JPH025652Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a flywheel magnet rotor that constitutes the rotor of a magnet generator, and is particularly suitable for use in a magnet generator attached to an internal combustion engine. be.

[Conventional technology]

As a flywheel magnet rotor used in a magnet generator attached to an internal combustion engine, there is one in which a magnet is attached to a flywheel manufactured by drawing. Flywheels manufactured by drawing in this way are light in weight and have a small moment of inertia, so if a large flywheel effect is required, a weight for increasing the moment of inertia is attached to the flywheel using fasteners made of screws or rivets. things are being done. Since a fairly thick weight is used to increase the moment of inertia, if the insertion hole of the fastener is made to have the same diameter throughout the thickness of the weight, a long fastener will be required. It is unavoidable that the degree of adhesion between the fastener and the inner surface of the hole through which the fastener is inserted deteriorates, resulting in a decrease in installation strength. Therefore, conventionally, a circular enlarged diameter part that shares an axis with the insertion hole is formed at the opening of the insertion hole provided in the weight for inserting the fastener, and the enlarged diameter part is converted into a recess for accommodating the head of the fastener. year,
by receiving the head of the fastener within the recess;
It was possible to use fasteners with short lengths.

[The problem that the idea aims to solve]

However, in order to form a fastener insertion hole that has an enlarged diameter portion in the opening, a guide hole for a countersunk cutter is first provided at the position where the insertion hole is to be provided, and then counterbore cutting is performed to enlarge the diameter. Since the insertion holes must be drilled after forming the parts, the number of man-hours increases and manufacturing efficiency is reduced.

An object of the present invention is to provide a flywheel magnet rotor to which a weight for increasing the moment of inertia can be firmly attached without performing troublesome machining such as counterbore cutting.

[Means to solve the problem]

The present invention consists of a flywheel formed into a substantially cup shape, a permanent magnet attached to the inner periphery of the flywheel, and a fastener arranged concentrically with the flywheel and fixed to the flywheel by a fastener made of screws or rivets. and a weight for increasing the moment of inertia, and the fastener is fastened in a recess for accommodating the fastener head, which is formed continuously with the open end of the insertion hole, which is provided by passing the weight through the fastener. The target is a flywheel magnet rotor in which the head of the tool is housed.

In the present invention, the recess for accommodating the fastener head comprises a groove provided around the weight for increasing the moment of inertia so as to extend concentrically with the flywheel, and the fastener insertion hole is provided inside the groove. It's open.

[Effect]

When forming a fastener insertion hole with an enlarged diameter part in the opening, first drill a pilot hole for guiding a countersunk cutter at the position where the insertion hole is to be provided, and then perform counterboring cutting to form the enlarged diameter part. However, after that, it is necessary to make an insertion hole with a drill.

On the other hand, if the recess for accommodating the fastener head is formed by a groove provided around the weight for increasing the moment of inertia so as to extend concentrically with the flywheel as in the present invention, the step of providing the groove around the , the step of drilling an insertion hole inside the groove,
Moreover, since the circumferential groove can be easily formed by lathe machining, machining of the weight for increasing the moment of inertia can be facilitated.

Embodiments of the flywheel magnet rotor of the present invention will be described below with reference to the drawings.

Embodiment (1) Figures 1 and 2 show a first embodiment of the present invention. In these figures, 1 is a flywheel formed into a substantially cup shape by drawing an iron plate. A permanent magnet 2 is attached to the inner peripheral surface of the peripheral wall portion 1a of the flywheel 1. A plurality of permanent magnets 2 may be formed in an arc shape and may be mounted at intervals in the circumferential direction, or a plurality of arc-shaped magnets may be arranged and mounted in a ring shape. Furthermore, a ring-shaped integral magnet may be fitted onto the inner periphery of the flywheel 1. In any case, the magnet 2 is magnetized so that its magnetic poles are arranged in a predetermined order in the circumferential direction of the flywheel, and these magnetic poles face the magnetic poles of a stator (not shown) via a gap. In FIG. 1, reference numeral 1b is a protruding portion formed by protruding a part of the peripheral wall portion 1a radially inward in order to position the magnet 2 in the axial direction of the flywheel.

A boss fitting hole 1d is formed in the center of the bottom wall portion 1c of the flywheel 1, and a boss 3 for attaching a rotating shaft is fitted into this hole 1d. A disk-shaped moment of inertia increasing weight 4 is integrally formed at the end of the boss 3 located outside the flywheel 1, and this weight 4 is in contact with the outer surface of the bottom wall portion 1c of the flywheel. A disc-shaped weight 4 is provided concentrically with the flywheel 1, and a groove 4a extending concentrically with the flywheel is formed around its outer end surface by lathe processing. The inside of this groove 4a serves as a recess for accommodating the head of the fastener. A fastener insertion hole 4b that penetrates the weight 4 at the inner part of the groove 4a.
A plurality of through holes 1e are provided at equal intervals in the circumferential direction, and the bottom wall portion 1c of the flywheel 1 is provided with a through hole 1e that is aligned with the through hole 4b. A fastener 5 is inserted into each fastener insertion hole 4b and through hole 1e, and the weight 4 is coupled to the flywheel 1 by this fastener. The length of each fastener 5 is set to be sufficiently short so as not to reduce the mounting strength of the weight 4, and the groove 4a constituting the recess for accommodating the fastener head has the length of the fastener insertion hole 4b smaller than the length of the fastener 5. The depth is suitable for setting the length commensurate with the
It has a width sufficient to accommodate the head 5a of the fastener 5. In the illustrated example, rivets are used as the fasteners 5, and their respective tips are caulked against the inner surface of the bottom wall portion 1c of the flywheel. The boss 3 has a tapered hole 3a into which a tapered portion provided at the tip of a rotating shaft, for example, an output shaft of an internal combustion engine, is fitted.

Embodiment (2) FIG. 3 shows a second embodiment of the present invention, in which a ring-shaped weight 6 for increasing the moment of inertia is fitted around the outer periphery of the flywheel 1. A groove 6a extending concentrically with the flywheel is provided on the outer periphery of the weight 6, and a fastener insertion hole 6b is formed so as to penetrate the weight 6 inside the groove 6a. In this example, the groove 6a
The inner side is a recess for accommodating the fastener head. Further, a screw is provided as the fastener 5, and this screw is screwed into a screw hole 1f provided in the flywheel 1 through the insertion hole 6b. Head 5 of fastener 5
This embodiment is similar to the first embodiment in that the groove 6a is fitted into the groove 6a. The boss 3 integrally has a flange portion 3b at the end located outside the flywheel 1, and this flange portion is attached to the flywheel 1 by a rivet 7.
is combined with

Embodiment (3) FIG. 4 shows a third embodiment of the present invention. In this example, a ring-shaped moment of inertia is installed to surround the flange 3b of the boss attached in the same way as in FIG. 3 from the outside. An increasing weight 8 is arranged. An enlarged diameter portion 8a is formed at one end of the inner circumference of the weight 8, and the flange 3b of the boss 3 is fitted into this enlarged diameter portion 8a. By performing lathe processing on the outer end surface of the weight 8, an annular recess 8b concentric with the flywheel 1 is formed, and a groove 8c extending concentrically with the flywheel 1 is provided around the bottom of this recess. . The inside of the groove 8c is a recess for accommodating the head of the fastener, and a fastener insertion hole 8d is formed inside the groove 8c, and a through hole aligned with the insertion hole 8d is formed in the bottom wall of the flywheel 1. 1g is formed. And each insertion hole 8d and through hole 1g
A rivet as a fastener 5 is inserted into the flywheel 1, and the weight 8 is fixed to the flywheel 1 by caulking the rivet to the flywheel 1.

[Effect of idea]

As described above, according to the present invention, a groove extending concentrically with the flywheel is provided around the weight for increasing the moment of inertia, this groove is used as a recess for accommodating the head of a fastener, and the fastener is placed inside the groove. Since the insertion hole is opened, the recess for accommodating the fastener head can be formed by simple lathe processing without counterboring, which increases the number of man-hours. This has the advantage of reducing costs by reducing man-hours.

[Brief explanation of the drawing]

1 and 2 are a vertical sectional view and a front view showing a first embodiment of the present invention, respectively, FIG. 3 is a half vertical sectional view showing a second embodiment of the present invention, and FIG. FIG. 3 is a vertical cross-sectional view showing a third embodiment of the present invention. 1...Flywheel, 2...Permanent magnet, 3...
...Boss, 4, 6, 8... Weight for increasing moment of inertia, 4a, 6a, 8c... Groove for fitting the fastener head provided around the weight, 5... Fastener.

Claims (1)

[Claims for Utility Model Registration] A flywheel formed into a substantially cup shape, a permanent magnet attached to the inner periphery of the flywheel, and a screw or rivet arranged concentrically with the flywheel. a weight for increasing the moment of inertia fixed by a fastener consisting of a fastener; in the flywheel magnet rotor, wherein the fastener head is accommodated in the recess, the fastener head receiving recess extending concentrically with the flywheel to reduce the inertia. A flywheel magnet rotor comprising a groove circumferentially provided in a moment increasing weight, wherein the insertion hole is opened inside the groove.