JPH04161030A - Armature cooling structure - Google Patents

Abstract

PURPOSE:To cool an armature by coupling two silicon steel plates having slots in their inner and outer circumferences, fixing at least one couple of the plates to the axial center of the armature core, and making a heat radiation port to radiate heat generated in the armature winding. CONSTITUTION:A plurality of silicon steel plates 3 and 4 are laminated in sets of two so that the slots are arranged identically in the circumferential direction. A plurality of coupled plates are fixed to the axial center of an armature core to make an armature core. Thereby the slots of the armature core are not closed and a heat radiation port to radiate heat generated in the armature winding is made from the slots to the outer peripheral face of the armature core. Therefore, heat is hardly confined in the slots.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cooling structure for an armature of a motor such as a brushless motor used for various types of power.

[Prior Art] FIG. 7 shows an example of a conventional motor armature cooling structure. FIG. 7 is a cross-sectional view of the brushless motor assembled into a brushless electric motor. It consists of an armature winding 15 wound around a plurality of slots.

Heat dissipation from the armature windings was done either spontaneously or forcibly by blowing air into the motor using a fan or the like. Figure 7 shows the heat flow in the case of natural cooling with arrows. As shown in FIG. 7, the heat generated in the armature winding 15 within the slot flows axially within the slot to the coil end, or flows axially through the air gap between the rotor and the armature. was.

[Problems to be Solved by the Invention] However, in the conventional armature core formed by laminating multiple silicon steel plates of the same thrower shape, heat dissipation is poor near the shaft end of the armature core. Although this is relatively good, since almost all heat escapes only through the gap near the center in the axial direction, there is a problem in that heat tends to accumulate in the slot especially when the length of the motor in the axial direction is large.

In addition, when permanent magnets are used in the rotor and the permanent magnets are arranged on the rotor surface, if the heat of the armature winding flows only in the air gap direction, the temperature of the magnet surface tends to rise.
This not only deteriorates the magnetic properties of the magnet, but also poses a risk of thermal demagnetization of the magnet.

An object of the present invention is to eliminate the drawbacks of the prior art and to provide a cooling structure for an armature of an electric motor in which heat of the armature winding is radiated to the outside of the motor so that it is difficult to be trapped inside the slot and the heat is difficult to be transmitted to the surface of the magnet. It is something to do.

[Means for Solving the Problems] The IE armature cooling structure for an electric motor according to the present invention includes an armature core formed by laminating a plurality of circular silicon steel plates, and a plurality of armature cooling structures arranged on the armature core. The armature of a motor is composed of an armature winding wound around a slot, and a silicon steel plate having the same tooth width but a larger slot depth than the armature core, and a silicon steel plate on the outer circumference side in addition to the inner circumference. A set of two silicon steel plates provided with slots is stacked so that the positions of the slots are equal in the circumferential direction, and is inserted at least one place in the axially intermediate part of the armature core, and the armature winding is It is characterized by the provision of a heat dissipation port that radiates heat generated in the wire.

[Examples] Examples of the present invention will be described below based on the drawings. 1st
The figure is a sectional view of a state in which an armature of a motor according to an embodiment of the present invention is assembled into a brushless motor. FIG. 2 is a perspective view of the armature. 2 is a circular silicon steel plate having the same shape and has a plurality of slots 2a, and a plurality of sheets are laminated to form the armature core 1; 4 is a silicon steel plate having a large slot;
is a silicon steel plate with slots on the outer circumference in addition to the inner circumference, 5
are armature windings wound around a plurality of slots of the armature core 1. 6 is a permanent magnet rotor, 7 is a permanent magnet, 8 is a rotor shaft, and 9 is a housing.

FIG. 3 shows a plan view of the silicon steel plate 2, FIG. 4 shows a plan view of the silicon steel plate 3, and FIG. 5 shows a plan view of the silicon steel plate 4. Further, FIG. 6 shows a plan view when the silicon Ti4 plates 2, 3, and 4 are laminated in this order from the bottom. As shown in FIG. 6, two sets of silicon steel plates 3 and 4 are stacked so that the slot positions are the same in the circumferential direction, and a plurality of silicon steel plates are inserted in the axially intermediate part of the armature core. , forming the armature core.

Therefore, the slot of the armature core is not sealed, and a heat dissipation port is provided from the slot to the outer peripheral surface of the armature core to radiate heat generated in the armature winding.

Figure 1 shows the heat flow in the case of natural cooling with arrows. 1st
As shown in the figure, near the center in the axial direction, heat flows not only in the air gap direction but also from the heat dissipation port of the armature core.

Therefore, heat is less likely to be trapped inside the slot. Furthermore, since the heat transmitted in the air gap direction is also reduced, the influence of heat on the magnet is also reduced.

[Effects of the Invention] As described above, according to the present invention, since the armature core is provided with a heat dissipation port, it becomes difficult for heat generated in the armature winding to be trapped in the slot. In addition, since the heat transmitted in the air gap direction is also reduced, the effect of heat on the magnet is also reduced.
There is less risk of deterioration of magnetic properties and thermal demagnetization.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a state in which an armature of a motor according to an embodiment of the present invention is assembled into a brushless motor. Figure 2 is a perspective view of the armature. FIG. 3 is a plan view of the silicon steel plate 2. FIG. 4 is a plan view of the silicon steel plate 3. FIG. 5 is a plan view of the silicon steel plate 4. FIG. 6 is a plan view when silicon steel plates 2.3.4 are laminated. FIG. 7 is a sectional view of a conventional armature installed in a brushless motor. 1.11...Armature core 2.12...Silicon steel plate 2a...Slot 3...
......Silicon steel plate 3a...
...Slot 4...Silicon steel plate 5.15...Armature winding 6.16...Permanent magnet rotor 7.17 ...Permanent magnet 8.18 ...Rotor shaft 9.19 ...More than housing

Claims (1)

[Claims] In the armature of a motor, the armature includes an armature core formed by laminating a plurality of circular silicon steel plates, and an armature winding wound around a plurality of slots arranged in the armature core. A silicon steel plate with the same tooth width but a larger slot depth compared to the armature core, and a silicon steel plate with slots on the outer circumference in addition to the inner circumference are used as a set, and the slot positions are set relative to the circumferential direction. An armature characterized in that a plurality of sheets are laminated equally, and a heat dissipation port is provided in at least one place in the axially intermediate part of the armature core to dissipate heat generated in the armature winding. Cooling structure.