CZ305846B6 - Linear motor - Google Patents

Abstract

The present invention relates to a linear motor having placed in its stator, formed by a magnetically conducting shell (1), two excitation coils (2) on pole extensions (3), wherein the excitation coils (2) are separated by a stator adapter (5). Two anchored pole extensions (8) are fastened on a non-magnetic pull rod (7) wherein a permanent magnet (9) is clamped between these anchored pole extensions (8).

Description

Linear motor

Field of technology

The invention relates to linear motors which control pneumatic or hydraulic controls by electric current and enable them to be connected to superior electronic systems, for example to a machine tool control computer.

Prior art

For pneumatic and hydraulic equipment, the following basic types of motors are used: torgue motor, electrodynamic motor, magnetostrictive motor, proportional magnet, linear motor and piezomotor. Pneumatic or hydraulic elements, such as directly controlled single-stage valves, most often use non-polarized slower proportional magnets and faster polarized linear motors that have a single excitation coil with a permanent magnet on the stator. The disadvantage of both systems is that in order to achieve the required sensitivity, it is necessary to connect a separate position sensor, which significantly increases the production costs of a pneumatic or hydraulic element.

The essence of the invention

This disadvantage is substantially reduced by the linear motor according to the invention. Its essence lies in the fact that the linear motor has in the stator with a magnetically conductive shell two excitation coils on pole pieces separated by a stator pole piece, while anchor pole pieces are mounted on a non-magnetic rod, between which a permanent magnet is placed.

The design according to the invention makes it possible to evaluate the position without connecting a separate position sensor and to achieve a high sensitivity of the linear motor while significantly reducing the production costs for its production.

Explanation of the drawing

In the accompanying drawing, which shows an example of the invention in more detail, FIG. 1 is a section of a linear motor.

Example of an embodiment of the invention

The linear motor (Fig. 1) consists of a stator and an axially movable armature. The stator is formed by a magnetically conductive housing 1, in which two separate excitation coils 2 mounted on pole pieces 3 are placed, which are axially centered by a non-magnetic housing 4. A stator pole piece 5 is placed between the pole pieces 3. Sliding bushes are pressed in the pole pieces 3. 6, which guide the non-magnetic rod 7. Two steel anchor pole pieces 8 are mounted on the non-magnetic rod 7, between which an axially magnetized permanent magnet 9 is clamped. Axially movable armature, which is formed by a non-magnetic rod 7, steel anchor pole pieces 8 and a permanent magnet 9, is centered by two springs 10 by means of adjustable supports 11.

The permanent magnet 9 magnetizes the working gaps 12 in the corresponding direction and the excitation coils 2 magnetize the working gaps 12 in the opposite direction. The movable armature formed by the non-magnetic rod 7, the steel anchor pole pieces 8 and the permanent magnet 9 is deflected depending on

- 1 CZ 305846 B6 the magnitude and meaning of the electric current. The linear motor according to the invention uses excitation coils 2 and an axially movable armature for the function of both the motor and the position sensor.

Claims (12)

Linear motor, characterized in that in the stator with a magnetically conductive housing (1) two excitation coils (2) are arranged on the pole pieces (3) separated by a stator pole piece (5) and are mounted on a non-magnetic rod (7). two anchor pole pieces (8), between which a permanent magnet (9) is placed. 1 drawing List of reference marks: 1 - magnetically conductive sheath 2 - excitation coil 3 - pole extension 4 - non-magnetic housing 5 - stator pole piece 6 - sliding sleeve 7 - non-magnetic rod 8 - anchor pole extension 9 - permanent magnet 10 -spring 11 - adjustable backrest 12 - work gap.