RU2246165C1 - Electrical machine brush assembly - Google Patents

Abstract

FIELD: electrical engineering; current collecting assemblies of commutator motors.

SUBSTANCE: proposed brush assembly has cylindrical conducting sleeve with protruding cylindrical part and through hole; ring-shaped brush holder is built integral with thin-sheet insulating flange provided with hole; height of protruding cylindrical part of sleeve is not smaller than flange thickness, its diameter is smaller than that of sleeve and equals diameter of sleeve hole; protruding part of sleeve is coaxially inserted in flange hole so that sleeve occurs on flange end opposing location of lugs of brush pigtails.

EFFECT: enhanced reliability of current collection contact.

1 cl, 3 dwg

Description

The invention relates to electrical engineering and is intended for use in the collector nodes of collector motors.

A known design of an electric machine, comprising a housing and a brush assembly including a brush holder, a brush, a coil spring placed at one end in a screw groove, has a groove in the housing in which a brush holder is mounted that is mounted in the housing by the specified screw, and between the brush holder and the screw head an elastic element is located (RF patent No. 2039407, H 02 K 5/14, publ. 09.07.95).

A disadvantage of the known design is the small cross section of the elastic element, which limits the current passing through it.

A known construction of a brush assembly of an electric machine comprising a brush holder body, a brush, a compression spring, a brush holder clip housed in the housing, and a brush lifting device with a spring and a latch that is movable relative to the housing (USSR copyright certificate No. 826472, H 01 R 39 / 42, publ. 30.04.81).

A disadvantage of the known design is the low manufacturability of the device, the complexity of the design and high weight, since the body is made in one piece.

Closest to the alleged invention is the design of the brush assembly of an electric machine, including a brush holder made in the form of a holder equipped with a shelf, brushes with output wires ending with tips, a spring and an attachment element (see Design of DC electric machines. I.N. Rabinovich and I.G.Shubov, “Energy”, Leningrad Branch, 1967, p. 413, Fig. 27-4).

The disadvantages of the known design are the low manufacturability, namely, the execution of the brush holder by a composite, casting method followed by machining to obtain the necessary accuracy and surface cleanliness, in the form of a holder and a shelf mechanically bonded to each other, as well as a decrease in contact reliability due to the composite brush holder.

The task of the invention is to ensure the reliability of the contact at the current collector of the brush assembly and to increase the manufacturability of the manufacture of the brush assembly of an electric machine.

The technical result is achieved by introducing into the brush assembly an electrically conductive sleeve and making a brush holder of a thin-sheet electrically conductive material by stamping and bending.

The problem is achieved in that in the brush assembly of an electric machine containing a brush holder with a holder and a shelf, a brush with lead wires ending with a tip, a spring and a fastening element, according to the invention, an electrically conductive cylindrical sleeve with a protruding cylindrical part and a through hole is inserted, the brush holder is made in in the form of a holder at the same time with a shelf of thin-sheet electrically conductive material by stamping and bending, and a through hole is made in the shelf, the height of the protruding the cylindrical part of the sleeve is not less than the thickness of the shelf, and its diameter is less than the diameter of the sleeve and equal to the diameter of the hole of the shelf, the protruding part of the sleeve is placed in the hole of the shelf, coaxial to it, so that the sleeve is located on the side of the shelf opposite to the location of the tip of the lead wires of the brush, except Moreover, the through hole of the sleeve is made stepped: a larger diameter in the protruding cylindrical part of the sleeve, and a threaded hole of a smaller diameter in the sleeve, which is mechanically connected to the tip m output wires of the brush and the shelf with the help of an attachment element.

The technical result is achieved by performing clips together with the shelf by stamping and bending from thin-sheet electrically conductive material and introducing an electrically conductive sleeve into the brush assembly.

The invention is illustrated by drawings, in which Fig. 1 shows a brush assembly of an electric machine, in section, on a 2: 1 scale; on figa - a cylindrical sleeve, on figb - part of the shelf with a sleeve flared in its hole, in the context, in a scale of 4: 1.

The brush holder contains a holder 1, made at the same time with a shelf 2 of thin-sheet electrically conductive material by stamping and bending, in which a hole 3 is made, a brush 4 with lead wires 5 provided with a tip 6, a cylindrical sleeve 7 with a protruding cylindrical part 8, the diameter of which is smaller than the diameter of the sleeve 7 (FIG. 1). A stepped through hole 9 is made in the sleeve 7, where 9a is the hole in the protruding cylindrical part 8, and 9b is the hole in the sleeve 7, which is threaded, and its diameter is smaller than the diameter of the hole 9a in the protruding part 8 of the sleeve 7 (Fig. 2a). The brush holder also contains a screw 10 for mechanical fastening of the tip 6 of the lead wires 5, located in the hole 9 of the sleeve, a spring 11 that secures the brush 4 in the holder 1 of the brush holder, as well as the washer 12 and the protective washer 13 for attaching the screw 10 (figure 1) .

The diameter of the protruding part 8 of the sleeve 7 is equal to the diameter of the hole 3 in the shelf 2, therefore, the protruding part 8 of the sleeve 7 is located in the hole 3. The sleeve 7 is located, for example, on the lower side of the shelf 2, and the tip 6 of the lead wires 5 of the brush 4 is located on the upper side of the shelf 2, that is, from the side of the shelf opposite to the location of the tip 6 of the lead wires 5 of the brush 4 (Fig. 1), while the protruding part 8 of the sleeve 7 is expanded in place (Fig. 2b).

Consider the assembly sequence of the brush assembly.

The sleeve 7 is placed by the protruding cylindrical part 8 in the hole 3 of the shelf 2, for example from the lower side of the shelf 2, this is possible, since the internal diameter of the hole 3 of the shelf 2 coincides with the external diameter of the protruding part 8 of the sleeve 7, and is expanded in place (Fig.2b) . The brush 4 is placed in a holder 1 and fixed with a spring 11. On the upper side of the shelf 2, a tip 6 of the lead wires 5 of the brush 4 is placed, then a protective washer 13 and a washer 12, and then a fastener, for example a screw 10, placed in a through threaded hole 9 of the sleeve 7, and mechanically fasten the shelf 2, the tip 6 and the sleeve 7 with a screw 10 (Fig. 1, 2a and 2b).

The presence in the claimed design of the brush assembly of the electrical machine of the electrically conductive sleeve 7 having the required length of the threaded hole provides the necessary compression of the tip 6 of the lead wires 5 of the brush 4 to the shelf 2 of the holder 1 of the brush holder to create reliable electrical contact between them.

The design advantages of the inventive brush assembly of an electric machine are:

- improving the manufacturability of the manufacture of the holder of the brush holder of an electric machine;

- ensuring the reliability of contact at the point of current collection of the brush assembly between the tip of the output wires of the brush and the shelf of the holder of the brush holder.

This is achieved by performing a clip by stamping and bending of thin-sheet electrically conductive material at the same time with the shelf and by introducing into the brush assembly an electrically conductive sleeve with a thread length necessary for reliable mechanical connection of the tip of the lead wires of the brush and the holder of the brush holder.

Claims (1)

A brush assembly of an electric machine comprising a brush holder with a clip and a shelf, a brush with lead wires ending with a tip, a spring and a fastening element, characterized in that it is equipped with an electrically conductive cylindrical sleeve with a protruding cylindrical part and a through hole, while the brush holder is made in the form of a clip at the same time with a shelf of thin-sheet electrically conductive material by stamping and bending, and a hole is made in the shelf, and the height of the protruding cylindrical part of the sleeve is not less than t the flange of the shelf, and its diameter is smaller than the diameter of the sleeve and equal to the diameter of the hole of the shelf, the protruding part of the sleeve is placed in the hole of the shelf, coaxial to it, so that the sleeve is located on the side of the shelf opposite to the location of the tip of the lead wires of the brush, in addition, the through hole of the sleeve made stepped: a larger diameter in the protruding cylindrical part of the sleeve, and a threaded hole of a smaller diameter in the sleeve, which is mechanically connected to the tip of the output wires of the brush and the shelf with schyu fastening element.

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