JPS6120856Y2 - - Google Patents

Description

[Detailed description of the invention] The invention provides a groove-like rib consisting of a plurality of radial grooves extending in the outer diameter direction and an annular groove connecting the grooves around the bearing part on the end face of the outer frame of the electric motor. The purpose of this is to prevent corrosion of the outer frame due to rainwater, and to prevent damage to the bearing due to dew condensation on the inner surface of the outer frame.

Conventional fan motors for cooling condensers used outdoors in air conditioners are often of the rigid type, but in such motors, rainwater falls on the motor and cools the outer frame, causing the inside of the motor to cool. Due to the difference in heat generation temperature, dew droplets were occurring on the inner surface of the motor. Therefore, as shown in FIG. 1, if no measures are taken for the outer frame consisting of the upper frame 1 and the lower frame 2, the dew drops 3 will follow the path shown by arrow A and enter the bearing portion 4. This caused a bearing failure.

In order to prevent this problem, as shown in FIG. A drain hole 6 is provided on the outer periphery of the concave portion 5 of 2.
It is conceivable to provide a However, this structure has the disadvantage that the upper frame 1 may corrode because rainwater accumulates in the recess 5 provided in the upper frame 1 and is not drained. Note that if the recess 5 is not provided in the upper frame 1, the above-mentioned drawbacks will not occur, but in this case, the outer shapes of the upper frame 1 and the lower frame 2 will be significantly different, and a dedicated press mold for each will be required. required, and the cost is high. In Figures 1 and 2, 7 is the rotor shaft;
8 is a stator, and 9 is a rotor.

The present invention has been made in order to eliminate the above-mentioned drawbacks. An embodiment of the present invention is shown below in Figure 3~
This will be explained based on FIG. In FIGS. 3 to 5, the same numbers as above indicate the same members, and 10, 11
are grooves consisting of a plurality of radial grooves facing in the outer diameter direction provided on the axial end surfaces of the upper frame 1 and the lower frame 2, respectively, and an annular groove connecting these grooves around the bearing parts 4, 4. These groove-like ribs 10 and 11 function as a drain for moisture on the outside of the upper frame 1, and as a bank for preventing moisture from entering the bearing portion 4 on the inside of the lower frame 2. . Further, a drain hole 13 is provided in the outwardly protruding portion 12 between the groove-like ribs 11 of the lower frame 2.

With the above structure, dew water generated inside the motor follows a path as shown by arrow B in FIG. 3 and is drained from the drain hole 13. Also,
Water 14 accumulated on the upper end surface of the upper frame 1 is drained out through the groove-like ribs 10 as shown by arrow C.

Although the present invention has the above-described structure and function, the upper frame 1 and the lower frame 2 are made of press-formed iron plates, so that the grooved ribs 10,
11 can be easily formed.

As is clear from the above description, the present invention has a plurality of radial grooves facing in the outer radial direction on the axial side end surfaces of the upper frame and the lower frame made of press-formed iron plates, and each groove is arranged around the bearing part. The radial grooves are provided with grooved ribs consisting of annular grooves connected to each other, and drainage holes are provided in the outward protrusion between the grooved ribs formed on the lower frame. The annular groove functions as a bank to prevent moisture from entering the bearing on the inner surface of the lower frame, simplifying the structure and preventing corrosion from rainwater on the outer frame and damage to the bearing from dew droplets on the inner surface. can be prevented. Further, the upper frame and the lower frame have the same external shape and can be manufactured at low cost using the same press mold.

[Brief explanation of the drawing]

Figures 1 and 2 are half-sectional views of a conventional electric motor.
FIG. 3 is a half-cut sectional view of an electric motor according to an embodiment of the present invention, FIG. 4 is a half-cut sectional view of one outer frame of the motor, and FIG. 5 is a side view of the outer frame. 1... Upper frame, 2... Lower frame, 4... Bearing part, 1
0, 11... Grooved rib, 12... Outward protrusion, 1
3... Drain hole.

Claims (1)

[Scope of utility model registration request] The axial end surfaces of the upper frame and lower frame of the same shape made of press-formed iron plates have a plurality of radial grooves extending in the outer diameter direction, and an annular groove connecting the radial grooves around the bearing. An outer frame for an electric motor, which is provided with groove-like ribs, and a drain hole is provided in an outward protrusion between the groove-like ribs formed on the lower frame.