SU896721A1 - Electric motor with screw-shaped stator - Google Patents

Description

one

The invention relates to electrical engineering and can be used in drives that require the displacement of a movable element in the axial direction with its rotation around the longitudinal axis of the engine if it is necessary to achieve a smooth control of the speed of the screw movement in a wide range and the need to obtain an exact stop of the working member. One of the important fields of application of the invention is the electric drive of industrial robots and manipulators, where a combination of translational and rotational movements and the achievement of accurate positioning is required.

Known asynchronous and reactive stepping motors, giving the opportunity to get a screw movement of the moving element due to the special design of the stator and the rotor of the engine.

In such engines, the stator carrying a multiphase winding has the shape of a cylinder, on the inner surface of which a two-way screw thread is cut. The rotor of the engine is made in the form of a cylinder of ferromagnetic material - with ring cutting, the pitch of which is equal to the tag of the screw thread of the stator.

The multi-phase winding, laid in the slots of the stator, creates a rotating field in the machine. In this case, the poles forming a dies on the stator, due to the screw thread on its inner surface, move in the axial direction. The rotor moves synchronously with the movement of the stator poles by the magnitude of the double screw pitch per rotation of the rotating field, providing precise linear movement 1.

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Also known is an electric motor with a helical stator, in the slots of which the working winding is laid, and a rotor. This engine also provides screw motion.

20 rotor 2.

A disadvantage of the prior art engine is the impossibility of achieving significant ranges of variable speed control.

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The purpose of the invention is to expand the range of speed control.

Claims (2)

The goal set is achieved by the fact that an additional groove is made in the magnetic core, in which 30 is laid on the field winding, and the placement slots are the working winding located on the adjacent coils, which have common longitudinal axes, and the length of the working winding is a multiple of 2 B, the length of the section of the winding of the exciter 5KDeni is equal to (2K + 1) yy, where, 1,2, 3, ..., and on the rotor there are screw-shaped protrusions of a length equal to tx, located at a distance of t Figure 1 shows the stator magnetic circuit with grooves for laying the working winding and the field winding, in Fig. 2 - ro the torus with formiruni magnetic field with screw-shaped protrusions in FIG. 3 is a schematic scan of the stator and the rotor of the engine / in FIG. 4 — an engine with two screw-shaped stator magnetic cores. The electric motor contains a screw-shaped magnetic core of the stator 1, In the grooves ot of the magnetic core, an operating winding 2 is placed, and the slots a have common longitudinal axes. An additional groove b is made in the center of the stator magnetic circuit, in which the excitation winding 3 is laid. The length of the section of the magnetic circuit on which the excitation winding 3 is located is equal to " 2K + 1) gG, where, 1, 2, 3 ,. . . , polarization of the motor, and the length of the sections for the working winding is a multiple. The working windings are made in accordance with the working windings of linear DC motors and connected either to the collector plates of the electromechanical collector or to the corresponding channels of the semiconductor switch (not shown). The grooves of the working windings in the known device of the stator magnetic core are located exactly against each other, in the proposed engine the common winding for both parts of the magnetic core is used, the working winding, which allows, depending on the thread pitch, 1.5–3.5 times to reduce the amount of frontal parts of the working winding and, accordingly, reduce the weight of the working winding compared to using separate working windings by 25-30%. The ferromagnetic rotor 4 has screw-shaped protrusions 5 of a length equal to tr, and located at a distance C The engine may have two screw-shaped stator magnet cores (Fig. 4). The total length of each stator magnetic conductor in this case does not exceed the length of one thread of the screw line. On each of the stator magnetic cores there is an excitation winding located in a large groove, on the side of which the working windings are located. The slots for positioning the working winding of the respective sections of the magnetic conductors have common longitudinal axes, which makes it possible to carry out the working windings of both stator magnetic cores from the common sections. The engine works as follows. If the rotor occupies, being in the bore of the stator, such a position, for example, in which its protrusions of length T are at opposite ends of the section of the magnetic circuit | a stator with a working winding, and an electromechanical or semiconductor I switch connected it to the mains supply, ensuring the flow of currents in Sp. over the protrusions of the rotor (Fig. 3, dl), while the excitation winding creates a flux F ,. then, in accordance with the law of Bio-Savart-Laplace, an electromagnetic force arises, shifting both protrusions of the rotor to the left. When the screw movement of the rotor started under the action of this force, the collector commutes, sections of the working winding so that the direction of the electromagnetic force is maintained all the time. Motor speed control is carried out as in conventional DC machines by changing the value of the supply mains voltage, or by changing the excitation current, or by inserting additional active resistance in the working winding circuit. In order to reverse the motor, it is necessary to change the polarity of the supply of the working winding or field winding. The invention The electric motor with a screw-shaped stator, in the slots of which the working winding is laid, and a rotor is characterized in that, in order to expand the range of speed control, in the magnetic circuit, an additional groove is made, in which the excitation winding is laid, and the slots for accommodating the working winding are located on adjacent coils, have common longitudinal axes, the length of the section of the working winding is a multiple of 2ZJ, the length of the section of the excitation winding is equal to (2К + 1РгГ, where, 1,2,3, ..., and on the rotor there are screw-shaped protrusions and C, located at a distance. Sources of information taken into account in the examination 1.Paul RJA ,, Reid GG, Stepping-mocle llorf. Zim. Electron. Machines, London, 1974, 77-82. 2. USSR author's certificate number 64142, cl. H 02 K 17/02, 1940. 2G