JP5349537B2 - Brake mechanism - Google Patents

Description

  The present invention relates to a brake mechanism that can be applied to an automatic transmission or the like and can lock a rotating element to a case by pressing a friction plate and a friction counterpart plate with a piston member.

  Conventionally, the brake housing 40 in which the third brake B3 is disposed is configured separately from the case 26 in which the first brake B1 is disposed, and the distal end of the first fitting portion 42 of the third brake B3 is The second brake 78 is opposed to the tip of the second fitting portion 70 of the first brake B1 with a slight gap, and the friction plate 74 and the friction counterpart plate 72 of the first brake B1 are clamped between the second piston 78. A tandem type frictional engagement device that functions as a stopper member is known (for example, Patent Document 1).

JP 2004-278562 A

  However, in the brake mechanism disclosed in Patent Document 1, the brake housing 40 to which the friction mating plate 44 is spline-fitted is fixed to the second case member 36 by the bolt 39. There is a problem that the number of parts increases to secure the case.

  The present invention has been made paying attention to the above problem, and provides a brake mechanism capable of ensuring case fixing of the second connecting member to which the friction counterpart plate is spline-fitted while suppressing an increase in the number of parts. The purpose is to do.

In order to achieve the above object, the present invention is a brake mechanism capable of locking a rotating element, and includes a first connecting member, a second connecting member, a stopper member, a piston member, and an elastic member. .
The first connecting member is connected to the rotating element, and the friction plate is spline-fitted so as not to be relatively rotatable.
The second connecting member is spline-fitted to the case housing the rotating element so as not to be relatively rotatable, and the friction counterpart plate is spline-fitted to be relatively unrotatable.
The stopper member restricts movement of the second connecting member to one side.
The piston member is provided to be able to press the friction counterpart plate toward the one side.
The elastic member, the disposed between the second coupling member and the piston member, wherein a biasing force to the one side occurred with respect to the second coupling member, of the one side relative to the piston member A biasing force to the other side in the reverse direction is generated.
And it was set as the structure which makes the urging | biasing force of the said elastic member act on both the one side which presses the said 2nd connection member against the said stopper member, and the other side which returns the said piston member to an original position.

As described above, since the second connecting member that locks the rotating element is spline-fitted to the case, a fastening component such as a bolt that fixes the second connecting member is not required.
However, if the second connecting member is simply spline fitted to the case, the spline fitting between the second connecting member and the case may be lost. When such a spline fitting disconnection occurs, dragging occurs between the friction plate and the friction counterpart plate even when the piston is not pressed.
In contrast, in the present invention, an elastic member is disposed between the second connecting member and the piston member, and the biasing force of the elastic member is applied to the one side that presses the second connecting member against the stopper member , and the piston member is moved back to the original position. The structure which acts on both the other side which returns to a position is employ | adopted. In other words, the elastic member that returns the piston member to the position where the pressing of the friction plate and the friction counterpart plate is released is also used as a removal preventing member that prevents the second connecting member that is spline-fitted to the case from coming off. For this reason, an additional component for preventing the second connecting member that is spline-fitted to the case from being detached is unnecessary.
As a result, it is possible to ensure case fixing of the second connecting member to which the friction counterpart plate is spline-fitted while suppressing an increase in the number of parts.

1 is a longitudinal sectional view showing an overall configuration of an automatic transmission to which a brake mechanism according to a first embodiment is applied. It is a skeleton figure which shows the automatic transmission to which the brake mechanism of Example 1 was applied. It is a fastening operation | movement table | surface figure which shows the fastening operation | movement of the 4th forward speed and the reverse 1st speed by the combination of two simultaneous fastening among five frictional engagement elements in the automatic transmission to which the brake mechanism of Example 1 was applied. It is a detailed sectional view showing the rear side farther from the drive source than the output gear in the automatic transmission to which the brake mechanism of the first embodiment is applied. It is a detailed sectional view showing the front side closer to the drive source than the output gear in the automatic transmission to which the brake mechanism of the first embodiment is applied. FIG. 6 is an enlarged cross-sectional view illustrating a peripheral configuration of a fifth brake that is the brake mechanism of the first embodiment. FIG. 6 is a shift operation explanatory diagram showing a skeleton diagram (a) and a speed diagram (b) at a first speed (1st) shift stage in the automatic transmission to which the brake mechanism of the first embodiment is applied. FIG. 6 is an explanatory diagram showing a shift operation showing a skeleton diagram (a) and a speed diagram (b) at the second speed (2nd) in the automatic transmission to which the brake mechanism of the first embodiment is applied. FIG. 6 is a shift operation explanatory diagram showing a skeleton diagram (a) and a speed diagram (b) at a third speed (3rd) in the automatic transmission to which the brake mechanism of the first embodiment is applied. FIG. 6 is a shift operation explanatory diagram showing a skeleton diagram (a) and a speed diagram (b) at a fourth speed (4th) in the automatic transmission to which the brake mechanism of the first embodiment is applied. FIG. 5 is a shift operation explanatory diagram showing a skeleton diagram (a) and a speed diagram (b) at a reverse speed (Rev) in the automatic transmission to which the brake mechanism of the first embodiment is applied. FIG. 3 is a torque sharing ratio table showing torque sharing ratios of frictional engagement elements at each gear stage in the automatic transmission to which the brake mechanism of the first embodiment is applied.

  Hereinafter, the best mode for realizing the brake mechanism of the present invention will be described based on Example 1 shown in the drawings.

First, the configuration will be described.
The configuration of the automatic transmission to which the brake mechanism of the first embodiment is applied includes “overall configuration”, “transmission configuration”, “rear-side arrangement friction engagement element configuration”, “front-side arrangement friction engagement element configuration”, “ The description will be divided into “the peripheral configuration of the fifth brake”.

[overall structure]
FIG. 1 is a longitudinal sectional view showing an overall configuration of an automatic transmission to which the brake mechanism of the first embodiment is applied. FIG. 2 is a skeleton diagram showing the automatic transmission to which the brake mechanism of the first embodiment is applied. is there. Hereinafter, the planetary gear configuration and the frictional engagement element configuration of the automatic transmission will be described with reference to FIGS. 1 and 2.

  As shown in FIGS. 1 and 2, the automatic transmission to which the brake mechanism of the first embodiment is applied includes a Ravigneaux planetary gear PGU, an input shaft IN, an output gear OUT, a first clutch 13R / C, A second clutch 234 / C, a third brake 12 / B, a fourth brake 4 / B, a fifth brake R / B, and an automatic transmission case ATC are provided.

The Ravigneaux planetary gear PGU is a composite planetary gear in which a single-pinion planetary gear and a double-pinion planetary gear, which are two rows of planetary gears, are integrated. As shown in FIGS. 1 and 2, the Ravigneaux planetary gear PGU includes a front sun gear Ss, a rear sun gear Sd, a ring gear R, a long pinion P _L that meshes with the front sun gear Ss and the ring gear R, and a rear sun gear Sd. It has a short pinion P _S meshing with the long pinion P _L, a common carrier C rotatably supporting the long pinion P _L and the short pinion P _S, a.

  The input shaft IN is a shaft to which rotational drive torque from an engine (drive source) (not shown) is input via a torque converter T / C with a lock-up clutch as shown in FIG. A front sun gear shaft FS is provided coaxially with the input shaft IN, and a front sun gear Ss of a Ravigneaux type planetary gear PGU is spline-fitted to the front sun gear shaft FS.

  The output gear OUT is always connected to the ring gear R as shown in FIG. The output rotation of the output gear OUT is transmitted to the counter gear 1 → the counter shaft 2 → the final reduction gear 3 → the drive gear 4 → the differential gear case 5. The output rotation transmitted to the differential gear case 5 passes through the pinion mate shaft 6 → pinions 7 and 7 which rotate integrally with the differential gear case 5, and from the pair of side gears 8 and 9 meshing with the pinions 7 and 7 It is transmitted to the left and right drive shafts and the left and right drive wheels.

  The first clutch 13R / C selectively connects the input shaft IN and the front sun gear Ss (= front sun gear shaft FS) at the first speed (1st), the third speed (3rd), and the reverse speed (Rev). It is a plate friction engagement clutch.

  The second clutch 234 / C is a multi-plate friction engagement clutch that selectively connects the input shaft IN and the common carrier C at the second speed (2nd), the third speed (3rd), and the fourth speed (4th). .

  The third brake 12 / B is a multi-plate friction engagement brake that selectively fixes the rear sun gear Sd to the automatic transmission case ATC at the first speed (1st) and the second speed (2nd).

  The fourth brake 4 / B is a multi-plate friction engagement brake that selectively fixes the front sun gear Ss (= front sun gear shaft FS) to the automatic transmission case ATC at the fourth speed (4th).

  The fifth brake R / B is a multi-plate friction engagement brake that selectively fixes the common carrier C to the automatic transmission case ATC at the reverse speed (Rev).

  As shown in FIG. 1, the automatic transmission case ATC includes a Ravigneaux planetary gear PGU and five frictional engagement elements 13R / C, 234 / C, 12 / B, 4 / B, R / B, etc. Is housed. A converter housing 10 is connected to the drive source side of the automatic transmission case ATC, and a torque converter T / C is disposed in the converter housing 10. In addition, an oil pump O / P that is rotationally driven by an engine (drive source) is disposed at a connecting portion between the automatic transmission case ATC and the converter housing 10.

[Speed change configuration]
FIG. 3 shows a fastening operation table for achieving the fourth forward speed and the first reverse speed by combining two of the five frictional engagement elements in the brake mechanism of the first embodiment. Hereinafter, based on FIG. 3, a description will be given of a shift configuration that establishes each shift stage of the brake mechanism of the first embodiment.

  As shown in FIG. 3, the first speed (1st) shift stage is configured such that the input shaft IN and the front sun gear Ss are connected by the simultaneous engagement of the first clutch 13R / C and the third brake 12 / B, and the rear sun gear Sd is connected. Achieved by fixing the case.

  As shown in FIG. 3, the second speed (2nd) shift stage connects the input shaft IN and the common carrier C by simultaneously engaging the second clutch 234 / C and the third brake 12 / B, and the rear sun gear Sd. Achieved by fixing the case.

  As shown in FIG. 3, the third speed (3rd) is connected to the input shaft IN, the front sun gear Ss, and the common carrier C by simultaneously engaging the first clutch 13R / C and the second clutch 234 / C. To achieve.

  As shown in FIG. 3, the fourth speed (4th) shift stage connects the input shaft IN and the common carrier C by simultaneous engagement of the second clutch 234 / C and the fourth brake 4 / B, and the front sun gear Ss. This is achieved by fixing the case.

  As shown in FIG. 3, the reverse speed (Rev) shift stage connects the input shaft IN and the front sun gear Ss by simultaneous engagement of the first clutch 13R / C and the fifth brake R / B, and the common carrier C is connected. Achieved by fixing the case.

  As is apparent from the engagement operation table of FIG. 3, the up-shift and the down-shift at the adjacent gears from the first speed (1st) to the fourth speed (4th) are so-called two friction engagement elements. This is done by shifting. Here, the change gear shift means that one of the two friction engagement elements that are simultaneously engaged in the gear stage before the shift is maintained in the engaged state, and the other friction engagement element is released. This means that one frictional engagement element is newly engaged to shift to the gear stage after the shift. For example, in the upshift from the first speed (1st) to the second speed (2nd), the third brake 12 / B is maintained in the engaged state, the first clutch 13R / C is released, and the second clutch 234 / This is done by signing C.

[Friction fastening element configuration at rear side]
As shown in FIGS. 1 and 2, the five frictional engagement elements have a front region closer to the drive source than the output gear OUT and a rear region farther from the drive source than the output gear OUT, with the output gear OUT as a boundary. It is divided and arranged. Hereinafter, based on FIG. 4, the configuration of the frictional engagement element disposed in the rear region farther from the drive source than the output gear OUT will be described.

  As shown in FIG. 4, in the rear region far from the drive source than the output gear OUT, there is a Ravigneaux planetary gear PGU, the third brake 12 / B, and the fourth brake 4 in the internal space of the automatic transmission case ATC. Two friction fastening elements of / B are arranged.

  The output gear OUT is supported on the cylindrical portion 21 b of the intermediate wall 21 via a bearing 22. The intermediate wall 21 is disposed on the front side of the output gear OUT, and is connected to the automatic transmission case ATC. The wall portion 21a extends in the radial direction, and the cylindrical portion extends from the wall portion 21a to the rear side in the axial direction. 21b. Note that the rear side of the output gear OUT is always connected to the ring gear R, and the front side is always connected to the parking gear 23. A parking pole 24 is disposed in the parking gear 23 so as to be able to mesh with it.

The Ravigneaux type planetary gear PGU is disposed at a position adjacent to the rear side of the output gear OUT and at the outer peripheral position of the front sun gear shaft FS. The outer diameter of the Ravigneaux planetary gear PGU is defined by the outer diameter of the ring gear R, and the axial dimension of the Ravigneaux planetary gear PGU is defined by the axial length of the common carrier C. The front sun gear Ss is spline-coupled to the outer peripheral position of the front sun gear shaft FS, and the rear sun gear Sd is rotatably supported. Common carrier C, the front supporting the long pinion shaft 25 for supporting the long pinion P _L, the short pinion shaft 26 which supports the short pinion P _S (see FIG. 1), the two pinion shafts 25 and 26 at both end positions The carrier plate 27 and the rear carrier plate 28 are configured.

  The third brake 12 / B is arranged at a radially outer peripheral position from the Ravigneaux planetary gear PGU and at a position overlapping the Ravigneaux planetary gear PGU in the radial direction. The four friction plates 36 of the third brake 12 / B are spline-fitted to the outer peripheral side of the second hub member 29 that is splined to the rear sun gear Sd through the rear side of the common carrier C. The four friction counterpart plates 37 of the third brake 12 / B are spline-fitted to the automatic transmission case ATC. The third brake piston 30 of the third brake 12 / B is on the rear side of the third brake 12 / B by the friction plates 36 and the friction counterpart plates 37 that are alternately arranged, and the automatic transmission case ATC and the inside thereof. And an axially projecting case 31, and is disposed in a piston cylinder having a large annular groove formed by the axially protruding case portion 31. A third brake return spring 32 is interposed between the automatic transmission case ATC and the third brake piston 30.

  The fourth brake 4 / B is disposed at a position radially inward of the third brake 12 / B and overlapping with the third brake piston 30 in the radial direction. The two friction plates 38 of the fourth brake 4 / B are arranged on the outer peripheral side of the third hub member 33 splined to the front sun gear shaft FS passing through the rear side of the second hub member 29 and the inner peripheral side of the rear sun gear Sd. Splined. The two friction mating plates 39 of the fourth brake 4 / B are spline-fitted to the axial projecting case portion 31. The fourth brake piston 34 of the fourth brake 4 / B is disposed on the rear side of the fourth brake 4 / B and in a small annular groove piston cylinder formed by the automatic transmission case ATC. A fourth brake return spring 35 is interposed between the automatic transmission case ATC and the fourth brake piston 34.

  As described above, the automatic transmission case ATC has a shape corresponding to the layout of the output gear OUT, the Ravigneaux planetary gear PGU, the third brake 12 / B, and the fourth brake 4 / B. That is, as shown in FIG. 4, the case diameter is gradually reduced from the case diameter Df at the position of the output gear OUT toward the position of the third brake 12 / B, and the third brake piston 30 and the fourth brake 4 / B are thereby narrowed down. The case diameter Dr (<Df) on the rear end side where is arranged is set to a small diameter.

[Friction fastening element configuration on the front side]
As shown in FIGS. 1 and 2, the five frictional engagement elements have a front region closer to the drive source than the output gear OUT and a rear region farther from the drive source than the output gear OUT, with the output gear OUT as a boundary. It is divided and arranged. Hereinafter, based on FIG. 5, the configuration of the frictional engagement element disposed in the front region closer to the drive source than the output gear OUT will be described.

  As shown in FIG. 5, in the area closer to the drive source than the output gear OUT, there is a first clutch 13R / C, a second clutch 234 / C, and a fifth brake in the internal space of the automatic transmission case ATC. Three frictional engagement elements of R / B are arranged. The radial arrangement relationship of these three frictional engagement elements is that the fifth brake R / B is arranged on the outer side in the radial direction, the second clutch 234 / C is arranged on the inner side in the radial direction from the fifth brake R / B, and The first clutch 13R / C is arranged radially inward from the two clutch 234 / C.

  As shown in FIG. 5, the fifth brake R / B is disposed at the outermost peripheral position among the three frictional engagement elements disposed in the front side region closer to the drive source than the output gear OUT. The three friction plates 60 of the fifth brake R / B are splined on the outer peripheral side of the first drum member 41 connected via the cylindrical connecting plate 40 to the front carrier plate 27 at the front end of the common carrier C. Mated. The three friction counterpart plates 61 and the retaining plate 62 of the fifth brake R / B are spline-fitted to the fifth brake drum 42 fixed to the wall portion 21a of the intermediate wall 21. The fifth brake piston 43 of the fifth brake R / B is disposed in a piston cylinder having an annular groove formed in a partition wall 44 fixed to the automatic transmission case ATC, on the front side of the fifth brake R / B. A fifth brake return spring 45 is interposed between the fifth brake drum 42 and the fifth brake piston 43.

  As shown in FIG. 5, the second clutch 234 / C is located radially inward of the fifth brake R / B, and at least partially overlaps the fifth brake R / B in the radial direction. Placed in. The three friction plates 63 of the second clutch 234 / C are spline-fitted to the outer peripheral side of the second drum member 46 connected and fixed to the input shaft IN by spline coupling. The three friction mating plates 64 and the retaining plate 65 of the second clutch 234 / C are splined to the inner peripheral side of the first drum member 41. The second clutch piston 47 of the second clutch 234 / C is disposed on the piston cylinder formed on the first drum member 41 on the rear side of the second clutch 234 / C. A second clutch return spring 48 is interposed between the first drum member 41 and the second clutch piston 47. That is, the first drum member 41 is a dual-purpose drum member in which the second clutch 234 / C is disposed on the inner peripheral side and the fifth brake R / B is disposed on the outer peripheral side.

  As shown in FIG. 5, the first clutch 13R / C is located radially inward of the second clutch 234 / C, and at least partially overlaps the second clutch 234 / C in the radial direction. Placed in. The three friction plates 66 of the first clutch 13R / C are splined on the outer peripheral side of the first hub member 49 that passes through the inner peripheral side of the first drum member 41 and is connected to the front sun gear Ss via the front sun gear shaft FS. Mated. The three friction counterpart plates 67 and the retaining plate 68 of the first clutch 13R / C are spline-fitted to the inner peripheral side of the second drum member 46 that is connected and fixed to the input shaft IN by spline coupling. The first clutch piston 50 of the first clutch 13R / C is disposed on the piston cylinder formed on the second drum member 46 on the front side of the first clutch 13R / C. A first clutch return spring 51 is interposed between the second drum member 46 and the first clutch piston 50. That is, the second drum member 46 is a dual-purpose drum member in which the first clutch 13R / C is disposed on the inner peripheral side and the second clutch 234 / C is disposed on the outer peripheral side.

  As described above, the three frictional engagement elements arranged in the front region closer to the drive source than the output gear OUT are set to have the following relationship. The outer diameters of the friction plate 66 and the friction counterpart plate 67 of the first clutch 13R / C are made smaller than the inner diameters of the friction plate 63 and the friction counterpart plate 64 of the second clutch 234 / C. The outer diameters of the friction plate 63 and the friction counterpart plate 64 of the second clutch 234 / C are made smaller than the inner diameters of the friction plate 60 and the friction counterpart plate 61 of the fifth brake R / B. The friction plate 66 of the first clutch 13R / C, the friction plate 63 of the second clutch 234 / C, and the friction plate 60 of the fifth brake R / B are set to the same number of three. Similarly, the friction counter plate 67 of the first clutch 13R / C, the friction counter plate 64 of the second clutch 234 / C, and the friction counter plate 61 of the fifth brake R / B are set to the same number of three. Yes.

  In the present specification, the “friction plate” refers to a clutch plate or a brake plate that is fitted to a spline provided on the outer periphery of the drum member or the hub member. The “friction plate” may have a friction material affixed on both sides or a friction material affixed only on one side. The “friction mating plate” refers to a clutch plate or a brake plate that fits with a spline provided on the inner periphery of the drum member or the hub member. The “friction mating plate” may not have a friction material attached thereto, or may have a friction material attached thereto.

[Fifth brake peripheral configuration]
FIG. 6 shows a peripheral configuration of a fifth brake R / B that is the brake mechanism of the first embodiment. Hereinafter, the peripheral configuration of the fifth brake R / B will be described in detail based on FIG.

  The fifth brake R / B is a brake mechanism capable of locking the common carrier C (rotating element) to the automatic transmission case ATC. As shown in FIG. 6, the first drum member 41 (first connecting member) ), A fifth brake drum 42 (second connecting member), an intermediate wall 21 (stopper member), a fifth brake piston 43 (piston member), and a fifth brake return spring 45 (elastic member). Prepare.

  The first drum member 41 is connected to the front carrier plate 27 of the common carrier C through a cylindrical connection plate 40. The three friction plates 60 are spline-fitted to the splines provided on the outer periphery of the first drum member 41 so as not to rotate relative to each other.

  The fifth brake drum 42 is provided by being spline-fitted to a spline 21c provided on the intermediate wall 21 connected to an automatic transmission case ATC (case) that accommodates the common carrier C so as not to be relatively rotatable. . Three friction mating plates 61 and one retaining plate 65 are spline-fitted to the splines provided on the inner periphery of the fifth brake drum 42 so as not to rotate relative to each other. Further, the fifth brake drum 42 is provided with a snap ring 69 on the rear side of the friction plate 60 and the friction counterpart plate 61, and a snap ring 70 on the front side of the friction plate 60 and the friction counterpart plate 61. It has been. The snap ring 70 receives a reaction force of the fifth brake return spring 45 for returning the fifth brake piston 43.

  The intermediate wall 21 is configured such that a drum bottom 42a bent inward from the rear side of the fifth brake drum 42 is brought into contact with the drum contact surface 21d of the wall 21a, whereby one side of the fifth brake drum 42 is provided. Restricts movement in the direction of arrow E. The intermediate wall 21 is a case-side member connected and fixed to the automatic transmission case ATC, and has a wall portion 21a extending in the radial direction.

  The fifth brake piston 43 is disposed in a piston cylinder having an annular groove formed in a partition wall 44 fixed to the automatic transmission case ATC. Of the friction plates 60 and the friction counterpart plate 61 arranged alternately, the friction counterpart plate 61 on the other side (arrow F direction side) is provided so as to be able to be pressed to one side (arrow E direction side). The fifth brake piston 43 is provided with a spring support plate 71, which, like the snap ring 70, receives the reaction force of the fifth brake return spring 45 for returning the fifth brake piston 43. receive.

  The fifth brake return spring 45 is disposed between a snap ring 70 provided on the fifth brake drum 42 and a spring support plate 71 provided on the fifth brake piston 43. That is, the fifth brake return spring 45 generates a biasing force to one side (arrow E direction side) with respect to the fifth brake drum 42, and is in the reverse direction on one side with respect to the fifth brake piston 43. It is arranged to generate a biasing force toward the other side (arrow F direction side).

Next, the operation will be described.
The “shifting action at each gear stage” in the automatic transmission to which the brake mechanism of the first embodiment is applied will be described. Next, the operation of the brake mechanism of the first embodiment will be described by dividing it into “necessity of fifth brake drum” and “drum holding operation of fifth brake”.

[Shifting action at each gear stage]
The Ravigneaux planetary gear PGU of the first embodiment includes a front sun gear Ss, a rear sun gear Sd, a ring gear R, and a common carrier C as four rotating elements whose rotational speed relationships are arranged in a straight line on the speed diagram. Hereinafter, based on FIG. 7 to FIG. 11, a description will be given of a shifting operation at each shift stage obtained by making the rotational speed relationships of the four rotating elements different.

(First gear)
At the first speed (1st), the first clutch 13R / C and the third brake 12 / B are simultaneously engaged as shown in the hatching of FIG. 7 (a), and the third brake 12 / B is engaged. The rear sun gear Sd is fixed to the automatic transmission case ATC.
Therefore, when the input rotational speed is inputted to the front sun gear Ss after passing through the input shaft IN, the front sun gear Ss, the common carrier C, the ring gear R, and the like are fixed by fixing the rear sun gear Sd as shown in FIG. The rotational speed relationship of the rear sun gear Sd is defined by one straight line. That is, the rotation speed of the common carrier C is decelerated from the front sun gear Ss, and the rotation speed of the ring gear R is further decelerated from the common carrier C. In this way, the rotational speed of the ring gear R that has been decelerated from the input rotational speed to the front sun gear Ss is transmitted as it is to the output gear OUT, and the first speed gear stage (first underdrive gear stage) is achieved.

(2nd gear)
At the second speed (2nd), as shown in FIG. 8 (a), the second clutch 234 / C and the third brake 12 / B are simultaneously engaged, and the third brake 12 / B is engaged. The rear sun gear Sd is fixed to the automatic transmission case ATC.
Therefore, when the input rotational speed is input to the common carrier C after passing through the input shaft IN, the rotation of the common carrier C, the ring gear R, and the rear sun gear Sd is achieved by fixing the rear sun gear Sd as shown in FIG. The speed relationship is defined by one straight line. That is, the rotation speed of the ring gear R is decelerated from the common carrier C. In this way, the rotational speed of the ring gear R, which has been decelerated from the input rotational speed to the common carrier C, is transmitted as it is to the output gear OUT, and the second speed gear stage (second underdrive gear stage) is achieved.

(3rd speed)
At the third speed (3rd), the first clutch 13R / C and the second clutch 234 / C are simultaneously engaged as shown by hatching in FIG.
Therefore, when the input rotational speed is input to the front sun gear Ss and the common carrier C after passing through the input shaft IN, as shown in FIG. 9B, the front sun gear which is the three rotational elements of the Ravigneaux planetary gear PGU2 Ss, common carrier C, and ring gear R rotate together. In this way, the rotation speed (= input rotation speed) of the ring gear R that is the same as the input rotation speed to the front sun gear Ss and the common carrier C is transmitted to the output gear OUT as it is, and the third speed (direct drive speed) ) Is achieved.

(4th gear)
At the fourth speed (4th), as shown in FIG. 10 (a), the second clutch 234 / C and the fourth brake 4 / B are simultaneously engaged, and the fourth brake 4 / B is engaged. The front sun gear Ss is fixed to the automatic transmission case ATC.
Therefore, when the input rotation speed is input to the common carrier C after passing through the input shaft IN, the front sun gear Ss, the common carrier C, and the ring gear R are fixed by fixing the front sun gear Ss as shown in FIG. Is defined by one straight line. That is, the rotational speed of the ring gear R is increased more than the rotational speed of the common carrier C (= input rotational speed). In this way, the rotational speed of the ring gear R, which is increased in the input rotational speed to the common carrier C, is transmitted as it is to the output gear OUT, and the fourth speed (overdrive speed) is achieved.

(Reverse speed shift stage)
At the reverse speed (Rev), the first clutch 13R / C and the fifth brake R / B are engaged at the same time as shown in FIG. The carrier C is fixed to the automatic transmission case ATC.
Therefore, when the input rotation speed is input to the front sun gear Ss after passing through the input shaft IN, the front sun gear Ss, the common carrier C, and the ring gear R are fixed by fixing the common carrier C as shown in FIG. Is defined by one straight line. That is, the rotation of the ring gear R is decelerated in the direction opposite to the input rotation direction of the front sun gear Ss. In this way, the rotational speed of the ring gear R obtained by reversing and decelerating the input rotational speed to the front sun gear Ss is directly transmitted to the output gear OUT, and a reverse speed gear stage (reverse gear stage) is achieved.

[Necessity of fifth brake drum]
In the first embodiment, the brake mechanism of the present invention is adopted for the fifth brake R / B. Regarding the necessity of the fifth brake drum 42, “why the fifth brake drum 42 is necessary in the first place”. explain.

First, even if it is going to hold | maintain the friction counterplate of a 5th brake with an automatic transmission case, a spline cannot necessarily be formed in the case side over the perimeter of a 5th brake. Therefore, some splines of the friction counterpart plate may not be able to be spline fitted to the automatic transmission case. In this case, there is a possibility that the friction partner plate is not sufficiently held when the fifth brake is engaged, and a large torque cannot be transmitted.
In addition, if the friction brake plate of the fifth brake is held by the automatic transmission case, the outer diameter of the fifth brake becomes unnecessarily large, which increases the members such as the hub, increasing the weight and increasing the cost. End up.

  On the other hand, by providing the fifth brake drum 42, it is possible to form a spline that meshes with the friction counterpart plate 61 of the fifth brake R / B over the entire circumference of the fifth brake drum 42. That is, the friction counterpart plate 61 can be sufficiently held when the fifth brake R / B is engaged, as compared with the case where the fifth brake friction counterpart plate is held by the automatic transmission case. In addition, since the outer diameter of the fifth brake R / B is suppressed to be smaller than when the friction counterpart plate of the fifth brake is held by the automatic transmission case, an increase in weight and an increase in cost can be suppressed.

As described above, the fifth brake R / B is provided with the fifth brake drum 42 for the following two points.
(1) Even if it is intended to hold the friction counterpart plate 61 of the fifth brake R / B with the automatic transmission case ATC, it is not always possible to form a spline in the automatic transmission case ATC over the entire circumference of the fifth brake R / B. Absent. That is, the friction mating plate 61 may not be able to be splined with the automatic transmission case ATC all around the circumference. In this case, the friction mating plate 61 cannot be held when the fifth brake R / B is engaged. There is a possibility that a large torque cannot be transmitted.
(2) Even if the necessary torque can be transmitted only with a spline that can be provided on the automatic transmission case ATC side, if the friction counterpart plate 61 is to be spline fitted to the automatic transmission case ATC. The outer diameter of the fifth brake R / B becomes unnecessarily large. Therefore, the members such as the first drum member 41 are also increased, increasing the weight and increasing the cost.

Here, the torque sharing ratio of the fifth brake R / B will be described.
The torque sharing ratio of each frictional engagement element in each shift stage in the skeleton of the first embodiment is as shown in the table of FIG. In FIG. 12,
αf is the tooth number ratio (αf = Zss / Zr) on the front side (single pinion side).
However, Zss: the number of teeth of the front sun gear Ss, Zr: the number of teeth αr of the ring gear R is the rear side (double pinion side) tooth number ratio (αr = Zsd / Zr).
However, since Zsd is the number of teeth of the rear sun gear Sd, Zr is the number of teeth of the ring gear R and the number of teeth of the sun gear <the number of teeth of the ring gear. The maximum torque sharing ratio is as follows.
Maximum torque sharing ratio of 5th brake R / B: (1 + αf) / αf
Maximum torque sharing ratio of second clutch 234 / C: αf + 1
Maximum torque sharing ratio of the first clutch 13R / C: 1
Maximum torque sharing ratio of 3rd brake 12 / B: (αr (1 + αf)) / (αf (1-αr))
Maximum torque sharing ratio of 4th brake 4 / B: αf / (1 + αf)
As is clear from the above torque sharing ratio, the maximum torque sharing ratio of the fifth brake R / B> the maximum torque sharing ratio of the second clutch 234 / C for the three frictional engagement elements arranged on the front side of the output gear OUT. > The maximum torque sharing ratio of the first clutch 13R / C is established.
As described above, the maximum torque sharing ratio of the fifth brake R / B is larger than the maximum torque sharing ratio of the second clutch 234 / C and the first clutch 13R / C. If the friction partner plate 61 is not sufficiently held, a large torque cannot be transmitted.

[Drum holding action of fifth brake]
As described above, in the fifth brake R / B receiving high torque, when the fifth brake drum 42 is used to hold the friction counterpart plate 61, the case fixability of the fifth brake drum 42 is ensured. There is a need. Hereinafter, the drum holding action of the fifth brake R / B will be described with reference to FIG.

  First, in the first embodiment, the fifth brake drum 42 that is a case side member to which the common carrier C is locked is spline-fitted so as not to be relatively rotatable with respect to the spline 21c provided on the intermediate wall 21 that is a case fixing member. Let For this reason, fastening parts such as bolts for fixing the fifth brake drum 42 are not required.

  However, the spline fitting between the fifth brake drum 42 and the intermediate wall 21 cannot be removed simply by fitting the fifth brake drum 42 with the spline 21c provided on the intermediate wall 21 so that the fifth brake drum 42 cannot rotate relative to the spline 21c. It can happen. When such a spline fitting failure occurs, dragging occurs between the friction plate 60 and the friction counterpart plate 61 even when the fifth brake piston 43 is not pressed.

  On the other hand, in the first embodiment, the fifth brake return spring 45 is arranged between the fifth brake drum 42 and the fifth brake piston 43. Then, as shown in FIG. 6, the urging force of the fifth brake return spring 45 is adjusted so that the fifth brake piston 42 is pushed back to the one side (arrow E direction side) that presses the fifth brake drum 42 against the intermediate wall 21. The structure which acts on both the other side (arrow F direction side) which returns to a position is employ | adopted.

  That is, the fifth brake return spring 45 that returns the fifth brake piston 43 to the position where the pressing of the friction plate 60 and the friction counterpart plate 61 is released is removed from the fifth brake drum 42 that is spline-fitted to the intermediate wall 21. It also serves as a prevention member to prevent it from coming off. For this reason, an additional part for preventing the fifth brake drum 42 that is spline-fitted to the intermediate wall 21 from being detached is unnecessary.

  Thus, (a) no fastening parts such as bolts are required. (b) Since the acting force for preventing the fifth brake drum 42 from coming off is obtained by the existing fifth brake return spring 45, an additional part for preventing the coming off is unnecessary. For these two reasons (a) and (b), the case fixing of the fifth brake drum 4 for spline-fitting the friction counter plate 61 is ensured while suppressing an increase in the number of parts.

  As shown in FIG. 6, the fifth brake drum 42 is provided by being splined to the intermediate wall 21, and the rear drum bottom 42 a is in contact with the drum contact surface 21 d of the intermediate wall 21. The fifth brake drum 42 is provided with a snap ring 70 on the front side of the friction plate 60 and the friction counterpart plate 61. The snap ring 70 receives a reaction force of the return spring 45 for returning the fifth brake piston 43.

  Therefore, when the fifth brake R / B is engaged, the friction plate 60 and the friction counterpart plate 61 are pressed from the fifth brake piston 43, whereby power is transmitted between the friction plate 60 and the friction counterpart plate 61. When the hydraulic pressure acts on the fifth brake piston 43 and the fifth brake piston 43 moves in the direction of the arrow E in FIG. 6, the fifth brake drum 42 is connected to the fifth brake drum 42 via the return spring 45 and the snap ring 70. A biasing force in the direction of arrow E in FIG. By this urging force, the drum bottom portion 42a of the fifth brake drum 42 is pressed against the drum contact surface 21d of the intermediate wall 21, and the fifth brake drum 42 is reliably prevented from coming off.

Next, the effect will be described.
In the brake mechanism of the first embodiment, the effects listed below can be obtained.

(1) A brake mechanism (fifth brake R / B) capable of locking the rotating element (common carrier C),
A first connecting member (first drum member 41) connected to the rotating element (common carrier C) and in which the friction plate 60 is spline-fitted so as not to be relatively rotatable;
A second connecting member (fifth connecting member) that is spline-fitted to the case (automatic transmission case ATC) that accommodates the rotating element (common carrier C) so as not to be relatively rotatable, and the friction counterpart plate 61 is spline-fitted not to be relatively rotatable. Brake drum 42);
A stopper member (intermediate wall 21) for restricting movement of the second connecting member (fifth brake drum 42) to one side;
A piston member (fifth brake piston 43) provided to be able to press the friction counterpart plate 61 toward the one side;
It arrange | positions between the said 2nd connection member (5th brake drum 42) and a piston member (5th brake piston 43), and is said one side with respect to the said 2nd connection member (5th brake drum 42). An elastic member (fifth brake return spring 45) that generates a biasing force to the other side that is the opposite direction of the one side with respect to the piston member (fifth brake piston 43);
Is provided.
For this reason, it is possible to ensure case fixing of the second connecting member (fifth brake drum 42) to which the friction counter plate 61 is spline-fitted while suppressing an increase in the number of parts.

(2) The brake mechanism (fifth brake R / B) is a brake mechanism capable of locking the rotating element (common carrier C) of the automatic transmission,
A wall portion 21a that is connected to the case (automatic transmission case ATC) and extends in the radial direction, and a cylindrical portion 21b that extends from the wall portion 21a to the one side in the axial direction. An intermediate wall 21 that supports (output gear OUT),
The stopper member is constituted by the intermediate wall 21, and the second connecting member is formed by bringing the end of the one side of the second connecting member (fifth brake drum 42) into contact with the intermediate wall 21. The movement of the (fifth brake drum 42) to one side is restricted.
For this reason, in addition to the effect (1), the end of the second connecting member (fifth brake drum 42) is pressed against the intermediate wall 21 by the biasing force of the elastic member (fifth brake return spring 45). Further, it is possible to reliably prevent the second connecting member (the fifth brake drum 42) from coming off.

  As described above, the brake mechanism of the present invention has been described based on the first embodiment. However, the specific configuration is not limited to the first embodiment, and the gist of the invention according to each claim of the claims is described. Unless it deviates, design changes and additions are allowed.

  In Example 1, the example which has arrange | positioned the 1st drum member 44 (1st connection member) to the inner peripheral side of the drum 42 for 2nd brakes (2nd connection member) was shown. However, a second connecting member may be provided on the inner peripheral side of the first connecting member, and the rotating element connected to the first connecting member may be locked.

  In the first embodiment, the fifth brake drum 42 (second connecting member) is brought into contact with the intermediate wall 21 to restrict the movement of the fifth brake drum 42 (second connecting member) to one side. showed that. However, a snap ring may be fitted into a spline of a case side member such as an intermediate wall, and the movement of the second connecting member to one side may be restricted by this snap ring.

  In the first embodiment, the brake mechanism of the fifth brake R / B, which is one of friction engagement elements of the automatic transmission, is shown. However, other than the brake mechanism applied to the automatic transmission, any brake mechanism that locks the rotating element by pressing and fastening the friction plate / friction counterpart plate with the piston can be applied.

  In Example 1, the 5th brake drum 42 which formed the spline over the perimeter was shown. However, it is only necessary to sufficiently secure the friction mating plate when the fifth brake R / B is engaged, without forming splines around the entire circumference.

PGU Rabinio planetary gear
Ss front sun gear
Sd Rear sun gear R Ring gear
P _L Long pinion
P _S Short pinion C Common carrier (rotating element)
IN input shaft
OUT Output gear (output member)
ATC automatic transmission case (case)
13R / C 1st clutch
234 / C Second clutch
12 / B 3rd brake
4 / B 4th brake
R / B 5th brake (brake mechanism)
21 Intermediate wall (stopper member)
21a Wall portion 21b Cylindrical portion 21c Spline 21d Drum contact surface 27 Front carrier plate 40 Cylindrical connecting plate 41 First drum member (first connecting member)
42 Fifth brake drum (second connecting member)
42a Drum bottom 43 fifth brake piston (piston member)
44 Bulkhead 45 Fifth brake return spring (elastic member)
60 Friction plate 61 of fifth brake R / B 61 Friction counterpart plate 70 of fifth brake R / B Snap ring 71 Spring support plate

Claims (2)

A brake mechanism capable of locking the rotating element,
A first connecting member connected to the rotating element, the friction plate being spline-fitted so as not to be relatively rotatable,
A second connecting member that is spline-fitted to the case containing the rotating element so as not to be relatively rotatable, and the friction partner plate is spline-fitted to be relatively non-rotatable;
A stopper member for restricting movement of the second connecting member to one side;
A piston member provided to be able to press the friction counterpart plate toward the one side;
It is disposed between the piston member and the second connecting member, the one to generate a biasing force to the side relative to the second coupling member, which is opposite direction of the one side relative to the piston member the other An elastic member that generates a biasing force to the side ,
Brake having a configuration in which the urging force of the elastic member is applied to both one side pressing the second connecting member against the stopper member and the other side returning the piston member to the original position. mechanism. The brake mechanism according to claim 1, wherein
The brake mechanism is a brake mechanism capable of locking a rotating element of an automatic transmission,
A wall portion connected to the case and extending in the radial direction; and a cylindrical portion extending from the wall portion to the one side in the axial direction, the intermediate wall supporting the output member at the cylindrical portion,
The stopper member includes the intermediate wall, and restricts the movement of the second connecting member to one side by bringing the end of the one side of the second connecting member into contact with the intermediate wall. Brake mechanism characterized by