CN204388777U - PCB plane difference dynamic inductance formula angular displacement sensor - Google Patents

Abstract

This case is PCB plane difference dynamic inductance formula angular displacement sensor, its structure comprises: sensor stator and rotor sensor, wherein, sensor stator is a pcb board, pcb board is processed with two phase windings and the connector realizing conduction and connect of Copper Foil helical structure, every phase winding is made up of two windings in series diametrically, two phase windings comprise four windings altogether, each winding in these four windings is according to the different stacked equivalent layer number of the PCB number of plies, the Copper Foil hand of spiral of each layer laminate is identical, and winding is connected with outside with connector by the wire on PCB; Rotor sensor is made up of two identical ferromagnetic material thin slices and rotation axis, each ferromagnetic material thin slice is the fan loop configuration of radial symmetry, two ferromagnetic thin slices are installed on an axle, axially symmetrical each other, and on thin slice and stator pcb board, axis of winding does not come in contact; Described axle is concentric with winding, and the magnetic flux that winding is produced by electric current is by two panels ferromagnetic material thin slice, and the air gap between thin slice and winding forms closed magnetic circuit.The sensor construction of this case is simple, easy for installation.

Description

PCB plane difference dynamic inductance formula angular displacement sensor

Technical field

The utility model relates to a kind of difference induction formula angular displacement sensor, particularly relates to a kind of PCB plane difference dynamic inductance formula angular displacement sensor.

Background technology

Angular measure is the important component part of measuring science, is widely used in the fields such as machinery, optics, Aeronautics and Astronautics, navigation.

Relative to low life-span, the difficult contact type angle sensor safeguarded, contactless angular transducer can avoid friction, and then avoid affecting the unreliability on measuring accuracy and critical component, main non-contact angle sensor, according to its principle of work, is divided into optical principle and electromagnetic induction principle non-contact angle sensor.Adopt the sensor accuracy class of optical principle high, but due to the restriction of attribute own, manufacture assembling difficulty, also have certain requirement to environment for use.And easy to manufacture based on the sensor of electromagnetic induction principle, can use in comparatively rugged environment.

Difference induction formula angular displacement sensor is the one of electromagnetic induction principle sensor.Conventional difference induction formula angular displacement sensor comparatively optical sensor is simple, but also relative to there is part number of packages many, the problem that assembly process is many.

Utility model content

For overcoming the deficiencies in the prior art, the purpose of this utility model is to provide a kind of plane changed area difference induction formula angular displacement sensor, the structure being intended to use Copper Foil spiral stacked is as winding, substitute general core inductor, realize high precision, high sensitivity, measurement of angle that antijamming capability is strong with simple structure.

For achieving the above object, the utility model is achieved through the following technical solutions:

PCB plane difference dynamic inductance formula angular displacement sensor, its structure comprises: sensor stator and rotor sensor,

Wherein, sensor stator is a pcb board, pcb board is processed with two phase windings and the connector realizing conduction and connect of Copper Foil helical structure, every phase winding is made up of two windings in series diametrically, two phase windings comprise four windings altogether, each winding in these four windings is according to the different stacked equivalent layer number of the PCB number of plies, and each layer laminate Copper Foil hand of spiral is identical, and winding is connected with outside with connector by the wire on PCB;

Rotor sensor is made up of two identical ferromagnetic material thin slices and rotation axis, each ferromagnetic material thin slice is the fan loop configuration of radial symmetry, two ferromagnetic thin slices are installed on an axle, axially symmetrical each other, and on thin slice and stator pcb board, axis of winding does not come in contact; Described axle is concentric with winding, and the magnetic flux that winding is produced by electric current is by two panels ferromagnetic material thin slice, and the air gap between thin slice and winding forms closed magnetic circuit.

Preferably, described PCB plane difference dynamic inductance formula angular displacement sensor, wherein, described four windings are concentric screw fan loop configuration.

Preferably, described PCB plane difference dynamic inductance formula angular displacement sensor, wherein, rotor ferromagnetic thin slice fan ring outside diameter is greater than stator winding coil fan ring outside diameter, and in rotor ferromagnetic thin slice fan ring, circular diameter is less than circular diameter in stator winding coil fan ring;

Preferably, described PCB plane difference dynamic inductance formula angular displacement sensor, wherein, described stator fan ring central angle is greater than the half of rotor fan ring central angle.

Preferably, described PCB plane difference dynamic inductance formula angular displacement sensor, wherein, the number of plies of described PCB is individual layer, bilayer or is greater than two-layer.

Preferably, described PCB plane difference dynamic inductance formula angular displacement sensor, wherein, between the ferromagnetic thin slice of rotor and stator PCB, air gap thickness is greater than 0 and is less than or equal to 1mm.

Preferably, described PCB plane difference dynamic inductance formula angular displacement sensor, wherein, when two windings in series in every phase winding connect, its connected mode will guarantee that its magnetic flux superposes mutually in magnetic circuit.

The beneficial effects of the utility model: 1) this sensor does not exist the element to factor sensitivities such as temperature, humidity, dusts, environment for use restriction is less, can in environmental applications such as high temperature, high humidity, many dirt; 2) this sensor is that inductance exports, and follow-up testing circuit is simple, and antijamming capability is strong; 3) compared with general core inductor, by the stacked structure of Copper Foil spiral as winding, structure is simple, processing technology is simple, easy for installation, achieve high precision, high sensitivity, measurement of angle that antijamming capability is strong, cost, size, reliability aspect are all improved.

Accompanying drawing explanation

Fig. 1 is the structural drawing in the PCB plane difference dynamic inductance formula angular displacement sensor described in the utility model one embodiment;

Fig. 2 is the rotor sensor structural drawing in the PCB plane difference dynamic inductance formula angular displacement sensor described in the utility model one embodiment;

The winding construction figure of PCB top layer on sensor stator during Fig. 3 PCB two-sided for the employing in the PCB plane difference dynamic inductance formula angular displacement sensor described in the utility model one embodiment;

The winding construction figure of PCB bottom on sensor stator during Fig. 4 PCB two-sided for the employing in the PCB plane difference dynamic inductance formula angular displacement sensor described in the utility model one embodiment;

The rotor turns angle that Fig. 5 is the actual measurement in the PCB plane difference dynamic inductance formula angular displacement sensor described in the utility model one embodiment and winding inductance differential values graph of a relation.

Embodiment

Below in conjunction with accompanying drawing, the utility model is described in further detail, can implements according to this with reference to instructions word to make those skilled in the art.

Because ferromagnetic material thin slice and axis of winding are apart from very little, and when not considering magnetic circuit iron loss, the total magnetic resistance of engineering approximation magnetic circuit is

$R_m=\frac{2l}{{\mathrm{\μA}}_f}+\frac{4\mathrm{\δ}}{{\mathrm{\μ}}_{0}A}$

L in formula---ferromagnetic material thin slice magnetic conduction length;

μ---ferromagnetic material magnetic permeability;

A _f---ferromagnetic material thin slice equivalence magnetic conduction cross-sectional area;

δ---gas length;

μ ₀---air permeability;

A---air gap magnetic conduction cross-sectional area.

The magnetic permeability that the magnetic permeability of ferromagnetic material compares air is very large, therefore the magnetic resistance of ferromagnetic material can be ignored when calculating, therefore

$R_m=\frac{4\mathrm{\δ}}{{\mathrm{\μ}}_{0}A}$

The self-induction L of winding and the inversely proportional relation of magnetic resistance, therefore

$L=\frac{W^2}{R_m}=\frac{W^2{\mathrm{\μ}}_{0}A}{4\mathrm{\δ}}$

W in formula---coil turn.

When rotor sensor rotates, the gas length between sensor stator, rotor is constant, and air gap area changes with rotational angle.Air gap area variable quantity and the proportional relation of rotational angle.Corresponding to two air gaps of two phase windings, variable quantity is identical, but during an increase, another reduces, and is differential relationship, therefore two phase winding air gap area A ₁, A ₂be respectively

$\left\{\begin{array}{c}{A}_1=A_{10}+\mathrm{K\θ}\\ A_2=A_{20}-\mathrm{K\θ}\end{array}\right.$

A in formula ₁₀, A ₂₀the initial air gap area of two phase windings;

K---proportionality constant;

θ---rotor turns angle.

So, the self-induction L of two phase windings ₁, L ₂for

$\left\{\begin{array}{c}{L}_1=\frac{W^2{\mathrm{\μ}}_0{A}_{10}}{4\mathrm{\δ}}+\frac{W^2{\mathrm{\μ}}_0\mathrm{K\θ}}{4\mathrm{\δ}}\\ L_2=\frac{W^2{\mathrm{\μ}}_0{A}_{20}}{4\mathrm{\δ}}+\frac{W^2{\mathrm{\μ}}_0\mathrm{K\θ}}{4\mathrm{\δ}}\end{array}\right.$

So the two phase winding self-inductions that the rotation due to rotor causes are changed to differential relationship, L ₁, L ₂difference DELTA L is

$\mathrm{\ΔL}=L_1-L_2=\frac{W^2{\mathrm{\μ}}_0(A_{10}-A_{20})}{4\mathrm{\δ}}+\frac{W^2{\mathrm{\μ}}_0\mathrm{K\θ}}{2\mathrm{\δ}}$

Make constant term $\frac{W^2{\mathrm{\μ}}_0(A_{10}-A_{20})}{4\mathrm{\δ}}=\mathrm{\Δ}{L}_0,$ Therefore

$\mathrm{\ΔL}={\mathrm{\ΔL}}_0+\frac{W^2{\mathrm{\μ}}_0\mathrm{K\θ}}{2\mathrm{\δ}}$

Namely the difference in inductance momentum of two-phase difference induction and rotor turns angle linear, by measuring the difference of two phase winding self-inductions, rotor turns angle can be obtained.

For ensureing that sensor has maximum linearity range, during installation, initial position of rotor should be symmetrical with rotor windings.Now, the rotor turns angular range can measured and linear sensor scope are

$\mathrm{\θ}\∈(-\frac{\mathrm{\α}}{2},\frac{\mathrm{\α}}{2})\∩(-\frac{2\mathrm{\β}-\mathrm{\α}}{2},\frac{2\mathrm{\β}-\mathrm{\α}}{2})$

Wherein α---rotor fan annular ferromagnetic thin slice central angle

Transducer sensitivity S is

$S=\frac{W^2{\mathrm{\μ}}_{0}K}{2\mathrm{\δ}}$

Change W, δ and can change transducer sensitivity.A feasible method is, sensor stator pcb board adopts multilayer circuit board, when every layer of umber of turn is certain, increases the number of plies that winding is stacked, can improve the number of turn of winding, improve sensitivity; Or reduce air gap thickness and improve sensitivity.

The following drawings be all with two-sided PCB for example, PCB plane difference dynamic inductance formula angular displacement sensor, its structure comprises: sensor stator and rotor sensor, refers to accompanying drawing 1,

Wherein, sensor stator is a pcb board, pcb board is processed with two phase windings and the connector realizing conduction and connect of Copper Foil helical structure, every phase winding is made up of two windings in series diametrically, two phase windings comprise four windings altogether, each winding in these four windings is according to the different stacked equivalent layer number of the PCB number of plies, and each layer laminate Copper Foil hand of spiral is identical, and winding is connected with outside with connector by the wire on PCB;

Refer to accompanying drawing 2, rotor sensor is made up of two identical ferromagnetic material thin slices and rotation axis, and each ferromagnetic material thin slice is the fan loop configuration of radial symmetry, and two ferromagnetic thin slices are installed on an axle, axially symmetrical each other, on thin slice and stator pcb board, axis of winding does not come in contact; Described axle is concentric with winding, and the magnetic flux that winding is produced by electric current is by two panels ferromagnetic material thin slice, and the air gap between thin slice and winding forms closed magnetic circuit.

The utility model can also comprise following situation, and described four windings are concentric screw fan loop configuration.

Further, rotor ferromagnetic thin slice fan ring outside diameter is greater than stator winding coil fan ring outside diameter, and in rotor ferromagnetic thin slice fan ring, circular diameter is less than circular diameter in stator winding coil fan ring;

Further, described stator fan ring central angle is greater than the half of rotor fan ring central angle.

The utility model also comprises following distortion, and the number of plies of described PCB is individual layer, bilayer or is greater than two-layer.

Preferably, between the ferromagnetic thin slice of rotor and stator PCB, air gap thickness is greater than 0 and is less than or equal to 1mm.

Preferably, when two windings in series in every phase winding connect, its connected mode will guarantee that its magnetic flux superposes mutually in magnetic circuit.

Below in conjunction with reality, a specific embodiment of the present utility model is described in detail.

Sensor stator PCB material FR-4 base material, 1.6mm thickness of slab, dual platen.Stator PCB is the circle of diameter 33mm, and there is the hole passed for the axle of rotor of a diameter 8mm at center, has the mounting hole of two diameter 3.3mm near PCB marginal portion.Winding coil is stacked two-layer, and process respectively at the top layer of PCB and bottom, two interlayers are connected by via hole.Winding is the fan loop configuration of two groups of radial symmetry, and fan ring outside diameter 28mm, interior circular diameter 13mm, 50 °, central angle, coil live width 0.127mm, every layer of 7 circle coil, the hand of spiral of coil, stacked situation, connected mode refer to accompanying drawing 3 and accompanying drawing 4.

Rotor sensor adopts electromagnetic pure iron, thickness 1mm, and fan ring outside diameter 31mm, interior circular diameter 10mm, 30 °, central angle, there is the hole of a 6mm diameter centre for being installed on rotation axis.

Sensor integral installation accompanying drawings 1, rotor center rotation axis is installed with stator center hole is concentric, air gap thickness 1mm between the ferromagnetic thin slice of rotor and stator PCB.

Accompanying drawing 5 is measurement result figure, and in the scope of (-15 °, 15 °), two-phase winding inductance difference and rotational angle are linear relationship.

Although embodiment of the present utility model is open as above, but it is not restricted to listed in instructions and embodiment utilization, it can be applied to various applicable field of the present utility model completely, for those skilled in the art, can easily realize other amendment, therefore do not deviating under the universal that claim and equivalency range limit, the utility model is not limited to specific details and illustrates here and the legend described.

Claims (7)

1.PCB plane difference dynamic inductance formula angular displacement sensor, it is characterized in that, its structure comprises: sensor stator and rotor sensor,

Wherein, sensor stator is a pcb board, pcb board is processed with two phase windings and the connector realizing conduction and connect of Copper Foil helical structure, every phase winding is made up of two windings in series diametrically, two phase windings comprise four windings altogether, each winding in these four windings is according to the different stacked equivalent layer number of the PCB number of plies, and each layer laminate Copper Foil hand of spiral is identical, and winding is connected with outside with connector by the wire on PCB;

Rotor sensor is made up of two identical ferromagnetic material thin slices and rotation axis, each ferromagnetic material thin slice is the fan loop configuration of radial symmetry, two ferromagnetic thin slices are installed on an axle, axially symmetrical each other, and on thin slice and stator pcb board, axis of winding does not come in contact; Described axle is concentric with winding, and the magnetic flux that winding is produced by electric current is by two panels ferromagnetic material thin slice, and the air gap between thin slice and winding forms closed magnetic circuit.

2. PCB plane difference dynamic inductance formula angular displacement sensor as claimed in claim 1, it is characterized in that, described four windings are concentric screw fan loop configuration.

3. PCB plane difference dynamic inductance formula angular displacement sensor as claimed in claim 2, it is characterized in that, rotor ferromagnetic thin slice fan ring outside diameter is greater than stator winding coil fan ring outside diameter, and in rotor ferromagnetic thin slice fan ring, circular diameter is less than circular diameter in stator winding coil fan ring.

4. PCB plane difference dynamic inductance formula angular displacement sensor as claimed in claim 3, is characterized in that, described stator fan ring central angle is greater than the half of rotor fan ring central angle.

5. PCB plane difference dynamic inductance formula angular displacement sensor as claimed in claim 4, it is characterized in that, the number of plies of described PCB is individual layer, bilayer or is greater than two-layer.

6. PCB plane difference dynamic inductance formula angular displacement sensor as claimed in claim 5, it is characterized in that, between the ferromagnetic thin slice of rotor and stator PCB, air gap thickness is greater than 0 and is less than or equal to 1mm.

7. PCB plane difference dynamic inductance formula angular displacement sensor as claimed in claim 6, is characterized in that, when two windings in series in every phase winding connect, its connected mode will guarantee that its magnetic flux superposes mutually in magnetic circuit.