JPH0412259Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a magnetic particle type electromagnetic coupling device, and particularly to a structure for preventing intrusion of bearing grease into the coupling portion.

[Conventional technology]

In general, in this type of conventional device, magnetic particles are sealed in the gap between the opposing connecting surfaces of each of the first and second connecting bodies, and when the electromagnetic coil is energized, the magnetic particles are magnetized and each connecting surface is magnetized. I'm trying to connect the spaces between them.

[Problem that the invention attempts to solve]

However, when this connection is made, slip heat is generated from the connection part and the temperature of the entire device rises, but if the amount of work during connection is too large, the temperature rise will be significant.
The grease sealed inside the bearing liquefies and enters the joint, obstructing the movement of the magnetic particles, or causing sintering of the magnetic particles, resulting in problems where the desired performance cannot be achieved. Was.

This invention was made in order to eliminate the above-mentioned drawbacks, and uses a simple structure to prevent bearing grease from entering the connecting portion.

[Means for solving problems]

The magnetic particle type electromagnetic coupling device according to this invention has a small gap in the radial direction from the inside between the bracket fixed to the first coupling body and the bearing installed between the bracket and the second coupling body. A ring-shaped plate is fixed to the bracket, and a communication path communicating with the outside is formed between the plate and the bracket.

[Effect]

In this invention, bearing grease is discharged through a small radial gap between the bracket and the bearing, an axial communication path, and a communication path leading to the outside between the bracket and the plate.

〔Example〕

An embodiment of this invention shown in FIGS. 1 and 2 will be described below. In FIG. 1, 1 is a rotating shaft having a spline fitting part 1a on a part of its inner circumference;
is a driven member which is a second connection main body fixed to the rotating shaft 1, and has a second connection portion 2a on the outer periphery and an annular groove 2b opening on the outer periphery. Reference numeral 3 denotes a drive member which is a first connection main body, and a first drive member which faces the second connection part 2a in the radial direction with an annular gap g interposed therebetween.
It has a connecting part 3a. 4 is a magnetic particle sealed in the annular gap g, and 5 is an electromagnetic coil built into the annular groove 2b of the driven member 2, which magnetizes the magnetic particle 4 to connect the drive member 3 and the driven member 2. control. 6 is a bobbin on which the electromagnetic coil is wound; 7 is a cover fixed to the drive member 3 to prevent the magnetic particles 4 from leaking to the outside; 8 is a cover mounted on the rotating shaft 1 and attached to the electromagnetic coil 5; A slip ring for supplying power to the hole 1b of the rotating shaft 1 and the driven member 2.
It is connected to the electromagnetic coil 5 via a lead wire 9 passing through the passage 2c. Reference numeral 10 denotes a bracket whose outer circumferential portion is fixed to the drive member 3 with screws 11, and whose inner circumferential portion is rotatably supported by the rotating shaft 1 via a bearing 12, with a small radial gap 10a between the bracket and the bearing 12. and axial communication path 10
b. 13 has one end attached to the bearing 1 above.
This is a ring-shaped plate which is fixed to the bracket 10 by screws 14 so as to abut the outer ring of the bracket 2 and form a radial communication path 10c with the bracket 10. Note that A is the interior including the annular gap g, and B is the exterior that is shielded from this interior.

As is well known, when the electromagnetic coil 5 is deenergized, the magnetic particles 4 are not magnetized, so no torque is transmitted from the drive member 3 to the driven member 2, and the driven member 2 and the rotating shaft 1 remain stationary. ing. Next, when the electromagnetic coil 5 is energized,
A magnetic flux φ is generated as shown by the broken line in FIG. 1, and the magnetic particles 4 are magnetized, and torque is transmitted from a drive source (not shown) to the drive member 3 → magnetic particles 4 → driven member 2 → rotating shaft 1, A driven shaft (not shown) that is spline-fitted thereto is driven.

By the way, in the above configuration, a small radial gap 10a formed by the bracket 10 and the bearing 12 is formed from the space in the interior A including the annular gap which is the connecting part,
Since the structure is such that the communication path 10b in the axial direction and the communication path 10c formed by the bracket 10 and the plate 13 are connected to the external space B, the bearing grease liquefies due to the temperature rise of the device and the small gap in the radial direction is formed. Even if it leaks to 10a, bracket 1
0 is constantly rotated by a driving source, and the grease is guided to the larger diameter side by the centrifugal force, and is discharged to the outside B through the communicating passages 10b and 10c, thus preventing the bearing grease from entering the coupling part. can be prevented.

Moreover, as shown in FIG. 2, the small gap 1 in the radial direction
0a has a shape in which the portion communicating with the communication path 10b has the largest diameter, so that the bracket 10 and the bearing 12, which are constantly rotated by the drive source,
In the small radial gap 10a formed by the rotation, the centrifugal force caused by the rotation causes the bearing grease to
That is, the bearing grease gathers in the communication path 10b and the effect of releasing the bearing grease to the outside B is further improved.

[Effect of idea]

As explained above, this device communicates from the inside through a small radial gap formed by the bracket and the bearing, an axial communication path leading to this, and a communication path formed by the bracket and ring-shaped plate to the outside. As a result, the grease flowing out of the bearing is discharged to the outside through the communication passage due to centrifugal force, and an excellent effect can be obtained in that the grease can be prevented from entering the internal communication passage.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of this invention, and FIG. 2 is a side view of the main part of the bracket. In the figure, 1 is a rotating shaft, 2 is a driven member, 3 is a drive member, 4 is a magnetic particle, 5 is an electromagnetic coil, 10 is a bracket, 10a is a small radial gap,
10b is an axial communication path, 10c is a communication path, 12 is a bearing, and 13 is a ring-shaped plate.

Claims (1)

[Claims for Utility Model Registration] (1) An annular first connecting body having a first connecting part made of a magnetic material, located inside the first connecting body and facing the first connecting part through a gap. a second connecting body having a second connecting part made of a magnetic material; a rotating shaft on which the second connecting body is provided so that it cannot rotate relative to each other; and magnetic particles sealed in a gap between the first connecting part and the second connecting part. , an electromagnetic coil that magnetizes the magnetic particles and controls the connection between the first connecting body and the second connecting body, a bracket provided on the first connecting body, and an interposed between the bracket and the second connecting body. A ring-shaped plate is provided to fix the bearing to the bracket, and a small gap in the radial direction formed between the bracket and the bearing, and a ring-shaped plate that communicates with the small gap is provided. An axial communication path is provided, and further a radial communication path is formed by the bracket and the plate and communicates with the axial connection path, and the radial communication path is opened in the axial direction to the outside. A magnetic particle type electromagnetic coupling device characterized by: (2) Utility model registration claim 1, characterized in that the small radial gap formed by the bearing and the bracket is shaped such that the portion communicating with the axial connection path has the largest diameter. The magnetic particle type electromagnetic coupling device described in .