CN201804070U - Polarity detecting system for magnetic head voice coil - Google Patents
Polarity detecting system for magnetic head voice coil Download PDFInfo
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- CN201804070U CN201804070U CN 201020294318 CN201020294318U CN201804070U CN 201804070 U CN201804070 U CN 201804070U CN 201020294318 CN201020294318 CN 201020294318 CN 201020294318 U CN201020294318 U CN 201020294318U CN 201804070 U CN201804070 U CN 201804070U
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- magnetic head
- polarity
- loudspeaker voice
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Abstract
The utility model relates to a polarity detecting system for a magnetic head voice coil, which comprises a first electromagnetism electric conversion module, a signal amplifying circuit, a signal comparison circuit and a discrimination module, wherein the first electromagnetism electric conversion module is used for converting a current signal of a first magnetic head voice coil into a polarity electric signal of the first magnetic head voice coil; the signal amplifying circuit is used for amplifying the polarity electric signal; and the discrimination module is used for comparing a forward signal of the amplified polarity electric signal with a backward signal of the amplified polarity electric signal, generating a comparison signal and discriminating the polarity of the first magnetic head voice coil according to the comparison signal. The polarity detecting system for the magnetic head voice coil is designed by adopting an electronic circuit, is convenient for use, adopts a simple detection method, has high sensitivity and can carry out monitoring reliably.
Description
Technical field
The utility model relates to detection range, more particularly, relates to a kind of magnetic head voice coil loudspeaker voice coil polarity detection system that is used for the magnetic head product.
Background technology
Along with the develop rapidly of disk storage technology, magnetic head is as one of core component of disk, and the detection of its quality of production is also important further, especially for being used for server magnetic head product.The magnetic head voice coil loudspeaker voice coil is the important component part of magnetic head, it is detected accurately help enhancing productivity, and also can promote the improvement of production aspect simultaneously.
The detection system that is applied to the magnetic head voice coil loudspeaker voice coil at present mainly adopts Hall element aspect polarity, require Hall element to have higher sensitivity in actual applications, but is to use inconvenience, detection method complicated and cost an arm and a leg.
The utility model content
The technical problems to be solved in the utility model is, magnetic head voice coil loudspeaker voice coil polarity detection system at prior art uses inconvenience, detection method is complicated and expensive defective, provide a kind of employing electronic circuit to design, the convenient application, detection method is simple, have very high sensitivity, can implement the magnetic head voice coil loudspeaker voice coil polarity detection system of monitoring reliably.
The technical scheme that its technical matters that solves the utility model adopts is: construct a kind of magnetic head voice coil loudspeaker voice coil polarity detection system, wherein, first electromagnetism electricity modular converter that comprises the polarity electric signal that will be converted to the described first magnetic head voice coil loudspeaker voice coil by the current signal of the first magnetic head voice coil loudspeaker voice coil, described polarity electric signal is carried out the amplifying signal amplifying circuit, the forward signal of the polarity electric signal after amplifying and the reverse signal of the polarity electric signal after the amplification are compared, produce the signal comparator circuit of comparison signal and the discrimination module of the described first magnetic head voice coil loudspeaker voice coil polarity being differentiated according to described comparison signal.
In magnetic head voice coil loudspeaker voice coil polarity detection system described in the utility model, described first electromagnetism electricity modular converter comprises the inductive coil that the current signal by the described first magnetic head voice coil loudspeaker voice coil is converted to the electromagnetic conversion unit of corresponding magnetic signal and described magnetic signal is converted to corresponding polarity electric signal.
In magnetic head voice coil loudspeaker voice coil polarity detection system described in the utility model, described signal amplification circuit comprises forward amplifying circuit that the forward signal of described polarity electric signal is amplified and the reverse amplification circuit that the reverse signal of described polarity electric signal is amplified.
In magnetic head voice coil loudspeaker voice coil polarity detection system described in the utility model, described signal amplification circuit also comprises and draws on the forward signal of described polarity electric signal carried out and/or the reverse signal of described polarity electric signal is carried out drop-down trimming circuit.
In magnetic head voice coil loudspeaker voice coil polarity detection system described in the utility model, described signal amplification circuit also comprise to the forward signal of described polarity electric signal carry out drop-down and/or the reverse signal of described polarity electric signal carried out on the trimming circuit that draws.
In magnetic head voice coil loudspeaker voice coil polarity detection system described in the utility model, described signal amplification circuit also comprises the amplification holding circuit that is used for protecting forward amplifying circuit and reverse amplification circuit.
In magnetic head voice coil loudspeaker voice coil polarity detection system described in the utility model, described forward amplifying circuit and described reverse amplification circuit are the differential amplifier circuit of one-level at least.
In magnetic head voice coil loudspeaker voice coil polarity detection system described in the utility model, described magnetic head voice coil loudspeaker voice coil polarity detection system also comprises the current signal by the second magnetic head voice coil loudspeaker voice coil is converted to second electromagnetism electricity modular converter of polarity electric signal of the described second magnetic head voice coil loudspeaker voice coil and the station handover module that described first electromagnetism electricity modular converter and described second electromagnetism electricity modular converter are switched.
In magnetic head voice coil loudspeaker voice coil polarity detection system described in the utility model, described first electromagnetism electricity modular converter is connected with described signal amplification circuit by shielding line with described second electromagnetism electricity modular converter.
Implement magnetic head voice coil loudspeaker voice coil polarity detection system of the present utility model, have following beneficial effect: this magnetic head voice coil loudspeaker voice coil polarity test system adopts electronic circuit to design, the convenient application, and detection method is simple, has very high sensitivity, can implement monitoring reliably.
Can well be the polarity electric signal relevant with the magnetic head voice coil loudspeaker voice coil by electromagnetic conversion with the electrical signal conversion by the magnetic head voice coil loudspeaker voice coil with the magnetoelectricity conversion.Because the polarity electric signal that magnetic signal produces is very faint, can well realize that by processing and amplifying the signal of back compares.Trimming circuit has well been regulated the voltage difference of forward signal and reverse signal, thereby has guaranteed the sensitivity relatively of back signal.Amplify holding circuit the amplitude limit effect has been played in the input of forward amplifying circuit and reverse amplification circuit, protected the trouble free service of amplifier.The use of multistage differential amplifier circuit has been widened the useful signal pulse width and is convenient to software test and distinguish disturbs.Station handover module and a plurality of electromagnetism electricity modular converter the switching that has realized left and right sides station is set, improved work efficiency.Shielding line the antijamming capability that has improved circuit is set.
Description of drawings
The utility model is described in further detail below in conjunction with drawings and Examples, in the accompanying drawing:
Fig. 1 is the structural representation of first preferred embodiment of the utility model magnetic head voice coil loudspeaker voice coil polarity detection system;
Fig. 2 is the structural representation of second preferred embodiment of the utility model magnetic head voice coil loudspeaker voice coil polarity detection system;
Fig. 3 is the structural representation of the 3rd preferred embodiment of the utility model magnetic head voice coil loudspeaker voice coil polarity detection system;
Fig. 4 is the structural representation of the 4th preferred embodiment of the utility model magnetic head voice coil loudspeaker voice coil polarity detection system;
Fig. 5 is the structural representation of the 5th preferred embodiment of the utility model magnetic head voice coil loudspeaker voice coil polarity detection system;
Fig. 6 is the circuit diagram of the preferred embodiment of the utility model magnetic head voice coil loudspeaker voice coil polarity detection system;
Fig. 7 A is the waveform sequential chart (when the magnetic head voice coil loudspeaker voice coil is just connecing) of the comparison module of the utility model magnetic head voice coil loudspeaker voice coil polarity detection system;
Fig. 7 B is the waveform sequential chart (during the reversal connection of magnetic head voice coil loudspeaker voice coil) of the comparison module of the utility model magnetic head voice coil loudspeaker voice coil polarity detection system;
Fig. 8 is the detection output waveform figure (when the magnetic head voice coil loudspeaker voice coil is just connecing) of the comparison module of the utility model magnetic head voice coil loudspeaker voice coil polarity detection system.
Embodiment
Below in conjunction with diagram, preferred embodiment of the present utility model is described in detail.
Shown in Fig. 1,6, in first preferred embodiment of magnetic head voice coil loudspeaker voice coil polarity detection system of the present utility model, described magnetic head voice coil loudspeaker voice coil polarity detection system comprises first electromagnetism electricity modular converter 1, signal amplification circuit 2, signal comparator circuit 3 and discrimination module 4.First electromagnetism electricity modular converter 1 is used for the current signal by the first magnetic head voice coil loudspeaker voice coil is converted to the polarity electric signal of the first magnetic head voice coil loudspeaker voice coil, signal amplification circuit 2 is used for described polarity electric signal is amplified, signal comparator circuit 3 is used for the forward signal of the polarity electric signal after amplifying and the reverse signal of the polarity electric signal after amplifying compares, produces comparison signal, and discrimination module 4 is used for according to described comparison signal the described first magnetic head voice coil loudspeaker voice coil polarity being differentiated.This magnetic head voice coil loudspeaker voice coil polarity detection system when work, the connector of magnetic head head heap is introduced in the design system, and the first magnetic head voice coil loudspeaker voice coil of control head heap thus.When giving the certain electric current of being piled by gauge head of the first magnetic head voice coil loudspeaker voice coil (100mA), first electromagnetism electricity modular converter 1 can be converted to the corresponding polarity electric signal of the first magnetic head voice coil loudspeaker voice coil by the electromagnetism electricity with it; This polarity electric signal is very faint, in order to detect reliably, this electric signal is input to signal amplification circuit 2, through amplifying, exports discrimination module 4 to through signal comparator circuit 3 again.In discrimination module 4, judge according to the signal waveform width of gathering whether the first magnetic head voice coil loudspeaker voice coil connects correctly.This magnetic head voice coil loudspeaker voice coil polarity test system adopts electronic circuit to design, the convenient application, and detection method is simple, has very high sensitivity, can implement monitoring reliably.
In the preferred embodiment of magnetic head voice coil loudspeaker voice coil polarity detection system of the present utility model, first electromagnetism electricity modular converter 1 comprises electromagnetic conversion unit and inductive coil.Electromagnetic conversion unit is used for the current signal by the first magnetic head voice coil loudspeaker voice coil is converted to corresponding magnetic signal, and inductive coil is used for described magnetic signal is converted to corresponding polarity electric signal.During this first electromagnetism electricity modular converter work, when giving the certain electric current of being piled by gauge head of the first magnetic head voice coil loudspeaker voice coil (100mA), electromagnetic conversion unit can produce corresponding magnetic signal, and inductive coil will produce the corresponding polarity electric signal of instantaneous and described magnetic head voice coil loudspeaker voice coil polarity after sensing this magnetic signal.By the electromagnetic conversion of electromagnetic conversion unit and the magnetoelectricity conversion of inductive coil can well be and the corresponding polarity electric signal of magnetic head voice coil loudspeaker voice coil to make things convenient for the measurement of back operation with the electrical signal conversion by the magnetic head voice coil loudspeaker voice coil.
Shown in Fig. 2,6, in second preferred embodiment of magnetic head voice coil loudspeaker voice coil polarity detection system of the present utility model, signal amplification circuit 2 comprises forward amplifying circuit 21 and reverse amplification circuit 22.Forward amplifying circuit 21 is used for the forward signal of described polarity electric signal is amplified, and reverse amplification circuit 22 is used for the reverse signal of described polarity electric signal is amplified.The principle of work of this magnetic head voice coil loudspeaker voice coil polarity detection system produces comparative result for by the forward signal of more described polarity electric signal and the reverse signal of described polarity electric signal, judges according to the difference of comparative result whether magnetic head voice coil loudspeaker voice coil polarity connects correctly.Because the polarity electric signal that inductive coil produces is very faint, amplify so need carry out signal earlier, just can be input to signal comparator circuit 3 and carry out the comparison of voltage.
Shown in Fig. 3,6, in the 3rd preferred embodiment of magnetic head voice coil loudspeaker voice coil polarity detection system of the present utility model, signal amplification circuit 2 also comprises trimming circuit 23, trimming circuit 23 be used for to the forward signal of described polarity electric signal carry out drop-down and/or the reverse signal of described polarity electric signal carried out on draw, to the forward signal of described polarity electric signal carry out drop-down and/or the reverse signal of described polarity electric signal carried out on draw.Make when the magnetic head voice coil loudspeaker voice coil does not have the signal input, certain voltage difference appears in two input ends of signal comparator circuit 3, make that result relatively is more accurate, can well adjust the sensitivity of comparison, when sensitivity is too low can by on draw or the drop-down voltage difference that makes increases the precision with the measurement that increases signal comparator circuit 3, when the time pulse signal of discrimination module 4 output is too short, can be by reducing the difficulty of voltage difference with the judgement that reduces discrimination module 4.As shown in Figure 6, trimming circuit 23 is the adjustable pull down resistor that the output terminal of forward amplifying circuit 22 connects, and also can connect a mode such as pull-up resistor by the output terminal at reverse amplification circuit 22 certainly and reach same purpose.Trimming circuit 23 has well been regulated the voltage difference of forward signal and reverse signal, thereby has guaranteed the sensitivity of back signal comparator circuit 3.
Shown in Fig. 4,6, in the 4th preferred embodiment of magnetic head voice coil loudspeaker voice coil polarity detection system of the present utility model, signal amplification circuit 2 also comprises amplification holding circuit 24.Amplify the amplifier that holding circuit 24 is used for protecting forward amplifying circuit 21 and reverse amplification circuit 22.As shown in Figure 6, amplifying holding circuit 24 is the diode of D18, two reverse parallel connections of D21.This amplifies holding circuit can play the effect of amplitude limit with the input voltage clamper of signal amplification circuit 2 in 0.6 volt, guaranteed the trouble free service of the amplifier in the signal amplification circuit 2.
In the preferred embodiment of magnetic head voice coil loudspeaker voice coil polarity detection system of the present utility model, forward amplifying circuit 21 and reverse amplification circuit 22 are the differential amplifier circuit of one-level at least.Adopt differential amplifier circuit effective recognition to get rid of extraneous undesired signal.Can also adopt multistage differential amplifier circuit that the polarity electric signal is carried out multistage amplification, increase the pulse signal width of discrimination module 4 outputs, reduce the difficulty of the judgement of discrimination module 4.Shown in figure six, the polarity electric signal amplifies through two-stage, and signal is exaggerated 2000 times, exports discrimination module 4 to through signal comparator circuit 3 again and judges.The use of multistage differential amplifier circuit has been widened the useful signal pulse width and is convenient to software test and distinguish disturbs.
Shown in Fig. 5,6, in the 5th preferred embodiment of magnetic head voice coil loudspeaker voice coil polarity detection system of the present utility model, described magnetic head voice coil loudspeaker voice coil polarity detection system also comprises second electromagnetism electricity modular converter and station handover module 5.Second electromagnetism electricity modular converter is used for the current signal by the second magnetic head voice coil loudspeaker voice coil is converted to the polarity electric signal of the described second magnetic head voice coil loudspeaker voice coil, and station handover module 5 is used for first electromagnetism electricity modular converter 1 and second electromagnetism electricity modular converter are switched.As described in Figure 6, the principle of work of second electromagnetism electricity modular converter is identical with first electromagnetism electricity modular converter 1.Station handover module 5 comprises a triode Q15, carries out the switching of first electromagnetism electricity modular converter 1 and the work of second electromagnetism electricity modular converter by the high-low level of control triode Q15 base stage pin.Owing to the switching that has realized first electromagnetism electricity modular converter 1 and the electric modular converter station of second electromagnetism that is provided with of station handover module and a plurality of electromagnetism electricity modular converter, improved the work efficiency of magnetic head voice coil loudspeaker voice coil polarity detection system greatly.
In the preferred embodiment of magnetic head voice coil loudspeaker voice coil polarity detection system of the present utility model, first electromagnetism electricity modular converter 1 is connected with signal amplification circuit 2 by shielding line with described second electromagnetism electricity modular converter.Shielding line the antijamming capability that has improved circuit is set, make that the polarity electric signal is more accurate.
The course of work of this magnetic head voice coil loudspeaker voice coil polarity detection system is described below in conjunction with specific embodiment:
Shown in Fig. 7 A and 7B, at first to a magnetic head voice coil loudspeaker voice coil input square signal (TX among the figure), this square signal becomes the waveform of the reverse signal of the waveform of forward signal of the polarity electric signal shown in RX+ among the figure and the polarity electric signal shown in RX-among the figure after through magnetoelectricity magnetic modular converter.Respectively the forward signal of polarity electric signal and the reverse signal of polarity electric signal are amplified through signal amplification circuit 2 then, amplify the back and the forward signal of polarity electric signal is carried out drop-down processing (trimming circuit 23) make the voltage difference of reverse signal of the forward signal of polarity electric signal and polarity electric signal increase precision with the measurement that increases signal comparator circuit 3.Subsequently the forward signal of polarity electric signal is input to 3 pin of signal comparator circuit 3, the reverse signal of polarity electric signal is input to 2 pin of signal comparator circuit 3, the signal of 3 pairs 2 pin of signal comparator circuit and 3 pin is made comparison, when the magnitude of voltage of 3 pin input signals is higher than the magnitude of voltage of 2 pin input, the output high level, otherwise output low level has promptly formed the output waveform (RX among the figure) of signal comparator circuit 3.As can be seen from the figure, when the magnetic head voice coil loudspeaker voice coil correctly connected, the waveform of RX can produce the high level of a 20-90ms after the magnetic head voice coil loudspeaker voice coil is imported square signal; And connecing inverse time when the magnetic head voice coil loudspeaker voice coil, the waveform of RX can produce the high level of a 20-90ms after the magnetic head voice coil loudspeaker voice coil is imported square signal and finished; When the magnetic head voice coil loudspeaker voice coil does not have the signal input, then not output of signal comparator circuit 3, expression magnetic head voice-coil open or short circuit.Discrimination module 4 judges with width whether polarity is connected correctly the magnetic head voice coil loudspeaker voice coil by the time of differentiating the high level generation.
Fig. 8 is the detection output waveform figure of the discrimination module of the utility model magnetic head voice coil loudspeaker voice coil polarity detection system, access and disconnection by software control magnetic head voice coil loudspeaker voice coil, and after the magnetic head voice coil loudspeaker voice coil inserts, obtain the instantaneous value of signal comparator circuit 3 output terminals and be depicted as curve, Fig. 8 is the output waveform figure of the correct signal comparator circuit 3 that connects of magnetic head voice coil loudspeaker voice coil, this figure shows that this pulse signal kept the time of nearly 60ms, and when appearing at the circuit emission, judge corresponding tested magnetic head voice coil loudspeaker voice coil polarity normal (positive pole) thus.
The above only is embodiment of the present utility model; be not so limit claim of the present utility model; every equivalent structure transformation that utilizes the utility model instructions and accompanying drawing content to be done; or directly or indirectly be used in other relevant technical fields, all in like manner be included in the scope of patent protection of the present utility model.
Claims (9)
1. magnetic head voice coil loudspeaker voice coil polarity detection system, it is characterized in that, first electromagnetism electricity modular converter (1) that comprises the polarity electric signal that will be converted to the described first magnetic head voice coil loudspeaker voice coil by the current signal of the first magnetic head voice coil loudspeaker voice coil, described polarity electric signal is carried out amplifying signal amplifying circuit (2), the forward signal of the polarity electric signal after amplifying and the reverse signal of the polarity electric signal after the amplification are compared, produce the signal comparator circuit (3) of comparison signal and the discrimination module of the described first magnetic head voice coil loudspeaker voice coil polarity being differentiated according to described comparison signal (4).
2. magnetic head voice coil loudspeaker voice coil polarity detection system according to claim 1, it is characterized in that described first electromagnetism electricity modular converter (1) comprises the inductive coil that the current signal by the described first magnetic head voice coil loudspeaker voice coil is converted to the electromagnetic conversion unit of corresponding magnetic signal and described magnetic signal is converted to corresponding polarity electric signal.
3. magnetic head voice coil loudspeaker voice coil polarity detection system according to claim 1, it is characterized in that described signal amplification circuit (2) comprises forward amplifying circuit (21) that the forward signal of described polarity electric signal is amplified and the reverse amplification circuit (22) that the reverse signal of described polarity electric signal is amplified.
4. magnetic head voice coil loudspeaker voice coil polarity detection system according to claim 3, it is characterized in that described signal amplification circuit (2) also comprises and draws on the forward signal of described polarity electric signal carried out and/or the reverse signal of described polarity electric signal is carried out drop-down trimming circuit (23).
5. magnetic head voice coil loudspeaker voice coil polarity detection system according to claim 3, it is characterized in that, described signal amplification circuit (2) also comprise to the forward signal of described polarity electric signal carry out drop-down and/or the reverse signal of described polarity electric signal carried out on the trimming circuit (23) that draws.
6. magnetic head voice coil loudspeaker voice coil polarity detection system according to claim 3 is characterized in that, described signal amplification circuit (2) also comprises the amplification holding circuit (24) that is used for protecting forward amplifying circuit (21) and reverse amplification circuit (22).
7. magnetic head voice coil loudspeaker voice coil polarity detection system according to claim 3 is characterized in that, described forward amplifying circuit (21) and described reverse amplification circuit (22) are the differential amplifier circuit of one-level at least.
8. magnetic head voice coil loudspeaker voice coil polarity detection system according to claim 1, it is characterized in that described magnetic head voice coil loudspeaker voice coil polarity detection system also comprises the current signal by the second magnetic head voice coil loudspeaker voice coil is converted to second electromagnetism electricity modular converter of polarity electric signal of the described second magnetic head voice coil loudspeaker voice coil and the station handover module (5) that described first electromagnetism electricity modular converter (1) and the electric modular converter of described second electromagnetism are switched.
9. magnetic head voice coil loudspeaker voice coil polarity detection system according to claim 1 is characterized in that, described first electromagnetism electricity modular converter (1) is connected with described signal amplification circuit (2) by shielding line with described second electromagnetism electricity modular converter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201020294318 CN201804070U (en) | 2010-08-17 | 2010-08-17 | Polarity detecting system for magnetic head voice coil |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201020294318 CN201804070U (en) | 2010-08-17 | 2010-08-17 | Polarity detecting system for magnetic head voice coil |
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| Publication Number | Publication Date |
|---|---|
| CN201804070U true CN201804070U (en) | 2011-04-20 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 201020294318 Expired - Fee Related CN201804070U (en) | 2010-08-17 | 2010-08-17 | Polarity detecting system for magnetic head voice coil |
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| CN (1) | CN201804070U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109068254A (en) * | 2018-07-06 | 2018-12-21 | 郑州大学 | A kind of voice coil polarity test device based on ergonomics in safety |
-
2010
- 2010-08-17 CN CN 201020294318 patent/CN201804070U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109068254A (en) * | 2018-07-06 | 2018-12-21 | 郑州大学 | A kind of voice coil polarity test device based on ergonomics in safety |
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| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20110420 Termination date: 20150817 |
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