JPS6119216Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a magnetic particle type electromagnetic coupling device having a structure in which a coupling operation section between a coupling member and a second coupling main body is arranged on the outer circumference side, and a magnetic device is arranged on the inner circumference side of the coupling operation section. Regarding.

As a conventional side of this type, 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 enclosed in the gap between the driven part and the drive part and in the gap 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 voids are arranged in double radial direction,
In addition, since the structure has interconnected voids, it is difficult to uniformly disperse the magnetic particles in each void.
This method has drawbacks such as different connection torques occurring at the inner and outer connecting portions and poor responsiveness.

In order to eliminate each of the above-mentioned drawbacks, this invention improves connection performance by arranging the connecting part between the connecting member and the second connecting body on the outer periphery of the magnetic device, thereby efficiently dissipating the heat generated in the connecting part. At the same time, the connecting member is formed in a shape along the flow direction of the magnetic flux flowing through the connecting member to form an effective magnetic path for the magnetic flux, and the purpose is to reduce the size and weight of the connecting member. The present invention provides a type electromagnetic coupling device.

The embodiment shown in FIGS. 1 and 2 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 from a non-magnetic material such as aluminum. Reference numeral 2 denotes a connecting member having a first connecting surface 2a on the inner periphery, which is made of a magnetic material such as iron and has a cylindrical shape, and has a shape along the flow direction of the magnetic flux φ, which will be described later, that is, a trapezoidal cross section as shown in FIG. The connecting member 2 is integrally connected to the drive member 1 during die-casting of the drive member 1 described above, and only the first connecting surface 2a is exposed on the inner periphery. Furthermore, the first
The connecting surface 1a corresponds to the bottom of the trapezoid. 4 is a shaft connected to a load side (not shown); 5 is a first connecting surface 2a of the connecting member 2 fixed to the shaft 4;
A driven member that is a second connection main body, which 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 gap g on the radially inner circumferential side of the drive member, and formed in a bowl shape from a magnetic material such as iron material has been done. 6 is an annular non-magnetic member that magnetically divides the connecting portion 5b of the driven member 5 into two; 7 is a magnetic particle sealed in a single annular gap g; 8 and 9 are the driven members 5;
A labyrinth 10 is fixed to the right side opening of the drive member 1 and cooperates with the labyrinth 9 to prevent the magnetic particles 7 from falling out of the single annular gap g. A dustproof cover 11 having a labyrinth function to prevent falling from a single annular gap g is a bearing installed between the drive member 1 and the shaft 4, and is positioned by snap springs 12 and 13. Reference numeral 14 denotes a pair of annular magnetic poles 14a that are installed on the radially inner circumferential side of the coupling operation portion between the coupling member 2 and the coupling portion 5b, and are opposed to the radially inner circumferential side of the divided coupling portion 5b with a gap therebetween. The stator is made of a magnetic material, such as iron, and is prevented from rotating by a rotation stopper (not shown). Reference numeral 15 denotes an excitation coil which is built into the stator 14 and is wound annularly, and together with the stator 14 constitutes a magnetic device. 16 is a bearing installed between the shaft 4 and the stator 14,
It is positioned by snap springs 17, 18, and 19.

Next, the operation 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 transferred from the stator 14 to one of the magnetic poles 14a to one of the connecting portions 5b to the magnetic particles as shown by the protruding line in the figure. 7-Connection member 2-Magnetic particle 7-Other connection portion 5b-Other magnetic pole 14a-Stator 1
4 is passed through. Due to the electromagnetic force based on this magnetic flux φ, the magnetic particles 7 between the first and second connecting surfaces 2a and 5a are combined in a chain shape to connect the connecting member 2 and the connecting portion 5b, thereby transmitting torque from the drive member 1 to the driven member 5. will be carried out. Conversely, if the excitation coil 15 is deenergized, the magnetic flux φ disappears, and the connection between the connecting member 2 and the connecting part 5b by the magnetic particles 7 is released, so the torque transmission from the drive member 1 to the driven member 5 is stopped. .

Here, considering the magnetic flux φ flowing through the connecting member 2 and the connecting portion 5b, which is important for the transmitted torque,
The axial width of the connecting member 2 and the connecting portion 5b and the first and second
The diameters of the connecting surfaces 1a, 5a are determined by the necessary transmission torque, and the radial thickness (1) of the center portion A of the connecting member 2 is determined by the cross-sectional area of the magnetic path required for the magnetic flux φ to flow therethrough. When the connecting member 2 is formed into a cylindrical shape with a rectangular cross section as shown in FIG. Since the magnetic flux φ does not flow, the outer peripheral sides B on both sides of the connecting member 2 become useless portions without contributing to the flow of the magnetic flux φ.

Therefore, in this embodiment, as shown in FIG. 4, the connecting member 2 has a shape along the flow direction of the magnetic flux φ, that is, a cylindrical shape with the portion B that does not contribute to the flow of the magnetic flux φ removed, and By forming the connecting member 2 into a shape, the magnetic flux φ determined by the magnetic path cross-sectional area of the central portion A
All the fluids can be effectively passed through without being obstructed, and as a result, the connecting member 2 can be made small, lightweight, and inexpensive.

Furthermore, this embodiment provides the following features. First, the connecting member 2, which is located on the outermost periphery and has a trapezoidal cross section and is made of a magnetic material such as iron, is placed so as to face only the second connecting surface 5a of the connecting portion 5b of the driven member 5, and is made of magnetic material to obtain the necessary transmission torque. A structure in which the connecting member 2 is formed into a trapezoidal cross-sectional shape corresponding to the road cross-sectional area and is fixed to the drive member 1 made of a non-magnetic material such as aluminum such that the first connecting surface 2a is exposed on the inner periphery, that is, a magnetic circuit. By arranging the connecting member 2 only in the necessary parts on the top,
Since the magnetic flux φ flows only through the connecting member 2 from the connecting portion 5b of the driven member 5, the leakage of the magnetic flux φ to areas other than the connecting member 2 can be extremely reduced, and an efficient magnetic circuit can be constructed, and the magnetic flux φ is approximately Since all of these act 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 by 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 made of aluminum, which has high thermal conductivity, and is dissipated into the surrounding atmosphere, resulting in efficient heat dissipation, that is, improved cooling efficiency. By forming the first part of the connecting member 2 into the shape
The heat conduction distance from the connecting surface 2a to the drive member 1 can be shortened, and the cooling efficiency of the connecting operation part can be further improved.Therefore, deterioration such as the seizure phenomenon of the magnetic particles 7 can be reduced, and stable connecting operation can be obtained.

In addition, a stator 14 having a built-in excitation coil 15 is also 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 circumference side of the coupling operation section, there will be no extra parts in the volume defined by the coupling operation section other than the stator 14, which is essential for performing the coupling operation. 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.

Note that the connecting member 2 is not limited to a trapezoidal cross section, and may have other shapes along the direction of magnetic flux flow.
For example, as shown in FIG. 5, the cross section with the first connecting surface 2a as the base is triangular, or as shown in FIG. is obtained.

Furthermore, although the above embodiments have been described as clutch devices, the present invention can also be applied as a brake device by fixing either the drive or driven members 1 and 5.

As described above, this invention locates the connecting part between the connecting member and the second connecting body at the outermost periphery, and arranges a stator equipped with an excitation coil on the inner circumferential side of the connecting part. The heat generated is generated by the connecting member and the first
It is efficiently dissipated into the surrounding atmosphere through the connecting body, reducing deterioration such as the burning phenomenon of magnetic particles.
This allows for stable connection operation and extended service life. In addition, by positioning the connecting member at a necessary part on the magnetic circuit corresponding to the connecting operation part and forming it from a magnetic material in a shape along the flow direction of the magnetic flux, the connecting member forms an effective magnetic path for the magnetic flux. However, the connecting member can be made smaller and lighter, and the magnetic flux can be concentrated in the connecting member without leaking to the first connecting body, etc., and the average winding diameter of the excitation coil is smaller, resulting in an increase in ampere turns. In combination with this, excellent effects such as an increase in connection torque can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a main part showing an embodiment of this invention, Fig. 2 is a sectional view of a main part showing a connecting member 2, and Fig. 3 is a sectional view of a main part showing an embodiment of this invention.
4 are configuration diagrams showing the magnetic flux φ flowing through the connecting member 2, and FIGS. 5 and 6 are main part sectional views showing other examples of the connecting member 2. In the figure, 1... Drive member, 2... Connecting member, 2a... First connecting body, 4... Shaft,
5... Driven member, 5a... Second connection surface, 5
b...Connecting portion, 6...Nonmagnetic member, 7...Magnetic particles, 8, 9...Labyrinth, 10...Cover, 1
1, 16...Bearing, 14...Suchita, 1
4a...magnetic pole, 15...excitation coil, g...annular gap. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims for Utility Model Registration] (1) A first connecting body formed of a non-magnetic material, a connection fixed to the first connecting body, having a first connecting surface on the inner periphery, and formed of a magnetic material. a second connecting body formed of a magnetic material and having a second connecting surface facing the inner peripheral side of the first connecting surface with a gap therebetween; magnetic particles sealed in the gap;
and a magnetic device that magnetizes the magnetic particles by passing a magnetic flux through the connecting member disposed on the inner peripheral side of the second connecting body and the second connecting body, and connects the first and second connecting bodies. A magnetic particle type electromagnetic coupling device, characterized in that the coupling member is formed in a shape along the flow direction of the magnetic flux flowing through the coupling member. (2) The magnetic particle type electromagnetic coupling device according to claim 1, wherein the coupling member has a trapezoidal cross section with the first coupling surface as the bottom. (3) The magnetic particle type electromagnetic coupling device according to claim 1, wherein the coupling member has a triangular cross section with the first coupling surface as the base.