JP3710629B2 - Coupling structure of clutch drum and parking gear - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a coupling structure of a clutch drum and a parking gear in an automatic transmission for a vehicle.
[0002]
[Prior art]
In an automatic transmission using a torque converter, especially for a vehicle, in order to reliably prevent movement due to external force at the time of parking, a rotating shaft connected to the wheel drive shaft without sliding, generally the rear side excluding the input shaft A parking gear is provided on the rotation shaft of the motor, and the rotation can be locked by meshing with the parking gear.
When the parking gear is provided on the intermediate shaft, for example, it may be adjacent to a clutch mechanism as a part of the speed change mechanism. An example of this is disclosed in Japanese Utility Model Publication No. 58-114946 and shown in FIG.
[0003]
In this example, an output gear 61 to the next stage is formed at one end of the intermediate shaft 60, and a parking gear 64 is welded to the shoulder portion thereof. Further, a clutch mechanism 70 including a clutch drum 71, friction plates 75 and 76, a piston 77 and the like is disposed adjacent to the parking gear 64.
The parking gear 64 has a cylindrical portion 66 on the outer periphery of the disc portion 65. On the outer peripheral surface of the cylindrical portion 66, teeth 67 having a width shorter than the length of the cylindrical portion are formed close to the output gear 61 side.
[0004]
One end of the clutch drum 71 is fitted on the outer peripheral surface of the cylindrical portion 66 so as to contact the side surface of the tooth 67, and is welded between the end surface of the cylindrical portion 66 of the parking gear 64 and the inner peripheral surface of the clutch drum 71.
A spline 72 is formed on the clutch drum 71, and a friction plate 75 is engaged with the spline 72. The friction plates 76 and the friction plates 75 that engage with the other rotating member 80 are alternately arranged.
[0005]
On the other hand, the parking gear 64 forms a cylinder portion 68 that accommodates the piston 77, and the piston 77 can slide in the axial direction along the inner peripheral surface of the cylindrical portion 66. Is pressed.
According to the above configuration, by coupling the parking gear 64 and the clutch drum 71, the clutch mechanism can be arranged compactly without taking up space.
[0006]
[Problems to be solved by the invention]
However, in the conventional coupling structure of the clutch drum and the parking gear, the welding (W3) portion between the parking gear 64 and the clutch drum 71 is in the vicinity of the edge of the cylinder portion 68 formed in the parking gear. There is a problem that the accuracy of the piston seal portion is deteriorated.
[0007]
Further, since the cylinder portion is formed by the parking gear 64, the cylindrical portion 66 requires a predetermined dimension and becomes thick in the axial direction, resulting in high manufacturing costs.
Furthermore, since the clutch drum 71 is coupled following the teeth 67 of the parking gear, the impact load applied to the parking gear is also applied to the clutch drum. Therefore, it is necessary to increase the plate thickness of the clutch drum 71.
[0008]
Therefore, in view of the above-described conventional problems, the present invention provides a clutch drum / parking gear coupling structure in which the cylinder portion on which the piston slides is not distorted and the manufacturing cost of the parking gear and clutch drum can be reduced. The purpose is to provide.
[0009]
[Means for Solving the Problems]
Therefore, according to the present invention, a clutch mechanism that presses a friction plate engaged with a clutch drum with a piston and a parking gear are provided adjacent to each other in the axial direction on the rotation shaft of the automatic transmission. A spline portion that engages with the plate, an outer peripheral wall portion that forms a cylinder that accommodates the piston and whose inner peripheral surface is a sliding surface of the piston, and a vertical wall portion that extends radially inward from the outer peripheral wall portion The parking gear is provided with teeth on the outer periphery of the disk portion extending in the radial direction, and the inner peripheral edge of the vertical wall portion of the clutch drum is welded to the disk portion of the parking gear.
[0010]
As a result, a cylinder on which the piston slides is formed on the clutch drum, and the clutch drum is welded to the disk portion of the parking gear at the inner peripheral edge of the vertical wall portion away from the piston sliding surface. No distortion occurs.
[0011]
Similarly, since the clutch drum is welded to the disk portion of the parking gear at the inner peripheral edge of the vertical wall portion, the impact load applied to the parking gear is borne by the tooth portion of the parking gear and the output shaft, and directly reaches the clutch drum. There is no need to increase the thickness of the clutch drum.
Furthermore, since it is not necessary to form the cylinder portion in the parking gear, the parking gear can be thin in the axial direction, and can be manufactured from a plate material by press molding, for example.
[0012]
Also, an output gear is formed on the rotary shaft, a shoulder portion having a diameter smaller than the root diameter of the output gear is formed on the clutch mechanism side, and the parking gear has an annular shape and its inner peripheral edge is fitted into the shoulder portion. It can be welded to the rotating shaft at the fitting portion.
Since the parking gear is welded to the rotating shaft at a relatively large radius, the coupling strength is high, and high rigidity is ensured even if the disk portion of the parking gear is thin.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described by way of examples.
FIG. 1 is a sectional view around a parking gear showing the configuration of the embodiment, and FIG. 2 is an enlarged view of a main part thereof.
A first shaft 15 including an output gear 16 is supported via a bearing 30 in a transmission case 19 of the automatic transmission. The outer end 17 of the first shaft 15 protrudes and is inserted into the support hole 12 of the transmission case, and a support hole 18 is provided at the center of the inner end to support the coaxial second shaft 25 via the bearing 31. are doing.
[0014]
A shoulder 19 having a diameter slightly smaller than the root diameter is formed on the output gear 16 formed on the inner side of the bearing position 30. A cylindrical portion 20 extending in the axial direction having a smaller diameter is formed at the end of the shoulder portion 19.
A parking gear 33 is fitted in the shoulder 19. The parking gear 33 has an annular shape obtained by press-molding a plate material. The parking gear 33 is provided with teeth 35 on the outer periphery of the disk portion 34 extending in the radial direction. The inner peripheral edge of the disk portion 34 is fitted into the shoulder portion 19 and welded at the fitting portion (W1). Has been.
[0015]
A clutch mechanism 40 is provided on the inner side of the parking gear 33. The clutch mechanism 40 includes a clutch drum 41, friction plates 45 and 46, a piston 47, and the like.
The clutch drum 41 includes a spline portion 42 having a diameter larger than that of the parking gear 33, an outer peripheral wall portion 43 having substantially the same diameter as the parking gear 33, and a vertical wall portion 44 extending radially inward from the outer peripheral wall portion 43. The inner peripheral edge of the vertical wall 44 of the clutch drum is offset toward the parking gear 33 and is positioned in a recess 36 formed in the disk 34 of the parking gear, and the inner peripheral edge is welded to the disk 34 (W2). Has been.
[0016]
A rotating member 50 having a spline 51 facing the spline portion 42 is disposed inside the clutch drum 41, and a plurality of friction plates 45 and 46 that respectively engage with the spline portion 42 and the spline 51 are provided alternately in the axial direction. It is done.
A ring-shaped cylinder 48 is formed in the outer peripheral wall portion 43 of the clutch drum 41, and the outer peripheral surface 49 of the outer peripheral wall portion 43 and the outer peripheral surface 21 of the cylindrical portion 20 of the first shaft 15 are in contact with the sliding surface of the piston 47. It has become.
[0017]
The piston 47 includes seal rings 56 and 57 on its outer peripheral surface and inner peripheral surface, and has a pressing portion 58 that extends toward the friction plates 45 and 46. A return spring 23 is provided between the distal end portion of the cylindrical portion 20 and the spring holder 22 positioned by the snap ring, and the pressing portion 58 is urged away from the friction plate.
[0018]
The first shaft 15 is formed with an oil passage 24 that connects the oil passage 14 of the transmission case 10 and the cylinder 48 across the output gear 16 portion. By supplying pressure oil to the cylinder 48, the piston 47 becomes a friction plate. 45 and 46 are pressed.
[0019]
In the embodiment, the cylinder 48 for the piston 47 that presses the friction plate is formed on the clutch drum 41 side, and the inner peripheral edge of the vertical wall portion 44 of the cylinder is welded to the disk portion 34 of the parking gear 33. As a result, the welded portion is located away from the inner peripheral surface 49 of the outer peripheral wall that is the piston sliding surface, and no welding distortion occurs on the piston sliding surface.
[0020]
Similarly, the clutch drum 41 is welded to the disk portion 34 of the parking gear at the inner peripheral edge of the vertical wall portion 44, and the impact load applied to the parking gear 33 does not directly reach the clutch drum. Therefore, it is necessary to increase the plate thickness of the clutch drum 41. Absent.
Since the parking gear 33 is not formed with a cylinder portion, the parking gear can be thin in the axial direction.
[0021]
An output gear 16 is formed on the first shaft 15 on which the parking gear 33 rotates integrally, and a shoulder 19 having a diameter smaller than the root diameter of the output gear is formed on the side surface thereof. The parking gear 33 is relatively large. Since it is fitted and welded to the shoulder portion 19 of the radius, the coupling strength is high and high rigidity is ensured even if the disk portion of the parking gear is thin.
In the embodiment, the rotation axis is divided into the first axis and the second axis, but the present invention is not limited to this.
[0022]
【The invention's effect】
As described above, according to the present invention, in the coupling portion between the adjacent clutch drum and the parking gear of the automatic transmission, the clutch drum forms a spline portion that engages with the friction plate and a cylinder that accommodates the piston, and its inner peripheral surface. Is provided with an outer peripheral wall portion serving as a sliding surface of the piston and a vertical wall portion extending radially inward from the outer peripheral wall portion, and an inner peripheral edge of the vertical wall portion of the clutch drum is welded to a disk portion of the parking gear. Therefore, the welded portion is separated from the piston sliding surface, and there is an effect that welding distortion does not occur on the piston sliding surface.
[0023]
Similarly, the clutch drum is welded to the disk portion of the parking gear at the inner peripheral edge of the vertical wall portion, and the impact load applied to the parking gear does not directly affect the clutch drum, so that it is not necessary to increase the plate thickness of the clutch drum.
In addition, since the cylinder portion is not formed in the parking gear, the parking gear can be thin in the axial direction. For example, the manufacturing cost can be reduced by manufacturing the parking gear by press molding.
[Brief description of the drawings]
FIG. 1 is a sectional view around a parking gear showing the configuration of an embodiment of the present invention.
FIG. 2 is an enlarged view of a main part of the embodiment.
FIG. 3 is a sectional view around a parking gear showing a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Transmission case 12 Support hole 14, 24 Oil path 15 1st axis | shaft 16 Output gear 17 Outer end 18 Support hole 19 Shoulder part 20 Tube part 21 Outer peripheral surface 22 Spring holder 23 Return spring 25 2nd axis | shaft 30 Bearing 31 Bearing 33 Parking gear 34 Disc part 35 Teeth 36 Recess 40 Clutch mechanism 41 Clutch drum 42 Spline part 43 Outer peripheral wall part 44 Vertical wall part 45, 46 Friction plate 47 Piston 48 Cylinder 49 Inner peripheral surface 50 Rotating member 51 Spline 56, 57 Seal ring 58 Pressing portion 64 Parking gear 66 Cylindrical portion 68 Cylinder portion 71 Clutch drum 77 Piston

Claims (3)

On the rotating shaft of the automatic transmission, a clutch mechanism that presses the friction plate engaged with the clutch drum with a piston and a parking gear are provided adjacent to each other in the axial direction.
The clutch drum forms a spline portion that engages with the friction plate, an outer peripheral wall portion that forms a cylinder that accommodates the piston, and an inner peripheral surface thereof serves as a sliding surface of the piston, and is radially inward from the outer peripheral wall portion. A vertical wall extending toward the
The parking gear is provided with teeth on the outer periphery of the disk portion extending in the radial direction,
A coupling structure of a clutch drum and a parking gear, wherein an inner peripheral edge of the vertical wall portion of the clutch drum is welded to the disk portion of the parking gear. An output gear is formed on the rotating shaft, and a shoulder portion having a diameter smaller than the root diameter of the output gear is formed on the clutch mechanism side.
2. A coupling structure of a clutch drum and a parking gear according to claim 1, wherein the parking gear has an annular shape, and an inner peripheral edge thereof is fitted into the shoulder portion, and is welded to the rotating shaft at the fitting portion. 3. The coupling structure of the clutch drum and the parking gear according to claim 1, wherein the parking gear is press-molded from a plate material.

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