JPH04165126A - Magnetic particle type electromagnetic coupling device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention is based on the following aspects: 1. The present invention relates to a magnetic particle type electromagnetic coupling device that controls the bonding force between second coupling entities by magnetization of magnetic particles.

[Conventional technology]

FIG. 2 shows a conventional electromagnetic coupling device of this type. In the figure, 1 is a drive member which is the first connection main body, 2 is an annular excitation coil built into this drive member 1 and supplied with power by a slip ring, brush, etc. (not shown), and 3a and 3b are on both sides of the drive member 1. The drive member 1 is fixed by bolts or the like, and a bracket connected to the input side (not shown) rotatably supports the output shaft 5 via bearings 4a and 4b, respectively. 6a.

6b is each bearing 4. a, arranged near 4h,
A sealing material 7 for preventing magnetic particles 8, which will be described later, from entering the bearings 4a and 4b is a driven member that is a second main body of connection, and is fixed to the output shaft 5. 8 is a magnetic particle 9a enclosed in a cylindrical gap formed between the inside of the drive member 1 and the outside of the driven member 7;
9b are each fixed to the side surface of the driven member 7 to hold the magnetic particles 8 as close to the connecting surface (operating surface) as possible,
This is a labyrinth provided to reduce intrusion into the sealing materials 6a and 6b. The material of live member 1 to driven member 7 is low carbon steel (S) with excellent magnetic properties.
IOC) is used.

Next, the operation will be explained. It is assumed that the input side bracket 3a or 3b coupled to a drive source (not shown) is rotated, and the drive member 1 is also rotated. At this time, if the excitation coil 2 is not excited, the magnetic particles 8 will be pushed against the operating surface of the drive member 1 by centrifugal force, and the dry line member 1 and the driven member 7 will not be connected. Here, when the excitation coil 2 is excited by a power supply device (not shown), the second
A magnetic flux Φ as shown by the broken line in the figure is generated, and the magnetic particles 8 that are part of this magnetic path are coupled in a chain between the drive member 1 and the driven member 7, and the driven member 7 is connected to the output shaft 5. They are connected together to transmit transmission torque, and the output side is driven. Next, when the excitation is cut off, drive member 1. Since the material of the driven member is made of low carbon steel (SIOC) with low residual magnetism, all the magnetic flux Φ is cut off, and the magnetic particles 8 are again pressed against the operating surface of the drive member 1 by centrifugal force. By controlling the excitation current in this manner, the torque can be controlled, and it has the advantage that it can be used in a connected sliding state when the temperature is raised to an allowable temperature.

[Invention or problem to be solved]

The conventional magnetic particle type electromagnetic coupling device is constructed as shown below. Here, the magnetic particle-f-8 has an air gap (hereinafter referred to as Normal l-lux can only be transmitted if it is evenly distributed in the powder gap (called the powder gap). By the way, in order to uniformly distribute the magnetic particles 8 in the powder gap, this device must be used in a horizontal position as shown in Figure 2.If it is used tilted, it will not be energized in the non-excited state as shown in Figure 3. The magnetic particles 8 come to be distributed in the horizontal part of the powder gap due to gravity. When the magnetic flux Φ is generated by excitation in this state, some magnetic particles enter the powder gap along the magnetic flux and transmit 1 to 1 lux, but due to the influence of gravity, they remain distributed next to the powder gap. Because there are also magnetic particles, all the magnetic particles are not uniformly distributed throughout the powder gap, which results in a low transmission
There was also the problem of instability.

This invention was made to solve the above-mentioned problems, and the purpose is to maintain the magnetic particles in the powder gap even when the device is used at an angle, and to obtain the same torque performance as when installed horizontally. do.

[Means to solve the problem]

The magnetic particle type electromagnetic coupling device according to the present invention has first and second
At least one of the connecting main materials is made of alloy steel containing 0.25% by weight or more of carbon, and the surface of the steel is hardened.

[Effect]

First in this invention. C which is the material of the second connecting body
Steel with a weight of 0.25% or more has a large residual magnetic property, so even if the excitation is turned off, magnetism remains inside the material, so the powder distributed in the -degree powder cap is tilted. Even if the powder is poured, it will not flow to the side of the powder gap and will be held in place.

〔Example〕

An embodiment of the present invention shown in FIG. 1 will be described below. In FIG. 1, the configuration is almost the same as that of the conventional device shown in FIG. The main material of the second connection is high carbon steel (34,8C), and its surface is hardened by induction hardening. That is, 1 is a drive member, and 7 is a driven member, each of which is made of carbon steel for mechanical structure containing 0.48% by weight of carbon. Ia and 7a are hardened layers with a thickness of 5
It weighs about 0 weight and has a surface hardness of Hv800 to 900.

Next, the operation of the above configuration will be explained.

When the drive member 1 is rotated in a horizontally mounted state and the magnetic particles 8 are excited once with them uniformly distributed within the powder gap, a magnetic flux Φ as shown by the broken line in Fig. 1 is generated, which is different from the conventional device. The same torque will be transmitted. Next, when the excitation is turned off, drive member 1. Since the material of the driven member 7 is high carbon steel (348C), residual magnetism remains inside the material, and therefore the magnetic particles 8 are held as they are within the powder gap without being affected by centrifugal force.

In this way, if the magnetic particles 8 are distributed in the powder gap by excitation in the horizontal mounting state, the magnetic particles 8 will remain on the operating surface even if the device is tilted due to the influence of residual magnetism. has been done.

Also, drive member 1. Since the surface (torque connection surface) of the driven member 7 is hardened by induction hardening, the drive member 1. In the process of connecting the driven member 7 and the magnetic particles 8, the magnetic particles 8 always connect to the drive member 1. This prevents wear and tear on the torque connecting surface, which occurs due to repeated friction with the torque connecting surface of the driven men's huff.

Note that in the above embodiment, drive member 1. Although 848C is shown as the material for the driven member 7, any material containing C: 0.25% by weight or more may be used.
Although induction hardening is shown as the surface hardening treatment for the driven member 7, other surface hardening treatments (flame hardening, nitriding, etc.) can also produce the same effects as in the above embodiment. Furthermore, in the above embodiment,
Although the description has been made regarding the clutch device of the magnetic particle type electromagnetic coupling device, it is also applicable to the brake device.

〔Effect of the invention〕

As described above, according to the present invention, since the material of the drive member and driven member is high carbon steel, if the magnetic particles are distributed in the powder gap by excitation in a - degree horizontal state, then residual magnetism will take over. Even when the device is tilted, the magnetic particles are always held within the powder gap, and when mounted horizontally, it is possible to obtain stable torque, which means that in the past, the range of use for mounting was limited depending on the situation. This has the effect of expanding. In addition, conventionally, low carbon steel was used for drive members and driven members, so hard chrome plating was used because it could not be hardened when surface hardening was applied, but this process was very expensive and required equipment. However, in the present invention, since high carbon steel is used, it can be hardened, so surface hardening can be done at a low cost.
This has the effect of improving the durability of the device.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing a magnetic particle type electromagnetic coupling clutch device according to an embodiment of the present invention, Fig. 2 is a sectional view showing a conventional magnetic particle type electromagnetic coupling clutch device, and Fig. 3 is a sectional view showing a conventional magnetic particle type electromagnetic coupling clutch device. FIG. 6 is a cross-sectional view showing the state of magnetic particle distribution when the electromagnetic coupling clutch device is installed tilted. In the figure, 1 is a drive member, 7 is a driven member, 8 is a magnetic particle, la, ? a is a hardened layer. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] A first connection main body (rotation drive member) and a second connection main body (rotation drive member) made of a magnetic material are opposed to each other through a gap, a magnetic field is formed in the gap, and magnetic particles are interposed in the gap. By magnetizing the first connecting body and the second
In a magnetic particle type electromagnetic coupling device that transmits torque on the driving side to the driven side by coupling the coupling bodies of the first and second coupling bodies with the magnetic particles, the material of at least one of the first and second coupling bodies is made of C. : A magnetic particle type electromagnetic coupling device characterized in that it is made of alloy steel containing 0.25% by weight or more, and its surface is hardened.