JPS61207151A - Three-phase induction motor - Google Patents

Abstract

PURPOSE:To prevent the insulating coats of coils from being damaged due to the insertion, by making the wire diameter of the coil inserted previously, larger than that of the coil inserted later. CONSTITUTION:Three phase windings 7 are inserted in a slot 2 getting out of phase very 120 deg. on the outer peripheral side. Among the three phase windings 7, the peripheral length of an outer coil L 8 inserted first is arranged to be the largest, and that of an intermediate coil M 9 inserted second is arranged to be smaller, and that of an inner coil S 10 inserted finally is arranged to be the smallest. The wire diameter of the coil L 8 or the coil M 9 is arranged to be larger than that of the coil S 10. In this manner, the coils in place on the inner peripheral side can be smoothly inserted into the slot, and insulating coats can be prevented from causing layer short due to damage.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention relates to a three-phase induction motor in which a coil is inserted into a slot.

(B) Prior Art A conventional three-phase induction motor is generally shown in FIG. 2, and is constructed as follows.

That is, three-phase windings (3) having the same wire diameter are housed in slots (2) formed in the inner peripheral edge of the stator (1). These three-phase windings are sequentially inserted with a phase shift of 120° from the coil located on the outer circumferential side of the slot (2). Therefore, inside and outside the three-phase winding (3), the outer L coil (4) has the longest length, and the middle M coil (5
) has the second longest director, and the inner S coil (6) has the shortest director. And three coils (4) (5
)(6) have the same number of turns. (For example, JP-A No. 5
7-186939).

(c) Problems to be solved by the invention However, when the wire diameter is increased in order to improve motor performance, the three-phase winding (3) is finally inserted into the slot (2). (6) is difficult to insert into the slot (2) due to the pre-inserted L coil (4) and M coil (5), and if inserted forcibly, it will damage the insulation film of the coil and cause a short circuit. There was a problem.

In order to solve the above problem, this invention makes the wire diameter of the pre-inserted coil larger than the wire diameter of the coil to be inserted later, thereby improving motor performance while preventing damage to the coil's insulation film due to insertion. The purpose is to

B) Means for solving the problem This invention is a coil that is inserted sequentially from the outer circumference side, and the wire diameter of the coil inserted on the outer circumference side is made larger than the wire diameter of the coil inserted on the inner circumference side. It is.

(E) Function This invention improves motor performance by making the wire diameter of the coil inserted on the outer circumference side thicker than the wire diameter of the coil inserted on the inner circumference side, and the wire is inserted later into the slot. This allows the coil to be inserted smoothly into this slot.

(f) Example The present invention will be explained below based on the example shown in FIG.

(1) is a stator, and a slot (2) is provided on the inner peripheral edge of this stator. (7) is a three-phase winding inserted into the slot (2), and this winding is inserted into the slot (2) with a phase shift of 120 degrees from the outer circumferential side. Among the three-phase windings (7), the outer L coil (8) inserted first has the longest circumference, and the middle M coil (8) is inserted into the primary coil.
The coil (9) has the next longest length, and the inner S coil O inserted last has the shortest circumference. L carp/
The wire diameters of I/(8) and M coil (9) are made larger than the wire diameter of S coil αO.

In a three-phase induction motor configured in this way.

Among the three-phase windings (7) inserted into the slots (2) of the stator (1), the L coil (8) and M coil (9) inserted first are different from each other even if the wire diameter is increased. It is inserted smoothly, but the S coil (G) to be inserted last is inserted beforehand.
Coil (8) and M coil (9) make insertion difficult.

However, the S coil (g) is different from the other coils (8) (9).
), and the coil volume is smaller so that it can be stored in narrow spaces. for example,
The wire diameters of L coil (8) and M coil (9) are p 0.8
+ot, If the wire diameter of the S coil (g) is $0.75mm, the three-phase winding (7) will be inserted smoothly into the slot (2), and there is little risk of damaging the insulation film of this winding. . In addition, the L coil (8) with the longest circumference and the M coil with the next longest circumference
By increasing the wire diameter of the coil (9), even if the circumference becomes long, the resistance of the increased resistance can be reduced. Therefore, the resistance values of L coil (8) and M coil (9) are approximately equal to the resistance value of the shortest S coil (■) of the station, and the three-phase winding (7)
The resistance values are balanced, and the copper loss between the three phases is also balanced, and by simply increasing the wire diameter of some of the coils, the same motor performance as when all the coils have thicker wire diameters can be obtained.

In addition, in the above explanation, the L coil (8) and the M coil (
Although the explanation was given by increasing the wire diameter in 9), the wire diameter can be changed from L coil to M.
Coil>S coil, Al or L coil#>M coil=S
Needless to say, the same effect can be obtained in relation to the coils.

(G) Effects of the Invention The three-phase induction motor of the present invention has coils that are inserted sequentially from the outer circumferential side, and the wire diameter of the coil inserted on the outer circumferential side is made larger than the wire diameter of the coil inserted on the inner circumferential side. , because the coil volume of the coil inserted later is reduced.
The coil located on the inner circumferential side can be smoothly inserted into the slot, and layer shorts due to damage to the insulation film can be prevented, and motor performance can also be improved.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a stator showing an embodiment of the present invention;
FIG. 2 is a plan view of a stator showing a conventional example. (1)...Stator, (2)...Slot, (
7)...Winding, (8)...L coil, (9)-
M coil, Ca/S coil.

Claims (1)

[Claims] 1. In a three-phase induction motor, slots are provided on the inner circumferential edge of the stator, coils are sequentially inserted into the slots with a 120° phase shift, and the coil ends of the coils are overlapped. A three-phase induction motor characterized in that the wire diameter of the coil inserted on the inner and outer circumferential sides is larger than the wire diameter of the coil inserted on the inner circumferential side.