JPS6020763A - Rotor of ac generator for vehicle - Google Patents

Abstract

PURPOSE:To effectively perform a damping for resonance of a pawl by disposing the contact part of a bobbin between the back of the pawl oblique part of a pole core and the outer periphery of a rotor coil, and always applying pressing force to the pawl. CONSTITUTION:When a bobbin 3, a low coil 4 and pole cores 1, 2 are engaged fixedly with knurling to a shaft 5, a pressing unit 3b is disposed between the pawl back oblique of the core 1 or 2 and the outer periphery of the coil 4, thereby always applying suitable pressing force to the pawl. A plurality of pressing parts 3a integrally formed with part of the bobbin 3 are arbitrarily provided at the same positions as the pawl of the core 2 having a plurality of poles.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotor of a vehicle alternator, particularly to a ball core claw resonance noise reduction structure.

Demand for noise reduction for automotive alternators (alternators) that use Ransol-type ball cores has been increasing year by year, and attempts to increase speed in order to improve efficiency have resulted in a dramatic increase in noise. Among them, the resonance sound of the ball core claw is a problem, and there is an urgent need to find a way to suppress and eliminate this claw resonance. The vibration mode of the pawl is a mode in which the overhang tip of the pawl vibrates in the radial direction, as shown in FIG.

An object of the present invention is to obtain a structure that can eliminate the resonance of the claw portion of the ball core.

One embodiment of the present invention has a bobbin 3 made of nylon or the like that is integrally molded with a plurality of pressing portions 3a, which are arbitrarily provided at the same positions as the claws of a ball core 2 having a plurality of poles. is,
Its shape is such that the inclination 2a of the claw back of the ball core 2 and the inclination 3b of the pressing part are almost the same, and the distance between the outer peripheral surface of the rotor coil 4 and the claw back of the ball core 2 in FIG. The distance Ll in FIG. 2 is made larger than the distance L2. In addition, 3G is partially thinned to make it easier to bend, and 3D
is a cutout for air ventilation for cooling the rotor coil 4 in the circumferential direction and for escape during compression. Further, the same applies to the ball core 1 side.

As a result, when the bobbin 3, rotor coil 4, and ball core 1.2 are knurled and fixed on the shaft 5 as shown in FIG. Since the pressing part 3a is located between the two and constantly pressing the claw part to provide a pressing part, resonance of the claw can be effectively damped.

In addition, since the pressing part 3a is integrally molded with the bobbin 3, there is no need to increase the number of parts, and the pressing part 3 does not have any adverse effects when winding the rotor coil 4, so special modification of the equipment is required. I don't. Furthermore, the cooling of the rotor coil is not impaired by the notch 3d, and the output performance is not adversely affected.

This will be explained in more detail below. As shown in FIG. 2, a plurality of pressing portions 3a integrally formed with a portion of a bobbin 3 made of nylon or the like are arbitrarily provided at the same positions as claws of a ball core 2 having a plurality of poles. Its shape is such that the slope 2a of the claw back of the ball core 2 and the slope 3b of the bobbin pressing part are almost the same, and the outer peripheral surface of the low coil 4 and the ball core 2 are approximately the same.
The width L of the pressing part is larger than the distance L2 between the back of the nail (Fig. 3).
Increase I. Note that 3c is partially thinned to facilitate bending, and 3d is rotor coil 4.
This is a cutout for cooling air in the circumferential direction and for escape during compression by the ball core. Note that this 3D shape may not be the shape shown in the figure if the target is fully satisfied.

The same applies to the ball core 1 side. after that,
The ball core 1.2 is assembled together with the coil 4 wound around the bobbin 3 formed in the shape described above, and is knurled and fixed onto the shaft 5.

Note that 5 is a shaft and 6 is a slip ring.

As described above, in the present invention, the pressing part 3a of the bobbin is located between the inclined part of the claw back of the ball core and the outer peripheral surface of the rotor coil 4, and the pressing part 3a of the bobbin is always pressed against the claw part to apply an appropriate pressing force. This has the effect of effectively damping the resonance of the claw.

Further, since the pressing part 3a is integrally molded with the bobbin 3, the number of parts does not increase, and since the pressing part 3a is foldable when winding the rotor coil 4, there is no adverse effect. Therefore, there is an advantage that no special modification of the winding equipment is required.

[Brief explanation of drawings]

Figure 1 is a schematic diagram explaining the resonance mode of a conventional generator, Figure 2 is a partial cross-sectional view of a bobbin used in an embodiment of the generator of the present invention, and Figure 3 shows the bobbin in Figure 1 installed. FIG. 4 is a partial sectional view of the rotor portion shown in FIG. 1.2...Ball core, 3...Bobbin, 4...Excitation coil, 3a...Press portion. Representative Patent Attorney Takashi Okabe

Claims (1)

[Claims] A pair of alternately interlocking Ransol-type ball cores (1,
2) and a tahohin (3) provided inside the ball air.
between the excitation coil (4) wound around the ball core, a plurality of pressing parts (
3a), and the pressing portion (3a) is attached to the bobbin (
3) A rotor for a vehicle alternator, characterized in that it is integrally molded with.