JPH04236147A - Cooling unit for motor - Google Patents

Abstract

PURPOSE:To partition the interior of a cooler cover through partitions into a plurality of inner air paths along a cooling element and to realize effective contact of hot air with the cooling element in each inner air path. CONSTITUTION:A plurality of inner air paths 1c, 1d are provided between cooling elements 1 or between the cooling element 1 and a cooler cover 3 while being partitioned by means of partitions 2A, 2B so that hot air flow from a motor 11 is not impeded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor cooling device that is attached to a totally enclosed external fan type motor or the like and efficiently cools the inside air inside a bracket.

0002

2. Description of the Related Art FIG. 5 is a sectional view showing a conventional cooling device for an electric motor. A partition plate that closes the space between each cooler element 1 as shown in FIG.
3 is a cooler cover that houses the cooler element 1, 1a
is an internal air ventilation path between each cooler element 1, and both end faces are closed by the partition plate 2 as described above. 1b is an outside air ventilation path created inside the cylinder of the cooler element 1. Further, FIG. 7 is a cross-sectional view showing a state in which the air cooler and the electric motor M are combined as an example, and the electric motor M is equipped with a stator 12, a rotor 13, an internal circulating air fan 14, etc. Forms a well-known structure. Further, 15 is an external circulating air fan attached to the end of the rotor shaft 16;
5 is a cooler inlet provided by opening a part of the bracket 11, 5 is a cooler outlet, arrow a is a flow of inside air, and arrow b is a flow of outside air.

Next, the operation will be explained. First, hot air generated inside the electric motor M circulates inside the electric motor M as shown by arrow a, enters the internal air ventilation path 1a between the cooler elements 1 from the cooler inlet 4, and collides with the partition plate 2. It exchanges heat with the outside air flowing in the axial direction through the outside air ventilation path 1b, and enters the inside of the electric motor M from the cooler outlet 5. In this case,
When the inside air inside the electric motor M passes through the inside of the cooler, most of this inside air flows perpendicularly to the cooler element 1, as shown in FIG. 7, so a vortex is generated on the back side of the partition plate 2. In addition, a stagnation phenomenon is observed in some parts, and as a result, although the local flow velocity is high, the average heat transfer coefficient as a cooler is low considering the effective cross-sectional area of the cooler element 1.

0004

[Problems to be Solved by the Invention] Since the conventional electric motor cooling device is constructed as described above, sufficient cooling efficiency of the cooler element 1 cannot be obtained by using outside air, which eventually leads to overheating of the electric motor M. , there were problems such as burnout of the magnetic circuit, etc.

[0005] This invention was made to solve the above-mentioned problems, and the inside air flowing inside the cooler cover is separated by partition plates that follow the streamlines of the inside air flowing from the cooler inlet to the cooler outlet. By flowing through a different route,
It is an object of the present invention to provide a cooling device for an electric motor that eliminates the generation of vortices in each route and increases the flow velocity perpendicular to each cooler element, thereby enabling efficient heat exchange with outside air.

[0006]

[Means for Solving the Problems] A cooling device for an electric motor according to the present invention allows the flow of hot air sent from the electric motor through the cooler inlet into the gap between the cooler elements and between the cooling element and the cooler cover. A plurality of internal air ventilation channels are provided to smoothly separate the flow of air without causing any obstruction.

[0007]

[Operation] Hot air in the electric motor in this invention flows in from the cooler inlet and is divided into a plurality of internal air ventilation paths in the cooler cover, and among these, the inner flow crosses the central partition plate and exits the cooler. The flow towards and outside the cooler element flows orthogonally over the top of the cooler element and moves axially over the top towards the cooler outlet. Therefore, within each cooler element, the number of locations where vortices occur is reduced, there is no stagnation phenomenon, and the loss of ventilation pressure is suppressed to a low level, thereby improving the heat exchange efficiency.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In Fig. 1, 1 is a cooler element, 3 is a cooler cover that houses this cooler element, 1c is an inner air ventilation passage, and 1d is an outer air ventilation passage, and each of these ventilation passages 1c and 1d is used for cooling. The container cover 3, the partition plate 2A, and the partition plate 2B are separated from each other as shown in FIG. 1b is an outside air ventilation path, 4 is a cooler inlet, and 5 is a cooler outlet. Moreover, FIG. 3 is a bottom view showing the whole cooler main body. Note that FIG. 4 is a cross-sectional view of a state in which the air cooler and the electric motor M are combined.

Next, the operation will be explained. First, the hot air generated inside the electric motor M circulates inside the electric motor M,
Internal circulating air is sent from the cooler inlet 4 of the cooler element 1 into the air passages 1c and 1d by the pressure generated by the internal circulating air fan 14, respectively. The hot air passing through the inside air ventilation paths 1c and 1d exchanges heat with the outside air flowing through the outside air ventilation path 1b via the element partition wall, becomes cooling air, and returns to the inside of the bracket 11 of the electric motor M through the cooler outlet 5. . In this case, the hot air as the inside air flows inside each cooler cover 1 from the cooler inlet 4 to the cooler outlet 5, dividing into two inside and outside inside air ventilation passages 1c and 1d, and this flow There are no parts on the way that would obstruct the
Since there are no swirls or stagnation phenomena during the flow, and the pressure loss is small, the inside air can smoothly pass through the cooler cover 1, and the flow rate becomes faster. and electric motor M
When the cooling air from the external circulating air fan 15 attached to the outside of the cooler element 1 passes through the inside of the cooler element 1, the inside air,
Heat exchange between the outside air is performed with high efficiency, thus improving the average heat transfer coefficient and improving the cooling efficiency of the main body of the electric motor M.

0010

As described above, according to the present invention, the flow of hot air sent from the electric motor through the cooler inlet is not obstructed between the gaps between the cooler elements and between the cooling elements and the cooler cover. Since the structure is configured to provide a plurality of internal air ventilation channels that smoothly divide the air, it is possible to prevent hot air from swirling or stagnating inside the cooler cover. Heat exchange can be carried out efficiently, and as a result, the cooling efficiency of the electric motor is improved, and burnout accidents of magnetic circuits and the like can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing a cooling device for an electric motor according to an embodiment of the present invention.

FIG. 2 is a side sectional view of the cooling device shown in FIG. 1;

FIG. 3 is a bottom view of the cooling device shown in FIG. 1;

FIG. 4 is a side sectional view of essential parts of the cooling device of FIG. 2 attached to an electric motor.

FIG. 5 is a front sectional view showing a conventional electric motor cooling device.

FIG. 6 is a side sectional view of the cooling device shown in FIG. 5;

7 is a side sectional view of the cooling device of FIG. 6 attached to an electric motor; FIG.

[Explanation of symbols]

1 Cooler element 1c Internal ventilation duct 1d Internal air ventilation duct 2A Partition plate 2B Partition plate 3 Cooler cover 4 Cooler inlet 5 Cooler outlet In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] Claim 1: A plurality of cylindrical cooler elements arranged in parallel inside a cooler cover so as to penetrate through the cooler element, through which outside air for cooling passes, gaps between the cooler elements, and the cooler. A plurality of internal air ventilation paths are separated by partition plates between the element and the cooler cover, and the hot air sent from the electric motor is smoothly divided so as not to be obstructed. A cooling device for an electric motor, comprising a cooler inlet for feeding hot air, and a cooler outlet for returning the cooled air to the electric motor after the hot air is brought into contact with the cooler element.