JPS6248472B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotor for a magnet generator, and particularly to a caulking structure of a boss portion thereof.

The rotor of a magnet generator attached to the crankshaft of an automobile engine generally includes a cylindrical portion (boss) made of a relatively hard material so as to be inserted through and attached to the crankshaft, and fixed to the boss. It consists of a bowl-shaped yoke to which a magnet or the like is attached, and these bosses and the yoke are usually fixed by ``caulking''.

In the conventional boss portion caulking structure, as shown in FIGS. 1A and 1B, the yoke 12 is fixed to the boss 11 by caulking using a plurality of rivets 13.

By the way, in such a system, the fixing strength between the yoke and the boss is ensured by the caulking portion of each rivet. That is, in this method, in FIG. 1A, the hole 11a of the boss 11 and the corresponding hole 12a provided in the yoke 12 are
The rivet 13 is inserted through and caulked. In this case, the caulked part 13a of the rivet 13 formed in the shape of a brim is pressed against the yoke 12 and the boss 11, and this press-contact force causes the boss 1 to be caulked.
1 and yoke 12 are pressed and fixed. At the same time, since the shaft portion 13b of the rivet 13 is inserted through both the holes 11a and 12a, the boss 11 and the yoke 12 are fixed in their rotational direction. In this way, when fixing by caulking with a rivet, the axial direction of the rivet is fixed by the flange formed by caulking the rivet, and
Fixation in the rotational direction is achieved by engagement of the shaft portion of the rivet, so that when the boss 11 is fixed to a rotational drive shaft such as a crankshaft of an automobile engine and rotated, the yoke 12 is fixed to the boss 11. They are fixedly held on the boss 11 so as to rotate as one.

However, in this type of caulking fixation using rivets, the point of application of the fixing force is limited to only the caulked part of the rivet as described above, and from the perspective of fixing the boss and yoke, one of these two members is It simply applies a bonding force to the points. Moreover, in this case, the fixation between the boss and the yoke is required to withstand severe impact forces repeatedly applied as the engine rapidly accelerates and decelerates for many years. Therefore, in order to withstand such harsh conditions, it is necessary to use a large number of rivets and to increase the number of points of action as much as possible. Furthermore, in order to use a large number of rivets, it is necessary to increase the diameter of the flange portion of the boss (diameter A) in FIG. 1A to secure a place for attaching the rivets. As described above, in the caulking method using rivets, the flange portion of the boss must be made large and a large number of rivets must be used.

However, the rivet caulking method is
Generally, it is weak against torsional torque, so even if a large number of rivets are used, it may be able to withstand normal impact force, but it will not be able to withstand unexpected excessive impact force or repeated stress over many years. It could not necessarily be said that they would be able to withstand this situation with a degree of leeway; in fact, they could not shake off the fear that the rivets would become loose. Furthermore, from a manufacturing standpoint, the boss is usually manufactured by forging in order to obtain the required hardness, but if the diameter A of the flange is large, the casting operation becomes extremely difficult. Furthermore, there are many disadvantages in terms of manufacturing cost and production control because the number of parts and manufacturing steps are large, such as the need to drill common holes in the boss and yoke in order to attach a large number of rivets.

An object of the present invention is to eliminate the above-mentioned drawbacks, and to provide a fixing structure between a boss and a yoke that can withstand excessive impact force and repeated stress over many years with sufficient margin. It is an object of the present invention to obtain a rotor for a magnet generator, which has a small number of parts, is easy to manufacture each part, and has a small assembly manufacturing process, which is extremely advantageous in terms of manufacturing cost and production control.

To achieve this object, the present invention provides a rotor for a magnet generator in which a boss is attached to a bowl-shaped yoke so that the axis of rotation of the yoke is common to that of the yoke, wherein the boss is formed by forging and has a cylindrical shape. a cylindrical portion, and a radial entire circumference extending from one end of the cylindrical portion to the cylindrical portion and having a diameter slightly larger than the outer diameter of the cylindrical portion along a plane perpendicular to the axis of the boss. The base of the cylindrical portion that connects the cylindrical portion to the flange portion has an outer circumferential surface formed in a curved shape with a substantially arcuate cross section; A serration portion is formed in a region extending from near the axial center of the outer peripheral surface of the cylindrical portion to the base of the cylindrical portion, and the bowl-shaped yoke includes a disc-shaped bottom portion and a bottom surface a cylindrical side wall section extending continuously from the outer periphery of the section in a direction perpendicular to the bottom section; a cylindrical part that is bent and extended, has an inner diameter slightly smaller than the outer diameter of the cylindrical part of the boss, and shares an axis with the side wall part; The base of the cylindrical part connected to the cylindrical part is formed in a curved shape having a substantially arcuate cross section corresponding to the curved outer peripheral surface of the base of the cylindrical part of the boss, and the bottom surface near the base of the cylindrical part is connected to the cylindrical part. The boss is formed on a surface substantially perpendicular to the axial direction of the cylindrical part, and a serration part is provided at a portion extending from one end in the axial direction of the inner circumferential surface of the cylindrical part to the base part, and the boss is The serration portions of the boss and the yoke are press-fitted into the cylindrical portion of the yoke so that they engage with each other and the curved portions of the boss and the yoke are in contact with each other, and the side opposite to the flange portion of the boss is press-fitted into the cylindrical portion of the yoke. The boss is fixed to the yoke by caulking the entire circumference of the end in the direction toward the flange part and forming a caulking part, whereby the boss and the yoke are firmly attached to each other in an extremely tight state. A combination is made.

FIG. 2 is a sectional view showing a rotor of a magnet generator according to an embodiment of the present invention, and FIGS. 3A and 3B are sectional views of each component of the rotor shown in FIG. 2.

In the figure (see especially FIG. 3B), reference numeral 1 indicates a boss, and this boss 1 has a generally cylindrical shape as a whole, and is connected to a cylindrical portion 1a and the cylindrical portion. It consists of a flange portion 1b extending outward from one end over the entire circumference in the radial direction along a plane perpendicular to the axis of the boss so as to have a diameter slightly larger than the outer diameter of the cylindrical portion. A tapered hole 1c into which a crankshaft (not shown) is fitted is formed in the cylindrical portion 1a, and a keyway 1d is provided in the tapered hole 1c.

Further, the outer peripheral surface of the base part 1f of the cylindrical part 1a connected from the cylindrical part 1a to the flange part 1b is formed in a curved shape having a substantially arcuate cross section, and further, the outer peripheral surface of the cylindrical part 1a of the boss 1 The boss 1 is located at a portion extending from the vicinity of the axially central portion to the base 1f of the cylindrical portion 1a (a portion corresponding to the yoke cylindrical portion to be described later).
An involute serration part 1e is formed by alternately providing a large number of peaks and valleys in the circumferential direction, the longitudinal direction of which is formed along the axial direction on the entire outer circumference of the substantially central part in the axial direction. It is formed.

In addition, in the figure (see especially Figure 3A), the reference numeral 2
is a yoke, and this yoke 2 has a generally bowl-shaped overall shape, and extends continuously from the outer periphery of the bottom surface portion 2a and in a direction perpendicular to the bottom surface portion 2a, It consists of a cylindrical side wall part 2b having a common axis with the bottom part 2a, and the side wall part 2b is bent and extended in a right angle direction toward the inside of the yoke 2 at the center part of the bottom part 2a. A cylindrical portion 2c having a common axis with 2b is formed.
Further, on the inner circumferential surface of this cylindrical portion, a serration portion 1e corresponding to the serration portion 1e of the boss 1 is provided.
Serration portion 2d that can be engaged and fitted
Further, the portion where the serration portion 2d and the bottom portion 2a connect, that is, the inner circumferential surface of the base portion 2e of the cylindrical portion 2c has a curved section having a substantially arcuate cross section corresponding to the base portion 1f of the boss 1. is formed. And, on the inner peripheral surface of this cylindrical part 2c,
As shown in FIG. 2, the boss 1 is press-fitted and fixed by caulking.

That is, the boss 1 is connected to the yoke such that the serration portion 1e on the outer peripheral surface of the boss 1 engages with the serration portion 2d of the yoke 2, and the flange portion 1b of the boss 1 is in contact with the bottom surface 2a of the yoke 2. After that, one end of the boss 1, that is, the entire circumference of the part near the outer circumferential side of the left end in the figure, is crimped, and the dotted line part in the figure is deformed to form the crimped part. 1
As is clear from the figure, the cylindrical portion 2c of the yoke 2 is firmly held between the flange portion 1b of the boss 1 and the caulked portion 1g. Note that the yoke 2 can be relatively easily obtained by press molding.

The effects of the present invention embodied in the embodiments detailed above are as follows.

That is, the base part 1f of the boss 1 and the base part 2e of the yoke 2 are both formed into curved shapes, and the bottom surface near the base of the cylindrical part is in a plane substantially perpendicular to the axial direction of the cylindrical part. As a result, the force acting on both of them at the time of caulking acts uniformly over each part of both, and as a result, from the inner circumferential surface of the cylindrical portion 2c of the yoke 2 to the outer circumference of the bottom surface portion 2a. The entire surface is pressed and fixed to the outer peripheral surface of the boss 1 in a very close contact state. Moreover,
As a very common-sense action in the "caulking" process, when the caulking part 1g is formed on the boss 1, the right cylindrical part 1a of the caulking part 1g in FIG. 2 bulges outward slightly. , the serration portion 1c of the boss 1 and the serration portion 2d of the yoke 2 are more firmly engaged and are almost crimped. If we look at this point from the perspective of fixing the connection between two members, generally speaking, the more points there are at which the bonding force that connects the two members acts, the stronger the connection will be. First, the convex portion and the concave portion of both serration portions are engaged with each other by press-fitting, and the bonding force due to the press-fitting is applied over the entire surface area of these concavo-convex portions. next,
The cylindrical portion 2c of the yoke 2 is formed by the caulking process.
The boss 1 extends from the inner circumferential surface of the boss 1 through the curved base 2e to the bottom surface 2a, and the surface that abuts the caulked portion 1g of the cylindrical portion 2c. A bonding force due to ``caulking'' acts between each of these surfaces and the abutting surfaces. In addition, as described above, due to the "caulking", a stronger bonding force acts on the serrations.

In this way, the area on which the bonding force acts is not a point but a plane, and since the acting surface is not just a plane but acts as a concave part and a convex part interlock, the acting area itself is a plane. The force is extremely large compared to , and the force acts in various directions. Therefore, the two are extremely firmly fixed not only in the direction of rotation of the boss 1 but also in all directions, creating a connection that is incomparably stronger than the conventional caulking fixation method using rivets. .

Therefore, it goes without saying that it can withstand, with sufficient margin, the severe impact force that is repeatedly applied over many years due to rapid acceleration and deceleration of the engine, and it can also withstand unexpected excessive impact forces. This makes it possible to withstand even when impact force is applied.

Furthermore, since the boss 1 and the yoke 2 are connected to each other at the portion extending from the serration portion 1e to the flange portion 1b of the boss 1, it is not necessary to increase the diameter of the flange portion of the boss as in the conventional caulking method using rivets. In addition, the base 1 of the flange portion 1b
Since f is shaped like an arc, mass production by forging of this boss 1 is extremely easy. In other words, if the diameter of the flange part were to be increased as in the past, and the base part 1f had to be formed not in a curved shape but in a substantially right-angled cross-section, forging would become extremely difficult, and in fact it would be impossible to forge. Mass production becomes impossible.

Similarly, since the base portion 2e of the cylindrical portion 2c of the yoke 2 has an arcuate curved shape, mass production of the yoke 2 by pressing is extremely easy. If this is formed into a substantially right-angled cross section,
Due to the strength of the bent portion, mass production by pressing is virtually impossible.

Furthermore, the number of parts is only the yoke and boss,
In addition, since the assembly process involves simply press-fitting the boss into the yoke and caulking it, the number of parts and the assembly process are extremely small compared to the conventional method.

As described above, the present invention brings about extremely significant effects in terms of production costs and production management, especially when highly reliable parts such as automobile parts must be supplied quickly and in large quantities at low cost. be.

[Brief explanation of the drawing]

1A and B are a partial sectional view and a partial front view showing a conventional example, respectively. FIG. 2 is a sectional view showing an embodiment of the present invention. FIGS. 3 A and B are a boss 1 in FIG. 2, respectively. FIG. 2 is a cross-sectional view showing the state of the yoke 2 before assembly. 1... Boss, 1e... Involute serration part, 1b... Flange part, 1f... Base of flange part, 1g... Caulking part, 2... Yoke, 2
a...Bottom part, 2b...Side wall part, 2c...Cylindrical part, 2d...Serration part, 2e...Base part.

Claims (1)

[Scope of Claims] 1. A rotor for a magnet generator in which a boss is attached to a bowl-shaped yoke so that the axis of rotation of the yoke is common to that of the yoke, wherein the boss is formed by forging and has a cylindrical portion. , connected to the cylindrical part and extending from one end of the cylindrical part to the entire circumference in the radial direction along a plane perpendicular to the axis of the boss so as to have a diameter slightly larger than the outer diameter of the cylindrical part. a flange portion extending outward; the base of the cylindrical portion connecting from the cylindrical portion to the flange portion has an outer circumferential surface formed in a curved shape having a substantially arcuate cross section; and a cylindrical portion of the boss; A serration portion is formed in a portion extending from approximately the center in the axial direction of the outer peripheral surface to the base of the cylindrical portion, and the bowl-shaped yoke includes a disc-shaped bottom portion and a portion extending from the outer periphery of the bottom portion. a cylindrical side wall portion extending continuously in a direction perpendicular to the bottom surface portion; and a side wall portion formed in a cylindrical shape and extending in a direction perpendicular to the bottom surface portion; A cylindrical part that is extended and has an inner diameter slightly smaller than the outer diameter of the cylindrical part of the boss and shares an axis with the side wall part, and is bent from the bottom part and connected to the cylindrical part. The base of the boss is formed in a curved shape with a substantially arc-shaped cross section corresponding to the curved outer peripheral surface of the base of the cylindrical portion of the boss, and the bottom surface near the base of the cylindrical portion is parallel to the axial direction of the cylindrical portion. The serration portion is formed on a substantially perpendicular surface, and is further provided with a serration portion at a portion extending from one end in the axial direction of the inner circumferential surface of the cylindrical portion to the base portion, and the serration portion is formed on a surface extending substantially perpendicularly to the cylindrical portion of the yoke. The boss and the yoke are press-fitted into the shaped portion so that the serration portions of the boss and the yoke engage with each other and the curved portions of the boss and the yoke are in contact with each other, and further, the entire end of the boss opposite to the flange portion is pressed into the shaped portion. A rotor for a magnet generator, characterized in that the boss is fixed to a yoke by caulking the circumference in a direction toward the flange portion to form a caulked portion.