JP2535870Y2 - Dovetail key device for salient pole rotating electric machine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dovetail key device of a salient-pole rotating electric machine such as a vertical shaft generator.
In particular, the present invention relates to a dovetail key for preventing a dovetail key device from being loosened by a pressing screw.

[0002]

2. Description of the Related Art A conventional dovetail key device used for a vertical shaft generator is shown in FIGS.

As shown in FIG. 2 (a), a rotor rim (2) is fitted on a shaft (1) of a vertical shaft type generator, and an outer peripheral portion of the rotor rim (2) is arranged as shown in FIG. 2 (b). As shown, a plurality of dovetail grooves (3) are provided, and a pole iron (4) wound with a pole coil (7) is engaged with every other dovetail groove (3), and the remaining dovetail grooves are engaged. A dovetail key (5) is engaged with (3).

As shown in FIG. 2 (c), the dovetail key (5) has a screw hole into which a pressing bolt (6) is screwed, and the pressing bolt (6) presses the bottom of the dovetail groove (3). By doing so, the dovetail key (5) is crimped and fixed to the dovetail groove (3).

The dovetail key (5) has a pole coil connecting plate (8) for connecting the pole coils (7) to each other.
Is fixed by tightening the bolt (9) into the screw hole (10).

In some large-capacity high-speed vertical generators, the centrifugal force of the pole coil connection plate (8) reaches 15 tons. The dovetail key (5) subjected to such a large centrifugal force moves by Δu due to the deformation of the dovetail groove (3) as shown in FIG. In this case, if the moving amount Δu of the dovetail key (5) is larger than the contraction amount of the pressing bolt (6) due to excessive centrifugal force, the pressing bolt (6)
The pressing force is lost, resulting in loosening. When the pressing bolt (6) is loosened, the dovetail key (5) is also loosened in a chain,
There is a risk of crack damage to the pole coil connection plate (8) during operation of the generator.

FIG. 3 (b) shows a solution to the above danger.
The following dovetail key has been proposed (Japanese Utility Model 1-39074). The dovetail key (5) has a groove larger than the diameter of the screw hole on the lower end surface side of the penetrating screw hole on the rotor rim side.
Or a hole is provided, in which a longer The lugs of the pressing bolt (6) as indicated by l ₂ of FIG. 3 (b). in this way,
By increasing the length of only the pressing bolt (6) that can be freely extended and contracted without being screwed into the dovetail key (5), the amount of contraction due to the pressing force can be made sufficiently larger than Δu, and loosening due to excessive centrifugal force It is to prevent.

[0008]

However, in the above-mentioned conventional structure, the effective screw length with which the dovetail key (5) and the pressing bolt (6) are screwed decreases, and it becomes impossible to maintain an excessive pressing force. In addition, the diameter of the pressing bolt (6) could not be increased, and there was a drawback that it did not work effectively against a very large centrifugal force, and it could not be a complete solution.

An object of the present invention is to solve these problems, and it is an object of the present invention to provide a dovetail key device for a salient-pole rotating electric machine that is highly safe even in a high-speed operation state.

[0010]

In order to achieve the above-mentioned object, the present invention provides a pole between a rotor rim fixed to the outer periphery of a shaft and a plurality of pole coils attached to the outer periphery of the rotor rim. A dovetail key for attaching a coil connection plate, wherein the dovetail groove formed on the outer periphery of the rotor rim is pressed by a pressing screw screwed to the dovetail key, and the dovetail key is crimped and fixed to the dovetail groove. 2 provided on dovetail key
A hole fitting that is fixed to the rotor rim has a tapered head between pieces of the pressing screw penetrates provided, through is in the hole
A round key embedded in the dovetail key in both directions perpendicular to the axis located at the tapered head of the metal fitting.
In addition , the surface in contact with the tapered head of the round key is configured to convert the displacement due to the centrifugal force in the direction perpendicular to the axis.

[0011]

[Function] Even if the dovetail groove is deformed by centrifugal force and the dovetail key moves to the outer peripheral side, the bolt with the tapered head remains fixed, so the round key in contact with the tapered part moves to the outer periphery of the dovetail key. The round key is pressed for a length equivalent to the amount of movement of the dovetail key, and the dovetail key is fixed by pressing it against the side of the deformed dovetail groove. do not do.

[0012]

An embodiment according to the present invention will be described with reference to FIG.

FIG. 1C is a longitudinal sectional view of the dovetail key device . FIG. 1A is a sectional view taken along the line II of FIG.
(B) shows a state where the dovetail groove is deformed by centrifugal force.
FIG. 2 is a sectional view taken along the line I.

As shown in FIG. 1C, a screw hole (1) into which a pressing bolt (6) passing through the dovetail key (5) is screwed.
A hole (12) is provided between the adjacent screw hole (11) and this hole (1).
2) a bolt (14) having a tapered head (13) which is fastened and fixed to the rotor rim (2) through
As shown in (d), round keys (15A, 15B) are embedded in the dovetail key (5) located on the tapered head (13) from both sides in a direction perpendicular to the axis. This round key (15A, 15B)
The surface in contact with the tapered head (13) receives the displacement of the dovetail key (5) due to the centrifugal force and converts it into a pressing force in the direction perpendicular to the axis. The other surface of the round key (15A, 15B) is made equal to the side inclined surface of the dovetail key (5).

With the above structure, the dovetail groove (3) is deformed by centrifugal force, and when the dovetail key (5) moves Δu 'to the outer peripheral side as shown in FIG. Tapered head to stay fixed
The round keys (15A, 15B) in contact with (13) are shifted in the direction perpendicular to the axis according to the amount of movement Δu 'of the dovetail key (5) to the outer periphery.
Pressing the round key (15) by v and pressing the side of the deformed dovetail groove (3) to fix the dovetail key (5), the dovetail key (5) moves more than the shrinkage of the pressing bolt (6). However, the dovetail key (5) does not loosen.

[0016]

As described above, according to the present invention, a bolt having a tapered head provided between the dovetail key pressing bolts is tightened to the rotor rim, and a round key is provided at right angles to the bolt so as to be in contact with the tapered portion. By providing,
With the movement of the dovetail key to the outer peripheral side due to centrifugal force, the round key can also press the side surface of the dovetail key, thereby preventing the dovetail key from loosening. As a result, crack damage of the pole coil connection plate can be prevented,
The safety of this type of rotating electric machine can be improved.

[Brief description of the drawings]

FIG. 1 shows a dovetail key device of a salient-pole rotating electric machine according to the present invention.
Block diagram of an embodiment of location.

FIG. 2 is a configuration diagram of a conventional dovetail key device of a salient pole rotating electric machine.

FIG. 3 is a detailed view of a main part of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Shaft 2 ... Rotator rim 3 ... Dovetail groove 4 ... Hall core 5 ... Dovetail key 6 ... Pressing bolt 7 ... Pole coil 8 ... Pole coil connection plate 9 ... Connection plate pressing bolt 10 ... Dowel tail screw hole 11 ... For pressing bolt Screw hole 12 ... Hole 13 ... Taper 14 ... Bolt 15A, 15B ... Round key

Claims (1)

(57) [Scope of request for utility model registration] 1. A dovetail key for mounting a pole coil connection plate between a plurality of pole coils attached to an outer periphery of a rotor rim and a rotor rim fixed to an outer periphery of a shaft. In a device in which a dovetail groove formed on the outer periphery of the rotor rim is pressed by a mating pressing screw and the dovetail key is fixed to the dovetail groove by crimping, a tapered head is provided between pressing screws provided on the dovetail key. a hole fitting that is fixed to the rotor rim has penetrates provided, said to be through to the hole
A round key embedded in the dovetail key is brought into contact with both the direction perpendicular to the axis located at the tapered head of the metal fitting ,
A dovetail key device for a salient-pole rotating electric machine, wherein a displacement caused by centrifugal force is converted in a direction perpendicular to an axis by a surface of the round key which is in contact with a tapered head.