CS243299B1 - Labour-saving bar of brush holders - Google Patents

Abstract

Energy-saving rotating brush holder bar electric machine consists of steel or cast iron bars (1) finished with roughened cylindrical or conical pin. The bar has longitudinal knurling (4) and holes on one surface (5) for fixing screws. Roughened of the pin (2) is by lining or sealing the insulating sleeve (6) fastened closed bottom (7) and with collar (8) as an insulator.

Description

(54) Energy-saving brush holder bar

The economical brush holder of the rotary electric machine consists of a steel or cast iron bar (1) terminated by a roughened cylindrical or conical pin. The strip has longitudinal grooves (4) and holes (5) for fastening screws on one surface. An insulating sleeve (6) enclosed by a bottom (7) and provided with a collar (8) in the form of an insulator is fastened to the roughened pin (2) by pressing or cementing.

BACKGROUND OF THE INVENTION The present invention relates to an energy-saving bar for attaching brush holders to a collecting device of a rotating electrical machine.

Up to now, the economical strips for fastening the brush grooves have been carried out according to the invention AO 205 926 in such a way that the steel mandrel of the insulating plug is embedded in the steel grooved strip. The disadvantage of this solution is the necessity of precise machining of the steel mandrel of the insulating gag and a calibrated hole in the steel grooved rail, not only in terms of dimensions and surface roughness, but also in geometric position. In addition, the economical rails are made by winding fiberglass insulation onto the roughened cylindrical end of the steel rail. After insulation, this insulation is machined into a cylindrical shape and a narrow insulating disc is adhered directly to the steel rail to increase the surface insulation distance. The disadvantage of this solution is the manual and unhygienic production of fiberglass insulation.

These disadvantages are avoided with the economical rail of the present invention. The essence of the invention is that an insulating sleeve closed by a bottom and provided with a collar in the manner of an insulator is fastened to the roughened stud of the energy-saving bar.

..Every bar is usually steel. However, sometimes it may be advantageous to cast a low-cost gray cast iron bar, as the casting allows the necessary shaping and recessing of the mounting parts of the brush holders without complicated machining.

Since the insulating sleeves can be manufactured inexpensively by molding from the insulating material, machining is limited to simple machining of the cylindrical functional surface of the insulating sleeve. This treatment eliminates the inevitable technological conicity which serves to facilitate removal of the insulating sleeve from the mold.

An exemplary embodiment of the invention is illustrated in the accompanying drawing, in which Fig. 1 is a partial cross-sectional front elevation view, Fig. 2 is a cross-sectional view in the plane A-A and Fig. 3 is a cross-sectional view in the plane B-B.

The steel strip 1 of rectangular cross-section is terminated at one end by a pin 2 which

Claims (1)

Subject 1. An economical brush holder bar of a rotating electric machine comprising a knurled bar terminated by a roughened pin, characterized in that it is roughened on the roughened pin (2) by crimping 3. The pin 2 can be cylindrical or conical. Grooves 4 are provided on one wider surface of the bar 1 and holes 5 are provided for adjusting and fastening the brush holders. An insulating sleeve 6 is fastened to the pin 2 of the bar 1, which is closed by a bottom 7 and is provided with an insulating-like collar 8. The insulating sleeve 6 can be fixed to the roughened pin 2 by molding in the mold, or the separately manufactured insulating sleeve 6 can be glued or cemented to the roughened pin 2, respectively. After manufacture, the energy-saving bar is clamped into a prismatic jig, the two centering planes of which are grooved and one narrower surface of the steel bar 1. The jig thereby ensures parallelism of the axis of the cylindrical functional surface 9 of the insulating sleeve 6 and its prescribed distance from the grooved surface. The machining of the cylindrical functional surface 9 is illustrated by a conventional V-shaped mark. Since the separately pressed insulating sleeve 6 must have a conical cavity for technological reasons, it is advantageous to provide a roughened pin 2 with the same conicity. Before sealing, gluing or embedding, the insulating sleeve is mounted on the roughened pin and rotated back and forth several times. The studs of the roughened pin will scratch the smooth natural surface of the cavity of the insulating sleeve, thereby roughening it, which will increase the strength of the sealed or potted joint. Of course, the rough natural surface of the insulating sleeve cavity can be roughened as a separate machine operation. It is also advantageous to mold longitudinal grooves or grooves in the cavity of the insulating sleeve, which together with the roughened surface of the pin forms a lock to increase the load-bearing capacity of the cemented or potted joint. The longitudinal grooves or grooves in the cavity of the insulating sleeve do not prevent it from being removed from the mold. The insulating sleeve can be made of any insulating material with the necessary properties. For example, a material used for molded commutators or a sintered material containing glass and mica are suitable.