RU2328348C1 - Vertical rotor magnetic support - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: vertical rotor magnetic support incorporates an annular magnet arranged in the case, a ferromagnetic shell arranged on the rotor opposite to the bottom end face of a magnet, and a rotor r.p.m. pickup. Note, that the said pickup is arranged in an axial gap between the magnet lower end face and the shell upper end face.

EFFECT: ruling out disturbances asymmetric relative the rotor rotation axis and out-of-the-case pickup arrangement without complicating the support design.

11 cl, 6 dwg

Description

The invention relates to mechanical engineering and mainly to the magnetic supports of vertical rotors of rapidly rotating devices, gyroscopes, energy stores, generators, turbomolecular pumps, centrifuges. The invention relates mainly to multifunctional magnetic supports in which the upper magnetic support of the rotor not only unloads the lower support from axial load, but also provides radial rigidity and centering of the rotor relative to the housing, and also creates a magnetic field in which the sensors are installed to determine parameters of a rotating rotor.

A technical solution is known (RF Patent: RU 2180435, G01M 1/22, V04V 9/14, 11/05/1999), in which the plate inductor located in the magnetic field of the support interacts with the sensor in the form of an inductive coil fixedly mounted near it and induces an alternating coil in it current in the form of a signal, the processing of which allows you to select information about the speed of rotation and radial or axial movements of the rotor.

Placing a plate inductor on a rapidly rotating rotor creates problems of compatibility of its deformations with other parts of the rotor and ensuring the strength of the inductor.

Known magnetic support of the vertical rotor, adopted for the prototype, which contains a ferromagnetic sleeve mounted coaxially on the rotor, an annular axially magnetized magnet mounted in the housing above the sleeve, and a pole tip in the form of a ring with a radial shelf at the end adjacent to the lower end of the magnet. The ferromagnetic sleeve is made with an annular radial protrusion at the upper end of the sleeve and a radial limb, which acts as an inductor, at the lower end of the sleeve (RF Patent RU 2054334, V04V 9/12, 11.11.1992).

This invention increases the rigidity of the magnetic support and reduces the pressure on the lower support. At the same time, located near the radial bend of the lower end of the sleeve, the inductive coil senses changes in the magnetic flux in the magnetic support during rotation and oscillations of the rotor and is used to determine its parameters.

A disadvantage of the known solution is that the one-sided arrangement of the sensor causes an asymmetric load on the rotor, which can be significant in the magnetic supports of the rotors of sensitive instruments. In addition, the sensor that senses changes in the magnetic field during rotation of the rotor is located in the internal cavity with a rotating rotor, which can be exposed to aggressive dust and gas environments and elevated temperatures, which prevents free access to the sensor without opening the internal cavity of the housing.

The problem to which the invention is directed is to create a multifunctional upper magnetic support of the rotor with a speed sensor that does not create disturbances asymmetric about the axis of rotation of the rotor and is removed from the internal cavity of the rotor housing without complicating the design of the support.

To do this, in the magnetic support of the vertical rotor, which includes an annular magnet installed in the housing, a ferromagnetic sleeve located on the rotor opposite the lower end of the magnet, and a sensor for measuring the rotor speed, the sensor is installed in the axial clearance between the lower end of the magnet and the upper end of the sleeve.

Additionally, the sensor is installed outside the housing.

In addition, a pole piece of ferromagnetic material is mounted on the lower end of the magnet.

Additionally, the upper end of the sleeve is made in the form of a ring gear.

Additionally, the envelope of the ring gear has a sinusoid shape.

Additionally, the depth of the depressions of the ring gear is 0.01-0.03 of the average diameter of the upper end of the sleeve.

Additionally, the height of one tooth of the crown is 0.4-0.9 of the height of the remaining teeth.

Additionally, the sensor element is made in the form of an inductor.

Additionally, the sensor is made of a series of inductors connected in series, shifted in a circular direction from one another by an angle multiple of the angle of alternation of the teeth of the crown.

Additionally, the number of turns of at least one of the coils is 5-50% different from the number of turns of other coils.

Additionally, the sensor is made in the form of a plate with coils, for example, thermosetting resin, fixed in it.

The invention is illustrated by drawings:

figure 1 is a longitudinal section of a magnetic support of a vertical rotor with a sensor in the inner cavity of the housing;

figure 2 is a longitudinal section of a magnetic support of a vertical rotor with a sensor outside the housing;

figure 3 is an embodiment of a support with a pole tip and with a sleeve with a ring gear;

4 is an embodiment of a sensor with an inductor;

5 is an embodiment of a support with a sensor of several inductors;

6 is an embodiment of a sensor with several inductors.

The magnetic support of the vertical rotor contains an annular axially magnetized magnet 1 mounted on a non-magnetic cover 2 of the housing 3 (Fig. 1), a ferromagnetic sleeve 4 mounted on the rotor 5 coaxially with it in its upper part and located opposite the lower end of the magnet 1 with pole S. The rotor 5 rests on the lower support 6, and in the upper magnetic support does not have mechanical contact with stationary parts. A speed measuring sensor 7 is installed in the internal cavity of the housing 3 under the cover 2 in the axial clearance between the lower end of the magnet 1 and the upper end of the sleeve 4. The terminals 8 of the sensor through the sealing sleeve 9 in the cover 2 pass from the internal cavity of the housing 3 for connection with recording devices.

In an embodiment of the magnetic support (Fig. 2), the sensor 7 is removed from the internal cavity of the housing 3 and mounted on the cover 2 under the magnet 1.

In another embodiment of the magnetic support (Fig. 3), a pole piece 10 is mounted on the lower end of the magnet 1. A sensor 7 is located between the lower end of the tip 10 and the upper end of the sleeve 4. The upper end of the sleeve 4 is made in the form of a ring gear. The envelope 11 of the ring gear is in the form of a sinusoid with six depressions with a depth H from the upper end of the sleeve 4. The depth of the depressions H of the ring gear is 0.01-0.03 of the average diameter of the upper end of the sleeve, so that the relation H = (0.01- 0.03) (D + d) / 2, where

D is the outer diameter of the upper end of the sleeve;

d is the inner diameter of the upper end of the sleeve.

The height h of the tooth 12 is made smaller than the height H of the remaining five teeth 13, so that the relation h = (0.4-0.9) N is satisfied.

The sensitive element of the sensor 7 (figure 4) is made in the form of an inductor 14 located in the plate, and has conclusions 8.

The sensor 15 (Fig. 5 and Fig. 6) is made in the form of a plate with a series of inductively connected conductors 16 of inductive coils 17, 18, and 19 fixed in it, displaced in a circular direction from each other by an angle of 120 °, a multiple of the angle of alternation of six teeth of the crown . Moreover, the coil 19 is made with excellent by 5-50% from the coils 17 and 18 the number of turns. Coils are fixed in an annular plate.

Magnetic support works as follows.

At rest and during rotation of the rotor 5, the axisymmetric magnetic field of magnet 1 holds the ferromagnetic sleeve 4 and the associated rotor 5 in a vertical position, without interfering with the rotation of the rotor 5 on the support 6. If the rotor deviates from the axis of the housing 3, the symmetry of the magnetic field is violated, which creates radial force that prevents the deflection of the rotor 5 and returns the rotor 5 to its original position upon termination of the disturbing force.

The sensor 7, located inside the housing 3 (figure 1) in the magnetic flux in the gap between the magnet 1 and the sleeve 4, responds to changes in this magnetic flux that occur during rotation of the rotor 5 and when it deviates from the axis of rotation. The signal from the sensor 7 through the sealing sleeve 9 is fed to pin 8.

The sensor 7, located outside the housing 3 (figure 2) in the magnetic flux in the gap between the magnet 1 and the sleeve 4, responds to changes in this magnetic flux that occur during rotation of the rotor 5 and when it deviates from the axis of rotation. The signal from the sensor 7 is directly fed to pin 8.

A sensor 7 located outside the housing 3 (Fig. 3) in the magnetic flux, in the gap between the magnet, the pole piece 10 and the sleeve 4, responds to changes in the denser magnetic flux generated by the pole piece 10 that occur when the rotor 5 rotates and when deflected it from the axis of rotation. A more powerful signal from the sensor 7 is directly fed to pin 8, which increases the sensitivity of the sensor.

A further increase in the sensitivity of the sensor 7 is provided by the implementation of the upper end of the sleeve 4 in the form of a ring gear with an envelope 11 in the form of a sinusoid. Moreover, the implementation of the depth of the valleys of the gear rim, comprising 0.01-0.03 of the average diameter of the upper end of the sleeve 4, allows you to provide the best combination of the magnitude of the lifting force of the magnetic support, its radial stiffness and an acceptable value received from the sensor 7 of the signal.

When the rotor 5 is rotated, the peaks and valleys of the sine wave envelope 11 of the ring gear, passing under the sensor 7, create faster changes in the magnetic flux, as a result of which the signal value of the sensor 7 increases and its sensitivity increases. In addition, the frequency of the signal of the sensor 7 increases by a multiple of the number of teeth, which facilitates the processing of the signal of the sensor 7 in the recording device. And when you perform the height of one tooth 12 of the crown, which is 0.4-0.9 of the height of the remaining teeth 13, the signal coming from the sensor 7 becomes attached to the phase of rotation of the rotor 5, which, when processing the signal, allows you to determine not only the rotation speed and amplitude deviations of the rotor 5 from the axis of rotation, but also the position of the rotor 5 in space at any time.

When performing the sensitive element of the sensor 7 in the form of a flat inductor 14 with a small number of turns fixed to the plate with a thermosetting resin (figure 4), the design of the sensor and the magnetic support is greatly simplified. The increase in sensitivity in this design is ensured by the implementation of the sensor 15 (Fig.6) with sensitive elements from a series of 16 inductors 17, 18, 19 in series connected by conductors, displaced in a circular direction from each other by an angle of 120 °, a multiple of the angle of alternation of six teeth of the crown, as a result, the signal from the coils is summed up at terminals 8. Moreover, to distinguish the phase of rotation of the rotor 5 from the signal of such a sensor 15, the number of turns of the coil 19 is 5-50% different from the number of turns of other coils 17 and 18, which allows the magnitude of the signal at pins 8 is the position of the tooth 12 with a lower tooth height relative to the sensor coils.

Claims (11)

1. The magnetic support of the vertical rotor, including an annular magnet installed in the housing, a ferromagnetic sleeve located on the rotor opposite the lower end of the magnet, and a rotor speed measuring sensor, characterized in that the sensor is installed in the axial clearance between the lower end of the magnet and the upper end of the sleeve . 2. The magnetic support of the vertical rotor according to claim 1, characterized in that the sensor is installed outside the housing. 3. The magnetic support of the vertical rotor according to claim 1, characterized in that a pole piece of ferromagnetic material is installed on the lower end of the magnet. 4. The magnetic support of the vertical rotor according to any one of claims 1 to 3, characterized in that the upper end of the sleeve is made in the form of a ring gear. 5. The magnetic support of the vertical rotor according to claim 4, characterized in that the envelope of the ring gear has a sinusoid shape. 6. The magnetic support of the vertical rotor according to claim 5, characterized in that the depth of the depressions of the ring gear is 0.01-0.03 of the average diameter of the upper end of the sleeve. 7. The magnetic support of the vertical rotor according to claim 5, characterized in that the height of one tooth of the crown is 0.4-0.9 of the height of the remaining teeth. 8. The magnetic support of the vertical rotor according to any one of claims 1 to 3, characterized in that the sensor element is made in the form of an inductor. 9. The magnetic support of the vertical rotor of claim 8, characterized in that the sensor is made of a series of inductors connected in series, shifted in a circular direction from one another by an angle multiple of the angle of alternation of the teeth of the crown. 10. The magnetic support of the vertical rotor according to claim 9, characterized in that the number of turns of at least one of the coils is 5-50% different from the number of turns of other coils. 11. The magnetic support of the vertical rotor according to claim 8, characterized in that the sensor is made in the form of a plate with coils fixed therein, for example, with a thermosetting resin.

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