JPS6051432A - Cooling fan of rotary electric machine - Google Patents

Abstract

PURPOSE:To enable to readily and reliably secure a cooling fan by forming a cooling fan coupling slot at the side of a rotor, and disposing fixedly a fan coupler by utilizing the slot, and plastically deforming part of the rotor. CONSTITUTION:A cooling fan 2 secured to the side of a core is formed by radially forming several blades 2A by punching and bending a doughnut-shaped steel plate and perpendicularly bending the inner peripheral edge at the opposite blade side to form a stationary rib 2B. The rib is engaged fixedly with the slot 1E, its diameter coincides with that of the slot 1E, and the bending length is set equal to or larger than the depth of the slot. After the fan 2 is disposed at the side 1D of a rotor core 1, the thick rotor core contacted with the inside of the rib 2B is plastically deformed by pressing, and the rib 2B engaged with the slot 2B is coupled by tensile force and shearing force occured locally.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a cooling fan for a rotating electrical machine, and particularly to a structure suitable for fixing a cooling fan for a vehicle alternator or the like.

[Background of the invention]

Conventionally, the cooling fan fixed to the rotor core of an alternator for a tank vehicle is known from Japanese Utility Model Application Publication No. 56-54865, in which the cooling fan is mounted on the side of the rotor core and then welded. was common.

This welding method requires heavy-duty equipment, requires specialized work, and has extremely low productivity.

Furthermore, welding accuracy varies widely and it is difficult even for experienced welders to provide welding with stable joint strength.

Another method of fixing using rivets could be considered, but this also requires a large number of man-hours because it requires fastening at several locations, and as with the former method, productivity is poor.

Further, as a method for plastically bonding a cylindrical coupling member and a surface coupling member, for example, Japanese Patent Laid-Open No. 163845/1984 is known. This known example relates to the connection between the open end of a cylindrical member with a bottom and a boxwood member. After the boxwood member is fitted and arranged on the outer periphery of the cylindrical member, the outer periphery of the cylindrical member is plastically deformed by a pressing die, and the inner diameter of the flange member is preliminarily deformed. 1. Connect the two by engaging the protrusion formed in the 1. ing. Therefore, in order to increase the pulling strength, a stepped surface is provided on the joint end surface of the cylindrical member to prevent it from coming off in the axial direction. However, if the cylindrical member is thin, deformation pressure is applied during joining, and satisfactory joining accuracy cannot be obtained unless a cylindrical receiver type is used. Furthermore, when a cylindrical member is vertically connected to a cylindrical body, the use of a cylindrical receiver type is disadvantageous in terms of production and is practically impossible.

Furthermore, a method of butting a cylindrical member against a flat member and joining them by plastic deformation of metal is disclosed in Japanese Patent Application Laid-Open No. 54-150761.
It is already known from the publication no. In this joining method, a groove wider than the plate thickness of the cylindrical member is formed in advance at the abutting part of the planar members, and an annular joining groove is provided on the inner peripheral side wall of the groove and the outer periphery of the cylindrical member. A metal member with lower deformation resistance is inserted into the part, and deformation pressure is applied locally from the vertical direction to connect and fix the two parts after plastic deformation. However, although this ridge method increases the airtight structure and provides relatively good results for the bottom cover collar of the φI, it does not necessarily require a mold to restrain the outer periphery of the bottom cover, which is disadvantageous in terms of productivity. Not only is this disadvantageous, but it is also unsuitable for connecting a cylindrical member vertically to a cylindrical body.

[Purpose of the invention]

An object of the present invention is to provide a cooling fan for a rotating electric machine that can be easily and reliably fixed.

[Summary of the invention]

The present invention forms a cooling fan coupling groove on the side surface of the rotor,
The present invention relates to a cooling fan for a rotating electrical machine that uses the coupling groove to position and fix a fan coupling part and plastically deforms a part of the rotor to couple both members with tension.

[Embodiments of the invention]

FIG. 1 is a partial cross-sectional view of the rotor core of an alternator for a tank vehicle according to an embodiment of the present invention, and FIG. 2 is an enlarged view of the main part.

In the figure, a rotor core 1 made of iron is formed by integrally molding a claw magnetic pole IA extending in the axial direction and a yoke part IB, and is generally press-formed from a columnar blank by cold forging or the like. The rotor cores formed in this way form a pair, and the rotating shaft (not shown) is inserted into the blowing hole IC, and the claw magnetic poles IA of the opposing cores are arranged alternately in the circumferential direction. They are fixed facing each other. Further, a field coil is wound around the outer periphery of the yoke portion IB with an insulating material interposed therebetween to form a rotor.

An annular coupling groove IE is formed concentrically with the center of the iron core 1 on the side surface (see FIG. 5) ID of the iron core 1 on the side opposite to the claw magnetic pole,
The depth is about 2 to 5 cuts, and it can be formed at the same time as the iron core by forging or by machine cutting. On the other hand, two cooling fans are fixed to the side of the iron core.By punching and bending a donut-shaped steel plate, several blades are formed radially, and the inner peripheral edge is bent at right angles to the opposite side of the blade and fixed. A rib 2B is formed. This fixing lip is connected to the coupling groove IE.
Since it is to be fitted and fixed in the groove, its diameter matches the diameter of the coupling groove IE, and the bending length is set to be equal to or less than the depth of the coupling groove.

Then, after placing the cooling fan 2 on the side surface ID of the rotor core 1, the thickness of the rotor core on the inside of the fixing rib 2B is plastically deformed by compression, and the fixing lip 2B fitted in the coupling groove IE is locally deformed. It is coupled by the tension force and shear force generated in

Next, the coupling process of the present invention will be explained with reference to FIGS. 3 to 5. First, the rotor core 1, which has been previously formed and has coupling grooves IE, is placed in a mold 3 with the claw magnetic poles IA facing downward. The bottom surface and the surrounding area are restrained by this mold, and the cooling fan 2 is placed on the side surface ID of the iron core, and the fixing lip 2B is fitted into the coupling groove IE. In this state, the cooling fan 2 is connected to the coupling groove IE.
It is positioned and stationary. Next, the mold 4 having the annular male tooth 4A is lowered from above to position the male tooth inside the fixed lip 2B. When the mold 4 is lowered to -, as shown in detail in Figure 2, the male teeth vertically press the core wall thickness near the coupling groove, causing local plastic deformation. The cooling fan 2 is exactly on the bottom of the mold 4.
The cooling fan is configured to press against the upper surface of the fixed rib to prevent the cooling fan from floating. Now completely male teeth 4A
When the is lowered, the iron core part pressed by the male teeth moves in the direction of the coupling groove 1E (which has a small gap between it and the fixing lip 2B).
It is plastically deformed in the direction shown by the arrow in Fig. 2 and comes into close contact with the fixing lip 2B.
They are connected with tension based on the principle of tres force (TR, ESCA) as shown in Japanese Patent Publication No. 58-12093.

The cooling fan connected in this way is extremely strong against pulling force because the entire circumference of the fixing lip is firmly connected by tension force and shear force. Also, compared to fixing with rivets or welding, it has the advantage that it can be reliably and firmly connected with simple work without the need for special equipment or structure. (In terms of mounting accuracy, the cooling fan is arranged and coupled along the coupling groove IE, so the mounting precision is improved without any special measures.

In the second embodiment, the annular coupling groove IE is formed in the rotor core 1, but this groove may be formed intermittently as long as it does not cause the unsheathing of the blade. On the other hand, if it is desired to increase the extraction force, an annular groove (unevenness) 2C is formed in the inner cylinder of the fixed lip 2B of the cooling fan, as shown in the embodiment shown in FIG. The force increases further and the bond strength increases even more.

Although the fixed lips of the cooling fan are usually harder than the stator core, they only need to have the same hardness to obtain sufficient tension, and as the hardness decreases, the bonding force decreases.

In still another embodiment, the blades of the cooling fan may be formed to face inward, and a fixed lip may be provided on the outer peripheral edge, and the fixed lip may be formed in a pre-formed annular groove. It also shows good results in rotating electric machines.

Although the above embodiments have been described with respect to an armature core of a vehicle alternator, similar effects can be obtained when a cooling fan is fixed to a rotor of an electric motor, a flywheel magneto, or the like.

〔Effect of the invention〕

According to the present invention, a cooling fan for a rotating electrical machine that can be easily and reliably fixed is provided.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention. FIG. 1 is a half-sectional view of a rotor core to which a cooling fan is fixed, FIG. 2 is an enlarged view of the main part of FIG. 1, and FIGS. 3 to 5 are Figure 3 is a cross-sectional view of the press mold, Figure 4 is a cross-sectional view of the cooling fan, Figure 5 is a cross-sectional view of the rotor core mold arrangement, and Figure 6 is another embodiment. FIG. 1...Rotor core, IE...coupling groove, 2...cooling fan, 2B...fixing lip. Agent Patent Attorney Akio Takahashi'SAt 2 Akira/E Figure 3 Akio 4

Claims (1)

[Claims] 1. A cooling fan for a rotating electric machine in which a fan is mounted and fixed on the side surface of a rotor, which includes a rotor having a coupling groove formed on the side surface concentric with the axis, and one end of the mounting surface. and a fan having a fixing part formed by vertically bending and fitting into the coupling groove,
1. A cooling fan for a rotating electrical machine, wherein the fan is fixed by plastic deformation pressure and tension generated by vertically locally pressing a part of the rotor around the coupling groove. 2. A cooling fan for an FC rotating electrical machine as set forth in claim 1, wherein the coupling groove is an annular all-circumferential groove. 3. A cooling fan for a rotating electric machine as set forth in claim 1, wherein the coupling portion of the fan has an uneven portion on its coupling surface.