CN108494299A - A kind of disc record machine automatic stable circuit - Google Patents
A kind of disc record machine automatic stable circuit Download PDFInfo
- Publication number
- CN108494299A CN108494299A CN201810349199.7A CN201810349199A CN108494299A CN 108494299 A CN108494299 A CN 108494299A CN 201810349199 A CN201810349199 A CN 201810349199A CN 108494299 A CN108494299 A CN 108494299A
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- CN
- China
- Prior art keywords
- circuit
- control
- unit
- waveform shaping
- driver
- Prior art date
- 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
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P7/00—Arrangements for regulating or controlling the speed or torque of electric DC motors
- H02P7/06—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current
- H02P7/18—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power
- H02P7/24—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices
- H02P7/28—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices
- H02P7/285—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices controlling armature supply only
- H02P7/29—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices controlling armature supply only using pulse modulation
- H02P7/2913—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual dc dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices controlling armature supply only using pulse modulation whereby the speed is regulated by measuring the motor speed and comparing it with a given physical value
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B19/00—Driving, starting, stopping record carriers not specifically of filamentary or web form, or of supports therefor; Control thereof; Control of operating function ; Driving both disc and head
- G11B19/20—Driving; Starting; Stopping; Control thereof
- G11B19/28—Speed controlling, regulating, or indicating
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Direct Current Motors (AREA)
Abstract
The invention discloses a kind of disc record machine automatic stable circuit, including optocoupler detection circuit, waveform shaping circuit, control circuit and driving circuit, the optocoupler detection circuit connects the waveform shaping circuit and pulse signal is sent to waveform shaping circuit；The waveform shaping circuit connects the control circuit, and the pulse signal that optocoupler detection circuit conveys is filtered and shaping by the waveform shaping circuit, then is exported to control circuit；The control circuit connects the driving circuit, and the control circuit is stored with reference frequency information, and the pulse signal of itself and waveform shaping circuit output is carried out analysis comparison, the difference of the two is obtained and sends out control instruction to driving circuit according to difference；The driving circuit controls disc machine according to the instruction of control circuit.The beneficial effects of the present invention are by control circuit, can automatic modifying factor balata belt aging and carbon brush abrasion and caused by rotation speed change phenomenon.
Description
Technical field
The present invention relates to a kind of speed circuit more particularly to a kind of disc record machine automatic stable circuits.
Background technology
Currently, phonograph require disc on disc record even angle rate rotate, speed and tremble pendulum be phonograph important performance assessment criteria, such as
Fruit rotary speed unstabilization will directly affect sound quality quality surely.Common phonograph is generally mainly by direct-current brush motor, belt, turntable and pickup
Device forms.Multiple stations need to be arranged to be monitored adjustment to speed when plant produced, cause low production efficiency, production cost high
The problems such as, and consistency is poor.In addition as time go on, balata belt there is also aging, the carbon of direct-current brush motor
Existing wear phenomenon is brushed out, such rotating speed can increasingly change, and audio is also and then deteriorated.
Moreover, general phonograph does not have rotating speed self-checking circuit, to ensure that rotary speed precision needs to consider following factor：Need several works
The monitoring adjustment repeatedly manually of people's multistation causes low production efficiency, and production cost is high and rotating speed is not still accurate；Balata belt is easily old
Change, rotating speed can also change because of the aging of belt；Common phonograph generally uses brush motor, carbon brush to also wear out and cause rotating speed
Variation.
Invention content
For overcome the deficiencies in the prior art, the present invention uses intelligent measurement speed circuit, can overcome above-mentioned ask very well
Topic.
A kind of disc record machine automatic stable circuit, including optocoupler detection circuit, waveform shaping circuit, control circuit and driving electricity
Road；
The optocoupler detection circuit, waveform shaping circuit, control circuit and driving circuit are sequentially connected electrically, the driving electricity
The output end on road connects the input terminal of the optocoupler detection circuit；
Collected disc machine rotational speed pulse signal is sent to waveform shaping circuit by the optocoupler detection circuit；
The pulse signal that optocoupler detection circuit is sent is filtered and shaping by the waveform shaping circuit, then is exported to control
Circuit processed；
The control circuit connects the driving circuit, the pulse signal that the control circuit exports waveform shaping circuit
Analysis comparison is carried out with pre-stored frequency information, control instruction is sent out to driving circuit according to comparison result；The driving
Circuit controls the rotation of disc machine according to the instruction of control circuit.
Further, the optocoupler detection circuit includes photoelectrical coupler and decoupling unit, the output of the decoupling unit
The photoelectrical coupler input terminal of connection, the decoupling unit is held to be used to eliminate the common mode phenomenon of photoelectrical coupler.
Further, the waveform shaping circuit includes filter unit and shaping unit, the input terminal of the filter unit
The output end of photoelectric coupling circuit is connected, the filter unit output end is connect with shaping unit input terminal.
Further, the control circuit includes control chip, and the control chip is equipped with PWM units, the control core
The output end of the signal input part connection shaping unit of piece, the output end of the PWM units connect driving circuit.
Further, the PWM units include the first duty ratio pin and the second duty ratio pin, first duty ratio
Pin and the second duty ratio pin are used to control the current direction of driving circuit.
Further, the driving circuit include the first driver, the second driver and motor control unit, described first
Driver connect PWM units with the input terminal of the second driver, and first driver is connect with the output end of the second driver
Motor control unit, the motor control unit connect optocoupler detection circuit.
Further, first driver input terminal connect the first duty ratio pin, second driver it is defeated
Enter the second duty ratio pin of end connection, the driving unit controls motor control unit according to the PWM wave that PWM units export.
Further, the motor control unit includes first switch pipe and second switch pipe, the first switch pipe with
The control terminal of second switch pipe connects the first driver, and the high level end of the first switch pipe is connect with the first duty ratio pin
In test point, the low level end of the first switch pipe is connected to the first output point with the high level end of second switch pipe.
Further, the motor control unit further includes third switching tube and the 4th switching tube, the third switching tube
It connect the second driver with the control terminal of the 4th switching tube, the high level end connecting detection point of the third switching tube, described
The low level end of three switching tubes and the high level end of the 4th switching tube are connected to the second output point.
Further, the motor control unit further includes motor, anode the first output point of connection of the motor, described
The cathode of motor connects the second output point.
Compared with prior art, the beneficial effects of the present invention are：
(1) by control circuit, can automatic modifying factor balata belt aging and carbon brush abrasion and caused by rotation speed change it is existing
As；
(2) exempt to debug motor, production efficiency can be improved and reduce production cost so that the consistency of rotating speed is good and accurate
Degree is high；
(3) rotating speed can also be adjusted according to personal preference, provide personalized appreciation music demand.
Description of the drawings
Fig. 1 is disc record machine automatic stable circuit structure block diagram of the present invention；
Fig. 2 is optocoupler detection circuit figure of the present invention；
Fig. 3 is waveform shaping circuit figure of the present invention；
Fig. 4 is electric operation control circuit figure of the present invention；
Fig. 5 is present invention driver circuit figure.
Specific implementation mode
In the following, in conjunction with attached drawing and specific implementation mode, the present invention is described further, it should be noted that not
Under the premise of conflicting, new implementation can be formed between various embodiments described below or between each technical characteristic in any combination
Example.
A kind of disc record machine automatic stable circuit as shown in Figure 1, including optocoupler detection circuit 1, waveform shaping circuit 2, control
Circuit 3 and driving circuit 4.
Optocoupler detection circuit 1, waveform shaping circuit 2, control circuit 3 and driving circuit 4 are sequentially connected electrically, driving circuit 4
Output end connection optocoupler detection circuit 1 input terminal；Optocoupler detection circuit 1 sends out collected disc machine rotational speed pulse signal
Give waveform shaping circuit 2；The pulse signal that optocoupler detection circuit 1 is sent is filtered and shaping by waveform shaping circuit 2, then
It exports to control circuit 3；Control circuit 3 connects driving circuit 4, the pulse signal that control circuit 3 exports waveform shaping circuit 2
Analysis comparison is carried out with pre-stored frequency information, control instruction is sent out to driving circuit 4 according to comparison result；Driving circuit
4 control the rotation of disc machine according to the instruction of control circuit 3.
As preferred embodiment, as shown in Fig. 2, optocoupler detection circuit 1 includes by light emitting diode D1 and triode
The photoelectrical coupler PC1 of Q1 compositions and decoupling unit decouple the input terminal of the output end connection photoelectrical coupler PC1 of unit, light
The input terminal of the output end connection waveform shaping circuit 2 of electric coupler PC1, optocoupler detection circuit 1 is by the arteries and veins of the rotating speed detected
Signal is rushed to export to waveform shaping circuit 2.
In the present embodiment, decoupling unit includes first resistor R1 and the first capacitance C1, and the one end first resistor R1 connects the
One high level VCC, the first resistor R1 other ends connect the input terminal of the first capacitance C1 and photoelectrical coupler PC1, the first capacitance C1
The other end is grounded.Decoupling unit can be eliminated to photoelectrical coupler PC1 common-mode influences so that photoelectrical coupler PC1 interference free performances
By force.
As preferred embodiment, as shown in figure 3, waveform shaping circuit 2 includes filter unit and shaping unit, filtering
The input terminal of unit is equipped with the second resistance R2 for being connected to the first high level VCC, and the input terminal of filter unit connects photoelectric coupling
The output end of device PC1, the input terminal of the output end connection shaping unit of filter unit, the output end connection control electricity of shaping unit
The pulse signal that optocoupler detection circuit 1 exports is filtered and shaping by the input terminal on road 3, waveform shaping circuit 2, then export to
Control circuit 3.
In the present embodiment, filter unit is equipped with 3rd resistor R3 and the second capacitance C2,3rd resistor R3 and the second capacitance
C2 is connected in parallel, and filter unit is connected with reversed ground connection diode D2, diode D2 for protecting shaping unit.Shaping unit is
The output end of the ground level connection filter unit of second triode Q2, the second triode Q2, the emitter ground connection of the second triode Q2,
The collector of second triode Q2 connects control circuit 3, and the collector of the second triode Q2 also passes through the 4th resistance R4 connections the
One high level VCC.
As preferred embodiment chip is controlled as shown in figure 4, control circuit 3 includes control chip U1 and crystal oscillator Y1
The output end of the signal input part connection shaping unit of U1, crystal oscillator Y1 are connected to the phase-locked loop module of control chip, control chip
U1 is equipped with PWM units, and PWM units connect the input terminal of driving circuit 4.
In the present embodiment, PWM units include the first duty ratio pin P1 and the second duty ratio pin P2, the first duty ratio
Pin P1 and the second duty ratio pin P2 is used to control the current direction of driving circuit 4.
As preferred embodiment, as shown in figure 5, driving circuit 4 include the first driver G1, the second driver G2 and
Motor control unit, the first driver G1 connect PWM units, the first driver G1 and second with the input terminal of the second driver G2
The output end of driver G2 connects motor control unit, and motor control unit connects optocoupler detection circuit 1, driving unit according to
The PWM wave of PWM units output controls motor control unit.
In the present embodiment, motor control unit is equipped with first switch pipe PM1 and second switch pipe PM2, first switch pipe
PM1 connect the first driver G1, high level end and the first duty of first switch pipe PM1 with the control terminal of second switch pipe PM2
It is connected to test point A1 than pin P1, the low level end of first switch pipe PM1 and the high level end of second switch pipe PM2 are connected to
First output point A2.
In the present embodiment, motor control unit is equipped with third switching tube PM3 and the 4th switching tube PM4, third switching tube
PM3 connect the second driver G2, the high level end connecting detection point of third switching tube PM3 with the control terminal of the 4th switching tube PM4
A1, the low level end of third switching tube PM3 are connected to the second output point A3 with the high level end of the 4th switching tube PM4.
In the present embodiment, motor control unit is additionally provided with motor M and the ground resistance R7 for protecting circuit, motor M
Anode the first output point A2 of connection, the cathode of motor M connects the second output point A3, and the other end of ground resistance R7 is connected to inspection
Measuring point A1.When the first duty ratio pin P1 conductings, the first driver G1 has high level, to make the first output point A2 conductings,
Motor M is rotated forward；When the second duty ratio pin P2 conductings, the second driver G2 has high level, to make the second output point
When A3 is connected, motor M is rotated backward.
In the present embodiment, it is additionally provided with touch-switch K1 and indicator light D3 on control chip U1, touch-switch K1 is for controlling
The break-make of coremaking piece U1 control disc machines, functions of the indicator light D3 for disc machine indicate.
In the present embodiment, the generation process of the reference frequency (24MHZ) of control chip U1 is：Control the inside of chip U1
Quartz crystal frequency 32768HZ first generates base frequency oscillation, then can be protected in this way to 24MHZ through phase locked-loop unit and crystal oscillator Y1 frequencys multiplication
Card control chip U1 detection actual speed F2 and the Pr of output control have sufficiently high precision.Control the exportable 16Bit of chip U1
PWM, Bit is higher, and resolution ratio is higher, control rotating speed it is finer.
Preferably, controlling the operating procedure that chip U1 is analyzed and determined is：
S1：The rotating speed of user preset is inputed into control circuit 3 and is assigned a value of F1, then data analysis will be passed through and filtered with shaping
Rotating speed after wave is set as F2, calculates the difference F=F1-F2 of the two；
S2：Control circuit 3 is according to the positive negative justification duty ratio Pr of F values, if difference F is positive number, the duty ratio Pr of PWM increases
Add, actual speed F2 also increases；If if difference F is negative, duty ratio Pr reduces, and actual speed F2 also reduces；If difference F is
0, then duty ratio Pr is constant, and actual speed F2 is also constant；
S3：If the duty ratio Pr after adjustment increases, the first duty ratio pin P1 conductings, to the first control terminal control of conducting
Device G1 processed, then first switch pipe is connected with the high level end of second switch pipe so that motor M Positive works；
S4：If the duty ratio Pr after adjustment is reduced, third duty ratio pin P3 conductings, to the second control terminal control of conducting
Device G2 processed, then third switching tube P3 is connected with the high level end of the 4th switching tube P4 so that motor M Positive works；
S5：Rotating speed after adjustment is sent to optocoupler detection circuit 1 by motor M again, to realize automatic speed regulation.
Preferably, when adjusting actual speed F2, if difference F is very big beyond preset value F1, duty ratio Pr carries out the sudden turn of events,
Very short time can be achieved in this way and reach speed stabilizing purpose.If reduce actual speed F2, brake auxiliary work(is called with control circuit 4
Can, reverse signal is exported by the second duty ratio pin P2, allows motor M reversions and drastically reduction of speed or even completely stopping.By above-mentioned
Automatic stable circuit, you can realize from motion tracking, speed governing until speed stabilizing purpose.
The present invention by control circuit can automatic modifying factor balata belt aging and by carbon brush abrasion caused by rotation speed change
Phenomenon；Exempt to debug motor, production efficiency can be improved and reduce production cost so that the consistency of rotating speed is good and precision is high；
Rotating speed can also be adjusted according to personal preference, provide personalized appreciation music demand.
The above embodiment is only the preferred embodiment of the present invention, and the scope of protection of the present invention is not limited thereto,
The variation and replacement for any unsubstantiality that those skilled in the art is done on the basis of the present invention belong to institute of the present invention
Claimed range.
Claims (10)
1. a kind of disc record machine automatic stable circuit, including optocoupler detection circuit, waveform shaping circuit, control circuit and driving electricity
Road, which is characterized in that
The optocoupler detection circuit, waveform shaping circuit, control circuit and driving circuit are sequentially connected electrically, the driving circuit
Output end connects the input terminal of the optocoupler detection circuit；
Collected disc machine rotational speed pulse signal is sent to waveform shaping circuit by the optocoupler detection circuit；
The pulse signal that optocoupler detection circuit is sent is filtered and shaping by the waveform shaping circuit, then is exported and given control electricity
Road；
The control circuit connects the driving circuit, the pulse signal that waveform shaping circuit export by the control circuit in advance
The frequency information first stored carries out analysis comparison, and control instruction is sent out to driving circuit according to comparison result；The driving circuit
The rotation of disc machine is controlled according to the instruction of control circuit.
2. disc record machine automatic stable circuit according to claim 1, which is characterized in that the optocoupler detection circuit includes photoelectricity
Coupler and decoupling unit, the photoelectrical coupler input terminal of the output end connection of the decoupling unit, the decoupling unit are used for
Eliminate the common mode phenomenon of photoelectrical coupler.
3. disc record machine automatic stable circuit according to claim 1, which is characterized in that the waveform shaping circuit includes filtering
Unit and shaping unit, the output end of the input terminal connection photoelectric coupling circuit of the filter unit, the filter unit output
End is connect with shaping unit input terminal.
4. disc record machine automatic stable circuit according to claim 3, which is characterized in that the control circuit includes control core
Piece, the control chip are equipped with PWM units, and the output end of the signal input part connection shaping unit of the control chip is described
The output end of PWM units connects driving circuit.
5. disc record machine automatic stable circuit according to claim 4, which is characterized in that the PWM units include the first duty
Than pin and the second duty ratio pin, the electricity of the first duty ratio pin and the second duty ratio pin for controlling driving circuit
Stream flow direction.
6. disc record machine automatic stable circuit according to claim 5, which is characterized in that the driving circuit includes the first driving
Device, the second driver and motor control unit, first driver connect PWM units, institute with the input terminal of the second driver
It states the first driver and connect motor control unit, the motor control unit connection optocoupler detection with the output end of the second driver
Circuit.
7. disc record machine automatic stable circuit according to claim 6, which is characterized in that the input terminal of first driver connects
The first duty ratio pin is connect, the input terminal of second driver connects the second duty ratio pin, and the driving unit is according to PWM
The PWM wave of unit output controls motor control unit.
8. disc record machine automatic stable circuit according to claim 6, which is characterized in that the motor control unit includes first
Switching tube and second switch pipe, the first switch pipe connect the first driver with the control terminal of second switch pipe, and described first
The high level end of switching tube is connected to test point with the first duty ratio pin, and the low level end of the first switch pipe is opened with second
The high level end for closing pipe is connected to the first output point.
9. disc record machine automatic stable circuit according to claim 8, which is characterized in that the motor control unit further includes
Three switching tubes and the 4th switching tube, the third switching tube connect the second driver with the control terminal of the 4th switching tube, and described
The high level end connecting detection point of three switching tubes, the low level end of the third switching tube connect with the high level end of the 4th switching tube
It is connected to the second output point.
10. disc record machine automatic stable circuit according to claim 8, which is characterized in that the motor control unit further includes
Motor, anode the first output point of connection of the motor, the cathode of the motor connect the second output point.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810349199.7A CN108494299A (en) | 2018-04-18 | 2018-04-18 | A kind of disc record machine automatic stable circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810349199.7A CN108494299A (en) | 2018-04-18 | 2018-04-18 | A kind of disc record machine automatic stable circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108494299A true CN108494299A (en) | 2018-09-04 |
Family
ID=63312623
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810349199.7A Pending CN108494299A (en) | 2018-04-18 | 2018-04-18 | A kind of disc record machine automatic stable circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108494299A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07284295A (en) * | 1993-12-09 | 1995-10-27 | Samsung Heavy Ind Co Ltd | Dynamic braking controller of electric motor |
| JP2003037993A (en) * | 2001-07-25 | 2003-02-07 | Nikon Corp | Actuator driving circuit stage device and exposure system |
| TW200518438A (en) * | 2003-11-19 | 2005-06-01 | Delta Electronics Inc | Motor control circuit |
| CN204089658U (en) * | 2014-10-21 | 2015-01-07 | 安徽理工大学 | Based on the Switched Reluctance Motor of DSP |
| CN208522671U (en) * | 2018-04-18 | 2019-02-19 | 深圳市新芯瑞科技有限公司 | A kind of disc record machine automatic stable circuit |
-
2018
- 2018-04-18 CN CN201810349199.7A patent/CN108494299A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07284295A (en) * | 1993-12-09 | 1995-10-27 | Samsung Heavy Ind Co Ltd | Dynamic braking controller of electric motor |
| JP2003037993A (en) * | 2001-07-25 | 2003-02-07 | Nikon Corp | Actuator driving circuit stage device and exposure system |
| TW200518438A (en) * | 2003-11-19 | 2005-06-01 | Delta Electronics Inc | Motor control circuit |
| CN204089658U (en) * | 2014-10-21 | 2015-01-07 | 安徽理工大学 | Based on the Switched Reluctance Motor of DSP |
| CN208522671U (en) * | 2018-04-18 | 2019-02-19 | 深圳市新芯瑞科技有限公司 | A kind of disc record machine automatic stable circuit |
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