JP2005351362A - Centrifugal cancellation mechanism in automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a centrifugal cancellation piston with high strength. <P>SOLUTION: In this centrifugal cancellation mechanism, the shape of a ring-shaped centrifugal cancellation piston 1 is formed by a cylindrical part 13 and a flange part 10 connected to the end part of the cylindrical part 13. A through hole 12 is formed in the centrifugal cancellation piston 1 on the inner diameter side thereof. Thus, the strength of the centrifugal cancellation piston 1 on the inner diameter side is increased. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a centrifugal hydraulic pressure cancellation mechanism in an automatic transmission that cancels centrifugal hydraulic pressure generated in a piston hydraulic chamber that engages a fastening element.

Conventionally, as a centrifugal hydraulic pressure canceling mechanism in an automatic transmission, for example, there is one described in JP-A-2004-19842.
As shown in FIG. 3, the drum 2A and the hub 60 are fastened by urging the engaging portion 7 with a clutch pressing portion 5A connected to the clutch piston 4A.

The drum 2A is connected to a drum cylindrical portion 22A supported by a cylindrical support portion 30 extending from the case 3, a drum disc portion 20A connected to one end of the drum cylindrical portion 22A, and an outer diameter side of the drum disc portion 20A. The drum cylindrical portion 22A and the drum portion 21A extending in the same direction.
A clutch piston 4A is disposed on the drum cylindrical portion 22A side inside the drum 2A, and a clutch piston oil chamber 23 is formed between the clutch piston 4A and the drum disc portion 20A.

A clutch pressing portion 5A that biases the engaging portion 7 is connected to an outer diameter side edge of the clutch piston 4A.
In the engaging portion 7, friction plates 70 that mesh with the splines of the drum portion 21 </ b> A and friction plates 71 that mesh with the splines of the hub 60 are alternately arranged.

The clutch piston 4 </ b> A moves in a direction in which the engagement portion 7 is urged when the clutch operating oil pressure is supplied to the clutch piston oil chamber 23.
Thereby, the drum 2A and the hub 60 are fastened.

A centrifugal cancel piston 1A is arranged on the side of the clutch piston 4A opposite to the clutch piston oil chamber 23.
The centrifugal cancel piston 1A has an outer diameter side in contact with an inner peripheral surface on the outer diameter side of the clutch piston 4A, and an inner diameter side in contact with an outer peripheral surface of the drum cylindrical portion 22A.
Thereby, the centrifugal cancel oil chamber 40 is formed between the clutch piston 4A and the centrifugal cancel piston 1A.

  Thus, the clutch piston oil chamber 23 and the centrifugal cancel oil chamber 40 are provided on both surfaces of the clutch piston 4A, respectively, and the centrifugal hydraulic pressure (clutch pressing portion 5A) generated by the rotation of the clutch hydraulic oil in the clutch piston oil chamber 23 is provided. Has been canceled by the centrifugal oil pressure generated by the rotation of the centrifugal canceling oil supplied to the centrifugal canceling oil chamber 40.

Further, a notch portion 17 is formed at a predetermined position on the inner peripheral edge of the ring-shaped centrifugal cancel piston 1A.
The notch 17 provides a gap between the inner peripheral edge of the centrifugal cancel piston 1A and the outer peripheral surface of the drum cylindrical portion 22A into which the center hole of the centrifugal cancel piston 1A is fitted.
The centrifugal canceling oil supplied to the centrifugal canceling oil chamber 40 is discharged through the notch 17.
JP 2004-19842 A

  However, when the clutch piston 4A or the centrifugal cancel piston 1A rotates at a high speed, excessive centrifugal hydraulic pressure is generated by the centrifugal cancel oil in the centrifugal cancel oil chamber 40, and a large stress is generated in the centrifugal cancel piston 1A. . Since the notched portion 17 is provided on the inner diameter side of the centrifugal cancel piston 1A, the strength is weak and the centrifugal cancel piston 1A cannot cope with a large stress generated by the centrifugal hydraulic pressure.

  Therefore, in view of such problems, the present invention has an object to provide a high-strength centrifugal cancel piston.

  The present invention relates to a ring-shaped piston that urges an engaging portion of a fastening element when hydraulic pressure is supplied to a piston oil chamber, and a ring-shaped centrifugal cancel piston disposed on the opposite side of the piston from the piston oil chamber. And a centrifugal cancel oil chamber formed between the piston and the centrifugal cancel piston, and automatically canceling centrifugal hydraulic pressure generated in the piston oil chamber by supplying centrifugal cancel oil to the centrifugal cancel oil chamber In a centrifugal hydraulic pressure canceling mechanism in a transmission, the centrifugal canceling piston is composed of a cylindrical portion on the inner side of the ring shape and a flange connected to the end of the cylindrical portion, and the centrifugal canceling piston is arranged on the inner diameter side of the centrifugal canceling piston. A through hole for discharging the centrifugal cancel oil in the oil chamber was provided.

  According to the present invention, the ring-shaped centrifugal cancel piston is constituted by the flange portion and the cylindrical portion, and the through hole is provided on the inner diameter side of the centrifugal cancel piston as a discharge oil passage. Strength is improved.

Next, embodiments of the present invention will be described by way of examples.
FIG. 1 is a sectional view showing a centrifugal hydraulic pressure canceling mechanism in the present embodiment.
A ring-shaped drum disk portion 20, a drum cylindrical portion 22 extending from the inner diameter side end of the drum disk portion 20, and a drum extending in the same direction as the drum cylindrical portion 22 from the outer diameter side end portion of the drum disk portion 20 The drum 2 is configured by the unit 21.
The drum cylindrical portion 22 is rotatably supported by a cylindrical support portion 30 extending from the case 3 in the input shaft direction of the automatic transmission (not shown).

A ring-shaped cylinder is formed on the inner diameter side of the drum 2, and a clutch piston 4 having a substantially U-shaped cross section is fitted into this cylinder with the U-shaped closed side facing the drum disk portion 20 side. .
The first outer peripheral surface 27 of the drum cylindrical portion 22 on the side to which the drum disc portion 20 is connected and the inner peripheral surface of the disc protruding portion 26 protruding inward from the drum disc portion 20 serve as a slide surface with the clutch piston 4. ing.
Accordingly, the clutch piston 4 can slide in the axial direction of the drum cylindrical portion 22 with respect to the drum 2.

A clutch piston oil chamber 23 is formed between the clutch piston 4 and the drum disk portion 20 with the inner diameter side sealed by a seal member 22a and the outer diameter side sealed by a seal member 26a. The clutch hydraulic pressure is supplied from an oil pump or the like through an oil passage 31 provided in the case 3 and a clutch hydraulic oil supply oil passage 24.
From the outer peripheral edge of the clutch piston 4, the clutch pressing portion 5 extends toward an engaging portion 7 described later.
When the clutch operating oil pressure is supplied to the clutch piston oil chamber 23, the clutch pressing portion 5 moves in a direction in which the engaging portion 7 is urged.

On the inner diameter side of the drum portion 21, a planetary gear 6 including a carrier 6 a partially illustrated and a sun gear and a ring gear (not illustrated) is provided.
A friction plate 70 meshing with a spline on the inner diameter side of the drum portion 21 and a friction plate 71 meshing with a spline on the outer diameter side of the hub 60 of the planetary gear 6 are alternately arranged to constitute the engaging portion 7. By energizing the engaging portion 7 by the clutch pressing portion 5, the friction plates 70 and 71 arranged alternately are engaged, and the drum 2 and the hub 60 are fastened.

The drum cylindrical portion 22 has a second outer peripheral surface 28 having a diameter smaller than the diameter of the first outer peripheral surface 27 on the side opposite to the side to which the drum disk portion 20 is connected.
A ring-shaped centrifugal cancel piston 1 is disposed on the inner diameter side of the clutch piston 4, and a seal ring 1 a is provided on the outer peripheral edge side of the centrifugal cancel piston 1, and this seal ring 1 a is an inner diameter side of the clutch piston 4. The inner peripheral edge is in contact with the second outer peripheral surface 28 slidably in contact with the side surface.

A return spring 9 is provided between the clutch piston 4 and the centrifugal cancel piston 1, and the return spring 9 biases the clutch piston 4 toward the drum disk portion 20 and the centrifugal cancel piston 1 toward the planetary gear 6. .
A snap ring 8 is attached to the groove 28a of the second outer peripheral surface 28 of the drum cylindrical portion 22 to restrict the movement of the centrifugal cancel piston 1 to the planetary gear 6 side and the centrifugal cancel piston of the carrier 4 of the planetary gear 6. The movement to 1 side is also regulated.

  Further, a centrifugal cancel oil chamber 40 is formed between the clutch piston 4 and the centrifugal cancel piston 1, and centrifugal cancel oil is supplied to the centrifugal cancel oil chamber 40 from a supply oil passage 25 provided in the drum cylindrical portion 22. Supplied.

When the clutch piston 4, the drum 2, and the centrifugal cancel piston 1 rotate at a high speed, centrifugal hydraulic pressure is generated by the clutch hydraulic oil in the clutch piston oil chamber 23, and the centrifugal hydraulic pressure urges the clutch piston 4 toward the centrifugal cancel piston 1. To do. At the same time, centrifugal oil pressure is generated by the centrifugal canceling oil in the centrifugal cancellation oil chamber 40, and the clutch piston 4 is urged toward the drum disk portion 20 by the centrifugal oil pressure.
The centrifugal hydraulic pressure caused by the clutch operating oil in the clutch piston oil chamber 23 can be offset by the centrifugal hydraulic pressure caused by the centrifugal canceling oil in the centrifugal cancellation oil chamber 40.

Next, details of the centrifugal cancel piston will be described.
FIG. 2 is an enlarged cross-sectional view showing the centrifugal cancel piston 1.
The centrifugal cancel piston 1 includes a cylindrical portion 13 that is aligned with the second outer peripheral surface 28 of the drum cylindrical portion 22, a ring-shaped flange portion 10 that extends to the outer peripheral side of the cylindrical portion 13, and an end of the cylindrical portion 13 on the planetary gear 6 side. And a connecting portion 11 connecting the inner peripheral edge of the flange portion 10.

The cylindrical portion outer peripheral surface 14 of the cylindrical portion 13 and the surface of the connecting portion 11 on the centrifugal cancel oil chamber 40 side form a predetermined inclination, and the surface of the connecting portion 11 on the centrifugal cancel oil chamber 40 side and the flange portion 10 The surface on the centrifugal canceling oil chamber 40 side forms a predetermined inclination.
Further, the surface of the flange portion 10 on the centrifugal cancel oil chamber 40 side and the outer peripheral surface 14 of the cylindrical portion are substantially perpendicular.

A through hole 12 is provided at a predetermined position in the circumferential direction of the connecting portion 11 as a discharge oil passage for discharging the oil in the centrifugal cancel oil chamber 40.
Here, the opening edge of the through hole 12 on the centrifugal cancel oil chamber 40 side is referred to as an oil chamber side opening edge 15, and the opening edge on the planetary gear 6 side is referred to as an outer opening edge 16.
The edge of the oil chamber side opening edge 15 on the second outer peripheral surface 28 side is on the outer diameter side of the cylindrical portion outer peripheral surface 14, and the edge of the outer opening edge 16 on the second outer peripheral surface 28 side is inner diameter of the cylindrical portion outer peripheral surface 14. With respect to the outer peripheral surface 14 of the cylindrical portion so that the outer diameter side edge of the outer opening edge 16 is closer to the inner diameter side than the outer diameter side edge of the oil chamber side opening edge 15. The through hole 12 is provided obliquely and perpendicular to the connecting portion 11.

  Further, the centrifugal cancel piston 1 forms a flange portion 10, a connecting portion 11, and a cylindrical portion 13 by pressing a ring-shaped plate, and then forms a through hole 12 by drilling.

  The centrifugal canceling oil supplied from the supply oil passage 25 into the centrifugal canceling oil chamber 40 cancels out the centrifugal hydraulic pressure caused by the clutch hydraulic oil in the clutch piston oil chamber 23, and the through hole is used during the stroke of the clutch piston 4 or the like. 12 is discharged.

  The present embodiment is configured as described above, and the ring-shaped centrifugal cancel piston 1 is composed of a cylindrical portion 13 and a flange portion 10 connected via a connecting portion 11 formed at an end of the cylindrical portion 13. By configuring and forming the through hole 12 in the connecting portion 11, the strength on the inner diameter side of the centrifugal cancel piston 1 can be improved. (Effects corresponding to claim 1)

Further, the through hole 12 has an edge on the second outer peripheral surface 28 side of the oil chamber side opening edge 15 on the outer diameter side of the cylindrical portion outer peripheral surface 14, and an edge on the second outer peripheral surface 28 side of the outer opening edge 16 on the cylindrical portion. Provided in the connecting portion 11 so that the outer diameter side edge of the outer opening edge 16 is located on the inner diameter side of the outer circumferential surface 14 and the outer diameter side edge of the outer opening edge 16 than the outer diameter side edge of the oil chamber side opening edge 15. .
Thus, by providing the through hole 12 obliquely with respect to the outer peripheral surface 14 of the cylindrical portion, the effective area of the centrifugal cancel oil chamber 40 is secured to the inner diameter side while improving the strength on the inner diameter side of the centrifugal cancel piston 1. can do. (Effects corresponding to claim 2)

  Furthermore, for example, if an effective area of the same centrifugal cancel piston as in this embodiment is obtained by forming a through hole parallel to the cylindrical portion, the hole is processed from the right direction in FIG. At this time, when the drill or the like penetrates the connecting part during drilling, the cylindrical part is processed using only a part of the drill, so the drill tip escapes to the outside or breaks. Processing is very difficult. However, in the present embodiment, since the oblique through holes 12 are formed after the press working, the working is not performed using only a part of the drill, and the hole working becomes easy. Moreover, the connecting portion 11 that connects the cylindrical portion 13 formed parallel to the axis and the flange portion 10 formed perpendicularly is formed obliquely, and the through hole 12 is formed in the connecting portion 11. Drilling becomes even easier. Further, by performing the hole processing after the press processing, the position accuracy of the holes can be increased, and the transmission performance of the automatic transmission can be improved.

  In this embodiment, the centrifugal cancel piston 1 is formed by pressing the flange portion 10, the connecting portion 11 and the cylindrical portion 13, and then the through hole 12 is formed by drilling. After providing the through hole 12 in the plate material, the flange portion 10, the connecting portion 11 and the cylindrical portion 13 may be formed by pressing, and the edge on the second outer peripheral surface 28 side of the oil chamber side opening edge 15 is The same position as the outer peripheral surface 14 of the cylindrical portion may be used.

It is sectional drawing which shows the Example in this invention. It is sectional drawing which shows a centrifugal cancellation piston. It is sectional drawing which shows the conventional hydraulic cancellation structure.

Explanation of symbols

1 Centrifugal cancellation piston 2 Drum (fastening element)
3 Case 4 Clutch piston (piston)
5 Clutch pressing part 6 Planetary gear 7 Engaging part (fastening element)
DESCRIPTION OF SYMBOLS 8 Snap ring 9 Return spring 10 Flange part 11 Connection part 12 Through-hole 13 Cylindrical part 14 Cylindrical part outer peripheral surface 15 Oil chamber side opening edge 16 Outer opening edge 17 Notch part 20 Drum disc part 21 Drum part 22 Drum cylindrical part 23 Clutch Piston oil chamber (piston oil chamber)
24 Clutch hydraulic oil supply oil passage 25 Supply oil passage 26 Disc protrusion 27 First outer peripheral surface 28 Second outer peripheral surface 30 Cylindrical support portion 31 Oil passage 40 Centrifugal cancellation oil chamber 60 Hub (fastening element)
70, 71 Friction plate

Claims (2)

A ring-shaped piston that urges the engaging portion of the fastening element when hydraulic pressure is supplied to the piston oil chamber; a ring-shaped centrifugal cancel piston disposed on the opposite side of the piston from the piston oil chamber; An automatic transmission comprising a centrifugal canceling oil chamber formed between the piston and the centrifugal canceling piston, and supplying the centrifugal canceling oil to the centrifugal canceling oil chamber to offset the centrifugal hydraulic pressure generated in the piston oil chamber. In the centrifugal hydraulic canceling mechanism in the machine,
The centrifugal cancel piston is composed of a cylindrical portion on the inner diameter side of the ring shape, and a flange portion connected to an end portion of the cylindrical portion,
A centrifugal hydraulic pressure canceling mechanism in an automatic transmission, wherein a through hole for discharging centrifugal canceling oil in the centrifugal canceling oil chamber is provided on an inner diameter side of the centrifugal canceling piston. The through-hole has an opening edge on the centrifugal cancel oil chamber side, the edge on the ring shape center side of the centrifugal cancel piston is located on the outer diameter side of the outer peripheral surface of the cylindrical portion,
At the other opening edge, the edge on the ring shape center side of the centrifugal cancel piston is located on the inner diameter side with respect to the outer peripheral surface of the cylindrical portion, and the other is located on the other side than the outer diameter side edge in the opening on the centrifugal cancel oil chamber side 2. The centrifugal hydraulic pressure canceling mechanism for an automatic transmission according to claim 1, wherein the outer diameter side edge of the opening is positioned on the inner diameter side.

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