CN1818539A - Method and sensor for measuring radial and axial displacement of synchronouslly rotation axis - Google Patents

Abstract

A method for measuring both axial and radial displacements of rotary shaft includes setting rotator and stator on rotary shaft to be measured to form displacement measuring transducer, making stator be circular iron core with tooth shaped probe on internal ring, winding coil of each probe in self-conduction way, calculating out axial displacement at X direction and radial displacement at X direction of rotary shaft according to parameters of air-gap magnetic conductivity and total number of turns on coil as well as magnetic pole width of probe .

Description

The method and the sensor thereof of the radial and axial displacement of a kind of synchro measure rotation axis

Technical field

The present invention relates to the method and the sensor thereof of the radial and axial displacement of a kind of synchro measure rotation axis, belong to sensor technology and gap or displacement measurement technical field.

Background technology

In some occasions that the vibration of high-speed rotating shaft is measured, usually require to carry out non-cpntact measurement, to avoid sensor probe infringement measured body surface.At present, the rotation axis non-cpntact measurement adopts eddy current displacement sensor or capacitance displacement sensor usually.Fig. 6 is in the prior art, with the electric vortex sensor measuring rotation axis axially and the structural representation of radial displacement.Sensor probe 15 is installed in the axle head of rotation axis 1, is used to measure rotation axis axial displacement.Sensor probe 14,16 symmetries are installed near the radial surface of rotation axis 1, are used to measure the displacement of a radial direction of rotation axis.If survey the displacement of another one radial direction, also need to install two with probe 2,4 one-tenth 90 sensor probes of spending angles.Obviously adopt the sensor construction of this mode will increase axial length, mounting structure is very complicated.And axially the measured sensor probe also may be because the radial position variation of rotation axis or the influence of expanding with heat and contract with cold, make measurement result not only reflect the variation of axial displacement, also be subjected to the influence of factors such as radial displacement variation, equally, the sensor probe of radial measurement also can be subjected to the influence of installation site deviation.These factors have all increased displacement measurement errors, even might jeopardize the safe operation of unit.Conventional eddy current displacement sensor and another shortcoming of capacitive transducer be, is subjected to electromagnetic interference (EMI) easily, and antijamming capability is relatively poor in rugged surroundings.Along with using more and more widely of magnetic suspension bearing, press for new axial displacement measuring method.

Summary of the invention

The objective of the invention is to propose the method and the sensor thereof of the radial and axial displacement of a kind of synchro measure rotation axis, change the structure of existing measurement mechanism, make simple and reliable for structurely, and improve antijamming capability, in rugged surroundings, can work stably in a long term.

The method of the radial and axial displacement of synchro measure rotation axis that the present invention proposes, non-magnetic conduction pressure ring at first is set on the lining of tested rotation axis, inlay rotor in the non-magnetic conduction pressure ring, stator casing of suit outside the lining of tested rotation axis, parallel first stator, second stator and the 3rd stator of being provided with in stator casing, be provided with pad between three stators, second stator is relative with described centre of rotor position, and stator and rotor constitute displacement measurement sensor.First stator and the 3rd stator are respectively the circle ring iron core that endless belt has dentation to pop one's head in, be wound with coil on the dentation probe, the dentation probe has 4 groups, 4 groups of dentations are popped one's head in along the interior ring circumference uniform distribution of circle ring iron core, in every group of probe 2 probes are arranged, every group the probe in coil press the self-induction type coiling, 4 groups of probe coils are connected successively, the coil between the first and the 3rd stator connects by differential mode; Second stator is the circle ring iron core that endless belt has the dentation probe in, be wound with coil on the dentation probe, the dentation probe has 4 groups, pop one's head in along the interior ring circumference uniform distribution of circle ring iron core for 4 groups, 4 dentation probes are arranged in every group of probe, coil during 4 dentations are popped one's head in is pressed self-induction type or mutual inductance type coiling, and the position connects by differential mode with the coil between the axle center two opposite groups probe.The dentation probe of second stator differs 45 ° with the dentation probe of the first, the 3rd stator along circumference.Then the axial displacement of rotation axis is: $\mathrm{\&Delta;z}=\frac{a_0\mathrm{\&Delta;<figure-callout\; id="4"\; label="Lz"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">Lz</figure-callout>}}{4{\mathrm{\&mu;}}_0{N_1}^{2}b},$ The radial displacement of rotation axis directions X is: $\mathrm{\&Delta;x}=-\frac{{a_0}^2\mathrm{\&Delta;Lx}}{{\mathrm{\&mu;}}_0{{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">N</figure-callout>}}_2}^2\mathrm{bc}},$ The radial displacement of Y direction is: $\mathrm{\&Delta;y}=-\frac{{a_0}^2\mathrm{\&Delta;Ly}}{{\mathrm{\&mu;}}_0{{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">N</figure-callout>}}_2}^2\mathrm{bc}},$ Wherein Δ Lz is first stator and the differential total variation (L that is connected the back inductance of the coil of the 3rd stator _Z1+ L _Z2+ L _Z3+ L _Z4)-(L _Z1'+L _Z2'+L _Z3'+L _Z4'), Δ Lx is that second stator is at the differential connection of directions X two opposite groups probe coil back variation inductance amount (L _X+-L _X-), Δ Ly is that second stator is at the differential connection of Y direction two opposite groups probe coil back variation inductance amount (L _Y+-L _Y-), Δ x is the radial displacement of rotation axis directions X when moving, and Δ y is the radial displacement of rotation axis Y direction when moving, and Δ z is the axial displacement of rotation axis when moving, μ ₀Be the air-gap permeance between first, second, third stator dentation probe and the rotor, N ₁Be the coil total number of turns of every group of probe of the first, the 3rd stator, N ₂Be the coil total number of turns of every group of probe of second stator, b is the facewidth of first, second, third stator dentation probe, the magnet pole widths of promptly popping one's head in, and c is the thickness of first, second, third stator, a ₀The radial play of rotation axis and sensor stator during for initial position.

Non-magnetic conduction pressure ring in the said method is made of aluminum or copper.The circle ring iron core of first stator, second stator and the 3rd stator is made by silicon steel or permalloy.

The sensor of the radial and axial displacement of synchro measure rotation axis that the present invention proposes comprises non-magnetic conduction pressure ring, rotor, first stator, second stator and the 3rd stator.Non-magnetic conduction pressure ring is placed on the lining of tested rotation axis, and described rotor is embedded in the non-magnetic conduction pressure ring.First stator, second stator and the 3rd stator are parallel successively to be placed in the sensor stator shell, is fixed by dog screw, is provided with pad between the stator, and second stator is relative with described centre of rotor.First stator and the 3rd stator are respectively the circle ring iron core that endless belt has dentation to pop one's head in, be wound with coil on the dentation probe, the dentation probe has 4 groups, 4 groups of dentations are popped one's head in along the interior ring circumference uniform distribution of circle ring iron core, in every group of probe 2～10 probes are arranged, every group the probe in coil press self-induction type or mutual inductance type coiling, 4 groups of probe coils are connected successively, the coil between the first and the 3rd stator connects by differential mode; Second stator is the circle ring iron core that endless belt has the dentation probe in, be wound with coil on the dentation probe, the dentation probe has 4 groups, pop one's head in along the interior ring circumference uniform distribution of circle ring iron core for 4 groups, 2～10 dentation probes are arranged in every group of probe, coil in the dentation probe is pressed self-induction type or mutual inductance type coiling, and the position connects by differential mode with the coil between the axle center two opposite groups probe; The dentation probe of described second stator differs 45 ° with the dentation probe of the first, the 3rd stator along circumference.

In the sensor, in every group of probe of first stator and the 3rd stator 2 probes are arranged, in every group of probe of second stator 4 probes are arranged.

The method and the sensor thereof of the radial and axial displacement of a kind of synchro measure rotation axis that the present invention proposes, telefault by radial arrangement radially carries out synchro measure and processing with an axial displacement signal to two, can simplify the installation of displacement transducer effectively, reduce measurement space, and this cell winding connects by differential mode, compensation temperature changes effectively, electromagnetic radiation, the common mode interference of external factor such as ground wire conduction to measuring, precision and the antijamming capability measured have been improved greatly, can realize the long Distance Transmission more than 100 meters, and the direct transmission range of the signal of current vortex sensor generally be no more than 10 surplus rice.Therefore, the sensor that the present invention proposes is applicable to some bad working environment, for example in the magnetic suspension bearing.

Description of drawings

Fig. 1 is the structural representation of sensor of the present invention.

Fig. 2 is the structural representation of the first and the 3rd stator in the sensor of the present invention.

Fig. 3 is the structural representation of second stator in the sensor of the present invention.

Fig. 4 is the A-A cut-open view of Fig. 1, to show the assembly relation of first stator, second stator and the 3rd stator.

Fig. 5 is the measuring principle figure of the inventive method, and wherein (a) is initial position, (b) is that rotation axis moves the position, back.

Fig. 6 be existing electric vortex sensor measuring rotation axis axially and the structural representation of radial displacement.

Among Fig. 1～Fig. 6,1 rotating shaft is a lining, the 2nd, and dog screw, the 3rd, the sensor stator shell, 4 is first stators, the 5th, pad, 6 is second stators, the 7th, and pad, 8 is the 3rd stators, the 9th, non-magnetic conduction pressure ring, the 10th, rotor, the 11st, rotating shaft, the 12nd, stator core, make by permeability magnetic materials such as silicon steel or permalloys, the 13rd, the coil of coiling on stator inner loop dentation probe, 14,15,16 is respectively the current vortex sensor probe in the existing measurement mechanism.B is the facewidth of the probe of the dentation on the ring in first, second, third stator core, i.e. Tan Tou magnet pole widths, and c is the transverse tooth thickness that the dentation on the ring is popped one's head in first, second, third stator core, a ₀For rotation axis when the initial position and the radial play of sensor stator, z ₀Two interfaces to the first during for initial position on the rotation axis and the distance of the 3rd stator inner side end, Δ x be rotating shaft when moving the radial play of directions X change, Δ y is that the radial play of rotating shaft Y direction when moving changes the displacement that Δ z moves for the Z direction.

Embodiment

The method of the radial and axial displacement of synchro measure rotation axis that the present invention proposes, non-magnetic conduction pressure ring at first is set on tested rotation axis, inlay rotor in the non-magnetic conduction pressure ring, stator casing of suit outside the lining of tested rotation axis, parallel first stator, second stator and the 3rd stator of being provided with in stator casing, be provided with pad between three stators, second stator is relative with described centre of rotor position, and stator and rotor constitute displacement measurement sensor.First stator and the 3rd stator are respectively the circle ring iron core that endless belt has dentation to pop one's head in, be wound with coil on the dentation probe, the dentation probe has 4 groups, 4 groups of dentations are popped one's head in along the interior ring circumference uniform distribution of circle ring iron core, in every group of probe 2 probes are arranged, every group the probe in coil press the self-induction type coiling, 4 groups of probe coils are connected successively, the coil between the first and the 3rd stator connects by differential mode; Second stator is the circle ring iron core that endless belt has the dentation probe in, be wound with coil on the dentation probe, the dentation probe has 4 groups, pop one's head in along the interior ring circumference uniform distribution of circle ring iron core for 4 groups, 4 dentation probes are arranged in every group of probe, coil during 4 dentations are popped one's head in is pressed self-induction type or mutual inductance type coiling, and the position connects by differential mode with the coil between the axle center two opposite groups probe.The dentation probe of second stator differs 45 ° with the dentation probe of the first, the 3rd stator along circumference.Then the axial displacement of rotation axis is: $\mathrm{\&Delta;z}=\frac{a_0\mathrm{\&Delta;<figure-callout\; id="4"\; label="Lz"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">Lz</figure-callout>}}{4{\mathrm{\&mu;}}_0{N_1}^{2}b},$ The radial displacement of rotation axis directions X is: $\mathrm{\&Delta;x}=-\frac{{a_0}^2\mathrm{\&Delta;Lx}}{{\mathrm{\&mu;}}_0{{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">N</figure-callout>}}_2}^2\mathrm{bc}},$ The radial displacement of Y direction is: $\mathrm{\&Delta;y}=-\frac{{a_0}^2\mathrm{\&Delta;Ly}}{{\mathrm{\&mu;}}_0{{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">N</figure-callout>}}_2}^2\mathrm{bc}},$ Wherein Δ Lz is first stator and the differential total variation (L that is connected the back inductance of the coil of the 3rd stator _Z1+ L _Z2+ L _Z3+ L _Z4)-(L _Z1'+L _Z2'+L _Z3'+L _Z4'), Δ Lx is that second stator is at the differential connection of directions X two opposite groups probe coil back variation inductance amount (L _X+-L _X-), Δ Ly is that second stator is at the differential connection of Y direction two opposite groups probe coil back variation inductance amount (L _Y+-L _Y-), Δ x is the radial displacement of rotation axis directions X when moving, and Δ y is the radial displacement of rotation axis Y direction when moving, and Δ z is the axial displacement of rotation axis when moving, μ ₀Be the air-gap permeance between first, second, third stator dentation probe and the rotor, N ₁Be the coil total number of turns of every group of probe of the first, the 3rd stator, N ₂Be the coil total number of turns of every group of probe of second stator, b is the facewidth of first, second, third stator dentation probe, the magnet pole widths of promptly popping one's head in, and c is the thickness of first, second, third stator, a ₀The radial play of rotation axis and sensor stator during for initial position.

Non-magnetic conduction pressure ring in the said method is made of aluminum or copper.The circle ring iron core of first stator, second stator and the 3rd stator is made by silicon steel or permalloy.

The sensor of the radial and axial displacement of synchro measure rotation axis that the present invention proposes, its structure comprises non-magnetic conduction pressure ring 9, rotor 10, first stator 4, second stator 6 and the 3rd stator 8 as shown in Figure 1.Non-magnetic conduction pressure ring 9 is placed on the lining 1 of tested rotation axis, and described rotor 10 is embedded in the non-magnetic conduction pressure ring 9.First stator 4, second stator 6 and the 3rd stator 8 are parallel successively to be placed in the sensor stator shell 3, and fixing by dog screw 2, it is relative with the center of described rotor 10 with 7, the second stators 6 to be provided with pad 5 between the stator.The structure of first stator 4 and the 3rd stator 6 as shown in Figure 2, be respectively the circle ring iron core 12 that endless belt has dentation to pop one's head in, be wound with coil 13 on the dentation probe, the dentation probe has 4 groups, 4 groups of dentations probe has 2～10 probes along the interior ring circumference uniform distribution of circle ring iron core in every group of probe, and the coil in every group of probe is pressed self-induction type or mutual inductance type coiling, 4 groups of probe coils are connected successively, and the coil between the first and the 3rd stator connects by differential mode.The structure of second stator 6 as shown in Figure 3, it is the circle ring iron core that endless belt has the dentation probe in, be wound with coil on the dentation probe, the dentation probe has 4 groups, pop one's head in along the interior ring circumference uniform distribution of circle ring iron core for 4 groups, 2～10 dentation probes are arranged in every group of probe, and the coil in the dentation probe is pressed self-induction type or mutual inductance type coiling, and the position connects by differential mode with the coil between the axle center two opposite groups probe.The dentation probe of second stator differs 45 ° with the dentation probe of the first, the 3rd stator along circumference, as shown in Figure 4.

In one embodiment of the present of invention, in every group of probe of first stator and the 3rd stator 2 probes are arranged, as shown in Figure 2, in every group of probe of second stator 4 probes are arranged, as shown in Figure 3.

In the sensor, constitute the circle ring iron core 12 of first stator, second stator and the 3rd stator, can make with permeability magnetic materials such as higher silicon steel of magnetoconductivity or permalloys.Every group the probe in coil 13 press the self-induction type coiling.4 groups of probe coils on the first and the 3rd stator are series connection successively respectively, between two stators coil is connected by differential mode.In 4 groups of probe coils on second stator, the coil between the two opposite groups probe connects by differential mode respectively.

Fig. 5 is the measuring principle figure of the inventive method, only indicated among the figure radially directions X and axial Z direction, and Y direction radially and X, Z angular separation respectively are 90 degree, fail to mark in Fig. 5.Introduce the measuring principle of the inventive method below in conjunction with accompanying drawing 5:

Lz1 is the inductance value of first stator 4+directions X probe among Fig. 5, Lz ₃Be first stator 4-inductance value of directions X probe, Lz ₁' be the 3rd stator 8+inductance value of directions X probe, Lz ₃' be the 3rd stator 8-inductance value of directions X probe, Lx-be second stator 6-inductance value of directions X probe, Lx+ be second stator 6+inductance value of directions X probe.a ₀For rotation axis when the initial position and the radial play of sensor stator, z ₀The distance of two interfaces to the first during for initial position on the rotation axis, the 3rd sensor stator (4,8) inner side end.Δ x is that the rotating shaft radial play that directions X makes progress when moving changes, i.e. X radial displacement, and Δ y is that the rotating shaft radial play that the Y direction makes progress when moving changes i.e. Y radial displacement, the distance that Δ z is moved to the left for the Z direction, the i.e. displacement of Z direction.

When rotation axis 1 was positioned at initial position shown in Figure 5, promptly two of rotor sensor 10 interfaces laid respectively at the center of two stator core end faces.When not moving radially, because first and the 3 two stator form by the equally distributed 4 groups of inductance of connecting successively of circumferential 90 degree respectively, change and do not have when moving axially when rotating shaft produces radial play, the total inductance value remains unchanged, thereby two sensor stator coils are output as 0 after differential.Simultaneously, in 4 groups of probe coils on second stator, the coil between the two opposite groups probe connects by differential mode respectively, thereby output also is 0.

When the radial and axial position of rotation axis changed, two interfaces on the rotation axis and the relative position of three sensor stators changed, and made the inductance value of three sensor stators 4,6 and 8 all change.

According to the inductance principle, at directions X, if radial play is changed to Δ x, rotating shaft is moved to the left distance and is Δ z, then has:

First stator is in the inductance value of+directions X probe: $L_{z1}=\frac{{\mathrm{\&mu;}}_0{N_1}^{2}b(z_0+\mathrm{\&Delta;z})}{2(a_0+\mathrm{\&Delta;x}/\sqrt{2})}$

First stator is in the inductance value of-directions X probe: ${\mathrm{<figure-callout\; id="3"\; label="L\; z"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">L</figure-callout>}}_z=\frac{{\mathrm{\&mu;}}_0{N_1}^{2}b(z_0+\mathrm{\&Delta;z})}{2(a_0-\mathrm{\&Delta;x}/\sqrt{2})}$

Second stator is in the inductance value of+directions X probe: ${L_{z1}}^{\&prime;}=\frac{{\mathrm{\&mu;}}_0{N_1}^{2}b(z_0+\mathrm{\&Delta;z})}{2(a_0+\mathrm{\&Delta;x}/\sqrt{2})}$

Second stator is in the inductance value of-directions X probe: ${{\mathrm{<figure-callout\; id="3"\; label="L\; z"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">L</figure-callout>}}_z}^{\&prime;}=\frac{{\mathrm{\&mu;}}_0{N_1}^{2}b(z_0-\mathrm{\&Delta;z})}{2(a_0-\mathrm{\&Delta;x}/\sqrt{2})}$

When radial play variation range delta x hour, can get: $(L_{z1}+L_{z3})-({L_{z1}}^{\&prime;}+{{\mathrm{<figure-callout\; id="3"\; label="L\; z"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">L</figure-callout>}}_z}^{\&prime;})=\frac{{2\mathrm{\&mu;}}_0{N_1}^2\mathrm{b\&Delta;z}}{a_0}$

In like manner, in the Y directions that becoming 90 degree with X, when radial play variation range delta y hour, mathematical derivation can get:

$(L_{z2}+L_{z4})-({L_{z2}}^{\&prime;}+{L_{z4}}^{\&prime;})=\frac{{2\mathrm{\&mu;}}_0{N_1}^2\mathrm{b\&Delta;z}}{a_0}$

Therefore, first stator and the differential total variation that is connected the back inductance value of second stator coil:

$\mathrm{\&Delta;L}=(L_{z1}+L_{z2}+L_{z3}+L_{z4})-({L_{z1}}^{\&prime;}+{L_{z2}}^{\&prime;}+{L_{z3}}^{\&prime;}+{L_{z4}}^{\&prime;})=\frac{{4\mathrm{\&mu;}}_0{N_1}^2\mathrm{b\&Delta;z}}{a_0}$ That is:

$\mathrm{\&Delta;z}=\frac{a_0\mathrm{\&Delta;<figure-callout\; id="4"\; label="L"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">L</figure-callout>}}{{4\mathrm{\&mu;}}_0{N_1}^{2}b}$

Δ L is the differential total variation that is connected the back inductance value of first stator and the 3rd stator coil in the formula, and Δ z is the rotation axis distance that the Z direction is moved to the left when moving, μ ₀Be air-gap permeance, N ₁Be the coil total number of turns of every group of first stator and the 3rd stator probe, b is that endless belt has the dentation probe facewidth in the sensor stator, i.e. Tan Tou magnet pole widths, a ₀For rotation axis when the initial position and the radial play of sensor stator.

In like manner, second stator is in the inductance value of+directions X probe: $L_{x+}=\frac{{\mathrm{\&mu;}}_0{{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">N</figure-callout>}}_2}^2\mathrm{bc}}{2(a_0+\mathrm{\&Delta;x})}$

Second stator is in the inductance value of-directions X probe: $L_{x-}=\frac{{\mathrm{\&mu;}}_0{{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">N</figure-callout>}}_2}^2\mathrm{bc}}{2(a_0-\mathrm{\&Delta;x})}$

Second stator is in the inductance value of+Y direction probe: $L_{y+}=\frac{{\mathrm{\&mu;}}_0{{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">N</figure-callout>}}_2}^2\mathrm{bc}}{2(a_0+\mathrm{\&Delta;y})}$

Second stator is in the inductance value of-Y direction probe: $L_{x+}=\frac{{\mathrm{\&mu;}}_0{{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">N</figure-callout>}}_2}^2\mathrm{bc}}{2(a_0-\mathrm{\&Delta;y})}$

When radial play variation range delta x and Δ y hour, can get:

$\mathrm{\&Delta;x}=\frac{{a_0}^2(L_{x+}-L_{x-})}{{\mathrm{\&mu;}}_0{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">N</figure-callout>}}^2\mathrm{bc}}=-\frac{{a_0}^2\mathrm{\&Delta;Lx}}{{\mathrm{\&mu;}}_0{{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">N</figure-callout>}}_2}^2\mathrm{bc}}$

$\mathrm{\&Delta;y}=\frac{{a_0}^2(L_{y+}-L_{y-})}{{\mathrm{\&mu;}}_0{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">N</figure-callout>}}^2\mathrm{bc}}=\frac{{a_0}^2\mathrm{\&Delta;Ly}}{{\mathrm{\&mu;}}_0{{\mathrm{<figure-callout\; id="2"\; label="N"\; filenames="A20061006494000101.png"\; state="\{\{state\}\}">N</figure-callout>}}_2}^2\mathrm{bc}},$

Δ Lx is the variation inductance amount (L after the differential connection of directions X two opposite groups probe coil of second stator in the formula _X+-L _X-), Δ Ly is the variation inductance amount (L after the differential connection of Y direction two opposite groups probe coil of second stator _Y+-L _Y-), Δ x is the radial displacement of rotation axis directions X when moving, Δ y is the radial displacement of rotation axis Y direction when moving, μ ₀Be the profile of tooth probe of stator and the air-gap permeance between the rotor, N ₂Be the coil total number of turns of every group of probe of second stator, b is the facewidth of stator inner loop dentation probe, the magnet pole widths of promptly popping one's head in, and c is the thickness of stator, a ₀For rotation axis when the initial position and the radial play of sensor stator.

Following formula clearly illustrates that, the inductance of directions X two opposite groups probe coil after differential is output into linear dependence on the radial displacement Δ x and second stator, and with Δ y, Δ z is irrelevant.The inductance of Y direction two opposite groups probe coil after differential is output into linear dependence on the radial displacement Δ y and second stator, and with Δ x, Δ z is irrelevant.The inductance of coil after differential is output into linear relationship on axial displacement z and first, the 3rd stator 4 and 8, and with radial displacement Δ x, Δ y is irrelevant, thereby realized the synchro measure of footpath axial displacement.

Claims (5)

1, the method for the radial and axial displacement of a kind of synchro measure rotation axis, it is characterized in that this method is provided with non-magnetic conduction pressure ring on tested rotation axis, inlay rotor in the non-magnetic conduction pressure ring, stator casing of suit outside the lining of tested rotation axis, parallel first stator, second stator and the 3rd stator of being provided with in stator casing, be provided with pad between three stators, second stator is relative with described centre of rotor position, and stator and rotor constitute displacement measurement sensor; Described first stator and the 3rd stator are respectively the circle ring iron core that endless belt has dentation to pop one's head in, be wound with coil on the dentation probe, the dentation probe has 4 groups, 4 groups of dentations are popped one's head in along the interior ring circumference uniform distribution of circle ring iron core, in every group of probe 2 probes are arranged, every group the probe in coil press the self-induction type coiling, 4 groups of probe coils are connected successively, the coil between the first and the 3rd stator connects by differential mode; Second stator is the circle ring iron core that endless belt has the dentation probe in, be wound with coil on the dentation probe, the dentation probe has 4 groups, pop one's head in along the interior ring circumference uniform distribution of circle ring iron core for 4 groups, 4 dentation probes are arranged in every group of probe, coil during 4 dentations are popped one's head in is pressed self-induction type or mutual inductance type coiling, and the position connects by differential mode with the coil between the axle center two opposite groups probe; The dentation probe of described second stator differs 45 ° with the dentation probe of the first, the 3rd stator along circumference, and then the axial displacement of rotation axis is: $\mathrm{\&Delta;z}=\frac{a_0\mathrm{\&Delta;Lz}}{4{\mathrm{\&mu;}}_0{N_1}^{2}b},$ The radial displacement of rotation axis directions X is: $\mathrm{\&Delta;x}=-\frac{{a_0}^2\mathrm{\&Delta;Lx}}{{\mathrm{\&mu;}}_0{N_2}^2\mathrm{bc}},$ The radial displacement of Y direction is: $\mathrm{\&Delta;y}=-\frac{{a_0}^2\mathrm{\&Delta;Ly}}{{\mathrm{\&mu;}}_0{N_2}^2\mathrm{bc}},$ Wherein Δ Lz is first stator and the differential total variation (L that is connected the back inductance of the coil of the 3rd stator _Z1+ L _Z2+ L _Z3+ L _Z4)-(L _Z1'+L _Z2'+L _Z3'+L _Z4'), Δ Lx is that second stator is at the differential connection of directions X two opposite groups probe coil back variation inductance amount (L _X+-L _X-), Δ Ly is that second stator is at the differential connection of Y direction two opposite groups probe coil back variation inductance amount (L _Y+-L _Y-), Δ x is the radial displacement of rotation axis directions X when moving, and Δ y is the radial displacement of rotation axis Y direction when moving, and Δ z is the axial displacement of rotation axis when moving, μ ₀Be the air-gap permeance between first, second, third stator dentation probe and the rotor, N ₁Be the coil total number of turns of every group of probe of the first, the 3rd stator, N ₂Be the coil total number of turns of every group of probe of second stator, b is the facewidth of first, second, third stator dentation probe, the magnet pole widths of promptly popping one's head in, and c is the thickness of first, second, third stator, a ₀The radial play of rotation axis and sensor stator during for initial position.

2, the method for claim 1 is characterized in that wherein said non-magnetic conduction pressure ring is made of aluminum or copper.

3, the method for claim 1 is characterized in that the circle ring iron core of wherein said first stator, second stator and the 3rd stator is made by silicon steel or permalloy.

4, the sensor of the radial and axial displacement of a kind of synchro measure rotation axis is characterized in that this sensor comprises non-magnetic conduction pressure ring, rotor, first stator, second stator and the 3rd stator; Described non-magnetic conduction pressure ring is placed on the lining of tested rotation axis, and described rotor is embedded in the non-magnetic conduction pressure ring; Described first stator, second stator and the 3rd stator are parallel successively to be placed in the sensor stator shell, is fixed by dog screw, is provided with pad between the stator, and second stator is relative with described centre of rotor; Described first stator and the 3rd stator are respectively the circle ring iron core that endless belt has dentation to pop one's head in, be wound with coil on the dentation probe, the dentation probe has 4 groups, 4 groups of dentations are popped one's head in along the interior ring circumference uniform distribution of circle ring iron core, in every group of probe 2～10 probes are arranged, every group the probe in coil press self-induction type or mutual inductance type coiling, 4 groups of probe coils are connected successively, the coil between the first and the 3rd stator connects by differential mode; Second stator is the circle ring iron core that endless belt has the dentation probe in, be wound with coil on the dentation probe, the dentation probe has 4 groups, pop one's head in along the interior ring circumference uniform distribution of circle ring iron core for 4 groups, 2～10 dentation probes are arranged in every group of probe, coil in the dentation probe is pressed self-induction type or mutual inductance type coiling, and the position connects by differential mode with the coil between the axle center two opposite groups probe; The dentation probe of described second stator differs 45 ° with the dentation probe of the first, the 3rd stator along circumference.

5, sensor as claimed in claim 4 is characterized in that in every group of probe of wherein said first stator and the 3rd stator 2 probes being arranged, and in every group of probe of second stator 4 probes is arranged.

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