JP2007143630A - Vibration sensor, unbalance sensor and washing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a washing machine correctly judging an unbalanced state. <P>SOLUTION: The washing machine is provided with a washing tank 11 driven by a motor 14, a rotary body unit part 20 for transmitting a torque of the motor 14 to the tank 11, a vibration sensor 30 provided on or near the unit part 20 and for sensing vibrations caused by the unit part 20, a transmission sound sensor 40 for sensing sounds caused by the vibrations and a control means for judging a state of the tank 11 by pieces of information from the vibration sensor 30 and the sound sensor 40 to control rotations of the motor 14 from the judgement result. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vibration detection apparatus that effectively detects vibration generated when a movable body is operated in an apparatus in which a movable body serving as a vibration generation source is installed in a housing. The present invention also relates to an unbalance detection device that detects an unbalance state from vibrations detected by the vibration detection device and sounds generated along with the vibrations. Furthermore, the present invention relates to a washing machine that effectively determines an unbalanced state.

  Conventionally, various washing machines have been proposed in which vibration and noise generated during operation of a washing machine in which a washing tub serving as a vibration generation source is installed are controlled to be small. As such, it is provided with an unbalance detection device and an acceleration detection device for detecting the amplitude at the time of resonance of the outer tub exceeding the allowable value and the amplitude at the time of steady rotation, respectively, and outputs of the unbalance detection device and the acceleration detection device. Based on the signal, the rotation of the variable speed motor, drum, etc. is controlled to correct the cloth slippage when the amount of cloth slippage is large and difficult to start dewatering. Accordingly, there has been proposed a “drum-type washing machine that performs a dehydrating operation by lowering the upper limit of the steady dewatering speed” (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 10-244091 (page 4-5, FIG. 2)

  The drum-type washing machine described in Patent Literature 1 reduces the number of times of re-dehydration due to a shift of the laundry (unbalanced state) based on the output signals of the amplitude detection means and the vibration detection means during dehydration, and reduces the vibration transmission force and Noise is reduced. However, even if a vibration that does not hinder the operation of the washing machine occurs, the vibration is detected by the amplitude detecting means and the vibration detecting device, the unbalanced state is corrected, and dehydration is performed again.

  In other words, the cycle of occurrence of an unbalanced state, suspension of operation, restoration of the unbalanced state, and resumption of operation is repeated every time an unbalance occurs, and a lot of time is spent until one washing is completed. There was a problem. In addition, the user who uses the washing machine often feels uncomfortable from the sound generated by the unbalanced state rather than the vibration generated by the unbalanced state.

  The present invention has been made to solve the above-described problems, and effectively detects vibrations generated when a movable body is operated in a device in which the movable body serving as a vibration generation source is installed in the casing. A detection device is provided. Moreover, the unbalance detection apparatus which detects an unbalance state from the vibration which the vibration detection apparatus detected, and the sound which generate | occur | produces with the vibration is provided. Furthermore, the present invention relates to a washing machine that accurately determines an unbalanced state.

  A vibration detection device according to the present invention includes a piezoelectric element that converts a vibration generated by a movable body that is a vibration generation source into a voltage signal and outputs the voltage signal, and a weight that is attached to the piezoelectric element and amplifies the vibration applied to the piezoelectric element. It is provided with.

  In addition, the unbalance detection device according to the present invention converts a vibration generated by a movable body as a vibration generation source into a voltage signal and outputs the voltage signal, and is attached to the piezoelectric element to amplify the vibration applied to the piezoelectric element. A vibration detection device made of a weight of the above, a sound detection device for detecting sound generated by the movable body, and a control means for judging the state of the movable body based on information from the vibration detection device and the sound detection device. It is characterized by that.

  The washing machine according to the present invention further includes a washing tub that accommodates laundry and is driven by a motor, a rotating shaft that transmits the rotational force of the motor to the washing tub, and a rotating ball that assists the rotating operation of the rotating shaft. And a piezoelectric element that converts the vibration generated in the rolling element unit into a voltage signal and outputs the voltage signal, and a weight that is attached to the piezoelectric element and amplifies the vibration applied to the piezoelectric element. The state of the washing tub is determined from the vibration detection device, the sound detection device that detects the sound generated in the rolling element unit, and the information from the vibration detection device and the sound detection device, and the rotation of the motor is controlled based on the result. And a control means for performing the above.

  A vibration detection device according to the present invention includes a piezoelectric element that converts a vibration generated by a movable body that is a vibration generation source into a voltage signal and outputs the voltage signal, and a weight that is attached to the piezoelectric element and amplifies the vibration applied to the piezoelectric element. Therefore, vibration can be detected efficiently regardless of the magnitude of the generated vibration.

  In addition, the unbalance detection device according to the present invention converts a vibration generated by a movable body as a vibration generation source into a voltage signal and outputs the voltage signal, and is attached to the piezoelectric element to amplify the vibration applied to the piezoelectric element. A vibration detection device made of a weight of the above, a sound detection device for detecting sound generated by the movable body, and a control means for judging the state of the movable body based on information from the vibration detection device and the sound detection device. Therefore, it is possible to appropriately judge the unbalanced state.

  The washing machine according to the present invention further includes a washing tub that accommodates laundry and is driven by a motor, a rotating shaft that transmits the rotational force of the motor to the washing tub, and a rotating ball that assists the rotating operation of the rotating shaft. And a piezoelectric element that converts the vibration generated in the rolling element unit into a voltage signal and outputs the voltage signal, and a weight that is attached to the piezoelectric element and amplifies the vibration applied to the piezoelectric element. The state of the washing tub is determined from the vibration detection device, the sound detection device that detects the sound generated in the rolling element unit, and the information from the vibration detection device and the sound detection device, and the rotation of the motor is controlled based on the result. Since the control means is provided, the unbalanced state in the washing tub can be reliably determined and the washing time can be shortened.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is a longitudinal sectional view showing a schematic configuration of a washing machine 100 according to Embodiment 1 of the present invention. In the first embodiment, a case where the washing machine 100 is a drum type washing machine (washing tub inclined type washing machine) will be described as an example.

  As shown in FIG. 1, the washing machine 100 according to the first embodiment includes an outer tub 12 inclined in the housing 10, a damper 13 that elastically holds the outer tub 12 from below, and a front surface 15 of the housing 10. , A support rubber body 17 for connecting the outer tub 12 and the door 16 of the front surface 15, a suspension spring 18 for statically supporting the outer tub 12, and driving the outer tub 12. Motor 14, a rolling element unit 20 that transmits the driving force of the motor 14 to the outer tub 12, a vibration detection device 30 that detects vibration generated in the outer tub 12, and a sound generated in the outer tub 12. A transmitted sound detection device 40 (sound detection device).

  The outer tub 12 includes a laundry tub 11 for storing laundry such as clothes. The washing tub 11 serves as a washing tub for washing the laundry and a dehydration tub for dehydrating the laundry. The damper 13 is not particularly limited as long as it can elastically hold the outer tub 12 from below. The washing machine 100 is provided with main components such as a heater and a heat pump (not shown). This heater or heat pump is used for warming the water used for washing or rinsing and for warming the dry air.

  Furthermore, the washing machine 100 includes control means (not shown) for controlling the operation of the motor 14. That is, the control means controls the motor 14 based on detection information from the vibration detection device 30 and the transmitted sound detection means 40 described in detail later. Further, the control means is adapted to control the motor 14 according to the operation process such as easy washing, dehydration, and drying, and may be constituted by a microcomputer or the like. The rolling element unit 20 is generally referred to as a bearing (details will be described with reference to FIG. 2).

  The vibration detection device 30 includes a fixed end 31 that is fixed to a location (for example, the rolling element unit 20) where vibration is to be detected, a piezoelectric element 32 that converts the generated vibration into a voltage, and a weight 33 that amplifies the generated vibration. It consists of The vibration detection device 30 is characterized in that a weight 33 for amplifying the generated vibration is provided in order to efficiently detect the generated vibration. Therefore, in this vibration detection device 30, even if the generated vibration is small, the vibration is amplified by the weight 33, so that the piezoelectric element 32 is forcibly bent, and the vibration is caused by the amount of voltage generated by the voltage effect of the piezoelectric element 32. The level can be reliably detected.

  The fixed end 31 may be anything that can be fixed to a location where vibration is desired to be detected. For example, the fixed end 31 may be composed of a magnet or the like. However, if it cannot be fixed at the location where vibration is detected, it may be fixed near the location. The piezoelectric element 32 is not particularly limited as long as it can convert the generated vibration into a voltage. For example, the piezoelectric element 32 may be made of PZT (lead zirconate titanate) or the like.

  The weight 33 is not particularly limited as long as it can amplify the generated vibration. For example, a weight made of wood, plastic, rubber or the like may be used as a substitute for the weight 33. 1 shows a case in which the weight 33 is provided on both surfaces of the piezoelectric element 32 at an arbitrary position, but the weight 33 may be provided on only one surface of the piezoelectric element 32. Note that the vibration information detected by the vibration detection device 30 is transmitted to a control means (not shown).

  The transmitted sound detection device 40 includes a vibration film for detecting air vibration (sound) propagating in space. For example, the transmitted sound detection device 40 may be configured by a microphone or the like that converts sound into an electrical signal. In addition, the transmitted sound detection device 40 may be configured to cover the outside with a molded product of a vibration-proof material in order to reliably detect sound propagating in the air. By doing so, the vibration component propagating to the housing 10 can be removed by the vibration-proof material, and the sound propagating in the air can be detected efficiently. As this vibration isolating material, rubber having a low hardness (10 ° C. or less) may be used.

  In general, the washing machine 100 installed in a living environment is often partitioned by furniture and walls except for the front surface 15. That is, the sound sensed by the user is often emitted from the front surface 15 of the washing machine 100. Therefore, the transmitted sound detection device 40 is preferably mounted on the front surface 15 in the housing 10 as shown in FIG. However, the present invention is not limited to this. For example, the mounting location may be determined according to the location where the washing machine 100 is installed. Note that the sound information detected by the transmitted sound detection device 40 is transmitted to a control means (not shown).

  In the first embodiment, the unbalance detection device is configured by the vibration detection device 30, the transmitted sound detection device 40, and control means (not shown). That is, vibration generated in the rolling element unit 20 is detected by the vibration detection device 30, and sound generated in the rolling element unit 20 is detected by the transmitted sound detection device 40. The unbalanced state is judged. (Details are described in FIG. 3).

  FIG. 2 is an enlarged cross-sectional view showing details of the rolling element unit 20. The rolling element unit 20 is generally called a bearing, is connected to the motor 14, and supports the rotating shaft 21 that transmits the driving force of the motor 14 to the outer tub 12, the rotating shaft 21, and the rotating shaft. And a rotating sphere 22 for smoothly rotating 21. The rotating sphere 22 is housed in a rotating sphere case 23 filled with lubricating oil such as grease, and is in contact with the rotating shaft 21 penetrating the rotating sphere case 23 in the rotating sphere case 23. It has become.

  In FIG. 2, the case where the vibration detection apparatus 30 is being fixed to the rolling element unit part 20 is shown as an example. That is, it is desirable that the vibration detection device 30 be mounted at a location where vibration is desired to be detected. This is because the target vibration can be directly detected. The vibration propagating to the casing 10 of the washing machine 100 is generated in the rolling element unit 20 provided in the outer tub 12. That is, the vibration generated by the collision between the rotating shaft 21 and the rotating sphere 22 in the rolling element unit portion 20 propagates to the housing 10.

  In particular, large vibrations (abnormal vibrations) often occur at the stage of shifting from low-speed rotation at the start of dehydration to high-speed rotation. This is because when the washing tub 11 rotates in a state where the laundry in the washing tub 11 is offset (unbalanced), the contact state between the rotating shaft 21 and the rotating ball 22 in the rolling element unit portion 20 is reduced. This is because it fluctuates greatly compared to the contact state during normal operation. In the case of a washing tub inclined type washing machine such as the washing machine 100, an unbalanced state is likely to occur, and abnormal vibration is remarkable.

  In addition, sound is generated with the occurrence of vibration. A user who uses the washing machine 100 often feels uncomfortable by sensing sound rather than vibration. This can be understood by considering user complaints in the market. In other words, there are more claims for sound in the market than for claims for vibration itself. The sensitivity of the human ear depends on the frequency of the sound that reaches the ear. Therefore, even sounds with the same sound pressure level are felt differently depending on their frequencies. Generally, the sound (abnormal sound) that the user determines to be unpleasant is a peak frequency component in a frequency band of 1 kHz (kilohertz) or less.

  This peak frequency component coincides with the rotational component obtained by multiplying the number of rotating spheres 22 in the rolling element unit 20 by the rotational speed. That is, the frequency component of this rotational component is generated as an abnormal vibration component inside the rolling element unit 20, propagates in the air, passes through the housing 10, and is radiated to the outside as an abnormal sound (noise). It is. And as above-mentioned, since it is often partitioned with furniture and the wall except the front surface 15 of the washing machine 100, most of the sound is radiated from the front surface 15. Therefore, the user feels uncomfortable by feeling the emitted sound as noise.

  Next, a mechanism for determining an unbalanced state from generated vibrations and sounds will be described. FIG. 3 is an explanatory diagram for determining an unbalanced state. FIG. 3A is an explanatory diagram showing the frequency characteristics of vibrations that occur during normal operation and vibrations that occur during operation in an unbalanced state. In FIG. 3A, the vertical axis represents the vibration level (dB) and the horizontal axis represents the frequency (Hz).

  FIG. 3A shows a case where the peak frequency component of vibration generated during normal operation and vibration generated during operation in an unbalanced state is about 300 Hz. In other words, the vibration that occurs during normal operation indicates that the vibration level is small and does not cause abnormal vibration even when the peak frequency is about 300 Hz. On the other hand, the vibration generated during operation in an unbalanced state indicates that the vibration level is very large and the abnormal vibration occurs when the peak frequency is about 300 Hz.

  FIG. 3B is an explanatory diagram showing the frequency characteristics of sound generated during normal operation and sound generated during operation in an unbalanced state. In FIG. 3B, the vertical axis indicates the sound pressure level (dB) and the horizontal axis indicates the frequency (Hz). FIG. 3B shows a case where the peak frequency component of the sound generated during normal operation and the sound generated during operation in an unbalanced state is about 300 Hz, as in FIG. 3A.

  In other words, the sound generated during normal operation indicates that even if the peak frequency is about 300 Hz, the sound pressure level is small and does not become abnormal sound. On the other hand, the sound generated during operation in an unbalanced state indicates that the sound pressure level is very high and the sound becomes abnormal when the peak frequency is about 300 Hz. From FIG. 3A and FIG. 3B, it can be seen that the magnitude of the generated sound changes according to the magnitude of the vibration.

  Whether or not the user feels uncomfortable is determined by the volume of the sound. Therefore, even when driving in an unbalanced state, if the vibration level is low and the sound pressure level is low, the user will not be uncomfortable even if the driving is continued. If the washing tub 11 is stopped even in such a case, a lot of time is consumed until the washing is completed, and energy is wasted. Therefore, if the generated sound does not cause discomfort to the user, it is preferable to continue driving and reduce the time required for washing.

  FIG. 3C is an explanatory diagram for determining an unbalanced state from the generated vibration and the generated sound. As shown in FIG. 3B, the sound that the user feels uncomfortable (abnormal sound) exceeds a predetermined value. Whether or not the generated sound is abnormal is determined by the magnitude of vibration that causes the generation of the sound. Therefore, the unbalance detection apparatus according to Embodiment 1 uses the cross-correlation function to determine that an abnormal sound that the user feels uncomfortable has occurred.

  The cross-correlation function is to obtain a correlation between a vibration waveform and a sound pressure waveform and to calculate a similarity degree therefrom. This unbalance detection device utilizes the property (coherence) that the vibration and sound pressure frequencies interfere with each other, so that the vibration frequency generated by the rolling element unit 20 detected by the vibration detection device 30 is detected as transmitted sound. The unbalanced state of the washing tub 11 is determined by analyzing which of the frequency bands of the sound generated by the rolling element unit portion detected by the device 40 contributes.

  In other words, the cross-correlation processing using the cross-correlation function is a frequency component that matches (contributes) from the frequency component of the vibration generated in the rolling element unit 20 and the frequency component of the acoustic characteristics of the generated sound. The degree of coincidence (contribution) is calculated. Then, the unbalance detection apparatus determines whether or not an unbalance has occurred depending on whether or not the contribution exceeds a threshold (for example, 0.8) set arbitrarily.

  That is, in the unbalance detection device, when the calculated contribution degree exceeds the threshold value, abnormal sound due to abnormal vibration in the rolling element unit 20 is emitted from the front surface 15 as transmitted sound (noise) to the outside. If the threshold value is not exceeded, that is, if the vibration and sound are generated in the rolling element unit 20, sound emission (noise) from the front surface 15 is transmitted to the outside as transmitted sound. ) (Ie, not in an unbalanced state).

  By doing this, it is possible to detect the sound generated by the vibration generated in the rolling element unit 20 and to continue the operation such as dehydration work if the vibration does not contribute as an abnormal sound. It can be determined that the user does not feel uncomfortable. Therefore, during the dehydrating operation of the washing machine 100, the low-speed rotation can be surely shifted to the high-speed rotation, and the time required for washing can be saved. In addition, when an abnormal sound that the user feels uncomfortable is emitted, an operation for correcting the unbalanced state is performed, which reduces the number of complaints from the user in the market.

  In addition, although FIG. 3 demonstrated as an example the case where the frequency which the abnormal vibration and abnormal sound which an unbalanced state generate | occur | produces is 300 Hz, it does not limit to this. For example, the peak frequency setting may be changed according to the user group using the washing machine 100. Moreover, although the case where the peak frequency is only 300 Hz has been described as an example, the present invention is not limited to this, and there may be two or more. Furthermore, although the case where the threshold value is set to 0.8 has been described as an example, the present invention is not limited to this. For example, the settings may be adjusted according to the surrounding environment and purpose (for home use, business use, etc.) where the washing machine 100 is installed.

  Next, the flow of processing when determining an unbalanced state will be described. FIG. 4 is a flowchart showing the flow of processing when determining an unbalanced state that occurs during dehydration. First, the washing machine 100 starts a dehydration operation. And the vibration detection apparatus 30 detects the vibration which generate | occur | produces in the rolling element unit part 20 (step S101). That is, the vibration is detected by detecting the frequency component of the rotational vibration of the rotating sphere 22 in the rolling element unit 20.

  In addition, the transmitted sound detection device 40 detects a sound generated in the rolling element unit 20 (step S102). That is, sound that is transmitted sound is detected by detecting the frequency component of the sound that has propagated to the front surface 15 of the housing 10. The vibration detection device 30 and the transmitted sound detection device 40 transmit the detected information to a control unit (not shown). And a control means judges an unbalanced state based on the received information.

  First, the control means calculates a contribution based on information from the vibration detection device 30 and the transmitted sound detection device 40 (step S103). And a control means judges the presence or absence of an unbalanced state by whether the calculated contribution degree exceeds the threshold value (step S104). When it is determined that the calculated contribution degree exceeds a threshold value (for example, 0.8) (step S104; YES), the control unit stops the rotation of the motor 14 (step S105).

  In this case, it is determined that an abnormal sound due to the unbalanced state has occurred, and the dehydration operation is temporarily stopped. Then, the control means controls the motor 14 so as to correct the unbalanced state (step S106). That is, the motor 14 is operated so as to loosen the laundry in the washing tub 11 and the unbalanced state is corrected. When the control means determines that the unbalanced state has been corrected, the control means controls the motor 14 to resume the dehydration operation. Then, the determination of the unbalanced state is performed again.

  On the other hand, when it is determined that the calculated contribution does not exceed a threshold (for example, 0.8) (step S104; NO), the control unit continues the rotation of the motor 14 (step S107). In this case, it is determined that there is no abnormal sound associated with the unbalanced state, and the dehydrating operation is continued (step S107). Then, the low-speed rotation is changed to the high-speed rotation, and the dehydration operation is completed. In this way, the unbalanced state can be reliably detected and the time required for the dehydration operation can be saved.

Embodiment 2. FIG.
FIG. 5 is a longitudinal sectional view showing a schematic configuration of a washing machine 100a according to Embodiment 2 of the present invention. In the second embodiment, differences from the first embodiment will be mainly described, and the same parts as those in the first embodiment will be denoted by the same reference numerals and description thereof will be omitted. In this Embodiment 2, the case where the washing machine 200 is a vertical type washing machine (washing tub vertical arrangement type washing machine) is shown as an example.

  As shown in FIG. 5, the washing machine 100a according to the second embodiment drives the outer tub 12a vertically arranged in the housing 10a, the suspension bar 19 that holds the outer tub 12a in a suspended manner, and the outer tub 12a. Motor 14a, a rolling element unit 20a that transmits the driving force of the motor 14a to the outer tub 12a, a vibration detection device 30a that detects vibration generated in the outer tub 12a, and a sound generated in the outer tub 12a And a transmitted sound detection device 40a (sound detection device).

  The outer tub 12a includes a laundry tub 11a for storing laundry such as clothes. The washing tub 11a serves as a washing tub for washing the laundry and a dehydration tub for dehydrating the laundry. The hanging rod 19 is not particularly limited as long as it can suspend and hold the outer tub 12a. The washing machine 100a is provided with main components such as a heater and a heat pump (not shown).

  Furthermore, the washing machine 100a includes control means (not shown) for controlling the operation of the motor 14a. That is, the control means controls the motor 14a based on detection information from the vibration detection device 30a and the transmitted sound detection means 40a. Further, the control means performs control according to the driving process such as easy washing, dehydration, and drying of the motor 14a, and may be configured by a microcomputer or the like.

  In Embodiment 2, the case where the vibration detection device 30a is fixed to the rolling element unit 20a is shown as an example. That is, the arrangement position of the vibration detection device 30a is different from the vibration detection device 30 described in the first embodiment. Therefore, as described with reference to FIG. 2, the fixed end 31a of the vibration detection device 30a is fixed to the rolling element unit 20a, so that vibration generated in the rolling element unit 20a is efficiently detected. be able to.

  The rolling element unit 20a, the vibration detection device 30a, and the transmitted sound detection device 40a are the same as the rolling element unit 20, the vibration detection device 30, and the transmitted sound detection device 40 described in the first embodiment. In the second embodiment, it is assumed that the vibration detection device 30a, the transmitted sound detection device 40a, and control means (not shown) constitute an unbalance detection device. The mechanism for determining the unbalanced state from the generated vibration and sound is the same as in the first embodiment.

  Therefore, as in the first embodiment, the sound generated by the vibration generated in the rolling element unit 20a can be detected, and even if the vibration is generated, if it does not contribute as an abnormal sound, such as dehydration work. Even if driving is continued, it can be determined that the user does not feel uncomfortable. Further, at the time of dehydration work of the washing machine 100a, it is possible to surely shift from the low speed rotation to the high speed rotation, and the time required for washing can be saved. In addition, when an abnormal sound that the user feels uncomfortable is emitted, an operation for correcting the unbalanced state is performed, which reduces the number of complaints from the user in the market.

  In each embodiment, the washing tub inclined arrangement type and the washing tub vertical arrangement type washing machines have been described as examples, but the present invention is not limited thereto. For example, the washing machine may be a horizontal arrangement type washing machine. Moreover, although the case where the vibration detection apparatus 30 was applied to the washing machine was demonstrated to the example, it is not limited to this. For example, the vibration detection device 30 can be applied to a device other than a washing machine in which a movable body serving as a vibration generation source is installed in a housing.

  Furthermore, although the case where the unbalance detection apparatus is applied to a washing machine has been described as an example, the present invention is not limited to this. For example, the unbalance detection device is applied to a device other than a washing machine that determines the state of the movable body from vibration generated by the movable body that is a vibration generation source in the housing and sound generated by the vibration. be able to. That is, although it was set as the unbalance detection apparatus in order to detect the unbalance state in the washing tub 11, it should just be able to judge a state from a vibration and a sound, and is not restricted to the detection of an unbalance state.

It is a longitudinal cross-sectional view which shows schematic structure of the washing machine which concerns on Embodiment 1. FIG. It is an expanded sectional view which shows the detail of a rolling element unit part. It is explanatory drawing for judging an unbalanced state. It is a flowchart which shows the flow of a process at the time of judging the unbalance state which generate | occur | produces at the time of spin-drying | dehydration. It is a longitudinal cross-sectional view which shows schematic structure of the washing machine which concerns on Embodiment 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 housing | casing, 10a housing | casing, 11 washing tub, 11a washing tub, 12 outer tub, 12a outer tub, 13 damper, 14 motor, 14a motor, 15 front, 16 door, 17 support rubber, 18 suspension spring, 19 suspension rod 20 rolling element unit, 20a rolling element unit, 21 rotating shaft, 22 rotating sphere, 23 rotating sphere case, 30 vibration detecting device, 30a vibration detecting device, 31 fixed end, 31a fixed end, 32 piezoelectric element, 33 Weight, 40 transmitted sound detection device, 40a transmitted sound detection device, 100 washing machine, 100a washing machine.

Claims (8)

A piezoelectric element that converts a vibration generated by a movable body that is a vibration generation source into a voltage signal and outputs the voltage signal;
A vibration detection apparatus comprising: a weight attached to the piezoelectric element and amplifying vibration applied to the piezoelectric element. A piezoelectric element that converts a vibration generated by a movable body that is a vibration generation source into a voltage signal and outputs the voltage signal;
A vibration detector attached to the piezoelectric element and comprising a weight for amplifying vibration applied to the piezoelectric element;
A sound detection device for detecting sound generated by the movable body;
An imbalance detection device comprising: control means for determining a state of the movable body based on information from the vibration detection device and the sound detection device. The control means includes
Calculating a contribution ratio that is a degree of coincidence between a frequency component of vibration generated in the movable body and a frequency component of acoustic characteristics of the generated sound, and determining whether the contribution ratio exceeds a predetermined threshold The imbalance detection device according to claim 2, wherein the state of A laundry tub containing laundry and driven by a motor;
A rolling element unit having a rotating shaft that transmits the rotational force of the motor to the washing tub, and a rotating ball that assists the rotating operation of the rotating shaft;
A vibration detection device comprising: a piezoelectric element that converts a vibration generated in the rolling element unit into a voltage signal and outputs the voltage signal; and a weight attached to the piezoelectric element for amplifying the vibration applied to the piezoelectric element;
A sound detection device for detecting a sound generated in the rolling element unit;
A washing machine comprising: control means for determining a state of the washing tub based on information from the vibration detection device and the sound detection device, and controlling rotation of the motor based on the result. The control means includes
A contribution rate that is a degree that the frequency component of the vibration generated in the rolling element unit portion matches the frequency component of the acoustic characteristics of the generated sound is calculated, and whether or not the contribution rate exceeds a predetermined threshold The state of a rolling element unit part is judged. The washing machine according to claim 4 characterized by things. The control means includes
The washing machine according to claim 4 or 5, wherein when the calculated contribution rate exceeds a predetermined threshold, it is determined that an unbalanced state has occurred in the washing tub. The washing machine according to any one of claims 4 to 5, wherein the sound detection device includes a microphone. The sound detection device
The washing machine according to any one of claims 4 to 7, wherein the washing machine is installed at a location where sound generated in the rolling element unit portion is transmitted and transmitted to the outside.

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