JP2004076828A - Clutch device - Google Patents

Abstract

An object of the present invention is to reduce the manufacturing cost of a clutch hub.
A plurality of drive plates (40, 42) and a driven plate (45) are alternately arranged between an inner peripheral surface of a clutch drum (31) and an outer peripheral surface of a clutch hub (33). Each of the drive plates 40 and 42 is spline-fitted to the clutch hub 33, while each driven plate 45 is spline-fitted to the clutch drum 31. The axial end of the spline portion 35 of the clutch hub 33 has at least one first end surface 36 and a second end surface 37 adjacent to the first end surface 36. The first and second end faces 36 and 37 have an arc shape extending in the circumferential direction of the clutch hub 33, and the second end face 37 protrudes more in the axial direction than the first end face 36. .
[Selection diagram] FIG.

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a clutch device, and more particularly, to a lubrication structure for a multi-plate clutch.
[0002]
[Prior art]
For example, a transfer clutch incorporated in an automatic transmission (AT) for a four-wheel drive vehicle (4WD) includes a clutch drum, a clutch hub, and a group of plates (a drive plate and a driven plate) alternately arranged therebetween. Plate). The facing surface of the plate and the part where the spline is fitted need to be supplied with oil and lubricated in order to cope with heat generation and wear.
[0003]
FIG. 9 is a cross-sectional view of a conventional clutch hub, and shows a cross-sectional shape of an upper half with respect to an axis indicated by a chain line. The clutch hub 50 has a spline portion 50a in which splines extending in the axial direction are formed on the outer peripheral surface. At both ends of the spline portion 50a, ribs 51 protruding toward the inner peripheral surface side (downward in the figure) are integrally formed in an annular shape. The rib 51 has a function as a damming portion for restricting the oil in the oil sump 52 from flowing out from the end. When the clutch hub 50 rotates, the oil supplied from the rotating shaft of the clutch hub 50 accumulates in the oil sump 52 by centrifugal force. The accumulated oil is discharged from an oil discharge hole 53 penetrating in the radial direction of the spline portion 50a, whereby the members disposed on the outer peripheral surface side of the spline portion 50a, that is, the drive plate and the driven plate are lubricated. Is done.
[0004]
[Problems to be solved by the invention]
However, the manufacturing process of the clutch hub 50 having the above-described structure is complicated, so that there is a limit in reducing the manufacturing cost. For example, when the clutch hub 50 is molded by sintering, it is necessary to remove the frame of the clutch hub 50. In the sinter molding process, the rib 51 cannot be formed, and a draft corresponding to the oil sump 52 is formed in a portion corresponding to the oil sump 52 (a tapered shape that increases in diameter toward the end portion) in order to allow the frame to be removed. Need to be provided. Then, after the clutch hub 50 is taken out, the ribs 51 and the oil sump 52 are formed by cutting with a lathe, and the oil discharge holes 53 are formed by drilling with a drill. As described above, the conventional clutch hub 50 needs to be machined after sintering, and thus has a disadvantage of increasing the manufacturing cost.
[0005]
The present invention has been made in view of such circumstances, and an object of the present invention is to reduce the manufacturing cost of a clutch hub.
[0006]
[Means for Solving the Problems]
In order to solve the problem, a clutch device according to the present invention includes a clutch drum having a spline formed on an inner peripheral surface, and a spline portion disposed in the clutch drum and having a spline formed on an outer peripheral surface. And a plurality of drive plates, which are disposed between the inner peripheral surface of the clutch drum and the outer peripheral surface of the clutch hub, and are spline-fitted to the clutch hub, and the inner peripheral surface of the clutch drum and the outer peripheral surface of the clutch hub. A plurality of driven plates are interposed between the drive plates and alternately arranged with the drive plates, and are spline-fitted to the clutch drum. The end of the spline portion has at least one first end surface having an arc shape extending in the circumferential direction of the clutch hub, and at least one second end surface. The second end face projects in the axial direction from the first end face.
[0007]
Here, in the present invention, it is preferable to provide an oil groove communicating between the inside and the outside in the radial direction of the clutch hub on the first end face.
[0008]
In the present invention, the drive plate located between the first end face and the second end face in the axial direction has an inner diameter smaller than the inner diameter of the spline portion of the clutch hub, and includes the second end face. It has an opening that engages with the protruding portion.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a sectional view of an automatic transmission (AT) for a four-wheel drive vehicle (4WD) to which the clutch device according to the present embodiment is applied. Power from an engine (not shown) is transmitted to an input shaft 3 of the automatic transmission 1 via a torque converter 2. The power transmitted to the input shaft 3 is shifted by a transmission mechanism including two planetary gears A and B, a high clutch 6, a reverse clutch 7, a 2 & 4 brake 8, a low clutch 9, a low & reverse brake 10, and the like, and then output. It is transmitted to the shaft 4. These clutches and brakes 6 to 10 are engaged / disengaged by hydraulic control by the control valve 11, and the shift speed is set accordingly. The post-shift power transmitted to the output shaft 4 is input to the center differential and distributed, and one power is transmitted to the drive pinion shaft 5 via the carrier 16, the reduction drive gear 12, and the reduction driven gear 13. Then, it is transmitted to the front wheels via the differential device 14. The other power is transmitted to the rear drive shaft 15 that drives the rear wheels via the second sun gear 20. An operation limiting clutch 30 is provided between the carrier 16 and the rear drive shaft 15, which are transmission members of the distributed power.
[0010]
FIG. 2 is a cross-sectional view of the clutch device according to the present embodiment, and shows a 4WD center differential 60 and a differential limiting clutch 30 (hereinafter, referred to as a transfer clutch 30) provided therein. The center differential 60 has a first sun gear 17 formed on the output shaft 4 of the transmission 1, a second sun gear 20 formed on the rear drive shaft 15, and an integrally formed first gear meshing with these sun gears 17 and 20. , A second pinion 19, and a carrier 16 that supports these pinions 18, 19 in a compound planetary gear system. A transfer clutch 30 is provided between the carrier 16 as an output member on the front wheel side and the rear drive shaft 15 as an output member on the rear wheel side. In the center differential 60 thus configured, power is distributed to the front wheel side and the rear wheel side at a basic distribution ratio by setting the gear specifications of the planetary gear. Then, according to the traveling state or the road surface state, for example, when the rear wheel slips, the transfer clutch 30 is engaged to control the differential rotation of the center differential 60. By transmitting the power transmitted to the rear wheels to the front wheels by the transfer clutch 30, the driving force is secured as a 4WD vehicle, and the traveling performance can be improved.
[0011]
The automatic transmission 1 is provided with a lubricating oil passage 22 that communicates between the output shaft 4 and the rear drive shaft 15 which are arranged on the same axis as the input shaft 3. The oil discharged from the oil pump 21 is supplied. The shafts 3, 4, and 15 are provided with a plurality of radially extending oil holes 24 to 29 that communicate with the lubricating oil passage 22. The oil discharged from these oil holes 24 to 29 lubricates the above-described transmission mechanism, transfer clutch 30 and the like.
[0012]
The transfer clutch 30 mainly includes a clutch drum 31, a clutch hub 33, a plurality of drive plates 40 and 42, and a plurality of driven plates 45. The clutch drum 31 has a spline portion 32 in which a spline is formed on the inner peripheral surface. A clutch hub 33 that is spline-fitted to the rear drive shaft 15 is disposed inside the clutch drum 31.
[0013]
3 is a front view of the clutch hub 33, FIG. 4 is a plan view, and FIG. 5 is a cross-sectional view taken along line AA of FIG. The clutch hub 33 can be formed only by sintering without performing machining such as cutting and drilling. As shown in FIG. 5, the clutch hub 33 has a substantially E-shaped cross section, an inner peripheral portion 33a having an inner spline on the inner periphery, a spline portion 35, and a flange connecting these portions 33a, 35. It has a portion 33c. The inner peripheral portion 33a is spline-fitted to the rear drive shaft 15, and a plurality of first oil grooves 34 are provided on the end face thereof in the radial direction.
[0014]
The spline portion 35 corresponds to the outer peripheral portion of the clutch hub 33, and a spline is provided on the outer peripheral surface. As shown in FIG. 3, four first end faces 36 and four second end faces 37 are alternately arranged along the circumferential direction at the ends (both ends in the present embodiment) of the spline portion 35. Is provided. The second end face 37 protrudes in the axial direction from the first end face 36. In other words, the end of the spline portion 35 has a cutout portion (concave portion) corresponding to the first end surface 36 and a projecting portion (convex portion) corresponding to the second end surface 37 in the circumferential direction. Are alternately adjacent to each other. A second oil groove 39 is provided on each of the first end surfaces 36 that are concavely concave, and the second oil groove 39 communicates between the inside and the outside of the clutch hub 33 in the radial direction. I do. The number of the first and second end faces 36 and 37 is sufficient if at least one of each is present, but it is preferable to provide a plurality of them.
[0015]
FIG. 6 is an enlarged sectional view showing a main part of the transfer clutch 30. FIG. 7 is an exploded view of the drive plates 40 and 42 and the driven plate 45. FIG. 8 is a diagram showing an engagement state between the clutch hub 33 and the drive plate 42. As shown in FIGS. 6 and 7, between the inner peripheral surface of the clutch drum 31 and the outer peripheral surface of the clutch hub 33, a plurality of drive plates 40 and 42 and a plurality of driven plates 45 are alternately arranged in the axial direction. Are located in Of these, facing materials are adhered to the side surfaces of the drive plates 40 and 42 in order to secure a frictional force at the time of fastening.
[0016]
Here, each of the first drive plates 40 disposed in the middle is disposed between a pair of adjacent driven plates 45. An inner spline is formed on the inner peripheral portion of each first drive plate 40 so as to be splined with the spline portion 35 of the clutch hub 33.
[0017]
On the other hand, the second drive plate 42 located on the end side, that is, between the first end face 36 and the second end face 37 is also arranged between a pair of adjacent driven plates 45. The second drive plate 42 has an inner diameter smaller than the inner diameter of the spline portion 35 of the clutch hub 33, and has a plurality of openings 43 provided in the circumferential direction. In these openings 43, splines that can be fitted with the spline portions 35 of the clutch hub 33 are formed. The opening 43 is provided so as to correspond to the second end surface 37 of the spline portion 35 of the clutch hub 33, and engages with a projecting portion (convex portion) including the second end surface 37 of the clutch hub 33. Combine.
[0018]
Further, an outer spline is formed on the outer peripheral portion of each driven plate 45, and the outer spline is spline-fitted with the spline portion 32 of the clutch drum 31.
[0019]
The reason why the inner diameters of the second drive plates 42 located at both ends are smaller than the inner diameter of the spline portion 35 is that the plate 42 has a function of blocking oil. As shown in the assembled state of FIG. 6, the second drive plate 42 protrudes in a rib shape on the inner peripheral surface side of the spline portion 35. Thus, an oil reservoir 47 is formed on the inner peripheral surface of the spline portion 35 by the projecting portion of the second drive plate 42 and the flange portion 33c. When the rear drive shaft 15 rotates, the oil discharged from the oil hole 29 is stored in the oil sump 47. That is, most of the oil discharged from the oil hole 29 of the rear drive shaft 15 flows along the flange portion 33 c of the clutch hub 33 due to the centrifugal force caused by the rotation of the clutch hub 33, and accumulates in the oil sump 47.
[0020]
As described above, the second end face 37 projects in the axial direction from the first end face 36. For this reason, when the second drive plate 42 is spline-fitted to the spline portion 35 of the clutch hub 33, the projecting portion including the second end face 37 engages with the opening 43 of the second drive plate 42. Further, between the first end surface 36 corresponding to the cutout portion and the side surface of the second drive plate 42, a slight gap is set in a clutch engaged state. Therefore, an oil discharge port communicating between the inside and the outside of the spline portion 35 is formed by the gap between the first end surface 36 and the second drive plate 42 and the second oil groove 39. As a result, the oil stored in the oil sump 47 flows through the oil discharge port and is discharged toward the outer peripheral surface side of the clutch hub 33.
[0021]
As described above, in the present embodiment, the oil reservoir 47 can be formed only by assembling the drive plates 40 and 42 and the driven plate 45 between the clutch drum 31 and the clutch hub 33 by spline fitting. Become. Therefore, there is no need to perform machining such as cutting and drilling on the clutch hub 33. As a result, the manufacturing cost of the clutch hub 33 can be reduced, and the oil sump 47 can be easily formed.
[0022]
In the above-described embodiment, the clutch hub 33 having a substantially D-shaped cross section has been described as an example. However, the present invention is not limited to this, and may be, for example, a drum shape. . Further, in the present embodiment, the transfer clutch 30 has been described as an example of the clutch device, but the present invention can be applied to other multi-plate clutches.
[0023]
In the above-described embodiment, the second drive plate 42 having a different shape from the first drive plate 40 is used as the drive plate located between the first end surface 36 and the second end surface 37 in the axial direction. Used. However, a plate having the same shape as the first drive plate 40 may be used as the end plate. In this case, the drive plate at the end has no damming function. However, the oil that has flowed into the oil sump 47 is supplied to the outer peripheral surface side of the spline portion 35 via the first end surface 36 that communicates with the inside and outside in the radial direction, so that the plates can be lubricated. In this case, since the entire first end face 36 functions as an oil passage, it is not always necessary to form the above-described second oil groove 39 on the first end face 36.
[0024]
【The invention's effect】
As described above, according to the present invention, a lubricating structure for a multi-plate clutch can be realized only by assembling the drive plate and the driven plate by spline fitting between the clutch drum and the clutch hub. Further, it is not always necessary to perform machining such as cutting with a lathe or drilling with a drill as in the related art. As a result, the manufacturing cost of the clutch hub can be reduced.
[Brief description of the drawings]
FIG. 1 is a sectional view of an automatic transmission to which a clutch device according to the present embodiment is applied. FIG. 2 is a sectional view of a transfer clutch. FIG. 3 is a front view of a clutch hub. FIG. 4 is a plan view of a clutch hub. FIG. 6 is a sectional view taken along line AA in FIG. 3. FIG. 6 is an enlarged sectional view showing a main part of the transfer clutch. FIG. 7 is an exploded view of a drive plate and a driven plate. FIG. 8 is an engagement between a clutch hub and a drive plate. FIG. 9 shows a state. FIG. 9 is a sectional view of a conventional clutch hub.
30 differential limiting clutch (transfer clutch)
31 clutch drum 32 spline portion 33 clutch hub 33a inner peripheral portion 33c flange portion 34 first oil groove 35 spline portion 36 first end face 37 second end face 39 second oil groove 40 first drive plate 42 second Drive plate 43 opening 45 driven plate 47 oil sump

Claims (3)

In the clutch device,
A clutch drum with splines formed on the inner peripheral surface,
A clutch hub having a spline portion disposed in the clutch drum and having a spline formed on an outer peripheral surface;
A plurality of drive plates arranged between the inner peripheral surface of the clutch drum and the outer peripheral surface of the clutch hub, and spline-fitted to the clutch hub;
A plurality of driven plates are disposed between the inner peripheral surface of the clutch drum and the outer peripheral surface of the clutch hub, are alternately arranged with the drive plates, and are spline-fitted to the clutch drum. And
The end of the spline portion is
At least one first end face having an arc shape extending in a circumferential direction of the clutch hub;
A clutch device having an arc shape extending in a circumferential direction of the clutch hub, and having at least one second end surface protruding in an axial direction from the first end surface. 2. The clutch device according to claim 1, wherein the first end face is provided with an oil groove communicating between a radially inner side and an outer side of the clutch hub. 3. The drive plate located between the first end face and the second end face in the axial direction has an inner diameter smaller than the inner diameter of the spline portion and engages with a projecting portion including the second end face. The clutch device according to claim 1, wherein the clutch device has an opening that is formed.

Images