JPH0226452B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air gap winding rotating electrical machine in which a stator coil is mounted on the slotless inner peripheral portion of a magnetic shield on the stator side.

In recent years, in rotating electric machines, due to the increase in unit capacity and the development of superconducting rotating electric machines, air gear winding, in which a stator coil is installed without a slot on the stator side, has been adopted.

The air gear winding rotating electric machine is characterized by the fact that there are no teeth on the stator core, so the stator coil is placed in the air gap to increase the space factor, making effective use of the empty space. For example, the magnetic flux density of the part can be increased. However, the lack of slots makes it difficult to retain the stator coils.

This type of air gap winding rotary electric machine according to the prior art is shown in FIGS. 1 and 2 as a longitudinal sectional view and an enlarged front sectional view of the air gap winding portion. 1 is a magnetic shield formed into an integral cylindrical shape by laminating many silicon steel plates, etc., and both ends are held down by end plates 2.
It is held within a stator frame (not shown).
The inner circumferential surface of the magnetic shield 1 has no slot, but a locking protrusion 1a provided in the axial direction is provided.
are arranged at multiple locations in the circumferential direction. 3
is an insulating inner cylinder shaped to surround the outer circumference of the rotor 10 at intervals, and is made of, for example, epoxy resin glass fiber material or epoxy resin glass cloth material,
It is wound and formed into a cylindrical shape. 4 is the insulating inner cylinder 3
A large number of stator coils are placed on the outer circumference of the
A case of two-layer winding is shown, consisting of an upper opening 4a and a lower opening 4b. Reference numeral 5 denotes an insulating press plate applied to the outer periphery of each stator coil 4, which is divided into a plurality of parts in the circumferential direction, and is made of, for example, an epoxy resin glass cloth laminate. Reference numeral 6 denotes an interlayer insulating plate inserted between the upper opening 4a and the lower opening 4b, and 7 and 8 denote insulating spacing pieces fitted between the respective stator coils 4, which are made of, for example, an epoxy resin glass laminate. Among these, the insulating spacer piece 8 is disposed at a position corresponding to the locking protrusion 1a of the magnetic shield, and an engaging protrusion 8 is provided on one side of the upper part.
a is formed, and is received in the circumferential direction by the locking protrusion 1a. These insulating spacing pieces 8 prevent the stator coil 4 from moving in the circumferential direction due to electromagnetic force. Reference numeral 9 denotes a pair of tapered key-shaped wedges driven in the axial direction between the inner peripheral part of the magnetic shield 1 and the insulating holding plate 5, and 2 wedges in the thickness direction.
It is divided and both joint surfaces are formed at an angle, and in the example shown in the figure, it is divided into two sets in the axial direction, and is arranged over the entire circumference in the circumferential direction except for the locking protrusion 1a. These wedges 9 are made of an insulating material with high mechanical strength, are driven in the axial direction, generate compressive force in the radial direction, and firmly press and fix the stator coil 4.

As shown in FIG. 2, from the point of application of the force _W1 of the upper opening 4a and the point of application of the force _W2 of the lower opening 4b to the insulating spacing piece 8, the receiving point of the locking protrusion 1a of the magnetic shield 1 is The distances L ₃ and L ₄ to C are becoming smaller. This reduces the moment acting on the insulating spacer piece 8 to cause it to rotate, thereby eliminating the risk of damage to the engaging protrusion 8a and buckling of the insulating inner cylinder 3.

However, the insulating spacing pieces 8 are arranged at a plurality of locations in the circumferential direction, and the circumferential distance between each engagement protrusion 8a and each locking protrusion 1a of the magnetic shield 1 that corresponds to and receives the engagement protrusion 8a is It is extremely difficult to eliminate all directional gaps due to the manufacturing accuracy and assembly accuracy of both protrusions. If there are many gaps between the two protrusions, when a large force is generated to move the stator coil 4 in the circumferential direction due to a sudden short circuit, etc., the load will concentrate on the areas with no gaps. Projections 1a and 8a at that location
Excessive stress is generated in the stator coil 4, the insulating inner cylinder 3, etc., and if the limit of mechanical strength is exceeded, damage will occur.

This invention is provided on each of the locking protrusions on the inner circumference of the magnetic shield and each of the insulation spacing pieces fitted between the stator coils, and is provided on each of the locking protrusions on the inner circumference of the magnetic shield so as to be received in the circumferential direction corresponding to the locking protrusions. Drive wedges in the axial direction into the gaps between the locking protrusions and the engaging protrusions to eliminate the gaps between all the locking protrusions and each engaging protrusion, even if a large force is generated in the circumferential direction on the stator coil. The object of the present invention is to provide a highly reliable air gear winding rotating electrical machine that eliminates damage to each locking projection, each engagement projection, stator coil, insulating inner cylinder, etc.

FIG. 3 is an enlarged sectional view of the engaging portion between the magnetic shield and the insulating spacing piece, showing one embodiment of the present invention.
a, 4, 5, and 9 are the same as those in the prior art described above. Further, the insulating inner cylinder 3, the interlayer insulating plate 6, and the insulating spacer piece 7 are the same as those in FIGS. 1 and 2, and are omitted from illustration. 11 is arranged at a position corresponding to the locking protrusion 1a of the magnetic shield 1, and the stator coil 4
The engaging protrusion 11a on one side of the outer periphery of the insulating spacing piece fitted therein faces the locking protrusion 1a with a gap in the circumferential direction. Insulating spacing piece 11
is made of an insulating material with high mechanical strength, such as an epoxy resin glass cloth laminate. 12 is each locking protrusion 1
a and each engagement protrusion 11a in the axial direction.
It is divided and the joint surfaces of both sides are formed on a slope.
It is made of an insulating material with high mechanical strength, such as an epoxy resin glass cloth laminate. The wedge 12 is shown in perspective view in FIG. Reference numeral 13 denotes a protective sheet made of an insulating material pasted with adhesive on the side of the locking protrusion 1a of the magnetic shield 1 corresponding to the wedge 12, which covers the unevenness on the side surface of the locking protrusion 1 and prevents the wedge 12 from being driven in. To reduce dynamic friction, a thin laminate of epoxy resin glass cloth, for example, is used.

In this way, the protective sheet 13 is attached to the locking protrusion 1a.
The stator coil 4 is arranged in the insulating inner cylinder 3 by attaching the stator coil 4, and the assembly including the insulating spacing pieces 7 and 11 is inserted into the inner periphery of the magnetic shield 1, and the wedge 9 is driven into the radial direction. After fixing, the wedge 12 is driven between the locking projection 1a and the engaging projection 11a, and since the protective sheet 13 is applied to the locking projection 1a, driving can be done easily. The thickness of the wedge 12 may vary depending on the thickness of both protrusions 1.
It is also possible to determine the gap between a and 11a based on the actual item.

The magnetic shield 1 is generally formed by laminating silicon steel plates, and has irregularities on the side surface of the locking projection 1a. For this reason, the coefficient of friction against driving the wedge is extremely high, but by applying the protective sheet 13, the force required for driving the wedge can be reduced.
Furthermore, damage to the insulating varnish coating applied to the side surface of the locking protrusion 1a of the magnetic shield 1 is prevented. If this insulating varnish coating is damaged, overcurrent loss may occur in the magnetic shield 1 and it may burn out due to overheating, but this is prevented by the protective sheet 13.

Furthermore, if a low-friction sliding sheet is inserted between the protective sheet 13 and the wedge 12, the wedge 1
The driving force in step 2 can be further reduced. Also,
A sliding sheet may be inserted between the pair of wedges 12, and the required driving force can be further reduced. As the sliding sheet, a low-friction fluororesin sheet or the like, such as a polytetrafluoroethylene material (trade name: Teflon), is used.

In addition, in the above embodiment, the protective sheet 13 was attached to the side surface of the locking protrusion 1a of the magnetic shield.
If the laminated surface has small irregularities, the protective sheet may be omitted.

Further, in the above embodiment, one pair of wedges 12 is used in the axial direction, but the wedges 12 may be divided into a plurality of wedges in the axial direction, and a plurality of pairs of wedges 12 may be used.

Further, in the above embodiment, the wedge 9 is used to fix the stator coil 4 to the magnetic shield 1, but other fixing means that press in the radial direction can also be used.

As described above, according to the present invention, each of the locking protrusions on the inner circumferential portion of the magnetic shield and each insulating spacing piece packed between the stator coils is provided with a circular ring corresponding to the locking protrusion. Wedges were driven in the axial direction into the gaps between the locking protrusions that are received in the circumferential direction, and all the gaps between both protrusions were filled, so the stator coil was firmly fixed in the circumferential direction and each locking It is possible to eliminate damage to the locking protrusion, each engaging protrusion, the stator coil, the insulating inner cylinder, etc., and improve reliability.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of an air gear winding section showing an air gear winding rotary electric machine according to the prior art, FIG. 2 is an enlarged cross-sectional view taken along the - line in FIG. An enlarged sectional view of a locking portion of a magnetic shield and an insulating spacer, showing an air gear winding rotating electrical machine according to an embodiment;
4 is a perspective view of the wedge of FIG. 3; FIG. In the figure, 1... Magnetic shield, 1a... Locking protrusion, 3... Insulating inner cylinder, 4... Stator coil, 7... Insulating spacing piece, 9... Wedge, 11...
Insulating spacing piece, 11a...engaging protrusion, 12...wedge, 13...protective sheet. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] 1. A plurality of stator coils are arranged on the outer periphery of an insulating inner cylinder, an insulating spacing piece is fitted between these stator coils in the circumferential direction, and this assembly is placed on the inner periphery of a magnetic shield. In a rotating electrical machine in which the stator coil portion is fixed by a fixing means that presses in the radial direction between the inner circumferential portion of the magnetic shield and the outer circumferential side of each of the stator coils, the magnetic Locking protrusions in the axial direction are arranged on the inner circumference of the shield at multiple locations in the circumferential direction, and the outer circumferential An engaging protrusion is provided on one side of the locking protrusion to face the locking protrusion with a circumferential gap therebetween, and a wedge is driven into these gaps in the axial direction and fixed, and the radial fixing means is the locking protrusion. An air gear winding rotating electric machine characterized in that the air gear is disposed at a position in the circumferential direction excluding the engagement protrusion and the engagement protrusion. 2. The air gear winding according to claim 1, characterized in that a protective sheet is pasted on the surface of the locking protrusion of the magnetic shield facing the wedge side to reduce the required driving force of the wedge. Rotating electric machine. 3. The air gear winding rotating electric machine according to claim 2, wherein the protective sheet is made of an epoxy resin glass cloth laminate. 4. The air gap winding rotating electric machine according to claim 2 or 3, wherein the wedge is driven in with a sliding sheet inserted between the wedge and the protective sheet. 5 The wedge consists of a pair of tapered key-shaped wedges divided into two in the thickness direction, and a sliding sheet is provided between the wedge and the locking protrusion side and between the wedges, at least between the wedges. An air gear winding rotating electric machine according to any one of claims 1 to 4, characterized in that the air gear is inserted and driven. 6. Claim 4 or 5, characterized in that the sliding sheet is made of a fluororesin sheet.
The air gear winding rotating electrical machine described in Section 1.