SU930503A1 - Electric machine - Google Patents

Description

(5) ELECTRIC MACHINE

one

The invention relates to electrical engineering, in particular to closed blown electrical machines.

A known closed blown electrical machine in which the ventilation hood mesh has square holes.

The dimensions of the side of a square in such a grid cannot be made larger than a certain value, corresponding to the degree of protection of the electric machine to.

However, limiting the size of the holes leads to an increase in the aerodynamic drag at the entrance to the fan.

An electric machine is also known, comprising an external blower fan, enclosed by a casing with internal and external parallel grids, the jumpers of one of which form square holes.

However, since the grids in this design are located close to each other, the dimensions of the side of the square formed when the grids are applied, as in the first case, limited values can be made, which increases the aerodynamic resistance, reduces gas consumption and increases the temperature of the active parts of the electric cars.

ten

The purpose of the invention is to reduce aerodynamic drag while ensuring safety conditions.

This goal is achieved by

15 that in a known electric machine comprising an external blower fan, enclosed by a casing with an internal and parallel-arranged external grids, the jumpers of one of

Claims (2)

20 of which form square holes, the other grid is made with similar square holes, the grids are located at 3, 93 distances no greater than the length of the jumpers, and the holes of one grid are symmetrically shifted relative to the holes of the other grid. FIG. G shows an electric machine; longitudinal section; figure 2 is a view of the grid from the end of the electric machine; in fig. 3 and 4 are versions of the fan casing. The electric machine contains a ventilator for an external blower mounted on / out of the shaft 2 from the housing 3 and closed with a casing k with two mutually overlapping parallel grids, the outer 5 and the inner 6, the jumpers 7 and 8 of which form identical square holes 9, symmetrically offset from each other so that the center O of the hole of the grid approximately coincides with the center 0 of the intersection of the jumpers of the other grid and vice versa, while normalized holes 10 of the grid 5 are formed in the light and b are placed in the casing at a distance from one another no more than the size of jumpers forming normal ventilation holes. Such a design allows a significant increase in the living cross section and, accordingly, a decrease in the aerodynamic resistance, while maintaining the necessary degree of protection. Claims of the Invention An electrical machine comprising an external blower fan, enclosed by a casing with internal and external parallel grids, the jumpers of one of which form square arrays, wherein in order to reduce aerodynamic resistance while ensuring safety conditions, the other grid is made similar square holes, the grids are located one from another at a distance no greater than the length of the bridges, and the holes of one grid are symmetrically shifted holes in another mesh. Sources of information taken into account in the examination 1.L.E. Alekseev. Electrical machine designs. L.-M., Gosenergoizdat,, p. 52, fig. 2-31. 2. Catalog 125-10. Oz Aca Safety e Motors and AKG Flameproof Motors, 1977. Fi.2 P "g, 5 FIG. four