JPH01250626A - Multiple disk clutch using electroviscous fluid - Google Patents

Abstract

PURPOSE:To maintain good torque transfer performance by holding each spacer made of an insulating material among multiple input clutche disks, and forming each of projections, being opposed to output clutche disks at regular intervals in the axial direction, solidly with the spacer as one body, in a clutch which utilizes an electroviscous fluid as a torque transfer medium. CONSTITUTION:In a clutch which utilizes an electroviscous fluid L as a torque transfer medium, each space made of an insulating material is held among multiple input clutch disks 7, and each axial position and mutual intervals of the input clutch disks 7 are fixed. In addition, each projection 12a, being opposed to each output clutch disk 16 at regular intervals in the axial direction, is solidly formed with the spacer 12 as one body. With this formation, an interval C1 between these input and output clutch disks 7, 16 can be set as small as possible owing to these spacers 12 and projections 12a, and that both clutch disks 7, 16 are made keepable so as not to come into contact with each other. Therefore augmentation of transfer torque by means of multiplication of the clutches is achievable, thus good torque transfer performance is maintainable.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to electro-rheological fluids whose viscosity increases significantly due to an external electric field.
lds) as a torque transmission medium.

(Prior art and its problems) An electrorheological fluid is a fluid in which solid particles (dispersoids) are dispersed in an insulating oily liquid (dispersion medium), and its viscosity increases significantly due to the Winslow effect caused by an external electric field. It is a suspension.

Generally speaking, in a wet hydraulic piston clutch where the clutch plate is immersed in a reservoir, torque is transmitted by directly pressing the input clutch plate and the output clutch plate, but in the clutch using the electrorheological fluid mentioned above, the input clutch plate is always connected to the output clutch plate. It is necessary to maintain a constant axial spacing between the output clutch plate and the insulating state. In order to promote an increase in the viscosity of the electrorheological fluid, it is preferable to make the above distance as narrow as possible, but it becomes difficult to avoid contact between the input clutch plate and the output clutch plate.

Because of these conditions, conventional clutches that utilize electrorheological fluids have only been developed as single-plate clutches or cylinder-type clutches.

However, the power transmission force of the electrorheological fluid itself is relatively weak, so single-plate clutches lack the transmission torque capacity, making it difficult to use them in high-torque clutches such as those used in automobiles, and multi-plate clutches have become essential. ing.

(Object of the Invention) An object of the present invention is to reliably maintain the gap between the man and output clutch plates at a predetermined interval so that an electrorheological fluid can be satisfactorily applied to a multi-disc clutch. The purpose is to prevent contact between clutch plates.

(Technical Means for Achieving the Object) In order to achieve the above object, the present invention spline-fits a plurality of annular input clutch plates to the input side rotating member at intervals in the axial direction, and A plurality of annular output clutch plates disposed between each of the input clutch plates are spline-fitted, and a spacer made of an insulating material is interposed between adjacent input clutch plates to maintain a constant axial distance between them. The spacer has an alignment protrusion that faces the side surface of the output side clutch plate at a narrower interval than the input side clutch plate. By filling one of the input and output sides with a positive electrode and connecting the other with a negative electrode, torque is transmitted from the input clutch plate to the output clutch plate via the electrorheological fluid.

(Function) By applying a high voltage, for example, 3 to 5 KV, between the input clutch plate and the output clutch plate, a strong electric field is generated and the viscosity of the electrorheological fluid increases rapidly. Rotational torque is transmitted from the input clutch plate to the output clutch plate. At this time, the input clutch plates are always kept at a constant distance by spacers made of insulating material, and the output clutch plates are aligned by the convex parts on both sides.
That is, the axial position is regulated. Therefore, a stable electric field strength is maintained, the viscosity of the electrorheological fluid is stabilized, and torque transmission performance is stabilized. It also reliably prevents contact between people and the output clutch plate, and maintains an insulated state.

In the stage before high voltage is applied, that is, in the latch OFF state, the electrorheological fluid is in a state of low viscosity, so no rotational torque is transmitted. At this time, the temporary input clutch is rotating with respect to the output clutch plate which is stopped, but the alignment, that is, the axial position of the output clutch plate is regulated by the convex portions on both sides of the output clutch plate.

(Example) Fig. 1 shows an example of a multi-disc clutch to which the present invention is applied. In Fig. 1, the input shaft 1 and the output shaft 2 are arranged on the same axis, and the clutch case etc. bearing 20
．． It is supported via 21 etc. An input hub 3 is spline-fitted to the outer peripheral spline teeth 1a of the input shaft 1, and is locked by a locking ring 8 or the like so that it cannot move in the axial direction. A large number of metal annular input clutch plates 7 are arranged on the outer periphery of the hub 3.
is arranged, and the input clutch plate 7 has its inner peripheral protrusion 7a engaged with the outer peripheral spline teeth 6 of the hub 3, and rotates together with the hub 3.

A boss portion 19 of an output-side cylinder 4 is spline-fitted to the output shaft 2, so that the cylinder 4 rotates together with the output shaft 2. A large number of metal annular output clutch plates 16 are arranged inside the cylinder 4 in the radial direction.
, thereby rotating together with the cylindrical body 4.

Each output clutch plate 16 is movable in the axial direction, and is arranged between adjacent input clutch plates 7 and at both ends in the axial direction.

According to the present invention, a pair of annular spacers 12 made of an insulating material are arranged between the input clutch plates 7, and the surfaces 12 are made of a heat-resistant resin such as polyacetal. Each spacer 12 is held between input clutch plates 7, and the input clutch plates 7 and spacers 12 are fixed so as not to be able to move in the axial direction by presser plates 9 and locking rings 10 at both axial ends. Incidentally, spacers 12 made of an insulating material are also arranged between the input clutch plate 7 and the presser foot 9 at both ends in the axial direction.

Each spacer 12 has a plurality of outward protrusions 12a extending radially outward and integrally formed at intervals in the circumferential direction, and each protrusion 12 has its axial side surface facing the input clutch plate 7. The other side faces the output clutch plate 16 with an interval C2 of about 0.1 m+s to 0°3n++e. Further, the input clutch plate 7 and the output clutch plate 16 are opposed to each other with an interval C1 of about 1 mm, for example.

The input clutch plate 7 is connected to the positive electrode of the high voltage power supply 23 via the hub 3, input shaft 1, bearing 20 and changeover switch 24.
It is possible to apply a voltage of KV. −
The force output clutch plate 16 is connected to a ground wire (negative electrode) via the cylindrical body 4 and the bearing 21.

The electrorheological fluid is filled in the space between the person and the output clutch plate 7.16, and is held by a clutch case or the like (not shown) to prevent leakage to the outside of the clutch. As explained in the prior art section, electrorheological fluids are made by dispersing solid particles (dispersoids) in an insulating oily liquid (dispersion medium), and the Winslow effect occurs due to an external electric field, causing a significant increase in viscosity. It is a growing suspension.

FIG. 2 is a view of the spacer 12 in the direction of the arrow ■ in FIG. 1, and the convex portions 12a are arranged at equal intervals in the circumferential direction.

Figure 3 shows the person, output clutch plate 7.16 and spacer 12.
1, the surface of the convex portion 12a facing the output clutch plate 16 is formed in an arc shape. That is, it is formed so as to approach the output clutch plate 16 toward the center in the circumferential direction, and the distance between the top of the convex portion 12a and the output clutch plate 16 is the above-mentioned distance C2.

4 shows the state of spline fitting between the input hub 3 and the input clutch plate 7, and FIG. 5 shows the state of spline fitting between the output side cylinder 4 and the output clutch plate 16. .

Explain the operation. When the changeover switch 24 in FIG. 1 is turned OFF, no electric field is generated between the person and the output clutch plate 7.16, so the viscosity of the electrorheological fluid is small and no rotational torque is transmitted.

When the changeover switch 24 is turned on, the input clutch plate 7 is charged to 3 to 5 KV, and a strong electric field is generated between both clutch plates 7.16. As a result, the viscosity of the electrorheological fluid increases rapidly, and rotational torque is transmitted from the input clutch plate 7 to the output clutch plate 16 via this fluid.

During rotation, the axial position and mutual spacing of the input clutch plates 7 are precisely fixed by the spacers 12. - The force output clutch plate 16 is limited in its axial movement by the convex portion 12a of the spacer 12, so that it will not come into contact with the input clutch plate 7 and will not be short-circuited. Further, if the side surface of the convex portion 12a is formed into an arc shape as shown in FIG.
6, a so-called wedge action occurs, and the convex portion 1
2a increases pressure near the center of the output clutch plate 16.
An axial force is applied in a direction to separate the convex portion 12a from the convex portion 12a. This force is applied to the protrusions 12 on both sides in the axial direction with respect to the output clutch plate 16.
Since it engages from the a portion, the output clutch plate 16 does not come into contact with the convex portions 12a on both sides. Moreover, it also serves as fluid lubrication between the convex portion 12a and the output clutch plate 16. Therefore, seizure of the convex portion 12a etc. can also be prevented.

Furthermore, as described above, due to the wedge action due to the arc shape of the convex portion 12a, the axial position of the output clutch plate 16 is stabilized, and the interval C2 is stabilized, so the electric field strength is also stabilized, and the rotational torque transmission efficiency is also improved. Stabilize.

(Another embodiment) (1) In Fig. 1, the cylinder 4 is applied to the output side and the inner hub 3 is applied to the input side clutch, but the cylinder 4 is applied to the input side and the hub 3 is applied to the output side. It can also be applied to clutches.

(2) In FIG. 3, the side surface of the convex portion 12a is made into an arc shape so that a wedge action will occur no matter which direction the input clutch plate 7 rotates with respect to the output clutch plate 16. When the clutch plate 7 always rotates in only one direction, only one side of the front side in the direction of rotation may be formed into an inclined shape or an arc shape.

In the case of low-speed rotation, it is possible to achieve the axial alignment function even by chamfering or rounding the circumferential corners of the convex portions.

(Effects of the Invention) As described above, the present invention provides a clutch that utilizes electrorheological fluid as a torque transmission medium, in which a spacer 12 made of an insulating material is sandwiched between a large number of input clutch plates 7. The axial position and mutual spacing of the varnish spacer 12 and the convex portion 12a are fixed, and the convex portion 12a facing the output clutch plate 16 at a constant distance in the axial direction is formed integrally with the spacer 12. This makes it possible to keep the interval C1 between the output clutch plates 7.16 as small as possible and to prevent the two clutch plates 7.16 from coming into contact with each other, thereby increasing the transmitted torque by increasing the number of clutch plates. Maintains good torque transmission performance.

In other words, in the case of multi-disc clutches, the number of people, output clutch plates 7.
Since the interval CI of 16 is maintained as small as possible and without fluctuation, the electric field strength can be maintained as high and stable as possible, and the transmission efficiency of rotational torque is improved and stabilized.

In addition, since the output clutch plates 7.16 are never in contact with each other, for example, the viscosity of the electrorheological fluid is prevented from being inadvertently reduced due to a short circuit between the two clutch plates 7.16, and clutch slippage is prevented. I can do that.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a multi-disc clutch using electrorheological fluid to which the present invention is applied, Fig. 2 is a view of the spacer in Fig. 1,
Figure 3 is a view of both clutch plates and spacers in the direction of the arrow in the first drawing;
Figures 4 and 5 are TV-IV and v-■ of Figure 1, respectively.
FIG. 1...Input shaft, 2...Output shaft, 7.
...Input clutch plate, 12...Spacer, 12a...
・Convex portion, 16...Output clutch plate, L...Electrorheological fluid patent applicant Daikin Seisakusho Co., Ltd.

Claims (1)

[Claims] A plurality of annular input clutch plates are spline-fitted to the input-side rotating member at intervals in the axial direction, and a plurality of annular output clutch plates arranged between the input clutch plates are spline-fitted to the output-side rotating member. A spacer made of an insulating material is interposed between adjacent input clutch plates to maintain a constant axial distance between them, and the spacer has a spacer that is narrower than that of the input clutch plate from the side surface of the output side clutch plate. Opposed alignment convex parts are formed, and an electrorheological fluid whose viscosity increases rapidly due to an external electric field is filled between both clutch plates, and one of the input and output sides is connected to the positive electrode and the other to the negative electrode. This is a multi-plate clutch that uses electrorheological fluid to transmit torque from the input clutch plate to the output clutch plate via electrorheological fluid.