Method for actively balancing a rotor, and device comprising a rotor and a mechanism paired with the rotor for actively balancing same

Patent metadata

Field	Value
Publication number	US-12449017-B2
Application number	US-202017785714-A
Country	US
Kind code	B2
Filing date	Dec 11, 2020
Priority date	Dec 16, 2019
Publication date	Oct 21, 2025
Grant date	Oct 21, 2025

Abstract

The invention relates to a method for actively balancing a rotor ( 1 ), comprising: providing a device with a rotor ( 1 ) that can be rotated around an axis of rotation and a mechanism ( 2 ) allocated to the rotor ( 1 ) for actively balancing, in which a magnetic fluid ( 7 ) is received in a fluid chamber ( 6 ) formed on the rotor ( 1 ), which partially fills the fluid chamber ( 6 ) and contains at least one of the following fluids: ferrofluid and magnetorheological fluid; holding the magnetic fluid ( 7 ) by means of a permanent magnetic field of a permanent magnet ( 5 ) arranged on the rotor ( 1 ) in an initial position in the fluid chamber ( 6 ); rotating the rotor ( 1 ) around the axis of rotation ( 3 ), and passing the fluid chamber ( 6 ) and permanent magnet ( 5 ) by an electrical exciter system with a fixedly arranged electromagnet ( 8 ) during the rotation of the rotor ( 1 ), wherein the permanent magnetic field of the permanent magnet ( 5 ) and an electromagnetic field of the electromagnet ( 8 ) here overlap in an activated state for active balancing purposes, so that the magnetic fluid ( 7 ) in the fluid chamber ( 6 ) performs a mass displacement proceeding from the initial position. Also created is a device with a rotor ( 1 ) and a mechanism ( 2 ) allocated to the rotor ( 1 ) for actively balancing the rotor ( 1 ).

First claim

The invention claimed is:

1. A method for actively balancing a rotor comprising:
providing a device with a rotor rotatable around an axis of rotation and a mechanism configured to actively balance the rotor, in which a magnetic fluid is received in a fluid chamber formed on the rotor, which partially fills the fluid chamber and contains at least one of the following fluids: ferrofluid and magnetorheological fluid;
holding the magnetic fluid by means of a permanent magnetic field of a permanent magnet arranged on the rotor in an initial position in the fluid chamber;
rotating the rotor around the axis of rotation, wherein several segmented areas are formed on the rotor, which each consist of an assigned permanent magnet and an assigned fluid chamber with magnetic fluid; and
passing the fluid chamber and the permanent magnet by an electrical exciter system with a fixedly arranged electromagnet during the rotation of the rotor, wherein the permanent magnetic field of the permanent magnet and an electromagnetic field of the electromagnet here overlap in an activated state for active balancing purposes, so that the magnetic fluid in the fluid chamber performs a mass displacement proceeding from the initial position.

2. The method according to claim 1 , characterized in that the magnetic fluid is shifted in at least one of the following directions during mass displacement: radial direction and tangential direction.

3. The method according to claim 1 , characterized in that the magnetic fluid performs the mass displacement based upon a radial acceleration, which acts on the magnetic fluid during the rotation of the rotor.

4. The method according to claim 1 , characterized in that, during the rotation of the rotor, the magnetic fluid performs the mass displacement based upon a resulting magnetic field, which arises due to the overlap of the permanent magnetic field and the electromagnetic field.

5. The method according to claim 1 , characterized in that, due to the mass displacement of the magnetic fluid during the rotation of the rotor, at least one of the following mass balancing processes is performed: a positive mass balancing and negative mass balancing.

6. The method according to claim 1 , characterized in that the fluid chamber is partially filled with a magnetic fluid, which consists of the magnetorheological fluid.

7. The method according to claim 1 , characterized in that the magnetic fluid in the fluid chamber flows back if a rotational speed of the rotation of the rotor is reduced.

8. The method according to claim 1 , characterized in that the magnetic fluid
is held by means of the permanent magnetic field in the initial position on an inner side of the fluid chamber lying inside in radial direction; and
during the rotation of the rotor for active balancing purposes, is displaced from the inner side partially towards an outer side of the fluid chamber lying outside in radial direction.

9. The method according to claim 1 , characterized in that, during the rotation of the rotor, a change is be made between various stable system states, which each are maintained by means of the permanent magnetic field of the permanent magnet and/or the radial acceleration acting on the magnetic fluid, wherein the various stable system states have a respectively different distribution of the mass of the magnetic fluid in the fluid chamber.

10. The method according to claim 1 , characterized in that the permanent magnet is formed on the rotor by means of a ring magnet.

11. The method according to claim 1 , characterized in that the electrical exciter system is formed with several electromagnets, which each are oppositely and fixedly arranged in relation to the rotor, and past which the fluid chamber is guided during the rotation of the rotor, such that the permanent magnetic field and the electromagnetic field of the electromagnet each overlap in an activated state for active balancing purposes.

12. A device with a rotor and a mechanism assigned to the rotor for actively balancing the rotor, further comprising:
an axis of rotation around which the rotor is rotatable;
a fluid chamber that is arranged on the rotor, wherein several segmented areas are formed on the rotor, which each consist of an assigned permanent magnet and an assigned fluid chamber with magnetic fluid;
a magnetic fluid, which partially fills the fluid chamber and contains at least one of the following fluids: ferrofluid and magnetorheological fluid;
a permanent magnet, which is arranged on the rotor and configured to hold the magnetic fluid in an initial position in the fluid chamber by means of a permanent magnetic field; and
an electrical exciter system with a fixedly arranged electromagnet, such that, during the rotation of the rotor, when the fluid chamber and the permanent magnet are bypassable the electromagnet, the permanent magnetic field of the permanent magnet and an electromagnetic field of the electromagnet overlap in the activated state for active balancing purposes, so that the magnetic fluid in the fluid chamber can perform a mass displacement proceeding from the initial position.

Assignees

• Univ Berlin Tech

Inventors

• Schreiner Valentin
• Hegger Christian
• Maas Jürgen

Classifications

• F16F2232/02

  Rotary · CPC title

• F16F2230/0011

  Balancing, e.g. counterbalancing to produce static balance · CPC title

• F16F2224/045

  magnetorheological · CPC title

• F16F2222/06

  Magnetic or electromagnetic · CPC title

• F16F15/18

  using electric, {magnetic or electromagnetic} means ({suppression of vibrations of rotating systems by use of non-rotating magnetic or electromagnetic means F16F15/03;} dynamo-electric devices H02K; {control effected upon generator excitation circuit to reduce harmful effects of overloads or transients H02P9/10}) · CPC title