JPS5839250A - Connecting method for rotor core to rotary shaft - Google Patents

Abstract

PURPOSE:To eliminate the lowering of a pressing force even when these is an error in the machining precision of a laminated iron core, by putting the laminated iron core on a knurled rotary shaft, and by caulking later the part of this laminated iron core which is adjacent to the rotary shaft, while applying a pressure thereto. CONSTITUTION:After knurling 2a is applied to the peripheral surface of a rotary shaft 2, a laminated iron core 3 is fitted to the knurled part of the shaft. Then, the part of the core 3 which is adjacent to the rotary shaft 2 is caulked under a pressure given by pressing dies 6a and 6b, and thereby the inside-diameter part of the laminated iron core 3 is fully thrusted into a knurled part 2a.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a connection method for fixing a rotor core to a rotating shaft in a rotating electrical machine, particularly in a rotating electrical machine such as a DC motor for starting an automobile engine.

FIG. 1 is a diagram explaining the conventional method, in which (a) is a partially cross-sectional side curved view, and (b) is an IF line AA in (a).
A cross-sectional view taken along a plane perpendicular to the rotation axis, including
is an enlarged view of the vicinity indicated by B in FIG. In these figures, fil comprehensively represents the rotating shaft (2) and the laminated core (31) fitted thereto, and the product 1 - the length of the core is tc
(2a) is the knur of the rotating shaft (2).
t) Processed surface, (4) Knurled surface (
This is a gap formed between the inner circumferential surface of the laminated core (31) inserted into 2a). A rotor winding (not shown) is disposed in this +51 V'i slot.

Since the overall structure of a DC motor is well known, the explanation will be omitted, but in Fig. 1, the load on the motor (rotating shaft of the engine to be started) is 6%. This refers to Figure 1tsE of Figure 1 (Figure 1). same as below.

), this 11 (when the motive is operated, torsional strain is generated between the right and left sides of the rotating shaft (2) 41
I'll do it. This screw! The core (2a) is attached to the knurled surface (2a) to prevent the laminated core (31) from being pulled out from the rotating shaft (21 and slippage occurs between the two).
It would be great if both could be fitted together by marking 11 in 3). For example, a normal starting electric motor of about 2 kW can withstand an extraction pressure of about 1.5 tons, which is required.

However, since the conventional device is manufactured by the method described above, the biting state of the core (31) on the knurled surface (2a) differs depending on the machining accuracy error of - laminated core + 31, and this error This has the disadvantage of producing products with reduced evacuation pressure.

This invention was developed to eliminate the above-mentioned drawbacks of the conventional method, and even if there are variations in dimensions due to processing accuracy of the laminated core, the rotating shaft and the laminated core can be firmly and reliably fitted. The purpose is to provide possible connection methods.

Embodiments of the present invention will be described below with reference to the drawings. end'
FIG. 2 is a partial side sectional view showing an embodiment of the present invention, in which the same reference numerals as in FIG. After fitting the 4IJ layered iron core (31) to the rotating shaft (2), the surface of the rotating shaft (2) is knurled in the same manner as in case 1 in Fig. 1, and then the suppression mold (6a), One in (f; h) - (part 4 near the outer periphery of the rotating shaft (2) on both sides of the laminated core (3))
is pressed with the force F shown in Fig. 2 to apply caulking.
ing). With this caulking, the laminated iron core (co(
) is slightly thicker than the outer diameter of the rotating shaft (2), even if the inner circumferential surface of the laminated core (3) is the same as the surface (2a) with the 2+11 milled surface. Enough biting improves extraction pressure reliability. That is, the void portion (4) shown in FIG. 1(c) is filled by the inward deformation of the 4tt layer iron core (31), and a decrease in contact pressure due to processing accuracy errors is prevented.

Figure 3 does not show other embodiments of the present invention, and Figure 3 (a) is a partial side sectional view, Figure 3 (1)) tit =
, A. In Figure 3 (a), straight line CCf: In the plane perpendicular to the axis of rotation (14 shows a cross-sectional view. In Figure 3, the same ministry name as Figure 2 indicates the same or equivalent part, ( 7) is the hydraulic brake
A plurality of tapered protrusions (7a) arranged in the shaded area in FIG.
Therefore, it is possible to easily caulk the portion shown in "2.I.", and it is possible to improve the extraction force between the rotating single shaft (2) and the laminated iron core (3).

Furthermore, the knurled surface (2a) of the rotary tlQl+ +21 may be subjected to a suitable surface treatment ITI, for example, a phosphoric acid coating treatment, thereby preventing the vortex J, 17 generated by the magnetic flux change within the rotating shaft. ．． The secondary effect is that the flow is blocked by the phosphoric acid coating on the fitting surface and the magnetic stability is improved. It is possible to prevent burn-in due to

As described in 2 below, according to the present invention, after the laminated core is fitted into the knurled rotation 1η11, both sides of the laminated core are caulked continuously or intermittently using a pressing die such as a hydraulic press. This prevents a drop in ejection pressure and makes it possible to obtain a highly reliable product.In addition, by applying a non-conducting coating such as a phosphoric acid coating to the knurled surface of the rotating shaft, it is possible to prevent fitting. Part vortex tli flow loss prevention market can be done, low workability Fittj child 4 specialized cuff large T14 and (j (can be done).

[Brief explanation of drawings]

Fig. 1 is a drawing showing one embodiment of the conventional method, Fig. 2 is a drawing showing one embodiment of the present invention, and Figs. 1 and 3 are drawings showing other embodiments of the invention. (2)...Rotating shaft, (3)...Laminated iron core, ((ja
, ), (rib), i71...pressing mold for hydraulic press. In addition, the same reference numerals in the drawings indicate the same or L [corresponding parts. Agent Shin Kuzuno −

Claims (2)

[Claims] (1) Knurl on the surface of the rotating shaft of a rotating electric machine
a step of applying the knurled rotating shaft to a laminated core constituting the rotor core of the rotating electrical machine; and a step of fitting the laminated core that is fitted to the rotating shaft into the rotating shaft A method for connecting a rotor core and a rotating shaft, the method comprising the step of pressing a close portion by press working and caulking the laminated core. (2) Claim O1 characterized in that the process of applying knurl processing includes the process of applying phosphoric acid film treatment to the rotating shaft.
How to connect the rotor core and rotating shaft as described in .