JP2573685Y2 - Reluctance motor rotor - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor of a reluctance motor formed by laminating silicon steel plates in an axial direction.

[0002]

2. Description of the Related Art Conventionally, in a rotor core of a reluctance motor in which even-numbered salient poles projecting in a radial direction are provided at equal intervals in a circumferential direction, damper grooves extending parallel to both side surfaces of the salient poles are provided at the tip of the salient poles. A device provided nearby is disclosed (for example, Japanese Utility Model Laid-Open No. 1-162768).

[0003]

The reluctance motor has a shaft (hereinafter, referred to as a "straight axis") directed toward the outer periphery of the salient poles and a shaft (hereinafter, referred to as "horizontal axis") which is electrically rotated by 90 degrees with respect to the straight axis. The relationship between the inductance and the torque T is expressed by the following equation (1). _{T = (L d -L q)} i d · i q ... (1) where, L _d: direct-axis inductance L _q: horizontal axis inductance i _d: direct-axis current i _q: quadrature axis current therefore direct-axis inductance by reducing the horizontal axis inductance L _q by increasing the L _d torque T increases. However, in the above configuration, since the conductor is inserted into the damper groove, the damper grooves are arranged in a line along the horizontal axis. The magnetic resistance in the direction perpendicular to the direction becomes equal. As a result, there is a disadvantage that the horizontal axis inductance _Lq increases and the torque decreases. This invention is to reduce the horizontal axis inductance L _q, it is an object to prevent the decrease in the torque of the reluctance motor.

[0004]

According to the present invention, there is provided a rotor for a reluctance motor having a plurality of salient poles. A plurality of slits arranged in a direction mechanically perpendicular to a straight axis are provided in a plurality of stages, and the slits are arranged so that a distance between adjacent slits in a straight axis direction is smaller than a length of the slit.

[0005]

Since a plurality of slits extending in the axial direction are provided from the vicinity of the tip of the salient pole to the boss, the magnetic resistance in the horizontal axis direction is large and the horizontal axis inductance is small.
Therefore, the decrease in the torque of the reluctance motor is small due to the relationship between the inductance and the torque of the direct axis and the horizontal axis of the reluctance motor.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
FIG. 1 is a front view showing a rotor according to an embodiment of the present invention. In this case, the rotor 1 has four salient poles 3 radially arranged around an outer periphery of a boss portion 2.
Are formed by laminating a plurality of rotor cores 4 made of silicon steel plates to form four magnetic poles. Each of the salient poles 3 is provided with a plurality of slits 5 extending parallel to the direct axis direction and arranged in the horizontal axis direction from near the tip of the salient pole 3 to the boss portion 1.
A plurality of steps are formed in the straight axis direction up to 1, so that the interval between the adjacent slits 5 in the straight axis direction is smaller than the length of the slit 5. In the vicinity of the outer periphery of the boss 2, a plurality of slits 6 are formed concentrically with the outer periphery between the slits 5 provided in the adjacent salient poles 3. Incidentally, the relation between the horizontal axis inductance L _q and the horizontal axis direction of the magnetic resistance R _q is the number of turns of the exciting coil wound around the salient poles 3 and N, is expressed by the following equation (2). ^{_{L q = N 2 / R q}} ... (2) From this, a magnetic resistance R _q of the horizontal axis direction is large horizontal axis inductance L _q is seen that smaller. According to the above configuration, a plurality of slits 5 extending in parallel with the direct axis direction of the salient poles 3 and arranged in the horizontal axis direction are arranged in a plurality of steps at intervals in the vertical axis direction. The cross-sectional area of the magnetic path is small, and the magnetic resistance R in the horizontal axis direction is larger than the magnetic resistance _{Rd in the} horizontal axis direction.
_q becomes much larger, and the horizontal axis inductance L _q becomes extremely small according to the equation (2). Similarly, the slits 6 provided near the outer periphery of the boss portion 2 increase the magnetic resistance in the horizontal axis direction at the root of each salient pole 3. Therefore, it can be seen from Equation (1) that a decrease in the torque of the reluctance motor can be prevented. FIG. 2 shows another embodiment in which the slits 5 are arranged in a zigzag pattern, and the magnetic path between the plurality of slits 5 arranged in the straight axis direction is blocked by the row of the adjacent slits 5. Therefore, the magnetic resistance in the horizontal axis direction is further increased, and the decrease in torque can be further suppressed.

[0007]

As described above, according to the present invention, since a plurality of slits extending in the direct axis direction are provided from the vicinity of the tip of the salient pole to the boss, the magnetic resistance in the horizontal axis direction increases. This has the effect that the torque of the reluctance motor can be prevented from decreasing.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a front view showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotor 2 Boss part 3 Salient pole 4 Rotor core 5, 6 Slit

Claims (3)

(57) [Scope of request for utility model registration] 1. A rotor for a reluctance motor having a plurality of salient poles, wherein each of the salient poles extends in a direction parallel to a direct axis direction from a vicinity of a tip of the salient pole to a boss portion, and is mechanically perpendicular to the straight axis. A plurality of slits arranged in a direction are provided in a plurality of stages in the direct axis direction, and the slits are arranged such that the interval in the direct axis direction between adjacent slits is smaller than the length of the slits. Child. 2. The reluctance motor rotor according to claim 1, wherein the slits are arranged in a staggered manner. 3. The rotor for a reluctance motor according to claim 1, wherein a plurality of slits are provided concentrically with the outer periphery near the outer periphery of the boss portion.