DE102004055994B4 - Actuator for fast-switching processes - Google Patents

Abstract

Actuator for fast-switching processes with - a coil system with a coil (4) and - an armature (2), which is arranged to be adjustable by a magnetic field excited by the coil (4), with - a short-circuit sleeve (5), the coil system ( 4) is arranged adjacent, characterized in that the short-circuit sleeve (5) is made of a material for lowering an impedance of the coil system.

Description

The invention relates to an actuator for fast-switching operations with the preamble features of claim 1.

Such an actuator is z. B. off DE 195 04 185 A1 known. Other actuators describe z. B. the US 3,553,618 A . JP 63265407 A and DE 89 14 262 U1 ,

Actuators for fast-switching operations are used, for example, to perform fast strokes, the strokes can also be oscillating. With such an actuator, for example, scanner units can be driven or valve units can be controlled by opening and closing the valve such that their pressure characteristic is modulated.

Known actuators have a conventional structural design with a coil on a winding body, wherein an armature is moved within the winding body by a coil activation by applying an electric current. About the anchor a plunger is moved, wherein the plunger is formed, for example, at the front end as a valve closer for opening and closing a valve.

To achieve a fast switching movement, a control by means of overexcitation takes place in the case of a fast-switching actuator. In this case, a shortening of the switching time is achieved via a defined voltage or current increase in the start-up phase.

Disadvantages of such drives or fast-switching actuators consist in an increased effort in the electronics, overstressing the drives in the starting phase and difficulties to achieve switching times less than 10 ms.

The object of the invention is to propose an alternative structural design for an actuator for fast-switching operations.

This object is achieved by an actuator for fast-switching operations with the features of claim 1.

Particularly preferred is an actuator for fast-switching operations with a coil system with a coil and with an armature which is arranged adjustable by a magnetic field excited by the coil. According to the invention, the actuator is implemented by a short-circuiting sleeve which is arranged adjacent to the coil system, this being made of a material for lowering an impedance of the coil system.

Advantageous embodiments are the subject of dependent claims.

In particular, an actuator is preferred in which such a short sleeve is arranged on the inside, outside or inside and outside of the coil system. Accordingly, a structural design of a fast-switching actuator is preferred, in which one or more shorting sleeves are attached to the inner or outer coil system or to either the inner and the outer coil system.

As a result, the impedance of the coil system is lowered and it can be realized particularly fast current increases, thereby enabling a fast feed movement of the armature. The coil system usually consists of the coil and a bobbin on which the coil is wound. Alternatively, however, the short-circuiting sleeve could already completely or partially replace the winding body.

In particular, an actuator is preferred in which the short-circuit sleeve at least partially covers soft-magnetic parts of the armature.

In particular, an actuator is preferred in which at least parts of the armature are formed from hard magnetic materials. In a corresponding fast-switching actuator, the permeability of the armature or rotor is reduced. This is achieved by the use of hard magnetic materials whose permanent permeability is very low. The then constructed drive is able to work on the hybrid principle and can apply electrodynamic forces and interfacial forces.

In particular, an actuator in which a permeability is reduced, in particular minimized, by a particularly high magnetic flux density in the soft magnetic core, in particular in the armature, is preferred. In such a fast-switching actuator, the permeability is minimized by high magnetic flux density in the soft magnetic core or armature. This also enables a lowering of the coil impedance.

An embodiment will be explained in more detail with reference to the drawing. Show it:

1 a perspective view and a sectional view of a valve with an actuator for the circuit and

2 a diagram of a coil current as a function of time in an actuator according to the prior art or according to 1 ,

Like this 1 it can be seen are in a housing 3 a variety of different components added. In the illustrated embodiment is a valve 0 , whose pestle 1 over an anchor 2 a fast-switching actuator is actuated. However, a corresponding implementation is also advantageous for actuators that operate different types of switching or setting operations.

The housing 3 consists in the illustrated embodiment of a rear actuator housing 30 , on the front side a valve housing or valve body 31 arranged and attached. In the actuator housing 30 is a coil 4 on a bobbin 6 wound. Advantageously, the winding body 6 designed in the form of a reel. Via connection contacts 60 which comes from the actuator housing 30 protrude, is a voltage or current to the coil 4 can be applied to excite a magnetic field. The winding body 6 surrounds a space in which in the longitudinal direction of the bobbin 6 centrally an armature assembly with the plunger 1 leads. The pestle 1 is on a soft magnetic anchor 2 attached and is by a means of the coil 4 generated magnetic field in the direction of the front end adjusted, so that a valve channel by means of a front side of the plunger formed valve closer 32 is closed. To reset the plunger 1 and the anchor 2 When deactivating the magnetic field serves a return spring 7 , which in the front valve body 31 on the one hand and on the other hand on the front end of the anchor 2 is supported.

To reduce the impedance of the coil system and realize faster current increases, thereby rapid feed movement of the armature 2 with the pestle 1 to allow at least one shorting sleeve in the actuator 5 used. In the illustrated embodiment, the shorting sleeve 5 in the range of the inner diameter of the coil system, ie between coil 4 and anchor 2 arranged. According to further advantageous constructive embodiments, such a short-circuiting sleeve 5 also in the area of the outer diameter of the coil system, ie on the outside around the coil 4 extending, or be arranged both on the inner and on the outer diameter. The task of the shorting sleeve 5 consists of the soft magnetic anchor parts of the armature 2 to thereby reduce the impedance of the coil system. As a result, faster current increases in the coil system are possible, resulting in a fast response of the armature 2 on an excited magnetic field requires or allows.

According to a preferred embodiment, the armature system is partially executed with low-permeability material to further improve the switching properties. Niederpermeables material may preferably be hard magnetic material or hard magnetic material, the energy then in the course of a hybrid drive in addition to the electrodynamic power delivery in addition to the effect on interfaces can be exploited. The actuator or actuator constructed in this way then operates on the hybrid principle and can apply electrodynamic forces and interface forces.

Advantageously, in such a fast-switching actuator, the permeability can be reduced, in particular minimized, by a high magnetic flux density in the soft-magnetic core. As a result, a lowering of the coil impedance is also possible.

A dimensioning of the movable anchor part or the anchor 2 in lightweight construction and a conscious high magnetic field load in cross section can also reduce the permeability of the soft magnetic material of the armature 2 be used.

2 shows an example of an increase of the coil current in the coil 4 in the case of an actuator with or without shorting sleeve 5 , Well recognizable is a much faster increase of the current after the activation of the coil 4 with shorting sleeve or after the start of the excitation of a magnetic field through the coil 4 ,

Claims (7)

Actuator for fast-switching operations with - a coil system with a coil ( 4 ) and - an anchor ( 2 ), which by means of the coil ( 4 ) is arranged adjustable magnetic field, wherein - a short-circuiting sleeve ( 5 ), the coil system ( 4 ) is arranged adjacent, characterized in that the shorting sleeve ( 5 ) is made of a material for lowering an impedance of the coil system. Actuator according to Claim 1, which has such a short-circuiting sleeve ( 5 ) is arranged inside, outside or inside and outside of the coil system. Actuator according to any preceding claim, wherein the short-circuiting sleeve ( 5 ) soft magnetic parts of the armature ( 2 ) at least partially covers. Actuator according to any preceding claim, wherein at least parts of the armature ( 2 ) are formed of hard magnetic materials. Actuator according to one of the preceding claims, wherein a permeability by a particular high magnetic flux density in the soft magnetic core, is reduced. Actuator according to claim 5, wherein the core through the armature ( 2 ) is formed. Actuator according to claim 5 or 6, wherein the permeability is minimized.

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