JPH0583772B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] Magnetic particles are filled between the first connecting body and the second connecting body of the present invention, and the magnetic particles are magnetized to create a torque between the two connecting bodies. The present invention relates to an electromagnetic coupling device for transmitting a signal, and particularly to its cooling structure.

[Prior Art] Figure 4 shows a schematic configuration of a conventional electromagnetic coupling device described on pages 2-2 to 2-5 of ``Mitsubishi Electromagnetic Clutches and Brakes (General Catalog), September 1985'', for example. 1 is a cross-sectional view showing an annular ring drive (hereinafter referred to as a first connecting body) which is attached to a rotating shaft 2 driven by a prime mover (not shown) and rotates in conjunction with the rotating shaft 2. ),
Reference numeral 3 denotes a drive (hereinafter referred to as a second
(called the connecting body), and forms the magnetic circuit on the fixed side. 4 is the first connecting entity 1 and the second connecting entity 3
It is a magnetic particle that fills the annular space between the two, becomes solid by magnetization, and becomes a torque transmission medium between the first connecting body 1 and the second connecting body 3. Reference numeral 5 denotes an excitation device disposed on the outer circumferential side of the first coupling main body 1, which is composed of an excitation coil 6 and a stator 7, and generates a magnetic flux Φ by energizing the excitation coil 6 to magnetize the magnetic particles 4. torque is transmitted between the first connecting body 1 and the second connecting body 3. A fixing attachment member 8 is attached to one side of the stator 7, is attached to a fixing part (not shown), and supports the rotating shaft 2 via a bearing 9 between it and the rotating shaft 2. Reference numeral 10 denotes a bracket that connects and secures the second connecting body 3 to the opposite side of the attachment part of the fixing attachment member 8 of the stator 7, and includes a through hole 10.
a and 10b are formed. 11 is a plate that closes the opening of the first connecting body 1 and rotates in conjunction with the first connecting body 1; 12 is a heat radiation fin attached to the plate 11;

Next, the operation will be explained. When the excitation coil 6 is energized while the rotating shaft 2 is rotating together with the first connecting body 1, a magnetic circuit shown by a broken line passing through the stator 7, the first connecting body 1, and the second connecting body 3 is formed. A magnetic flux Φ is generated, and the magnetic particles 4 filled in the annular space between the first connecting body 1 and the second connecting body 3 are magnetized and become solid. At this time, between the magnetic particles 4 and the first connecting body 1,
Alternatively, due to the frictional force acting on the contact surface between the magnetic particles 4 and the second connecting body 3, torque is applied to the first connecting body 1.
The braking force is transmitted to the second connecting body 3, and a braking force is applied to the first connecting body 1. The braking torque generated in the second connecting body 3 is transmitted via the bracket 10 and the stator 7 to a fixing mounting member 8 attached to an external fixed part. The braking torque transmitted from the second connecting body 3 in this manner is transmitted to the fixed part. Therefore, the first connecting body 1 and the second connecting body 3 are coupled by the magnetized magnetic particles 4, and the first connecting body 1 rotates while being braked.
It even stops. In other words, the brakes are applied. To release the brake, the excitation coil 6 may be deenergized. By deenergizing the excitation coil 6, the magnetic flux Φ
disappears, the bond between the magnetic particles 4 is released, and the braking state between the first connecting body 1 and the second connecting body 3 is released.

By the way, since the first connecting body 1 and the second connecting body 3 slip at the contact portion with the magnetic particles 4, kinetic energy is converted into thermal energy at this contact portion, and the temperature rises. When the magnetic particles 4 exceed a permissible temperature, they are oxidized and sintered and lose their function as a torque transmission medium. This limits the temperature rise and limits the torque transmission ability. Therefore, the frictional heat generated at the connecting portion of the first connecting body 1 and the second connecting body 3 is dissipated into the air by heat radiation fins 12 attached to the plate 11. However, heat dissipation by the heat dissipation fins 12 alone cannot sufficiently dissipate the frictional heat generated at the connection between the first connection body 1 and the second connection body 3, and it is difficult to increase the torque transmission capacity. I can't.

For example, as an improved version of this,
There is one disclosed in Japanese Patent No. 27808, and its outline is shown in FIG. In FIG. 5, reference numerals 13 and 14 are a cooling water inlet and a water outlet formed in the second connecting body 3. 15 is the water supply port 13 and the drain port 14
It is a ring-shaped waterway that is connected to the waterway. Cooling water is supplied from the water supply port 13, flows through the water channel 15 to cool the second connecting body 3, and is drained from the drain port 14, so that the heat generated in the connecting portion is released to the outside.

[Problems to be Solved by the Invention] However, in the conventional device described above, since the water channel 15 provided in the second connecting body 3 is located away from the part where frictional heat is generated, it is difficult to release the heat generated by friction to the outside. The ability to do so is small. If, in order to avoid this drawback, the water channel 15 is brought closer to the outer periphery of the second connecting body 3 where frictional heat is generated, the cross section of the magnetic path shown by the broken line will become smaller, making it difficult for the magnetic flux to pass through, and the transmitted torque will be reduced. becomes smaller. Furthermore, since there is saturation development peculiar to the magnetic circuit, even if the excitation current is increased, the torque does not increase, and the characteristics of the transmitted torque with respect to the excitation current do not have linearity, resulting in poor control characteristics. For this reason, the water channel 15 cannot be provided close to the outer periphery of the second connecting body 3, that is, close to the area where frictional heat is generated. Therefore, it is not possible to effectively dissipate the frictional heat generated at the connecting portion between the first connecting body 1 and the second connecting body 3. Furthermore, the first connecting entity 1, the second connecting entity 3,
There is a problem in that the excitation coil 6 and the bearing 9 are heated directly or via the stator 7 and the mounting member 8 by radiant heat due to frictional heat generated by the magnetic particles 4 or by heat conduction. Further, there are other problems in that it is necessary to install water supply and drainage equipment outside the device in order to circulate cooling water to the second connecting body 3, and maintenance such as maintenance of cooling water channels is also required.

This invention was made to solve the above-mentioned problems, and it does not require installation of water supply and drainage equipment, provides a sufficient cooling effect, has a large transmission torque capacity, and has high reliability without the need for maintenance. The purpose is to obtain a device with high performance.

[Means for Solving the Problems] A coupling device according to the present invention includes a plurality of holes formed in the circumferential direction of an annular first coupling body attached to a rotating shaft in parallel with the rotating shaft, and a heat pipe. The heat-receiving parts are inserted into each hole, the heat-radiating part is extended into the end space of the first connecting body, the annular cooling fin is attached to the heat-radiating part, and the annular cooling is performed by rotation of the cooling fan or the annular cooling fin. Cooling air is passed from the inner circumferential side of the fin to the outer circumferential side of the annular cooling fin through the heat radiation part.

[Function] The coupling device of the present invention absorbs frictional heat generated at the coupling part by the heat receiving part inserted into the hole of the first coupling body, transports it to the heat radiating part of the heat pipe, and cools it with cooling air. Dissipates heat to the outside.

[Example] Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 3.
This will be explained based on the diagram. In each of these figures,
Reference numeral 16 denotes a bracket that connects and fixes the stator 7 and the second connecting body 3, and the part facing the end face of the first connecting body 1 is placed at a position apart from the first connecting body 1, so that there is no space between the two. A space is formed in which a heat dissipation part 17b of a heat pipe 17, which will be described later, can extend, and a cooling air inlet 16a is provided on the inner peripheral side.
It has a discharge port 16b on the outer circumferential side. Note that a plurality of holes 1a are formed in the first connecting body 1 in the circumferential direction parallel to the rotation axis. 17, a heat receiving part 17a is inserted into each hole 1a of the first connecting body 1, and a heat radiating part 17b is connected to the first connecting body 1 and the bracket 16.
A heat pipe 18 is a plurality of annular cooling fins, which integrally support the heat dissipation part 17b. It is equipped to do so. 19 is a cooling fan supported by the bracket 16, which supplies cooling air to the inlet 16a,
The heat is discharged through the heat radiating portion 17b on the inner peripheral side of the annular cooling fin 18 to the discharge port 16b.

Next, the operation will be explained. The mechanism by which torque is transmitted from the first connecting body 1 to the second connecting body 3 and the mechanism by which frictional heat is generated are the same as in the conventional example, and their explanation will be omitted.

When the temperature rises in the first connecting body 1, the second connecting body 3, and the magnetic particles 4 due to frictional heat due to torque transmission, the heat dissipating portion 17a inserted into each hole 1a of the first connecting body 1 is activated. The liquid evaporates and the frictional heat is absorbed as latent heat of vaporization. The vapor of the working liquid moves to the heat radiation part 17b and is cooled by the cooling air flowing in from the supply port 16a due to the fan effect caused by the rotation of the cooling fan 19 or the annular cooling fin 18.
Condense. The cooling air is heated by the latent heat of condensation and is discharged from the discharge port 16b.

Since the heat receiving portion 17a is inserted in the vicinity of the portion where frictional heat is generated, it effectively cools the first connecting body 1, the second connecting body 3, and the magnetic particles 4.
Since the heat pipe 17 has an extremely large heat transport capacity, the temperature gradient inside the first connecting body 1, the second connecting body 3, and the magnetic particles 4 is small, and the temperature distribution is made uniform. The annular cooling fin 18 is the heat dissipation part 1
7b and integrally supported, it has a large reinforcing effect against centrifugal force, and furthermore, the number can be increased or decreased as appropriate, and it is possible to provide a large cooling capacity. As a result, when transmitting the same amount of torque as the conventional electromagnetic particle type coupling device, the temperature rise in the coupling portion can be significantly reduced. This means that the electromagnetic particle type coupling device of the present invention can transmit a large torque even though it has the same size as the conventional one.

In addition, since the first connecting body 1 faces the excitation coil 6, the reduction in the temperature rise of the first connecting body 1 means that the temperature of the exciting coil 6 does not increase due to radiant heat from the first connecting body 1. Not only that, but it also has the effect of cooling the excitation coil, making it possible to use an inexpensive excitation coil with low heat resistance. Furthermore, reducing the temperature rise of the first connecting body 1 also has the effect of suppressing the temperature rise due to heat transfer in the bearing 9 fitted to the rotating shaft connected to the first connecting body 1.

Furthermore, cooling by the heat pipe 17 does not require maintenance, and does not require maintenance of cooling channels in water cooling.

In the above embodiment, a case has been described in which the heat radiating part 17b is provided in the space between the first connecting body 1 and the bracket 16, but the heat radiating part 17b is provided in the space between the first connecting body 1 and the mounting member 8. It may be provided in a space, or the heat radiating portions 17b may be arranged on both sides.

By the way, in the above explanation, the first coupling body rotates and the second coupling body is fixed as a magnetic particle type electromagnetic coupling device, that is, one applied to a brake device. The present invention can also be applied to a clutch device in which the two connecting bodies rotate.

[Effects of the Invention] As explained above, in the present invention, a plurality of holes are formed in the circumferential direction of the annular first connecting body attached to the rotating shaft in parallel with the rotating shaft, and the heat receiving portion of the heat pipe is connected to each hole. The heat pipes are inserted into the respective holes, the heat dissipation part of the heat pipe is extended into the end space of the first connecting body, and an annular cooling fin is installed in the heat dissipation part of the heat pipe, and the annular cooling is performed by rotation of the cooling fan or the annular cooling fin. Since the cooling air is passed from the inner circumferential side of the fin to the outer circumferential side of the annular cooling fin through the heat dissipation part of the heat pipe, the magnetic particle type electromagnetic coupling device according to the present invention has the following advantages: (a) As the annular cooling fin rotates, Due to the viscosity of the air, the air between the cooling fins rotates and generates centrifugal force, which causes air to flow in the radial direction, allowing effective heat radiation from the heat pipe heat radiation section.

(b) Since the heat dissipation part of the heat pipe is integrally supported by the annular cooling fin, it can withstand high-speed rotation without being deformed by the centrifugal force that accompanies rotation.

(c) Since the heat of the first connecting body interposed between the excitation device and the second connecting body is effectively radiated by transporting it from the heat receiving part of the heat pipe to the heat radiating part, the heat generated by the magnetic particles is reduced. Not only heat but also heat generated in the excitation device and the second connecting body can be efficiently radiated and cooled.

(d) Since the area immediately adjacent to the magnetic particles is cooled, the temperature of the magnetic particles decreases, and the permissible amount of frictional heat generated per unit volume in this area is large.

(e) Since the heat generated in the excitation device can also be cooled, an excitation coil with low heat resistance can be used and the device can be made inexpensive.

(f) Since the temperature rise of the first connected body is smaller than the temperature rise of the second connected body, the air space does not expand in an annular shape due to the temperature rise of the device, and the magnetic particles due to the temperature rise are There is no reduction in transmitted torque due to insufficient torque.

(g) There is no need to provide water supply and drainage equipment to cool the first connecting body, and high reliability can be achieved without maintenance.

Many other effects can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a magnetic particle type electromagnetic coupling device according to an embodiment of the present invention, FIG. 2 is a front view showing a first coupling body according to the present invention, and FIG. 3 is a heat pipe according to the present invention. 4 and 5 are cross-sectional views of a conventional magnetic particle type electromagnetic coupling device, respectively. In the figure, 1 is the first connecting body, 1a is the hole,
2 is a rotating shaft, 3 is a second connecting body, 4 is a magnetic particle, 5 is an excitation device, 17 is a heat pipe, 17a
17b is a heat receiving part, 17b is a heat radiating part, 18 is an annular cooling fin, and 19 is a cooling fan. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. An annular first connecting body attached to a rotating shaft and having a plurality of holes formed in a circumferential direction parallel to the axis center of the rotating shaft; an inner periphery of the first connecting body; a second connecting body disposed on a concentric axis with an annular cavity in between; magnetic particles filled in the annular cavity between the first connecting body and the second connecting body; an excitation device that magnetizes the magnetic particles and transmits torque between the respective connecting bodies; a heat receiving part is inserted into a plurality of holes formed in the first connecting body, and a heat dissipating part is attached to the first connecting body; a plurality of heat pipes extending into the end space of the heat pipes and having a predetermined amount of evaporative working liquid sealed inside; a plurality of annular cooling fins that integrally support the heat dissipation portions of the plurality of heat pipes; A magnetic particle type electromagnetic coupling device characterized in that a cooling air path is configured from the circumferential side to the outer circumferential side of the annular cooling fin through the heat dissipation part of the heat pipe.