CN206891377U - A kind of angular displacement sensor - Google Patents
A kind of angular displacement sensor Download PDFInfo
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- CN206891377U CN206891377U CN201720223961.8U CN201720223961U CN206891377U CN 206891377 U CN206891377 U CN 206891377U CN 201720223961 U CN201720223961 U CN 201720223961U CN 206891377 U CN206891377 U CN 206891377U
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Abstract
Sensor technical field is the utility model is related to, especially a kind of angular displacement sensor, including rotor magnetic steel ring, stator assembly and shielding construction.Angular displacement sensor of the present utility model is provided with the shielding construction of shielding external magnetic field, it can prevent external magnetic field from disturbing, improve initial signal quality, ensure precision, in addition, using integrated magnetic induction part, initial signal uniformity and phase accuracy are improved, miniaturized design is suitable for, and is also suitable for large-diameter design.
Description
Technical field
It the utility model is related to angular position pick up technical field, more particularly to a kind of angular displacement sensor.
Background technology
The position detecting device applied in Motor Control Field is mainly encoder, and encoder one kind is by rotor
The physical quantitys such as spin angular position, angular speed are converted to the position sensor of pulse or numeral, and the resolution ratio and precision of encoder are straight
Connect and have influence on automated system control performance.
At present, the encoder applied in field of engineering technology is mainly optical-electricity encoder, however, photoelectric encoder is present
The shortcomings that some are difficult to overcome：Photoelectric encoder is formed by glass substance by groove, and its anti-vibration and impact capacity be not strong, and
And it is not suitable for the adverse circumstances such as dust, condensation, structure and positioning assembling are complicated；Ruling span has the limit, to improve resolution ratio
Code-disc must be increased, so as to be difficult to miniaturization；Assembly precision requires very high in production process, directly influences production effect
Rate, finally influence product cost.
Magneto-electric encoder can solve the deficiency of photoelectric encoder.Chinese patent ZL2009101 37761.0 is proposed
A kind of magnetism encoder, including magnet steel ring, magnetic guiding loop and magnetic induction part, wherein, magnetic guiding loop is by two sections or the same radius of multistage, same
The segmental arc in the center of circle is formed, and adjacent two segmental arc leaves gap, and magnetic induction part is placed in the gap, when magnet steel ring and magnetic guiding loop occur
During relative rotary motion, the magnetic signal sensed is converted to voltage signal by magnetic induction part, and the voltage signal is transferred to
Corresponding signal processing apparatus.
A kind of magneto-electric rotation angle detecting method is disclosed in Japan Patent TOHKEMY 2004-340681A, discloses one
In the case that kind is without using temperature sensor, temperature drift amount is calculated using two phase signals quadratic sums, so as to reduce temperature drift
Move and the method influenceed is detected on angle.
In summary, existing magneto-electric Angle Position detection method has following defect：1. a pair external magnetic field does not have shielding measure,
Reliability is not high；2. pair demand on signal quality is higher, if signal higher harmonic components are higher, two phase signals quadratic sums are not normal
Number, then influence effectively to eliminate caused by temperature drift；3. it is applicable just for two phase signals；4. between have ignored each phase signals
Temperature drift amount difference, accuracy of detection can be influenceed in practical application.
Utility model content
The purpose of this utility model is not high, poor reliability scarce in order to solve accuracy of detection present in prior art
Point, and a kind of angular displacement sensor proposed.
To achieve these goals, the utility model employs following technical scheme：
The utility model angular displacement sensor includes rotor magnetic steel ring and stator assembly, and the stator assembly includes outer
The body and shielding steel loop being built in outer sleeve body, Hall magnetic induction part and PCB, the outer sleeve body have inner ring
Boss, the rotor magnetic steel ring are located in the annular mouth of the inner ring boss and freely rotated, the outer circumference of the inner ring boss
On uniformly lay multiple Hall magnetic induction parts, the shielding is arranged in the periphery of multiple Hall magnetic induction parts upwards
Steel loop, the PCB are set on the inner ring boss and electrically connected with the Hall magnetic induction part.
Outer sleeve body described in the utility model is fixed on motor rear flange face, and the rotor magnetic steel ring set is mounted in motor tailing axle
On, the rotor magnetic steel ring freely rotates relative to the outer sleeve body, and the Hall magnetic induction part is used for inductiopn rotor magnet steel
Magnetic signal is simultaneously converted into analog voltage signal output by magnetic field caused by ring, multiple Hall magnetic induction parts output A+, A-,
The road signal of B+, B- tetra-, wherein relative two Hall magnetic induction parts output is A+ and A- or B+ and B- signals, it is described
PCB is used to handle the analog voltage signal of Hall magnetic induction part output and exports A, B by signaling interface
Two-phase simulation voltage signal.
The periphery of inner ring boss described in the utility model is provided with annular groove upwards, and the shielding steel is set in the annular groove
Ring, is provided with multiple square grooves being circular layout between the annular groove and the inner ring boss, set in the square groove described in
Hall magnetic induction part, the periphery of the annular groove is outer shroud boss, and the inner ring boss forms inner trough structure with outer shroud boss
For embedding encapsulating body.
Alignment pin and screw are additionally provided with outer sleeve body described in the utility model, the alignment pin is used for location and installation PCB electricity
Road plate, the screw and tapping screw, which cooperate, locks the PCB, and the outer sleeve body is towards the motor rear flange
The one side in face has an annular boss, and the outer sleeve body is by annular boss and motor rear flange face pre-determined bit, on the outer sleeve body
Slotted eye is additionally provided with, the slotted eye is cooperated with lock-screw so that the outer sleeve body is locked on the motor rear flange face.
The utility model proposes Angle Position detection method and the beneficial effect of angular displacement sensor be：
1st, angular displacement sensor is provided with the shielding construction of shielding external magnetic field, can prevent external magnetic field from disturbing, and improves just
Beginning signal quality, ensure precision；
2nd, using integrated magnetic induction part, initial signal uniformity and phase accuracy are improved；
3rd, miniaturized design is suitable for, and is also suitable for large-diameter design.
Brief description of the drawings
Below in conjunction with the accompanying drawing in the utility model embodiment, the technical scheme in the embodiment of the utility model is carried out
Clearly and completely describe.
Fig. 1 is the angular displacement sensor structure schematic diagram in the present embodiment one；
Fig. 2 is the configuration schematic diagram of the angular displacement sensor in the present embodiment one；
Fig. 3 is the outer sleeve body front view of the angular displacement sensor in the present embodiment one；
Fig. 4 is the outer sleeve body rearview of the angular displacement sensor in the present embodiment one；
Fig. 5 is the cross section structure diagram of the angular displacement sensor in the present embodiment one；
Fig. 6 is the angle calculation theory diagram of the angular displacement sensor of the present embodiment.
In figure：It is 1 rotor magnetic steel ring, 2 stator assemblies, 21 outer sleeve bodies, 211 annular grooves, 212 inner ring boss, 213 square
Groove, 214 alignment pins, 215 outer shroud boss, 216 screws, 217 annular boss, 218 slotted eyes, 22 shielding steel loops, 23 Hall magnetic induction
Element, 24PCB circuit boards, 25 tapping screws, 26 encapsulating bodies, 3 lock-screws.
Embodiment
In description of the present utility model, it is to be understood that term " radial direction ", " axial direction ", " on ", " under ", " top ",
The orientation or position relationship of the instruction such as " bottom ", " interior ", " outer " are based on orientation shown in the drawings or position relationship, merely to just
In description the utility model and simplified description, rather than indicate or imply that signified device or element must be with specifically square
Position, with specific azimuth configuration and operation, therefore it is not intended that to limitation of the present utility model.In description of the present utility model
In, unless otherwise indicated, " multiple " are meant that two or more.
, it is necessary to which explanation, unless otherwise clearly defined and limited, term " are pacified in description of the present utility model
Dress ", " setting ", " connection " should be interpreted broadly, for example, it may be being fixedly connected or being detachably connected, or integrally be connected
Connect；Can be joined directly together, can also be indirectly connected by intermediary.For the ordinary skill in the art, may be used
To understand concrete meaning of the above-mentioned term in the utility model as the case may be.
Embodiment one：
As Figure 1-5, the angular displacement sensor of the present embodiment includes rotor magnetic steel ring 1 and stator assembly 2, rotor magnetic
The geomery of steel loop 1 and stator assembly 2 can wrap according to the electric machine structure flexible design of installation to be coordinated, stator assembly 2
Shielding steel loop 22, Hall magnetic induction part 23 and the PCB 24 for including outer sleeve body 21 and being built in outer sleeve body 21, overcoat
Body 21 has inner ring boss 212, and rotor magnetic steel ring 1 is located in the annular mouth of inner ring boss 212 and freely rotated, inner ring boss
Multiple Hall magnetic induction parts 23 are uniformly laid in 212 periphery upwards, and the periphery of multiple Hall magnetic induction parts 23 is arranged upwards
Steel loop 22 is shielded, PCB circuit boards 24 are set on inner ring boss and electrically connected with Hall magnetic induction part 23, Hall magnetic induction
Element 23 is used for magnetic field caused by inductiopn rotor magnet steel ring 1 and magnetic signal is converted into analog voltage signal output, multiple Halls
Magnetic induction part 23 exports the road signal of A+, A-, B+, B- tetra-, wherein the output of relative two Hall magnetic induction parts 23 for A+ and
A- or B+ and B- signals, PCB 24 are used to handle the analog voltage signal that Hall magnetic induction part 23 exports
And A, B two-phase simulation voltage signal are exported by signaling interface, wherein, shielding steel loop 22 can shield external interference magnetic field, protect
Magnetic field caused by rotor magnetic steel ring 1 is protected, so that it is guaranteed that the simulation electricity that the Hall magnetic induction part 23 in PCB 24 is exported
Press signal quality.
The rotor magnetic steel ring 1, Hall magnetic induction part 23 and shielding steel loop 22 of the present embodiment are substantially at together from structure
On one vertical plane.
The outer sleeve body 21 of the present embodiment is fixed on motor rear flange face 9, and rotor magnetic steel ring 1 is sleeved on motor tailing axle 8
On, rotor magnetic steel ring 1 freely rotates relative to outer sleeve body 21, wherein, rotor magnetic steel ring 1 can be that single pair pole is magnetized, can also
It is multipair pole；Can be parallel magnetization or radial magnetizing.The angular displacement sensor small volume of the present embodiment, structure letter
Single compact, rotor magnetic steel ring 1 is sleeved on motor tailing axle 8, and with magnetic steel special glue, so as to rotation synchronous with rotor
Turn, stator assembly 2 can be fixed on motor rear flange face 9 by lock-screw 3, therefore easy installation and removal, not by motor
The length dimension of tailing axle 8 limits.
The periphery of the inner ring boss 212 of the present embodiment is provided with annular groove 211 upwards, and shielding steel loop is set in annular groove 211
22, multiple square grooves 213 being circular layout are provided between annular groove 211 and inner ring boss 212, Hall is set in square groove 213
Magnetic induction part 23, the periphery of annular groove 211 is outer shroud boss 215, and inner ring boss 212 forms inside groove knot with outer shroud boss 215
Structure is used for embedding encapsulating body 26, and encapsulating body 26 is used for the embedding of stator assembly 2, so as to improve reliability and service life.
Alignment pin 214 and screw 216 are additionally provided with the outer sleeve body 21 of the present embodiment, alignment pin 214 is used for location and installation
PCB 24, screw 216 and tapping screw 25 cooperate locking PCB 24, and outer sleeve body 21 is towards motor rear flange
The one side in face 9 has annular boss 217, and outer sleeve body 21 passes through annular boss 217 and the pre-determined bit of motor rear flange face 9, outer sleeve body
Slotted eye 218 is additionally provided with 21, slotted eye 218 cooperates so that outer sleeve body 21 is locked into motor rear flange face 9 with lock-screw 3
On.
There is gap between the rotor magnetic steel ring 1 and stator assembly 2 of the present embodiment, in contactless state, therefore in electricity
Rotation or temperature change are big at a high speed for machine, have the abrasion that there will not be under the adverse circumstances such as dust greasy dirt mechanically, can so as to improve
By property and service life.
Fig. 6 shows angle during diagonal displacement sensor signal generation part output two phase signals of A, B in the present embodiment
Computing Principle block diagram, the Angle Position detection method comprise the following steps：
S01. sampling processing：Primary signal A, B progress sampling processing caused by diagonal displacement sensor obtains two and believed
Number real-time sampling value U'A、U'B；
S02. correcting process：The two phase signals real-time sampling value U' obtained to sampling processingA、U'BProcessing is modified to obtain
Two-phase is used for the signal value U " for inquiring about calibration dataA、U”B；
S03. interval judgement：Two-phase signal value U " after correcting processA、U”BInterval judgement is carried out again obtains section letter
Breath；
S04. angle is obtained：With block information and revised two-phase signal value U "A、U”BAs input, by with school
The mutual transmission of quasi- data carries out angle calculation, obtains angle value θA、θB；
S05. output is adjusted：To angle value θA、θBCarry out adjusting final output angle value θ again；
S06. correction calculates：After the completion of step S04, according to angle value θA、θBΔ θ is obtained by mathematic interpolation, then is tied
Close block information, revised two-phase signal value U "A、U”B, carry out to zero point offset amount U_offset, ratio correction value K0, ratio
Correction value K1It is respective it is independent calculate, draw U_offset、K0、K1；
S07. correcting process is circulated：U as obtained by calculating correction_offset、K0、K1To two phase signals real-time sampling values
U'A、U'BProcessing is modified, and step S01-S06 is repeated in some cycles.
Correction calculates and uses recursive algorithm in above-mentioned Angle Position detection method, specific as follows：
S501：Calibration data relational expression is：
Meaning of parameters is：
AWidth--- A phase signals amplitudes； BWidth--- B phase signals amplitudes；
UA--- A phase signals values； UB--- B phase signals values；
θ --- signal corresponding angles angle value.
Real-time sampling value relational expression is：
Meaning of parameters is：
A'Width--- A phase signals amplitude real-time sampling values；
B'Width--- B phase signals amplitude real-time sampling values；
UA_offset--- A phase signals zero point offset amounts；
UB_offset--- B phase signals zero point offset amounts；
U'A--- A phase signals real-time sampling values；
U'B--- B phase signals real-time sampling values.
Wherein：Initialize amplitude proportion correction value：K0=K1=1；
Inquiry calibration data numerical formula be：
Meaning of parameters is：
U'A(k)--- kth cycle A phase signals real-time sampling value；
U'B(k)--- kth cycle B phase signals real-time sampling value；
K0(k-1)--- the period proportional correction value of kth -1；
U”A(k)--- for inquiring about the A phase signals values of calibration data；
U”B(k)--- for inquiring about the B phase signals values of calibration data.
Use U "A(K)、U”B(K)The angle value that inquiry calibration data obtains：θA(K)、θB(K)；
Obtain angle overall error：Δθ(K)=θB(K)-θA(K)；
θAError with angle true value θ is：
θBError with angle true value θ is：Meaning of parameters
For：
θA--- the angle value that A phase signals value inquiry calibration data obtains；
θB--- the angle value that B phase signals value inquiry calibration data obtains；
ΔθA(k)--- the error discreet value that kth cycle A phases are looked between angle and true value angle；
ΔθB(k)--- the error discreet value that kth cycle B phases are looked between angle and true value angle.
S502：Output angle angle value is judged according to interval division：θOutputFor θA(K)Or θB(K)；
And θA is true (K)=θA(K)+ΔθA(K)Or θB is true (K)=θB(K)+ΔθB(K)；
Meaning of parameters is：
θA is true (k)--- the real angle discreet value that the kth cycle is obtained by A phases；
θB is true (k)--- the real angle discreet value that the kth cycle is obtained by B phases.
Then amplitude error value：ΔUA is true (K)=Δ θA(K)·AcosθA is true (K)；ΔUB is true (K)=-Δ θB(K)·BsinθB is true (K)；Ginseng
Counting implication is：
ΔUA is true (k)--- the A phases amplitude error discreet value of kth cycle；
ΔUB is true (k)--- the B phases amplitude error discreet value of kth cycle.
S503：Ratio correction value formula is calculated according to interval division：
K0(K)=K0(K-1)+ΔUA is true (K)/(UA′(K)-UA_offset)；
Or K0(K)=K0(K-1)+ΔUB is true (K)/((UB′(K)-UB_offset)K1).Meaning of parameters is：
K0(k)--- kth period proportional correction value.
It is described above, the only preferable embodiment of the utility model, but the scope of protection of the utility model is not
This is confined to, any one skilled in the art is in the technical scope that the utility model discloses, according to this practicality
New technical scheme and its utility model design are subject to equivalent substitution or change, should all cover in protection model of the present utility model
Within enclosing.
Claims (4)
- A kind of 1. angular displacement sensor, it is characterised in that：Including rotor magnetic steel ring (1) and stator assembly (2), the stator pack Fit (2) include outer sleeve body (21) and the shielding steel loop (22), the Hall magnetic induction part (23) that are built in outer sleeve body (21) With PCB (24), the outer sleeve body (21) has inner ring boss (212), and the rotor magnetic steel ring (1) is located at the inner ring Rotate in the annular mouth of boss (212) and freely, multiple Halls are uniformly laid in the periphery of the inner ring boss (212) upwards Magnetic induction part (23), the shielding steel loop (22) is arranged in the periphery of multiple Hall magnetic induction parts (23) upwards, described PCB (24) is set on the inner ring boss and electrically connected with the Hall magnetic induction part (23).
- 2. a kind of angular displacement sensor according to claim 1, it is characterised in that the outer sleeve body (21) is fixed on motor On rear flange face (9), the rotor magnetic steel ring (1) is sleeved on motor tailing axle (8), and the rotor magnetic steel ring (1) is relative to institute State outer sleeve body (21) freely to rotate, the Hall magnetic induction part (23) is used for magnetic field caused by inductiopn rotor magnet steel ring (1) simultaneously Magnetic signal is converted into analog voltage signal output, multiple Hall magnetic induction part (23) output A+, A-, B+, B- tetra- tunnels Signal, wherein relative two Hall magnetic induction parts (23) output is A+ and A- or B+ and B- signals, the PCB (24) it is used to handle the analog voltage signal of Hall magnetic induction part (23) output and A, B two is exported by signaling interface Phase analog voltage signal.
- A kind of 3. angular displacement sensor according to claim 2, it is characterised in that the periphery of the inner ring boss (212) Annular groove (211) is provided with upwards, and the shielding steel loop (22), the annular groove (211) and institute are set in the annular groove (211) State and multiple square grooves (213) being circular layout be provided between inner ring boss (212), set in the square groove (213) described in suddenly That magnetic induction part (23), the periphery of the annular groove (211) is outer shroud boss (215), the inner ring boss (212) and outer shroud Boss (215) forms inner trough structure and is used for embedding encapsulating body (26).
- 4. a kind of angular displacement sensor according to claim 3, it is characterised in that it is fixed to be additionally provided with the outer sleeve body (21) Position pin (214) and screw (216), the alignment pin (214) are used for location and installation PCB (24), the screw (216) and Tapping screw (25), which cooperates, locks the PCB (24), and the outer sleeve body (21) is towards the motor rear flange face (9) one side has an annular boss (217), and the outer sleeve body (21) is pre- by annular boss (217) and motor rear flange face (9) Positioning, is additionally provided with slotted eye (218) on the outer sleeve body (21), and the slotted eye (218) and lock-screw (3) cooperate with by institute Outer sleeve body (21) is stated to be locked on the motor rear flange face (9).
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| Application Number | Priority Date | Filing Date | Title |
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| CN201721438703.8U CN207675115U (en) | 2017-03-09 | 2017-03-09 | A kind of angular displacement sensor |
| CN201720223961.8U CN206891377U (en) | 2017-03-09 | 2017-03-09 | A kind of angular displacement sensor |
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| CN201720223961.8U CN206891377U (en) | 2017-03-09 | 2017-03-09 | A kind of angular displacement sensor |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108880126A (en) * | 2018-08-21 | 2018-11-23 | 桂林智神信息技术有限公司 | A kind of motor and the hand-held stabilizer of lightweight of stabilizer |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110411403A (en) * | 2019-08-22 | 2019-11-05 | 深圳南方德尔汽车电子有限公司 | A kind of integrated form oil pump angular transducer and integrated electric pump control unit device |
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2017
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108880126A (en) * | 2018-08-21 | 2018-11-23 | 桂林智神信息技术有限公司 | A kind of motor and the hand-held stabilizer of lightweight of stabilizer |
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