JP2832439B2 - Ring gear structure of planetary gear of automatic transmission - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a structure of a ring gear of an automatic transmission provided with a starting device and a planetary gear device.

(Prior art)

An automatic transmission in which a main transmission having a starting device and a planetary gear device and a subtransmission having a planetary gear device are arranged in series,
For example, it is disclosed in Japanese Patent Application Publication No. 502274 in 1986.

FIG. 1 of the above publication discloses an automatic transmission in which a ring gear of a main transmission and a ring gear of an auxiliary transmission are connected, but FIG. 1 only shows a gear train of the automatic transmission. The specific configuration of the member that connects the ring gear is not shown. In FIG. 1, a one-way clutch is interposed between the main transmission and the sub-transmission, so that the ring gear of the main transmission and the ring gear of the sub-transmission are connected via a shaft member. ing.

[Problems to be solved by the invention]

An automatic transmission that connects a main transmission and an auxiliary transmission in series
While it is easy to achieve multiple speeds, the axial dimension tends to be large. When the ring gear is used as the output member of the main transmission, the peripheral speed of the ring gear increases, so that the ring gear is likely to be a source of noise.

The present invention shortens the axial dimension by directly connecting a ring gear as an output member of a main transmission and a ring gear as an input member of a subtransmission via a drum, thereby reducing the rotational axis of the drum to the tooth surface of the ring gear. An object of the present invention is to provide a ring gear structure that reduces noise by performing centering.

[Means for solving the problem]

The present invention includes a drum (95) integrally connecting a ring gear (96) of a main transmission and a ring gear (101) of a subtransmission, and a wall (951) formed inside the drum (95) and extending in an axial direction. The hole (952) provided in the inner peripheral portion of the drum (952) has a gap between the shaft member and the thrust bearing (951a) inserted on both sides of the wall to regulate the axial position of the drum. The rotation axis of the ring gear (96,10
1) Alignment is achieved by aligning the tooth surface with the tooth surface of the pinion (84, 102) that meshes with the ring gear.

Note that some of the reference numerals in parentheses described above are in contrast to the drawings, but do not limit the configuration in any way.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 shows a skeleton of the automatic transmission. The automatic transmission 1 includes a torque converter 2 as a starting device and a transmission 3. The transmission 3 comprises a main transmission 4 and an auxiliary transmission 10 arranged concentrically. The main transmission 4 achieves four forward speeds and one reverse speed, and the auxiliary transmission 10 is directly connected with a reduction ratio of 1. And a reduction ratio of 1 or more. The transmission 3 has five clutches and three brakes as friction engagement elements.
And three one-way clutches.

The torque converter 2 includes a converter case 21 which is an input member connected to a crankshaft of the engine. The converter case 21 drives a pump impeller 22. The hydraulic oil pressurized by the pump impeller 22 passes through a one-way clutch 24, passes through a stator 23 supported by a case 30 of the transmission 3, drives a turbine runner 27, and outputs power to a turbine output shaft.
Communicate to 28. A lockup clutch 26 for connection is provided between the pump impeller 22 and the turbine output shaft 28, and the converter case 21 and the output shaft 28 are directly connected when necessary.

The output shaft 28 of the torque converter 2 acts as the input shaft of the main transmission 4 and this input is transmitted to the clutch drum 40 of the first clutch 41. The first clutch 41 is a forward clutch which is always activated when the vehicle is moving forward.
The power is supplied to the first one-way clutch 45 via the clutch hub 43.
Transmitted to the outer race 46 integrated with the clutch hub 43 of the
An inner race 47 of the first one-way clutch 45 drives a large sun gear shaft 48 and a large sun gear 49 integrated with the large sun gear shaft 48. The first one-way clutch 45 operates during the first to fourth speeds. A second clutch 52 is arranged inside the drum 40 of the first clutch 41. The second clutch 52 is a clutch that operates at the 4th speed and the 5th speed, but the clutch hub 53 is an intermediate shaft.
The intermediate shaft 55 is connected to the carrier 54 of the planetary gear set 80.
I support.

The drum 40 of the first clutch 41 is connected to the drum 60 of the fifth clutch 65. The fifth clutch 65 is a so-called coast clutch that transmits torque from the wheel side to the engine side, and its hub 67 is connected to the large sun gear shaft 48. The fifth clutch drum 60 is connected to the hub 74 of the third clutch 73. The third clutch 73 is a so-called reverse clutch that operates when the vehicle is traveling in reverse. The clutch drum 75 is connected to a small sun gear 78 via a small sun gear shaft 77. The drum 75 of the third clutch 73 is connected to the first brake 71
The first brake 71 is 3
Activated at the 5th and 5th speeds.

The planetary gear device 80 is a so-called Ravigneaux type planetary gear device having two sun gears having different numbers of teeth and sharing a carrier and a ring gear. In the present invention, a Ravigneaux II type gear train having a ring gear as an output is used. adopt.

One end of the shaft 81 and the shaft 83 is attached to the carrier 54 integrally connected to the intermediate shaft 55. The shaft 81 supports a long pinion 82, and the shaft 83 supports a short pinion 84. The large sun gear 49 meshes with the long pinion 82 and the small sun gear 78 meshes with the short pinion 84, respectively.

The other ends of the shafts 81 and 83 are connected to a hub 85 of a third brake 93. The hub 85 supports a brake disk of a friction plate type brake 93 at an outer peripheral portion thereof.
Supported on the 30 side. The third brake 93 is in reverse and 1st gear,
Operates for second-speed engine braking and the like.

An inner peripheral portion of the hub 85 forms an outer race 91 of the second one-way clutch 90, and an inner race 92 of the one-way clutch 90 is integrally fixed to the support 35 fixed to the case 30.
The second one-way clutch 90 operates in first and second gear.

The short pinion 84 meshes with a ring gear 96 formed inside one end of a drum 95, and the drum 95 functions as an output member of the main transmission 4 and as an input member of the subtransmission 10.

That is, a ring gear 101 is integrally formed inside the other end of the drum 95, and a pinion 102 supported by a shaft 105 meshes with the ring gear 101. One end of shaft 105 is carrier 10
3, and the carrier 103 is integrated with the output shaft 120. The other end of the shaft 105 is connected to the clutch hub of the fourth clutch 104, and the clutch drum 110 of the fourth clutch 104 also serves as the brake drum of the second brake 112.

The fourth clutch 104 operates at the second to fifth speeds, and brings the auxiliary transmission 10 into a directly connected state. The second brake 112 is a reverse brake that operates when the vehicle is moving in reverse and the first speed engine brake, and employs a band-type brake.

The other end of the shaft 108 formed at one end with a sun gear 106 meshing with the pinion 102 forms an inner race 109 of a third one-way clutch 113, and an outer race 115 of the one-way clutch 113.
Is fixed to the case 30. The drum 110 is integrally connected to the shaft 108.

FIG. 1 shows a cross section of the automatic transmission. The automatic transmission generally designated by reference numeral 1 comprises a torque converter 2 and a transmission 3. The torque converter 2 is provided in a case 20 and includes a drum-shaped converter case 21 connected to a crankshaft of the engine at the forefront (hereinafter, the side closer to the engine is referred to as “front side”). Converter case 21 connects and drives the engine crankshaft and pump impeller 22, and the hydraulic oil pressurized by pump impeller 22 drives turbine runner 27 and returns to pump impeller 22 through stator 23. . The turbine runner 27 drives a turbine shaft 28 directly connected thereto.

The stator 23 is supported by a fixed portion 30 via a one-way clutch 24, and a lock-up piston 25 is disposed between the turbine runner 27 and the drum-shaped converter case 21, and when necessary, the lock-up piston 25 and the converter case 21 are connected. The lockup clutch 26 is operated to directly connect the converter case 21 with the turbine output shaft 28 and the input shaft 28 of the transmission. Torque converter 2 case 20
And an oil pump cover 31, a partition plate 32, and an oil pump housing
Place 33.

The oil pump cover 31 includes a face-plate-shaped portion provided inside an oil passage or the like and a boss portion having a central portion protruding rearward. Divider
An oil pump 32 supports the side surface of the rotating body of the oil pump 29 and defines an oil passage and the like. The oil pump 29 is formed in an oil pump housing 33.

The rear end of the pump impeller 22 is connected to the rotating body of the oil pump 29. The rotating body of the oil pump 29 is an oil pump
Driven in 29 to generate the required hydraulic pressure. The oil pump cover 31 includes an oil passage for the oil pump 29 formed therein, and a face plate 311 that covers an opening on the front surface of the transmission case.
A hollow boss 312 projecting from the center of the transmission case to the inside of the case, and a hollow tubular support cylinder 34 is press-fitted into the hollow boss 312.

The support cylinder 34 is a shaft connected to the turbine runner 27 of the torque converter through sleeves and bearings inside the front and rear ends.
Support 28. This shaft 28 is the input shaft of the transmission 3,
The rear end of the shaft 28 has a radially expanding flange portion 281. Thrust bearings of the same diameter are interposed on both sides of the flange portion 281.

An outer peripheral portion of the flange 281 is connected to an inner cylinder 401 of the clutch drum 40, and a first clutch 41 is provided inside the clutch drum 40. The clutch drum 40 has a cylindrical shape whose front end is supported and whose rear end is open.
And rotate together. The inner diameter side of the inner cylinder 401 slides and rotates with respect to the outer peripheral surface of a cylindrical oil passage member 315 having an oil passage fitted on the outer peripheral portion of the boss 312 of the front support 31.

A large-diameter piston 42 and a small-diameter piston 56 are inserted into the outer peripheral portion of the inner cylinder 401 in the form of a double piston. The large-diameter piston 42 also serves as a cylinder of the small-diameter piston 56, and is fitted inside the drum 40 in a liquid-tight manner. Large diameter piston
Reference numeral 42 is for operating the first clutch 41. When the piston 42 is operated, the clutch 42 is splined inside the drum 40 and the clutch disk splined to the clutch hub 43. To transmit power. A wall surface 43 extending in the axial direction is provided on the front side of the clutch hub 43.
1 are formed, and the slide bearings are arranged on both sides of the wall surface 431. The inner diameter of the clutch hub 43 forms an outer race 46 of the first one-way clutch 45, and the one-way clutch 45
The inner race 47 is formed integrally with the front end of the large sun gear shaft 48. A large sun gear 49 is attached to the rear end of the large sun gear shaft 48 via a serration. The large sun gear shaft has a cylindrical shape, and the inner peripheral portions at the front and rear ends thereof are supported by the intermediate shaft 55 by bearings.

A second clutch 52 is provided on the radially inner side of the large-diameter piston 42.
Then, a small-diameter clutch piston 56 for operating the clutch 52 is provided. The clutch plate is spline-engaged with the inner peripheral surface of the piston 42, and the clutch disk is spline-engaged with a clutch hub 53 disposed inside. The small-diameter piston 56 transmits power between the large-diameter piston 42 and the hub 53 that rotate integrally with the drum 40. The large-diameter piston 42 and the small-diameter piston 56 are constantly urged in a non-operating direction by a return spring 541 stretched between the piston 42 and the inner cylinder 401.

The clutch hub 53 is a wall surface 53 extending from the rear end side to the shaft center.
The spline serration is connected to the vicinity of the front end of the intermediate shaft 55 via the first shaft 55. The front end of the intermediate shaft 55 is supported by a rear end inner diameter portion of the input shaft 28 via a bearing. The rear end of the intermediate shaft 55 is supported by the front end of the output shaft described later.
In the vicinity of the rear end, a carrier 54 that expands in the radial direction is provided.

The open rear end of the drum 40 containing the first clutch 41 and the second clutch 52 is connected to the clutch drum 60 of the fifth clutch by a spline. Inside the clutch drum 60, there is provided a fifth clutch 65 composed of a clutch plate spline-engaged inside the clutch drum 60 and a clutch disk spline-engaged with a clutch hub 67 located inside the clutch drum 60. . Wall surface 671 formed from the front side of clutch hub 67 toward the axis
Is coupled to a large sun gear shaft 48. Clutch drum
An inner cylinder 601 is formed on the inner peripheral side of 60, and an outer peripheral side of the inner cylinder 61 slidably supports the piston 66. A return spring 661 is provided between the piston 66 and the inner cylinder 601. The inner peripheral side of the inner cylinder 601 is rotatably supported by a stepped cylindrical member 771. On the opposite side of the clutch drum 60 from the fifth clutch 65, there is a clutch hub.
74 is integrally fixed to the drum 60, and the clutch hap 74 is the third
The clutch disk constituting the clutch 73 is supported via splines. The clutch plate of the third clutch 73 is supported by a drum 75 also serving as an outer cylinder. A belt-type first brake 71 is provided on the outer periphery of the drum 75. An inner cylinder 751 is formed on the inner peripheral side of the drum 75,
A piston 76 for operating the clutch 73 is slidably supported on the outer peripheral side of the inner cylinder 751. A return spring 761 is provided between the inner cylinder 751 and the piston 76.
The tip of the inner cylinder 751 is spline-engaged with the cylindrical member 771, and the inner peripheral portion of the cylindrical member 771 is connected to the front end of the small sun gear shaft 77, so that the drum 75 rotates integrally with the small sun gear shaft 77. The small sun gear shaft 77 has a cylindrical shape, and a small sun gear 78 is formed at the rear end thereof. The inner peripheral portions of the front and rear ends of the small sun gear shaft 77 are supported by the large sun gear shaft 48 via bearings.

A central support member 35 is provided at a central portion inside the case 30. The central support member 35 has a flange portion engaging with the inner peripheral portion of the case, a stepped boss formed in the inner diameter direction of the flange portion and projecting forward and a short boss projecting rearward and projecting forward. A small diameter ring member 36 is provided on the outer periphery of the boss step.
And a large-diameter ring member 37 are fitted respectively. The small-diameter ring member 36 rotates and slides on the outer peripheral portion with the inner peripheral portion of the cylindrical member 771, and the large-diameter ring member 37 rotates on the drum 75 at the outer peripheral portion.
The inner cylinder 751 is rotatably supported by the ring member 37 via a bearing and a bearing.

The intermediate shaft 55 supports the large sun gear shaft 48, and the large sun gear shaft 48
Supports the small sun gear shaft 77, the shaft portion has a triple shaft structure.

The rear side of the flange portion of the central support member 35 forms a cylinder into which a piston 94 for operating a third brake 93 is fitted. An iron sleeve 38 is press-fitted into the inner diameter portion of the central support member 35, and the rear end of the sleeve 38 is formed in a ring shape, and the inner race of the second one-way clutch 90 is formed.
Press 92. A return spring 941 is interposed between the inner race 92 and the piston 94. An outer race 91 of the second one-way clutch 90 doubles as a hub of the third brake 93, and a brake disk is spline-engaged with an outer peripheral portion thereof. The brake plate of the third brake 83 is fitted on the inner periphery of the case 30 with splines.

A ring member 911 is fixed to the rear side of the outer race 91 of the second one-way clutch 90, and a pinion shaft 81 and a pinion shaft 83 are supported between the ring member 911 and the carrier 54 of the intermediate shaft 55. A plurality of these pinion shafts 81 and 83 are provided, respectively. The pinion shaft 81 supports a long pinion 82, and the pinion shaft 83 supports a short pinion 84. The short pinion 84 meshes with the small sun gear 78 and the ring gear 96, and the long pinion 82 meshes with the first sun gear 49.

The ring gear 96 is fixed to the front end of the drum 95. An inner hole formed in the wall surface 951 of the drum 95 has a gap between the ring gear 96 and an intermediate shaft, and both side surfaces are supported by slide bearings.
The ring gear 96 has a ring gear 101 at the rear end opposite to the wall 951.

The ring gear 101 provides an input to the sub-transmission. The sub-transmission is a speed reducer having a set of planetary gears as described above, and is of a type that takes out the input of the ring gear from the carrier and outputs it. . The pinion 102 meshing with the ring gear 101 meshes with the sun gear 106, and the pinion 102
Is supported by a shaft 105. The shaft 105 has a front end supported by a carrier 103 formed at the front end of the output shaft 120, and a rear end of the shaft 105 provided with a hub 107 of a fourth clutch 104. Clutch hub 10
7 spline-supports the clutch disk, and spline-supports the clutch plate on the inner peripheral portion of the opposing drum 112.

A second brake 112 is arranged on the outer periphery of the drum 110.

A stepped cylindrical rear shaft support member 125 protruding toward the front of the case 30 is attached to the rear wall of the transmission case 30. A cylindrical sun gear shaft 108 is formed around the outer periphery of the rear shaft support member 125.
To support the inner peripheral part. The sun gear shaft 108 has at its front end a sun gear 106 that meshes with the pinion 105, and the rear portion of the sun gear shaft 108 is integrated with the drum 110. A piston 116 is fitted inside the drum 110, and a return spring 117 is provided between the piston 116 and the sun gear shaft 108.

On the rear side of the drum 110 of the sun gear shaft 108, an inner race 109 of a third one-way clutch 113 is formed, and a one-way clutch is formed.
The 113 outer races 115 are spline-supported inside the case 30.

At the rear end of the case 30, a rear case 301 that supports the output shaft 120
The output shaft is supported by bearings arranged inside the front end of the rear shaft support member 125 and inside the rear end of the rear case 301, and the rear end outside diameter of the intermediate shaft 55 is supported by the front inside diameter of the output shaft.

The output shaft 120 is provided with a parking gear 126 and a drive gear 131 of a speedometer. The parking gear 126 achieves a parking brake in cooperation with the pawl 127 disposed on the fixed side, and the drive gear 131 drives a speedometer.

The parking gear 126 is integrally provided with a flange 129, and the number of rotations of the output shaft 120 is obtained by detecting the passage of the flange slit by the sensor 130.

A connecting member 135 for connecting to the axle shaft is inserted into the rear end of the output shaft 120, and is fixed to the output shaft 120 with a nut 136. A hydraulic control device (not shown) is provided below the transmission case 30 to control the operation of clutches and brakes of the transmission. The hydraulic control device is covered with a cover 11 also serving as an oil pan.

 Hereinafter, the operation of the automatic transmission will be described.

The present automatic transmission performs automatic shifts of five forward speeds and one reverse speed. Table 1 shows each shift speed and the operation of a friction engagement element that achieves the shift speed.

Table 1 shows the shift speed in the vertical column and the frictional engagement element in the horizontal column. The mark ○ indicates that the frictional engagement element is operating, and the mark (○) indicates that it operates when the engine is braked. Is shown. Reference numerals 41, 52, 73, 104 and 65 indicate the first to fifth clutches, respectively, and reference numerals 71, 112 and 93 respectively indicate the first clutch.
Brake to third brake are shown, and reference numerals 45, 90 and 113 indicate first to third one-way clutches, respectively.

3 to 8 show transmission paths of power at each shift speed, where a bold line indicates a path through which power is transmitted, and a hatched part indicates a fixed element.

FIG. 3 shows a power transmission path at the first speed.
The power from the first clutch 41 to the first one-way clutch 45
To drive the large sun gear shaft 48 and the large sun gear 49.
Since the shaft 81 of the long pinion with which the large sun gear 49 meshes is fixed by the action of the second one-way clutch 90, the rotation of the large sun gear 49 is reduced and transmitted to the ring gear 96.
This rotation is transmitted to the ring gear 101 via the drum 95. At the first speed, the sun gear shaft 108 of the planetary device constituting the auxiliary reduction gear is fixed by the action of the third one-way clutch 113, so that the rotation input from the ring gear 101 is reduced and transmitted to the carrier 103 to be transmitted to the output shaft 120. Output from

That is, in the first speed, the rotation reduced by the main transmission is further reduced by the auxiliary transmission and output.

FIG. 4 shows the power transmission path at the second speed, and the same path as the first speed is used up to the drum 95 which also serves as the output shaft of the main transmission and the input shaft of the auxiliary transmission.

The fourth clutch 104 of the sub-transmission operates to hold the sub-transmission in a directly connected state, and the input shaft from the drum 95 remains unchanged as the output shaft.
It is transmitted to 120.

FIG. 5 shows a power transmission path at the third speed, in which the first brake 71 operates to fix the small sun gear shaft 77. The power of the large sun gear shaft 48 is reduced from the large sun gear shaft 49 and transmitted to the ring gear. The reduction ratio at this time is determined by the number of teeth of the small sun gear 78, the large sun gear 49, and the ring gear 96. The fourth clutch 104 operates to maintain the direct connection state of the auxiliary transmission, and the power of the drum 95 is transmitted to the output shaft as it is.

FIG. 6 shows a power transmission path at the time of the fourth speed, in which both the first clutch 41 and the second clutch 52 operate. Therefore, the power of the input shaft 28 is transmitted to both the intermediate shaft 55 and the large sun gear shaft 48, and the planetary gear train does not move relative to each other.
55, the large sun gear shaft 48 is directly connected to the drum 95. The sub-transmission also keeps the direct connection state, and the input shaft 28 and the output shaft 120 are directly connected after all.

FIG. 7 shows a power transmission path at the 5th speed. The second clutch 52 operates to transmit the power of the input shaft 28 to the intermediate shaft 55. Since the first brake 71 operates to fix the small sun gear shaft 77, the rotation of the carrier 54 integrated with the intermediate shaft 55 is increased in speed and transmitted to the drum 95. Since the direct connection state of the auxiliary transmission is maintained, the power of the drum 95 is transmitted to the output shaft 120 as it is.

The fifth speed is an overdrive in which the rotation speed of the input shaft 28 is increased and transmitted to the output shaft 120.

FIG. 8 shows a power transmission path when the vehicle is moving backward. The third clutch 73 operates to transmit the power of the input shaft 28 to the small sun gear shaft 77. Since the third brake 93 is operated to fix the short pinion shaft 83 meshing with the small sun gear shaft 78, the rotation of the small sun gear shaft 78 is reversed with deceleration and transmitted to the ring gear 96 and the drum 95. Since the second brake 112 of the auxiliary transmission also operates to fix the sun gear shaft 108, the power input to the ring gear 101 is reduced and transmitted from the carrier 103 to the output shaft 120. Therefore, at the time of reversing, the speed is further reduced by the auxiliary transmission.

This speed change state is shown in the speed diagram of FIG. In the figure, reference numeral 4 indicates a main transmission provided with a Ravigneaux planetary gear mechanism, and reference numeral 10 indicates a subtransmission which achieves reduction (under drive).

The transmission ratio of each transmission is determined by appropriately selecting the number of gear teeth of the planetary gear train. In this transmission, the auxiliary transmission acting as a speed reducer is operated only at the first speed and the reverse speed. The reason is to avoid as much as possible the control for engaging and disengaging two clutches and brakes at the same time.

FIG. 10 shows the details of the ring gear structure of the planetary gear according to the present invention. For the sake of explanation, only the portion above the center line of the automatic transmission shown in FIG. 1 is shown.

As described in FIGS. 1 and 2, the Ravigneaux type planetary gear set of the main transmission 4 has a long shaft rotatably supported by a shaft 81 attached to a carrier 55 provided at the rear end of the intermediate shaft 55. It has a pinion 82 and a short pinion (not shown) rotatably supported on a shaft (not shown) also mounted on the carrier 55.

The long pinion 82 meshes with a large sun gear 49 which is integrally attached to the rear end of the large sun gear shaft 48 supported by the bearing 556 on the intermediate shaft 55 by serration, and the short pinion is supported by a bearing 484 on the large sun gear shaft 48. It meshes with a small sun gear 78 formed integrally with the rear end of the sun gear shaft 77.

The short pinion simultaneously meshes with the ring gear 96, and the output of the main transmission 4 is taken out of the ring gear 96. The ring gear 96 is attached to the tip of the drum 95, and has an inner hole 952 in the inner peripheral portion of the wall surface 951 of the drum 95.

Drum 95 on the opposite side of ring gear 96 across wall 951
At the rear end, another ring gear 101 is integrally fixed to the drum.

The ring gear 101 serves as an input member of the auxiliary transmission 10 including a one-stage planetary gear device.
It meshes with the pinion 102 that is rotatably supported at 05. The shaft 105 is attached to a carrier 103 formed at the tip of an output shaft 120, and the pinion 102 meshes with a sun gear 106 formed at the tip of a sun gear shaft 108 at the inner periphery.

The front end of the sun gear shaft 108 is supported on the outer periphery of the rear support member 125 via a bearing 125h, and the inner periphery of the rear support member 125 supports the outer periphery of the main power shaft 120 via a bearing 120a. The inner peripheral portion of the front end of the output shaft 120 is supported by a bearing 554 at the rear end of the intermediate shaft 55.

An inner hole 952 formed in the wall surface 951 of the drum 95 has a gap with respect to the outer peripheral portion of the intermediate shaft 55 and the output shaft 120. Thrust bearings 951a, 951a are inserted between the carrier 54 and the carrier 103 of the output shaft 120 to regulate the axial position of the drum 95. A plurality of projections 954 project on the circumference of a wall surface 951 corresponding to the outer peripheral portion of the thrust bearing 941a to support the thrust bearing. The projections 954 are alternately projected on both sides of the wall surface 951 to support the thrust bearings on both sides.

Since the peripheral speed of the drum 95 is the highest in this transmission, noise is likely to be generated on the meshing surface between the ring gear 96 and the ring gear 101. For the drum of the present invention, the wall 951
Since the inner hole 952 of the drum 95 is a free end in the radial direction, the axis of the drum 95 is
Self-centering by the mating surface of Therefore, the ring gear 96 and the short pinion and the ring gear 10
The meshing state between the pinion 1 and the pinion 102 meshing with the pinion 1 is maintained in the best condition, and the generation of noise can be minimized.

In the present transmission, at the fifth speed when the peripheral speed of the drum 95 is the highest, the sub-transmission 10 is in a directly connected state, and the ring gear 101 and the pinion 102 do not relatively move. This state is the same as when the ring gear 101 and the pinion 102 are in spline engagement. Therefore, in this state, by adjusting the meshing between the ring gear 96 and the meshing surface of the short pinion meshing with the ring gear 96, the meshing state can be maintained at the best and noise generation can be reduced.

〔The invention's effect〕

As described above, the present invention provides an automatic transmission having a configuration in which a main transmission equipped with a planetary gear unit and a subtransmission equipped with a planetary gear unit for reduction are connected in series to output a ring gear of the main transmission. The input member of the auxiliary transmission is also a ring gear, and a drum having ring gears formed at both ends is a member connecting the main and auxiliary transmissions. With this configuration, the main and auxiliary transmissions can be rationally connected, and the axial length can be reduced.

In addition, since the drum is a member having a high peripheral speed, it is necessary to attach the concentricity with other rotating members with a high degree. However, in the present invention, the drum is centered around the meshing surface between the ring gear and the pinion. With the configuration, the accuracy of the meshing surface is improved, and generation of noise can be prevented.

[Brief description of the drawings]

 FIG. 1 is a cross-sectional view of the automatic transmission of the present invention, FIG. 2 is an explanatory view showing an outline of the automatic transmission, FIG. 3 is an explanatory view showing a power transmission system at the first speed, and FIG. Explanatory diagram showing the power transmission system at the second speed, FIG. 5 is an explanatory diagram showing the power transmission system at the third speed, FIG. 6 is an explanatory diagram showing the power transmission system at the fourth speed, FIG. 7 is an explanatory diagram showing a power transmission system at the fifth speed, FIG. 8 is an explanatory diagram showing a power transmission system at the time of reverse travel, FIG. 9 is a diagram showing a speed ratio, and FIG. It is sectional drawing of a principal part. 1 ... automatic transmission, 2 ... torque converter, 4 ... main transmission, 10 ... auxiliary transmission, 28 ... input shaft, 30 ... transmission case, 35 ... central support member, 48 ... Large sun gear shaft, 55 …… Medium shaft, 77 …… Small sun gear shaft, 95 …… Drum, 96 …… Ring gear, 101 …… Ring gear, 103 …… Carrier, 106 …… Sun gear, 108 …… Sun gear shaft, 120… ... Output shaft.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-34027 (JP, A) JP-T-61-502274 (JP, A) Fully open 1988-86456 (JP, U) Really open 1983 91042 (JP, U) Actually open 1987-200031 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16H 57/08 F16H 3/44-3/78

Claims (1)

(57) [Claims] 1. A starter, a main transmission having a planetary gear set whose ring gear is an output member, and a subtransmission having a reduction planetary gear set whose ring gear is an input member are arranged in series. In a ring gear structure of a planetary gear of an automatic transmission, a drum is provided for integrally connecting a ring gear of a main transmission and a ring gear of a subtransmission, and the drum is provided on an inner peripheral portion of an axially extending wall formed inside the drum. The hole has a gap between the opposing shaft member and regulates the axial position of the drum by thrust bearings inserted on both sides of the wall, and the pinion of the pinion which meshes the rotational axis of the drum with the tooth surface of the ring gear and the ring gear. A ring gear structure for a planetary gear of an automatic transmission, wherein the ring gear is aligned by aligning with a tooth surface.