit equipped with the motor bearing wear monitoring device of Fig. 4. [Fig. 10] This is a functional block diagram of the offset processing unit equipped with the motor bearing wear monitoring device of Fig. 4. [Fig. 11] This is a flowchart showing an example of the operation of the motor bearing wear monitoring device of Fig. 4. [Fig. 12] This is a flowchart showing an example of the update processing included in the operation of Fig. 11. [Fig. 13] This is a flowchart showing an example of a radial-side open circuit detection process included in the operation of Fig. 11. [Fig. 14] This is a flowchart showing an example of thrust-side disconnection detection processing included in the operation of Fig. 11. [Fig. 15] This is a flowchart showing an example of a wear amount detection process included in the operation of Fig. 11. [Fig. 16] This is a functional block diagram showing another embodiment of a motor bearing wear monitoring device according to the present invention. [Fig. 17] This is a schematic diagram showing an example of information stored in a storage unit equipped with the motor bearing wear monitoring device of Fig. 16. [Fig. 18] This is a flowchart showing an example of the operation of the motor bearing wear monitoring device of Fig. 16. [Fig. 19] This is a flowchart showing an example of the radial-side single-line estimation process included in the operation of Fig. 18. [Fig. 20] This is a flowchart showing an example of thrust-side single-line estimation processing included in the operation of Fig. 18. Specific details for implementing the invention

[0013] The present invention enables the detection coil and its signal path to be safely checked for disconnection without stopping the canned motor pump by providing a motor bearing wear monitoring device for a canned motor pump with a function to automatically detect disconnection of the detection coil and its signal path. Details of each term will be described later.

[0014] Embodiments of a motor bearing wear monitoring device according to the present invention (hereinafter referred to as "the device"), a wire breakage detection program according to the present invention (hereinafter referred to as "the detection program"), a wire breakage estimation program according to the present invention (hereinafter referred to as "the estimation program"), and a wire breakage detection method according to the present invention (hereinafter referred to as "the detection method") are described below. In the following description, each drawing is referenced as appropriate. Identical members and elements in each drawing are given the same reference numerals, and redundant descriptions are omitted. Additionally, the dimensional ratios of each element may be exaggerated for convenience of explanation and are not limited to the ratios shown in each drawing.

[0015] ●Canned Motor Pump●

[0016] ● Components of a Candle Motor Pump

[0017] Figure 1 is a side view of a canned motor pump.

[0018] For convenience of explanation, the drawing shows the upper half of the canned motor pump (1) in cross-sectional view.

[0019] A canned motor pump (1) (hereinafter simply referred to as "pump (1)") has a structure that prevents leakage of the handling liquid and is a pump used particularly for transporting high-temperature liquids or liquids of high risk (e.g., explosive, flammable, or toxic liquids). The pump (1) is equipped with a pump section (2), a motor section (3), an adapter (4), and the present device (5).

[0020] The configuration of the pump (1), the pump section (2), the motor section (3), and the adapter (4) is common to the configuration of a known canned motor pump. Therefore, in the following description, the configuration of the pump section (2), the motor section (3), and the adapter (4) is described only in a general manner and a detailed description is omitted.

[0021] In the following description, "front direction" is the direction (forward) in which the pump unit (2) is located relative to the motor unit (3), and "rear direction" is the direction (rear) in which the motor unit (3) is located relative to the pump unit (2).

[0022] The pump unit (2) sucks in and discharges the handling liquid. The pump unit (2) is equipped with a housing (20), an impeller (21), a pump room (22), a suction pipe section (23), and a discharge pipe section (24). The housing (20) forms a pump room (22) that accommodates the impeller (21), a suction pipe section (23) which is a path for the handling liquid sucked into the pump room (22), and a discharge pipe section (24) which is a path for the handling liquid discharged from the pump room (22). The pump room (22) is connected to the suction pipe section (23) and the discharge pipe section (24).

[0023] The motor unit (3) rotates the impeller (21) by driving under predetermined driving conditions (e.g., 200V, 60Hz). The motor unit (3) is equipped with a housing (30), a rotating shaft (31), two bearings (32, 33), two thrust washers (34, 35), a rotor (36), a stator (37), a can (38), and a terminal (39). The motor unit (3) is an example of a motor in the present invention.

[0024] Figure 2 is a schematic cross-sectional view showing the longitudinal section of the motor part (3).

[0025] Figure 3 is a schematic enlarged cross-sectional view of part A of the motor part (3) of Figure 2.

[0026] Figure 1 is appropriately referenced in the following description.

[0027] The housing (30) hermetically accommodates the stator (37) and the can (38).

[0028] The rotating shaft (31) rotates by the rotation of the rotor (36) and transmits rotational power to the impeller (21). The shape of the rotating shaft (31) is cylindrical. The rotating shaft (31) is inserted through the rotor (36) and fixed to the rotor (36). The front end of the rotating shaft (31) protrudes into the pump chamber (22), and the impeller (21) is mounted on the front end. The rotating shaft (31) is equipped with cylindrical sleeves (31a, 31b) that protect the front and rear parts of the rotating shaft (31).

[0029] In the following description, "thrust direction" is the axial direction of the rotation axis (31), "radial direction" and "radial direction" are the radial direction of the rotation axis (31), and "circumferential direction" is the circumferential direction of the rotation axis (31).

[0030] A bearing (32) is positioned in the front direction of the rotor (36) to rotatably support the rotation axis (31). A bearing (33) is positioned in the rear direction of the rotor (36) to rotatably support the rotation axis (31). The bearings (32, 33) are, for example, sliding bearings. A thrust washer (34) is mounted between the bearing (32) and the rotor (36) of the rotation axis (31) to restrict movement of the rotation axis (31) in the front direction. A thrust washer (35) is mounted between the bearing (33) and the rotor (36) of the rotation axis (31) to restrict movement of the rotation axis (31) in the rear direction.

[0031] A gap of length Lx1 is formed between the bearing (32, 33) and the thrust washer (34, 35). A gap of length Lx2 is formed between the bearing (32, 33) and the sleeve (31a, 31b).

[0032] The rotor (36) rotates by the rotating magnetic field generated in the stator (37). The shape of the rotor (36) is cylindrical. The rotor (36) is provided with a plurality (28 in this embodiment) rod-shaped rotor bars (36a) that are embedded at equal intervals on the outer circumference of the rotor (36) in the circumferential direction.

[0033] The stator (37) generates a rotating magnetic field that rotates the rotor (36). The shape of the stator (37) is approximately cylindrical. The stator (37) has a stator core (37a) and a plurality of motor windings (37b).

[0034] The stator core (37a) supports the motor winding (37b). The shape of the stator core (37a) is cylindrical. The stator core (37a) has a plurality of teeth (37c) (see FIG. 6; the same applies hereinafter).

[0035] The teeth (37c) form a slot (37d) through which the motor winding (37b) is inserted and passed (see FIG. 6; the same applies hereinafter). In the circumferential direction, the teeth (37c) are arranged at equal intervals on the inner circumference of the stator core (37a). The motor winding (37b) is inserted and passed through the slot (37d) and is connected to a power supply (not shown), such as an inverter, through terminal terminals (39).

[0036] The can (38) watertightly accommodates the rotating shaft (31), bearings (32, 33), thrust washers (34, 35), and rotor (36). The shape of the can (38) is cylindrical. A portion of the handling liquid introduced from the suction pipe section (23) is introduced into the can (38) and used to cool the bearings (32, 33) and the motor section (3), and is discharged through the discharge pipe section (24).

[0037] The adapter (4) is connected to the rear end of the pump unit (2) and the front end of the motor unit (3) to connect the pump unit (2) and the motor unit (3).

[0038] The device (5) monitors the wear condition of the bearings (32, 33) supporting the rotation shaft (31) by detecting a change in magnetic flux corresponding to a change in the mechanical position of the rotor (36) relative to the stator (37). The specific configuration of the device (5) will be described later.

[0039] ● Motor bearing wear monitoring device (1) ●

[0040] ● Configuration of the motor bearing wear monitoring device (1)

[0041] Next, the configuration of the device (5) is described below. In the following description, FIGS. 1 to 3 are appropriately referenced.

[0042] FIG. 4 is a functional block diagram showing an embodiment of the device (5).

[0043] The device (5) comprises eight detection coils (C1, C2, C3, C4, C5, C6, C7, C8), a connection unit (50), two common paths (Lc1, Lc2), six signal paths (L11, L12, L13, L14, L15, L16), four signal processing circuits (51a, 51b, 51c, 51d), an A / D converter (52), a control unit (53), a storage unit (54), a display unit (55), and an offset processing unit (56). The A / D converter (52) and the control unit (53) are implemented, for example, by a microcomputer.

[0044] FIG. 5 is a schematic perspective view of a stator core (37a) showing the arrangement of detection coils (C1 to C8).

[0045] Figure 6 is an enlarged perspective view of part B of Figure 5.

[0046] The detection coils (C1~C8) detect a change in magnetic flux corresponding to a change in the position (displacement) of the rotor (36) relative to the stator (37), and generate and output a detection signal (induced current) indicating the change in magnetic flux. The rotor (36) is displaced in the radial direction along with the rotation axis (31) according to the amount of wear in the radial direction of the bearings (32, 33), and is displaced in the thrust direction along with the rotation axis (31) according to the amount of wear in the thrust direction of the bearings (32, 33). That is, the amount of displacement of the rotor (36) can be considered as the amount of wear of the bearings (32, 33). Therefore, the device (5) can detect the amount of wear of the bearings (32, 33) by detecting the amount of displacement of the rotor (36) using the detection coils (C1~C8). The shape of the detection coils (C1~C8) is a flat bobbin type. The detection coils (C1~C8) are fitted into notches (37e) formed in the teeth (37c) of the front and rear ends of the stator (37).

[0047] In the circumferential direction, detection coils (C1 to C4) are mounted at equal intervals (90° intervals) on the front end of the tooth (37c) of the stator (37). In the circumferential direction, detection coil (C1) is positioned to face detection coil (C3) at a position of "180°", and detection coil (C2) is positioned to face detection coil (C4) at a position of "180°". Meanwhile, in the circumferential direction, detection coils (C5 to C8) are mounted at equal intervals (90° intervals) on the rear end of the tooth (37c) of the stator (37). In the circumferential direction, detection coil (C5) is positioned to face detection coil (C7) at a position of "180°", and detection coil (C6) is positioned to face detection coil (C8) at a position of "180°". That is, in the radial direction, the detection coils (C1, C2, C5, C6) are arranged to face the corresponding detection coils (C3, C4, C7, C8).

[0048] Meanwhile, in the present invention, the detection coils (C1, C2, C5, C6) are arranged to face the corresponding detection coils (C3, C4, C7, C8), and their positional relationship is not limited to an exact "180°" position. That is, for example, due to manufacturing errors or the shape of the stator (37), the positional relationship in the circumferential direction may differ from "180°" by a few degrees (e.g., 1° to 5°).

[0049] Additionally, in the present invention, the angle between the detection coil (C1) (detection coil (C3)) and the detection coil (C2) (detection coil (C4)) in the circumferential direction can be appropriately set between 0° and 180° and is not limited to 90°. That is, for example, the detection coil (C2) in the circumferential direction can be placed at the same position (0°) as the detection coil (C1). In this case, the detection coil (C2) in the axial direction is placed parallel to the rear direction (or front direction) of the detection coil (C1). This arrangement is the same for the detection coil (C5) (detection coil (C7)) and the detection coil (C6) (detection coil (C8)).

[0050] Figure 7 is a schematic diagram showing an example of a detection signal.

[0051] The detection signals of the detection coils (C1 to C8) include a waveform corresponding to a change in the main magnetic flux of the motor unit (3) (hereinafter referred to as the "fundamental component") and a waveform corresponding to a change in magnetic flux generated by the induced current flowing through the rotor bar (36a) of the rotor (36) (hereinafter referred to as the "harmonic component"). The fundamental component is generated by the driving voltage of the motor unit (3), and its frequency is the same as the driving frequency of the driving voltage. The harmonic component is generated by the induced current flowing through the rotor bar (36a), and its frequency is determined by the rotation of the rotor (36) and the number of rotor bars (36a). That is, for example, under the following conditions (driving frequency: 60Hz, number of rotor bars (36a): 28), each of the detection coils (C1 to C8) detects a change in magnetic flux caused by the rotor bar (36a) 28 times while the rotor (36) rotates once. Therefore, the frequency of the harmonic component becomes "60Hz x 28 = 1.68kHz". In this way, the fundamental component is determined based on the driving frequency, and the harmonic component is determined according to the rotation of the rotor (36), the driving frequency, and the number of rotor bars (36a).

[0052] In the following description, Figures 3 to 5 are mainly referred to.

[0053] The detection coils (C1, C3, C5, C7) detect the amount of radial displacement of the rotor (36) (i.e., the amount of radial wear of the bearings (32, 33)) by detecting a change in magnetic flux corresponding to the radial displacement of the rotor (36) as the gap (L2) between the bearings (32, 33) and the sleeves (31a, 31b) widens. The detection coil (C1) is electrically connected to the common path (Lc1) and the detection coil (C3). The detection coil (C3) is electrically connected to the signal path (L11) through the connection part (50). The detection coils (C1, C3) form a group of radial detection coils and are connected in series so that their respective detection signals cancel each other out. The detection coil (C5) is electrically connected to the common path (Lc2) and the detection coil (C7). The detection coil (C7) is electrically connected to the signal path (L12) through the connection part (50). The detection coils (C5, C7) constitute another group of radial detection coils and are connected in series so that their respective detection signals cancel each other out. The detection coils (C1, C3, C5, C7) are examples of radial detection coils in the present invention. The detection coils (C1, C3) are examples of first radial detection coils in the present invention, and the detection coils (C5, C7) are examples of second radial detection coils in the present invention.

[0054] When the front side of the rotor (36) is displaced in a radial direction from its initial position, the signal level of the harmonic component increases on the side of the group of detection coils (C1, C3) where the rotor (36) is moving closer (e.g., detection coil (C1)), and decreases on the side where the rotor (36) is moving away (e.g., detection coil (C3)). At this time, since the relative distance of the rotor (36) to the detection coils (C1, C3) is the same, the amount of increase in the signal level is equal to the amount of decrease. Meanwhile, the signal level of the fundamental component does not increase or decrease. Therefore, when the detection signals of each of the detection coils (C1, C3) are combined to take (generate) the difference, the difference in the signal level of the harmonic component in the combined signal (hereinafter referred to as the "combined signal (S13)") increases with the increase in the amount of displacement. By this difference, the amount of radial displacement of the front side of the rotor (36) can be detected. That is, the difference represents the amount of radial wear of the bearing (32), and the value of the difference is expressed as a voltage value. Likewise, in the composite signal of the detection signals of each detection coil (C5, C7) (hereinafter referred to as the "composite signal (S57)"), the difference in the signal level of the harmonic component increases with increasing displacement. By this difference, the amount of radial displacement of the rear side of the rotor (36) can be detected. That is, the difference represents the amount of radial wear of the bearing (33), and the value of the difference is expressed as a voltage value. Therefore, for example, when there is no radial displacement of the rotor (36), the fundamental component and the harmonic component in each composite signal (S13, S57) cancel each other out, and theoretically, the voltage value becomes "0". Meanwhile, when there is a radial displacement of the rotor (36), the difference of the harmonic component in each composite signal (S13, S57) increases according to the amount of displacement, and the voltage value increases according to the difference.In addition, since the detection coils (C1, C3) are independent of the detection coils (C5, C7), uneven wear (a state where one side is more worn than the other) of the bearings (32, 33) can be detected by comparing the values ​​of each of the composite signals (S13, S57). The composite signal (S13) is an example of a radial composite signal and a first composite signal in the present invention, and the composite signal (S57) is an example of a radial composite signal and a second composite signal in the present invention.

[0055] The detection coils (C2, C4, C6, C8) can detect the amount of thrust direction displacement of the rotor (36) (i.e., the amount of thrust direction wear of the bearings (32, 33)) by detecting a change in magnetic flux corresponding to the thrust direction displacement of the rotor (36) as the gap (L1) between the bearings (32, 33) and the thrust washer (34, 35) widens. The detection coil (C2) is electrically connected to the common path (Lc2) and the detection coil (C4). The detection coil (C4) is electrically connected to the signal path (L13) through the connection part (50). The detection coils (C2, C4) constitute a group of thrust detection coils and are connected in series so that their detection signals overlap. Accordingly, the detection signals from each of the detection coils (C2, C4) are combined so that they overlap to generate a composite signal (S24). The detection coil (C6) is electrically connected to the common path (Lc2) and the detection coil (C8). The detection coil (C8) is electrically connected to the signal path (L14) through the connection part (50). The detection coils (C6, C8) constitute another group of thrust detection coils and are connected in series so that their detection signals overlap. Accordingly, the detection signals from each of the detection coils (C6, C8) are combined so that they overlap to generate a composite signal (S68). The detection coils (C2, C4, C6, C8) are examples of thrust detection coils in the present invention. The detection coils (C2, C4) are examples of first thrust detection coils in the present invention, and the detection coils (C6, C8) are examples of second thrust detection coils in the present invention. The composite signal (S24) is an example of a thrust composite signal and a third composite signal in the present invention, and the composite signal (S68) is an example of a thrust composite signal and a fourth composite signal in the present invention.

[0056] When the rotor (36) is displaced from its initial position toward the rear, the overlap between the detection coils (C2, C4) and the front end (end ring) of the rotor (36) in the thrust direction hardly changes, but the overlap between the detection coils (C6, C8) and the rear end (end ring) of the rotor (36) decreases. As a result, the signal level of the fundamental component of the composite signal (S24) hardly changes, but the signal level of the fundamental component of the composite signal (S68) decreases. Similarly, when the rotor (36) is displaced from its initial position toward the front, the signal level of the fundamental component of the composite signal (S68) hardly changes, but the signal level of the fundamental component of the composite signal (S24) decreases. Therefore, the amount of displacement of the rotor (36) in the thrust direction can be detected by the difference between the composite signal (S24) and the composite signal (S68). That is, the difference represents the amount of thrust direction displacement of the rotor (36), i.e., the amount of thrust direction wear of the bearings (32, 33), and the value of the difference is expressed as a voltage value. Thus, for example, when there is no thrust direction displacement of the rotor (36), the fundamental component and the harmonic component in the difference cancel each other out, and theoretically, the voltage value becomes “0”. On the other hand, when there is thrust direction displacement of the rotor (36), the signal level of the fundamental component of the composite signal on one side (e.g., composite signal (S24)) decreases according to the amount of displacement, and the signal level of the fundamental component of the composite signal on the other side (e.g., composite signal (S68)) hardly changes. Therefore, the difference value (voltage value) of the fundamental component in the signal representing the difference increases according to the amount of displacement. In addition, by comparing the magnitudes of the composite signals (S24, S68), the direction of displacement in the thrust direction can be detected.

[0057] The connection part (50) is an interface to which detection coils (C1~C8) are connected. A common path (Lc1, Lc2), detection coils (C3, C7, C4, C8), and signal paths (L11~L14) are connected to the connection part (50). The common path (Lc1, L2) is connected to ground through the connection part (50).

[0058] Signal processing circuits (51a to 51d) are connected to a group of corresponding detection coils (C1 to C8) and perform a predetermined signal processing (rectification, AC-DC conversion) on the corresponding composite signals (S13, S57, S24, S68) to convert the composite signals (S13, S57, S24, S68) from AC to DC. The signal processing circuits (51a to 51d) are composed of, for example, a filter circuit, a rectifier circuit, and an integrator circuit. The signal processing circuit (51a) is connected to a signal path (L11) and converts the composite signal (S13) from AC to DC. The composite signal (S13) converted to DC is input to an A / D converter (52) through the signal path (L11). The signal processing circuit (51b) is connected to a signal path (L12) and converts the composite signal (S57) from AC to DC. The composite signal (S57) converted to DC is input to the A / D converter (52) via the signal path (L12). The signal processing circuit (51c) is connected to the signal path (L13) and converts the composite signal (S24) from AC to DC. The composite signal (S24) converted to DC is input to the A / D converter (52) via the signal path (L13) and is also input to the offset processing unit (56) via the signal path (L15). The signal processing circuit (51d) is connected to the signal path (L14) and converts the composite signal (S68) from AC to DC. The composite signal (S68) converted to DC is input to the A / D converter (52) via the signal path (L14) and is also input to the offset processing unit (56) via the signal path (L16).

[0059] The common path (Lc1), the connection part (50), the signal path (L11), and the signal processing circuit (51a) are electrically connected to the detection coils (C1, C3) and form a first path (L1) through which a composite signal (S13) flows. The common path (Lc1), the connection part (50), the signal path (L12), and the signal processing circuit (51b) are electrically connected to the detection coils (C5, C7) and form a second path (L2) through which a composite signal (S57) flows. The common path (Lc2), the connection part (50), the signal path (L13), and the signal processing circuit (51c) are electrically connected to the detection coils (C2, C4) and form a third path (L3) through which a composite signal (S24) flows. The common path (Lc2), the connection part (50), the signal path (L14), and the signal processing circuit (51d) are connected to the detection coils (C6, C8) and form a fourth path (L4) through which a composite signal (S68) flows. The first path (L1) and the second path (L2) are examples of radial signal paths in the present invention, and the third path (L3) and the fourth path (L4) are examples of thrust signal paths in the present invention. That is, the radial signal path includes the first path (L1) and the second path (L2), and the thrust signal path includes the third path (L3) and the fourth path (L4).

[0060] The A / D converter (52) converts the analog signal input from each of the signal processing circuits (51a to 51d), the arithmetic circuit (56c) and the difference absolute value conversion circuit (56d) described later into a digital signal and outputs it to the control unit (53).

[0061] The control unit (53) controls the operation of the entire device (5). The control unit (53) is composed of a processor, such as a CPU (Central Processing Unit) (53a), volatile memory, such as a RAM (Random Access Memory) (53b) that functions as a work area of ​​the CPU (53a), and non-volatile memory, such as a ROM (Read Only Memory) (53c) that stores various information, such as the detection program or other control programs (e.g., a wear amount detection program). The control unit (53) is equipped with a first acquisition unit (530), a wear amount detection unit (531), a second acquisition unit (532), an update unit (533), a threshold value setting unit (534), a disconnection detection unit (535), and a display control unit (536). The RAM (53b) is an example of a threshold value storage unit and a voltage value storage unit in the present invention. The wear amount detection program is a program required for the execution of the wear amount detection processing (ST4: see FIG. 15) described later.

[0062] In the control unit (53), the detection program is operated, and the detection program cooperates with the hardware resources of the device (5) to realize the detection method described below. Additionally, by executing the detection program on the processor (CPU (53a)) constituting the control unit (53), the detection program can cause the processor to function as a second acquisition unit (532), an update unit (533), a threshold setting unit (534), a disconnection detection unit (535), and a display control unit (536), thereby enabling the processor to execute the detection method. Furthermore, by executing the detection program and the wear amount detection program on a computer, the detection program and the wear amount detection program can cause the computer to function as the device (5).

[0063] In addition, the detection program in this invention may be stored in a storage unit (54). Furthermore, the detection program may be stored in an installable file format or an executable file format on a non-transient storage medium (e.g., CD (Compact Disc), DVD (Digital Versatile Disc), USB (Universal Serial Bus) memory, etc.) and provided to the device (5) through a dedicated reading medium.

[0064] The first acquisition unit (530) acquires a signal (difference signal (Sd) described later) representing the difference between the composite signal (S13), the composite signal (S57), the composite signal (S24), and the composite signal (S68). The specific operation of the first acquisition unit (530) will be described later.

[0065] The wear amount detection unit (531) detects the amount of radial direction wear of the bearings (32, 33) by detecting the amount of radial direction displacement of the front and rear sides of the rotor (36) based on the voltage values ​​of each composite signal (S13, S57) acquired by the first acquisition unit (530). In addition, the wear amount detection unit (531) detects the amount of thrust direction wear of the bearings (32, 33) by detecting the amount of thrust direction displacement of the rotor (36) based on the voltage values ​​of the differential signal (Sd). The specific operation of the wear amount detection unit (531) will be described later.

[0066] The second acquisition unit (532) acquires the first maximum voltage value to the fourth maximum voltage value, the first signal (S1), the second signal (S2), the third signal (S3), and the fourth signal (S4), which will be described later. The second acquisition unit (532) is an example of an acquisition unit in the present invention. The specific operation of the second acquisition unit (532) will be described later.

[0067] In addition, in the present invention, the second acquisition part (532) may function as the first acquisition part (530), and the first acquisition part (530) may function as the second acquisition part (532).

[0068] “The first signal (S1)” is a signal flowing through the first path (L1). When the detection coils (C1, C3) and the first path (L1) are not disconnected, the first signal (S1) may include noise components as well as the composite signal (S13). In other words, when the detection coils (C1, C3) and the first path (L1) are not disconnected, the composite signal (S13) flows through the first path (L1) as the first signal (S1). On the other hand, when the detection coils (C1, C3) or the first path (L1) are disconnected, the first signal (S1) may not include the composite signal (S13) and may mainly include noise components. In other words, when the detection coils (C1, C3) and the first path (L1) are disconnected, the noise components may flow through the first path (L1) as the first signal (S1).

[0069] The “noise component” originates from electromagnetic noise from a noise source (e.g., the motor unit (3), the power supply to the motor unit (3), etc.) and is a signal component (waveform) representing noise included in the first signal (S1) to the fourth signal (S4) flowing through the detection coils (C1~C8) and the first path (L1) to the fourth path (L4). There are various causes of the noise component, and the signal level (i.e., voltage value) of the noise component varies depending on the cause and the noise intrusion path.

[0070] “The second signal (S2)” is a signal flowing through the second path (L2). Similar to the first signal (S1), if the detection coils (C5, C7) and the second path (L2) are not disconnected, the composite signal (S57) flows through the second path (L2) as the second signal (S2). Meanwhile, if the detection coils (C5, C7) or the second path (L2) are disconnected, the noise component may flow through the second path (L2) as the second signal (S2).

[0071] The “third signal (S3)” is a signal flowing through the third path (L3). Similar to the first signal (S1), if the detection coils (C2, C4) and the third path (L3) are not disconnected, the composite signal (S24) flows through the third path (L3) as the third signal (S3). Meanwhile, if the detection coils (C2, C4) or the third path (L3) are disconnected, the noise component may flow through the third path (L3) as the third signal (S3).

[0072] “The fourth signal (S4)” is a signal flowing through the fourth path (L4). Similar to the first signal (S1), if the detection coils (C6, C8) and the fourth path (L4) are not disconnected, the composite signal (S68) flows through the fourth path (L4) as the fourth signal (S4). Meanwhile, if the detection coils (C6, C8) or the fourth path (L4) are disconnected, the noise component may flow through the fourth path (L4) as the fourth signal (S4).

[0073] The first signal (S1) and the second signal (S2) are examples of radial path signals in the present invention, and the third signal (S3) and the fourth signal (S4) are examples of thrust path signals in the present invention. That is, the radial path signal includes the first signal (S1) and the second signal (S2), and the thrust path signal includes the third signal (S3) and the fourth signal (S4).

[0074] The update unit (533) updates the first maximum voltage value, the second maximum voltage value, the third maximum voltage value, and the fourth maximum voltage value stored in the RAM (53b). The specific operation of the update unit (533) will be described later.

[0075] “The first maximum voltage value” is the voltage value that becomes the maximum value among the voltage values ​​of the composite signal (S13) obtained from the first path (L1).

[0076] “The second maximum voltage value” is the voltage value that becomes the maximum value among the voltage values ​​of the composite signal (S57) obtained from the second path (L2).

[0077] The “third maximum voltage value” is the voltage value that becomes the maximum value among the voltage values ​​of the composite signal (S24) obtained from the third path (L3).

[0078] “The fourth maximum voltage value” is the voltage value that becomes the maximum value among the voltage values ​​of the composite signal (S68) obtained from the fourth path (L4).

[0079] The first maximum voltage value and the second maximum voltage value are examples of radial maximum voltage values ​​in the present invention, and the third maximum voltage value and the fourth maximum voltage value are examples of thrust maximum voltage values ​​in the present invention. That is, the radial maximum voltage value includes the first maximum voltage value and the second maximum voltage value, and the thrust maximum voltage value includes the third maximum voltage value and the fourth maximum voltage value.

[0080] The threshold setting unit (534) sets the first threshold, second threshold, third threshold, and fourth threshold based on the first maximum voltage value to the fourth maximum voltage value. The set first threshold to fourth thresholds are stored in RAM (53b). Details of the first threshold to fourth thresholds and the specific operation of the threshold setting unit (534) will be described later.

[0081] FIG. 8 is a schematic diagram showing an example of information stored in RAM (53b).

[0082] The same drawing shows that the first maximum voltage value is "V1 max "and, the second maximum voltage value is "V2 max "and, the third maximum voltage value is "V3 max "and, the fourth maximum voltage value is "V4 max "and, the first threshold is "V t1 "and, the second threshold is "V t2 "and, the third threshold is "V t3 "and, the fourth threshold is "V t4 It indicates that. In addition, the drawing indicates that the first maximum voltage value to the fourth maximum voltage value and the first threshold value to the fourth threshold value are stored in RAM (53b).

[0083] In the following description, Fig. 4 is mainly referred to.

[0084] The disconnection detection unit (535) detects whether there is a disconnection in the detection coils (C1~C8) and the first path (L1) ~ fourth path (L4) based on the first signal (S1) ~ fourth signal (S4) and the first threshold value ~ fourth threshold value. The specific operation of the disconnection detection unit (535) will be described later.

[0085] The display control unit (536) controls the display of the display unit (55) based on the amount of wear detected by the wear amount detection unit (531) and the presence or absence of a broken wire detected by the broken wire detection unit (535). The specific operation of the display control unit (536) will be described later.

[0086] The storage unit (54) stores information necessary for the operation of the device (5) (e.g., offset information, first corresponding relationship information, second corresponding relationship information, etc.). The storage unit (54) is a non-volatile memory such as, for example, EEPROM (Electrically Erasable Programmable Read-Only Memory) or flash memory.

[0087] “Offset information” is information (e.g., voltage value) representing an offset voltage that is added to or subtracted from the composite signal (S24) in the offset processing described later. The offset information is measured or set in advance before shipment of the pump (1) under, for example, a predetermined reference driving condition (e.g., driving frequency: 60Hz, driving voltage: 200V) and stored in the storage unit (54).

[0088] “Offset processing” refers to a process of adding or subtracting an offset voltage to the composite signal (S24) so ​​that the difference value between the composite signal (S24) and the composite signal (S68) under reference driving conditions accurately represents the thrust direction displacement amount of the rotor (36) (thrust direction wear amount of the bearings (32, 33)). Through offset processing, the magnetic center position of the rotor (36) relative to the stator (37) in the thrust direction is virtually aligned with the mechanical center position of the rotor (36) relative to the stator (37) in the thrust direction (the two center positions coincide).

[0089] Whether the offset voltage is a signal added to the composite signal (S24) (addition signal) or a signal subtracted from it (subtraction signal) is determined by the magnitude of the composite signals (S24, S68). That is, for example, when the composite signal (S24) is greater than the composite signal (S68), the offset voltage is a subtraction signal, and conversely, when it is less, the offset information is an addition signal. In this embodiment, the offset voltage is an addition signal. This magnitude relationship is determined based on the signals for which offset processing has not been performed, namely the composite signals (S24, S68) input to the A / D converter (52) from the third path (L3) and the fourth path (L4).

[0090] “First correspondence relationship information” is information indicating the correspondence relationship between the thrust direction position (displacement amount) of the rotor (36) relative to the stator (37) under a predetermined driving condition and the difference value between the composite signal (S24) and the composite signal (S68). That is, the first correspondence relationship information indicates the correspondence relationship between the thrust direction wear amount of the bearings (32, 33) under a predetermined driving condition and the voltage value.

[0091] “Second correspondence relationship information” is information indicating the correspondence relationship between the radial direction position (displacement amount) of the rotor (36) relative to the stator (37) under a predetermined driving condition and the voltage value of the composite signal (S13, S57). That is, the second correspondence relationship information indicates the correspondence relationship between the radial direction wear amount of the bearings (32, 33) under a predetermined driving condition and the voltage value.

[0092] FIG. 9 is a schematic diagram showing an example of the appearance of the display part (55).

[0093] The display unit (55) displays the wear condition of the bearings (32, 33), the rotation direction of the rotation shaft (31), the detection coils (C1~C8), and the presence or absence of a break in the first path (L1) to the fourth path (L4). The display unit (55) is equipped with a plurality of LEDs (Light Emitting Diodes) that display, for example, the wear condition in the radial direction and thrust direction, the rotation direction, and the presence or absence of a break. The display unit (55) displays the wear condition in the radial direction and thrust direction in three stages: "green," "yellow," and "red," and displays the rotation direction as illuminated (forward rotation) and turned off (reverse rotation). Additionally, the display unit (55) displays the presence or absence of a break as illuminated (break present) and turned off (break not).

[0094] FIG. 10 is a functional block diagram of the offset processing unit (56).

[0095] The offset processing unit (56) performs offset processing based on offset information. The offset processing unit (56) includes a D / A converter (56a), an offset voltage generation circuit (56b), an operation circuit (56c), and a difference absolute value conversion circuit (56d).

[0096] The D / A converter (56a) converts offset information from a digital signal into an analog signal.

[0097] The offset voltage generation circuit (56b) generates an offset voltage that is added to or subtracted from the composite signal (S24) of the detection coils (C2, C4) based on offset information converted into an analog signal.

[0098] The operation circuit (56c) performs offset processing on the composite signal (S24) by adding or subtracting an offset voltage to the composite signal (S24), and calculates the difference between the composite signal (S24) and the composite signal (S68) after offset processing. The signal path (L13) is connected to the operation circuit (56c) via the signal path (L15) between the signal processing circuit (51c) and the A / D converter (52). The signal path (L14) is connected to the operation circuit (56c) via the signal path (L16) between the signal processing circuit (51d) and the A / D converter (52).

[0099] The difference absolute value conversion circuit (56d) converts the difference value calculated by the operation circuit (56c) into an absolute value. The signal representing this absolute value (hereinafter referred to as the "difference signal (Sd)") is converted into a digital signal by the A / D converter (52) and input to the control unit (53).

[0100] ● Setting of 1st to 4th thresholds

[0101] Next, the settings of the first to fourth thresholds are described below.

[0102] The “first threshold” is a threshold used to distinguish whether there is a disconnection in the detection coils (C1, C3) or the first path (L1). The first threshold is set based on the first maximum voltage value and the signal level of the noise component flowing through the detection coils (C1, C3) and the first path (L1). The first threshold is smaller than the third threshold and the fourth threshold.

[0103] The “second threshold” is a threshold used to distinguish whether there is a disconnection in the detection coil (C5, C7) or the second path (L2). The second threshold is set based on the second maximum voltage value and the signal level of the noise component flowing through the detection coil (C5, C7) and the second path (L2). The second threshold is smaller than the third threshold and the fourth threshold.

[0104] The “third threshold” is a threshold used to distinguish whether there is a disconnection in the detection coils (C2, C4) or the third path (L3). The third threshold is set based on the third maximum voltage value and the signal level of the noise component flowing through the detection coils (C2, C4) and the third path (L3).

[0105] The “fourth threshold” is a threshold used to distinguish whether there is a disconnection in the detection coils (C6, C8) or the fourth path (L4). The fourth threshold is set based on the fourth maximum voltage value and the signal level of the noise component flowing through the detection coils (C6, C8) and the fourth path (L4).

[0106] The first threshold and the second threshold are examples of radial thresholds in the present invention, and the third threshold and the fourth threshold are examples of thrust thresholds in the present invention. That is, the radial threshold includes the first threshold and the second threshold, and the thrust threshold includes the third threshold and the fourth threshold.

[0107] Generally, when a sensor fails, a receiving device that receives a signal from the sensor can detect the sensor failure by detecting an abnormal value of the signal. However, as described below, the device (5) detects the amount of wear in the thrust direction based on a difference signal (Sd) representing the difference value (absolute value) between the composite signal (S24) and the composite signal (S68). In this detection method, even if one signal path is disconnected, the other signal remains at a normal value. The amount of wear in the thrust direction is detected based on the voltage value of the fundamental component of the difference signal (Sd). Therefore, if one signal remains, the amount of wear in the thrust direction (of course, that amount of wear is different from the true amount of wear) can be detected similarly by the voltage value of the fundamental component of that signal. As a result, in a wire break detection method that simply uses only the voltage value of the difference signal (Sd), abnormal values ​​are not detected, and wire breakage of the detection coils (C2, C4, C6, C8), the third path (L3), and the fourth path (L4) may not be detected. Therefore, to detect wire breakage of the detection coils (C2, C4, C6, C8), the third path (L3), and the fourth path (L4), evaluating the voltage value of the composite signal (S24, S68) is more suitable than evaluating the voltage value of the difference signal (Sd).

[0108] Meanwhile, as described below, the device (5) detects the amount of wear in the radial direction based on the voltage value of the composite signal (S13, S57). In this detection method, for example, if the first path (L1) is disconnected, the composite signal (S13) is not included in the first signal (S1), and theoretically, the signal level becomes “0”. In this case, the device (5) can detect the disconnection of the detection coil (C1, C3) or the first path (L1) by recognizing that the value is an abnormal value. When detecting an abnormal value using a threshold value, the threshold value must be at least smaller than the voltage value of the composite signal (S13). Here, the amount of wear in the radial direction is detected based on the voltage value of each harmonic component of the composite signal (S13, S57). And the signal level (voltage value) of the harmonic component is small even in normal conditions (for example, tens of mV to about 300 mV), and may be equivalent to the signal level (voltage value) of the noise component. Therefore, even if a break occurs in the detection coil (C1, C3) or the first path (L1), the signal level of the first signal (S1) containing noise components does not become “0,” and the noise components may be mistaken for the composite signal (S13). As a result, in a break detection method that simply uses the voltage value of the composite signal (S13, S57), an abnormal value may be detected as a normal value. Therefore, in the detection method, it is difficult to detect breakage in the detection coil (C1, C3, C5, C7), the first path (L1), and the second path (L2). Thus, there is a technical challenge unique to the present device (5) in detecting breakage in the detection coil (C1, C3, C5, C7), the first path (L1), and the second path (L2). Therefore, in order to detect breakage in the detection coil (C1, C3, C5, C7), the first path (L1), and the second path (L2), threshold processing considering noise components is required.

[0109] In addition, the rotational speed (rotational speed) of the motor is generally changed by varying the driving frequency through inverter control. At this time, if only the driving frequency is lowered without lowering the driving voltage, the motor will be damaged; therefore, the driving frequency and the driving voltage are generally changed simultaneously. The increase and decrease in driving frequency and the increase and decrease in driving voltage are in a proportional relationship. As described above, since the fundamental component of the detection signal is generated by the driving voltage, the signal level (voltage value) of the fundamental component increases or decreases in proportion to the increase or decrease in the driving frequency and driving voltage. Furthermore, as the rotational speed of the motor increases or decreases, the frequency of the harmonic component and its signal level also increase or decrease. Moreover, as the bearings (32, 33) wear out, the voltage value of the composite signal (S13, S57) increases. Additionally, the contact resistance in the detection coils (C1~C8) and the first path (L1) to the fourth path (L4) increases over time, and the voltage value of each composite signal (S13, S57, S24, S68) increases accordingly. Therefore, the fixed value in the device (5) is not suitable as a threshold value for detecting a broken wire.

[0110] Accordingly, in the device (5), the first to fourth threshold values ​​are set by multiplying the first to fourth maximum voltage values ​​by a predetermined coefficient so that the first to fourth threshold values ​​change according to the latest trend of the voltage value. That is, the "coefficient" is a coefficient (%) that is multiplied by the first to fourth maximum voltage values ​​to set the first to fourth threshold values. Specifically, the first threshold value "V t1 " is the first maximum voltage value "V1 max It is the value obtained by multiplying "by the coefficient "A1", and the second threshold "V" t2 " is the second maximum voltage value "V2 max It is the value obtained by multiplying "by the coefficient "A2", and the third threshold "V" t3 "is the third maximum voltage value "V3 max It is the value obtained by multiplying "by the coefficient "A3", and the fourth threshold "V" t4 " is the 4th maximum voltage value "V4max It is the value obtained by multiplying the threshold value "A4". That is, the first threshold value to the fourth threshold value are variable values ​​that increase based on the voltage value (first maximum voltage value to fourth maximum voltage value) of each composite signal (S13, S57, S24, S68). Each coefficient is pre-set based on the signal level of the noise component expected by an operator, for example, at the time of shipment of the pump (1), and is included in this detection program and stored in the ROM (53c).

[0111] Each coefficient is set based on the signal level of the noise component included in the corresponding first signal (S1) to fourth signal (S4). Specifically, each coefficient is set such that the first threshold to fourth threshold is smaller than the voltage value of each composite signal (S13, S57, S24, S68) and also approximately exceeds the signal level of the noise component.

[0112] For example, when setting the first threshold value, as described above, the voltage value of the composite signal (S13) is small and may be equivalent to the voltage value of the noise component. Therefore, if the first threshold value is set high, even the normal value may be judged as an abnormal value (open circuit). Here, the voltage value of the noise component is not stable and fluctuates significantly. In addition, there are various types of noise components. Therefore, even if the first threshold value is set low, the frequency with which the voltage value of the noise component exceeds the first threshold value is low, and even if the voltage value of the noise component exceeds the first threshold value, there is a timing at which the voltage value becomes below the first threshold value. Also, the fluctuation range of the voltage value of the composite signal (S13) is relatively narrow (e.g., 0V to 300mV). Therefore, it is more difficult for false detection to occur if the first threshold value is set to a value that is significantly separated from the normal value. Accordingly, the coefficient used to set the first threshold value is set to a relatively small value (e.g., 30%). These settings are the same for the coefficients used to set the second threshold.

[0113] Meanwhile, for example, in the case of setting the third threshold, the voltage value of the composite signal (S24) is large (e.g., about 1V to 1.5V) and is sufficiently larger than the voltage value of the noise component. Therefore, the third threshold can be set to be larger than the voltage value of the noise component. Here, as described above, if the amount of wear in the thrust direction of the bearings (32, 33) increases, the voltage value of one of the composite signals (S24, S68) decreases. Therefore, the coefficient used to set the third threshold is set to a value (e.g., 50%) such that even if the bearings (32, 33) wear in the thrust direction, the normal value does not fall below the third threshold, and the third threshold becomes larger than the voltage value of the noise component. This setting is the same for the coefficient used to set the fourth threshold.

[0114] In this way, each coefficient is set based on the signal level (voltage value) of the noise component. In other words, the first to fourth thresholds are set based on the signal level (voltage value) of the noise component.

[0115] In addition, in the present invention, each coefficient is preferably greater than "0%" and less than or equal to "50%", and is not limited to the present embodiment.

[0116] ● Operation of the cand motor pump (motor bearing wear monitoring device (1))

[0117] Next, the operation of the pump (1) will be described below with a focus on the operation of the device (5). In the following description, FIGS. 1 to 10 will be appropriately referenced.

[0118] FIG. 11 is a flowchart showing an example of the operation of the device (5).

[0119] During the operation of the pump (1), driving power is supplied to the motor unit (3), and the rotor (36), rotating shaft (31), and impeller (21) rotate at a predetermined rotational speed. At this time, the device (5) continuously repeats the update process (ST1), the radial side disconnection detection process (ST2), the thrust side disconnection detection process (ST3), and the wear amount detection process (ST4). The radial side disconnection detection process (ST2) and the thrust side disconnection detection process (ST3) are examples of the detection method.

[0120] ● Update Processing

[0121] Figure 12 is a flowchart showing an example of update processing (ST1).

[0122] “Update processing (ST1)” is a process that periodically acquires the voltage values ​​of each composite signal (S13, S57, S24, S68) during the operation of the pump (1), and updates and stores the first to fourth maximum voltage values ​​stored in the RAM (53b). When the device (5) is started, update processing (ST1) is executed first. The detection coils (C1~C8) always output a detection signal while the rotor (36) is rotating.

[0123] First, the second acquisition unit (532) acquires a composite signal (S13) input to the A / D converter (52) from the first path (L1) as the first signal (S1), acquires a composite signal (S57) input to the A / D converter (52) from the second path (L2) as the second signal (S2), acquires a composite signal (S24) input to the A / D converter (52) from the third path (L3) as the third signal (S3), and acquires a composite signal (S68) input to the A / D converter (52) from the fourth path (L4) as the fourth signal (S4) to acquire the voltage values ​​"V1" ~ "V4" of each composite signal (S13, S57, S24, S68) (ST11: update acquisition step). The acquisition of each composite signal (S13, S57, S24, S68) is performed at a predetermined time interval (e.g., 10ms).

[0124] Next, the update unit (533) obtains the acquired voltage values ​​"V1" ~ "V4" and the first maximum voltage value "V1" stored in RAM (53b). max " ~ 4th maximum voltage value "V4 max " is compared (ST12: update comparison step). Specifically, the update unit (533) compares the voltage value "V1" of the composite signal (S13) with the first maximum voltage value "V1 max Compare " and the voltage value "V2" of the composite signal (S57) with the second maximum voltage value "V2" max Comparing ", the voltage value "V3" of the composite signal (S24) and the third maximum voltage value "V3 max Compare " and the voltage value "V4" of the composite signal (S68) with the fourth maximum voltage value "V4" max Compares "

[0125] The first maximum voltage value "V1" corresponding to any one of the voltage values ​​"V1" ~ "V4" of each composite signal (S13, S57, S24, S68). max " ~ 4th maximum voltage value "V4 max If it is greater than ("Y") of ST12, the update unit (533) updates the first maximum voltage value "V1" stored in RAM (53b). max " ~ 4th maximum voltage value "V4 max " Corresponding voltage value "V1 max " ~ "V4 max "Only the voltage values ​​"V1" ~ "V4" are updated (ST13: voltage value update step). That is, RAM (53b) updates the first maximum voltage value "V1" based on the determination result of the update unit (533). max " ~ 4th maximum voltage value "V4 max Update and save "

[0126] Next, the threshold setting unit (534) updates the first maximum voltage value "V1 max " ~ 4th maximum voltage value "V4 max A first threshold "V" corresponding to "based on" t1 " ~ 4th threshold "V t4Sets " (ST14: Threshold Update Step). Processing (ST14) sets the updated first maximum voltage value "V1 max " ~ 4th maximum voltage value "V4 max The first threshold "V corresponding to " t1 " ~ 4th threshold "V t4 Executed only for ". The corresponding first threshold "V t1 " ~ 4th threshold "V t4 After setting the configuration, the control unit (53) terminates the update processing (ST1).

[0127] Meanwhile, the first maximum voltage value "V1" corresponding to all voltage values ​​"V1" ~ "V4" of each composite signal (S13, S57, S24, S68) max " ~ 4th maximum voltage value "V4 max If it is less than or equal to ("N") of ST12, the update unit (533) updates the first maximum voltage value "V1" max " ~ 4th maximum voltage value "V4 max Without updating ", the control unit (53) terminates the update process (ST1).

[0128] Additionally, in the present invention, the processing (ST14) may be performed for all of the first to fourth threshold values.

[0129] In addition, in the present invention, when the device (5) is started, it is preferable that all of the first maximum voltage value to the fourth maximum voltage value are updated and all of the first threshold value to the fourth threshold value are set.

[0130] ● Radial side open circuit detection processing

[0131] FIG. 13 is a flowchart showing an example of a radial side open circuit detection process (ST2).

[0132] “Radial side open circuit detection process (ST2)” is a process for detecting whether there is an open circuit in the path of a signal (synthetic signal (S13, S57)) for detecting the amount of wear in the radial direction of the bearing (32, 33). That is, the radial side open circuit detection process (ST2) is a process for automatically detecting whether there is an open circuit in the detection coil (C1, C3, C5, C7) and the first path (L1) to the second path (L2).

[0133] First, the second acquisition unit (532) acquires the voltage value "V1" of the first signal (S1) input to the A / D converter (52) from the first path (L1), and acquires the voltage value "V2" of the second signal (S2) input to the A / D converter (52) from the second path (L2) (ST21: first acquisition step). The acquisition of the voltage values ​​"V1" and "V2" is performed at a predetermined time (e.g., 10ms). Here, if the detection coils (C1, C3, C5, C7) and the first path (L1) to the second path (L2) are not disconnected, the second acquisition unit (532) acquires a composite signal (S13) as the first signal (S1) and acquires a composite signal (S57) as the second signal (S2).

[0134] Additionally, in the present invention, the processing (ST21) may be substituted by the processing (ST11) in the update processing (ST1). That is, the second acquisition unit (532) may acquire the voltage values ​​"V1" and "V2" acquired in the processing (ST11).

[0135] Next, the disconnection detection unit (535) detects the voltage value "V1" of the acquired composite signal (S13) and the first threshold value "V t1 Compares (ST22: 1st comparison step).

[0136] The voltage value "V1" is the first threshold "V t1If it is less than "Y" of ST22, the open circuit detection unit (535) determines that there is an open circuit (more than) in the detection coils (C1, C3) and the first path (L1) (ST23). That is, the open circuit detection unit (535) detects an open circuit in the detection coils (C1, C3) and the first path (L1). At this time, the first signal (S1) does not include the composite signal (S13) and may include a noise component. In other words, the noise component may flow through the first path (L1) as the first signal (S1).

[0137] Meanwhile, the voltage value "V1" is the first threshold "V t1 In the case of an abnormality ("N" of ST22), the open circuit detection unit (535) determines that there is no open circuit in the detection coils (C1, C3) and the first path (L1) (normal) (ST24). At this time, the composite signal (S13) flows through the first path (L1) as the first signal (S1).

[0138] Next, the disconnection detection unit (535) detects the voltage value "V2" of the acquired composite signal (S57) and the second threshold value "V t2 Compares " (ST25: 2nd comparison step).

[0139] The voltage value "V2" is the second threshold "V t2 If it is less than "Y" of ST25, the open circuit detection unit (535) determines that there is an open circuit (more than) in the detection coil (C5, C7) and the second path (L2) (ST26). That is, the open circuit detection unit (535) detects an open circuit in the detection coil (C5, C7) and the second path (L2). At this time, the second signal (S2) does not include the composite signal (S57) and may include a noise component. In other words, the noise component may flow through the second path (L2) as the second signal (S2).

[0140] Meanwhile, the voltage value "V2" is the second threshold "V t2In the case of an abnormality ("N" of ST25), the open circuit detection unit (535) determines that there is no open circuit in the detection coils (C5, C7) and the second path (L2) (normal) (ST27). At this time, the composite signal (S57) flows through the second path (L2) as the second signal (S2).

[0141] Next, the display control unit (536) changes the display form of the display unit (55) based on the judgment result of the open circuit detection unit (535) (ST28: first display step). Specifically, if the open circuit detection unit (535) determines that it is "abnormal," the display control unit (536) turns on the radial side LED of the display unit (55). Meanwhile, if the open circuit detection unit (535) determines that it is "normal," the display control unit (536) turns off the radial side LED of the display unit (55). Next, the control unit (53) terminates the radial side open circuit detection process (ST2).

[0142] In this way, in the radial side open circuit detection process (ST2), a first threshold value is used to determine whether there is an open circuit in the detection coils (C1, C3) and the first path (L1). As previously mentioned, the first threshold value is not set to “0” but is set to a value corresponding to the noise component included in the first signal (S1). Therefore, when the detection coils (C1, C3) or the first path (L1) are open circuits, the open circuit detection unit (535) can detect the open circuit even if the first signal contains a noise component (even if the voltage value is not “0”). Here, due to the coefficient setting of the first threshold value, if the first signal (S1) contains a noise component having a signal level equivalent to that of the normal composite signal (S13), the open circuit detection unit (535) may fail to detect the open circuit and a false detection may occur. However, the voltage value of the noise component is unstable and fluctuates significantly. Therefore, although false detection may occur momentarily, when the voltage value of the noise component becomes below the first threshold value, the open circuit detection unit (535) can detect the open circuit of the detection coils (C1, C3) and the first path (L1). This effect is equally exerted in determining whether there is an open circuit in the detection coils (C5, C7) and the second path (L2).

[0143] In addition, in the radial-side open circuit detection process (ST2), the open circuit detection unit (535) automatically detects the open circuit by using a composite signal (S13, S57) used for detecting the amount of wear in the radial direction to automatically determine whether there is an open circuit in the detection coil (C1, C3, C5, C7) and the first path (L1) to the second path (L2). Therefore, the device (5) does not require dedicated wiring or circuits for the execution of the radial-side open circuit detection process (ST2). Furthermore, the device (5) does not require access from outside the device (5) to the terminals (terminal blocks) connected to the first path (L1) and the second path (L2). That is, the device (5) does not require access to the terminal blocks from outside the device (5) to check for the presence of an open circuit in the detection coil (C1, C3, C5, C7), etc. Therefore, the user of the pump (1) can safely check for disconnection of the detection coils (C1, C3, C5, C7) and the first path (L1) to the second path (L2) without stopping the pump (1).

[0144] In addition, in the present invention, the open circuit detection unit (535) may detect an open circuit of the detection coil (C1, C3) and the first path (L1) when the voltage value acquired during a predetermined time period falls below the first threshold value several times. This detection method is applied in the same way to the detection of open circuits of the detection coil (C5, C7) and the second path (L2).

[0145] ● Thrust side open circuit detection processing

[0146] FIG. 14 is a flowchart showing an example of thrust side open circuit detection processing (ST3).

[0147] “Thrust side open circuit detection process (ST3)” is a process for detecting whether there is an open circuit in the path of a signal (synthetic signal (S24, S68)) for detecting the amount of wear in the thrust direction of the bearing (32, 33). That is, the thrust side open circuit detection process (ST3) is a process for automatically detecting whether there is an open circuit in the detection coil (C2, C4, C6, C8) and the third path (L3) to the fourth path (L4).

[0148] First, the second acquisition unit (532) acquires the voltage value "V3" of the third signal (S3) input to the A / D converter (52) from the third path (L3), and acquires the voltage value "V4" of the fourth signal (S4) input to the A / D converter (52) from the fourth path (L4) (ST31: second acquisition step). The acquisition of the voltage values ​​"V3" and "V4" is performed at a predetermined time (e.g., 10ms). Here, if the detection coils (C2, C4, C6, C8) and the third path (L3) to the fourth path (L4) are not disconnected, the second acquisition unit (532) acquires the composite signal (S24) as the third signal (S3) and acquires the composite signal (S68) as the fourth signal (S4).

[0149] Additionally, in the present invention, the processing (ST31) may be substituted by the processing (ST11) in the update processing (ST1). That is, the second acquisition unit (532) may acquire the voltage values ​​"V3" and "V4" acquired in the processing (ST11).

[0150] Next, the disconnection detection unit (535) detects the voltage value "V3" of the acquired composite signal (S24) and the third threshold value "V t3 Compares (ST32: 3rd comparison step).

[0151] The voltage value "V3" is the third threshold "V t3If it is less than "Y" of ST32, the open circuit detection unit (535) determines that there is an open circuit (more than) in the detection coil (C2, C4) and the third path (L3) (ST33). That is, the open circuit detection unit (535) detects an open circuit in the detection coil (C2, C4) and the third path (L3). At this time, the third signal (S3) does not include the composite signal (S24) and may include a noise component. In other words, the noise component may flow through the third path (L3) as the third signal (S3).

[0152] Meanwhile, the voltage value "V3" is the third threshold "V t3 In the case of an abnormality ("N" of ST32), the open circuit detection unit (535) determines that there is no open circuit in the detection coils (C2, C4) and the third path (L3) (normal) (ST34). At this time, the composite signal (S24) flows through the third path (L3) as the third signal (S3).

[0153] Next, the disconnection detection unit (535) detects the voltage value "V4" of the acquired composite signal (S68) and the fourth threshold value "V t4 Compares " (ST35: 4th comparison step).

[0154] The voltage value "V4" is the fourth threshold "V t4 If it is less than "Y" of ST35, the open circuit detection unit (535) determines that there is an open circuit (more than) in the detection coils (C6, C8) and the fourth path (L4) (ST36). That is, the open circuit detection unit (535) detects an open circuit in the detection coils (C6, C8) and the fourth path (L4). At this time, the fourth signal (S4) does not include a composite signal (S68) and may include a noise component. In other words, the noise component may flow through the fourth path (L4) as the fourth signal (S4).

[0155] Meanwhile, the voltage value "V4" is the fourth threshold "V t4In the case of an abnormality ("N" of ST35), the open circuit detection unit (535) determines that there is no open circuit in the detection coils (C6, C8) and the fourth path (L4) (normal) (ST37). At this time, the composite signal (S68) flows through the fourth path (L4) as the fourth signal (S4).

[0156] Next, the display control unit (536) changes the display form of the display unit (55) based on the judgment result of the open circuit detection unit (535) (ST38: second display step). Specifically, if the open circuit detection unit (535) determines that it is "abnormal," the display control unit (536) turns on the thrust-side LED of the display unit (55). Meanwhile, if the open circuit detection unit (535) determines that it is "normal," the display control unit (536) turns off the thrust-side LED of the display unit (55). Next, the control unit (53) terminates the thrust-side open circuit detection process (ST3).

[0157] In this way, in the thrust side open circuit detection process (ST3), a third threshold value is used to determine whether there is an open circuit in the detection coils (C2, C4) and the third path (L3). As previously mentioned, the third threshold value is not set to “0” but is set to a value corresponding to the noise component included in the third signal. Therefore, when the detection coils (C2, C4) or the third path (L3) are open circuits, the open circuit detection unit (535) can reliably detect the open circuit even if the third signal contains a noise component (even if the voltage value is not “0”). This effect is equally exerted in determining whether there is an open circuit in the detection coils (C6, C8) and the fourth path (L4).

[0158] In addition, in the thrust-side open circuit detection process (ST3), the open circuit detection unit (535) automatically detects the open circuit by automatically determining whether there is an open circuit in the detection coils (C2, C4, C6, C8), the third path (L3), and the fourth path (L4) using the composite signal (S24, S68) used for determining the addition / subtraction of the offset voltage. That is, the open circuit detection unit (535) detects the open circuit using the composite signal (S24, S68) required for generating the difference signal (Sd) used to detect the amount of wear in the thrust direction. Therefore, the device (5) does not require dedicated wiring or circuits for the execution of the thrust-side open circuit detection process (ST3). In other words, the detection method can be executed simply by adding the detection program without changing the wiring and circuit configuration in a conventional motor bearing wear detection device. In addition, the device (5) does not require access from outside the device (5) to the terminals (terminal blocks) connected to the third path (L3) and the fourth path (L4). That is, the device (5) does not require access to the terminal blocks from outside the device (5) to check for open circuits in detection coils (C2, C4, C6, C8), etc. Therefore, the user of the pump (1) can safely check for open circuits in the detection coils (C2, C4, C6, C8) and the third path (L3) to the fourth path (L4) without stopping the pump (1).

[0159] ● Wear amount detection processing

[0160] FIG. 15 is a flowchart showing an example of a wear amount detection process (ST4).

[0161] “Wear amount detection processing (ST4)” is a process for detecting the amount of wear of bearings (32, 33) based on each composite signal (S13, S57, S24, S68). Wear amount detection processing (ST4) is an example of a wear amount detection method executed by the device (5).

[0162] The detection coils (C1~C8) always output a detection signal during the rotation of the rotor (36). The composite signal (S13, S57) from the detection coils (C1, C3, C5, C7) flows through the first path (L1) and the second path (L2) and is input to the A / D converter (52).

[0163] Detection signals (combined signals (S24, S68)) from detection coils (C2, C4, C6, C8) are input to an operation circuit (56c) through signal paths (L15) and (L16). Offset processing is performed in the operation circuit (56c), and a difference value is calculated. The difference value is converted into an absolute value by a difference absolute value conversion circuit (56d). The combined signal (S24), the combined signal (68), and the signal representing the absolute value (difference signal (Sd)) after offset are input to an A / D converter (52).

[0164] In the wear amount detection process (ST4), the wear amount detection unit (531) individually performs the radial direction wear amount detection process (ST41) and the thrust direction wear amount detection process (ST42). Since the radial direction wear amount detection process (ST41) and the thrust direction wear amount detection process (ST42) are known processes, only an overview is described below.

[0165] In the radial direction wear amount detection process (ST41), the first acquisition unit (530) acquires voltage values ​​"V1" and "V2" of the composite signal (S13, S57). Subsequently, the wear amount detection unit (531) detects the wear amount of the bearings (32, 33) based on the second corresponding relationship information and the voltage values ​​"V1" and "V2". Subsequently, the wear amount detection unit (531) compares the two wear amounts and selects the one with the larger wear amount as the radial direction wear amount. The detected wear amount is stored as log information, for example, in the storage unit (54).

[0166] In addition, in the present invention, the first acquisition unit (530) may acquire voltage values ​​"V1" and "V2" acquired in the processing (ST11).

[0167] In the thrust direction wear amount detection process (ST42), the first acquisition unit (530) acquires the voltage value (absolute value) "Vd" of the difference signal (Sd). The wear amount detection unit (531) detects the thrust direction wear amount of the bearings (32, 33) based on the first correspondence information and the voltage value "Vd". As described above, the difference signal (Sd) is generated from the composite signal (S24, S68). In other words, the wear amount detection unit (531) detects the thrust direction wear amount of the bearings (32, 33) based on the composite signal (S24, S68). The detected wear amount is stored as log information, for example, in the storage unit (54).

[0168] Next, the display control unit (536) determines the display form of the display unit (55) based on the detected amount of wear and displays the determined display form on the display unit (55) (ST43).

[0169] ●Summary (1)

[0170] According to the embodiment described above, the device (5) comprises a wear amount detection unit (531), a second acquisition unit (532), and a disconnection detection unit (535). The wear amount detection unit (531) detects the radial direction wear amount of the bearings (32, 33) based on the voltage values ​​of each of the composite signals (S13, S57), and detects the thrust direction wear amount of the bearings (32, 33) based on the voltage values ​​of each of the composite signals (S24, S68). The second acquisition unit (532) acquires a first signal (S1) flowing through a first path (L1), a second signal (S2) flowing through a second path (L2), a third signal (S3) flowing through a third path (L3), and a fourth signal (S4) flowing through a fourth path (L4). The open circuit detection unit (535) detects whether there is an open circuit in the detection coils (C1, C3) and the first path (L1) based on the voltage value of the first signal (S1) obtained through the first path (L1) and the first threshold value, detects whether there is an open circuit in the detection coils (C5, C7) and the second path (L2) based on the voltage value of the second signal (S2) obtained through the second path (L2) and the second threshold value, detects whether there is an open circuit in the detection coils (C2, C4) and the third path (L3) based on the voltage value of the third signal (S3) obtained through the third path (L3) and the third threshold value, and detects whether there is an open circuit in the detection coils (C6, C8) and the fourth path (L4) based on the voltage value of the fourth signal (S4) obtained through the fourth path (L4) and the fourth threshold value. When the wire breakage detection unit (535) does not detect a wire breakage, the composite signal (S13) flows through the first path (L1) as the first signal (S1), the composite signal (S57) flows through the second path (L2) as the second signal (S2), the composite signal (S24) flows through the third path (L3) as the third signal (S3), and the composite signal (S68) flows through the fourth path (L4) as the fourth signal (S4).The first threshold is set to be smaller than the voltage value of the composite signal (S13), the second threshold is set to be smaller than the voltage value of the composite signal (S57), the third threshold is set to be smaller than the voltage value of the composite signal (S24), and the fourth threshold is set to be smaller than the voltage value of the composite signal (S68). According to this configuration, the device (5) does not require dedicated wiring or circuits for the execution of the detection method. In addition, the device (5) can automatically detect whether there is a disconnection in the detection coils (C1~C8) and the first path (L1) ~ fourth path (L4). Therefore, the user of the pump (1) can safely check whether there is a disconnection in the detection coils (C1~C8) and the first path (L1) ~ fourth path (L4) without stopping the pump (1).

[0171] Additionally, according to the embodiment described above, the RAM (53b) updates and stores the first maximum voltage value to the fourth maximum voltage value. The first threshold is set based on the first maximum voltage value, the second threshold is set based on the second maximum voltage value, the third threshold is set based on the third maximum voltage value, and the fourth threshold is set based on the fourth maximum voltage value. According to this configuration, the first threshold to the fourth threshold are set to change according to the latest trend of the voltage value. Accordingly, the device (5) can appropriately detect whether there is a disconnection even if the voltage value of each composite signal (S13, S57, S24, S68) increases over time, and can appropriately detect whether there is a disconnection even if the driving frequency increases.

[0172] In addition, according to the embodiment described above, the first threshold is set based on the signal level of the noise component included in the first signal (S1), the second threshold is set based on the signal level of the noise component included in the second signal (S2), the third threshold is set based on the signal level of the noise component included in the third signal (S3), and the fourth threshold is set based on the signal level of the noise component included in the fourth signal (S4). According to this configuration, even if the first signal (S1) to the fourth signal (S4) contain a noise component, the device (5) can automatically detect whether there is a disconnection in the detection coils (C1~C8) and the first path (L1) to the fourth path (L4).

[0173] In addition, according to the embodiment described above, the first threshold and the second threshold are smaller than the third threshold and the fourth threshold. According to this configuration, the first to fourth thresholds can be set to values ​​corresponding to the signal levels of each composite signal (S13, S57, S24, S68). As a result, the open circuit detection unit (535) can reliably detect whether there is an open circuit in the detection coils (C2, C4, C6, C8) and the third path (L3) to the fourth path (L4) without being particularly affected by noise components.

[0174] In addition, according to the embodiment described above, the device (5) is provided with a threshold setting unit (534) for setting a first threshold to a fourth threshold. According to this configuration, the device (5) can automatically set the first threshold to a fourth threshold according to the latest trends in the signal level and voltage value of the noise component.

[0175] In addition, in the embodiment described above, the detection method is executed by the control unit (53). Alternatively, the detection method may be executed by an external computing device (e.g., a computer) connected to the device (5).

[0176] In addition, in the embodiment described above, some or all of the information stored in the RAM (53b) (e.g., first maximum voltage value to fourth maximum voltage value, first threshold value to fourth threshold value, etc.) may be stored in the storage unit (54).

[0177] In addition, in the embodiment described above, the device (5) may have a function to acquire a signal level of a noise component from the voltage values ​​of each of the first signal (S1) to the fourth signal (S4), and to set a coefficient based on the acquired signal level of the noise component. Acquisition of the signal level of the noise component is performed, for example, using known filter processing and FFT.

[0178] In addition, in the embodiment described above, the device (5) may detect whether there is a disconnection in the detection coils (C2, C4, C6, C8), the third path (L3) to the fourth path (L4), and the signal paths (L15, L16) based on the difference signal (Sd) and the threshold value (fifth threshold value) corresponding to the difference signal (Sd). As described above, the difference signal (Sd) can be a normal value if a composite signal of one side exists. However, since the voltage value of one side for calculating the difference value is extremely low, the voltage value (absolute value) of the difference signal (Sd) in the event of an abnormality becomes greater than the corresponding voltage value in the event of normality. Therefore, unlike the first threshold value to the fourth threshold value, the fifth threshold value is set to be greater than the voltage value of the difference signal (Sd), so that the device (5) can detect whether there is a disconnection based on the voltage value of the difference signal (Sd) and the fifth threshold value. In this case, the device (5) also stores the maximum value of the voltage value of the differential signal (Sd) as the fifth maximum voltage value in the storage unit (54). Here, the voltage value during an abnormal condition may deviate significantly from the latest trend of the voltage value during normal conditions. Therefore, the device (5) may periodically acquire the amount of change in the voltage value of the differential signal (Sd) and, based on the amount of change, detect whether there is a disconnection in the detection coil (C2, C4, C6, C8), the third path (L3) ~ the fourth path (L4), and the signal path (L15, L16).

[0179] In addition, in the embodiment described above, the device (5) does not need to be equipped with a threshold setting unit (534). In this case, the first to fourth threshold values ​​are fixed values, so the accuracy of wire breakage detection is reduced.

[0180] In addition, in the embodiments described above, the first to fourth threshold values ​​may be set to be smaller than the voltage value of at least the corresponding composite signal (S13, S57, S24, S68), and may not necessarily be set based on the maximum voltage value or noise component.

[0181] In addition, in the above-described embodiment, the detection program and each coefficient may be stored in the storage unit (54).

[0182] ●Motor bearing wear monitoring device (2)●

[0183] Next, another embodiment of the device (hereinafter referred to as the "Second Embodiment") will be described below, focusing on the parts that differ from the previously described embodiment (hereinafter referred to as the "First Embodiment"). The Second Embodiment differs from the First Embodiment in that it estimates the presence or absence of a disconnection using a learning model. In the following description, elements common to the First Embodiment are assigned the same reference numerals, and their descriptions are omitted.

[0184] ● Configuration of the motor bearing wear monitoring device (2)

[0185] FIG. 16 is a functional block diagram showing another embodiment (second embodiment) of the present device.

[0186] The device (5A) comprises eight detection coils (C1 to C8), a connection unit (50), two common paths (Lc1, Lo2), six signal paths (L11 to L16), four signal processing circuits (51a to 51d), an A / D converter (52), a control unit (53A), a storage unit (54A), a display unit (55), and an offset processing unit (56). The A / D converter (52) and the control unit (53A) are configured, for example, by a microcomputer.

[0187] The configuration of the device (5A) is common to the configuration of the device (5) of the first embodiment, except for the control unit (53A) and the storage unit (54A). Additionally, in the device (5A), the estimation program of the first embodiment estimates the presence or absence of a broken wire using a learning model described later. That is, the device (5A) executes a method for estimating a broken wire of the detection coils (C1~C8) using a learning model instead of the detection method (hereinafter simply referred to as the "estimation method"). Details of the learning model will be described later.

[0188] The control unit (53A) controls the operation of the entire device (5A). The control unit (53A) is composed of a processor, such as a CPU (53a), volatile memory, such as RAM (53b), which functions as a work area of ​​the CPU (53a), and non-volatile memory, such as ROM (53c), which stores various information, such as the estimation program or other control programs (e.g., a wear amount detection program). The control unit (53A) is equipped with a first acquisition unit (530), a wear amount detection unit (531), a second acquisition unit (532), an update unit (533), a display control unit (536), and a disconnection estimation unit (537).

[0189] In the control unit (53A), the estimation program is operated, and the estimation program cooperates with the hardware resources of the device (5A) to realize the estimation method described below. Additionally, when the estimation program is executed on the processor (CPU (53a)) constituting the control unit (53A), the estimation program can cause the processor to function as a second acquisition unit (532), a display control unit (536), and a disconnection estimation unit (537), thereby enabling the estimation method to be executed on the processor. Furthermore, when the computer is made to execute the estimation program and the wear amount detection program, the estimation program and the wear amount detection program can cause the computer to function as the device (5A).

[0190] In addition, the estimation program in the present invention may be stored in a storage unit (54A). In addition, the estimation program may be stored in an installable file format or an executable file format on a non-transient storage medium (e.g., CD, DVD, USB memory, etc.) and provided to the device (5A) through a dedicated reading medium.

[0191] The open circuit estimation unit (537) estimates whether there is an open circuit in the detection coils (C1~C8) and the first path (L1) ~ fourth path (L4) based on the first signal (S1) ~ fourth signal (S4), the first maximum voltage value ~ fourth maximum voltage value and the learning models described later (first learning model (M1), second learning model (M2), third learning model (M3), and fourth learning model (M4)). The specific operation of the open circuit estimation unit (537) will be described later.

[0192] The storage unit (54A) stores information necessary for the operation of the device (5A) (e.g., first learning model (M1) to fourth learning model (M4), offset information, first correspondence relationship information, second correspondence relationship information, etc.). The storage unit (54A) is a non-volatile memory, such as an EEPROM or flash memory. The storage unit (54A) is an example of a learning model storage unit in the present invention.

[0193] FIG. 17 is a schematic diagram showing an example of information (first learning model (M1) to fourth learning model (M4)) stored in a storage unit (54A).

[0194] The “first learning model (M1)” is the voltage value “V1” of the first signal (S1) and the first maximum voltage value “V1 max It is a machine learning algorithm (i.e., a learning model) that has been machine learned to output whether there is a disconnection (normal / abnormal) of the detection coils (C1, C3) and the first path (L1) when input is received. The first learning model (M1) is, for example, generated in advance by a machine learning device and stored in a storage unit (54A).

[0195] The “second learning model (M2)” is the voltage value “V2” of the second signal (S2) and the second maximum voltage value “V2 max It is a machine-learned completed learning model that outputs whether there is a disconnection (normal / abnormal) of the detection coils (C5, C7) and the second path (L2) when input is received. The second learning model (M2) is, for example, generated in advance by a machine learning device and stored in a storage unit (54A).

[0196] The “third learning model (M3)” is the voltage value “V3” of the third signal (S3) and the third maximum voltage value “V3 max It is a machine-learned completed learning model that outputs whether there is a disconnection (normal / abnormal) of the detection coils (C2, C4) and the third path (L3) when input is received. The third learning model (M3) is, for example, generated in advance by a machine learning device and stored in a storage unit (54A).

[0197] The “fourth learning model (M4)” is the voltage value “V4” of the fourth signal (S4) and the fourth maximum voltage value “V4” max It is a machine-learned completed learning model that outputs whether there is a disconnection (normal / abnormal) of the detection coils (C6, C8) and the fourth path (L4) when input is received. The fourth learning model (M4) is, for example, generated in advance by a machine learning device and stored in a storage unit (54A).

[0198] The first learning model (M1) and the second learning model (M2) are examples of a radial learning model in the present invention, and the third learning model (M3) and the fourth learning model (M4) are examples of a thrust learning model in the present invention. That is, the radial learning model includes the first learning model (M1) and the second learning model (M2), and the thrust learning model includes the third learning model (M3) and the fourth learning model (M4).

[0199] Here, machine learning by a machine learning device is performed by machine learning training data using, for example, a known machine learning algorithm (e.g., a neural network having an input layer, a plurality of intermediate layers, and an output layer). "Training data" includes information that serves as input data for a machine learning algorithm (learning model) and information that serves as output data (teacher data) related to the input data.

[0200] “Input data” is an explanatory variable in machine learning, and in this embodiment, it is the voltage value of the first signal (S1) to the fourth signal (S4) and the first maximum voltage value to the fourth maximum voltage value in a predetermined state (predetermined driving condition, predetermined wear state, predetermined period, presence or absence of disconnection). As described above, if the detection coil (C1, C3) and the first path (L1) are not disconnected, the composite signal (S13) flows as the first signal (S1), and its voltage value is a normal value greater than the first threshold value. On the other hand, if the detection coil (C1, C3) or the first path (L1) is disconnected, the composite signal (S13) is not included in the first signal (S1), and its voltage value is an abnormal value smaller than the first threshold value. Likewise, if the detection coils (C2, C4 ~ C8) and the second path (L2) ~ fourth path (L4) are not disconnected, the voltage values ​​of the second signal (S2) ~ fourth signal (S4) are normal values ​​greater than the corresponding second threshold ~ fourth threshold. On the other hand, if the detection coils (C2, C4 ~ C8) or the second path (L2) ~ fourth path (L4) are disconnected, the voltage values ​​of the second signal (S2) ~ fourth signal (S4) are abnormal values ​​smaller than the corresponding second threshold ~ fourth threshold. Furthermore, in the first embodiment, the first threshold ~ fourth thresholds used to determine the presence or absence of disconnection are set as a ratio to the first maximum voltage value ~ fourth maximum voltage value. Therefore, the first threshold ~ fourth thresholds are proportional to the first maximum voltage value ~ fourth maximum voltage value. Therefore, there is a correlation between the voltage value of the first signal (S1) and the first maximum voltage value, and the presence or absence of a disconnection in the detection coil (C1, C3) and the first path (L1). Similarly, there is a correlation between the voltage values ​​of the second signal (S2) to the fourth signal (S4) and the second maximum voltage value to the fourth maximum voltage value, and the presence or absence of a disconnection in the detection coil (C5, C7, C2, C4, C6, C8) and the second path (L2) to the fourth path (L4). In this way, there is a correlation between the input data and the output data.Input data is obtained by operating a test device, for example, that mimics a pump (1), under predetermined conditions for a predetermined time. Here, the presence or absence of a disconnection can be reproduced by turning on / off switches installed in various places in the test device (for example, between detection coils (C1, C3) connected in series, between detection coil (C3) and the connection part (50), etc.).

[0201] In addition, the input data may be similar signals (voltage values) generated within a predetermined period by a signal generating device based on actual data (e.g., log data) acquired in the past from a pump of the same model as, for example, pump (1).

[0202] Here, "predetermined driving conditions" is a driving frequency according to the environment in which the pump (1) is installed, among driving frequencies between 40Hz and 60Hz, for example. "Predetermined wear conditions" is a wear condition in which each composite signal (S13, S57, S24, S68) becomes a normal value, for example. "Predetermined periods" is the time (for example, several seconds to tens of seconds) during which a signal usable as learning data is obtained under predetermined driving conditions and predetermined wear conditions.

[0203] “Output data” is an objective variable in machine learning, and in this embodiment, it is information indicating the “presence” or “absence” of a disconnection in the detection coils (C1~C8) and the first path (L1) to the fourth path (L4). For example, numerical values ​​such as “0” and “1” are assigned to the “presence” or “absence” of the disconnection. One output data is related to one input data and constitutes one training data.

[0204] Furthermore, in the present invention, the output data is not limited to the two states of "present" or "absence" of a disconnection. That is, for example, if there is a difference in the signal level of the noise component depending on the location of the disconnection, the output data may include the "location of the disconnection."

[0205] In addition, the machine learning algorithm used in the machine learning of the present invention is not limited to a neural network, provided that the first learning model (M1) to the fourth learning model (M4), generated by machine learning using a plurality of learning data, can estimate whether there is a disconnection. That is, for example, the machine learning algorithm may be a random forest, a decision tree, a support vector machine, etc.

[0206] The first learning model (M1) generated in this way can output "presence" or "absence" of a disconnection in the detection coil (C1, C3) or the first path (L1) by inputting the voltage value of the first signal (S1) and the first maximum voltage value, as shown in FIG. 17. That is, the first learning model (M1) is machine-learned to output "presence" or "absence" of a disconnection in the detection coil (C1, C3) or the first path (L1) when the voltage value of the first signal (S1) and the first maximum voltage value are input as input data. Likewise, the second learning model (M2) to the fourth learning model (M4) are machine-learned to output the "presence" or "absence" of a disconnection in the corresponding detection coil (C2, C4 to C8) or the second path (L2) to the fourth path (L4) when the voltage values ​​of the corresponding second signal (S2) to the fourth signal (S4) and the second maximum voltage value to the fourth maximum voltage value are input as input data.

[0207] ● Operation of the cand motor pump (motor bearing wear monitoring device (2))

[0208] Next, the operation of the pump (1) (i.e., the estimation method) will be explained below with a focus on the operation of the device (5A).

[0209] FIG. 18 is a flowchart showing an example of the operation of the device (5A).

[0210] In the second embodiment, the operation of the pump (1) is common to the operation of the pump (1) in the first embodiment, except that the device (5A) performs a radial-side open circuit estimation process (ST5) and a thrust-side open circuit estimation process (ST6) instead of a radial-side open circuit detection process (ST2) and a thrust-side open circuit detection process (ST3). That is, the device (5A) constantly repeats the update process (ST1), the radial-side open circuit estimation process (ST5), the thrust-side open circuit estimation process (ST6), and the wear amount detection process (ST4). The radial-side open circuit estimation process (ST5) and the thrust-side open circuit estimation process (ST6) are examples of estimation methods. Fig. 16 is appropriately referenced in the following description.

[0211] ● Estimation of radial side open circuit processing

[0212] FIG. 19 is a flowchart showing an example of radial side single-line estimation processing (ST5).

[0213] “Radial side open circuit estimation process (ST5)” is a process for estimating whether there is an open circuit in the path of a signal (synthetic signal (S13, S57)) for detecting the amount of wear in the radial direction of the bearing (32, 33). That is, the radial side open circuit estimation process (ST5) is a process for automatically estimating whether there is an open circuit in the detection coil (C1, C3, C5, C7) and the first path (L1) to the second path (L2).

[0214] First, the second acquisition unit (532) acquires the voltage value "V1" of the first signal (S1) input to the A / D converter (52) from the first path (L1), and acquires the voltage value "V2" of the second signal (S2) input to the A / D converter (52) from the second path (L2), and at the same time acquires the first maximum voltage value "V1" from the RAM (53b). max " and second maximum voltage value "V2 max "Acquires (ST51: 1st acquisition step). Acquiring each voltage value is performed at a predetermined time (e.g., 10ms).

[0215] Next, the single-line estimation unit (537) has a voltage value "V1" and a first maximum voltage value "V1" max " is input into the first learning model (M1), and based on the output of the first learning model (M1), the "presence" or "absence" of a break in the detection coils (C1, C3) and the first path (L1) is estimated. Likewise, the break estimation unit (537) estimates the voltage value "V2" and the second maximum voltage value "V2" max " is input into the second learning model (M2), and based on the output of the second learning model (M2), the presence or absence of a break in the detection coil (C5, C7) and the second path (L2) is estimated (ST52: first estimation step).

[0216] Next, the display control unit (536) determines the display form of the display unit (55) based on whether the estimated disconnection is "present" or "absent" and displays the determined display form on the display unit (55) (ST53: first display step). That is, for example, if the disconnection is estimated to be "present," the display control unit (536) lights up the radial side LED of the display unit (55). Subsequently, the control unit (53A) terminates the radial side disconnection estimation process (ST5).

[0217] ● Thrust-side single-line presumed processing

[0218] FIG. 20 is a flowchart showing an example of thrust-side single-line estimation processing (ST6).

[0219] “Thrust-side open circuit estimation process (ST6)” is a process for estimating whether there is an open circuit in the path of a signal (synthetic signal (S24, S68)) for detecting the amount of wear in the thrust direction of the bearing (32, 33). That is, the thrust-side open circuit estimation process (ST6) is a process for automatically estimating whether there is an open circuit in the detection coil (C2, C4, C6, C8) and the third path (L3) to the fourth path (L4).

[0220] First, the second acquisition unit (532) acquires the voltage value "V3" of the third signal (S3) input to the A / D converter (52) from the third path (L3), and acquires the voltage value "V4" of the fourth signal (S4) input to the A / D converter (52) from the fourth path (L4), and at the same time acquires the third maximum voltage value "V3" from the RAM (53b). max " and 4th maximum voltage value "V4 max " is acquired (ST61: second acquisition step). Acquisition of each voltage value is performed at predetermined times (e.g., 10ms).

[0221] Next, the single-line estimation unit (537) has a voltage value "V3" and a third maximum voltage value "V3" max " is input into the third learning model (M3), and based on the output of the third learning model (M3), the "presence" or "absence" of a break in the detection coils (C2, C4) and the third path (L3) is estimated. Likewise, the break estimation unit (537) estimates the voltage value "V4" and the fourth maximum voltage value "V4 max " is input into the fourth learning model (M4), and based on the output of the fourth learning model (M4), the "presence" or "absence" of the disconnection of the detection coils (C6, C8) and the fourth path (L4) is estimated (ST62: second estimation step).

[0222] Next, the display control unit (536) determines the display form of the display unit (55) based on whether the estimated disconnection is "present" or "absent" and displays the determined display form on the display unit (55) (ST63: second display step). That is, for example, if the disconnection is estimated to be "present," the display control unit (536) lights up the thrust-side LED of the display unit (55). Subsequently, the control unit (53A) terminates the thrust-side disconnection estimation process (ST6).

[0223] ●Summary (2)

[0224] According to the above-described embodiment, the device (5A) comprises a RAM (53b), a wear amount detection unit (531), a second acquisition unit (532), a disconnection estimation unit (537), and a storage unit (54A). The RAM (53b) updates and stores the first maximum voltage value to the fourth maximum voltage value. The second acquisition unit (532) acquires the voltage values ​​of the first maximum voltage value to the fourth maximum voltage value and the first signal (S1) to the fourth signal (S4). The storage unit (54A) stores the first learning model (M1) to the fourth learning model (M4). The open circuit estimation unit (537) inputs the voltage values ​​of each of the first signal (S1) to the fourth signal (S4) and the first maximum voltage value to the fourth maximum voltage value, respectively, into the corresponding first learning model (M1) to the fourth learning model (M4) to estimate whether there is an open circuit in the detection coils (C1~C8) or the first path (L1) to the fourth path (L4). According to this configuration, the device (5A) does not require dedicated wiring or circuits for the execution of the estimation method. Furthermore, the device (5A) can automatically estimate whether there is an open circuit in the detection coils (C1~C8) and the first path (L1) to the fourth path (L4) without undergoing threshold processing like the device (5) of the first embodiment. Therefore, the user of the pump (1) can safely check whether there is an open circuit in the detection coils (C1~C8) and the first path (L1) to the fourth path (L4) without stopping the pump (1).

[0225] ●Other embodiments●

[0226] In each of the embodiments described above, if the present invention is implementable, the number of detection coils (C1 to C8) is not limited to "8".

[0227] In addition, in each of the embodiments described above, the control unit (53, 53A) may be composed of a processor such as a DSP (Digital Signal Processor) or a (GP)GPU ((General Purpose) Graphics Processing Unit) instead of a CPU (53a).

[0228] Furthermore, in the second embodiment described above, the estimation method was executed by the control unit (53A). Alternatively, the estimation method may be executed by an external computing device (e.g., a computer) connected to the device (5A).

[0229] In addition, in the second embodiment described above, some of the information stored in the storage unit (54A) (e.g., the first learning model (M1) to the fourth learning model (M4)) may be included in the estimation program and stored in the ROM (53c). In this case, the ROM (53c) can function as a learning model storage unit in the present invention.

[0230] In addition, in each of the embodiments described above, the pump (1) may not be equipped with the device (5, 5A). That is, for example, the detection coils (C1~C8) may be provided in the motor unit (3), and the device (5, 5A) may be disposed separately from the pump unit (2), the motor unit (3), and the adapter (4). In this case, the device (5, 5A) may be connected to the detection coils (C1~C8) via a cable, or the device (5, 5A) and the motor unit (3) may be configured to have a communication function so that the device (5, 5A) is connected to the motor unit (3) via a wireless communication line to receive a detection signal.

[0231] In addition, in the second embodiment described above, the estimation program may be stored in the storage unit (54A).

[0232] In addition, in each of the above-described embodiments, the pump (1) may be equipped with detection coils (C1~C8) instead of the device (5, 5A).

[0233] ● Embodiments of the present invention ●

[0234] Next, embodiments of the present invention identified from each of the embodiments described above are described below by reference to the terms and symbols used in each embodiment.

[0235] A first embodiment of the present invention is a motor bearing wear monitoring device (e.g., motor bearing wear monitoring device (5)) that monitors the wear condition of a bearing (e.g., bearing (32, 33)) supporting a rotation axis (e.g., rotation axis (31)) of a rotor (e.g., rotor (36)) based on a detection signal of each of a plurality of detection coils (e.g., detection coils C1 to C8) that detect a change in magnetic flux corresponding to a change in the mechanical position of a rotor (e.g., rotation axis (31)) of a motor (e.g., motor part (3)) of a canned motor pump (e.g., canned motor pump (1)). The plurality of detection coils includes a group of radial detection coils (e.g., detection coils C1, C3, detection coils C5, C7)) that detect the change in magnetic flux in the radial direction of the rotation axis, and a group of thrust detection coils (e.g., detection coils C2, C4, detection coils C6, C8)) that detect the change in magnetic flux in the thrust direction of the rotation axis. In the thrust direction above, the radial detection coil and the thrust detection coil are disposed at one-way or other-way end of the stator, and the radial detection coil is electrically connected to a radial signal path (e.g., first path (L1), second path (L2)) through which a radial composite signal (e.g., composite signal (S13), composite signal (S57)) formed by synthesizing the detection signals of each of the radial detection coils flows, and the thrust detection coil is electrically connected to a thrust signal path (e.g., third path (L3), fourth path (L4)) through which a thrust composite signal (e.g., composite signal (S24), composite signal (S68)) formed by synthesizing the detection signals of each of the thrust detection coils flows, and a radial threshold value (e.g., first threshold value, second threshold value) set to be smaller than the voltage value of the radial composite signal and a thrust threshold value (e.g., third threshold value) set to be smaller than the voltage value of the thrust composite signalThe apparatus comprises a threshold storage unit (e.g., RAM (53b)) for storing a fourth threshold value, an acquisition unit (e.g., second acquisition unit (532)) for acquiring a radial path signal (e.g., first signal (S1), second signal (S2)) flowing through the radial signal path and a thrust path signal (e.g., third signal (S3), fourth signal (S4)) flowing through the thrust signal path, and a disconnection detection unit (e.g., disconnection detection unit (535)) for detecting whether the detection coil, the radial signal path, and the thrust signal path are disconnected, and when the detection coil, the radial signal path, and the thrust signal path are not disconnected, the radial composite signal flows through the radial signal path as the radial path signal, and the thrust composite signal flows through the thrust signal path as the thrust path signal, and the disconnection detection unit detects the voltage value of the radial path signal and the radial threshold value A motor bearing wear monitoring device that detects whether there is a disconnection between a radial detection coil and a radial signal path, and detects whether there is a disconnection between the thrust detection coil and the thrust signal path based on the voltage value of the thrust path signal and the thrust threshold value.

[0236] According to this configuration, the pump user can safely check for open circuits in the detection coil and paths 1 through 4 without stopping the pump.

[0237] A second embodiment of the present invention is a motor bearing wear monitoring device having, in the first embodiment, a voltage value storage unit (e.g., RAM (53b)) that updates and stores a radial maximum voltage value which is the maximum value among the voltage values ​​of the radial composite signal and a thrust maximum voltage value which is the maximum value among the voltage values ​​of the thrust composite signal, wherein the radial threshold value is set based on the radial maximum voltage value and the thrust threshold value is set based on the thrust maximum voltage value.

[0238] According to this configuration, the device can properly detect whether there is a disconnection even if the voltage value of each composite signal increases over time.

[0239] A third embodiment of the present invention is a motor bearing wear monitoring device, wherein, in the second embodiment, the radial threshold is set based on the signal level of a noise component included in the radial path signal, and the thrust threshold is set based on the signal level of a noise component included in the thrust path signal.

[0240] According to this configuration, even if noise components are included in the first to fourth signals, the device can automatically detect whether the detection coil and the first to fourth paths are disconnected.

[0241] The fourth embodiment of the present invention is a motor bearing wear monitoring device in which, in the third embodiment, the radial threshold is smaller than the thrust threshold.

[0242] According to this configuration, the first to fourth thresholds can be set to values ​​based on the signal level of the composite signal.

[0243] A fifth embodiment of the present invention is a motor bearing wear monitoring device having a threshold setting unit (e.g., a threshold setting unit (534)) for setting each of the radial threshold and the thrust threshold in any one of the first to fourth embodiments.

[0244] According to this configuration, the device can automatically set a first threshold to a fourth threshold based on the latest trends in the signal level and voltage value of the noise component.

[0245] A sixth embodiment of the present invention is a first embodiment wherein the plurality of detection coils includes a group of first radial detection coils (e.g., detection coils (C1, C3)) and a group of second radial detection coils (e.g., detection coils (C5, C7)) functioning as a group of radial detection coils, a group of first thrust detection coils (e.g., detection coils (C2, C4)) and a group of second thrust detection coils (e.g., detection coils (C6, C8)) functioning as a group of thrust detection coils, wherein the first radial detection coils and the first thrust detection coils are disposed at the one-way end of the stator, and the second radial detection coils and the second thrust detection coils are disposed at the other-way end of the stator, and the radial signal path is electrically connected to the first radial detection coils and a first composite signal (e.g., composite) formed by synthesizing the detection signals of each of the first radial detection coils. The thrust signal path comprises a first path (e.g., first path (L1)) through which a signal (S13) flows as the radial composite signal, and a second path (e.g., second path (L2)) through which a second composite signal (e.g., composite signal (S57)) formed by synthesizing the detection signals of each of the second radial detection coils is electrically connected to the second radial detection coil and flows as the radial composite signal, and the thrust signal path comprises a third path (e.g., third path (L3)) through which a third composite signal (e.g., composite signal (S24)) formed by synthesizing the detection signals of each of the first thrust detection coils is electrically connected to the first thrust detection coil and flows as the thrust composite signal, and a fourth path (e.g., fourth path (L4)) through which a fourth composite signal (e.g., composite signal (S68)) formed by synthesizing the detection signals of each of the second thrust detection coils is electrically connected to the second thrust detection coil and flows as the thrust composite signal. Equipped,The above radial threshold includes a first threshold set to be smaller than the voltage value of the first composite signal and a second threshold set to be smaller than the voltage value of the second composite signal, and the above thrust threshold includes a third threshold set to be smaller than the voltage value of the third composite signal and a fourth threshold set to be smaller than the voltage value of the fourth composite signal, and the acquisition unit acquires each of the first signal flowing through the first path (e.g., first signal (S1)) and the second signal flowing through the second path (e.g., second signal (S2)) as the radial path signal, and acquires each of the third signal flowing through the third path (e.g., third signal (S3)) and the fourth signal flowing through the fourth path (e.g., fourth signal (S4)) as the thrust path signal, and when the detection coil, the first path, the second path, the third path, and the fourth path are not disconnected, the first composite signal flows through the first path as the first signal, and the second composite signal flows through the second A motor bearing wear monitoring device, wherein the signal flows through the second path as a signal, the third composite signal flows through the third path as a third signal, the fourth composite signal flows through the fourth path as a fourth signal, and the open circuit detection unit detects the presence or absence of open circuit between the first radial detection coil and the first path based on the voltage value of the first signal and the first threshold value, detects the presence or absence of open circuit between the second radial detection coil and the second path based on the voltage value of the second signal and the second threshold value, detects the presence or absence of open circuit between the first thrust detection coil and the third path based on the voltage value of the third signal and the third threshold value, and detects the presence or absence of open circuit between the second thrust detection coil and the fourth path based on the voltage value of the fourth signal and the fourth threshold value.

[0246] According to this configuration, the device can appropriately detect whether there is a disconnection in the first to fourth paths even if the voltage value of each composite signal increases over time.

[0247] A seventh embodiment of the present invention is a motor bearing wear monitoring device (e.g., motor bearing wear monitoring device (5A)) that monitors the wear condition of a bearing supporting the rotation axis of a rotor based on detection signals of each of a plurality of detection coils that detect a change in magnetic flux corresponding to a change in the mechanical position of the rotor relative to the stator of a motor of a canned motor pump, wherein the plurality of detection coils includes one group of radial detection coils that detect the change in magnetic flux in the radial direction of the rotation axis and one group of thrust detection coils that detect the change in magnetic flux in the thrust direction of the rotation axis, wherein in the thrust direction, the radial detection coil and the thrust detection coil are disposed at one end of the stator on the directional side or the other end, and the radial detection coil is electrically connected to a radial signal path through which a radial composite signal, formed by synthesizing the detection signals of each of the radial detection coils, flows, and the thrust detection coil is electrically connected to a thrust signal path through which a thrust composite signal, formed by synthesizing the detection signals of each of the thrust detection coils, flows. A voltage value storage unit that updates and stores a radial maximum voltage value that is the maximum value among the voltage values ​​of the radial composite signal and a thrust maximum voltage value that is the maximum value among the voltage values ​​of the thrust composite signal, an acquisition unit that acquires a radial path signal flowing through the radial signal path, a thrust path signal flowing through the thrust signal path, the radial maximum voltage value and the thrust maximum voltage value, and a machine-learned radial learning model (e.g., a first learning model (M1)) that estimates whether there is a disconnection between the radial detection coil and the radial signal path when the voltage value of the radial path signal and the radial maximum voltage value are input.A learning model storage unit (e.g., storage unit (54A)) that stores a machine-learned completed thrust learning model (e.g., third learning model (M3), fourth learning model (M4)) for estimating whether there is a disconnection between the thrust detection coil and the thrust signal path when the second learning model (M2)) and the voltage value of the thrust path signal and the thrust maximum voltage value are input, and a disconnection estimation unit (e.g., disconnection estimation unit (537)) that estimates whether there is a disconnection between each of the detection coil, the radial signal path, and the thrust signal path, wherein when the detection coil, the radial signal path, and the thrust signal path are not disconnected, the radial composite signal flows through the radial signal path as the radial path signal, and the thrust composite signal flows through the thrust signal path as the thrust path signal, and the disconnection estimation unit estimates the voltage value of the radial path signal and the radial maximum A motor bearing wear monitoring device that inputs a voltage value into the radial learning model to estimate whether there is a disconnection between the radial detection coil and the radial signal path, and inputs the voltage value of the thrust path signal and the thrust maximum voltage value into the thrust learning model to estimate whether there is a disconnection between the thrust detection coil and the thrust signal path.

[0248] According to this configuration, the device can automatically estimate whether there is a disconnection in the detection coil and the first to fourth paths without undergoing threshold processing.

[0249] The eighth embodiment of the present invention is a wire breakage detection program that enables a computer to function as a motor bearing wear monitoring device according to the first embodiment.

[0250] According to this configuration, the pump user can safely check for open circuits in the detection coil and paths 1 through 4 without stopping the pump.

[0251] The ninth embodiment of the present invention is a wire breakage estimation program that enables a computer to function as a motor bearing wear monitoring device according to the seventh embodiment.

[0252] According to this configuration, the device can automatically estimate whether there is a disconnection in the detection coil and the first to fourth paths without undergoing threshold processing.

[0253] The tenth embodiment of the present invention is a method for detecting a wire breakage (e.g., radial-side wire breakage detection processing (ST2), thrust-side wire breakage detection processing (ST3)) executed by a motor bearing wear monitoring device (e.g., motor bearing wear monitoring device (5)) which monitors the wear state of a bearing supporting the rotation axis of a rotor based on detection signals of each of a plurality of detection coils that detect a change in magnetic flux corresponding to a change in the mechanical position of the rotor relative to the stator of a canned motor pump, wherein the plurality of detection coils includes one group of radial detection coils that detect the change in magnetic flux in the radial direction of the rotation axis and one group of thrust detection coils that detect the change in magnetic flux in the thrust direction of the rotation axis, wherein in the thrust direction, the radial detection coil and the thrust detection coil are disposed at one end of the stator on the unidirectional side or the other end, and the radial detection coil is electrically connected to a radial signal path through which a radial composite signal, formed by synthesizing the detection signals of each of the radial detection coils, flows, and the thrust detection A coil is electrically connected to a thrust signal path through which a thrust composite signal, formed by synthesizing the detection signals of each of the thrust detection coils, flows, and the motor bearing wear monitoring device has a threshold value storage unit that stores a radial threshold value set to be smaller than the voltage value of the radial composite signal and a thrust threshold value set to be smaller than the voltage value of the thrust composite signal, and when each of the detection coil, the radial signal path, and the thrust signal path is not disconnected, the radial composite signal flows through the radial signal path as a radial path signal, and the thrust composite signal flows through the thrust signal path as a thrust path signal, and the disconnection detection method comprises an acquisition step in which the motor bearing wear monitoring device acquires the radial path signal from the radial signal path and acquires the thrust path signal from the thrust signal path (e.g.,A method for detecting open circuits, comprising a first acquisition step (ST21), a second acquisition step (ST31)), and an open circuit detection step (e.g., a first comparison step (ST22), a second comparison step (ST25), a third comparison step (ST32), and a fourth comparison step (ST35)) in which the motor bearing wear monitoring device detects the open circuit of each of the radial detection coil and the radial signal path based on the voltage value of the radial path signal and the radial threshold value, and detects the open circuit of each of the thrust detection coil and the thrust signal path based on the voltage value of the thrust path signal and the thrust threshold value.

[0254] According to this configuration, the pump user can safely check for open circuits in the detection coil and paths 1 through 4 without stopping the pump. Explanation of the symbols

[0255] 1 Cand Motor Pump 3 Motor section 31 Rotation axis 32 bearings 33 bearings 36 rotors 37 status 5 Motor bearing wear monitoring device 53a CPU (Processor) 53b RAM (threshold storage unit, voltage storage unit) 531 Wear amount detection unit 532 2nd Acquisition Department (Acquisition Department) 534 Threshold setting section 535 Open circuit detection unit 5A Motor Bearing Wear Monitoring Device 537 Estimated single-line section 54A Storage Unit (Learning Model Storage Unit) C1 detection coil (radial detection coil, first radial detection coil) C2 detection coil (thrust detection coil, first thrust detection coil) C3 detection coil (radial detection coil, first radial detection coil) C4 detection coil (thrust detection coil, first thrust detection coil) C5 detection coil (radial detection coil, second radial detection coil) C6 detection coil (thrust detection coil, second thrust detection coil) C7 detection coil (radial detection coil, second radial detection coil) C8 detection coil (thrust detection coil, second thrust detection coil) L1 First path (radial signal path) L2 Second Path (Radial Signal Path) L3 Third Path (Thrust Signal Path) L4 4th path (thrust signal path) M1 1st learning model (radial learning model) M2 Second Learning Model (Radial Learning Model) M3 Third Learning Model (Thrust Learning Model) M4 4th Learning Model (Thrust Learning Model)

Claims

Claim 1 A motor bearing wear monitoring device for monitoring the wear condition of a bearing supporting the rotation axis of a rotor based on detection signals of each of a plurality of detection coils that detect changes in magnetic flux corresponding to changes in the mechanical position of the rotor relative to the stator of a motor of a canned motor pump, wherein the plurality of detection coils include one group of radial detection coils that detect changes in magnetic flux in the radial direction of the rotation axis and one group of thrust detection coils that detect changes in magnetic flux in the thrust direction of the rotation axis, wherein in the thrust direction, the radial detection coil and the thrust detection coil are disposed at the end of the stator on one side or the other side, wherein the radial detection coil is electrically connected to a radial signal path through which a radial composite signal, formed by synthesizing the detection signals of each of the radial detection coils, flows, and the thrust detection coil is electrically connected to a thrust signal path through which a thrust composite signal, formed by synthesizing the detection signals of each of the thrust detection coils, flows, wherein a radial threshold value set to be smaller than the voltage value of the radial composite signal and the thrust composite signal The apparatus comprises a threshold storage unit that stores a thrust threshold value set to be smaller than a voltage value, an acquisition unit that acquires a radial path signal flowing through the radial signal path and a thrust path signal flowing through the thrust signal path, and a disconnection detection unit that detects whether there is a disconnection of each of the detection coil, the radial signal path, and the thrust signal path, and when the detection coil, the radial signal path, and the thrust signal path are not disconnected, the radial composite signal flows through the radial signal path as the radial path signal, and the thrust composite signal flows through the thrust signal path as the thrust path signal, and the disconnection detection unit detects whether there is a disconnection of the radial detection coil and the radial signal path based on the voltage value of the radial path signal and the radial threshold value.A motor bearing wear monitoring device that detects whether the thrust detection coil and the thrust signal path are disconnected based on the voltage value of the thrust path signal and the thrust threshold value. Claim 2 A motor bearing wear monitoring device according to claim 1, comprising a voltage value storage unit that updates and stores a radial maximum voltage value which is the maximum value among the voltage values ​​of the radial composite signal and a thrust maximum voltage value which is the maximum value among the voltage values ​​of the thrust composite signal, wherein the radial threshold value is set based on the radial maximum voltage value and the thrust threshold value is set based on the thrust maximum voltage value. Claim 3 A motor bearing wear monitoring device according to claim 2, wherein the radial threshold is set based on the signal level of a noise component included in the radial path signal, and the thrust threshold is set based on the signal level of a noise component included in the thrust path signal. Claim 4 In claim 3, the motor bearing wear monitoring device wherein the radial threshold is smaller than the thrust threshold. Claim 5 A motor bearing wear monitoring device having a threshold setting unit for setting each of the radial threshold and the thrust threshold in any one of claims 1 to 4. Claim 6 In claim 1, the plurality of detection coils includes a group of first radial detection coils and a group of second radial detection coils functioning as a group of radial detection coils, and a group of first thrust detection coils and a group of second thrust detection coils functioning as a group of thrust detection coils, wherein the first radial detection coil and the first thrust detection coil are disposed at the one-way end of the stator, and the second radial detection coil and the second thrust detection coil are disposed at the other-way end of the stator, and the radial signal path is electrically connected to the first radial detection coil and comprises a first path in which a first composite signal, formed by synthesizing the detection signals of each of the first radial detection coils, flows as the radial composite signal, and a second path in which a second composite signal, formed by synthesizing the detection signals of each of the second radial detection coils, flows as the radial composite signal, and the thrust signal The path is electrically connected to the first thrust detection coil and has a third path in which a third composite signal, formed by synthesizing the detection signals of each of the first thrust detection coils, flows as the thrust composite signal, and is electrically connected to the second thrust detection coil and has a fourth composite signal, formed by synthesizing the detection signals of each of the second thrust detection coils, flows as the thrust composite signal; the radial threshold includes a first threshold set to be smaller than the voltage value of the first composite signal and a second threshold set to be smaller than the voltage value of the second composite signal, and the thrust threshold includes a third threshold set to be smaller than the voltage value of the third composite signal and a fourth threshold set to be smaller than the voltage value of the fourth composite signal, and the acquisition unit acquires each of the first signal flowing through the first path and the second signal flowing through the second path as the radial path signal.Each of the third signal flowing through the third path and the fourth signal flowing through the fourth path is acquired as the thrust path signal, and when the detection coil, the first path, the second path, the third path, and the fourth path are not disconnected, the first composite signal flows through the first path as the first signal, the second composite signal flows through the second path as the second signal, the third composite signal flows through the third path as the third signal, and the fourth composite signal flows through the fourth path as the fourth signal, and the disconnection detection unit detects the presence or absence of disconnection between the first radial detection coil and the first path based on the voltage value of the first signal and the first threshold value, detects the presence or absence of disconnection between the second radial detection coil and the second path based on the voltage value of the second signal and the second threshold value, and the first thrust detection coil and the third path based on the voltage value of the third signal and the third threshold value A motor bearing wear monitoring device that detects the presence or absence of the above-mentioned disconnection and detects the presence or absence of the above-mentioned disconnection of the second thrust detection coil and the fourth path based on the voltage value of the fourth signal and the fourth threshold value. Claim 7 A motor bearing wear monitoring device for monitoring the wear condition of a bearing supporting the rotation axis of a rotor based on detection signals of each of a plurality of detection coils that detect changes in magnetic flux corresponding to changes in the mechanical position of the rotor relative to the stator of a motor of a canned motor pump, wherein the plurality of detection coils include one group of radial detection coils that detect changes in magnetic flux in the radial direction of the rotation axis and one group of thrust detection coils that detect changes in magnetic flux in the thrust direction of the rotation axis, wherein in the thrust direction, the radial detection coil and the thrust detection coil are disposed at the end of the stator on one side or the other side, wherein the radial detection coil is electrically connected to a radial signal path through which a radial composite signal, formed by synthesizing the detection signals of each of the radial detection coils, flows, and the thrust detection coil is electrically connected to a thrust signal path through which a thrust composite signal, formed by synthesizing the detection signals of each of the thrust detection coils, flows, wherein the radial maximum voltage value which is the maximum value among the voltage values ​​of the radial composite signal and the thrust A voltage value storage unit that updates and stores a thrust maximum voltage value that is the maximum value among the voltage values ​​of the composite signal; an acquisition unit that acquires a radial path signal flowing through the radial signal path, a thrust path signal flowing through the thrust signal path, the radial maximum voltage value, and the thrust maximum voltage value; a machine-learned radial learning model that estimates whether there is a disconnection between the radial detection coil and the radial signal path when the voltage value of the radial path signal and the radial maximum voltage value are input, and a machine-learned thrust learning model that estimates whether there is a disconnection between the thrust detection coil and the thrust signal path when the voltage value of the thrust path signal and the thrust maximum voltage value are input, a learning model storage unit that stores the detection coil, the radial signal path,A motor bearing wear monitoring device comprising: a disconnection estimation unit for estimating whether there is a disconnection in each of the thrust signal paths; wherein, when the detection coil, the radial signal path, and the thrust signal path are not disconnected, the radial composite signal flows through the radial signal path as the radial path signal, and the thrust composite signal flows through the thrust signal path as the thrust path signal; wherein the disconnection estimation unit inputs the voltage value of the radial path signal and the radial maximum voltage value into the radial learning model to estimate whether there is a disconnection in each of the radial detection coil and the radial signal path, and inputs the voltage value of the thrust path signal and the thrust maximum voltage value into the thrust learning model to estimate whether there is a disconnection in each of the thrust detection coil and the thrust signal path. Claim 8 A wire break detection program that enables a computer to function as a motor bearing wear monitoring device according to claim 1. Claim 9 A wire breakage estimation program that enables a computer to function as a motor bearing wear monitoring device according to Article 7. Claim 10 A method for detecting a broken wire executed by a motor bearing wear monitoring device that monitors the wear state of a bearing supporting the rotation axis of a rotor based on detection signals of each of a plurality of detection coils that detect a change in magnetic flux corresponding to a change in the mechanical position of the rotor relative to the stator of a canned motor pump, wherein the plurality of detection coils include one group of radial detection coils that detect the change in magnetic flux in the radial direction of the rotation axis and one group of thrust detection coils that detect the change in magnetic flux in the thrust direction of the rotation axis, wherein in the thrust direction, the radial detection coil and the thrust detection coil are disposed at the end of the stator on one side or the other side, wherein the radial detection coil is electrically connected to a radial signal path through which a radial composite signal, formed by synthesizing the detection signals of each of the radial detection coils, flows, and the thrust detection coil is electrically connected to a thrust signal path through which a thrust composite signal, formed by synthesizing the detection signals of each of the thrust detection coils, flows, and wherein the motor bearing wear monitoring device is set to be smaller than the voltage value of the radial composite signal. A threshold storage unit storing a radial threshold and a thrust threshold set to be smaller than the voltage value of the thrust composite signal, wherein when the detection coil, the radial signal path, and the thrust signal path are not disconnected, the radial composite signal flows through the radial signal path as a radial path signal, and the thrust composite signal flows through the thrust signal path as a thrust path signal, and the disconnection detection method comprises an acquisition step in which the motor bearing wear monitoring device acquires the radial path signal from the radial signal path and acquires the thrust path signal from the thrust signal path, and the motor bearing wear monitoring device detects the disconnection of the radial detection coil and the radial signal path based on the voltage value of the radial path signal and the radial threshold.A method for detecting a broken wire, comprising a broken wire detection step of detecting a broken wire in each of the thrust detection coil and the thrust signal path based on the voltage value of the thrust path signal and the thrust threshold value.

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