JP2002039794A - Rotor protection structure of reluctance resolver - Google Patents

Abstract

(57) [Summary] Even if a fluid enters a resolver rotor, the rotor pieces can be prevented from being separated from each other or displaced from each other. An outer edge of a resolver rotor is held by a rotor protection cover. The rotor protection cover 19 is composed of two parts, a case 20 and a lid 21, and a rotor tooth 13 a of the resolver rotor 13 is provided on the inner periphery of the case 20.
Is formed. Case 2
By mounting the resolver rotor 13 on the cover 0 and closing the opening with the lid 21 and welding the resolver rotor 13, the resolver rotor 13 is held in the rotor protection cover 19, and separation and displacement between the rotor pieces 18 are prevented. .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor protection structure for a reluctance resolver in which the outer edge of a rotor is covered with a protective cover to prevent separation and displacement of rotor pieces.

[0002]

2. Description of the Related Art Conventionally, a reluctance resolver for detecting a rotation speed and a phase of a rotor for controlling the speed of an electric motor is known from Japanese Patent Application Laid-Open No. H11-98769.

FIG. 10 schematically shows a circuit configuration of a general reluctance resolver. A resolver rotor 1 that rotates synchronously with a motor rotor of an electric motor (not shown) and a resolver stator 2 that incorporates the resolver rotor 1 are made of a magnetic material, and have magnetic poles provided on the resolver stator 2.
The excitation coil 4 and the detection coils 5a and 5b are wound to form a normal one-phase excitation two-phase output type coil. In the figure, a pair of rotor teeth 1a of the resolver rotor 1 are formed diagonally.

When the resolver rotor 1 rotates synchronously with the motor rotor of the electric motor, the gap permeance between the resolver rotor 1 and the magnetic poles of the resolver stator 2 changes. At this time, when the exciting coil 4 is excited with an AC voltage, a reluctance fluctuation with one rotation of the resolver rotor 1 as one cycle generates a sine wave induced voltage corresponding to the position of the resolver rotor 1 in the detection coils 5a and 5b. . By calculating the change in the induced voltage and the difference between the electromotive forces detected by the two detection coils 5a and 5b, the rotation speed and rotation angle of the motor rotor that rotates synchronously with the resolver rotor 1 can be detected.

By the way, as shown in FIGS. 11 and 12,
In general, the resolver rotor 1 has a multilayer structure in which rotor pieces 3 formed by punching out an electromagnetic steel sheet are laminated, and the rotor pieces 3 are joined by using a method such as bonding or caulking. The resolver rotor 1 shown in FIG. 1 has rotor teeth 1a formed in two directions on its outer periphery that are perpendicular to each other.

Recently, an adhesive steel sheet having an adhesive layer coated on both sides in advance is used as an electromagnetic steel sheet, and the electromagnetic steel sheet (adhesive steel sheet) is punched to form rotor pieces, and the rotor pieces are laminated. Thereafter, a technique is also known in which the adhesive layer is melted by heat treatment and joined to simplify the manufacturing process.

[0007]

By the way, the reluctance type resolver electrically detects the change in the gap permeance between the resolver rotor and the magnetic pole of the resolver stator by the rotation of the resolver rotor. Since the rotation angle and the rotation speed of the (motor rotor) are determined, if the rotor pieces constituting the resolver rotor 1 are separated and each rotor piece is displaced, the rotation angle and the rotation speed of the motor rotor are accurately determined. And it is difficult to properly control the electric motor.

In a normal use mode, each rotor piece does not peel off. However, for example, when the electric motor is used in an environment where fluids such as cooling water and lubricating oil are easily mixed, such as a hybrid car, The resolver rotor attached to the electric motor easily comes into direct contact with cooling water, lubricating oil, or the like, and when a fluid enters the resolver rotor 1, each rotor piece may peel off. Therefore, when the resolver is used in such an environment, it is necessary to sufficiently consider the durability of the adhesive and the like, and there is a problem that the cost is increased because the material is limited.

In this respect, when the rotors are joined by caulking, the rotor pieces do not peel off even when the fluid enters, but the magnetic properties are easily deteriorated in the caulked portion, and the detection accuracy is reduced. You have to sacrifice to some extent.

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention provides a rotor for a reluctance resolver that can effectively prevent separation between rotor pieces due to infiltration of a fluid while maintaining detection accuracy, and can achieve high reliability. The purpose is to provide a protective structure.

[0011]

In order to achieve the above object, a rotor protection structure for a reluctance resolver according to the present invention has a reluctance having a rotor formed by laminating a plurality of rotor pieces and a stator containing the rotor. In the mold resolver, the outer edge of the rotor is held by a protective cover.

In such a configuration, since the outer edge of the rotor is held by the protective cover, the rotor pieces are not separated from each other or displaced from each other even when the rotor pieces are not connected to each other.

[0013] In this case, preferably, 1) the protective cover can be divided into at least two parts. 2) The protective cover is formed by molding with a resin mold. 3) The rotor teeth formed on the outer periphery of the rotor are exposed from the protective cover.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 to 5 show a first embodiment of the present invention. FIG. 1 is a perspective view of a reluctance resolver, and FIG. 2 is a sectional view taken along line II-II of FIG.

The reluctance resolver 11 is provided in parallel with an electric motor (not shown). The resolver 11 has a multilayer structure of a resolver stator 12 and is rotatably disposed on the inner periphery of the resolver stator 12. And a rotating resolver rotor 13.

A well-known coil 14 of a one-phase excitation / two-phase output type is wound around a magnetic pole (not shown) provided on the inner periphery of the resolver stator 12, and each coil 14 is connected via a lead wire 15. To the external connector 16. Further, the resolver stator 12 and the coil 1
4 is covered with a coil protection cover 17.

The resolver rotor 13 is formed by laminating a plurality of rotor pieces 18 formed by stamping out an electromagnetic steel sheet. As shown in FIG. 3, the outer peripheral surface of the resolver rotor 13 has the same sinusoidal shape. (Four in the present embodiment) are formed at equal intervals.

As shown in FIGS. 3 to 5, the outer edge of the resolver rotor 13 has a rotor protective cover 19 having magnetic permeability.
Covered with. The rotor protection cover 19 has a concave portion 20a formed therein for positioning the rotor teeth 13a of the resolver rotor 13 on an inner periphery thereof. The rotor protective cover 19 is mounted on the open end face of the case 20, and is welded or fitted to the case 20. And a lid 21 to be fixed.

In such a configuration, a plurality of rotor pieces 1
8 is mounted on the case 20 of the rotor protection cover 19, and then a lid 21 is mounted on the opening of the case 20, and the lid 21 and the bottom of the case 20 are Both sides of the resolver rotor 13 are sandwiched, and the lid 21 is fixed to the case 20 by welding or fitting.

A resolver rotor 1 is provided on the inner periphery of the case 20.
Since the concave portion 20a for positioning the rotor teeth 13a formed on the outer periphery of the rotor 3 is formed, the resolver rotor 13 does not rotate in the case 20, and is held and fixed in a reliably positioned state.

The resolver rotor 13 covered with the rotor protection cover 19 is accommodated in the inner periphery of the resolver stator 12 and connected to the motor rotor of the electric motor so as to be able to rotate synchronously.

As described above, according to the present embodiment, the resolver rotor 13 having a multilayer structure is covered with the rotor protection cover, and the resolver rotor 13 is covered with the rotor protection cover 19.
Is fixed inside the resolver rotor 13.
Even when a fluid such as cooling water, lubricating oil or the like enters, the rotor pieces 18 do not peel off and do not displace, thereby improving durability and obtaining high reliability.

Therefore, it is not necessary to connect the rotor pieces 18 constituting the resolver rotors 13 to each other, and each of the rotor pieces 18 can be accommodated in the rotor protection cover 19 in a non-coupled state, thereby reducing the number of work steps. Can be.

Of course, there is no problem if the rotor pieces 18 are integrated in advance by bonding or caulking.
Further, the rotor piece 18 may be formed by punching an adhesive steel sheet having an adhesive layer formed on the surface of an electromagnetic steel sheet.

FIGS. 6 and 7 show a second embodiment of the present invention. The rotor protection cover 19 shown in the first embodiment is composed of two parts, a case 20 and a lid 21. The rotor protection cover 25 shown in the present embodiment is a molded product.

That is, the resolver rotor 13 having a multilayer structure
Is placed in a mold, and after closing the mold, a resin having magnetic permeability is poured into the mold. Then, the resin flows into the cavity formed between the inner surface of the forming die and the resolver rotor 13, and as shown in FIGS. 6 and 7, a rotor protection cover 25 made of a resin mold is formed on the periphery of the resolver rotor 13. You.

The inner peripheral surfaces of the rotor protection cover 25 are formed along the rotor teeth 13a formed on the outer periphery of the resolver rotor 13 during molding, so that they are positioned with respect to each other.
The rotor protection cover 25 and the resolver rotor 13 do not move relative to each other, and are satisfactorily held and fixed.

As described above, according to the present embodiment, since the rotor protection cover 25 is a resin molded product, the rotor protection cover 25 and the resolver rotor 13 are integrated,
Handleability is improved.

Further, since the outer edge of the resolver rotor 13 is covered with the resin mold, even if the fluid enters the resolver rotor 13, the rotor pieces 18 constituting the resolver rotor 13 do not peel off. Therefore, the rotor pieces 18 do not need to be connected to each other, and can be integrated by a resin mold without being connected to each other.
Manufacturing becomes easier.

Of course, also in this case, each rotor piece 1
There is no problem even if 8 is integrated in advance by bonding or caulking. Further, the rotor piece 18 may be formed by punching an adhesive steel sheet having an adhesive layer formed on the surface of an electromagnetic steel sheet.

FIGS. 8 and 9 show a third embodiment according to the present invention. The rotor protection cover 25 shown in the second embodiment is molded so as to cover the entire outer periphery of the resolver rotor 13, but the rotor protection cover 26 according to the present embodiment exposes the tops of the rotor teeth 13a. In this state, the mold is formed in the state.

As described above, in this embodiment, the top of the rotor teeth 13a of the resolver rotor 13 is exposed from the rotor protection cover 26, so that the resolver stator 12 (see FIG. 1)), the air gap between the magnetic pole formed on the inner circumference of the rotor and the rotor teeth 13a can be reduced, so that the detection accuracy is improved.

[0033]

As described above, according to the present invention,
Since the outer edge of the rotor is held by the protective cover, peeling of the rotor piece due to intrusion of fluid can be effectively prevented, and high reliability can be obtained.

Further, by exposing the rotor teeth formed on the outer periphery of the rotor from the protective cover, it is possible to prevent the detection performance from lowering.

[Brief description of the drawings]

FIG. 1 is a perspective view of a reluctance resolver according to a first embodiment.

FIG. 2 is a sectional view taken along the line II-II of FIG.

FIG. 3 is a front view of the resolver rotor held by the rotor protection cover.

FIG. 4 is a sectional view taken along the line IV-IV of FIG. 3;

FIG. 5 is an exploded perspective view of the rotor protection cover and the resolver rotor.

FIG. 6 is a front view of a resolver rotor held by a rotor protection cover according to a second embodiment.

7 is a sectional view taken along the line VII-VII of FIG. 6;

FIG. 8 is a front view of a resolver rotor held by a rotor protection cover according to a third embodiment.

9 is a cross-sectional view taken along the line IX-IX of FIG.

FIG. 10 is a circuit diagram of a conventional reluctance resolver.

FIG. 11 is a front view of the resolver rotor.

FIG. 12 is a sectional view taken along the line XII-XII of FIG. 11;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Reluctance type resolver 12 Resolver stator 13 Resolver rotor 13a Rotor tooth 18 Rotor piece 19, 25, 26 Rotor protection cover

Claims (4)

[Claims] 1. A reluctance resolver having a rotor formed by laminating a plurality of rotor pieces and a stator containing the rotor, wherein the outer edge of the rotor is held by a protective cover. Rotor protection structure. 2. The structure for protecting a rotor of a reluctance resolver according to claim 1, wherein said protective cover can be divided into at least two parts. 3. The structure for protecting a rotor of a reluctance resolver according to claim 1, wherein the protective cover is formed by resin molding. 4. A rotor protection structure for a reluctance resolver according to claim 1, wherein rotor teeth formed on the outer periphery of said rotor are exposed from said protection cover.