JPH0678772B2 - Magnetic particle type electromagnetic braking device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a magnetic particle type electromagnetic braking device.

[Conventional technology]

FIG. 2 is a cross-sectional view showing a conventional magnetic particle type electromagnetic braking device,
FIG. 3 is a partial cross-sectional view showing a heat pipe used in this conventional device. In FIG. 3, (1) is a yoke which is an outer circumferential side stator containing an exciting coil (2),
A pair of symmetrical magnetic poles (3) on the inner circumference,
It has (3 '). (4) and (5) are brackets attached to both ends of the yoke (1), (6)
Is a rotor having a cylindrical portion, and the rotor is integrally coupled with a rotor shaft (7) which is motively connected to a rotating body (not shown), and a bearing (8) is provided at the rotor shaft portion. Is supported on the bracket (5) via. (10) is a plate that closes the opening of the cylindrical portion of the rotor (6), (11)
Is an inner peripheral side stator fixed to the bracket (4), and magnetic particles (12) are provided in the cylindrical space between the outer peripheral surface of the stator and the inner peripheral surface of the cylindrical portion of the rotor (6). ) Is filled. (13) is a hollow cylindrical sealed tube (14), a wick (15) mounted on the inner peripheral wall of the sealed tube for performing a capillarity, and a working fluid having a vaporizing property and reduced pressure sealed inside. A heat pipe constituted by (16), wherein a plurality of the heat pipes (13) are provided near the working portion of the rotor (6). (17) is the sealed tube (1
4) Cooling fins provided on the outer edge of the blower (1
It is cooled by the cooling air from 8).

Next, the operation will be described.

By supplying power to the exciting coil (2), a magnetic flux whose magnetic path is shown by a dotted line is generated, whereby the magnetic particles (12) are magnetized and solidified, and as a result, the rotor (6) and the stator (11) Are dynamically connected, so that the rotor (6) side, and hence the braked object connected thereto, is braked.

During this braking, heat proportional to the braking torque and the number of rotations of the rotor (6) is generated in the magnetic particles (12) and the operating parts of the rotor (6) and the stator (11) that are in contact with the magnetic particles. . This heat is released to the outside by the heat pipe (13).

Next, the torque transmission path will be described.

First, the rotor shaft (7) → rotor (6) → magnetic particles (12) → stator (11) → bracket (4) → yoke (1) → bracket (5) are transmitted from a rotary shaft (not shown),
Finally, it is transmitted to the fixed frame (19).

[Problems to be solved by the invention]

Since the conventional braking device is configured as described above, the number of parts to which torque is transmitted is large and the length to be transmitted is also long. Therefore, there is a problem that all the components to which torque is transmitted need strength and are heavy. .

Further, since the yoke (1) and the stator (11) are connected by the bracket (4), the blower (18) must be attached to the outside of the bracket (4) so that the blower (18) becomes large in the axial direction. The heat dissipation efficiency of the heat pipe is poor because the wind flow is obstructed by the bracket (4), and there is a fatal defect that the magnetic particles are seized due to the temperature rise at the time of high load and the operation becomes impossible. There is a problem that the applicable load range is limited to a low load.

Further, looking at the magnetic circuit, the yoke (1) → bracket (4) → internal stator (11) → rotor shaft (7) → bearing (8) → bracket (5) → yoke (1) called yoke (1). Forming a magnetic leakage circuit without an air gap between the rotor and the rotor (6), and the magnetic particles (12) form an outer peripheral surface with the stator (11) and an inner peripheral surface of the cylindrical portion of the rotor (6). There was a problem that the magnetic particles (12) gathered in the axial center clearance between the inner stator (6) and the rotor shaft (7) without gathering in the cylindrical space between them and the torque decreased.

The present invention has been made to solve the above problems, and an object thereof is to obtain a lightweight and compact device in which the torque transmission path is simple, the transmission length is short, and magnetic leakage is eliminated.

[Means for solving problems]

In the magnetic particle type electromagnetic braking device according to the present invention, the rotor shaft having the fixing member inserted therein is provided, and the heat pipe heat radiation portion and the ventilation means are provided on the side opposite to the bracket.

[Action]

According to the present invention, not only the heat pipe and the ventilation means can be arranged without receiving the interference of the bracket, but also the torque transmission path can be simplified and a magnetic circuit having no leakage magnetic path can be constructed.

Example of Invention

 An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, (5) is a bracket for connecting the yoke (1) which is the outer peripheral side stator and the inner peripheral side stator (11),
(7) is inserted into this bracket (5) and the bearing (8)
A rotor shaft rotatably supported via (20) is a ventilation frame.

The operation is the same as that of the conventional device, and will not be described.

Next, the torque transmission path will be described.

First, the rotor shaft (7) → the rotor (6) → the magnetic particles (12) → the stator (11) → the bracket (5) is transmitted from a rotary shaft (not shown), and finally to the fixed frame (19). .

Compared with the conventional device, the number of the two parts, the bracket (4) and the yoke (1), is reduced, and the length of the torque transmission path is significantly shortened. That is, since the bracket (4) is unnecessary and no torque is applied to the yoke (1), it is possible to greatly simplify the strength design.
Also, in terms of cost, the cast bracket (4) is reduced by one, which leads to cost reduction.

Further, in the conventional device, the blower had to be attached to the outside of the bracket (4), but in the present invention, the blower can be incorporated inside the device and the total length of the device can be shortened. Further, in the conventional device, the bracket (4) blocks the air flow of the blower (19), but in the present invention, it is possible to eliminate the wind blocking member.
Cooling efficiency is significantly improved.

Furthermore, by eliminating the bracket (4), the leakage flux circuit found in the conventional device can be blocked, and the magnetic efficiency is significantly improved.

〔The invention's effect〕

As described above, according to the present invention, the torque transmission path is configured to be significantly shortened, and the magnetic leakage circuit is eliminated, so that the entire device is lightweight and compact, the cost can be reduced, and the heat capacity can be increased. There is.

As described above, according to the present invention, it is possible to obtain a magnetic particle type electromagnetic braking device that is small in size, light in weight, inexpensive, and excellent in cooling efficiency and magnetic efficiency. In particular, it is possible to increase the heat capacity by increasing the cooling efficiency. To expand the applicable load range of
In addition to being compact and lightweight, it has a significant effect in practice.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing a magnetic particle type electromagnetic braking device according to an embodiment of the present invention, and FIGS. 2 and 3 are sectional views showing a conventional device. (1) is a yoke, (2) is an exciting coil,
(6) is a rotor, (7) is a rotor shaft, (11) is an internal stator, (12) is magnetic particles, (13) is a heat pipe, (18)
Is a blower. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A bracket having an outer peripheral side stator and an inner peripheral side stator, which are concentrically arranged, wherein the outer peripheral side stator and the inner peripheral side stator are provided on one end side in an axial direction. A fixed member that is connected to the fixed member and is non-rotatably locked, a rotor shaft that is rotatably supported by being inserted into the fixed member, and a radial gap between the outer peripheral side stator and the inner peripheral side stator. A rotor fixed to the rotor shaft, which has an annular working surface arranged in
Magnetic particles loaded in the radial gap between the rotor and the inner peripheral side stator, provided on the outer peripheral side stator, the outer peripheral side stator and the inner peripheral side stator part of the magnetic path age,
An exciting coil for generating a braking torque between the inner peripheral side stator and the rotor by magnetizing the magnetic particles, provided near the operating surface of the rotor, and a heat radiating portion is projected to the opposite bracket side. A heat pipe, and a ventilation unit arranged near the heat radiating unit of the heat pipe for cooling the heat radiating unit, wherein at least a part of the ventilation unit is located radially inward of the heat pipe. Magnetic particle type electromagnetic braking device.