JPH0118902Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a magnetic particle type electromagnetic clutch, and in particular to an electromagnetic clutch that can effectively prevent foreign matter from entering a gap formed between a driving member and a driven member. It's about clutches.

BACKGROUND OF THE INVENTION For example, it is known to provide a magnetic particle type electromagnetic clutch in order to transmit the rotation of an automobile engine to a transmission. One type of such electromagnetic clutch has a cylindrical driving member that is rotated around a center line, a cylindrical hub part that connects to the driven shaft in the center, and a cylindrical hub part that is concentric with the driving member. a driven member that is relatively rotatable at the drive member; and a driven member that is attached to both ends of the drive member and forms an annular space for accommodating magnetic particles together with the inner circumferential surface of the drive member and the outer circumferential surface of the driven member. Some devices include an annular labyrinth member. The rotational force of the driving member is transmitted to the driven member by magnetically coupling magnetic particles by excitation of an excitation coil in the gap between the inner circumferential surface of the driving member and the outer circumferential surface of the driven member. It is. Furthermore, the labyrinth member prevents the magnetic particles contained in the annular space from leaking out.

However, although conventional labyrinth members are effective in preventing magnetic particles from leaking out from the annular space to the inner circumference, objects moving from the inner circumference to the outer circumference of the clutch enter the annular space. The ability to prevent this from happening is low;
There was a risk that foreign matter generated inside the clutch and moving toward the outer periphery in accordance with the centrifugal force would enter the annular space in which the magnetic particles were accommodated. Such foreign objects include abrasion powder between the driven shaft and the driven shaft in the hub portion of the driven member, lubricating oil, oil, etc. filled in the hub, and the intrusion of such foreign objects into the annular space may cause damage to the magnetic particle type electromagnetic clutch. There was a risk that the power transmission performance of the engine would deteriorate.

Purpose of the invention The present invention was developed against the background of the above circumstances, and its purpose is to prevent foreign matter from penetrating into the annular space where magnetic particles are housed, even if foreign matter occurs inside the clutch. An object of the present invention is to provide a magnetic particle type electromagnetic clutch which can effectively prevent the above problems.

Structure of the Invention In order to achieve this object, in the present invention, an inner periphery of at least one of the labyrinth members attached to both ends of the driving member has an inner periphery that is connected to one end of the hub portion of the driven member. a first annular wall that is close to the outer circumferential surface; and a first annular wall that is located at a predetermined gap toward the other end of the hub part in the direction of the center line of the driven member, and that is located at the outer circumferential edge of the driven member; a second annular wall that forms an inward annular groove between the first annular wall and the first annular wall by being in close contact with the outer peripheral edge of the annular wall; A communicating discharge hole was formed.

Effects of the invention As described above, if an annular groove that opens in the inner circumferential portion of the labyrinth member near the outer circumferential surface of the hub portion of the driven member is formed by the first annular wall and the second annular wall, Even if foreign matter such as wear powder or oil moves from inside the hub portion to the outer circumferential side due to centrifugal force, the first annular wall prevents such foreign matter from entering the annular space. The particles are also received by an annular groove that opens close to the hub part, and are further discharged to the outside through a discharge hole formed in the first annular wall, so that foreign particles do not enter the annular space where the magnetic particles are accommodated. I won't. Therefore, it is effectively possible to prevent the torque transmission performance of the magnetic particle type electromagnetic clutch from being degraded due to the intrusion of foreign matter.

Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

The clutch shown in FIG. 1 is an automobile clutch, which is built into a clutch housing fixed to an engine (not shown), and which converts the rotation of the engine's crankshaft 10, which serves as a drive shaft (input shaft), to a driven shaft. It is used to transmit or cut off the signal to the output shaft 12.

A bottomed cylindrical flywheel 14 is fixed to the end of the crankshaft 10, and a first yoke member 1 is attached to the inner surface of the outer peripheral part of the flywheel 14.
6 and a second yoke member 18, a yoke 20 serving as a driving member is fixed. York 20
has a thick-walled cylindrical shape, and is equipped with an excitation coil 22 inside and an inner circumferential friction surface 24 on the inner circumferential surface. Furthermore, a front labyrinth member 26 and a rear labyrinth member 28 are fixed to the yoke 20, and the rear labyrinth member 28 is integrally provided with a cylindrical bearing case 30.

A ball bearing 32 is disposed within the bearing case 30, and a boss portion 36 of a rotor 34 is rotatably supported by this ball bearing 32. The rotor 34 is connected to the yoke 2
The outer friction surface 38 of the rotor 34 is provided concentrically and relatively rotatably with the yoke 20 inside the rotor 34.
faces the inner peripheral friction surface 24 with a minute gap 40 in between. A substantially closed annular space 42 is formed by the yoke 20, both labyrinth members 26 and 28, and the rotor 34, and a predetermined amount of magnetic powder 44 is enclosed in this annular space 42. The front labyrinth member 26 and the rear labyrinth member 28 have annular protrusions 46 and 48 that are very close to the rotor 34, and this proximity prevents the magnetic particles 44 from leaking out of the annular space 42. .

The rotor 34 is an annular member, and two plates 50 and 52 are fixed to the inside thereof by bolts. The elastic member 54 is held. On the other hand, a clutch hub 56 is attached to the end of the output shaft 12 by spline connection so as to be able to slide in the axial direction and not be able to rotate relative to the shaft.

The clutch hub 56 includes a cylindrical hub portion 58 into which the end of the output shaft 12 is fitted, and a disk portion 60 projecting in the form of a flange in the radial direction from an intermediate portion of the outer peripheral surface of the hub portion 58. A section 60 is disposed between the two plates 50 and 52 and is connected to the rotor 34 via an elastic member 54. The rotation of the rotor 34 is transmitted to the clutch hub 56 via the plates 50 and 52 and the elastic member 54, and the driven member includes the clutch hub 56, the plates 50 and 52, and the rotor 34. be.

A pump drive rod 62, one end of which is connected to the crankshaft 10, is inserted into the output shaft 12 so as to be relatively rotatable. and output shaft 12
An oil seal 66 is fitted into the open end from which the rod 64 protrudes, allowing relative rotation between the output shaft 12 and the rod 54 while preventing leakage of lubricating oil between the two. There is.

A slip ring 68 is fixed to the outer peripheral surface of the bearing case 30, and when this slip ring 68 comes into sliding contact with a brush (not shown), electric power is supplied to the excitation coil 22 via a conductive member 70 and a conductive wire 72. are now being supplied.

FIG. 2 shows an enlarged view of the vicinity of the front labyrinth member 26. Front labyrinth member 26
A first annular wall 74 is provided on the inner circumference of the labyrinth member 26 and extends toward the hub portion 58 . The first annular wall 74 is located at a position where the inner circumferential edge of the first annular wall 74 slightly enters the other end side of the opening edge of the hub portion 58 .
8 is placed close to the outer circumferential surface of one end thereof. Further, a second annular wall 76 is provided on the inner circumference of the front labyrinth member 26 adjacent to the first annular wall 74 . The second annular wall 76 is located at a predetermined distance from the first annular wall 74 toward the other end of the hub 58 in the direction of the center line of the hub 58, and has an inner peripheral edge that extends toward the other end of the hub 58. 58. The first annular wall 74 and the second annular wall 76 are brought into close contact with each other by a rivet 78 at the outer peripheral edge on the side far from the hub portion 58, and as a result, the first annular wall 74 and the second annular wall 76 An annular groove 80 that opens inward, in other words, toward the hub portion 58, is formed between the annular wall 76 and the annular wall 76 of the hub portion 58.

This annular groove 80 forms an annular space close to and surrounding the hub portion 58, while
A discharge hole 82 is formed in the first annular wall 74 at the bottom side of the annular groove 80, that is, at the outer peripheral side position, and this discharge hole 82 connects the annular groove 80 to the front labyrinth member 26 as shown in FIG. and communicates with a space 83 formed between the first annular wall 74 and the inner surface of the flywheel 14. Further, this space 83 is communicated with the outside of the clutch through a relief hole 84 formed in the flywheel 14.

A truncated conical shielding member 86 is fixed in the boss portion 36 of the rotor 34 on the rear labyrinth member 28 side, and the tapered tip edge (inner peripheral edge) of the shielding member 86 is fixed to the hub portion 58 . It is placed close to the outer peripheral surface of the end portion.

In the magnetic particle type electromagnetic clutch configured as described above, when excitation power is supplied to the excitation coil 22, magnetic particles 44 are generated in the gap 40 between the inner peripheral friction surface 24 of the yoke 20 and the outer peripheral friction surface 38 of the rotor 34. The rotation of the yoke 20 is transmitted to the rotor 34 by its magnetic coupling force and frictional force, and the output shaft 12 is further rotated via the clutch hub 56.

The space between the rod 62 and the output shaft 12 is sealed by an oil seal 66 to prevent lubricating oil from leaking out. However, if the oil seal 66 becomes old, the lubricating oil may leak out of the opening in the hub portion 58. It may ooze out from the inside to the outside. Such leaked oil moves outward due to centrifugal force, but if it enters the annular space 42 or gap 40 that houses the magnetic particles, it will significantly reduce the coefficient of friction of the magnetic particles, resulting in a decrease in torque transmission performance. Even if the excitation coil 22 is demagnetized,
Due to the viscosity of the oil, it becomes difficult for the magnetic particles filled in the gap 40 to come out of the gap 40 into the annular space 42, which may result in poor clutch disengagement.

However, in the magnetic particle type electromagnetic clutch of this embodiment, even if oil seeps out from the oil seal 66 and is scattered toward the outer periphery due to centrifugal force as shown by the arrow in FIG. First annular wall 7
It is blocked from entering the second annular wall 76 by the outer wall surface of No. 4, is collected at the outer periphery of the space 83 along the first annular wall 74, and escapes to the outside of the clutch through the escape hole 84. It will be done.

Additionally, oil adhering to the outer wall surface of the first annular wall 74 drips down when the engine is stopped and flows into the annular groove 80 from between the tip edge of the annular wall 74 and the outer peripheral surface of the hub portion 58 due to capillary action. Sometimes it gets in. However, even if a small amount of oil enters the annular groove 80, centrifugal force as the engine rotates causes such oil to flow through the first and second annular walls 74, 76 and to the bottom of the annular groove 80. The oil collected on the side is drained through the drain hole 8.
2 to the space 83, and further to the outside through the escape hole 84.

As a result, an annular space 42 in which magnetic particles 44 are accommodated.
Therefore, it is possible to reliably avoid the above-mentioned deterioration in torque transmission performance, poor clutch disengagement, etc. caused by oil intrusion.

It should be noted that the foreign substances generated near the hub portion 58 are not limited to oil, but also include the hub portion 58 and the output shaft 12.
There is also friction powder that accompanies sliding with the clutch, and even if such friction powder moves outward due to centrifugal force, it is prevented from entering the central part of the clutch in the same way as the oil mentioned above. Further, in the case of friction powder, it may be scattered from the end of the hub portion 58 on the opposite side from the first and second annular walls 74 and 76, but such friction powder is prevented by the shielding member 86. outward movement is impeded,
It will be discharged to the outside of the clutch along the tapered inner surface.

Note that a discharge hole 8 that communicates the annular groove 80 with the outside
2 may be simply made by making a hole in the first annular wall 74, but as shown in an enlarged view in FIG. Preferably, a protrusion 88 is provided and a discharge hole 82 is formed in the distal wall thereof. I mean,
When the discharge hole 82 is formed at the tip of the protrusion 88, as shown in FIG. This is because intrusion into the annular groove 80 can be prevented, and foreign matter received in the annular groove 80 can be easily collected into the discharge hole 82.

Further, the plate member constituting the annular protrusion 46 shown in FIG. It may be fixed to the section. In addition, the front labyrinth member 2
The first annular wall 74 may be formed by forming a second annular wall 76 continuously on the inner circumference of the second annular wall 76 as shown in FIG. can.

On the other hand, as shown in FIG. 6, in addition to the first and second annular walls 74 and 76, it is also possible to form a third annular wall 90 on the inner circumference of the front labyrinth member 26. This third annular wall 90
is located at a predetermined gap from the annular wall 76 of the hub portion 58 to the other end side of the hub portion 58, and has a second
A second annular groove 92 parallel to the annular groove 80 is formed between the second annular wall 76 and the annular groove 80 . A second annular wall 76 located on the bottom side
is provided with a discharge hole 94 that allows both annular grooves 92 and 80 to communicate with each other. By adding the third annular wall 90 in this way, even if there is oil that cannot be received by the annular groove 80, it will be received by the annular groove 92 and discharged to the outside through the discharge holes 94 and 82. Therefore, foreign matter can be more reliably prevented from entering the central part of the clutch.

Furthermore, the bag-shaped structure such as the annular groove 80 as described above can be adopted not only on the front labyrinth member 26 side, but also on the rear labyrinth with an annular groove constituted by an annular wall similar to that described above. It is also possible to provide it on the side of the member so as to discharge oil and the like to the outside.

In addition, it goes without saying that the present invention may be implemented with various modifications and improvements based on the knowledge of those skilled in the art, as long as they do not depart from the spirit of the present invention.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a magnetic particle type electromagnetic clutch applied to an automobile as an embodiment of the present invention.
The figure is a partially sectional view showing an enlarged view of the main part thereof. 3 is a partially enlarged cross-sectional view showing section A in FIG. 2, and FIG. 4 is a view taken in the direction of arrows in FIG. 3. FIG. 5 is a partial sectional view showing the main part of another embodiment of the present invention, and FIG. 6 is a partial sectional view showing the main part of still another embodiment of the invention. 12: Output shaft (driven shaft), 20: Yoke (driving member), 24: Inner peripheral friction surface (inner peripheral surface), 34: Rotor, 38: Outer peripheral friction surface (outer peripheral surface), 40: Gap, 42: annular space, 44: magnetic powder, 58: hub section, 74: first annular wall, 76: second annular wall,
80: Annular groove, 82: Discharge hole.

Claims (1)

[Claims for Utility Model Registration] A cylindrical driving member that is rotated around a center line, a cylindrical hub portion for connecting to a driven shaft in the center, and a cylindrical hub portion that is located inside the driving member and is concentric therewith. a driven member that is relatively rotatable; and an annular space that is attached to both ends of the driving member and that accommodates magnetic particles together with an inner circumferential surface of the driving member and an outer circumferential surface of the driven member. an annular labyrinth member to form an annular labyrinth member, and by magnetically coupling the magnetic particles in a gap between the inner peripheral surface of the driving member and the outer peripheral surface of the driven member, the rotational force of the driving member is reduced. In the magnetic particle type electromagnetic clutch of the type that transmits the transmission to the driven member, a first annular wall having an inner peripheral edge close to an outer peripheral surface of one end of the hub part is provided on one inner peripheral part of the labyrinth member; The first annular wall is located at a predetermined gap toward the other end of the hub portion in the center line direction, and is brought into close contact with the outer peripheral edge of the first annular wall at the outer peripheral edge. A magnetic particle type electromagnetic device, characterized in that a second annular wall is provided between the wall and the second annular wall to form an inward annular groove, and a discharge hole communicating with the annular groove is formed in the first annular wall. Clutch.