JPS628657Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a magnetic particle type electromagnetic coupling device, the purpose of which is to communicate the interior and exterior, including a coupling gap, through a communication path, and to allow the flow of air that expands and contracts due to the rise in internal temperature. (collection effect) can be achieved smoothly, and at the same time, it is possible to prevent external dust, etc. from entering the interior.

The above will be described in detail with reference to the embodiment (coil rotating type) shown in FIGS. 1 to 5. In each figure, 1 is a drive rotor that is the main body connected to the outside, and 2 is an excitation coil that is housed in a recess 3 of the drive rotor 1 and fixed to the recess 3 with resin 4, which is molded from synthetic resin. It is wound around bobbin 5. A conductive terminal 6 has one end connected to the excitation coil 2, and is fixed to the resin 4 on the drive rotor 1. Although not shown, another conductive terminal is provided at a position symmetrical to the conductive terminal 6. 7 is a driven rotor which is the main part of the inner connection, forming an annular gap g between it and the driving rotor 1;
Magnetic particles 8 are enclosed in this annular gap g. 9 indicates this driven rotor 7, annular shape and plate 1.
0 is a cylindrical driven shaft fixed by a bolt 11, and a shaft (not shown) is fixed thereto. This annular plate 10 closes the left opening of the driven shaft 9. 1
2 is fixed to the other side of the drive rotor 1 with a screw 13, and constitutes one shielding member together with a ring-shaped plate 15, which will be described later. A bearing 1 is installed between the bracket 12 and the driven shaft 9.
4 is press-fitted and fixed. This bearing 14 supports the driving rotor 1 and the driven rotor 7 so as to be rotatable with respect to each other. Further, the bracket 12 is die-cast molded from aluminum material, and has a cylindrical portion 12a into which the outer ring of the bearing 14 is press-fitted, and an arc-shaped axial portion at two symmetrical locations of the cylindrical portion 12a. The recess 12b, a contact portion 12c that receives the left side of the outer ring of the bearing 14 in the axial direction, and an arcuate radial recess 12d located in the contact portion 12c and communicating with the above-mentioned axial recess 12b. An annular flange 12e facing the outer circumference of the drive shaft 9 via an annular gap;
An escape groove 12f located on the outer side of the bracket 12 and in which lead terminals to be described later face each other is simultaneously formed integrally by aluminum die casting. 15
is a ring-shaped plate whose one end abuts the outer ring of the bearing 14 and whose other end faces the outer periphery of the driven shaft 9 with a small gap therebetween, and is formed of a relatively rigid iron plate or the like. 15a are communicating holes formed in two symmetrical locations of this ring-shaped plate 16;
The positions of these communication holes 15a are determined by the respective axial recesses 12b.
facing the opening of. A holder 16 is fixed to the side of the bracket 12 with a screw 17 via a ring-shaped plate 15, and is die-cast from aluminum. Reference numeral 18 denotes a power supply device that supplies power to the excitation coil 2, which includes a pair of slip rings 20, 21 fixed to the cylindrical portion 16a of the holder 16 via a molding material 19, and these slip rings 20, 21.
A pair of lead terminals 22 and 23 which are opposing members respectively connected to 21, and these lead terminals 2
Shrink tubes 24 and 25 that insulate and protect 2 and 23
The excitation coil 2 is powered by a power source through a pair of brushes (not shown) that are in sliding contact with a pair of slip rings 20 and 21, respectively. The lead terminals 22 and 23 described above are connected to the ring-shaped plate 1.
It faces the opening of the communication hole 15a of No. 5 with a predetermined gap therebetween. 26 is a screw for connecting and fixing one end of the lead terminal 21 to the conductive terminal 6; 27 is an annular plate that is the other shielding member fixed to one side of the drive rotor 1; A is the interior including the connecting gap g; B is the outside that is shielded from this inside A.

The operation of the embodiment configured as above will be explained. When the drive rotor 1 is rotating, the brush slip rings 20, 21 lead terminals 22,
When the excitation coil 2 is supplied with power and excited through the dotted line, the magnetic flux φ flows through the magnetic path shown by the dotted line and the magnetic particles 8 are solidified, so the drive rotor 1 and the driven rotor 7 are coupled, and the drive rotor 1 is transmitted to a load (not shown) through the driven rotor 7 and the driven shaft 9.

Now, in the embodiment configured as described above, the interior A including the connecting gap g and the exterior B are almost reliably shielded, and therefore the exterior B of the magnetic particles 8 in the interior A is
This prevents dust, oil, etc. from outside B from entering inside A.

That is, the left side of the drive rotor 1 is an annular plate 27.
The left side of the driven shaft 9 is closed by an annular plate 10, and the right side of the drive rotor 1 is almost closed by a bracket 12, a bearing 14, the driven shaft 9 and a ring plate 15. .

By the way, when the drive rotor 1 and the driven rotor 7 are connected, each connection part is heated to an extremely high temperature due to slip heat, so the air inside the interior A expands significantly and its volume increases, causing the inside A to Since the volume is constant, the expanded air will seek escape outside B. This expanded air reaches the outside B through the gap between the inner and outer rings of the bearing 14, so the grease filled in the bearing 14 flows out to the outside B of the bearing 14 due to the above-mentioned pressurized air, and conversely, the temperature of each joint increases. As the air contracted by the following is forced into the interior A through the gap between the inner and outer rings of the bearing 14, the amount of grease on the bearing 14 is insufficient, and a seizure phenomenon occurs. The driven rotor 7 rotates together with the driven rotor 7. Furthermore, the magnetic particles 8 contain oil due to the grease leaked into the interior A, and air containing oil enters the interior A, causing slippage between the drive rotor 1, the magnetic particles 8, and the driven rotor 7. Stable connection operation cannot be obtained.

Therefore, in this embodiment, an axial recess 12b and a radial recess 12d connected thereto are provided at two symmetrical locations on the bracket 12, and an axial communication path 28 and a radial recess connected thereto are provided between the outer ring of the bearing 14. Two directional communication passages 29 are formed, and the communication holes 15a of the ring-shaped plate 15 are opposed to the openings on the outside B side of the axial communication passages 28, so that the interior A and the exterior B are located at two symmetrical locations. axial and radial communication passages 28, 29 and communication holes 15a. Therefore, even if the air inside the interior A expands, the expanded air is forced to the outside B through the two axial and radial communication passages 28, 29 and the communication hole 15a, without forcing the bearing 14. In addition, the contracted air is transferred to the communication path 2 mentioned above.
Since the grease is pumped into the interior A through 8 and 29 (performing a so-called breathing action), the life of the grease on the bearing 14 can be extended, and the grease on the drive rotor 1 and the driven rotor 7 can be
Since the low temperature fresh air from the outside B is sucked into the inside A, the rise in temperature of the inside A is suppressed and the inside A is cooled, thereby achieving stable connection operation. Furthermore, as shown in FIGS. 1 and 5, a pair of lead terminals 22 and 23 are arranged to face each other with a predetermined gap in the opening on the outside B side of each communication hole 15a of the ring-shaped plate 15, and the communication hole 15a Since the opening on the outside B side is widely covered by the lead terminals 22 and 23, dust, oil, etc. from the outside B can be prevented from entering the communication hole 15a due to the expansion and contraction of the air inside the inside A. It is possible to substantially prevent dust, oil, etc. from entering. In addition, the axial and radial communication passages 28,
29 is bent, and the diameter of the communication passages 28, 29 and the size of the annular gap between the annular collar portion 12e and the driven shaft 9 are set small enough to allow air to flow. It is also possible to reliably prevent the magnetic particles 8 from flowing out to the outside B through the gap. Further, the axial and radial recesses 1 form communication passages 28 and 29 that communicate the inside A and the outside B.
2b and 12d can be integrally formed at the same time when the bracket 12 is die-cast, so they can be easily manufactured at low cost. Moreover, since the existing lead terminals 22 and 23 are used as opposing members that face each other so as to cover the opening on the outside B side of the communication hole 15a, no new additional parts are required, and the structure can be easily and inexpensively constructed.

As described above, this invention provides a communication path that communicates between the inside and the outside in one of a pair of shielding members that are provided on both sides of the outer connecting body and seals and shields the inside including the connection and void from the outside. Since a facing member is provided at the opening on the outside side of the hole with a predetermined gap in between, the internal air that expands and contracts due to the internal temperature rise can be prevented from flowing out to the outside or flowing into the inside (so-called breathing effect). ) is carried out extremely smoothly, suppressing the rise in internal temperature, improving cooling efficiency, and preventing the intrusion of external dust through the communication path, resulting in stable connection operation.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of this invention, FIG. 2 is a sectional view of the main part of the bracket 12, FIG. 3 is a side view of the ring-shaped plate 15, and FIG. Figure 5 shows lead terminals 22 and 23.
FIG. 3 is a side view showing a state in which the communication hole 15a faces an opening on the outside B side. In the figure, 1 is the drive rotor, 2 is the excitation coil,
7 is a driven rotor, 8 is a magnetic particle, 9 is a driven shaft, 10 and 27 are plates, 12 is a bracket,
12b, 12d are recesses, 14 is a bearing, 15
15a is a ring-shaped plate, 15a is a communication hole, 16 is a holder, 22 and 23 are route terminals, and 28 and 29 are communication paths. Note that the same reference numerals in each figure indicate the same parts.

Claims (1)

[Claims for Utility Model Registration] (1) Inner and outer connecting bodies facing each other through a connecting gap, magnetic particles that are enclosed in the connecting gap and magnetized to connect the inner and outer connecting bodies, and the outer connecting body a pair of shielding members provided on both sides to shield the interior including the connecting gap from the exterior; a communication passage provided on one of the shielding members for communicating the interior and exterior; and an opening on the exterior side of the communication passage. A magnetic particle type electromagnetic coupling device comprising a facing member provided on one of the shielding members to face the shielding member with a predetermined gap therebetween. (2) The magnetic particle type electromagnetic coupling device according to claim 1, wherein one of the shielding members comprises a bracket and a ring-shaped plate.