RU2380810C1 - Submersible motor - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: proposed motor comprises stator (1) housing rotor packs (5) fitted on shaft (4). Moving bearing bushes (6) are arranged on both sides of packs (5). Note here that the rotor incorporates additionally the rings arranged on both sides of said moving bushes to change their radial size at axial loads. Note also that a part of end faces of aforesaid packs, rings and bushes, is made tapered for them to abut, while inner surface of at least of a part of rings, features cylindrical shape. Particularly, taper-inner-surface rings (7) are fitted between every pack (5) and moving bush (6) to adjoin mating surfaces of adjacent packs (5) and bushes (6). Outer rings (12) are arranged on rotor ends, end face surface of said ends being tapered on one side and cylindrical on the other to ensure required axial sizes. Rings (7) and (12) made with cutouts allow adjustment of their radial size under axial load.

EFFECT: longer life, reduced vibration, reduced operating clearances adding to ease of assembly.

6 cl, 6 dwg

Description

The invention relates to the field of mechanical engineering, in particular to submersible motors for lifting formation fluid.

A design feature of submersible motors is a relatively small diameter and a large length. The rotor of such an electric motor must have intermediate bearings, the housing of which is installed in the stator bore, and the bushings and packages, the number of which reaches twenty, on the shaft. When assembling the electric motor, the packages and bushings of the bearings must be dragged through the entire length of the shaft, which in powerful motors reaches 9 meters. This requires sufficiently large technological gaps. When the rotor rotates, the packages are shifted by the size of the technological gap, which leads to vibration of the engine and increased wear of the bearings, especially in electric motors with an increased speed.

Known submersible electric motors containing a stator with phase windings, bearings and a rotor. The rotor includes a shaft, packages and a moving part (bushings) of bearings (RF patent for utility model No. 65314, Н02К 29/00, published on July 27, 2007).

The disadvantage of this design is the need for capacity building to produce a multi-section electric motor, which greatly complicates its design.

The closest in technical essence to the claimed one is a submersible motor containing a stator, bearings and a rotor, a fixed part (housing) of the bearings is installed on the inner surface of the stator, the rotor includes a shaft, packages and a moving part (bushings) of the bearings, while the bearing bushings are placed on both sides of each package (A. Bogdanov, Submersible electric pumps for oil production. M: Nedra, 1968, p. 131, p. 153).

The known electric motor has a low service life, especially at increased speeds, due to vibration due to the presence of technological gaps between the shaft and the bushings, as well as between the shaft and the packages.

An object of the present invention is to increase the service life of a submersible motor by reducing vibration. Vibration reduction is achieved by eliminating technological gaps.

The specified technical result is achieved by the fact that in the submersible motor for submersible electric pumps containing a stator and placed inside its rotor in the form of packages mounted on a shaft and alternating with movable bearings of the bearings, the housing of which is fixed to the inner surface of the stator, according to the invention, the rotor is additionally equipped with rings, placed on both sides of the movable bushings and having the ability to change the radial size under axial load, while at least part of the end faces The dimensions of the packages, rings and bushings facing each other are conical with the possibility of their abutment, and the inner surface of at least part of the rings has a cylindrical shape.

The most technologically advanced in the manufacture of rings made with one through slot, parallel to the axis of the shaft. To reduce the likelihood of jamming rings, rings with longitudinal slots open on one side and parallel to the shaft axis can be used. The angle of inclination of the chord with a curved generatrix of the conical end surfaces or the generatrix of the cones to the axis of the shaft is within 10-65 degrees. To fix the assembly in the axial direction at the ends of the rotor shaft, it is advisable to install stops that can contact external rings having a conical surface, and in the case of using external rings with a flat end surface facing the stop, a spring is placed between the stop and the flat end of the ring.

The installation in the electric motor of additional rings with the claimed profile and the matching of the shape of the contacting surfaces of the packages and bushings make it possible to eliminate technological clearances between the bearing bushings and the shaft, as well as between the shaft and the package, necessary for the assembly of the electric motor, while maintaining the manufacturability of the assembly. The inventive design reduces the unbalance of the rotor due to the absence of gaps, and due to the possibility of balancing each package. This reduces the level of vibration of the device, the wear of bearings, and therefore, increases the service life of the electric motor.

The invention is illustrated by drawings, where figure 1 presents a fragment of the active part of a submersible electric motor; figure 2 - node separate bearing with rings and emphasis; figure 3 is a ring with two conical end surfaces and one through slot, a General view; figure 4 - ring with two conical end surfaces and several longitudinal slots open on one side; figure 5 is a scan of the outer surface of the ring of figure 4; figure 6 is a ring with one conical and one flat end surfaces.

The submersible electric motor contains a stator 1, in the housing of which a laminated magnetic circuit 2 is pressed from sheets of electrical steel. Cases 3 bearings are connected with its inner surface. Packages 5 are mounted on the rotor shaft 4, on both sides of which movable bushings 6 of the bearings are placed. Between each packet 5 and the movable sleeve 6, rings 7 are inserted. The end surfaces of the rings 7 are conical and tightly adjacent to the mating surfaces of adjacent packages 5 and the movable bushings 6 (Fig. 1). External rings 12 (FIGS. 2, 6) adjoin the outer end surface of the bushings 6 at the ends of the rotor, which are supported by stops formed, for example, by a cylindrical bush 9 and half rings 8 buried in grooves on the shaft 4 (FIGS. 1, 2) . The stops rigidly fix the rotor on the shaft 4 and prevent its axial displacement. In the upper part of the electric motor, the emphasis is additionally equipped with a nut 10 (Fig. 2), connected to regulate the axial force with the sleeve 9 through a threaded connection. Between the outer ring 12 and the emphasis is placed a spring 11, which serves to create axial force. The end surface of the outer rings 12 can be made conical on one side and cylindrical on the other (FIGS. 2, 6), which ensures a reduction in axial dimensions. In addition, the role of the stops can be performed by structural elements mounted on the shaft, in particular the impeller of the pump, which serves to circulate the oil inside the electric motor. Rings 7 and 12 can be made with a through slot 13 (FIG. 3) or with slots 14 parallel to the shaft axis, with a length not exceeding half the ring width. In the latter case, the slots 14 can be staggered with an open end on opposite end faces of the ring (Figs. 4, 5).

In the claimed design, each package of the rotor creates an axial force during assembly, which is transmitted through the conical surface to the ring, which leads to its deformation. The inner surface of the ring is pressed against the shaft, packages and movable bushings of bearings are mounted on the shaft without gaps. The packages cannot move in the radial direction, the rotor unbalance is reduced, the vibration in such an electric motor is sharply reduced, and the service life is increased.

Claims (6)

1. Submersible motor for submersible electric pumps, containing a stator and placed inside its rotor in the form of packages mounted on a shaft and alternating with movable bushes of bearings, supported by an external bush on the inner surface of the stator, characterized in that the rotor is additionally equipped with rings placed on both sides of the movable bushings and having the ability to change the radial size under axial load, while at least part of the end surfaces of the packages, rings and bushings facing each other a friend, made conical with the possibility of their abutment, and the inner surface of at least part of the rings has a cylindrical shape. 2. The submersible motor according to claim 1, characterized in that the rings are made with a through slot parallel to the axis of the shaft. 3. The submersible motor according to claim 1, characterized in that the rings are made with slots that are parallel to the axis of the shaft and open from one of the ends. 4. The submersible motor according to claim 1, characterized in that the angle of inclination of the chord of the generatrix of the cone-shaped surfaces to the axis of the shaft or generatrix of the cones is in the range of 10-65 °. 5. Submersible motor according to claim 1, characterized in that at the ends of the rotor shaft there are stops for axial locking in contact with the outer rings. 6. Submersible motor according to claim 1, characterized in that a spring is placed between the stop and the outer ring.

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