JPH1047390A - Electromagnetic connecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve heat resistance and wear resistance of a torque transmis sion part without causing cost increase and realize creep function at the demag netization of an exciting coil by providing cemented layers at the respective surface of first and second action faces. SOLUTION: A cemented layer 30 is provided at the surface of a first action face 2a, and a cemented layer 40 is provided at the surface of a second action face 12a. The respective cemented layers 30, 40 are formed of high carbon steel with a thickness of several hundreds and formed by cementation treatment to the surface of the respective action faces 2a, 12a. In this case, the carbon quantity of magnetic powder 14 is higher than conventional 0.02% and is set to 0.1-0.6%, for instance. The cemented layers 30, 40 are higher in hardness and residual magnetic flux density than the material (S10C) of base material 2, 12, and also the magnetic grain 14 is higher in hardness and residual magnetic flux density than the conventional one.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic coupling device used for transmitting a torque of, for example, a powder clutch for an automobile. The present invention relates to an electromagnetic coupling device that enables relatively small torque transmission (creep) even when the power is on.

[0002]

2. Description of the Related Art FIG. 3 is a side sectional view showing a conventional coiled magnetic particle type electromagnetic coupling device. In the figure, reference numerals 1 and 2 denote a pair of first base materials driven by an engine output shaft, and a highly permeable metal such as iron (carbon content 0.1%).
S10C, etc.), and constitutes a ring-shaped connection main body.

The inner first base material 2 has a ring-shaped recess formed in the center on the outer peripheral side, and is integrally press-fitted and fixed in the outer first base material 1. Reference numeral 2a denotes an operation surface (first operation surface) of the first base material 2 facing the second base material (described later), and the surface is chrome-plated.

[0004] Reference numeral 3 denotes a plate assembly integrally joined to the side of the inner first base material 2 by molding, and 4 denotes a plate assembly 3.
This is a cylindrical boss that is fixed by swaging. At the center of the boss 4, a spline for a hole is formed. Reference numeral 5 denotes a bracket that covers the outer side surfaces of the first base materials 1 and 2, 5 a denotes a fin for heat dissipation formed on the bracket 5, and 6 denotes a screw that fixes the bracket 5 to the side surface of the first base materials 1 and 2. .

[0005] 7 is an exciting coil wound in the concave portion of the first base material 2, φ is a magnetic flux generated by energizing the exciting coil 7,
Reference numeral 8 denotes a bobbin made of synthetic resin interposed between the concave portion and the exciting coil 7, 8a denotes a flange protruding from one end of the bobbin 8, and 8b denotes a terminal block integrally formed in the flange 8a. Although only one terminal block 8b is shown here, it is actually composed of a pair of terminal blocks.

Reference numeral 9 denotes a space in a concave portion formed above the excitation coil 7, and reference numeral 10 denotes a resin that fills the space 9 and fixes the excitation coil 7. Reference numerals 11 and 12 denote a pair of second base materials disposed inside the first base material 2 so as to be opposed to each other.
And are integrally joined by welding.

[0007] Reference numeral 12a denotes a second operation surface facing the first operation surface 2a.
This is the operation surface (second operation surface) of the base material 12, and the surface is plated with chrome. Reference numeral 13 denotes a bearing that supports the inner second base material 11 and the bracket 5. The bracket 5 supports the inner second base material 11.

[0008] g is the first operating surface 2a and the second operating surface 12
An annular gap 14 formed between the magnetic particles a and the magnetic particles sealed in the annular gap g. Reference numeral 15 denotes a driven shaft that is integral with the second base material 11, and has a spline for a hole formed in the inner peripheral portion. Reference numeral 16 denotes a pin for engaging the driven shaft 15 with the second base material 12.

Reference numeral 17 denotes a fixing plate fixed to the side of the bracket 5 via screws 18, reference numeral 19 denotes a slip ring assembly fixed to the fixing plate 17 via screws 18, and reference numeral 19a denotes a slip ring assembly 19 and terminals. A lead terminal 20 electrically connects the base 8b, and a screw 20 fixes the lead terminal 19a to the terminal base 8b. The slip ring assembly 19 is always supplied with power from brushes (not shown) that are in opposing contact.

Reference numeral 21 denotes a drive plate integrated with the first base materials 1 and 2, and reference numeral 22 denotes a screw for fixing the drive plate 21 to the first base material 1. Reference numeral 24 denotes a drive shaft from an external engine (not shown), which is fixed to the drive plate 21 via screws 23.

Reference numeral 25 denotes a spline shaft for driving an oil pump (not shown).
The boss 4 is spline-connected to the boss 4 positioned in the drive shaft 24 integrated with the boss 4. Reference numeral 26 denotes a spline shaft for a shaft connected to the driven shaft 15, which concentrically supports the spline shaft 25 on the inner peripheral portion of the cylinder.

Next, the operation of the conventional electromagnetic coupling device shown in FIG. 3 will be described. First, when power is supplied from a power supply (not shown), a current is supplied to the exciting coil 7 from the lead terminal 19a of the slip ring assembly 19 via the terminal block 8b, and the exciting coil 7 is excited.

Thus, the first base material 2 and the second base material 1
A magnetic flux φ (see a broken line) is generated in the space including the magnetic particles 2, and the magnetic particles 14 are solidified between the operation surfaces 2 a and 12 a. Therefore, the first base material 2 and the second base material 12 are connected via the magnetic particles 14, and the rotational torque of the first base material 2 is transmitted to the second base material 12 to drive the driven shaft 15 and the spline shaft. 26 is driven to rotate.

When the power supply to the exciting coil 7 is cut off (or reversely excited), the magnetic particles 14
The connection between the first base material 2 and the second base material 12 is released by being released from between a and 12a.

In recent years, in order to improve drivability, a creep function for maintaining a relatively small torque by maintaining a weak connection state has been required. However, the first base material 2 and the second base material are required. Due to the slip of the magnetic particles 14 on the sliding surfaces 12 (the respective operating surfaces 2a and 12a),
Wear and temperature rise may occur, and various inconveniences may occur.

In particular, the chromium plating applied to each of the operating surfaces 2a and 12a has a problem in heat resistance and abrasion resistance. When the temperature exceeds 400 ° C., a sharp decrease in hardness is caused.
As the wear progresses, normal torque transmission cannot be performed, and the device does not function as an electromagnetic coupling device.

Therefore, as disclosed in Japanese Utility Model Laid-Open No. 2-54932 or Japanese Utility Model Laid-Open No. 2-121634,
Electromagnetic coupling devices in which the wear resistance of each operating surface is improved have been proposed, but the materials used are expensive, and no consideration is given to increasing the residual magnetic flux density. Therefore, in order to realize the creep function, the amount of power supply to the exciting coil 7 must be controlled, which further increases the cost.

Further, as another example of the conventional electromagnetic coupling device, when the second base material is formed in a disk shape, another problem occurs. FIG. 4 is a side sectional view showing an example of a braking device in which the electromagnetic coupling device is a disk type, FIG. 5 is a front view showing sliding parts of each base material in FIG. 4, and FIG. 6 is an enlarged view of the sliding parts. 5 is a side sectional view, FIG. 5 shows a state at the time of stoppage, and FIG. 6 shows a state at the time of rotation. In each figure, 7, 13, 14, 24, g and φ are the same as described above.

Reference numeral 110 denotes a stator constituting the first base material, 1
10a is an operation surface (first operation surface) of the stator 110, 1
11 is a stator 11 provided on the first operating surface 110a.
Reference numeral 120 denotes a rotor constituting the second base material, and 120a denotes an operation surface (second operation surface) located on a side surface of the rotor 120.

In FIG. 5, the arrow shown by a solid line is the direction of rotation of the rotor 120, and the arrow shown by a broken line is the magnetic particles 14.
Is the moving direction. In this case, the drive shaft 24 is formed integrally with the second base material, that is, the rotor 120.

Next, the operation of the conventional disk type electromagnetic coupling device will be described with reference to FIGS. When the rotor 120 is rotated by the rotation of the drive shaft 24, the magnetic particles 14 stored in the outer peripheral portion of the rotor 120 are rotated.
Move as shown by the broken line in FIG. 5 and are diffused to the outer periphery by centrifugal force.

Here, when the exciting coil 7 is energized, the magnetic particles 14 solidify between the operating surfaces 110a and 120a, and connect the rotor 120 to the stator 110 to brake the drive shaft 24.

However, when the centrifugal force acts during rotation, particularly when the rotor 120 has a disk shape, the magnetic particles 14 are pressed against the inner surface of the non-magnetic ring 111 in the first operating surface 110a as shown in FIG. So rotor 1
20 may be locked to the stator 110 and the braking state may not be released.

[0024]

As described above, in the conventional electromagnetic coupling device, in the configuration example of FIG. 3, the operating surfaces 2a and 12a are plated with chromium, but the heat resistance and the wear resistance are low. Therefore, there is a problem in that it is liable to deteriorate due to wear, and may not be able to function as an electromagnetic coupling device when used for a long time.

Therefore, there is a problem that even if an attempt is made to realize the creep function, it cannot be realized due to the strength of the operating surfaces 2a and 12a. Further, for example, if the excitation coil 7 is weakly excited in order to realize the creep function, there is a problem that the power supply circuit becomes complicated and the cost increases.

Further, in the configuration example shown in FIG. 4, in addition to the above-described problems, there is a possibility that the magnetic particles 14 lock the rotor 120 (second base material) due to centrifugal force and cannot function as an electromagnetic coupling device. There was a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and improves the heat resistance and abrasion resistance of the torque transmitting section without increasing the cost, and at the time of deenergizing the exciting coil. It is another object of the present invention to obtain an electromagnetic coupling device that enables relatively small torque transmission (creep).

[0028]

An electromagnetic coupling device according to a first aspect of the present invention includes an annular first base material having a first operating surface, and a second operating surface opposed to the first operating surface. And a magnetic particle interposed between the first and second operating surfaces, and an annular exciting coil buried in the first base material, when power is supplied to the exciting coil. In an electromagnetic coupling device for connecting a first base material and a second base material via magnetic particles, a carburized layer is provided on each of the first and second operating surfaces.

Further, according to a second aspect of the present invention, in the electromagnetic coupling device according to the first aspect, the carbon content of the magnetic particles is set to 0.1%.
% To 0.6%.

According to a third aspect of the present invention, there is provided an electromagnetic coupling device comprising: an annular first base material having a first operating surface;
A second base material having a second working surface facing the working surface of
Magnetic particles interposed between the first and second operation surfaces, and an annular exciting coil embedded in the first base material, wherein the first mother material is connected via the magnetic particles when power is supplied to the exciting coil. In the electromagnetic coupling device for coupling the material and the second base material, the carbon content of the magnetic particles is set to 0.1% to 0.6%.

According to a third aspect of the present invention, in the electromagnetic coupling device according to any one of the first to third aspects, the second base material is formed in a disk shape, and the side surface of the second base material is It constitutes a second operation surface.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an enlarged side sectional view showing a main part of the first embodiment of the present invention.
And 14 are the same as those described above (see FIG. 3). The configuration not shown is as shown in FIG.

Reference numeral 30 denotes a carburized layer provided on the surface of the first operating surface 2a, and reference numeral 40 denotes a carburized layer provided on the surface of the first operating surface 2a. Each carburized layer 30 and 40 has several hundred μ
Made of high carbon steel having a thickness of about
2a is formed by carburizing the surface.

In this case, the carbon content of the magnetic particles 14 is higher than the conventional value of about 0.02%, and is 0.1% to 0.1%.
It is set to 6%. The carburized layers 30 and 40 have higher hardness and residual magnetic flux density than the material of each of the base materials 2 and 12 (S10C). Similarly, magnetic particles 14 according to Embodiment 1 of the present invention have higher hardness and residual magnetic flux density than conventional ones.

Next, the operation according to the first embodiment of the present invention will be described with reference to FIGS. In addition,
The general operation is the same as described above, and will not be described here.

In this case, even if the excitation coil 7 in the first base material 2 is deenergized, the magnetic particles 14 and the carburized layers 30 and 4
0, the first base material 2 and the second base material 1
2 is maintained in a weak connection state. Therefore, relatively small torque transmission is automatically performed, and the creep function can be easily realized without increasing the cost.

At this time, the magnetic particles 14 made of high carbon steel
In addition, the carburized layers 30 and 40 have sufficient heat resistance and wear resistance and are hardly deteriorated by wear, so that the function as the electromagnetic coupling device is not impaired.

Further, since oxidation, fine powder and fine graining of the magnetic particles 14 are suppressed, torque transmission as an electromagnetic coupling device can be stabilized and the life of the device can be extended.

Embodiment 2 In the first embodiment, the carburized layers 30 and 40 are provided on each of the operating surfaces 2a and 12a.
And the magnetic particles 14 are made of high carbon steel, but the magnetic particles 14 similar to the conventional ones may be used only by providing the carburized layers 30 and 40. In this case, the magnetic particles 1
Although the strength of No. 4 cannot be improved, the wear resistance of the operating surfaces 2a and 12a is improved, and the creep function can be realized as described above.

Embodiment 3 Further, the magnetic particles 14 are only made of high carbon steel, and the carburized layers 30 and 40 need not be provided. In this case, although the strength of each of the operating surfaces 2a and 12a cannot be improved, the wear resistance of the magnetic particles 14 is improved and the creep function can be realized as described above.

Embodiment 4 FIG. Further, in the first embodiment, the case where the electromagnetic coupling device transmits the torque has been described. However, the electromagnetic coupling device may be a braking device or a disk type as shown in FIG.

FIG. 2 is a side sectional view showing a main part of a fourth embodiment of the present invention applied to a disk-type electromagnetic coupling device, wherein 14, 24, 110, 110a, 111, 120 and 120a are the same as those shown in FIG. 4).
The configuration not shown is as shown in FIG. 4 and FIG.

In this case, although not shown, each operating surface 110
The surfaces of a and 120a are provided with the same carburized layer as described above (see FIG. 1), and the magnetic particles 14 are made of high carbon steel.

As a result, even when the excitation coil 7 is deenergized, the magnetic flux remains in the magnetic particles 14 and the carburized layer.
4 is not pressed against the outer diameter. Therefore,
As shown in FIG. 2, since the magnetic particles 14 are held on the outer peripheral side surface of the second operation surface, the rotor 120 is not locked.

[0045]

As described above, according to the first aspect of the present invention, an annular first base material having a first operation surface and a second operation surface having a second operation surface opposed to the first operation surface are provided. 2 base materials and 1st
And a magnetic particle interposed between the second operating surfaces, and an annular exciting coil embedded in the first base material, and the first base material and the magnetic material are supplied via the magnetic particles when power is supplied to the exciting coil. In the electromagnetic coupling device for coupling the second base material, a carburized layer is provided on each of the first and second operating surfaces, so that the heat resistance and wear resistance of the torque transmitting unit are improved without increasing the cost. In addition, there is an effect that an electromagnetic coupling device that can realize a creep function when the excitation coil is deenergized is obtained.

According to a second aspect of the present invention, in the first aspect, the carbon content of the magnetic particles is 0.1% to 0.6%.
, The effect of obtaining an electromagnetic coupling device with further improved heat resistance and wear resistance of the magnetic particles is obtained.

According to a third aspect of the present invention, the first
An annular first base material having a first operating surface, a second base material having a second operating surface opposed to the first operating surface, and a magnetic material interposed between the first and second operating surfaces. An electromagnetic coupling device comprising: particles; and an annular excitation coil embedded in the first base material, wherein the first base material and the second base material are connected via the magnetic particles when power is supplied to the excitation coil. The carbon content is set to 0.1% to 0.6%, which improves the heat resistance and wear resistance of the torque transmission section without increasing the cost, and realizes the creep function when the excitation coil is deenergized. There is an effect that a possible electromagnetic coupling device is obtained.

According to a fourth aspect of the present invention, in any one of the first and second aspects, the second base material is formed in a disk shape, and the side surface of the second base material is the second base material. Since the operation surface is configured, there is an effect that an electromagnetic coupling device that does not cause a lock state can be further obtained.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a main part of a first embodiment of the present invention.

FIG. 2 is a side sectional view showing a main part of a second embodiment of the present invention.

FIG. 3 is a side sectional view showing a conventional electromagnetic coupling device.

FIG. 4 is a side sectional view showing a conventional disk-type electromagnetic coupling device.

FIG. 5 is a front view showing a main part in FIG. 4;

6 is an enlarged side sectional view showing a main part in FIG. 4;

[Explanation of symbols]

1, 2 first base material, 2a, 110a first operation surface, 7
Excitation coil, 12 second base material, 12a, 120a second
Operating surface, 14 magnetic particles, 30, 40 carburized layer, 11
0 Stator (first base material), 120 rotor (second base material).

Claims (4)

[Claims] An annular first base material having a first operating surface; and a second operating surface having a second operating surface opposed to the first operating surface.
A base material, magnetic particles interposed between the first and second operation surfaces, and an annular excitation coil embedded in the first base material, wherein the power supply to the excitation coil An electromagnetic coupling device that connects the first base material and the second base material via magnetic particles, wherein a carburized layer is provided on each of the first and second operating surfaces. . 2. The method according to claim 1, wherein the carbon content of the magnetic particles is 0.1% to 0.1%.
The electromagnetic coupling device according to claim 1, wherein the electromagnetic coupling device is set to 6%. 3. An annular first base material having a first operating surface, and a second operating surface having a second operating surface facing the first operating surface.
A base material, magnetic particles interposed between the first and second operation surfaces, and an annular excitation coil embedded in the first base material, wherein the power supply to the excitation coil An electromagnetic coupling device for coupling the first base material and the second base material via magnetic particles, wherein the carbon content of the magnetic particles is set to 0.1% to 0.6%. apparatus. 4. The apparatus according to claim 1, wherein the second base material has a disk shape, and a side surface of the second base material forms the second operation surface. An electromagnetic coupling device according to any one of the above.