JPH0126895Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a magnetic particle type electromagnetic coupling device, particularly to an improvement in the structure.

[Prior art]

FIG. 1 is a sectional view of an example of a conventionally proposed magnetic particle type electromagnetic coupling device. In the figure, numeral 1 denotes a rotating shaft which has a spline fitting portion 1a on its inner periphery. Reference numeral 2 denotes a driven member fixed to the rotating shaft 1, which is composed of two annular members 2a and 2b and has an annular groove 2d opening on the outer periphery. 3 is a cylindrical drive member having a connecting portion 3a that faces the connecting portion 2c of the driven member 2 via an annular gap in the radial direction, and 4 is enclosed in the annular gap between the connecting portions (between 2c and 3a). A case 5 is attached to the annular groove 2d of the driven member 2, and a case 6 is wound around the case 5 to magnetize the magnetic particles 4 and attach them to the driven member 2 and the drive member 3.
7 is a bolt that fixes the rotating shaft 1 and the driven member 2; 8 is a washer for the bolt 7; 9 is a slip ring for supplying power to the electromagnetic coil 6; It is attached to the other end of the shaft 1 and connected to the electromagnetic coil 6 via a lead wire 10 that passes through the hole 1b of the rotating shaft 1 and the passage 2e of the driven member 2. Reference numeral 11 is an external mounting plate provided at the end of the drive member 3 and connected to a drive source (not shown). Reference numeral 12 denotes a bracket whose outer peripheral portion is fixed to the drive member 3, and reference numeral 13 denotes a bearing that rotatably supports the driven member 2 and the drive member 3 via the bracket 12.

The conventionally proposed magnetic particle type electromagnetic coupling device is constructed as described above, and its operation is well known. When the electromagnetic coil 6 is deenergized, the magnetic particles 4 are not magnetized, and the torque is not transmitted from the drive member 3 to the driven member 2. Therefore, the rotating shaft 1 fixed to the driven member 2 remains stationary. When the electromagnetic coil 6 is energized, a magnetic flux Ф is generated as shown by the broken line in FIG. Torque is transmitted from 2 to the rotating shaft 1 to drive a driven body (not shown). This transmitted torque can be controlled by changing the excitation current of the electromagnetic coil 6.

In the conventional device configured as described above, the driven members 2a, 2b, which are two annular members, and the rotating shaft 1 are fixed with the bolts 7, so it is difficult to screw the bolts 7 into the driven members 2a, 2b and the rotating shaft 1. In addition, since the bolts are tightened at a small radius, the number of bolts 7 must be increased, resulting in poor workability.

Further, since the head of the bolt 7 protrudes in the axial direction, there is a drawback that the magnetic particles 4 are agitated.

[Summary of the idea]

This invention was made for the purpose of improving such drawbacks, and the axial dimension is shortened by fixing the rotating shaft to the second connecting body formed of two substantially symmetrical annular members by electron beam welding. The present invention provides a magnetic particle type electromagnetic coupling device with improved workability.

[Example of idea]

FIG. 2 is a cross-sectional view showing an embodiment of this invention, in which numerals 3 to 6 and 9 to 13 are the same as the conventional device described above. 14 is a rotating shaft with a spline fitting part 1 on the inner peripheral surface.
4a and a hole 14b for the lead wire 10. Reference numeral 15 denotes a driven member, which is a second main body of connection, which is fixed to the rotating shaft 14 by electron beam welding (section A in the figure), and is composed of two substantially symmetrical annular members formed with an annular groove 15d open on the outer periphery. 15a,1
5b, and the connecting portion 15c faces the connecting portion 3a of the drive member 3, which is the first connecting main body, with an annular gap interposed therebetween. 15e is a passage for the lead wire 10.

The operation of this embodiment is the same as that of the conventional device, so a description thereof will be omitted.

Now, in this invention, as mentioned above, the fixed part A of the rotating shaft 14 and the driven member 15 is fixed by electron beam welding, so the bolt 7 for fixing as in the conventional case can be eliminated, and the axial dimension can be shortened. Particularly when applied to automobiles, it satisfies the strict requirement of shortening the axial dimension and achieves remarkable effects.

In addition, three parts, the two annular members 15a and 15b and the rotating shaft 14, can be fixed in one step, improving work efficiency.

Further, by avoiding welding near the lead wire 10 due to intensive welding, heat influence on the lead wire 10 can be avoided.

[Effect of idea]

As explained above, this device has good workability and a shortened axial dimension by fixing the second connecting body formed by two approximately symmetrical annular members by electron beam welding. The effect of preventing thermal influence on the lead wire of the coil can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a conventionally proposed magnetic particle type electromagnetic coupling device, and FIG. 2 is a sectional view showing an embodiment of this invention. In the figure, 1 and 14 are rotating shafts, 2 and 15 are driven members, 3 is a drive member, 4 is a magnetic particle, 5 is an electromagnetic coil, and A is a fixed portion. In addition,
The same reference numerals in each figure indicate the same parts.

Claims (1)

[Scope of utility model registration request] A first connecting body having a cylindrical first connecting part made of a magnetic material, and two substantially symmetrical annular members facing the radially inner circumferential surface of the first connecting part with an annular gap in between. a second connecting body having a second connecting part made of material; a rotating shaft to which the second connecting body is fixed; magnetic particles enclosed in the annular gap; An electromagnetic coil that magnetizes particles to control the connection state between the first connecting body and the second connecting body, wherein the second connecting body and the rotating shaft are fixed by electron beam welding. A magnetic particle type electromagnetic coupling device featuring: