Detector and ultrasonic cleaning device

Abstract

Provided is a detection body and an ultrasonic cleaning device that can determine whether the operating state of each component of the ultrasonic cleaning device is normal or abnormal when an abnormality occurs, such as a low output from a sound pressure sensor in the detection body. To this end, the detection body that detects the sound pressure of the cleaning liquid includes a support at least a part of which is immersed in the cleaning liquid, and a plurality of sound pressure sensors that are disposed at equal intervals around the central axis of the support in a non-liquid-contacting portion of the support and have the same detection characteristics, and each of the plurality of sound pressure sensors detects vibrations caused by ultrasonic waves propagated through the support as a sound pressure value.

Description

[Technical field]

[0001] The present invention relates to a sensing element for use in an ultrasonic cleaning device, and to an ultrasonic cleaning device equipped with this sensing element. [Background technology]

[0002] In an ultrasonic cleaning device, a configuration has been proposed in which a detector or sensor capable of detecting sound pressure is arranged to detect the sound pressure of the liquid in a cleaning tank or a processing tank to which ultrasonic waves are applied. For example, the sound pressure detection device described in Patent Document 1 is composed of a probe and a monitor, and the probe includes a rod-shaped sensitive piece, a gripping part for supporting the rear end of the sensitive piece, and a sound pressure sensor bonded to the rear end surface of the sensitive piece inside the gripping part. A piezoelectric element is used as the sound pressure sensor. The adhesive part of the sound pressure sensor and its surrounding part are fixed to the inside of the tip of the gripping part by screwing a holder into the outer peripheral surface of the gripping part so as to cover the rear end of the sensitive piece and the tip of the gripping part from the outside. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2001-21412 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the sound pressure detection device described in Patent Document 1 may have problems such as the sound pressure sensor peeling off or floating from the sensing piece, the holder loosening or breaking, and the sound pressure sensor itself deteriorating when used over a long period of time, and these problems cause problems such as the amplitude of the detection signal becoming smaller than it should be. On the other hand, when the amplitude of the detection signal becomes smaller, there are cases where a problem occurs not only in the sound pressure sensor, but also in the vibrator or oscillator that applies ultrasonic waves to the treatment tank, or where the liquid in the treatment tank has decreased and the tank is in a dry-fire state, making it difficult to determine whether the operating condition of each component is normal or abnormal.

[0005] Therefore, the present invention aims to provide a detector and an ultrasonic cleaning device that can determine whether the operating state of each component of the ultrasonic cleaning device is normal or abnormal when an abnormality occurs, such as a small output from a sound pressure sensor of a detector that detects the sound pressure of the liquid in the cleaning tank of the ultrasonic cleaning device, and can determine whether the operating state of the ultrasonic cleaning device is normal or abnormal based on whether all the operating states of each component are normal or whether there is an abnormality in the operating state of at least one component. Another object of the present invention is to provide a detector and an ultrasonic cleaning device that can determine whether an abnormality has occurred in the sound pressure sensor. Furthermore, the present invention aims to provide a detector and an ultrasonic cleaning device that can determine whether an abnormality has occurred in the sound pressure sensor, the cleaning tank, the vibrator that irradiates ultrasonic waves to the cleaning tank, or the oscillator when an abnormality occurs in the output from the detector. [Means for solving the problem]

[0006] In order to solve the above problems, the detection element of the present invention is an ultrasonic cleaning device equipped with a cleaning tank containing a cleaning liquid, a transducer that irradiates ultrasonic waves into the cleaning tank, and an oscillator that gives a drive signal to the transducer to generate the ultrasonic waves. The detection element detects the sound pressure of the cleaning liquid, and includes a support at least a portion of which is immersed in the cleaning liquid, and a plurality of sound pressure sensors that are disposed at equal intervals around the central axis of the support in a non-liquid-contacting portion of the support and have the same detection characteristics, and each of the plurality of sound pressure sensors detects vibrations caused by the ultrasonic waves propagated through the support as a sound pressure value. It is characterized by:

[0007] The ultrasonic cleaning device of the present invention is an ultrasonic cleaning device comprising: a cleaning tank containing a cleaning liquid; a vibrator that irradiates ultrasonic waves into the cleaning tank; an oscillator that provides a drive signal to the vibrator to generate the ultrasonic waves; a support having at least a tip immersed in the cleaning liquid; and a detector that is arranged at equal intervals around the central axis of the support at the rear end of the support and has a plurality of sound pressure sensors having the same detection characteristics, each of the plurality of sound pressure sensors detecting vibrations caused by the ultrasonic waves propagated through the support as a sound pressure value; and a control means to which the detector is connected, wherein the control means determines whether the operating status of the ultrasonic cleaning device is normal or abnormal based on the detection result of the detector.

[0008] In the ultrasonic cleaning device of the present invention, the control means includes a judgment unit that judges whether the operating state of the detection object is normal or abnormal based on the sound pressure values ​​detected by each of the multiple sound pressure sensors, and a display unit that can display the detection results by the detection object, and the judgment unit sets the multiple sound pressure sensors to one lower sound pressure sensor having the smallest sound pressure value and upper sound pressure sensors excluding the lower sound pressure sensor, and judges whether the operating state of the detection object is normal or abnormal based on the lower sound pressure value detected by the lower sound pressure sensor and a reference sound pressure value corresponding to the upper sound pressure value detected by the upper sound pressure sensor.

[0009] In the ultrasonic cleaning device of the present invention, the judgment unit is characterized in that it judges whether the operating state of the detection object is normal or abnormal based on the comparison result of the product of the reference sound pressure value and a predetermined threshold value and the lower sound pressure value.

[0010] In the ultrasonic cleaning device of the present invention, when the number of the multiple sound pressure sensors is three or more, the reference sound pressure value is the average value of the upper sound pressure values ​​of the top two upper sound pressure sensors having larger sound pressure values ​​among the upper sound pressure sensors.

[0011] In the ultrasonic cleaning device of the present invention, the determination unit determines whether the operating state of the oscillator is normal or abnormal based on the presence or absence of output of the drive signal from the oscillator.

[0012] In the ultrasonic cleaning device of the present invention, the judgment unit judges whether the operating state of the transducer is normal or abnormal based on a comparison result between a predetermined initial sound pressure value and the reference sound pressure value.

[0013] In the ultrasonic cleaning device of the present invention, when the number of the plurality of sound pressure sensors is two, the reference sound pressure value is the upper sound pressure value detected by one of the upper sound pressure sensors.

[0014] The ultrasonic cleaning device of the present invention is characterized in that it further comprises a control device that outputs a stop signal to stop operation of the ultrasonic cleaning device when the judgment unit judges that the operating state of the detection body is abnormal. Effect of the Invention

[0015] According to the present invention, when an abnormality occurs such as a low output from a sound pressure sensor of a detection body that detects the sound pressure of the liquid in the cleaning tank of an ultrasonic cleaning device, it is possible to determine whether the operating status of each component of the ultrasonic cleaning device is normal or abnormal, and it is also possible to determine whether an abnormality has occurred in the sound pressure sensor.Furthermore, when an abnormality occurs in the output from the detection body, it is possible to determine whether an abnormality has occurred in the sound pressure sensor, the cleaning tank, the vibrator that irradiates ultrasonic waves into the cleaning tank, or the oscillator. [Brief description of the drawings]

[0016] [Figure 1] 1(a) and 1(b) are side views showing the configuration of a support body of a sensing element according to a first embodiment, and 1(c) is a plan view of the support body. [Diagram 2] 1A and 1B are side views showing the configuration of a sensing element according to a first embodiment, 1C is a diagram showing a state in which wiring is fixed to the sensing element shown in 1A, and 1D is a plan view of the sensing element. [Diagram 3]1(a) and 1(b) are diagrams showing the configuration of an ultrasonic cleaning device according to a first embodiment, including a block diagram. [Figure 4] 3 is a flowchart showing the procedure of a normality / abnormality determination method according to the first embodiment. [Diagram 5] FIG. 1(a) is a side view showing the configuration of the support body in modified example 1, FIG. 1(b) is a side view showing the configuration of the detection body in modified example 1, FIG. 1(c) is a plan view of the support body shown in (a), and FIG. 1(d) is a plan view of the detection body shown in (b). [Figure 6] FIG. 1(a) is a side view showing the configuration of the support body in Modification Example 2, FIG. 1(b) is a side view showing the configuration of the detection body in Modification Example 2, FIG. 1(c) is a plan view of the support body shown in (a), and FIG. 1(d) is a plan view of the detection body shown in (b). [Figure 7] FIG. 10(a) is a plan view showing the arrangement of the support body and the sound pressure sensor in the third modified example, FIG. 10(b) is a side view showing the configuration of the detection body in the third modified example, FIG. 10(c) is a plan view showing the arrangement of the support body and the sound pressure sensor in the fourth modified example, and FIG. 10(d) is a side view showing the configuration of the detection body in the fourth modified example. [Figure 8] FIG. 10(a) is a plan view showing the arrangement of the support body and the sound pressure sensor in the fifth modified example, FIG. 10(b) is a side view showing the configuration of the detection body in the fifth modified example, FIG. 10(c) is a plan view showing the arrangement of the support body and the sound pressure sensor in the sixth modified example, and FIG. 10(d) is a side view showing the configuration of the detection body in the sixth modified example. [Figure 9] FIG. 13 is a diagram showing a state in which a detection element according to Modification 5 is fixed to a cleaning tank. [Figure 10] 10(a) and 10(b) are diagrams including a block diagram showing the configuration of an ultrasonic cleaning device according to a second embodiment. [Figure 11] 10 is a flowchart showing the procedure of a normality / abnormality determination method according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] First Embodiment A detection element and an ultrasonic cleaning device according to a first embodiment of the present invention will be described in detail with reference to the drawings. 1(a) and (b) are side views showing the configuration of a support 110 of a sensing element 10 according to the first embodiment, and (c) is a plan view of the support 110. Fig. 1(a) is a view seen from direction 1A in (c), and (b) is a view seen from direction 1B in (c). 2(a) and (b) are side views showing the configuration of the sensing body 10 according to the first embodiment, (c) is a diagram showing a state in which wiring has been attached and fixed to the sensing body 10 shown in (a), and (d) is a plan view of the sensing body 10. Fig. 2(a) is a diagram seen from the direction 2A in (c), and (b) is a diagram seen from the direction 2B in (c).

[0018] 3(a) and (b) are diagrams including a block diagram of the configuration of the ultrasonic cleaning device 100 according to the first embodiment.

[0019] As shown in FIG. 3(a), the ultrasonic cleaning device 100 has a configuration including a detection body 10 (FIGS. 2(a), (b), (c)), and as shown in FIG. 3(b), it is also possible to add an external device 60 having a control device 61 to the configuration shown in FIG. 3(a). The configuration of each part will be explained below.

[0020] <Detection object 10> The detection object 10 has a configuration in which three piezoelectric elements as sound pressure sensors are arranged on a support body 110 shown in Figures 1(a), (b), and (c), as shown in Figures 2(a), (b), (c), and (d). The support 110 is a rod-shaped material capable of propagating vibrations based on the sound pressure of the cleaning liquid 23 when immersed in the cleaning tank 20 (FIGS. 3(a) and (b)). Such rod-shaped materials include, for example, those molded from stainless steel or quartz, and the support 110 has a cylindrical shape with a central axis AX1. The change in the sound pressure of the cleaning liquid 23 is caused by ultrasonic waves applied from the transducer 30 (see FIGS. 3(a) and (b)) to the cleaning liquid 23 in the cleaning tank 20, and the vibrations propagated by the support 110 correspond to the sound pressure of the ultrasonic waves applied from the transducer 30.

[0021] As shown in FIGS. 1(a) and 1(b), the support 110 has a front end 110a and a rear end 110b in the Z1-Z2 direction along the central axis AX1. As shown in FIGS. 3(a) and 3(b), the front end 110a side of the support 110 is immersed in the cleaning liquid 23, and the rear end 110b side is disposed above the liquid level 22 of the cleaning liquid 23. In other words, the front end 110a, which is a part of the support 110, is immersed in the cleaning liquid 23. The sound pressure sensors 121, 122, and 123 are disposed at positions higher than the liquid level 22 of the cleaning liquid 23 when the liquid level is at its highest. Therefore, regardless of the change in the liquid level of the cleaning liquid 23, the sound pressure sensors 121, 122, and 123 are disposed at positions that are not immersed in the cleaning liquid 23. In other words, the rear end 110b, which is a non-liquid-contacting part, is always disposed above the liquid level 22 of the cleaning liquid 23. This makes it possible to prevent the sound pressure sensors 121, 122, and 123 from changing in the characteristics, deteriorating, peeling off, and the like, which may be caused by immersion in the cleaning liquid 23 in the cleaning tank 20.

[0022] 1(a), (b), and (c), three inclined surfaces 111, 112, and 113 are formed on the rear end portion 110b of the support 110, symmetrically with respect to the central axis AX1. In other words, these inclined surfaces 111, 112, and 113 are provided at equal angular intervals of 120° with respect to the central axis AX1. These inclined surfaces 111, 112, and 113 have the same or substantially the same planar shape, are provided in the same range in the Z1-Z2 direction, and are inclined so as to approach the central axis AX1 toward the rear end surface 110c, which is the rearmost side of the rear end portion 110b.

[0023] As shown in Fig. 2(a), (b), (c), and (d), three sound pressure sensors 121, 122, and 123 are fixed to the three inclined surfaces 111, 112, and 113, respectively. The fixing is performed using an adhesive, for example, an epoxy adhesive. The sound pressure sensors 121, 122, and 123 are plate-shaped piezoelectric elements having the same shape, the same deformation mode, and the same detection characteristics. The deformation mode is not limited, but for example, when a piezoelectric element having a deformation mode that deforms in the thickness direction is used, its bottom surface is bonded and fixed to the corresponding inclined surface (inclined surfaces 111, 112, and 113). The three sound pressure sensors 121, 122, and 123 are arranged in positions where the corners on the Z2 side (rear end side) are close to the adjacent sound pressure sensors in the Z1-Z2 direction. 2(d), the sound pressure sensors 121, 122, 123 are provided at equal angular intervals of 120° with respect to the central axis AX1. The sound pressure sensors 121, 122, 123 are arranged in positions in which the Z2-side (rear end) corners of the sound pressure sensors are close to the adjacent sound pressure sensors in the Z1-Z2 direction, so that the inclined surfaces 111, 112, 113 on the rear end surface 110c side of the rear end portion 110b of the support 110 are exposed and not covered by the sound pressure sensors 121, 122, 123.

[0024] The sound pressure sensors 121, 122, and 123 are provided on the inclined surfaces 111, 112, and 113, respectively, so that a larger area can be secured for fixing the sound pressure sensors compared to a configuration without inclined surfaces. In addition, both vibration along the central axis AX1 of the support 110 and vibration at an angle to the central axis AX1 can be detected with a certain degree of accuracy. This increases the degree of freedom in selecting a piezoelectric element as a sound pressure detection element. Here, the inclination angles of the inclined surfaces 111, 112, and 113 with respect to the central axis AX1 can be set arbitrarily depending on the size of the sound pressure sensors 121, 122, and 123, etc.

[0025] As shown in Fig. 2(c), Fig. 3(a) and (b), the other ends of signal lines 131, 151, 152 and 153, one end of which is electrically connected to the main body 50 as a control means, are connected to the detection body 10. These signal lines 131, 151, 152 and 153 are made of insulated electric wires. The first signal line 131 is soldered to the support 110, and three connection lines 141, 142 and 143 electrically connected thereto are connected to the negative electrodes of the sound pressure sensors 121, 122 and 123, respectively. Three second signal lines 151, 152 and 153 are connected to the positive electrodes of the sound pressure sensors 121, 122 and 123, respectively. Through this wiring, the pressure applied to each of the sound pressure sensors 121, 122, 123 due to the vibration propagating through the support 110 is converted into a voltage, and this voltage is detected by the main body 50 as the sound pressure value in the cleaning liquid 23 in the cleaning tank 20.

[0026] <Ultrasonic cleaning device 100> As shown in Fig. 3(a), the ultrasonic cleaning device 100 includes a detection object 10, a cleaning tank 20, a vibrator 30, an oscillator 40, and a main body 50. Also, as shown in Fig. 3(b), it is possible to configure the ultrasonic cleaning device 100 with an external device 60 added thereto.

[0027] The cleaning tank 20 is filled with cleaning liquid 23 for cleaning, and the detection body 10 is fixed to the cleaning tank 20 or a fixture (not shown) outside the cleaning tank 20 so that the central axis AX1 of the support 110 is aligned vertically, the front end 110a side is immersed in the cleaning liquid 23, and at least the sound pressure sensors 121, 122, 123 on the rear end 110b side are above the liquid level 22. New cleaning liquid 23 is introduced into the cleaning tank 20 by a pump, solenoid valve, etc. (not shown) at a predetermined amount according to the expected progress of cleaning, and dirty cleaning liquid 23 is discharged to the outside by a pump, solenoid valve, etc. (not shown).

[0028] The inventors have discovered that sound pressure sensors 121, 122, 123 are attached and fixed to the detection body 10, which is a single rod-shaped material, and the same type of signal is generated from each of the sound pressure sensors 121, 122, 123, and by comparing these obtained signals of the same type, when an abnormality occurs in the output from the detection body 10, it is possible to determine in which of the operating states of the sound pressure sensors 121, 122, 123, the cleaning tank 20, the vibrator 30 which irradiates ultrasonic waves to the cleaning tank 20, and the oscillator 40 the abnormality has occurred, and have completed the present invention. In short, the signals generated from the sound pressure sensors 121, 122, and 123 are the same type of signal, and the sound pressure values ​​obtained from the generated signals only provide strong and weak signals, and it is difficult to determine whether the operating conditions of the components of the cleaning device according to the present invention are normal or abnormal by processing them as they are, but the inventors have completed the present invention by comparing the same type of signals, i.e., signals having the same detection characteristics, generated from the sound pressure sensors 121, 122, and 123. Details will be described later. In addition, by attaching and fixing the sound pressure sensors 121, 122, 123 to the rear end 110b side of the detection body 10, which is a single rod-shaped material, the sound pressure sensors 121, 122, 123 are disposed near the rear end 110b side of the detection body 10, which is a single rod-shaped material, thereby eliminating variations in the signals generated by each of the sound pressure sensors 121, 122, 123, and improving the accuracy of the obtained signals.

[0029] A transducer 30 is attached and fixed to the bottom surface 21 of the cleaning tank 20. Any type of transducer 30 can be used depending on the cleaning specifications of the ultrasonic cleaning device 100. The transducer 30 is ultrasonically vibrated by a drive signal provided from an oscillator 40. The ultrasonic waves are irradiated into the cleaning tank 20 and applied to the cleaning liquid 23 in the cleaning tank 20. The sound pressure in the cleaning liquid 23 varies in accordance with the ultrasonic vibration.

[0030] The main body 50 includes a calculation unit 51, a storage unit 52, a determination unit 53, a display unit 54, an input unit 55, and a control device 61. The calculation unit 51 calculates the sound pressure values ​​detected by the sound pressure sensors 121, 122, and 123 based on the voltages between the first signal line 131 and each of the three second signal lines 151, 152, and 153. These sound pressure values ​​are calculated by displaying voltage values ​​stored in advance in the storage unit 52 as the intensity of sound pressure. Here, the storage unit 52 stores a conversion table and a conversion formula based on the correlation between the voltage value and the sound pressure value, and the calculation unit 51 calculates the sound pressure value from the voltage value based on the conversion table and the conversion formula.

[0031] The calculation unit 51 associates the calculated sound pressure value with the name of the corresponding sound pressure sensor (sound pressure sensors 121, 122, 123) and stores it in the storage unit 52. Furthermore, the calculation unit 51 calculates the average value Ave (reference sound pressure value) of the top two sound pressure values, i.e., the two larger sound pressure values ​​(upper sound pressure values), among the sound pressure values ​​detected by the three sound pressure sensors 121, 122, 123, and stores it in the storage unit 52 in association with the names of the two sound pressure sensors (upper sound pressure sensors) that detected these sound pressure values. In addition, the calculation unit 51 combines the lowest sound pressure value Min, i.e., the smallest sound pressure value (lower sound pressure value), with the name of the sound pressure sensor (lower sound pressure sensor) that detected this sound pressure value and stores it in the storage unit 52. Here, the upper sound pressure sensors are the two sound pressure sensors among the three sound pressure sensors 121, 122, 123 excluding the lower sound pressure sensor.

[0032] The sound pressure value calculated by the calculation unit 51 is output to the judgment unit 53, and the judgment unit 53 performs a comparison calculation between the product of the average value Ave and a predetermined threshold value X and the lowest sound pressure value Min, and judges whether the operation state of the sound pressure sensors 121, 122, and 123 is normal or abnormal, that is, judges whether an abnormality has occurred in the operation state, based on the comparison result. The judgment result is stored in the memory unit 52 and is displayed on the display unit 54 in a predetermined format in the process shown in FIG. 4. The threshold value X is input in advance by operating the input unit 55 and is stored in the memory unit 52. The main body unit 50 (judgment unit 53) as a control means judges that the operation state of the ultrasonic cleaning device 100 is normal when the operation states of all the sound pressure sensors 121, 122, and 123 are normal, and judges that the operation state of the ultrasonic cleaning device 100 is abnormal when any of the operation states is abnormal.

[0033] The control device 61 receives the determination result by the determination unit 53, generates a control signal for the oscillator 40 based on this determination result, and outputs it to the oscillator 40. An example of this control signal is a control signal for causing the oscillator 40 to stop sending a drive signal to the vibrator 30 when the determination result by the determination unit 53 determines that an abnormality has occurred in the operating state of any of the sound pressure sensors 121, 122, and 123.

[0034] As shown in Fig. 3(b), the external device 60 includes a control device 61 connected to the main body 50 and the oscillator 40 of the ultrasonic cleaning device 100. The control device 61 has the same functions as the control device 61 provided in the main body 50 in the configuration shown in Fig. 3(a).

[0035] 4 is a flow chart showing a procedure for determining whether the operating state of the ultrasonic cleaning device according to the first embodiment is normal or abnormal, i.e., determining whether the operating state of each component is normal or abnormal. Hereinafter, normal / abnormal determination in the first embodiment will be described with reference to FIG. 4.

[0036] Before starting to drive the transducer 30, the input unit 55 is operated to set the threshold value X in advance and store it in the memory unit 52 (step S11 in FIG. 4). The threshold value X is set arbitrarily depending on the characteristics (such as frequency) of the ultrasonic waves generated by the transducer 30, the temperature, liquid depth, and amount of the cleaning liquid 23, the arrangement height of the sound pressure sensors 121, 122, and 123 in the cleaning tank 20, the characteristics of the sound pressure sensors 121, 122, and 123, the vibration characteristics of the support 110, the arrangement of the detection object 10 in the cleaning tank 20, the shape and type of the object to be cleaned, and the like. The threshold value X is set to prevent erroneous detection due to the sound pressure value of the cleaning tank 20 or the like, which constantly varies depending on the environment, etc.

[0037] Next, the oscillator 40 starts to output a drive signal to the transducer 30, and the transducer 30 irradiates ultrasonic waves to the cleaning tank 20. At this time, sound pressure corresponding to the irradiated ultrasonic waves is generated in the cleaning liquid 23 in the cleaning tank 20. In the support 110 of the detection object 10, vibrations corresponding to this sound pressure are generated in the part immersed in the cleaning liquid 23, and these vibrations are propagated toward the rear end 110b. The vibrations are converted into voltages proportional to deformations in the sound pressure sensors 121, 122, and 123 provided on the inclined surfaces 111, 112, and 113 of the rear end 110b, and the voltages are converted into sound pressure values ​​in the calculation unit 51, whereby the sound pressure values ​​in the sound pressure sensors 121, 122, and 123 are detected (step S12). The detected sound pressure values ​​are stored in the storage unit 52 in association with the names of the sound pressure sensors 121, 122, and 123.

[0038] The calculation unit 51 compares the three sound pressure values ​​detected by the three sound pressure sensors 121, 122, 123 at the same timing, and determines the order based on the magnitude of the sound pressure values. Furthermore, the calculation unit 51 calculates the average value Ave of the top two sound pressure values, and stores it in the storage unit 52 together with the name identifying the corresponding sound pressure sensor (step S13). The calculation unit 51 also stores the lowest sound pressure value Min in the storage unit 52 together with the name identifying the corresponding sound pressure sensor (step S14). In the storage operations in the above steps S13 and S14, the time at that time is also associated and stored.

[0039] The lowest sound pressure value Min may be stored when determining the ranking. Furthermore, if the sound pressure values ​​of the three sound pressure sensors 121, 122, and 123 are identical to each other, any two are taken as the top two sound pressure values ​​to calculate the average value Ave (step S13), and the remaining one is stored in the memory unit 52 as the lowest sound pressure value Min (step S14).

[0040] The average value Ave and the lowest sound pressure value Min are given to the determination unit 53, which reads out the threshold value X from the storage unit 52, calculates the product of the average value Ave and the threshold value X, and compares it with the sound pressure value Min (step S15).

[0041] If the sound pressure value Min is greater than the product of the average value Ave and the threshold value X (YES in step S15), the determination unit 53 determines that the operating state of the sound pressure sensor corresponding to the sound pressure value Min is normal (step S16). At this time, the main body 50 as a control means determines that the operating state of the ultrasonic cleaning device 100 is normal.

[0042] On the other hand, if the sound pressure value Min is equal to or smaller than the product of the average value Ave and the threshold value X (NO in step S15), the operating state of the sound pressure sensor corresponding to the sound pressure value Min is determined to be abnormal. When it is determined to be abnormal, the determination unit 53 causes the display unit 54 to display that there is an abnormality in the operating state of the sound pressure sensor (step S17). Thereafter, regardless of the presence or absence of an abnormality, the determination unit 53 causes the display unit 54 to display the average value Ave as the sound pressure value following steps S16 and S17 (step S18). At this time, the main body unit 50 as a control means determines that the operating state of the ultrasonic cleaning device 100 is abnormal.

[0043] When the threshold value X is used to determine whether the sound pressure value Min is greater than the product of the average value Ave and the threshold value X, as in step X15 above, it is preferable to set a value greater than 0 and less than 1. Here, by increasing the threshold value X (for example, by setting it to 0.7 or more), an abnormality in the operating state of the sound pressure sensor can be determined early, thereby preventing the occurrence of effects on the object to be cleaned due to peeling, etc. By decreasing the threshold value X (for example, by setting it to 0.5 or less), it is possible to prevent a change in the sound pressure value due to the cleaning conditions, etc. from being confused with an abnormality in the operating state of the sound pressure sensor and determining it to be abnormal.

[0044] As described above, the average of the top two sound pressure values ​​is calculated and the operating state is judged to be normal or abnormal based on this. Since the sound pressure value of the sound pressure sensor judged to be abnormal is a significantly low value, and it is considered extremely unlikely that two or more sound pressure sensors out of the three sound pressure sensors 121, 122, and 123 will fail at the same time, the average of the top two is used as the judgment standard. This improves the detection accuracy according to the present invention.

[0045] Regarding judging whether the sound pressure sensor is operating normally or abnormally based on the product of the average Ave sound pressure value of the upper sound pressure sensor and the threshold value X, rather than on the sound pressure value itself, the detected sound pressure value fluctuates because the cleaning liquid 23 flows in and out of the cleaning tank 20 and the vibration propagation state is constantly changing due to changes corresponding to the environment, such as the shaking of the liquid surface. Therefore, if the sound pressure sensor is judged to be operating normally or abnormally based on the sound pressure value itself, there is a risk of false detection due to a slight fluctuation in the sound pressure value. In contrast, using the product with the threshold value X makes it possible to prevent false detection due to minute fluctuations, and also makes it easier to judge the operating state of a sound pressure sensor with a significantly reduced sound pressure value as abnormal.

[0046] Modifications will be described below. The shape of the support used for the detection element may be any shape as long as a certain area, i.e., a part of the support is immersed in the cleaning liquid 23 in the cleaning tank 20 and the sound pressure sensor is disposed in a non-liquid-contacting portion. For example, a cylindrical shape without an inclined surface as shown in Fig. 5(a), a prismatic shape as shown in Fig. 6(a), a cylindrical shape as shown in Fig. 7, and a cylindrical shape with a flange as shown in Fig. 8 can be mentioned.

[0047] (Variation 1) 5(a) is a side view showing the configuration of support 210 in Modification 1, (b) is a side view showing the configuration of the sensing element in Modification 1, (c) is a plan view of support 210 shown in (a), and (d) is a plan view of the sensing element shown in (b). Fig. 5(b) is a view seen from the 5B direction of (d).

[0048] 5(a) includes a front end 210a and a rear end 210b in the Z1-Z2 direction along the central axis AX2. Sound pressure sensors 221, 222, and 223 having the same configuration as the sound pressure sensors 121, 122, and 123 of the first embodiment are adhesively fixed to the support 210 on an outer circumferential surface 211 of the rear end 210b at equal angular intervals with respect to the central axis AX2.

[0049] (Variation 2) 6(a) is a side view showing the configuration of support 310 in Modification 2, (b) is a side view showing the configuration of the detection element in Modification 2, (c) is a plan view of support 310 shown in (a), and (d) is a plan view of the detection element shown in (b). Fig. 6(a) is a view seen from direction 6A in (c), and (b) is a view seen from direction 6B in (d).

[0050] 6(a) has a rectangular prism shape including a front end 310a and a rear end 310b in the Z1-Z2 direction along the central axis AX3, and four outer surfaces 311, 312, 313, 314. Four sound pressure sensors 321, 322, 323, 324 having the same configuration as the sound pressure sensors 121, 122, 123 of the first embodiment are adhesively fixed to the support 310 on the four outer surfaces 311, 312, 313, 314 of the rear end 310b, respectively. The sound pressure sensors 321, 322, 323, 324 have a width smaller than the outer surfaces 311, 312, 313, 314, and therefore can be fixed to the support 310 without contacting each other.

[0051] (Variations 3 and 4) Fig. 7(a) is a plan view showing the arrangement of the support 410 and sound pressure sensors 421, 422, 423 in Modification 3, and Fig. 7(b) is a side view showing the configuration of the detection element according to Modification 3. Fig. 7(c) is a plan view showing the arrangement of the support 410 and sound pressure sensors 451, 452, 453 in Modification 4, and Fig. 7(d) is a side view showing the configuration of the detection element according to Modification 4. Figs. 7(a) and (c) show a state in which the support 410 is closed by the lid 413, and the internal structure is shown by dashed lines. In Modifications 3 and 4, common members will be described with the same reference numerals.

[0052] The support 410 is a hollow, bottomed, cylindrical member, and is made of the same material as in the first embodiment. 7(a) and (b), three sound pressure sensors 421, 422, and 423 are adhesively fixed onto a bottom surface 411 inside a support 410. These sound pressure sensors 421, 422, and 423 are arranged symmetrically with respect to a central axis AX4 of the support 410 at equal angular intervals, in other words, arranged at equal intervals around the central axis AX4 and extending radially from the central axis AX4 side.

[0053] After the sound pressure sensors 421, 422, and 423 are disposed inside the support 410, the upper part of the support 410 is sealed with a disk-shaped lid 413, which makes it possible to prevent liquid from entering the internal space in which the sound pressure sensors are disposed.

[0054] A connector 430 is disposed on the lid portion 413 and is electrically connected to each of the sound pressure sensors 421, 422, and 423. A cable 440 connected to the main body portion 50 is connected to the connector 430, thereby connecting the sound pressure sensors 421, 422, and 423 and the main body portion 50 to each other.

[0055] 7(c) and (d), three sound pressure sensors 451, 452, and 453 are adhesively fixed onto an inner peripheral surface 412 of a support 410. These sound pressure sensors 451, 452, and 453 are arranged symmetrically with respect to a central axis AX4 of the support 410 at equal angular intervals, in other words, arranged at equal intervals around the central axis AX4 and arranged to extend along the central axis AX4. The configurations of the lid 413, the connector 430, and the cable 440 are the same as those of the third modification.

[0056] In support 410, a bottom wall having bottom surface 411 and a side wall having inner peripheral surface 412 are preferably formed with thicknesses taking into consideration ultrasonic wave transmission and transparency, durability, and liquid-tightness.

[0057] With the configurations of Modifications 3 and 4, when the support 410 is immersed in the cleaning liquid 23, the internal space functions as a non-liquid-contacting portion into which the cleaning liquid 23 does not penetrate. This makes it possible to realize a sensing element that is compact and easily manufactured, and has a form that reliably ensures liquid-tightness.

[0058] (Variations 5 and 6) FIG. 8(a) is a plan view showing the arrangement of the support 510 and the sound pressure sensors 521, 522, and 523 in the fifth modification, and FIG. 8(b) is a side view showing the configuration of the detection body according to the fifth modification. FIG. 8(c) is a plan view showing the arrangement of the support 510 and the sound pressure sensors 551, 552, and 553 in the sixth modification, and FIG. 8(d) is a side view showing the configuration of the detection body according to the sixth modification. FIG. 9 is a cross-sectional view of the cleaning tank 20 showing the state in which the detection body according to the fifth modification is fixed to the cleaning tank 20. FIGS. 8(a) and 8(c) show the state in which the support 510 is closed by the lid 513, and the internal structure is shown by the broken line. In the fifth modification and the sixth modification, the same reference numerals are used to describe the common members.

[0059] The support body 510 is made of the same material as in the first embodiment, and has a configuration in which a hollow, cylindrical main body portion 514 and a disk portion 515 having a disk shape with a larger diameter than the main body portion 514 and closing the bottom of the main body portion 514 are integrally formed. The main body portion 514 and the disk portion 515 have a common central axis AX5. The outer periphery of the disk portion 515 extends in a flange-like shape in the radial direction outward beyond the outer periphery of the main body portion 514.

[0060] 8(a) and 8(b), three sound pressure sensors 521, 522, and 523 are adhesively fixed onto a bottom surface 511 inside a support 510. These sound pressure sensors 521, 522, and 523 are arranged to extend radially from the central axis AX5 side so as to be symmetrical to one another at equal angular intervals with respect to the central axis AX5 of the support 510.

[0061] After the sound pressure sensors 521, 522, and 523 are disposed inside the support 510, the upper part is sealed with a disk-shaped lid 513, which makes it possible to prevent liquid from entering the internal space in which the sound pressure sensors are disposed.

[0062] A connector 530 is disposed on the lid 513 and is electrically connected to each of the sound pressure sensors 521, 522, and 523. A cable 540 connected to the main body 50 is connected to the connector 530, thereby connecting the sound pressure sensors 521, 522, and 523 to the main body 50. The connector 530 and the cable 540 are disposed concentrically with the central axis AX5, and are provided in a range smaller than the support 510 in the radial direction.

[0063] 8(c) and (d), three sound pressure sensors 551, 552, and 553 are adhesively fixed onto an inner peripheral surface 512 of a support 510. These sound pressure sensors 551, 552, and 553 are arranged to extend along a central axis AX5 at positions symmetrical to one another at equal angular intervals about the central axis AX5 of the support 510. The configurations of the lid 513, the connector 530, and the cable 540 are the same as those of the fifth modification.

[0064] In support 510, disk portion 515 having bottom surface 511 and side wall having inner peripheral surface 512 are preferably formed with thicknesses taking into consideration ultrasonic wave transmission and transparency, durability, and liquid-tightness.

[0065] A spiral groove is formed on the outer peripheral surface 514a of the main body 514 of the support 510. A ring-shaped nut 516 having a spiral groove on its inner peripheral surface is screwed onto this outer peripheral surface 514a. This nut 516 is movable in a direction along the central axis AX5 of the support 510 as the spiral groove on its inner peripheral surface meshes with the spiral groove on the outer peripheral surface 514a of the main body 514.

[0066] As shown in FIG. 9, the side wall 24 of the cleaning tank 20 is provided with a fixing hole 25 formed in a circular shape having the same diameter as the main body 514 of the support 510. The detection body according to the fifth modification is inserted into the fixing hole 25 from inside the cleaning tank 20, and the cable 540, the connector 530, and the lid 513 side of the main body 514 are exposed to the outside of the cleaning tank 20. In this state, the nut 516 is screwed onto the main body 514 on the outside of the cleaning tank 20, and the side wall 24 of the cleaning tank 20 is sandwiched between the nut 516 and the disk part 515, and the sandwiched part is fixed with an adhesive. As a result, with the disk part 515 disposed inside the cleaning tank 20, it is possible to seal the fixing hole 25 so as to prevent the cleaning liquid 23 from entering or exiting the fixing hole 25. Such arrangement of the sensing elements can also be performed for the sensing elements of Modification 6 in the same manner.

[0067] The configurations of Modifications 5 and 6 allow the disk portion 515 of the support 510 to be immersed in the cleaning liquid 23 in the cleaning tank 20 with a compact configuration, and can be reliably fixed to the cleaning tank 20. Furthermore, when the disk portion 515 is immersed in the cleaning liquid 23, the internal space of the support 510 functions as a non-liquid-contact portion into which the cleaning liquid 23 does not penetrate. This allows the detection element to be realized in a form that reliably ensures liquid-tightness with a compact, easily manufactured configuration.

[0068] In the above first embodiment and modified examples 1, 3, 4, 5, and 6, a configuration having three sound pressure sensors has been described, and in modified example 2, a configuration having four sound pressure sensors has been described, but the number of sound pressure sensors is not limited to these, and two or five or more may be arranged at equal angular intervals. When there are two sound pressure sensors, the sound pressure value of one upper sound pressure sensor is used as the reference sound pressure value instead of the average value Ave of the sound pressure values ​​of the two upper sound pressure sensors in the above first embodiment. When there are four or more sound pressure sensors, it is preferable to use the average value Ave of the sound pressure values ​​of the two upper sound pressure sensors as in the above first embodiment, but all sound pressure sensors except one lower sound pressure sensor, or three or more sound pressure sensors, may be set as the upper sound pressure sensor, and the average value of their sound pressure values ​​may be used as the reference sound pressure value.

[0069] In the first embodiment described above, in order to determine whether the operating state of the sound pressure sensor is normal or abnormal, the product of the average sound pressure value Ave of the upper sound pressure sensor and the threshold value X is compared with the lowest sound pressure value Min. However, the comparison target with the sound pressure value Min is not limited to this, and for example, a value obtained by adding or subtracting a threshold value instead of the threshold value X to or from the average sound pressure Ave may be used.

[0070] In the first embodiment, a piezoelectric element is used as the sound pressure sensor, but the present invention is not limited to this as long as it can detect the sound pressure of the cleaning liquid 23 in the cleaning tank 20. For example, a diaphragm (vibration plate) may also be used.

[0071] In the first embodiment, adjacent sound pressure sensors are arranged close to each other. This close distance is set by the size of the piezoelectric element as the sound pressure sensor and the radial size of the support 110, and by arranging them close to each other in this manner, it is possible to suppress the variation in the sound pressure values ​​detected by each sound pressure sensor to a certain value or less. In terms of the effect of suppressing such variation, it is preferable that the minimum distance between adjacent sound pressure sensors is greater than 0 and is equal to or less than 50% of the width of the sound pressure sensor.

[0072] In the above first embodiment, the detection body 10 was positioned so that the sound pressure sensors 121, 122, and 123 were exposed from the cleaning liquid 23, but if a cover or the like is provided to cover the rear end portion 110b of the support body 110 in a watertight manner so as not to hinder deformation of the sound pressure sensors 121, 122, and 123, the sound pressure sensors 121, 122, and 123 may also be positioned below the water surface of the cleaning liquid 23.

[0073] (Examples 1 and 2) Tables 1 and 2 show numerical examples 1 and 2 of the detection results in the ultrasonic cleaning device 100 according to the first embodiment, respectively.

[0074] [Table 1]

[0075] [Table 2]

[0076] In Example 1 shown in Table 1, the sound pressure value A detected by the sound pressure sensor 121 is 51 (unit: mV), the sound pressure value B detected by the sound pressure sensor 122 is 48 (unit: mV), and the sound pressure value C detected by the sound pressure sensor 123 is 53 (unit: mV). From these sound pressure values, the average value Ave of the sound pressure values ​​of the two sound pressure sensors 121 and 123, which are the upper sound pressure sensors, is 52 (unit: mV). On the other hand, the sound pressure value 48 of the sound pressure sensor 122, which is the lower sound pressure sensor, is the lowest sound pressure value Min. When the threshold value X is set to 0.5, the average value Ave×X is 26, so this sound pressure value 26 is compared with 48 as the sound pressure value Min, and since 48 is larger, the operating state of the sound pressure sensor 122, which is the lower sound pressure sensor, is determined to be normal.

[0077] In Example 2 shown in Table 2, the sound pressure value A detected by the sound pressure sensor 121 is 51 (unit: mV), the sound pressure value B detected by the sound pressure sensor 122 is 15 (unit: mV), and the sound pressure value C detected by the sound pressure sensor 123 is 53 (unit: mV). From these sound pressure values, the average value Ave of the sound pressure values ​​of the two sound pressure sensors 121 and 123, which are the upper sound pressure sensors, is 52 (unit: mV). On the other hand, the sound pressure value 15 of the sound pressure sensor 122, which is the lower sound pressure sensor, is the lowest sound pressure value Min. When the threshold value X is set to 0.5, the average value Ave×X is 26, so this sound pressure value 26 is compared with 15 as the sound pressure value Min, and since 15 is smaller, it is determined that the operating state of the sound pressure sensor 122, which is the lower sound pressure sensor, is abnormal, and the fact that the operating state is abnormal is displayed on the display unit 54.

[0078] According to the above first embodiment, when an abnormality occurs in the operating condition, such as a small output from the sound pressure sensors 121, 122, 123 that detect the sound pressure of the cleaning liquid 23 in the cleaning tank 20 of the ultrasonic cleaning device 100, it is possible to quickly and simply determine which of the sound pressure sensors 121, 122, 123 has an abnormality.

[0079] <Second embodiment> Next, a second embodiment of the present invention will be described. Figures 10(a) and 10(b) are diagrams showing the configuration of an ultrasonic cleaning device 600 according to the second embodiment, including a block diagram. As shown in Figure 10(a), in the ultrasonic cleaning device 600 of the second embodiment, in addition to the same configuration as the ultrasonic cleaning device 100 of the first embodiment, a signal that is the same as the drive signal given from the oscillator 40 to the transducer 30 is also output to the main body 50 at the same time. Also, as shown in Figure 10(b), the ultrasonic cleaning device 600 can be configured to include an external device 60 having a control device 61 similar to that of the first embodiment.

[0080] In the ultrasonic cleaning device 600, the oscillator 40 is configured to simultaneously send the same drive signal to the transducer 30 and the main body 50. In the main body 50, the determination unit 53 identifies whether or not a drive signal has been received from the oscillator 40, and determines whether or not the oscillator 40 is correctly outputting the drive signal based on the identification result. The main body 50 (determination unit 53) as a control means determines that the operating state of the ultrasonic cleaning device 600 is normal when all of the operating states of the sound pressure sensors 121, 122, and 123, the operating state of the transducer 30, and the operating state of the oscillator 40 are normal, and determines that the operating state of the ultrasonic cleaning device 600 is abnormal when there is an abnormality in the operating state of any of the components.

[0081] 11 is a flowchart showing the procedure of normal / abnormal determination according to the second embodiment. Hereinafter, the flow of normal / abnormal determination in the second embodiment will be described with reference to FIG.

[0082] Before starting to drive the transducer 30, the input unit 55 is operated to set the thresholds X, Y and the initial sound pressure value I in advance and store them in the storage unit 52 (step S21 in FIG. 11). The thresholds X and Y are set in the same manner as the threshold X in the first embodiment, and may be set to the same numerical value. The initial sound pressure value I is a sound pressure value estimated to be detected when the sound pressure sensors 121, 122, 123 normally detect ultrasonic waves generated by a drive signal provided from an oscillator 40 in a normal operating state to a transducer 30 in a normal operating state. Alternatively, it may be a sound pressure value when detection is actually performed by a sound pressure sensor known to be in a normal operating state.

[0083] Next, output of a drive signal from the oscillator 40 to the transducer 30 and the main body 50 is started, and the determination unit 53 determines whether or not a predetermined drive signal has been received from the oscillator 40 (step S22).

[0084] In determining whether or not a predetermined drive signal has been received from oscillator 40 (step S22), if the drive signal has been received (YES in step S22), it is determined that oscillator 40 is operating normally (step S23), and if the drive signal has not been received (NO in step S22), judgment unit 53 determines that there is an abnormality in the operating state of oscillator 40 (step S34).

[0085] When a predetermined drive signal is received from the oscillator 40 to the main body 50 (YES in step S22), the drive signal is also input to the transducer 30, and ultrasonic waves generated by the transducer 30 are irradiated to the cleaning tank 20. At this time, sound pressure corresponding to the irradiated ultrasonic waves is generated in the cleaning liquid 23 in the cleaning tank 20. In the support 110 of the detection body 10, vibrations corresponding to this sound pressure are generated in the part immersed in the cleaning liquid 23, and these vibrations are propagated to the rear end 110b side. The vibrations are converted into voltages proportional to deformations by the sound pressure sensors 121, 122, and 123 provided on the inclined surfaces 111, 112, and 113 of the rear end 110b, and the voltages are converted into sound pressure values ​​by the calculation unit 51, whereby the sound pressure values ​​at the sound pressure sensors 121, 122, and 123 are detected (step S24). The detected sound pressure values ​​are stored in the storage unit 52 in association with the sound pressure sensors 121, 122, and 123.

[0086] The calculation unit 51 compares the three sound pressure values ​​detected by the three sound pressure sensors 121, 122, and 123 at the same timing, and determines the order according to the magnitude of the sound pressure values. Furthermore, the calculation unit 51 calculates the average value Ave (reference sound pressure value) of the top two sound pressure values ​​(upper sound pressure values), and stores it in the storage unit 52 together with the name identifying the corresponding sound pressure sensor (step S25). The calculation unit 51 also stores the lowest sound pressure value Min (lower sound pressure value) in the storage unit 52 together with the name identifying the corresponding sound pressure sensor (step S26). In the storage operations in the above steps S25 and S26, the time at that time is also associated and stored.

[0087] Next, the average value Ave and the lowest sound pressure value Min are provided to the determination unit 53, which reads out the threshold value X from the storage unit 52, calculates the product of the average value Ave and the threshold value X, and compares it with the sound pressure value Min (step S27).

[0088] If the sound pressure value Min is greater than the product of the average value Ave and the threshold value X (YES in step S27), the determination unit 53 determines that the sound pressure sensor corresponding to the sound pressure value Min is in a normal operating state (step S28). On the other hand, if the sound pressure value Min is less than or equal to the product of the average value Ave and the threshold value X (NO in step S27), the determination unit 53 determines that the operating state of the sound pressure sensor corresponding to the sound pressure value Min is abnormal. When determining that the operating state is abnormal, the determination unit 53 causes the display unit 54 to display that there is an abnormality in the operating state of the sound pressure sensor (step S29).

[0089] Regardless of whether or not there is an abnormality in the operating state of the sound pressure sensor, following steps S28 and S29, the determination unit 53 reads out the threshold value Y and the initial sound pressure value I from the storage unit 52, and compares their product with the average value Ave (step S30).

[0090] If the average value Ave is greater than the product of the threshold value Y and the initial sound pressure value I (YES in step S30), the determination unit 53 determines that the transducer 30 is in a normal operating state (step S31) and causes the display unit 54 to display the average value Ave as a sound pressure value (step S32). At this time, the main body unit 50 (determination unit 53) as a control means determines that the operating state of the ultrasonic cleaning device 600 is normal, since the operating states of all of the components are normal.

[0091] On the other hand, if the average value Ave is smaller than or equal to the product of the threshold value Y and the initial sound pressure value I (NO in step S30), the determination unit 53 determines that the operating state of the transducer 30 is abnormal or dry-burning (step S33).

[0092] After determining in step S33 that the operating state of the vibrator 30 is abnormal, and after determining in step S34 that the operating state of the oscillator 40 is abnormal, the determination unit 53 sends an error signal to the control device 61 (step S35). The control device 61, which has received the error signal, sends a stop signal to the oscillator 40 to stop sending the drive signal to the vibrator 30 (step S36). Here, the main body 50 as a control means determines that the operating state of the ultrasonic cleaning device 600 is abnormal when the operating state of any of the components is abnormal.

[0093] The threshold value Y is set based on the fluctuation of the sound pressure value due to the environment, etc., and the allowable range of deterioration in the performance of the sound pressure sensor. When the threshold value Y is used to determine whether the average value Ave is greater than the product of the initial sound pressure value I and the threshold value Y, as in step S30 above, it is preferable to set a value greater than or equal to 0.5 and less than 1. By setting the threshold value Y to 0.5 or more, the operating state of the vibrator 30 is not determined to be abnormal due to a slight change in the average value Ave, which changes depending on the actual cleaning situation, and cleaning can be continued stably, but since the threshold value changes depending on the usage situation, it is preferable to set it according to the usage environment.

[0094] Example 3 Table 3 shows examples of numerical values ​​of the detection results in the ultrasonic cleaning device 600 according to the second embodiment.

[0095] [Table 3]

[0096] In Example 3 shown in Table 3, the initial sound pressure value I is 55 (unit: mV), the sound pressure value A detected by the sound pressure sensor 121 is 21 (unit: mV), the sound pressure value B detected by the sound pressure sensor 122 is 21 (unit: mV), and the sound pressure value C detected by the sound pressure sensor 123 is 19 (unit: mV). From these sound pressure values, the average value Ave of the sound pressure values ​​of the two sound pressure sensors 121 and 122, which are the upper sound pressure sensors, is 21 (unit: mV). On the other hand, the sound pressure value 19 of the sound pressure sensor 123, which is the lower sound pressure sensor, is the lowest sound pressure value Min. Then, when the threshold value X is 0.5 and the threshold value Y is 0.6, the average value Ave×X is 10.5, and the initial sound pressure value I×threshold value Y is 33.

[0097] In such a situation, on the condition that there is a signal from the oscillator 40 (Yes in step S22 of FIG. 11, the operating state of the oscillator 40 is normal), the determination results in steps S27 and S30 are as follows. (1) Regarding step S27 "Min>Ave×X?", since the sound pressure value Min is 19 and Ave×X is 10.5, the sound pressure value Min is greater and the operating condition of the sound pressure sensor is determined to be normal. (2) Regarding step S30 "Ave>I×Y?", since the average value Ave is 21 and I×Y is 33, it is determined that there is an abnormality in the operating condition of the vibrator 30 since the average value Ave is smaller.

[0098] According to the second embodiment, in addition to the advantageous effects of the first embodiment, when an abnormality occurs in the output from the detection object 10, it becomes possible to determine which of the sound pressure sensors 121, 122, 123, the vibrator 30, and the oscillator 40 has experienced the abnormality in its operating state. Other functions, effects, and modifications are similar to those of the first embodiment. Although the present invention has been described with reference to the above-mentioned embodiment, the present invention is not limited to the above-mentioned embodiment, and improvements or modifications can be made within the scope of the invention or the purpose of the improvements. [Explanation of symbols]

[0099] 10 Detection object 20 Cleaning tank 21 Bottom 22 Liquid level 23 Cleaning fluid 25 Fixing hole 30 Transducers 40 Oscillator 50 Main body (control means) 51 Arithmetic section 52 Storage section 53 Judgment section 54 Display section 55 Input section 60 External equipment 61 Control device 100, 600 Ultrasonic cleaning equipment 110, 210, 310, 410, 510 Support 110a, 210a, 310a tip 110b, 210b, 310b rear end 110c Rear end surface 111, 112, 113 Slope 121, 122, 123 Sound pressure sensor 131 First signal line 141, 142, 143 connecting lines 151, 152, 153 Second signal line 211 Outer surface 221, 222, 223 Sound pressure sensor 311, 312, 313, 314 External surface 321, 322, 323, 324 Sound pressure sensor 411, 511 bottom 412, 512 Inner surface 413, 513 Lid 421, 422, 423 Sound pressure sensor 430, 530 Connectors 440, 540 Cable 451, 452, 453 Sound pressure sensor 514 Main body 514a Outer surface 515 Disc 516 Nut 521, 522, 523 Sound pressure sensor 551, 552, 553 Sound pressure sensor Ave Average sound pressure value of the upper sound pressure sensor AX1, AX2, AX3, AX4, AX5 center axis I Initial sound pressure value Min Sound pressure value of the lowest sound pressure sensor Min X,Y Threshold

Claims

1. A cleaning tank containing a cleaning liquid; A vibrator that irradiates ultrasonic waves to the cleaning tank; an oscillator that applies a drive signal to the transducer to generate the ultrasonic waves, A detection body for detecting a sound pressure of the cleaning liquid, A support at least partially immersed in the cleaning solution; a plurality of sound pressure sensors disposed at equal intervals around a central axis of the support in a non-liquid-contacting portion of the support, the sound pressure sensors having the same detection characteristics; Each of the plurality of sound pressure sensors detects the vibration caused by the ultrasonic wave propagated through the support as a sound pressure value. A detection body characterized by:

2. A cleaning tank containing a cleaning liquid; A vibrator that irradiates ultrasonic waves to the cleaning tank; an oscillator that provides the transducer with a drive signal for generating the ultrasonic wave; a support having at least a tip portion immersed in the cleaning liquid; and a detection body including a plurality of sound pressure sensors arranged at equal intervals around a central axis of the support at a rear end portion of the support and having the same detection characteristics, wherein each of the plurality of sound pressure sensors detects vibrations caused by the ultrasonic waves propagated through the support as a sound pressure value; A control means to which the detection body is connected, The control means determines whether the operating state of the ultrasonic cleaning device is normal or abnormal based on the detection result of the detection object. An ultrasonic cleaning device characterized by:

3. The control means a determination unit that determines whether an operating state of the detection object is normal or abnormal based on the sound pressure values ​​detected by each of the plurality of sound pressure sensors; A display unit capable of displaying a detection result by the detection object, The determination unit sets the plurality of sound pressure sensors as one lower sound pressure sensor having the smallest sound pressure value and upper sound pressure sensors excluding the lower sound pressure sensor, and determines whether the operating state of the detection object is normal or abnormal based on a lower sound pressure value detected by the lower sound pressure sensor and a reference sound pressure value corresponding to the upper sound pressure value detected by the upper sound pressure sensor.

3. The ultrasonic cleaning device according to claim 2 .

4. The determination unit determines whether the operating state of the detection object is normal or abnormal based on a comparison result between the product of the reference sound pressure value and a predetermined threshold value and the lower sound pressure value.

4. The ultrasonic cleaning device according to claim 3,

5. When the number of the plurality of sound pressure sensors is three or more, the reference sound pressure value is an average value of the upper sound pressure values ​​of the top two upper sound pressure sensors having larger sound pressure values ​​among the upper sound pressure sensors.

5. The ultrasonic cleaning device according to claim 4,

6. The determination unit determines whether an operating state of the oscillator is normal or abnormal based on the presence or absence of an output of the drive signal from the oscillator.

6. The ultrasonic cleaning device according to claim 5,

7. The determination unit determines whether an operating state of the transducer is normal or abnormal based on a comparison result between a predetermined initial sound pressure value and the reference sound pressure value.

7. The ultrasonic cleaning device according to claim 6,

8. When the number of the plurality of sound pressure sensors is two, the reference sound pressure value is the upper sound pressure value detected by one of the upper sound pressure sensors.

5. The ultrasonic cleaning device according to claim 4,

9. A control device is provided that outputs a stop signal to stop the operation of the ultrasonic cleaning device when the determination unit determines that the operating state of the detection body is abnormal.

4. The ultrasonic cleaning device according to claim 3,