Vibration detection device, electric motor unit, fan, and air treatment device

Abstract

To provide a vibration detection device which offers an increased frequency band available for vibration detection of rotary machinery.SOLUTION: A vibration detection device is provided, comprising a first detection unit (40) for detecting vibration of an electric motor (15a) in a first frequency band, a second detection unit (50) for detecting vibration of the rotary machine (15a) in a second frequency band different from the first frequency band, and a processing unit (60) configured to measure the vibration of the electric motor (15a) using detection signals from the first detection unit (40) and the second detection unit (50).SELECTED DRAWING: Figure 4

Description

Technical Field

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[0001] The present disclosure relates to a vibration detection device applied to a rotating machine.

Background Art

[0002] Patent Document 1 discloses a vibration sensor (vibration detection device) that detects vibration. The vibration sensor has a piezoelectric element and a weight attached to the piezoelectric element. When vibration acts on the vibration sensor, the vibration of the weight is transmitted to the piezoelectric element, and a detection signal corresponding to the vibration is output from the piezoelectric element.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] It is conceivable to apply a vibration detection device such as that of Patent Document 1 to a rotating machine such as an electric motor. However, with the vibration detection device described in Patent Document 1, it is difficult to fully cover the frequency band of the vibration of the rotating machine and to sufficiently measure the vibration of the rotating machine.

[0005] An object of the present disclosure is to provide a vibration detection device capable of expanding the frequency band in which the vibration of a rotating machine can be detected.

Means for Solving the Problems

[0006] The first aspect is directed to a vibration detection device, a first detection unit (40) that detects vibration in a first frequency band in a rotating machine (15a), a second detection unit (50) that detects vibration in a second frequency band different from the first frequency band in the rotating machine (15a), [[ID=The system includes a processing unit (60) that measures the vibration of the rotating machine (15a) based on the detection signals from the first detection unit (40) and the second detection unit (50).

[0007] In the first embodiment, the first detection unit (40) and the second detection unit (50) detect vibrations in different frequency bands in the rotating machine (15a). This expands the frequency band in which vibrations of the rotating machine (15a) can be detected.

[0008] A second aspect is, in the first aspect, The system comprises a module (M) on which the first detection unit (40) and the second detection unit (50) are provided.

[0009] In the second embodiment, since the first detection unit (40) and the second detection unit (50) are provided in the same module (M), the positions where the first detection unit (40) and the second detection unit (50) detect vibration can be brought closer together. This improves the accuracy of detecting vibrations of the electric motor (15a).

[0010] A third aspect is, in the second aspect, The first detection unit (40) and the second detection unit (50) have portions that overlap each other in a predetermined direction. In the third embodiment, since the first detection unit (40) and the second detection unit (50) overlap in a predetermined direction, the positions in which the first detection unit (40) and the second detection unit (50) detect vibration can be brought even closer together.

[0011] A fourth aspect is, in the third aspect, The module (M) has substrates (31, 32) on which the first detection unit (40) and the second detection unit (50) are provided. The first detection unit (40) and the second detection unit (50) have portions that overlap each other in the thickness direction of the substrate (31, 32).

[0012] Here, the overlapping portions in the thickness direction refer to both cases: when the first detection unit (40) and the second detection unit (50) overlap in the thickness direction while in contact, and when the first detection unit (40) and the second detection unit (50) overlap in the thickness direction while separated.

[0013] In the fourth aspect, the first detection unit (40) and the second detection unit (50), on which the substrates (31, 32) are provided, overlap in the thickness direction of the substrates (31, 32), so that the positions where the first detection unit (40) and the second detection unit (50) detect vibration can be brought even closer together.

[0014] The fifth aspect is as described in the fourth aspect. The first detection unit (40) is a piezoelectric sensor (40), The aforementioned substrates (31, 32) First substrate (31), The system includes a second substrate (32) which is stacked in the thickness direction of the first substrate (31) via the piezoelectric sensor (40).

[0015] In the fifth embodiment, by stacking the second substrate (32) on the piezoelectric sensor (40), the second substrate (32) can function as a weight that promotes deformation of the piezoelectric sensor (40).

[0016] The sixth aspect is as described in the fifth aspect. The piezoelectric sensor (40) has a piezoelectric film (41) and electrodes (42, 43) formed on the surface of the piezoelectric film (41), On the first surface (S1) of the second substrate (32) on the piezoelectric sensor (40) side, metal foils (C3, C4) that contact the electrodes (42, 43) are formed.

[0017] In the sixth embodiment, the metal foils (C3, C4) of the second substrate (32) can be used as the conductive parts of the electrodes (42, 43) of the piezoelectric sensor (40). The electrodes (42, 43) can be electrically connected to the metal foils (C3, C4) as conductive parts without using soldering or the like.

[0018] The seventh aspect is, in the fifth or sixth aspect, a first current-carrying member (33) that connects the first substrate (31) and one end portion in the direction along the first surface of the second substrate (32); and a second current-carrying member (34) that connects the first substrate (31) and the other end portion in the direction along the first surface of the second substrate (32).

[0019] In the seventh aspect, by providing the first current-carrying member (33) and the second current-carrying member (34) at both end portions of the second substrate (32), it is possible to suppress the deformation of the second substrate (32) functioning as a weight in the thickness direction from being obstructed by the first current-carrying member (33) and the second current-carrying member (34).

[0020] The eighth aspect is, in any one of the fifth to seventh aspects, the second detection unit (50) is a semiconductor sensor (50) having a semiconductor chip (51) and a sensor casing (52) that houses the semiconductor chip (51), and the semiconductor sensor (50) is mounted on the second substrate (32).

[0021] In the eighth aspect, the semiconductor sensor (50) having the sensor casing (52) is mounted on the second substrate (32). Thereby, in addition to the second substrate (32), the semiconductor sensor (50) can be made to function as a weight that promotes the deformation of the piezoelectric sensor (40).

[0022] The ninth aspect is, in the eighth aspect, the semiconductor sensor (50) is a MEMS type sensor (50).

[0023] In the ninth aspect, by using a semiconductor sensor functioning as a weight as a MEMS type sensor (50), the detection accuracy of vibration can be improved.

[0024] The tenth aspect is, in the fifth to seventh aspects, the first detection unit (40) and the second detection unit (50) are mounted on the first substrate (31).

[0025] In the tenth embodiment, the first detection unit (40) and the second detection unit (50) are not mounted on the second substrate (32). Therefore, deformation of the second substrate (32) in the thickness direction during manufacturing can be suppressed, and the second substrate (32) can be easily processed.

[0026] The eleventh aspect is one of the second to tenth aspects, The module (M) is equipped with a conversion unit (67, 72, 73, 74) that converts at least one of the detection signals from the first detection unit (40) and the second detection unit (50) from an analog signal to a digital signal.

[0027] In the eleventh embodiment, the first detection unit (40), the second detection unit (50), and the conversion units (67, 72, 73, 74) are provided in the same module (M). The conversion units (67, 72, 73, 74) convert the detection signals of the first detection unit (40) and the second detection unit (50) from analog signals to digital signals, thereby suppressing the superposition of external noise on these detection signals.

[0028] The twelfth aspect is as follows, in the eleventh aspect: The processing unit (60) is mounted in the module (M).

[0029] In the twelfth embodiment, the first detection unit (40), the second detection unit (50), and the processing unit (60) are provided in the same module (M). Therefore, wiring cables from the first detection unit (40) and the second detection unit (50) to the processing unit (60) can be eliminated, and the superposition of external noise on the detection signal can be suppressed.

[0030] The 13th aspect is one of the first to 12 aspects, The aforementioned processing unit (60) is Based on the detection signal from the first detection unit (40) and the detection signal from the second detection unit (50) stored in the memory unit (71), signal processing is performed. Outputs the signal after it has been processed.

[0031] In the 13th embodiment, the detection signal stored in the memory unit (71) can be subjected to predetermined signal processing before the necessary signal can be output.

[0032] The 14th aspect is one of the first to 13 aspects, The first detection unit (40) detects vibrations in the first direction in the rotating machine (15a), The second detection unit (50) is The rotating machine (15a) is configured to detect vibrations in the first direction and vibrations in the second direction perpendicular to the first direction, or to detect vibrations in the rotating machine (15a) in the first direction, vibrations in the second direction, and vibrations in the third direction perpendicular to the first and second directions.

[0033] In the 14th embodiment, in addition to vibrations of the rotating machine (15a) in the first direction, vibrations in a second direction perpendicular to the first direction and vibrations in a third direction perpendicular to both the first and second directions can be detected.

[0034] The 15th aspect is one of the first to 14 aspects, The detection signal from the first detection unit (40) and the detection signal from the second detection unit (50) have overlapping frequency bands. The processing unit (60) subtracts the vibration value of the detection signal from the second detection unit (50) from the vibration value of the detection signal from the first detection unit (40), and measures the vibration of the rotating machine (15a) based on the signal after the subtraction.

[0035] In the 15th embodiment, signals from the first detection unit (40) and the second detection unit (50) that overlap in frequency band can be removed, so that the vibration of the rotating machine (15a) can be measured based on signals in a desired frequency band.

[0036] The 16th aspect is, The aforementioned rotating machine is an electric motor (15a), A vibration detection device (30) as described in any one of the first to fifteenth descriptions is provided. There is an electric motor unit.

[0037] The 17th aspect is, This is a fan equipped with the electric motor unit (U) described in 16.

[0038] The 18th aspect is, This is an air treatment device equipped with the electric motor unit (U) described in paragraph 16. [Brief explanation of the drawing]

[0039] [Figure 1] Figure 1 is a schematic diagram of the air treatment device. [Figure 2] Figure 2 is a perspective view showing the schematic configuration of the fan and vibration damping device. [Figure 3] Figure 3 is a schematic block diagram of the air treatment device. [Figure 4] Figure 4 is a perspective view showing the schematic configuration of the vibration detection device. [Figure 5] Figure 5 is a longitudinal cross-sectional view of the vibration detection device module. [Figure 6] Figure 6 is a circuit diagram of the vibration detection device. [Figure 7] Figure 7 is a block diagram showing the functional elements of the processing unit. [Figure 8] Figure 8 is a flowchart of the calibration process. [Figure 9] Figure 9 is a flowchart of the anomaly detection process. [Figure 10] Figure 10 is a longitudinal cross-sectional view of the vibration detection device module of Modified Example 1. [Figure 11] Figure 11 is a circuit diagram of a modified example 2 of the vibration detection device. [Modes for carrying out the invention]

[0040] 《Embodiment》 The embodiments of this disclosure will be described in detail below with reference to the drawings. However, this disclosure is not limited to the embodiments shown below, and various modifications are possible without departing from the technical idea of ​​this disclosure. Since the drawings are for conceptual illustration of this disclosure, dimensions, ratios, or numbers may be exaggerated or simplified as necessary for ease of understanding.

[0041] (1) Air treatment device The vibration detection device (30) of this disclosure is applied to the electric motor (15a) of the air treatment device (10). Specifically, the vibration detection device (30) is applied to the electric motor (15a) of the fan (15).

[0042] The air treatment device (10) in this embodiment is an air handling unit. The air treatment device (10) is configured to control the temperature and humidify the air. The air treatment device (10) is installed in a building such as a building and constitutes part of an air conditioning system.

[0043] As shown in Figure 1, the air treatment device (10) comprises a casing (11) and a plurality of elements housed within the casing (11). The plurality of elements include a filter (12), a heat exchanger (13), a humidifying element (14), and a fan (15).

[0044] The casing (11) is formed in the shape of a hollow rectangular parallelepiped. An inlet (11a) and an outlet (11b) are formed on the top plate of the casing (11). Inside the casing (11), an air passage (11c) is formed between the inlet (11a) and the outlet (11b). In the air passage (11c), a filter (12), a heat exchanger (13), a humidifying element (14), and a fan (15) are arranged in order from the upstream side to the downstream side in the direction of airflow.

[0045] The filter (12) collects dust from the air. The heat exchanger (13) exchanges heat between water supplied from a heat source device (not shown) and the air flowing through the air passage (11c). The humidifying element (14) humidifies the air by bringing the supplied water into contact with the air and vaporizing it.

[0046] The fan (15) shown in Figures 1 and 2 is, for example, a sirocco fan. The fan (15) has an impeller and an electric motor (15a) that drives the impeller. The electric motor (15a) is an example of a rotating machine of the present disclosure. The electric motor (15a) is an AC motor. The electric motor (15a) is positioned so that its axis extends in a substantially horizontal direction. The electric motor (15a) is configured to have a variable rotational speed by being controlled by an inverter (18) shown in Figure 3.

[0047] A vibration damping device (16) is provided on the underside of the fan (15). The vibration damping device (16) has a vibration damping platform (16a) and a plurality of vibration damping rubbers (16b). The vibration damping platform (16a) supports the fan (15) from below. The vibration damping rubbers (16b) are installed on the bottom plate of the casing (11) and support the vibration damping device (16) from below. The vibration damping rubbers (16b) are made of an elastic material and reduce vibrations of the electric motor (15a). The vibration damping rubbers (16b) particularly reduce horizontal vibrations of the electric motor (15a).

[0048] When the air treatment device (10) is in operation, the fan (15) is also in operation. Air is drawn in from the inlet (11a) into the air passage (11c) and passes through the filter (12) and the heat exchanger (13) in sequence. In the heat exchanger (13), the air is cooled or heated by water. The air whose temperature has been regulated in the heat exchanger (13) is humidified by the humidifying element (14). The humidified air is supplied from the outlet (11b) to a predetermined target space.

[0049] As shown in Figure 3, the air treatment device (10) includes a control unit (17), an inverter (18), and a display unit (19).

[0050] The control unit (17) includes a microprocessor, electrical circuits, and electronic circuits. The microprocessor includes a CPU (Central Processing Unit), memory, a communication interface, analog input / output, and a contact input / output interface. The memory stores various programs for the CPU to execute and data used by the programs. The control unit (17) controls the electric motor (15a). Specifically, the control unit (17) adjusts the operating frequency of the electric motor (15a) by controlling the ON / OFF state of the switching elements of the inverter (18). The control unit (17) receives a signal from the vibration detection device (30). In response to this signal, the control unit (17) outputs a signal to the display unit (19) to display an abnormality in the electric motor (15a).

[0051] The display unit (19) is connected to the control unit (17) by wire or wireless connection. The display unit (19) is an example of a notification unit that informs a person of an abnormal condition of the electric motor (15a). The display unit (19) informs a person of an abnormal condition of the electric motor (15a) in response to a signal received from the control unit (17). The display unit (19) consists of an LED, a display, a touch panel, a smartphone, or a tablet terminal. The notification unit may also notify the person of an abnormal condition of the electric motor (15a) by sound. The notification unit may also notify the person of an abnormal condition of the electric motor (15a) in response to a signal received directly from the vibration detection device (30).

[0052] (2) Structure of the vibration detection device (2-1) Mounting position The vibration detection device (30) measures the vibration of the electric motor (15a). As shown in Figure 2, the vibration detection device (30) is attached to the upper end of the outer surface of the electric motor (15a). This makes it easier for the vibration detection device (30) to detect vibrations in the Z-axis direction (vertical direction as shown in Figure 2) of the electric motor (15a). The vibration detection device (30) may also be attached to the lower end of the outer surface of the electric motor (15a), or to other parts of the electric motor (15a).

[0053] The electric motor (15a) and the vibration detection device (30) constitute the electric motor unit (U).

[0054] (2-2) Outline configuration of the vibration detection device As shown in Figures 4 and 5, the vibration detection device (30) includes a module (M), a piezoelectric sensor (40), an acceleration sensor (50), an MPU (Micro Processor Unit) (60), and a communication connector (61). The module (M) includes a first substrate (31) and a second substrate (32). In Figure 4, the Z-axis direction is the vertical direction and corresponds to the first direction of this disclosure. The X-axis direction is the front-to-back direction of the horizontal direction and corresponds to the second direction of this disclosure. The Y-axis direction is the left-to-right direction of the horizontal direction and corresponds to the third direction of this disclosure. The X-axis, Y-axis, and Z-axis directions are orthogonal to each other.

[0055] (2-2-1) First substrate The first substrate (31) is a printed circuit board that is a main component of the module (M). The first substrate (31) is fixed to the electric motor (15a) via a housing or other component. In this example, the first substrate (31) is a double-sided printed circuit board (2-layer substrate). The first substrate (31) is formed in the shape of a rectangular plate with the X-axis direction being the longer side and the Y-axis direction being the shorter side. The thickness direction of the first substrate (31) corresponds to the Z-axis direction. The MPU (60) and the communication connector (61) are mounted on the first surface (S1) (top surface) of the first substrate (31).

[0056] (2-2-2) Second board The second substrate (32) is a printed circuit board that serves as a sub-component of the module (M). In this example, the second substrate (32) is a double-sided printed circuit board (two-layer substrate). The second substrate (32) is attached to the third surface (S3) (top surface) of the first substrate (31). The second substrate (32) is formed in the shape of a rectangular plate with the longer side in the X-axis direction and the shorter side in the Y-axis direction. The thickness direction of the second substrate (32) corresponds to the Z-axis direction. An acceleration sensor (50) is mounted on the third surface (S3) of the second substrate (32). The second substrate (32) is supported by the first substrate (31) via a plurality of pins (33, 34) while being separated from the first substrate (31). The plurality of pins (33, 34) are an example of the conductive members of this disclosure.

[0057] (2-2-3) Piezoelectric Sensor A piezoelectric sensor (40) is an example of the first detection unit of this disclosure. The piezoelectric sensor (40) detects vibrations in the Z-axis direction as the first direction in the electric motor (15a). The piezoelectric sensor (40) has a piezoelectric film (41), a first electrode (42), and a second electrode (43). The piezoelectric film (41) is formed as a thin film extending in the X-axis direction.

[0058] The piezoelectric film (41) is made of a resin material that has a piezoelectric effect. The piezoelectric film (41) is formed in a rectangular shape with the X-axis direction being the longer side and the Y-axis direction being the shorter side. However, the shape of the piezoelectric film is not limited to this, and it may be square, for example. The thickness direction of the piezoelectric film (41) corresponds to the Z-axis direction. The piezoelectric film (41) is configured to be elastically deformable in its thickness direction (Z-axis direction).

[0059] A first electrode (42) is formed on one surface (top surface) in the thickness direction of the piezoelectric film (41). A second electrode (43) is formed on the other surface (bottom surface) of the piezoelectric film (41). The first electrode (42) and the second electrode (43) constitute electrodes formed on the piezoelectric film (41) by metal deposition or metal paste. The piezoelectric sensor (40) generates a voltage as the piezoelectric film (41) deforms in the thickness direction due to vibration and outputs a detection signal corresponding to the vibration.

[0060] (2-2-4) Accelerometer An acceleration sensor (50) is an example of a second detection unit of the present disclosure. The acceleration sensor (50) of the present disclosure detects vibrations in the X-axis and Y-axis directions in addition to vibrations in the Z-axis direction of the electric motor (15a). The acceleration sensor (50) is a MEMS (Micro Electro Mechanical Systems) type semiconductor sensor. The acceleration sensor (50) has a semiconductor chip (51) and a sensor casing (52) that houses the semiconductor chip (51). The sensor casing (52) is made of resin, metal, or ceramic. The sensor casing (52) is formed in the shape of a rectangular parallelepiped, with a height in the Z-axis direction being smaller than the length in the X-axis and Y-axis directions.

[0061] (2-2-5) MPU and communication connector The Micro-Processing Unit (MPU) (60) is mounted on the first surface (S1) of the first substrate (31). The MPU (60) is an example of the processing unit of this disclosure. The MPU (60) performs predetermined signal processing on the detection signals detected by the piezoelectric sensor (40) and the acceleration sensor (50).

[0062] The communication connector (61) is mounted on the first surface (S1) of the first substrate (31). The communication connector (61) is located at the end of the first substrate (31) in the X-axis direction. The communication connector (61) outputs signals from the MPU (60) to the outside (more precisely, the control unit (17)) via the communication line (W), or inputs data from the control unit (17) and outputs it to the MPU (60).

[0063] (2-2-6) pins Module (M) includes a plurality of first pins (33) and a plurality of second pins (34). The first pins (33) are an example of a first energizing member of the disclosure, and the second pins (34) are an example of a second energizing member of the disclosure. The plurality of first pins (33) are provided at one end of the second substrate (32) in the X-axis direction (longitudinal direction). The plurality of first pins (33) are arranged along the short side of one end of the second substrate (32). The plurality of second pins (34) are provided at the other end of the second substrate (32) in the X-axis direction (longitudinal direction). The plurality of second pins (34) are arranged along the short side of the other end of the second base end. The plurality of first pins (33) may be, for example, seven, but may be one, or a plurality of other numbers. The plurality of second pins (34) may be, for example, seven, but may be one, or a plurality of other numbers.

[0064] The first pin (33) is connected between the first substrate (31) and the second substrate (32). The second pin (34) is connected between the first substrate (31) and the second substrate (32). The first pin (33) and the second pin (34) are fixed to the first substrate (31) and the second substrate (32) by screw fixing, press fitting, soldering, etc.

[0065] (2-2-7) Configuration of the power supply path As shown in Figure 5, the first substrate (31) of this disclosure has a first copper foil (C1) formed on its upper first surface (S1) and a second copper foil (C2) formed on its lower second surface (S2). A piezoelectric sensor (40) is provided on the first surface (S1) of the first substrate (31). An acceleration sensor (50) is provided on the upper third surface (S3) of the second substrate (32). A third copper foil (C3) is formed on the lower fourth surface (S4) of the second substrate (32). The first copper foil (C1), the second copper foil (C2), and the third copper foil (C3) are composed of conductive metal foils.

[0066] The first electrode (42) of the piezoelectric sensor (40) is in contact with the third copper foil (C3). This allows the third copper foil (C3) to function as the conductive part of the first electrode (42). Since current can be conducted between the first electrode (42) and the third copper foil (C3) by bringing them into contact, soldering or the like is not required.

[0067] The third copper foil (C3) conducts to the ground (GND) signal, which is the reference voltage of the first substrate (31), via the first pin (33) and the second pin (34) of the module (M) that corresponds to the reference voltage (0V). This allows the first electrode (42) to be used as a ground electrode. In addition, the third copper foil (C3) functions as a shield to block noise from the piezoelectric sensor (40).

[0068] The second copper foil (C2) conducts to the ground (GND) signal via the first pin (33) and the second pin (34) of the module (M), which is the reference voltage (0V). As a result, the second copper foil (C2) functions as a shield to block noise from the piezoelectric sensor (40). In this way, the piezoelectric sensor (40) is sandwiched between the shielding second copper foil (C2) and third copper foil (C3) in its thickness direction. This effectively blocks the effects of noise on the piezoelectric sensor (40) and improves the detection accuracy of the piezoelectric sensor (40) signal.

[0069] The second electrode (43) of the piezoelectric sensor (40) is in contact with the first copper foil (C1). This allows the first copper foil (C1) to function as the current-carrying part of the second electrode (43). Since current can be conducted between the second electrode (43) and the first copper foil (C1) by bringing them into contact, soldering or the like is not required. The second electrode (43) is electrically connected to the MPU (60) via the first copper foil (C1) and a conductive part (not shown) formed on the first substrate (31).

[0070] The acceleration sensor (50) is electrically connected to the MPU (60) via the signal input / output pins among the first pin (33) and second pin (34), and via conductive parts (wiring patterns) formed on the second substrate (32).

[0071] (2-2-8) Structure related to the weight The second substrate (32) is in contact with the upper surface of the piezoelectric sensor (40). Therefore, the second substrate (32) functions as a weight to promote deformation of the piezoelectric film (41). This improves the sensitivity of the piezoelectric film (41) in detecting vibrations in the Z-axis direction.

[0072] The acceleration sensor (50) is mounted on the second substrate (32). The acceleration sensor (50) has a sensor casing (52) and has a certain amount of weight. In addition, the acceleration sensor (50) is of the MEMS type and has a certain amount of weight. Therefore, the acceleration sensor (50) functions as a weight to promote deformation of the piezoelectric film (41). This improves the sensitivity of the piezoelectric film (41) in detecting vibrations in the Z-axis direction.

[0073] (2-2-9) Relative position of piezoelectric sensor and accelerometer The piezoelectric sensor (40) and the acceleration sensor (50) have overlapping portions in the thickness direction of the first substrate (31) or the second substrate (32). In this example, the entire acceleration sensor (50) overlaps with the piezoelectric sensor (40). This allows the vibration detection positions of the piezoelectric sensor (40) and the acceleration sensor (50) to be brought closer together.

[0074] The acceleration sensor (50), which functions as a counterweight, is located in the middle of the piezoelectric sensor (40) in the longitudinal direction. This allows for deformation of the piezoelectric sensor (40) in the thickness direction. It is preferable to align the center of gravity of the acceleration sensor (50) with the center of gravity of the piezoelectric sensor (40).

[0075] (2-3) Circuit configuration of the vibration detection device The circuit configuration of the vibration detection device (30) will be explained in detail with reference to Figure 6.

[0076] The vibration detection device (30) includes a first buffer amplifier (62), a first preamplifier (63), an MPU (60), a second buffer amplifier (64), and a driver / receiver (65). The MPU (60) includes a CPU (Central Processing Unit) (66), a first A / D converter (67), a D / A converter (68), a first serial communication unit (69), a second serial communication unit (70), and a storage unit (71).

[0077] The piezoelectric sensor (40) in this example outputs a detection signal based on the vibration of the electric motor (15a) as an analog signal. The piezoelectric sensor (40) is connected to a first A / D converter (67) via a first buffer amplifier (62) and a first preamplifier (63). The first A / D converter (67) is the converter of this disclosure and outputs a digital signal converted from the analog signal to a CPU (66).

[0078] The acceleration sensor (50) outputs a detection signal based on the vibration of the electric motor (15a) as a digital signal. More precisely, this detection signal includes a detection signal corresponding to the Z-axis direction, a detection signal corresponding to vibration in the X-axis direction, and a detection signal corresponding to vibration in the Y-axis direction. The acceleration sensor (50) is connected to the first serial communication unit (69) via serial communication. The first serial communication unit (69) transmits the received digital signal to the CPU (66).

[0079] The CPU (66) performs signal processing based on each received detection signal.

[0080] The memory unit (71) is composed of, for example, SRAM (Static Random Access Memory), DRAM (Dynamic Random Access Memory), flash memory, EEPROM (Electrically Erasable Programmable Read-Only Memory), etc. The memory unit (71) stores the detection signal from the piezoelectric sensor (40) and the detection signal from the acceleration sensor (50). The memory unit (71) also stores the calculation results from the CPU (66) and the detection signal after signal processing by the CPU (66).

[0081] The D / A conversion unit (68) is connected to the analog output unit (61a) of the communication connector (61) via the second buffer amplifier (64). The D / A conversion unit (68) converts the digital signals output from the CPU (66) and memory unit (71) into analog signals. The second buffer amplifier (64) has the function of differentially transmitting the signals to be output. The analog output unit (61a) outputs the analog signal to the outside (control unit (17)).

[0082] The second serial communication unit (70) is connected to the digital input / output unit (61b) of the communication connector (61) via a driver / receiver (65). Digital signals are transmitted bidirectionally between the second serial communication unit (70) and the digital input / output unit (61b). The driver / receiver (65) is made up of an integrated circuit and has the function of differentially transmitting the signals it outputs. The digital input / output unit (61b) outputs digital signals to the control unit (17). Digital signals from the control unit (17) are input to the digital input / output unit (61b).

[0083] (2-4) Functional configuration of the processing unit As shown in Figure 7, the MPU (60), which is the processing unit, has the following functional elements: an input unit (90), an arithmetic unit (91), a setting unit (92), a determination unit (93), and an output unit (94).

[0084] The input unit (90) receives the detection signal from the piezoelectric sensor (40) and the detection signal from the acceleration sensor (50).

[0085] The calculation unit (91) performs signal processing on the detection signals from the piezoelectric sensor (40) and the acceleration sensor (50). The calculation unit (91) calculates peak values ​​and RMS values ​​based on the detection signals in the Z-axis, X-axis, and Y-axis directions. The setting unit (92) is set with judgment values ​​for detecting abnormalities and other indicators for signal processing (such as the carrier frequency of the inverter (18)). The determination unit (93) makes an abnormality determination of the motor (15a) based on the calculation results of the calculation unit (91). The output unit (94) outputs an abnormality signal when the determination unit (93) determines that the conditions indicating that the motor (15a) is abnormal have been met. Details of these processes will be described later.

[0086] (3) Frequency band of detection signals from piezoelectric sensors and acceleration sensors The piezoelectric sensor (40) is configured to detect vibrations in a first frequency band in the electric motor (15a). The piezoelectric sensor (40) substantially detects vibrations only in the Z-axis direction, and does not detect vibrations in the X-axis and Y-axis directions. In this example, the piezoelectric sensor (40) is configured to detect vibrations in a first frequency band, for example, between 1 Hz and 100 kHz.

[0087] The sensitivity of the detection signal of the piezoelectric sensor (40) is affected by the impedance becoming high in the frequency band below a predetermined frequency (100 Hz). Specifically, below 100 Hz, the impedance exceeds 1 MΩ. As a result, a large amount of noise is superimposed on the detection signal in the frequency band below 100 Hz. On the other hand, the sensitivity of the detection signal of the piezoelectric sensor (40) is attenuated in the frequency band above a predetermined frequency (10 kHz). Therefore, the piezoelectric sensor (40) can accurately detect vibration signals, especially in the frequency band between 100 Hz and 10 kHz.

[0088] The acceleration sensor (50) is configured to detect vibrations in the second frequency band in the electric motor (15a). The acceleration sensor (50) detects vibrations in the second frequency band in the Z-axis, X-axis, and Y-axis directions, respectively. In this example, the acceleration sensor (50) is configured to detect vibrations in the second frequency band between 1 Hz and 3 kHz.

[0089] The sensitivity of the detection signal in the Z-axis direction of the acceleration sensor (50) is attenuated in frequency bands higher than a predetermined frequency band (3 kHz). Therefore, the acceleration sensor (50) can accurately detect vibration signals, especially in the frequency band between 1 Hz and 3 kHz. This is also true for the X-axis and Y-axis directions of the acceleration sensor (50).

[0090] (4) Operation of the vibration detection device The operation of the vibration detection device (30) will now be described. The vibration detection device (30) performs a calibration operation as its first operation and an abnormality detection operation as its second operation. The abnormality detection operation is an operation that detects abnormalities in the motor (15a) based on the natural vibration value of the motor (15a) during operation.

[0091] (4-1) Calibration operation The calibration operation is an operation to match the sensitivity of the piezoelectric sensor (40) and the acceleration sensor (50) in the low frequency band. The vibration detection device (30) performs the calibration operation before the abnormality detection operation. The vibration detection device (30) performs the calibration operation while the electric motor (15a) is stopped.

[0092] As shown in Figure 8, in step S11, the MPU (60) receives a detection signal from the piezoelectric sensor (40). This detection signal is a digital signal after conversion by the first A / D converter (67). In step S12, the MPU (60) receives a detection signal from the acceleration sensor (50). In this example, this detection signal is a digital signal. In step S13, the MPU (60) compares the output value of the detection signal received from the piezoelectric sensor (40) with the output value of the detection signal in the Z-axis direction received from the acceleration sensor (50) in a predetermined frequency band D (frequency band of 100 Hz or less) set in the setting unit (92). As described above, this frequency band D is the band in which the sensitivity of the piezoelectric sensor (40) becomes excessively high. If the output values ​​of the two signals are not equal in step S13, the process moves to step S14. In step S14, the MPU (60) performs gain adjustment and offset adjustment of both signals. Specifically, in step S14, the MPU (60) adjusts the gain and offset of both signals so that the output values ​​of the signal waveforms of both signals match in the frequency band D described above. In step S14, if the output values ​​of both are equal, the MPU (60) terminates the calibration operation. As a result, the sensitivity of the piezoelectric sensor (40) and the acceleration sensor (50) can be matched in the frequency band D.

[0093] Note that the gain adjustment and offset adjustment in step S14 do not necessarily have to be performed automatically by the MPU(60); they may also be performed manually from the preamplifier circuit or serial signal.

[0094] (4-2) Anomaly detection operation The abnormality detection operation is an operation that detects abnormalities in the electric motor (15a) based on detection signals from the piezoelectric sensor (40) and the acceleration sensor (50).

[0095] The vibration detection device (30) performs an abnormality detection operation while the electric motor (15a) is in operation. The vibration detection device (30) performs an abnormality detection operation after the calibration operation described above.

[0096] As shown in Figure 9, in step S21, the calculation unit (91) subtracts the vibration value of the detection signal in the Z-axis direction of the acceleration sensor (50) from the vibration value of the detection signal of the piezoelectric sensor (40). Specifically, for both detection signals after the calibration operation described above, the vibration value (output value) of the detection signal of the acceleration sensor (50) is subtracted from the vibration value (output value) of the detection signal of the piezoelectric sensor (40). Here, the output values ​​of both used for subtraction are based on data stored in the storage unit (71) at the same time.

[0097] As described above, the piezoelectric sensor (40) has excessively high sensitivity in frequency bands smaller than 100 Hz, for example, and therefore cannot accurately detect vibrations of the motor (15a). On the other hand, the acceleration sensor (50) has the characteristic of detecting vibrations in such frequency bands. For this reason, in frequency band D, by subtracting the vibration value of the Z-axis direction detection signal of the acceleration sensor (50) from the vibration value of the detection signal of the piezoelectric sensor (40), the detection signal of the piezoelectric sensor (40) with excessively high sensitivity in frequency bands can be excluded. In addition, by excluding the detection signal of frequency band D from the detection signal of the piezoelectric sensor (40), vibrations in the rotation frequency band associated with the rotation of the motor (15a) and low-frequency vibrations due to effects such as earthquakes can be excluded from the detection signal.

[0098] In step S22, the detection signal after subtraction following step S21 is combined with the detection signal from the acceleration sensor (50) in the Z-axis direction. In the combined detection signal, for example, in the frequency band between 1 Hz and 3 kHz, the detection signal from the acceleration sensor (50) in the Z-axis direction is reflected, and in the frequency band above that, the detection signal from the piezoelectric sensor (40) is reflected. As a result, vibrations in the Z-axis direction of the electric motor (15a) can be detected accurately over a relatively wide range of frequencies.

[0099] In step S23, the signal within the carrier frequency band of the inverter (18) is excluded from the detection signal (A value) after step S22 using a digital filter or the like. Here, the carrier frequency corresponds to the frequency that determines the modulation period of the pulse width of the PWM-controlled inverter (18). The user can arbitrarily set the carrier frequency (e.g., 2kHz) in the setting unit (92). This process removes the overtone noise of the inverter (18) carrier that is unnecessary for the detection signal (A value). Alternatively, the carrier signal may be stored without rotating the motor (15a), and the overtone may be calculated from the carrier signal and used.

[0100] In step S24, the calculation unit (91) determines the peak value and effective value (RMS) of the detection signal (B value) in the Z-axis direction after step S23, and stores these in the storage unit (71). In addition to the peak value and effective value in the Z-axis direction, the storage unit (71) may also store each detection signal in the Z-axis direction.

[0101] In step S25, the calculation unit (91) determines a judgment value E in the Z-axis direction. Here, the judgment value E is the value obtained by dividing the peak value of the B value detection signal by the RMS value of the B value detection signal (E = peak value / RMS value). For example, if the bearing of the electric motor (15a) wears out, the absolute value of the judgment value E in the natural vibration value of the electric motor (15a) will increase. Therefore, the judgment value E serves as an indicator for determining whether the electric motor (15a) is faulty.

[0102] In step S25, the determination unit (93) determines whether the determination value E is greater than or equal to a predetermined value. If the determination value E is greater than or equal to a predetermined value in step S25, the process proceeds to step S30. In step S30, the output unit (94) outputs a signal indicating an abnormality. The signal indicating an abnormality is output to the control unit (17) via the communication connector (61). When the control unit (17) receives this signal, the control unit (17) displays on the display unit (19) that the motor (15a) is in an abnormal state. This allows for quick detection of abnormalities such as motor (15a) failure.

[0103] In step S25, if the judgment value E is not equal to or greater than a predetermined value, the process proceeds to step S26. In step S26, the calculation unit (91) determines the peak value and effective value (RMS) of the X-axis detection signal of the acceleration sensor (50) at the same time and stores them in the storage unit (71). The storage unit (71) may also store the X-axis detection signal in addition to the Z-axis peak value and effective value.

[0104] In step S27, the calculation unit (91) determines a judgment value F in the X-axis direction. Here, the judgment value F is the value obtained by dividing the peak value of the detection signal in the X-axis direction by the RMS value of the detection signal in the X-axis direction (F = peak value / RMS value). For example, if the motor (15a) becomes loose due to improper installation of the motor (15a), or if the axis of the motor (15a) and the axis of the fan (15) impeller are misaligned, the judgment value F will increase. Therefore, the judgment value F serves as an indicator for determining whether the motor (15a) is faulty.

[0105] In step S27, the determination unit (93) determines whether the change in the determination value F is greater than or equal to a predetermined value. Here, the change in the determination value F is determined by the difference between the determination value F2 at a certain point in time and the determination value F1 from a predetermined time earlier. The determination value F1 used is the determination value F at the time of the first operation of the electric motor (15a).

[0106] The absolute value of the output of the detection signal in the X-axis direction changes depending on the environment in which the vibration detection device (30) is used. Specifically, this absolute value changes depending on the installation conditions of the air treatment device (10) and the specifications of the vibration damping device (16). Therefore, by using the amount of change in the judgment value F as an indicator, it is possible to predict abnormalities in the electric motor (15a) without being affected by such environmental conditions.

[0107] In step S27, if the change in the determination value F is greater than or equal to a predetermined value, the process proceeds to step S30. In step S30, the output unit (94) outputs a signal indicating an abnormality. In step S28, if the change in the determination value F is not greater than or equal to a predetermined value, the process proceeds to step S28.

[0108] In step S28, the calculation unit (91) determines the peak value and effective value (RMS) of the detection signal in the Y-axis direction of the acceleration sensor (50) at the same time, and stores these in the storage unit (71). In addition to the peak value and effective value in the Y-axis direction, the storage unit (71) may also store the detection signal in the Y-axis direction.

[0109] In step S29, the calculation unit (91) determines a judgment value G in the Y-axis direction. Here, the judgment value G is the value obtained by dividing the peak value of the detection signal in the Y-axis direction by the RMS value of the detection signal in the Y-axis direction (G = peak value / RMS value). For example, if the motor (15a) becomes loose due to improper installation of the motor (15a), or if the axis of the motor (15a) and the axis of the fan (15) impeller are misaligned, the judgment value G will increase. Therefore, the judgment value G serves as an indicator for determining whether the motor (15a) is faulty.

[0110] In step S29, the determination unit (93) determines whether the change in the determination value G is greater than or equal to a predetermined value. Here, the change in the determination value G is determined by the difference between the determination value G2 at a certain point in time and the determination value G1 from a predetermined time earlier. The determination value G1 used is the determination value G at the time of the first operation of the electric motor (15a).

[0111] The absolute value of the output of the detection signal in the Y-axis direction changes depending on the environment in which the vibration detection device (30) is used. Specifically, this absolute value changes depending on the installation conditions of the air treatment device (10) and the specifications of the vibration damping device (16). Therefore, by using the amount of change in the judgment value G as an indicator, it is possible to predict abnormalities in the electric motor (15a) without being affected by such environmental conditions.

[0112] In step S29, if the change in the judgment value G is greater than or equal to a predetermined value, the process proceeds to step S30. In step S30, the output unit (94) outputs a signal indicating an abnormality. In step S30, if the change in the judgment value G is not greater than or equal to a predetermined value, the process returns to step S21.

[0113] (5) Features of the embodiment (5-1) The piezoelectric sensor (40) and the acceleration sensor (50) detect vibrations in the electric motor (15a) at different frequency bands. Therefore, the vibration detection device (30) can cover a wide range of vibration frequency bands in the electric motor (15a) and measure the vibrations of the electric motor (15a) sufficiently.

[0114] (5-2) The piezoelectric sensor (40) and the acceleration sensor (50) are provided on the same module (M). This brings the vibration detection positions of the piezoelectric sensor (40) and the acceleration sensor (50) closer together. More precisely, the piezoelectric sensor (40) and the acceleration sensor (50) have overlapping portions in the thickness direction of the first substrate (31) and the second substrate (32). In other words, the piezoelectric sensor (40) and the acceleration sensor (50) are arranged to overlap in the thickness direction. As a result, the vibration detection positions of the piezoelectric sensor (40) and the acceleration sensor (50) are brought even closer together. Consequently, the measurement accuracy of the vibration of the electric motor (15a) by the vibration detection device (30) can be improved, and abnormalities in the electric motor (15a) can be identified with high accuracy.

[0115] (5-3) A second substrate (32) is stacked on the piezoelectric sensor (40). Therefore, the second substrate (32) can be used as a weight to excite the piezoelectric sensor (40). This improves the accuracy of vibration detection by the piezoelectric sensor (40). Since there is no need to provide a separate weight, the number of parts can be reduced, and the module (M) can be simplified and its reliability improved.

[0116] In addition, the weight of the second substrate (32) as a counterweight can be easily and precisely adjusted by the thickness of the second substrate (32), the material of the second substrate (32), the thickness of the copper foil, the thickness of the plating, and so on.

[0117] (5-4) By mounting the acceleration sensor (50) on the second substrate (32), the acceleration sensor (50) can be used as a weight to excite the piezoelectric sensor (40). This improves the accuracy of vibration detection by the piezoelectric sensor (40). Since there is no need to provide a separate weight, the number of parts can be reduced, and the module (M) can be simplified and its reliability improved.

[0118] Since the acceleration sensor (50) is a semiconductor sensor having a sensor casing (52), the weight of the acceleration sensor (50) that functions as a counterweight can be increased. Since the acceleration sensor (50) is a MEMS type sensor, the accuracy of detecting vibrations of the electric motor (15a) can be improved.

[0119] In addition, the weight of the accelerometer (50) can be easily and precisely adjusted depending on the type (thickness and material) of the sensor casing (52).

[0120] (5-5) The pins (33, 34) that conduct electricity between the second substrate (32) and the first substrate (31) are provided at both ends of the second substrate (32). More precisely, the first pin (33) is provided at one end of the second substrate (32) in the longitudinal direction, and the second pin (34) is provided at the other end of the second substrate (32) in the longitudinal direction. This prevents the deformation of the second substrate (32) in the thickness direction from being hindered by these conductive pins (33, 34). As a result, it is possible to prevent the second substrate (32) from being unable to sufficiently excite the piezoelectric sensor (40).

[0121] (5-6) A piezoelectric sensor (40), an acceleration sensor (50), and an MPU (60) are provided on the same module (M). The detection signals from the piezoelectric sensor (40) and the acceleration sensor (50) are sent to the MPU (60) via energized parts on the circuit board (31,32) without the need for wiring. This suppresses the superposition of external noise on these detection signals and improves the accuracy of detecting vibrations of the electric motor (15a).

[0122] In addition, the first A / D conversion unit (67) of the MPU (60) can convert the detection signal from an analog signal to a digital signal, so the superposition of noise on the detection signal can be suppressed by signal processing of the digital signal.

[0123] (5-7) The piezoelectric sensor (40) detects vibrations of the motor (15a) in the Z-axis direction, and the acceleration sensor (50) detects vibrations of the motor (15a) in the Z-axis, X-axis, and Y-axis directions. Therefore, it is possible to identify not only abnormalities such as bearing wear due to long-term use of the motor (15a), but also abnormalities such as improper mounting of the motor (15a) and misalignment of the shaft.

[0124] (5-8) The MPU (60) subtracts the vibration value of the Z-axis detection signal from the acceleration sensor (50) from the vibration value of the detection signal from the piezoelectric sensor (40). This subtraction also includes adding the two detection signals together after making one of the detection signals out of phase. In this example, this allows the detection signal in frequency band D, where the piezoelectric sensor (40) has excessively high sensitivity, to be removed. As a result, the vibration of the electric motor (15a) can be detected with high accuracy.

[0125] (6) Variant The above-described embodiment may also be configured in the following modified form.

[0126] (6-1) Torture 1 The vibration detection device (30) in Modification 1 differs from the embodiment described above in the configuration of its module (M).

[0127] As shown in Figure 10, in Modification 1, an acceleration sensor (50) is mounted on the upper first surface (S1) of the first substrate (31). A piezoelectric sensor (40) is provided on the lower second surface (S2) of the first substrate (31). The second substrate (32) is provided below the piezoelectric sensor (40). In Modification 1, the first substrate (31), piezoelectric sensor (40), and second substrate (32) are stacked in order from top to bottom. The second substrate (32) is fixed to the electric motor (15a) via a component such as a housing.

[0128] The first electrode (42) of the piezoelectric sensor (40) is in contact with the second copper foil (C2) on the lower second surface (S2) of the first substrate (31). As a result, the second copper foil (C2) functions as the energizing part of the first electrode (42). The second electrode (43) of the piezoelectric sensor (40) is in contact with the fourth copper foil (C4) formed on the upper third surface (S3) of the second substrate (32). As a result, the fourth copper foil (C4) functions as the energizing part of the second electrode (43). The fourth copper foil (C4) conducts to the ground (GND) signal, which is the reference voltage of the first substrate (31), via the first pin (33) and the second pin (34) of the module (M) that corresponds to the reference voltage (0V). As a result, the second electrode (43) can be used as a ground electrode. In addition, the fourth copper foil (C4) functions as a shield to block noise from the piezoelectric sensor (40).

[0129] The first copper foil (C1) on the upper first surface (S1) of the first substrate (31) is electrically connected to ground via the grounding pin among the first pin (33) and second pin (34). As a result, the first copper foil (C1) functions as a shield to block noise from the piezoelectric sensor (40). In this way, the piezoelectric sensor (40) is sandwiched in its thickness direction between the first copper foil (C1) and the fourth copper foil (C4) which function as shields. This effectively blocks the effects of noise on the piezoelectric sensor (40) and improves the detection accuracy of the piezoelectric sensor (40) signal.

[0130] In the first modified example, since the acceleration sensor (50) is not mounted on the second substrate (32), deformation of the second substrate (32) in the thickness direction during manufacturing can be suppressed. As a result, the flatness of the second substrate (32) can be maintained, which prevents the formation of a gap between the first electrode (42) and the second substrate (32) (more precisely, the second copper foil (C2)), and makes it easier to process the second substrate (32).

[0131] In the first modified example, by providing a first substrate (31) above the piezoelectric sensor (40), the first substrate (31) can function as a weight to promote deformation of the piezoelectric film (41). This improves the sensitivity of the piezoelectric film (41) in detecting vibrations in the Z-axis direction.

[0132] (6-2) Modification 2 The vibration detection device (30) of Modified Example 2 has a different circuit configuration from the embodiment described above. The acceleration sensor (50) of Modified Example 2 is configured as an analog output type. The acceleration sensor (50) outputs an analog signal in the Z-axis direction, an analog signal in the X-axis direction, and an analog signal in the Y-axis direction.

[0133] The MPU (60) includes a second A / D converter (72), a third A / D converter (73), and a fourth A / D converter (74). The Z-axis output of the acceleration sensor (50) is connected to the second A / D converter (72) via the second preamplifier (75). The X-axis output of the acceleration sensor (50) is connected to the third A / D converter (73) via the third preamplifier (76). The Y-axis output of the acceleration sensor (50) is connected to the fourth A / D converter (74) via the fourth preamplifier (77). The second A / D converter (72) converts the analog signal in the Z-axis direction into a digital signal and then outputs it to the CPU (66). The third A / D converter (73) converts the analog signal in the X-axis direction into a digital signal and then outputs it to the CPU (66). The fourth A / D converter (74) converts the analog signal in the Y-axis direction into a digital signal and then outputs it to the CPU (66).

[0134] (7) Other embodiments In the embodiments and variations described above, the following configurations may also be used.

[0135] The vibration detection device (30) may detect vibrations of a rotating machine other than the electric motor (15a). The rotating machine may be, for example, a rotary drive device connected to the rotating shaft of the electric motor via a belt. The rotary drive device has a drive shaft driven by a belt and a bearing that rotatably supports the drive shaft. The drive shaft is connected to a rotating body such as a fan.

[0136] The air treatment device (10) may be an air conditioning device that adjusts the temperature of the air in the target space, a humidity control device that adjusts the humidity of the air in the target space, a ventilation device that ventilates the target space, or an air purifier that purifies the air in the target space. The air treatment device (10) may also be an air conditioning device having an indoor unit.

[0137] The electric motor (15a) may also be the driving source for a compressor that compresses the refrigerant.

[0138] The first detection unit (40) is not limited to a piezoelectric sensor (40), but may be an acceleration sensor (50) or another type of vibration sensor. The second detection unit (50) is not limited to an acceleration sensor (50) or a MEMS type sensor, but may be another type of vibration sensor. Other types of vibration sensors include electromagnetic, capacitive, and Doppler types.

[0139] The second detection unit (50) may detect vibrations only in the Z-axis direction, or it may detect vibrations in the Z-axis direction and the X-axis direction, or it may detect vibrations in the Z-axis direction and the Y-axis direction.

[0140] The first substrate (31) and the second substrate (32) may be four-layer substrates. In this case, the inner layers of each substrate (31, 32) may be grounded, thereby shielding the piezoelectric sensor (40).

[0141] The second substrate (32) may be an elastic flexible substrate. This improves the adhesion between the first electrode (42) of the piezoelectric sensor (40) and the metal foil (more precisely, the third copper foil (C3)) of the second substrate (32). In addition, it promotes deformation in the thickness direction of the second substrate (32), which functions as a weight.

[0142] The first detection unit (40) and the second detection unit (50) may not only overlap in the thickness direction of the substrate (31, 32) while being separated from each other, but may also overlap in the thickness direction of the substrate (31, 32) while being in contact with each other.

[0143] The conductive element does not have to be a pin; for example, it may be a conductive element formed on the surface or edge of a substrate such as a BGA (Ball Grid Array), LGA (Land Grid Array), or LCC (Leadless Chip Carrier).

[0144] The processing unit (60) does not have to be an MPU; it may also be a DSP (Digital Signal Processor).

[0145] The memory unit (71) does not have to be located inside the processing unit (60), but may be located separately outside the processing unit (60).

[0146] A transceiver may be used instead of the driver / receiver (65).

[0147] The MPU (60) may perform FFT (Fast Fourier Transform) processing on the detection signal from the piezoelectric sensor (40) and the detection signal from the acceleration sensor (50) before processing in step S21 of Figure 9.

[0148] The vibration detection device (30) may perform the calibration operation described above while the electric motor (15a) is in operation.

[0149] In step S25, the determination unit (93) determines whether the change in the determination value E is greater than or equal to a predetermined value, and the output unit (94) may output a signal indicating an abnormality if this change is greater than or equal to the predetermined value. Here, the change in the determination value E is determined by the difference between the determination value E2 at a certain point in time and the determination value E1 from a predetermined time earlier. The determination value E1 used is the determination value E at the time of the first operation of the electric motor (15a).

[0150] In step S27, the calculation unit (91) determines whether the average value of the detection signals in the X-axis direction is greater than or equal to a predetermined value, and the output unit (94) may output a signal indicating an abnormality if this average value is greater than or equal to the predetermined value. Similarly, in step S29, the calculation unit (91) determines whether the average value of the detection signals in the Y-axis direction is greater than or equal to a predetermined value, and the output unit (94) may output a signal indicating an abnormality if this average value is greater than or equal to the predetermined value.

[0151] The judgment value used in the judgment unit (93) may be determined by learning using AI (Artificial Intelligence).

[0152] Each setting value set in the setting unit (92) may be configured remotely via wireless or wired connection.

[0153] Although embodiments and modifications have been described above, it will be understood that various changes in form and details are possible without departing from the spirit and scope of the claims. Furthermore, elements of the above embodiments, modifications, and other embodiments may be combined or substituted as appropriate.

[0154] The designations "1st," "2nd," "3rd," etc., mentioned above are used to distinguish between the terms to which these designations are attached, and do not limit the number or order of those terms. [Industrial applicability]

[0155] As described above, this disclosure is useful for vibration detection devices, electric motor units, fans, and air treatment devices. [Explanation of symbols]

[0156] 10 Air treatment equipment 15 Fans 15a Rotating machinery (electric motor) 30 Vibration detection device 31 First circuit board 31,32 circuit boards 32 Second board 33. First pin (first energizing component) 34. Second pin (second energizing component) 40 Piezoelectric sensor (first detection unit) 41 Piezoelectric film 42,43 electrode 50. Acceleration sensor (second detection unit) 51 Semiconductors 52 Sensor casing 60 MPU (Processing Unit) 71 Memory section M module U Electric Motor Unit

Claims

1. A first detection unit (40) for detecting vibrations in a first frequency band in a rotating machine (15a), A second detection unit (50) detects vibrations in a second frequency band different from the first frequency band in the rotating machine (15a), A processing unit (60) measures the vibration of the rotating machine (15a) based on the detection signals from the first detection unit (40) and the second detection unit (50), The system comprises a module (M) on which the first detection unit (40) and the second detection unit (50) are provided, The module (M) has substrates (31, 32) on which the first detection unit (40) and the second detection unit (50) are provided. The first detection unit (40) and the second detection unit (50) have portions that overlap each other in the thickness direction of the substrate (31, 32), The first detection unit (40) is a piezoelectric sensor (40), The aforementioned substrates (31, 32) First substrate (31), The piezoelectric sensor (40) includes a second substrate (32) which is stacked in the thickness direction of the first substrate (31) via the piezoelectric sensor (40). Vibration detection device.

2. The piezoelectric sensor (40) comprises a piezoelectric film (41) and electrodes (42, 43) formed on the surface of the piezoelectric film (41). On the side of the second substrate (32) facing the piezoelectric sensor (40), metal foils (C3, C4) that contact the electrodes (42, 43) are formed. The vibration detection device according to claim 1.

3. A first energizing member (33) is connected to the first substrate (31) and one end of the second substrate (32) in the direction along the surface of the first substrate (31), The device comprises the first substrate (31) and a second energizing member (34) connected to the other end of the second substrate (32) in a direction along the surface of the first substrate (31). The vibration detection device according to claim 1 or 2.

4. The second detection unit (50) is a semiconductor sensor (50) having a semiconductor chip (51) and a sensor casing (52) that houses the semiconductor chip (51), The semiconductor sensor (50) is mounted on the second substrate (32). A vibration detection device according to any one of claims 1 to 3.

5. The semiconductor sensor (50) is a MEMS type sensor (50). The vibration detection device according to claim 4.

6. The first detection unit (40) and the second detection unit (50) are mounted on the first substrate (31). A vibration detection device according to any one of claims 1 to 3.

7. The module (M) includes a conversion unit (67, 72, 73, 74) that converts at least one of the detection signals from the first detection unit (40) and the second detection unit (50) from an analog signal to a digital signal. A vibration detection device according to any one of claims 1 to 6.

8. The processing unit (60) is implemented in the module (M) The vibration detection device according to claim 7.

9. The aforementioned processing unit (60) Based on the detection signal from the first detection unit (40) and the detection signal from the second detection unit (50) stored in the memory unit (71), signal processing is performed. Output the signal after signal processing. A vibration detection device according to any one of claims 1 to 8.

10. The first detection unit (40) detects vibrations in the first direction in the rotating machine (15a), The second detection unit (50) is, In the rotating machine (15a), the vibration in the first direction and the vibration in the second direction perpendicular to the first direction are detected, or The rotating machine (15a) detects vibrations in the first direction, vibrations in the second direction, and vibrations in a third direction perpendicular to the first and second directions. A vibration detection device according to any one of claims 1 to 9.

11. The detection signal from the first detection unit (40) and the detection signal from the second detection unit (50) have overlapping frequency bands. The processing unit (60) subtracts the vibration value of the detection signal from the second detection unit (50) from the vibration value of the detection signal from the first detection unit (40), and measures the vibration of the rotating machine (15a) based on the signal after the subtraction. A vibration detection device according to any one of claims 1 to 10.

12. The aforementioned rotating machine is an electric motor (15a), The vibration detection device (30) according to any one of claims 1 to 11 is included. Electric motor unit.

13. An electric motor (15a) having an axis extending in the horizontal direction, The vibration detection device (30) comprises a first detection unit (40) for detecting vibrations in a first frequency band in the electric motor (15a), a second detection unit (50) for detecting vibrations in a second frequency band different from the first frequency band in the electric motor (15a), and a processing unit (60) for measuring the vibration of the electric motor (15a) based on the detection signals from the first detection unit (40) and the second detection unit (50). The first detection unit (40) detects vibrations in the motor (15a) only in the vertical direction, The second detection unit (50) is, In the electric motor (15a), the vertical vibration and the vibration in a second direction perpendicular to the vertical direction are detected, or The motor (15a) detects the vertical vibration, the second vibration, and the third vibration perpendicular to the vertical and second directions. Electric motor unit.

14. A fan comprising the electric motor unit (U) according to claim 12 or 13.

15. An air treatment apparatus comprising the electric motor unit (U) according to claim 12 or 13.

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