JPS6048992B2 - Manufacturing method of electromagnetic induction coupling device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing an electromagnetic induction coupling device, and more particularly to an improvement in a means for fixing a conductive material and a magnetic material constituting a second rotating main body.

Hereinafter, a conventional device will be explained with reference to FIGS. 1 to 8.
In the figure, 1 has a plurality of grooves arranged at predetermined intervals on the inner circumference, an annular iron part 1a with low magnetic resistance, and an aluminum part 2 as a conductor provided in these grooves. A second connecting body consisting of an aluminum portion 2a that short-circuits these aluminum portions 2 in a cage shape, 2b has an aluminum portion 2 on the outer peripheral surface of the driver 1;
A heat sink is provided integrally with 2a to improve heat dissipation, and is made by casting and solidifying molten aluminum.

3 is a pulley fixed to the drive body 1 with a bolt (not shown); 4 is a driven body which is a first connecting body and is composed of a large number of magnetic poles so as to alternately form different poles in the circumferential direction;
Reference numeral 5 denotes an excitation coil disposed within the driven body 4, and 6 a hollow load shaft fixed to the driven body 4, which rotatably supports the pulley 3 via a bearing 7.

8 is a holding device for the brush 9, which holds the brush 9 through a bearing 10;
It is rotatably supported on the load shaft 6.

11 is a slip ring electrically connected to the excitation coil 5.

Next, the operation of this conventional device will be explained.

First, when the excitation coil 5 is excited from a DC power source (not shown) via a current collector consisting of a brush 9 and a slip ring 11, a magnetic flux Φ as shown by the dotted line is generated. Here, when the pulley 3 is driven by a drive source such as a motor (not shown) via a belt (not shown), the driving body 1 fixed to the pulley 3 starts rotating at a predetermined speed. The iron portion 1a on the inner circumference of the driving body 1 receives an alternating magnetic field in which the direction of the magnetic flux Φ changes over time, and is therefore disposed on the inner circumference with a predetermined gap from the magnetic pole surface of the driven body 4. An induced voltage is generated in the iron portion 1a due to the relative speed between the driven body 4 and the driving body 1. This induced voltage causes the aluminum part 2 as a conductor to
, 2a generates a secondary current based on its resistance value, and this secondary current
An attractive force is generated between the driving body 1 and the driven body 4 due to the interaction between the magnetomotive force generated by the next current and the magnetomotive force based on the magnetic flux Φ generated by the excitation coil 5. Therefore, torque is electromagnetically transmitted from the driving body 1 to the driven body 4, and the load is driven by the driving source. Now, the iron part 1a and the aluminum part 2, which constitute the second connection main body,
Fixation with 2a is performed as follows.

First, in order to cast aluminum parts 2, 2a as conductors into an annular iron part 1a, holes 1c are formed at predetermined intervals in the circumferential direction as shown in FIG. 4 using a multi-spindle drilling machine.

When performing this hole machining, it is necessary to provide an extra iron portion 1b inside the iron portion 1a actually required for forming the driving body 1. This is because, without this extra thickness, the drill for drilling the hole would escape inward and the hole 1c could not be drilled. Moreover, the molten aluminum is inserted into the hole 1c of the iron part 1a as a conductor. In order to cast the miniumized parts 2, 2a, this extra iron part 1b must be removed by cutting beforehand. Therefore, the yield rate of the iron raw material is poor, and the iron part 1b is cut intermittently, resulting in poor workability, resulting in a shortened tool life, and furthermore, there is less burr after cutting.
There are many disadvantages from the viewpoint of resource and energy saving as it requires reclamation. The present invention provides an excellent method for manufacturing an electromagnetic induction coupling device which eliminates the above-mentioned drawbacks by forming concave grooves at predetermined intervals in a magnetic material by cutting without drilling.

The embodiment shown in FIG. 5 will be described below.

That is, the radial thickness of the annular iron portion 1a (7) is processed to the actually required thickness, and the inner circumferential side of the iron portion 1a is cut by an arbitrary number using a gear cutter (not shown). As shown in FIG. 5, a groove portion 1d having a tooth-shaped cross section is formed over substantially the entire area in the axial direction. If the grooves 1d of the iron part 1a (7) are machined using a gear cutting machine before aluminum is cast, there is no need to provide an extra iron part 1b as in the conventional method, and the cutting process of this iron part 1b is not necessary. Since the groove 1d is machined using only a gear cutter, aluminum can be cast into the groove 1d. Further, when aluminum is cast for this groove part, the cage-shaped short-circuit part and the heat sink are integrally cast as in the conventional case. Therefore, according to the present invention, the working process can be shortened, and it has a very great advantage from the viewpoint of saving resources and saving energy. Also,
In the conventional drill, holes 1c are formed in the iron part 1a, which is a magnetic material, using a multi-axis drilling machine, so the number of holes 1c must be an even number due to the mechanism of the multi-axis drilling machine. As a result, the least common multiple of the different number of poles of the driven body 4 (the number of poles is usually an even number) becomes small, and due to this small least common multiple, the driving body 1 and the driven body 4 are synchronized in large numbers.
When the relative rotational speed between the driving body 1 and the driven body 4 is small, there is a drawback that torque fluctuation occurs due to the above-mentioned synchronization even in the slip state. However, if the grooves 1d are machined using a gear cutting machine as in this embodiment, the number of grooves 1d in the iron part 1a can be easily made into an odd number by arbitrarily selecting the module of the gear cutting machine, the pitch diameter, etc. If this is done, the above-mentioned least common multiple will be large and synchronization will be reduced, so stable torque can be obtained even when the relative rotational speed is small. Furthermore, in FIG. 5, if the cutting depth H of the groove 1d by the gear cutting machine is freely changed and selected to an arbitrary value, the torque characteristics as shown in curves A and B shown in FIG. 6 can be easily obtained. can get. The shape of the groove 1d described above is not limited to the shape shown in FIG. 5, but may be the shape shown in FIG. Any hole processing method other than drilling may be used. As described above, the present invention fixes the conductive material and the magnetic material constituting the second connection main body by cutting, not drilling, the inner periphery of the magnetic material at a predetermined interval over the entire circumference. After forming a concave groove that extends over almost the entire axial direction, the conductor to be buried in the concave groove, the shorting part that shorts it, and the heat sink are integrally cast, making it easy to process the groove. The manufacturing of the second connecting body is extremely simple, and has excellent effects in terms of resource and energy conservation.

Furthermore, if the grooves are machined using a gear cutter or the like, the number of conductors can be an odd number, so stable torque characteristics can be obtained even when the relative rotational speed between the first and second connecting bodies is small. . Furthermore, it is possible to change the cutting depth of the groove portion during gear cutting only by cutting using special processing tools and jigs, and there is an effect that various torque characteristics can be easily obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an electromagnetic induction coupling device showing a conventional device;
Figure 2 is a partial sectional view taken along the line ■-■ of Figure 1, and Figure 3
The figure is a sectional view from the inner surface of FIG. 2, FIG. 4 is a partial sectional view of the iron portion 1a in FIG. 1, and FIG. 5 is a partial sectional view of the iron portion 1a showing an embodiment of the present invention. , Fig. 6 is a torque characteristic diagram when the tooth cutting depth H of the iron part 1a in Fig. 5 is changed, and Fig. 7 is a partial cross section of the iron part 1a showing another embodiment of the present invention. There is a diagram. In the figure, 1 is the driving body, 1a and 1b are the iron parts, and 1c
is a hole, 1d is a groove, 2 and 2a are aluminum parts, 2b
4 is a heat sink, 4 is a driven body, 5 is an excitation coil, 6 is a load shaft, 9 is a brush, and 11 is a slip ring.

Claims (1)

[Scope of Claims] 1. A first connecting body that alternately constitutes different poles in the circumferential direction in response to magnetic flux generated in an excitation coil, and an annular body disposed with a radial gap with respect to the different pole surface. In an electromagnetic induction coupling device comprising a magnetic body and a second coupling body which is made of a conductor integrally fixed to the magnetic body and is electromagnetically coupled to the first coupling body, the inside of the magnetic body is After forming concave grooves extending to almost the entire axial direction of the circumferential portion at predetermined intervals over the entire circumference by cutting, not drilling, a conductive portion to be buried in the concave groove and these grooves are formed. Manufacture of an electromagnetic induction coupling device characterized in that a shorting part that shorts a conductive part in a cage shape and a heat sink provided on the outer periphery of the magnetic material are integrally formed by casting and solidifying a melted conductive material. Method. 2. A method of manufacturing an electromagnetic induction coupling device according to claim 1, wherein the concave groove is formed by a gear cutter, and the cross-sectional shape thereof is tooth-shaped. 3. A method of manufacturing an electromagnetic induction coupling device according to claim 1, wherein the concave groove is formed by a broaching machine.