CN108469329A - A kind of detecting system of washing machine non-equilibrium state - Google Patents
A kind of detecting system of washing machine non-equilibrium state Download PDFInfo
- Publication number
- CN108469329A CN108469329A CN201810231884.XA CN201810231884A CN108469329A CN 108469329 A CN108469329 A CN 108469329A CN 201810231884 A CN201810231884 A CN 201810231884A CN 108469329 A CN108469329 A CN 108469329A
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- China
- Prior art keywords
- resistance
- operational amplifier
- signal
- connect
- washing machine
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M1/00—Testing static or dynamic balance of machines or structures
- G01M1/14—Determining unbalance
- G01M1/16—Determining unbalance by oscillating or rotating the body to be tested
- G01M1/18—Determining unbalance by oscillating or rotating the body to be tested and running the body down from a speed greater than normal
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M1/00—Testing static or dynamic balance of machines or structures
- G01M1/14—Determining unbalance
- G01M1/16—Determining unbalance by oscillating or rotating the body to be tested
- G01M1/22—Determining unbalance by oscillating or rotating the body to be tested and converting vibrations due to unbalance into electric variables
Abstract
The invention discloses a kind of detecting systems of washing machine non-equilibrium state, including：Sound transducer, signal pre-processing circuit, signal acquisition and conversion module, signal spectral analysis module, control module and keyboard and display module, the wherein described sound transducer is connect with the signal pre-processing circuit, the signal pre-processing circuit is connect with the signal acquisition with conversion module, and the control module is connect with the signal acquisition with conversion module, the signal spectral analysis module and the keyboard with display module respectively.The present invention utilizes the non-equilibrium state of noise measuring washing machine, when washing machine occurs to be more than predetermined uneven trend, timely reduction of speed or out of service.And it is relatively low using the scheme cost that sound transducer judges, it is suitble to household appliances.
Description
Technical field
The present invention relates to washing machine technology fields, particularly relate to a kind of detecting system of washing machine non-equilibrium state.
Background technology
In use, the problem that needing most prevents is exactly washing machine in high speed washing or dehydration to washing machine
It is middle to topple over.Especially during laundry machine dehydration, may due in bucket load distribution it is uneven cause systematic eccentricity compared with
Greatly, to cause system centrifugal force larger, the situations such as generation outer barrel is hit babinet or complete machine displacement or even toppled over.
Occur compared with large eccentricity when to avoid dehydration, traditional method, which is washing machine controller, to be needed to pass through before high speed dewatering
Weigh to bucket undergarment, then by being run to washing machine when speed and electric current detection with preset normal value carry out
Comparison, to judge whether washing machine is in non-equilibrium state, this method can be the side of nearest 20 years mainstreams currently on the market
Case, but due to being a kind of method judged indirectly by electric signal, so not being accurately very high, occasional, which goes out, first judges by accident,
And since error rate is higher, about 15% error rate, so actual market product usually normality threshold is set it is relatively low, with
Reliability is improved, therefore limits the maximum washability of washing machine.
Therefore, there is an urgent need for a kind of new technologies of design to improve its problem by the present inventor.
Invention content
The present invention is intended to provide a kind of detecting system of washing machine non-equilibrium state, not using noise measuring washing machine
Equilibrium state, when washing machine occurs to be more than predetermined uneven trend, timely reduction of speed or out of service.
In order to solve the above technical problems, the technical scheme is that：
A kind of detecting system of washing machine non-equilibrium state, including：Sound transducer, signal pre-processing circuit, signal are adopted
Collection and conversion module, signal spectral analysis module, control module and keyboard and display module, wherein the sound transducer and institute
Signal pre-processing circuit connection is stated, the signal pre-processing circuit is connect with the signal acquisition with conversion module, the control
Module connects with the signal acquisition and conversion module, the signal spectral analysis module and the keyboard and display module respectively
It connects.
Preferably, the signal pre-processing circuit include sequentially connected input signal supercircuit, impedance matching circuit,
Low-pass filter circuit, trap circuit and level shifting circuit, wherein the input signal supercircuit includes resistance R7, resistance
R10, resistance R11, resistance R12, operational amplifier U2A, the same phase of the resistance R7, resistance R10 and the operational amplifier U2A
Input terminal connects；Resistance R11, resistance R12 one end connect with the inverting input of the operational amplifier U2A, resistance R12's
The other end is connect with the output end of the operational amplifier U2A.
Preferably, the low-pass filter circuit includes resistance R22, resistance R23, resistance R24, resistance R25, resistance R26, fortune
Amplifier U5A, capacitance C10 are calculated, wherein the resistance R22 connects after capacitance C10 with the in-phase input end of operational amplifier U5A
It connects；Resistance R23 is arranged between the inverting input and output end of operational amplifier U5A；The one end resistance R24 with pass through capacitance
It is connect with the in-phase input end of operational amplifier U5A after C10, the other end is connect with the output end of operational amplifier U5A；Resistance
The one end R25 is connect with the inverting input of operational amplifier U5A, other end ground connection；The one end resistance R26 and operational amplifier U5A
In-phase input end connection, the other end ground connection.
Preferably, the signal acquisition includes that conversion chip and the differential signal being attached thereto are converted with conversion module,
Described in differential signal conversion circuit include resistance R31, resistance R32, resistance R33, operational amplifier U3, transformer T1, wherein
The output end of the operational amplifier U3 is connect after resistance R31 with the first foot of transformer T1；The third foot of transformer T1
It is connect with conversion chip after resistance R32, the 4th foot of transformer T1 is connect after resistance R32 with conversion chip.
Preferably, the signal acquisition and conversion module further include a DA output processing circuits, the DA outputs processing electricity
Road specifically includes resistance R41, resistance R42, resistance R43, resistance R44, operational amplifier U4, wherein one end of the resistance R41
It is connect with the conversion chip, the other end is connect with the inverting input of the operational amplifier U4；One end of the resistance R42
It is connect with the conversion chip, the other end is connect with the in-phase input end of the operational amplifier U4；The resistance R43 settings exist
Between the inverting input and output end of the operational amplifier U4, the output of the resistance R44 and the operational amplifier U4
End connection.
Preferably, further include a clocked flip-flop circuit, connect with conversion module with the signal acquisition.
Preferably, the conversion chip is MAX4477 chips.
Preferably, the control module is microprocessor.
Preferably, the operational amplifier U2A is NJM2100 operational amplifiers.
Using above-mentioned technical proposal, the present invention includes at least following advantageous effect：
The detecting system of washing machine non-equilibrium state of the present invention utilizes the uneven shape of noise measuring washing machine
State, when washing machine occurs to be more than predetermined uneven trend, timely reduction of speed or out of service.And judged using sound transducer
Scheme cost it is relatively low, be suitble to household appliances.
Description of the drawings
Fig. 1 is the schematic diagram of the detecting system of washing machine non-equilibrium state of the present invention；
Fig. 2 is the circuit diagram of input signal supercircuit of the present invention；
Fig. 3 is the circuit diagram of low-pass filter circuit of the present invention；
Fig. 4 is the circuit diagram of differential signal conversion circuit of the present invention；
Fig. 5 is the circuit diagram of DA output processing circuits of the present invention；
Fig. 6 is the software flow pattern of the detecting system of washing machine non-equilibrium state of the present invention；
Fig. 7 is the program chart of Glitch Filter method algorithm.
Specific implementation mode
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation describes, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
As shown in Figures 1 to 5, for meet the present invention a kind of washing machine non-equilibrium state detecting system, including：Sound
Sensor, signal pre-processing circuit, signal acquisition and conversion module, signal spectral analysis module, control module and keyboard with it is aobvious
Show module, wherein the sound transducer is connect with the signal pre-processing circuit, the signal pre-processing circuit and the letter
Number acquisition is connect with conversion module, the control module respectively with the signal acquisition and conversion module, the signal spectrum point
Analysis module and the keyboard are connect with display module.
Preferably, the signal pre-processing circuit include sequentially connected input signal supercircuit, impedance matching circuit,
Low-pass filter circuit, trap circuit and level shifting circuit, wherein the input signal supercircuit includes resistance R7, resistance
R10, resistance R11, resistance R12, operational amplifier U2A, the same phase of the resistance R7, resistance R10 and the operational amplifier U2A
Input terminal connects；Resistance R11, resistance R12 one end connect with the inverting input of the operational amplifier U2A, resistance R12's
The other end is connect with the output end of the operational amplifier U2A.
Preferably, the low-pass filter circuit includes resistance R22, resistance R23, resistance R24, resistance R25, resistance R26, fortune
Amplifier U5A, capacitance C10 are calculated, wherein the resistance R22 connects after capacitance C10 with the in-phase input end of operational amplifier U5A
It connects；Resistance R23 is arranged between the inverting input and output end of operational amplifier U5A；The one end resistance R24 with pass through capacitance
It is connect with the in-phase input end of operational amplifier U5A after C10, the other end is connect with the output end of operational amplifier U5A；Resistance
The one end R25 is connect with the inverting input of operational amplifier U5A, other end ground connection；The one end resistance R26 and operational amplifier U5A
In-phase input end connection, the other end ground connection.
Preferably, the signal acquisition includes that conversion chip and the differential signal being attached thereto are converted with conversion module,
Described in differential signal conversion circuit include resistance R31, resistance R32, resistance R33, operational amplifier U3, transformer T1, wherein
The output end of the operational amplifier U3 is connect after resistance R31 with the first foot of transformer T1；The third foot of transformer T1
It is connect with conversion chip after resistance R32, the 4th foot of transformer T1 is connect after resistance R32 with conversion chip.
Preferably, the signal acquisition and conversion module further include a DA output processing circuits, the DA outputs processing electricity
Road specifically includes resistance R41, resistance R42, resistance R43, resistance R44, operational amplifier U4, wherein one end of the resistance R41
It is connect with the conversion chip, the other end is connect with the inverting input of the operational amplifier U4；One end of the resistance R42
It is connect with the conversion chip, the other end is connect with the in-phase input end of the operational amplifier U4；The resistance R43 settings exist
Between the inverting input and output end of the operational amplifier U4, the output of the resistance R44 and the operational amplifier U4
End connection.
Preferably, further include a clocked flip-flop circuit, connect with conversion module with the signal acquisition.
Preferably, the conversion chip is MAX4477 chips.
Preferably, the control module is microprocessor.
Preferably, the operational amplifier U2A is NJM2100 operational amplifiers.
In the present invention, superimposed signal circuit uses reversed summing circuit, and the output that signal is summed, amplifier uses
NJM2100。
Low-pass filter circuit part, due to require audio signal be 10KHz hereinafter, higher pure in order to make signal obtain
Degree, then need to filter out no signal, to improve the measuring precision.
The principle of low-pass filter is by the configuration to capacitance, resistance parameter so that analog filter is to frequency logical
The impedance of very little is presented in frequency component in band, and prodigious impedance is presented to out-of-band frequency component, in this way when load electricity
Signal is flowed by the signal extraction in passband can be come out when the analog bandpass filter, and the signal outside passband is gone
It removes.
R22, C13 form low-pass network in Fig. 3, and R26, C10 form high pass network, and the two series connection just constitutes passive band logical
Filter circuit adds a voltage follower in figure in the output end of band-pass circuit, is allowed to keep apart well with loading, three
Person constitutes a simple second order active bandwidth-limited circuit, since the input impedance of voltage follower is very high, output impedance
Characteristic very low and that have voltage amplification function, the connection for being changed to in-phase proportion amplifying circuit can be realized to filtering out
The voltage of signal is amplified, and by changing the value of R22, C13, R26, C10, can adjust the center frequency of bandwidth-limited circuit
Rate, the value by changing R23, R25 can adjust quality factor, gain and the bandwidth of bandwidth-limited circuit.Integrated circuit is simple,
The features such as component parameters are few, and circuit stability is good, adjustable gain.
In audio signal, influence of the power frequency 50HZ signals to system is maximum, therefore, is added 50HZ's in the signal processing
Trap circuit (hidden wave circuit).Calculating work formula is：F=1/2 π RC.
Since ADC can only acquire positive voltage, then need to raise signal, analysis calculate circuit need to add the direct current of 3V
It is flat, therefore devise level shifting circuit, since its circuit structure is custom circuit in the prior art, therefore the present embodiment to this not
It repeats.
Signal acquisition selects MAX4477 chips with conversion module, uses over-sampling (over sampling) ∑-Δ technology
(DA) and the high-resolution low speed signal of analog signal to digital signal (AD) from digital signal to analog signal is provided to convert.Tool
Body, single-ended signal is converted into differential signal using transformer and is input to MAX4477, as shown in Figure 4.
The value recommended in figure is 50 Ω, and resistance R32, resistance R33 are 22 Ω, and capacitance C31, capacitance C32 are 10 μ F, these yuan
The value of part can also be adjusted according to specific signal, and resistance value is between 10~100 Ω under general clear condition, and capacitance is 10
Between~200pF.
The DA outputs of MAX4477 are differential signal, can directly drive the load of 600 Ω.DA output processing circuits such as Fig. 5
It is shown.
By calculating, the sampling rate to analog signal is 25.6KHz, then needs the square wave for generating 25.6KHZR as A/D
The rate of change data, therefore clocked flip-flop circuit is devised, since its circuit structure is custom circuit in the prior art, therefore this
Embodiment does not repeat this.
Software aspects need to analyze noise content and filtered
This system Software for Design mainly realizes the analysis and display of Glitch Filter method algorithm and each frequency and corresponding power, by
It is expressed in C Plus Plus and operational capability is stronger and has portability well and hardware controls ability, then use C Plus Plus
It realizes.Overall program flow diagram is as shown in Figure 6.
Glitch Filter method is according to two decomposition method of base of DFT in the design, and in L, (L indicates operation stage from left to right
Number, L=1,2,3 ... M) in grade, two input datas of each butterfly are at a distance of a points of B (L-1), between same twiddle factor corresponds to
It is divided into 2 (M-L) a butterflies of 2L points.It since input terminal, carries out step by step, when carrying out L grades of operations, finds out 2 (L-1) successively no
Its corresponding 2 all (M-L) a butterfly has been calculated as soon as often finding out a twiddle factor in same twiddle factor.Therefore with multiple
Cyclic program realizes the transformation of Glitch Filter method.In-place computation is used simultaneously, can save a large amount of storage unit.Glitch Filter method is calculated
The program chart of method is as shown in Figure 7.
By software treated noise collection of illustrative plates and the comparison of the noise collection of illustrative plates of normal work, if it exceeds 15%, then it is assumed that
There are the danger toppled over, the automatic reduction of speed of washing machine to reach normal condition, and to record fault message.
Conclusion：The case where can effectively identifying vibration of washing machine noise by this structure design, and to shape will be toppled over
Noise when state is done to be judged and analyzes in advance, prevents washing machine from toppling over.
Because when washing machine imbalance when tilt state, noise has special variation, become low by original high-frequency noise
Frequency impact noise can effectively judge washing machine state by noise.The present invention uses the scheme that sound transducer judges
Cost is relatively low, is suitble to household appliances.This method can measure with conventional telecommunications number and correct and weight each other, be equivalent to original
On the basis of increase the measurement correction of safety and reliability a kind of, be equivalent to and increase a dimension, play and uneven judge that supplement is made
With；It, can also be to settings such as washing machine voice controls, including clamshell doors, shutdown, wash time additionally by sound transducer.
The foregoing description of the disclosed embodiments enables those skilled in the art to implement or use the present invention.
Various modifications to these embodiments will be apparent to those skilled in the art, as defined herein
General Principle can be realized in other embodiments without departing from the spirit or scope of the present invention.Therefore, of the invention
It is not intended to be limited to the embodiments shown herein, and is to fit to and the principles and novel features disclosed herein phase one
The widest range caused.
Claims (9)
1. a kind of detecting system of washing machine non-equilibrium state, which is characterized in that including：Sound transducer, Signal Pretreatment electricity
Road, signal acquisition and conversion module, signal spectral analysis module, control module and keyboard and display module, wherein the sound
Sensor is connect with the signal pre-processing circuit, and the signal pre-processing circuit connects with the signal acquisition and conversion module
Connect, the control module respectively with the signal acquisition and conversion module, the signal spectral analysis module and the keyboard with
Display module connects.
2. the detecting system of washing machine non-equilibrium state as described in claim 1, it is characterised in that：The Signal Pretreatment electricity
Road includes sequentially connected input signal supercircuit, impedance matching circuit, low-pass filter circuit, trap circuit and level conversion
Circuit, wherein the input signal supercircuit includes resistance R7, resistance R10, resistance R11, resistance R12, operational amplifier
U2A, the resistance R7, resistance R10 are connect with the in-phase input end of the operational amplifier U2A；The one of resistance R11, resistance R12
End is connect with the inverting input of the operational amplifier U2A, and the other end of resistance R12 is defeated with the operational amplifier U2A's
Outlet connects.
3. the detecting system of washing machine non-equilibrium state as claimed in claim 2, it is characterised in that：The low-pass filter circuit
Including resistance R22, resistance R23, resistance R24, resistance R25, resistance R26, operational amplifier U5A, capacitance C10, wherein the electricity
Resistance R22 is connect after capacitance C10 with the in-phase input end of operational amplifier U5A；Resistance R23 is arranged in operational amplifier U5A
Inverting input and output end between；The one end resistance R24 and the homophase input after capacitance C10 with operational amplifier U5A
End connection, the other end are connect with the output end of operational amplifier U5A；The anti-phase input of the one end resistance R25 and operational amplifier U5A
End connection, other end ground connection；The one end resistance R26 is connect with the in-phase input end of operational amplifier U5A, other end ground connection.
4. the detecting system of washing machine non-equilibrium state as described in any one of claims 1-3, it is characterised in that：The signal is adopted
Collection includes that conversion chip and the differential signal being attached thereto are converted with conversion module, wherein the differential signal conversion circuit includes
Resistance R31, resistance R32, resistance R33, operational amplifier U3, transformer T1, wherein the output end warp of the operational amplifier U3
It is connect with the first foot of transformer T1 after crossing resistance R31；The third foot of transformer T1 connects after resistance R32 with conversion chip
It connects, the 4th foot of transformer T1 is connect after resistance R32 with conversion chip.
5. the detecting system of washing machine non-equilibrium state as claimed in claim 4, it is characterised in that：The signal acquisition with turn
It further includes a DA output processing circuits to change the mold block, and the DA output processing circuits specifically include resistance R41, resistance R42, resistance
R43, resistance R44, operational amplifier U4, wherein one end of the resistance R41 is connect with the conversion chip, the other end with it is described
The inverting input of operational amplifier U4 connects；One end of the resistance R42 is connect with the conversion chip, the other end with it is described
The in-phase input end of operational amplifier U4 connects；The resistance R43 be arranged the operational amplifier U4 inverting input and
Between output end, the resistance R44 is connect with the output end of the operational amplifier U4.
6. the detecting system of washing machine non-equilibrium state according to any one of claims 1 to 5, it is characterised in that：Further include for the moment
Clock trigger circuit is connect with the signal acquisition with conversion module.
7. the detecting system of washing machine non-equilibrium state as claimed in claim 4, it is characterised in that：The conversion chip is
MAX4477 chips.
8. the detecting system of the washing machine non-equilibrium state as described in claim 1-7 is any, it is characterised in that：The control mould
Block is microprocessor.
9. the detecting system of washing machine non-equilibrium state as claimed in claim 2, it is characterised in that：The operational amplifier
U2A is NJM2100 operational amplifiers.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810231884.XA CN108469329A (en) | 2018-03-20 | 2018-03-20 | A kind of detecting system of washing machine non-equilibrium state |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810231884.XA CN108469329A (en) | 2018-03-20 | 2018-03-20 | A kind of detecting system of washing machine non-equilibrium state |
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| CN201810231884.XA Pending CN108469329A (en) | 2018-03-20 | 2018-03-20 | A kind of detecting system of washing machine non-equilibrium state |
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| CN101970744A (en) * | 2008-03-11 | 2011-02-09 | Bsh博世和西门子家用器具有限公司 | Laundry treatment appliance comprising a drum and a sensor, and method for the operation thereof |
| CN202382908U (en) * | 2011-12-29 | 2012-08-15 | 上海电机学院 | Shaft unbalanced fault simulation system of gearbox |
-
2018
- 2018-03-20 CN CN201810231884.XA patent/CN108469329A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1926413A (en) * | 2004-10-18 | 2007-03-07 | 日本精工株式会社 | Abnormality diagnosis system for machinery |
| CN101970744A (en) * | 2008-03-11 | 2011-02-09 | Bsh博世和西门子家用器具有限公司 | Laundry treatment appliance comprising a drum and a sensor, and method for the operation thereof |
| CN202382908U (en) * | 2011-12-29 | 2012-08-15 | 上海电机学院 | Shaft unbalanced fault simulation system of gearbox |
Non-Patent Citations (2)
| Title |
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| 汪安民等: "《TMS320C674xDSP应用开发》", 31 March 2012, 北京航空航天大学出版社 * |
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Application publication date: 20180831 |