JPS6151689B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic particle type electromagnetic coupling device having a structure in which a magnetic device having an excitation coil is disposed on the radially inner circumferential surface of each coupling portion in which magnetic particles are enclosed.

As a conventional example of this kind, the one described in Japanese Utility Model Publication No. 51-20351 has been proposed, but in this one, the driven part is located between the drive part and the drive part cover that is integrally fixed to the drive part. This is a double-connected structure in which magnetic particles are respectively sealed in the cavity between the driven part and the drive part and in the cavity between the driven part and the drive part cover.

However, with this structure, the heat generated at the outer connection is cooled down through the outer fins, but the heat generated at the inner connection is due to the fact that the outer connection is the heat source and the excitation located on the inner side. Since the coil is the heat source, there is almost no heat dissipation and the heat is trapped in the inner peripheral joints, which causes the temperature of each joint to rise significantly, resulting in the burning of magnetic particles, increased wear, and the effects of heat. As a result, the service life is shortened and sufficient connection torque cannot be obtained. Moreover, the hollow part is arranged twice in the radial direction,
In addition, since the structure has interconnected cavities, it is difficult to uniformly disperse the magnetic particles in each cavity.
This method has drawbacks such as different connection torques occurring at the inner and outer connecting portions and poor responsiveness.

In addition, if a double connection structure is adopted in which connection parts are placed on the inner and outer peripheries, the air space will be doubled and the ampere turns of the excitation coil will increase, resulting in an increase in the size of the stator and excitation coil, which in turn will increase the overall size of the device. It has the disadvantage of being large and expensive.

The present invention provides an excellent magnetic particle type electromagnetic coupling device that eliminates the above-mentioned drawbacks.

The embodiment shown in FIG. 1 will be described below.
In the figure, reference numeral 1 denotes a drive member which is a first connecting body coupled to a drive source (not shown), and is manufactured by die-casting aluminum. Reference numeral 2 denotes a connecting member having a first connecting surface 2a on the inner periphery, which is formed into a cylindrical shape from a magnetic material such as iron. They are integrally connected and only the first connecting surface 2a is exposed on the inner surface. 3 is a joint surface between the drive member 1 and the connecting member 2, 4 is a shaft connected to a load side (not shown), and 5 is fixed to this shaft 4, and is a first connecting surface 2a of the connecting member 2.
The driven member is a second connection main body consisting of a connection part 5b having a second connection surface 5a facing each other via a single annular cavity g on the radially inner circumferential side of the drive member. It is formed. Reference numeral 6 denotes an annular non-magnetic member that magnetically divides the connecting portion 5b of the driven member 5 into two.
fixed to connect. 7 is a magnetic particle enclosed in a single annular cavity g; 8 and 9 are magnetic particles 7 fixed to both sides of the driven member 5, respectively;
A labyrinth 10 is fixed to the right opening side of the drive member 1 and cooperates with the labyrinth 9 to prevent the magnetic particles 7 from falling out of the single annular space g. A dustproof cover 11 having a labyrinth function to prevent this is a bearing mounted between the drive member 1 and the shaft 4, and is positioned by snap springs 12 and 13. Reference numeral 14 denotes a connecting portion 5 that is installed on the inner peripheral side in the radial direction of the driven member 5 and is divided into two.
The stator has a pair of annular magnetic poles 14a facing each other with a space between them on the radial inner circumferential surface of b.The stator is made of a magnetic material such as iron, and rotation is prevented by a rotation prevention member (not shown). 15
is an excitation coil built into the stator 15 and wound annularly; 16 is a bearing installed between the shaft 4 and the stator 14;
7, 18, and 19.

Here, the method of integrally fixing the connecting member 2 to the drive member 1 during die-casting of the drive member 1 will be described with reference to FIGS. 2 to 4. In each figure, reference numeral 20 denotes a connecting material showing the shape of the connecting member 2 before formation, and although not shown in FIG. An annular protrusion 20b is formed at the center of the inner peripheral portion, which is important for performing a positioning function during molding, which will be described later. 21 and 22 are drive members 1
The lower mold 21 has a fitting part 21a into which the annular protrusion 20b of the connecting material 20 fits and positions the connecting material 20 at a fixed position on the lower mold 21. The upper mold 22 moves in the direction of the arrow.

To manufacture the drive member 1 including the connecting member 2, first, the annular protrusion 20b of the connecting material 20 is fitted into the fitting part 21b of the lower mold 21, and the connecting material 20 is positioned at a fixed position on the lower mold 21. , then the upper mold 22
are combined with the lower mold 21 to form a space 23, and molten aluminum is forced into the space 23 between the upper and lower molds 21 and 22 and hardened. At this time,
The molten aluminum penetrates into the uneven portion 20a on the outer periphery of the connecting material 20 and hardens while surrounding the entire periphery of the connecting material 20. Therefore, upper and lower type 2
The drive member material 24 integrally fixed with the connection material 20 is taken out from 1 and 22, and the inner peripheral side of the die-cast drive member material 24 is cut to the dotted lines A and B shown in FIG. When the first connecting surface 2a of the connecting member 2 is exposed to the inner peripheral side, the manufacture of the drive member 1 in which the connecting member 2 is integrally fixed as shown in FIG. 1 is completed. In this way, the connecting member 2 can be integrally fixed with the drive member 1 during die-casting of the drive member 1, making manufacturing easy, and since the drive member 1 and the connecting member 2 are firmly connected via the uneven portion 20a. Movement of the connecting member 2 in the axial and circumferential directions with respect to the drive member 1 can be reliably prevented, and the connecting operation described below can be stabilized.

The operation of the embodiment configured as above will be explained. When the drive member 1 is being rotated by the drive source, when the exciting coil 15 is energized and energized, the magnetic flux Φ is transmitted to the stator 14 - one magnetic pole 14a - one connecting part 5b - magnetic particles 7 - as shown by the dotted line in the figure. The connection member 2 - the magnetic particles 7 - the other connection part 5b - the other magnetic pole 14a - the stator 14 are passed through. Due to the electromagnetic force based on this magnetic flux Φ, the first and second connecting surfaces 2a,
The magnetic particles 7 between 5a are bonded together to form the connecting member 2.
Torque is transmitted from drive member 1 to driven member 5 to connect connection 5b. Conversely, when the excitation coil 15 is deenergized, the magnetic flux Φ disappears and the connection between the connecting member 2 and the connecting portion 5b by the magnetic particles 7 is released, so that the torque transmission from the drive member 1 to the driven member 5 is stopped. When the excitation coil 15 is deenergized, the magnetic particles 7 are attached to the drive member 1
The idling torque on the driven member 5 is Almost no occurrence occurs, so the responsiveness of torque transmission is extremely stable and rapid. In addition, this prevents the irregular movement of the magnetic particles 7 during idle rotation, making it possible to reduce wear caused by collisions, rubbing, etc. between the magnetic particles 7 during idle rotation, and thus extending the service life. . What is important for achieving the above-mentioned effects is the connection member 2 and the connection part 5b.
This is to locate the connecting operation part with the outermost periphery.

Further, the connecting member 2 located at the outermost periphery and made of a magnetic material such as iron material is made to face only the second connecting surface 5a of the connecting portion 5b of the driven member 5, and forms a magnetic circuit in order to obtain the necessary connecting torque. A structure in which the connecting member 2 is supported by the drive member 1 made of a non-magnetic material such as aluminum so that the first connecting surface 2a is exposed on the inner periphery, that is, only a necessary part on the magnetic circuit. By arranging the connecting member 2, the magnetic flux Φ flows only through the connecting member 2 from the connecting part 5b of the driven member 5, and leakage of the magnetic flux Φ to other than the connecting member 2 can be minimized. The magnetic circuit can be constructed with high efficiency, and since almost all of the magnetic flux Φ acts on the magnetic particles 7, the connecting portion 5b, and the connecting member 2, the connecting torque is significantly improved.

In addition, by locating the connecting part between the connecting member 2 and the connecting part 5b at the outermost periphery and fixing the connecting member 2 integrally with the drive member 1 during aluminum die-casting of the drive member 1, it is possible to prevent the occurrence of problems in the connecting part. The generated heat is conducted through the drive member 1, which has high thermal conductivity and is exposed on the outer periphery, and is dissipated into the outer periphery atmosphere, resulting in efficient heat dissipation, that is, improved cooling efficiency, and prevents the burning of magnetic particles 7, etc. Deterioration can be reduced and stable connection operation can be obtained. Furthermore, by forming the uneven portion 20a on the outer circumference of the connecting member 2, the heat dissipation area of the connecting member 2 is increased, so that the heat dissipation efficiency is further improved.

In addition, a stator 15 having a built-in excitation coil 15 is provided.
The average winding diameter of the excitation coil 15 can be made small by arranging it on the inner circumferential side of the connecting operation part between the connecting member 2 and the connecting part 5b, and the ampere turns become large because it is inversely proportional to the average winding diameter of the coil. Even with a small average winding diameter, the increase in ampere turns can be measured. This is because if the same ampere turns are set, it is possible to wind a winding with a smaller wire diameter, reducing the weight of the winding of the excitation coil 15, and at the same time reducing the outer diameter of the stator 14. Can be manufactured small and inexpensively.

In addition, in the case of a magnetic particle type electromagnetic coupling device, the transmitted torque is proportional to the axial width and the square of the diameter of the coupling operation part, and this means that when the coupling operation part is located at the outermost periphery as in this embodiment, By arranging the stator 14 containing the excitation coil 15 on the inner circumferential surface of the connecting portion, there will be no extra parts other than the stator 14, which is indispensable for the connecting portion, within the volume determined by the connecting portion. Therefore, a magnetic particle type electromagnetic coupling device can be manufactured with minimum space and weight. Furthermore, with the above-described structure, the number of parts can be reduced, the shape of the parts can be simple, the yield can be improved, and the product can be easily manufactured at low cost.

Furthermore, if the drive member 1 is manufactured by aluminum die-casting, the work such as painting the drive member 1 can be omitted since aluminum has a rust-preventing effect. Furthermore, if the drive member 1 including the connecting member 2 is made of aluminum, the weight can be significantly reduced compared to the case where the drive member 1 is made of iron or the like, and a lightweight connecting device can be obtained.

Although the above embodiment has been described as a clutch device, it can also be applied as a brake device by fixing either the drive or driven members 1 and 5.

As described above, the present invention provides a connection operation section by locating the connection operation section between the connection member and the second connection main body at the outermost periphery, and arranging a magnetic device having an excitation coil on the inner circumference side of the connection operation section. The generated heat is efficiently dissipated into the outer atmosphere through the connecting member and the first connecting body that integrally fixes the connecting member,
Deterioration such as the seizure phenomenon of magnetic particles can be reduced, stable connection operation can be obtained, and the service life can be extended. Moreover, the connecting member is formed of a magnetic material and arranged in a necessary part on the magnetic circuit corresponding to the connecting operation part, and the first connecting body is made of a non-magnetic material and an aluminum material with a high heat transfer coefficient. The first
By supporting the connecting body, the above-mentioned heat dissipation efficiency can be further improved, and the magnetic flux from the excitation coil is concentratedly passed through the connecting member without leaking to the supporting member, etc., which improves the stability of the connecting torque. Excellent effects can be obtained, such as improved responsiveness and an increase in ampere turns due to a reduction in the average winding diameter of the excitation coil, which together with an increase in connection torque can be measured.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part showing an embodiment of the present invention, FIG. 2 is a sectional view of a main part showing a connecting material 20, and FIG. 3 is a dry member material 24 including the connecting material 20.
FIG. 4 is a cross-sectional view showing the drive member material 24 after die-casting. In the figure, 1 is a drive member, 2 is a connecting member, 2a is a first connecting surface, 4 is a shaft, 5 is a driven member, 5a is a second connecting surface, 5b is a connecting portion,
6 is a non-magnetic member, 7 is a magnetic particle, 8 and 9 are labyrinths, 10 is a cover, 11 and 16 are bearings,
14 is a stator, 14a is a magnetic pole, 15 is an exciting coil, g is an annular hole, 20 is a connecting material, 20a is an uneven portion, 20b is an annular protrusion, 21 is a lower mold, 21a is a fitting portion, 22 is an upper mold , 23 is a space, and 24 is a drive member material. Note that the same reference numerals in each figure indicate the same parts.

Claims (1)

[Scope of Claims] 1. A first connecting body formed of an aluminum material, a connecting member formed of a magnetic material and integrally fixed to the first connecting body and exposing a first connecting surface on the inner periphery, A second connecting body having a second connecting surface facing the inner peripheral side of the first connecting surface with a gap therebetween and formed of a magnetic material, magnetic particles sealed in the gap,
and an excitation coil disposed on the inner circumferential side of the second connection main body, which causes magnetic flux to flow through the connection member and the second connection main body to magnetize the magnetic particles, the first and second connection main bodies. A magnetic particle type electromagnetic coupling device equipped with a magnetic device that controls the coupling. 2. The magnetic particle type electromagnetic coupling device according to claim 1, wherein the first coupling body is made of aluminum alloy casting. 3. The magnetic particle type electromagnetic coupling device according to claim 2, characterized in that the outer periphery of the coupling member is formed with irregularities.