CN110044253A - A kind of micro motor and embedded angle measurement unit - Google Patents
A kind of micro motor and embedded angle measurement unit Download PDFInfo
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- CN110044253A CN110044253A CN201910444857.5A CN201910444857A CN110044253A CN 110044253 A CN110044253 A CN 110044253A CN 201910444857 A CN201910444857 A CN 201910444857A CN 110044253 A CN110044253 A CN 110044253A
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- measurement
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- hearth
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/30—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring angles or tapers; for testing the alignment of axes
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Abstract
The present invention discloses a kind of micro motor and embedded angle measurement unit.Embedded angle measurement unit provided by the invention includes: metal upper bed-plate, metal lower bottom base, multiple measurement top electrodes, multiple measurement hearth electrodes, multiple shielding top electrodes and multiple shielding hearth electrodes.Corresponding each measurement top electrode is provided with a measurement hearth electrode, measurement top electrode and measurement hearth electrode form multiple capacitance structures, the rotor rotation of micro motor drives each measurement hearth electrode movement, to change measurement top electrode and measure the capacitance between hearth electrode, the rotational angle of rotor is characterized by the capacitance of real-time change.Multiple shielding top electrodes and multiple shielding hearth electrodes form internal shield, metal upper bed-plate and metal bottom flap form external shielding layer after closing, it is designed using inside and outside two layers of shielding construction, so that embedded angle measurement unit has the ability of stronger shielding external electromagnetic environmental disturbances, influence of the micro motor driving signal to detection while embedded detection is avoided simultaneously.
Description
Technical field
The present invention relates to micro electro mechanical system fields, fill more particularly to a kind of embedded angle measurement for micro motor
It sets.
Background technique
Based on the micro motor of piezo actuator by piezoelectric material creep and it is nonlinear influence, motion profile and displacement
Precision is all relatively low, therefore, it is necessary to implement feedback control to the micro motor based on piezo actuator, so that execution structure be made to obtain
Obtain movement in line.And implementing feedback control or the most important ring of closed-loop control is exactly to the fortune for being performed structure
Dynamic state is accurately monitored.And for Piezo-Micromotor, on the one hand since the dielectric constant of piezoelectric material is very big, cause parasitism
Capacitor is very big, and there are biggish variations for the performance of material in power-up procedures;On the other hand since the structure of electromechanical device is multiple
Miscellaneous, size limitation is serious.Although there is the technology detected using capacitive way to the state of micro motor in the prior art
Scheme, still, inventors have found that due to micro motor rotor be movable member, can not extrinsic motivated signal, pumping signal can only
It is added in sensor side, and the structure is tied without other shieldings again after the unique internal shield of sensor side increases pumping signal
Structure, so that the anti-outside electromagnetic interference of sensor and the ability of internal microactrator driving signal interference are poor.
Summary of the invention
The object of the present invention is to provide a kind of embedded angle measurement units and a kind of micro motor for micro motor, use
Inside and outside two layers of shielding construction design, so that embedded angle measurement unit has the energy of stronger shielding external electromagnetic environmental disturbances
Power, while avoiding influence of the micro motor driving signal to detection while embedded detection.
To achieve the above object, the present invention provides following schemes:
A kind of embedded angle measurement unit for micro motor, the measuring device include: under metal upper bed-plate, metal
Pedestal, multiple measurement top electrodes, multiple measurement hearth electrodes, multiple shielding top electrodes and multiple shielding hearth electrodes;Wherein,
The metal upper bed-plate lid, which is closed, forms closed cavity in the opening portion of the metal lower bottom base, and micro motor is located at described
In cavity;
Multiple shielding top electrodes are on a virtual annulus coaxial with the stator of the micro motor, and correspondence is each
The shielding top electrode is provided with the shielding hearth electrode;
The measurement top electrode, and the shielding hearth electrode are provided with immediately below each shielding hearth electrode
It insulate between the measurement top electrode;
Corresponding each measurement top electrode is provided with the measurement hearth electrode, the measurement top electrode and the survey
Amount hearth electrode forms multiple capacitance structures, and the rotor of the micro motor is able to drive each measurement hearth electrode movement when rotating.
Optionally, the region that the lower surface of the metal upper bed-plate corresponds to each shielding top electrode is provided with bottom silicon,
The shielding top electrode is fixed on the lower surface of the bottom silicon.
Optionally, the first insulating layer is provided between the shielding hearth electrode and the measurement top electrode.
Optionally, the lower surface of the measurement top electrode is provided with second insulating layer.
Optionally, lead titanate piezoelectric ceramics layer is provided between the shielding hearth electrode and the shielding top electrode.
Optionally, the measurement top electrode is metal electrode.
Optionally, the measurement top electrode is gold electrode.
Optionally, the measurement hearth electrode is arranged on the rotor base plate of the micro motor.
A kind of micro motor, the micro motor include the embedded angle measurement unit.
The specific embodiment provided according to the present invention, the invention discloses following technical effects:
Embedded angle measurement unit provided by the invention includes: metal upper bed-plate, metal lower bottom base, multiple measurements top electricity
Pole, multiple measurement hearth electrodes, multiple shielding top electrodes and multiple shielding hearth electrodes.Metal upper bed-plate lid is closed in metal lower bottom base
Opening portion forms closed cavity, and micro motor is within the cavity.Multiple shielding top electrodes are coaxial with the stator of micro motor in one
Virtual annulus on, corresponding each shielding top electrode is provided with the shielding hearth electrode.Each shielding hearth electrode just
Lower section is provided with a measurement top electrode, and shields and insulate between hearth electrode and measurement top electrode.Corresponding each measurement top electricity
Pole is provided with a measurement hearth electrode, and measurement top electrode and measurement hearth electrode form multiple capacitance structures, and the rotor of micro motor turns
It is able to drive each measurement hearth electrode movement when dynamic, to change measurement top electrode and measure the capacitance between hearth electrode, passes through
The rotational angle of the capacitance characterization rotor of real-time change.Multiple shielding top electrodes and multiple shielding hearth electrodes form inner shield
Layer, metal upper bed-plate and metal bottom flap form external shielding layer after closing, and are designed using inside and outside two layers of shielding construction, so that embedded
Formula angle measurement unit has the ability of stronger shielding external electromagnetic environmental disturbances, while avoiding in the same of embedded detection
When, influence of the micro motor driving signal to detection.
Detailed description of the invention
It in order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, below will be to institute in embodiment
Attached drawing to be used is needed to be briefly described, it should be apparent that, the accompanying drawings in the following description is only some implementations of the invention
Example, for those of ordinary skill in the art, without any creative labor, can also be according to these attached drawings
Obtain other attached drawings.
Fig. 1 is a kind of embedded angle measurement unit for micro motor provided in an embodiment of the present invention;
Fig. 2 is the equivalent parameters model of embedded angle measurement unit provided in an embodiment of the present invention;
Fig. 3 is the schematic block circuit diagram provided in an embodiment of the present invention for realizing capacitance detecting.
Specific embodiment
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 description, 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.
The object of the present invention is to provide a kind of embedded angle measurement units and a kind of micro motor for micro motor, use
Inside and outside two layers of shielding construction design, so that embedded angle measurement unit has the energy of stronger shielding external electromagnetic environmental disturbances
Power, while avoiding influence of the micro motor driving signal to detection while embedded detection.
In order to make the foregoing objectives, features and advantages of the present invention clearer and more comprehensible, with reference to the accompanying drawing and specific real
Applying mode, the present invention is described in further detail.
Fig. 1 is a kind of embedded angle measurement unit for micro motor provided in an embodiment of the present invention.As shown in Figure 1,
A kind of embedded angle measurement unit for micro motor, the measuring device include: metal upper bed-plate 8, metal lower bottom base 17,
Multiple measurement top electrodes 5, multiple measurement hearth electrodes 16, multiple shielding top electrodes 1 and multiple shielding hearth electrodes 3.Micro motor includes:
It is used to support the stator bottom silicon 9 of micro motor stator, ground connection is used as the stator lead titanate piezoelectric ceramics of stator driving ground electrode
(PZT) bottom electrode 10 connect the stator PZT top electrodes of stator driving signal for realizing the stator PZT layer 11 of stator function
12, for the frictional layer 13 of connecting stator and rotor structure, by stator driving to the rotor structure 14 of rotation and for fixing
The rotor base plate 15 of rotor structure.
The lid of metal upper bed-plate 8, which is closed, forms closed cavity in the opening portion of the metal lower bottom base 17, and micro motor is located at
In the cavity.The metal upper bed-plate 8 and the metal lower bottom base 17 lid form external shielding layer after closing.
Multiple shielding top electrodes 1 are on a virtual annulus coaxial with the stator of the micro motor, corresponding every
The one shielding top electrode 1 is provided with the shielding hearth electrode 3, and shielding top electrode 1 and shielding hearth electrode 3 correspond shape
At internal shield.
The underface of each shielding hearth electrode 3 is provided with the measurement top electrode 5, and shielding bottom electricity
It insulate between pole 3 and the measurement top electrode 5.
Corresponding each measurement top electrode 5 is provided with the measurement hearth electrode 16, the measurement top electrode 5 and institute
It states measurement hearth electrode 16 and forms multiple capacitance structures, the rotor of the micro motor is able to drive each measurement hearth electrode when rotating
16 movements.When it is implemented, the measurement hearth electrode 16 may be provided on the rotor base plate 15 of the micro motor.
In order to support measuring device, the area of each shielding top electrode 1 is corresponded in the lower surface of the metal upper bed-plate 8
Domain is provided with bottom silicon 7, and the shielding top electrode 1 is fixed on the lower surface of the bottom silicon 7.
In order to realize internal shield and measure the insulation between top electrode 5, pushed up in the shielding hearth electrode 3 with the measurement
It is provided with the first insulating layer 4 between electrode 5, in the present embodiment, the first insulating layer 4 is SiN insulating layer.
In order to carry out insulation protection to measurement hearth electrode 16, the lower surface of the measurement hearth electrode 16 is additionally provided with second absolutely
Edge layer 6, in the present embodiment, second insulating layer 6 is also SiN insulating layer.
Further, since microactrator technique is mainly etching technics, original substrate is that grown one layer of zirconium
Silicon wafer (SOI, Silicon-On-Insulator) in the insulating substrate of lead titanate piezoelectric ceramics (PZT) film, thus it is existing
Sensor structure need during the preparation process PZT layers of etching completely are clean, and in the capacitance sensing tank etched into
The growth depositing operation of line sensor, so that technology difficulty increased dramatically, and the yield rate of flow is very low.It is asked for above-mentioned
Topic, the present invention are provided with lead titanate piezoelectric ceramics layer 2 between the shielding hearth electrode 3 and the shielding top electrode 1, realize
Process compatible with micro motor, effectively reduces technology difficulty.
Further, in this embodiment the measurement top electrode 5 be metal electrode, the measurement top electrode 5 is preferably
Gold electrode.
The present invention also provides a kind of micro motor, the micro motor includes above-mentioned embedded angle measurement unit.
The overall structure of the micro motor mainly includes five parts: stator structure, rotor structure, embedded detection sensor
Structure, testing capacitance array structure and outer shielding structure.Wherein, top electrode 1, lead titanate piezoelectric ceramics layer 2, shielding bottom are shielded
Electrode 3, the first insulating layer 4, measurement top electrode 5, second insulating layer 6 and bottom silicon 7 constitute embedded capacitance detecting angle measurement
The sensor structure of device.Stator bottom silicon 9,12 structure of stator PZT bottom electrode 10, stator PZT layer 11 and stator PZT top electrodes
At constituting the stator structure of micro motor.Frictional layer 13, rotor structure 14 and rotor base plate 15 constitute the rotor of micro motor
Structure.Multiple measurement hearth electrodes 16 are capacitor array structure to be detected, and metal upper bed-plate 8 is formed after being grounded with metal lower bottom base 17
Outer shielding structure.
In the actual work, the rotation of stator structure driving rotor structure, rotor structure drive testing capacitance array structure
It rotates with it, and periodically changes the testing capacitance between testing capacitance array and sensor structure, to pass through detection
The variation of capacitance is obtained with the variation of angle.
Fig. 2 gives the equivalent parameters model of measuring device.Wherein, external drive pumping signal is applied in inner shield,
And external shielding layer is directly grounded, for shielding the interference of external environment and micro motor driving signal.In Fig. 2, C1 is inner shield
With the parasitic capacitance between measurement top electrode 5, size is mainly by the area of measurement top electrode 5 and the thickness shadow of SiN insulating layer
It rings.Parasitic capacitance of the C2 between rotor structure and external shielding layer, size is mainly by the gap between rotor and external shielding layer
It influences.Hand capacity of the R1 between rotor structure and external shielding layer, size mainly by rotor during rotation with composition
The influence of contact condition between the metab of external shielding layer.Parasitic capacitance of the C3 between internal shield and external shielding layer,
Its size mainly by the thickness and internal shield of bottom silicon 7 and drivingly between gap influenced.
Measuring principle is as follows:
For plane-parallel capacitor, capacitance is
Wherein, S is the masked area of pole plate, unit m2;The dielectric coefficient of ε medium between pole plate;D is two parallel plate electrodes
Between distance, unit m;ε0For the dielectric constant in vacuum, size is 8.854 × 10-12F/m;εrThe phase of medium between pole plate
To dielectric constant, for air εr≈1.When measured parameter changes so that S, d or ε in formula change, capacitance C
Change therewith.If keeping two of them parameter constant, and only change one of parameter, so that it may which the variation of the parameter is converted
For the variation of capacitance, electricity output just can be exchanged by measuring circuit.The present invention is mainly to pass through the covering for changing pole plate
Area changes the size of capacitance.For each electrode, capacitance is
Wherein C1 ' expression measurement top electrode and measure hearth electrode overlapping region capacitance, C2 ' expression measure top electrode and
Measure the capacitance of hearth electrode Non-overlapping Domain.ε1The dielectric coefficient of medium, ε between expression overlapping region pole plate2Indicate non-overlap area
The dielectric coefficient of medium, S between the pole plate of domain1Indicate the masked area of overlapping region pole plate, S1Indicate the covering of Non-overlapping Domain pole plate
Area, d1Indicate the distance between two parallel plate electrode of overlapping region, d2Indicate the distance between two parallel plate electrode of Non-overlapping Domain.Rotor
In the course of rotation, the variation of generating period, completion are by the region of upper/lower electrode overlapping to the real-time monitoring of capacitance
The achievable real-time monitoring to rotor rotational angle.
It is as shown in Figure 3 for realizing the schematic block circuit diagram of capacitance detecting.As shown in figure 3, capacitive detection circuit mainly by
Analog front circuit and isolation amplification output circuit composition.Two groups of micro-structure capacitors are through double coaxial cables and shield guard connection
To analog front circuit.Analog front circuit is made of filter amplification circuit and isolating amplifier circuit;Output circuit is by signal
Demodulator circuit, high-precision AD Acquisition Circuit, arithmetic processing circuit and data output circuit composition, the real-time angle of final output
Signal is transferred to host computer by RS485 or SPI protocol.
Present invention employs after double shield structure design, embedded angle measurement unit not only can effectively shield extraneous
Electromagnetic environment interference, and it is possible to prevente effectively from interfered caused by micro motor driving signal.Meanwhile the embedded angle measurement dress
The preparation process set can be compatible with the preparation process of micro motor, therefore can be effectively reduced whole preparation process difficulty, just
It is completed the process in integration, improves the yield rate of flow preparation.
Each embodiment in this specification is described in a progressive manner, the highlights of each of the examples are with other
The difference of embodiment, the same or similar parts in each embodiment may refer to each other.
Used herein a specific example illustrates the principle and implementation of the invention, and above embodiments are said
It is bright to be merely used to help understand method and its core concept of the invention;At the same time, for those skilled in the art, foundation
Thought of the invention, there will be changes in the specific implementation manner and application range.In conclusion the content of the present specification is not
It is interpreted as limitation of the present invention.
Claims (9)
1. a kind of embedded angle measurement unit for micro motor, which is characterized in that the measuring device includes: bottom on metal
Seat, metal lower bottom base, multiple measurement top electrodes, multiple measurement hearth electrodes, multiple shielding top electrodes and multiple shielding hearth electrodes;Its
In,
The metal upper bed-plate lid, which is closed, forms closed cavity in the opening portion of the metal lower bottom base, and micro motor is located at the cavity
It is interior;
Multiple shielding top electrodes are on a virtual annulus coaxial with the stator of the micro motor, corresponding each described
Shielding top electrode is provided with the shielding hearth electrode;
The measurement top electrode, and the shielding hearth electrode and institute are provided with immediately below each shielding hearth electrode
It states and insulate between measurement top electrode;
Corresponding each measurement top electrode is provided with the measurement hearth electrode, the measurement top electrode and the measurement bottom
Electrode forms multiple capacitance structures, and the rotor of the micro motor is able to drive each measurement hearth electrode movement when rotating.
2. measuring device according to claim 1, which is characterized in that the lower surface of the metal upper bed-plate corresponds to each institute
The region for stating shielding top electrode is provided with bottom silicon, and the shielding top electrode is fixed on the lower surface of the bottom silicon.
3. measuring device according to claim 1, which is characterized in that the shielding hearth electrode and the measurement top electrode it
Between be provided with the first insulating layer.
4. measuring device according to claim 1, which is characterized in that the lower surface of the measurement top electrode is provided with second
Insulating layer.
5. measuring device according to claim 1, which is characterized in that the shielding hearth electrode and the shielding top electrode it
Between be provided with lead titanate piezoelectric ceramics layer.
6. measuring device according to claim 1, which is characterized in that the measurement top electrode is metal electrode.
7. measuring device according to claim 6, which is characterized in that the measurement top electrode is gold electrode.
8. measuring device according to claim 1, which is characterized in that the micro motor is arranged in the measurement hearth electrode
On rotor base plate.
9. a kind of micro motor, which is characterized in that the micro motor includes that the described in any item embedded angles of claim 1-8 are surveyed
Measure device.
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CN205175338U (en) * | 2015-12-04 | 2016-04-20 | 威海华菱光电股份有限公司 | Thickness check sensor |
CN107633993A (en) * | 2017-08-17 | 2018-01-26 | 南京市蔬菜科学研究所 | A kind of cold plasma double glow discharge vegetables and fruits device for treatment of seeds |
CN108253882A (en) * | 2018-04-10 | 2018-07-06 | 中国工程物理研究院电子工程研究所 | A kind of angle measurement unit of micro motor |
WO2019074588A1 (en) * | 2017-10-13 | 2019-04-18 | Nike Innovate C.V. | Footwear midsole with electrorheological fluid housing |
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2019
- 2019-05-27 CN CN201910444857.5A patent/CN110044253A/en active Pending
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
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CN1502157A (en) * | 2000-04-28 | 2004-06-02 | X2Y˥��������˾ | Predetermined symmetrically balanced amalgam with complementary paired portions comprising shielding electrodes and shielded electrodes and other predetermined element portions for symmetrically balan |
CN1425896A (en) * | 2003-01-28 | 2003-06-25 | 天津大学 | Non-contact composite capacitance electrode type displacement transducer and measurer |
CN200941093Y (en) * | 2005-11-18 | 2007-08-29 | 清华大学 | Probe-type capacity sensor for thickness measurement |
CN102753931A (en) * | 2009-12-31 | 2012-10-24 | 迈普尔平版印刷Ip有限公司 | Capacitive sensing system |
CN205175338U (en) * | 2015-12-04 | 2016-04-20 | 威海华菱光电股份有限公司 | Thickness check sensor |
CN107633993A (en) * | 2017-08-17 | 2018-01-26 | 南京市蔬菜科学研究所 | A kind of cold plasma double glow discharge vegetables and fruits device for treatment of seeds |
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