DE2455355A1 - Electro magnetic rotary stiffening element of variable rigidity - has pairs of pole pieces in an annular configuration with air gaps which conductors can be moved - Google Patents

Abstract

An electromagnetic rotary stiffening element of variable rigidity has a magnetic field which is applied to a conductor through which an electric current is flowing and has at least two pole pairs on a pref. annular configuration with air gaps between opposite pole pieces. In the air gaps between the pole pieces of opposite polarity a movable conductor can be mounted which has an electrical current flowing through it in such a direction that on movement of the conductor from the neutral zone outwards electromagnetic return forces are created such that the magnitude of the return forces is dependent on the strength of the electrical current.

Description

Electromagnetic torsional stiffness element of variable stiffness The invention relates to an electromagnetic torsional stiffness element more variable Rigidity with a magnetic field that acts on a current-carrying conductor Exerts force effects, with pairs of poles in any arrangement through an air gap separated, opposite polarity and in this air gap a movably arranged Conductor is attached, through which an electric current flows in such a direction becomes that when the conductor moves out of the neutral zone, electromagnetic Restoring forces arise, and the amount of the restoring force by varying the Amperage can be influenced and changed.

As is known, mechanical torsional stiffness elements have long been found in a variety of practical designs, especially in torque measurement technology, Use. These designs are with coil springs, torsion bars, combinations constructed of compression and tension springs with a lever arm, etc. acting on the rotary system.

This makes use of the property that every angle of rotation oG is assigned a corresponding torque. If one refers to the torque MD the angular deflection is obtained as the so-called angle reference size D *; D * (α) = dMD d Since the directional angle is generally a function of the angle of rotation, For each angle of rotation the corresponding torque results from MF (α) = # D * (α) dα d D * (α) If = const., then there is a d OC linear torsional stiffness characteristic with the slope D *.

If this differential quotient is a function of α, then results a non-linear torsional stiffness characteristic curve, depending on whether it is progressive or degressive characteristic. These mechanical torsional stiffness elements have however, the following disadvantages.

1. High manufacturing and adjustment costs.

2. Susceptibility to mechanical vibrations.

3. Zero point instabilities, caused by influences in the clamping area the spring elements.

4. Changeover of the torsional stiffness in terms of a measuring range changeover iat only possible with a high design effort and limited accuracy.

5. Change in the torsional stiffness properties when the Torsion spring elements.

The invention is therefore based on this prior art, the task underlying an electromagnetic torsional stiffness element more variable To create rigidity which avoids the disadvantages mentioned above, the Amount of restoring force per deflection angle by varying the current strength can be influenced and changed.

According to the invention, this object is achieved by using magnetic Pairs of poles opposite each other with an air gap arranged in a circular ring and in these Air gap inserts an electrical conductor movably. If you send an electric one Current I through the conductor causes the electromagnetic attacking it Powers, according to the "rule of the left hand". if the current direction is correctly selected, that the conductor adjusts to the "magnetically neutral zone".

Moving the conductor out of this neutral zone is after both Directions only possible with the application of an appropriate force, i.e. the arrangement has in principle the behavior of a mechanical spring, or in other words, exist around the geometrical location of the neutral zone, depending on the deflection, Restoring forces. When the winding is rotatable with respect to the ring magnet or vice versa is arranged, a restoring torque is generated depending on the current strength.

The zero position of the system is given by the position of the neutral zone. This results in a directional angle variable, the amount of which depends on the current I.

The aim is to generate a restoring torque, analogous to a Torsion spring and change in the restoring torque per deflection unit through variation the strength of the current.

The following description will describe an embodiment of the invention explained in more detail with reference to the drawing.

It shows Fig. 1 a sectional view of the complete electromagnetic Torsional stiffness element.

Fig. 2 The arrangement of the winding in the rotatable coil carrier disc Fig. 3 The ring magnet with the magnetic return disc.

Fig. I shows the ring magnets 1 and 2 with the magnetic yoke discs 3 and 4. The parts 1, 2 and 3, 4 are embedded in the housing 5 so that there is an air gap 6 results, in which the conductor 7 moves with the coil carrier disk 8 and on the shaft 9 is mounted centrally to the ring magnets I and 2.

Fig. 2 shows the conductor 7 with the coil carrier disc 8 and the direction of entry of the electric current I.

Fig. 3 shows the ring magnet 2 with the magnetic return disc 3 and the neutral zone 10.

Claims (6)

P a t e n t a n s p r ü c h e 1. Electromagnetic torsional stiffness element of variable stiffness with a magnetic field, which acts of force on a current-carrying conductor exercises, characterized in that at least two pole pairs in any preferably ring-shaped, arranged opposite one another, separated by an air gap, and that a movably arranged conductor is mounted in this air gap, the is traversed by an electric current I in such a direction that bel one Movement of the conductor out of the neutral zone, electromagnetic restoring forces arise, and that the amount of the restoring force depends on the electrical current is dependent. 2. Electromagnetic torsional stiffness element of variable stiffness with a magnetic field, which acts of force on a current-carrying conductor exercises, according to claim I, characterized in that the amount of the restoring force or the restoring torque is increased in that more than two pairs of poles and correspondingly many conductor elements are used. 3. Electromagnetic torsional stiffness element of variable stiffness with a magnetic field, which acts of force on a current-carrying conductor exercises, characterized in that the amount of the restoring force or the restoring torque is increased by the fact that instead of one conductor per pole pair, several conductors, i.e. a number of turns of size I is used. 4. Electromagnetic torsional stiffness element of variable stiffness with a magnetic field, which acts of force on a current-carrying conductor exercises, characterized in that by laying out the location dependence of the magnetic Field strength of the magnetic poles, any dependencies of the restoring forces on the Deflection (linear, progressive, degressive) or restoring torques from the angle of rotation can be generated. 5. Electromagnetic torsional stiffness element of variable stiffness with a magnetic field, which acts of force on a current-carrying conductor exercises, characterized in that, through a suitable design of the coil geometry, any dependencies of the restoring forces or moments generated by the aga steering can be. 6. Electromagnetic torsional stiffness element of variable stiffness with a magnetic field, which acts of force on a current-carrying conductor exercises, characterized in that the for generating a restoring force or Reset torque required coil is isolated in recesses of an electrically conductive antimagnetic material that becomes an integrated System of eddy current damping and spring or torsional stiffness results in ..