CN110388444B

CN110388444B - Automatic transmission

Info

Publication number: CN110388444B
Application number: CN201910304352.9A
Authority: CN
Inventors: 更科俊平; 伊藤俊一; 岩井夏树
Original assignee: Suzuki Motor Corp
Current assignee: Suzuki Motor Corp
Priority date: 2018-04-18
Filing date: 2019-04-16
Publication date: 2022-08-30
Anticipated expiration: 2039-04-16
Also published as: FR3080423B1; CN110388444A; JP7087621B2; FR3080423A1; JP2019190477A; DE102019205200A1

Abstract

Provided is an automatic transmission in which a shift unit is attached to an outer wall of a transmission case, and in which vibration and noise generated in the transmission case can be reduced. The shift select shaft (33) and the bottom plate (101) are disposed at positions adjacent to the partition wall (65) in the direction along the input shaft (21), and the bottom plate (101) is fixed to the outer surface of the clutch chamber (82) and the outer surface of the transmission chamber (83) in the peripheral wall (61). A cylindrical portion (66) through which the input shaft (21) passes is formed in the partition wall (65) and protrudes toward the clutch chamber (82), and in a region where the bottom plate (101) is disposed in the direction along the input shaft (21), the inner surface of the peripheral wall (61), the partition wall (65), and the cylindrical portion (66) are connected by ribs (131), (132). A torque converter (10) is disposed on the axis of an input shaft (21), and a friction clutch (17) is coupled to the output side of the torque converter (10).

Description

Automatic transmission

Technical Field

The present invention relates to an automatic transmission.

Background

Conventionally, an automatic transmission mounted on a vehicle such as an automobile, which includes: a transmission case that rotatably supports an input shaft and the like; a clutch, a clutch lever, and a shift select shaft disposed within the transmission housing; and a shift unit that operates the clutch lever and the shift select shaft. In the automatic transmission described in patent document 1, the shift unit includes a base plate on which a case or the like including a transmission actuator and a clutch actuator is mounted, and the base plate is fixed to an outer wall of a transmission case.

Documents of the prior art

Patent literature

Patent document 1: japanese patent laid-open publication No. 2016-37257

Disclosure of Invention

Problems to be solved by the invention

Here, the outer wall of the transmission housing is required to have strength for fixing the bottom plate of the shift unit. In addition, when the inside of a fixing portion to which the bottom plate is fixed in the fixed transmission case is a spacious cavity, there is a possibility that the transmission case vibrates due to a load applied to the fixing portion from the bottom plate, or vibration or noise generated in the transmission case increases.

In the automatic transmission described in patent document 1, there is room for further study on suppression of vibration and noise of the transmission case.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an automatic transmission in which a shift unit is attached to an outer wall of a transmission case, and which can reduce vibration and noise generated in the transmission case.

Means for solving the problems

In order to achieve the above object, the present invention is an automatic transmission comprising: a friction clutch; a transmission having an input shaft for transmitting power from the friction clutch and a shift select shaft for speed change; a transmission case having a peripheral wall surrounding the friction clutch and the transmission from an outer peripheral side and a partition wall dividing an interior of the peripheral wall into a clutch chamber accommodating the friction clutch and a transmission chamber accommodating the transmission; and a shift unit having a bottom plate fixed to an outer surface of the peripheral wall, a clutch actuator for operating the friction clutch and a shift actuator for operating the shift select shaft being attached to the bottom plate, wherein the shift select shaft and the bottom plate are disposed at positions adjacent to the partition wall in a direction along the input shaft, and the bottom plate is fixed to an outer surface of the clutch chamber and an outer surface of the transmission chamber in the peripheral wall.

Effects of the invention

As described above, according to the present invention, in the automatic transmission in which the shift unit is attached to the outer wall of the transmission case, it is possible to reduce vibration and noise generated in the transmission case.

Drawings

Fig. 1 is a plan view of an automatic transmission according to an embodiment of the present invention.

Fig. 2 is a sectional view taken along line II-II of fig. 1.

Fig. 3 is a right side view of the automatic transmission of the embodiment of the invention as viewed from the vehicle right side.

Fig. 4 is an enlarged side view showing a right side surface of a front housing in a state where a shift unit is mounted of the automatic transmission of the embodiment of the present invention.

Fig. 5 is a front view of a front housing of the automatic transmission according to an embodiment of the present invention, as viewed from the front.

Fig. 6 is a rear view of the front housing of the automatic transmission of the embodiment of the present invention as viewed from the rear.

Fig. 7 is an enlarged side view showing a right side surface of a front housing in a state where only a bottom plate of a shift unit is attached, of an automatic transmission according to an embodiment of the present invention.

Fig. 8 is an enlarged side view showing a right side surface of a front housing in a state where a shift unit is not mounted of the automatic transmission of the embodiment of the present invention.

Fig. 9 is a view in cross section from direction IX-IX of fig. 5.

Fig. 10 is a cross-sectional view taken along the X-X direction in fig. 5.

Fig. 11 is a sectional view taken along line XI-XI of fig. 5.

Fig. 12 is a bottom view of the front case of the automatic transmission according to the embodiment of the present invention, as viewed from below, with the oil pan removed.

Description of the reference numerals

An automatic transmission, 4.. a transmission housing, 10.. a torque converter, 17.. a friction clutch, 20.. a transmission, 21.. an input shaft, 33.. a shift select shaft, 41.. an oil pan, 43.. an oil reservoir, 61.. a peripheral wall, 63.. a longitudinal wall, 63a.. a flange portion, 65.. a partition wall, 66.. a cylindrical portion, 82.. a clutch chamber, 83.. a transmission chamber, 100.. a shift unit, 101.. a bottom plate, 102.. a shift actuator, 103.. a clutch actuator, 131, 132.. a rib.

Detailed Description

An automatic transmission according to an embodiment of the present invention includes: a friction clutch; a transmission having an input shaft for transmitting power from the friction clutch and a shift select shaft for speed change; a transmission case having a peripheral wall surrounding the friction clutch and the transmission from an outer peripheral side and a partition wall dividing an interior of the peripheral wall into a clutch chamber housing the friction clutch and a transmission chamber housing the transmission; and a shift unit having a bottom plate fixed to an outer surface of the peripheral wall, a clutch actuator operating the friction clutch and a shift actuator operating the shift select shaft being mounted on the bottom plate, the shift select shaft and the bottom plate being disposed at positions adjacent to the partition wall in a direction along the input shaft, the bottom plate being fixed to an outer surface of the clutch chamber and an outer surface of the transmission chamber in the peripheral wall. Therefore, the automatic transmission according to the embodiment of the present invention can reduce vibration and noise generated in the transmission case.

[ examples ]

An automatic transmission according to an embodiment of the present invention will be described below with reference to the accompanying drawings. Fig. 1 to 12 are diagrams showing an automatic transmission of one embodiment of the present invention. In fig. 1 to 12, regarding the vertical, front, rear, left and right directions, when the direction in which the vehicle travels is defined as the forward direction and the backward direction is defined as the backward direction, the width direction of the vehicle is defined as the left and right directions, and the height direction of the vehicle is defined as the vertical direction. The width direction of the vehicle is also referred to as the vehicle width direction.

First, the configuration is explained. In fig. 1 and 3, an automatic transmission 2 is mounted on a vehicle 1, and the automatic transmission 2 is provided vertically below a floor panel 1A of the vehicle 1 in a state of being fixed to an engine 3 as a driving force source and an internal combustion engine. That is, the vehicle 1 of the embodiment is a rear-wheel drive vehicle.

The automatic transmission 2 includes a transmission case 4, and the transmission case 4 includes a torque converter case 5, a front case 6, a rear case 7, and an extension case 8. The front end portion of the transmission case 4 is connected to the engine 3 by a bolt not shown. The front housing 6, the rear housing 7, and the extension housing 8 in the transmission housing 4 other than the torque converter housing 5 constitute a transmission housing main body 40. That is, the transmission case 4 includes the torque converter case 5 and the transmission case main body 40.

The automatic transmission 2 includes a shift unit 100, and the shift unit 100 is driven to perform a shift operation and a clutch operation of the automatic transmission 2. Here, the shift operation is an operation of shifting the shift speed of the automatic transmission 2, and the clutch operation is an operation of engaging (connecting) or disengaging (disconnecting) the friction clutch 17 (see fig. 2) of the automatic transmission 2.

In fig. 2, a torque converter 10 is accommodated in the torque converter housing 5. The torque converter 10 includes: a front cover 10A coupled to a crankshaft, not shown, of the engine 3; and a case portion 10B coupled to the front cover 10A, the torque converter 10 transmitting power from the engine 3 to the automatic transmission 2 through oil.

A pump impeller (not shown) is fixed to an inner surface of the casing 10B. Inside the casing portion 10B, a turbine runner (turbine runner), not shown, is provided to face the pump impeller, and the turbine runner is coupled to the turbine shaft 11. A stator (not shown) is provided between the pump impeller and the turbine runner.

When the crankshaft of the engine 3 rotates, the front cover 10A, the case portion 10B, and the pump impeller rotate integrally in the torque converter 10. At this time, a centrifugal force generated by the rotation of the pump impeller generates a flow from the pump impeller to the turbine runner in the fluid inside the torque converter 10. The stator turns the flow of fluid from the turbine wheel into a direction of rotation along the pump wheel. The torque converter 10 amplifies the power received from the engine 3 by a torque amplification effect, and outputs it from the turbine shaft 11.

A ring gear 10C is provided in the outer periphery of the housing portion 10B. Ring gear 110C is engaged with a pinion of a starter, not shown, at the time of starting engine 3, and transmits the rotation of the starter to engine 3.

The torque converter case 5 has: a peripheral wall 51 surrounding the torque converter 10 from the outer peripheral side; and a partition wall 55 that is provided inside the peripheral wall 51 and supports the turbine shaft 11 between the torque converter 10 and the friction clutch 17.

The partition wall 55 partitions a torque converter chamber 81 inside the torque converter case 5 and a clutch chamber 82 inside the front housing 6. The turbine shaft 11 is rotatably supported by a bearing portion formed on the partition wall 55 via a bearing 38A.

An oil pump 12 is accommodated in the torque converter case 5, and the oil pump 12 is formed of, for example, a trochoid oil pump. The oil pump 12 includes a pump case 12A, and the pump case 12A includes: a 2 nd pump casing 14 fixed to the partition wall 55 by bolts not shown; and a 1 st pump casing 13 fastened to a 2 nd pump casing 14 by bolts not shown. The 1 st pump case 13 and the 2 nd pump case 14 constitute a case of the oil pump 12. Pump chamber 15 is formed inside first pump casing 13 and second pump casing 14, and an inner rotor and an outer rotor, not shown, are provided in pump chamber 15. The inner rotor is mounted to the shell portion 10B by an impeller hub (impeller hub) and rotates integrally with the shell portion 10B.

The outer rotor is disposed radially outward of the inner rotor and rotates with the rotation of the inner rotor. In the trochoidal oil pump 12, internal teeth formed in the outer rotor contact external teeth formed in the inner rotor, and a working chamber, not shown, that contains oil is formed between the external teeth and the internal teeth.

When the power of the engine 3 is transmitted to the inner rotor through the front cover 10A, the inner rotor and the outer rotor rotate in one direction in the oil pump 12. At this time, the volume increase and the volume decrease of the working chamber are continuously generated, so that the oil is sucked into the working chamber and the oil is discharged from the working chamber.

A disk-shaped flange portion 11A is formed at the rear end portion of the turbine shaft 11, and the flange portion 11A is formed to have a diameter larger than the front end portion and the center portion of the turbine shaft 11. An annular flywheel 16 is attached to the flange portion 11A. The flywheel 16 is accommodated in the front housing 6.

A friction clutch 17 and a transmission 20 are accommodated in the front housing 6, and the friction clutch 17 is axially opposed to the flywheel 16.

The front case 6 has: a peripheral wall 61 surrounding the friction clutch 17 and the transmission 20 from the outer peripheral side; and a partition wall 65 that divides the interior of the peripheral wall 61 into a clutch chamber 82 that houses the friction clutch 17 and a transmission chamber 83 that houses the transmission 20.

The rear case 7 has: a peripheral wall 71 surrounding the transmission 20 from an outer peripheral side; and a partition wall 75 that supports a rotation shaft of the transmission 20. The partition wall 75 is formed at the rear end of the rear housing 7 and seals the inner space of the peripheral wall 71.

The friction clutch 17 is attached near the axial front end 21a of the input shaft 21.

The input shaft 21 is accommodated in the front housing 6 and the rear housing 7, and is rotatably supported by the flange 11A via a bearing 38B at a front end 21A in the axial direction, and is rotatably supported by the output shaft 22 at a rear end 21B in the axial direction. The torque converter 10 is disposed on the axis of the input shaft 21, and the friction clutch 17 is coupled to the output side of the torque converter 10.

The output shaft 22 is opposed to the input shaft 21 in the axial direction of the input shaft 21. The output shaft 22 is rotatably supported by the partition wall 75 at the rear end portion of the rear housing 7 and the extension housing 8 via

bearings

38D and 38E, respectively. The output shaft 22 rotates relative to the input shaft 21.

The friction clutch 17 includes: a clutch disc 17A provided so as to be rotatable integrally with the input shaft 21 and movable in the axial direction of the input shaft 21; a pressure plate 17B that presses the clutch disc 17A to the flywheel 16; and a diaphragm spring 17C that biases the pressure plate 17B toward the flywheel 16.

A cylindrical portion 66 through which the input shaft 21 passes is formed in the partition wall 65 of the front housing 6, and the cylindrical portion 66 extends from the radially inner end of the partition wall 65 toward the friction clutch 17 along the axial direction of the input shaft 21. That is, the cylindrical portion 66 is formed to protrude from the partition wall 65 toward the clutch chamber 82 side. The input shaft 21 is supported on the inner periphery of the cylindrical portion 66 by a bearing 38C.

A release bearing 18 is provided on the outer peripheral portion of the cylindrical portion 66, and the release bearing 18 moves in the axial direction of the input shaft 21 so as to be in contact with and separated from the radially inner side of the diaphragm spring 17C.

The release bearing 18 presses the radially inner end portion of the diaphragm spring 17C forward if the release lever 19 moves forward in the axial direction of the input shaft 21. Accordingly, the biasing force on the pressure plate 17B is released, and the clutch disk 17A is separated from the flywheel 16. As a result, the rotation of the crankshaft of the engine 3 is no longer transmitted to the input shaft 21.

The release bearing 18 is separated from the radially inner end of the diaphragm spring 17C if moved rearward in the axial direction of the input shaft 21 by the release rod 19. At this time, the diaphragm spring 17C biases the pressure plate 17B to press the clutch disc 17A against the flywheel 16, thereby transmitting the rotation of the crankshaft of the engine 3 to the input shaft 21. In this way, the friction clutch 17 switches the power transmission state between the crankshaft of the engine 3 and the input shaft 21 to the transmission state or the blocking state. The release lever 19 is coupled to the above-described shift unit 100, and is operated by the shift unit 100.

An intermediate shaft 23 is accommodated between the front housing 6 and the rear housing 7, and the intermediate shaft 23 is rotatably supported by the

partition walls

65 and 75. The intermediate shaft 23 extends parallel to the input shaft 21 and the output shaft 22.

The input shaft 21 is provided with a 4-speed input gear 24A, a 3-speed input gear 24B, a 2-speed input gear 24C, a 1-speed input gear 24D, and a reverse input gear 24E from the friction clutch 17 side toward the output shaft 22.

The 4-speed input gear 24A, the 3-speed input gear 24B, the 2-speed input gear 24C, the 1-speed input gear 24D, and the reverse input gear 24E are coupled to the input shaft 21 and are relatively rotatable.

A 5-speed clutch gear 22A is provided at a distal end portion of the output shaft 22, and the 5-speed clutch gear 22A includes a dog (dog) formed on an outer peripheral portion of the output shaft 22.

The intermediate shaft 23 is provided with a 4-speed intermediate gear 26A, a 3-speed intermediate gear 26B, a 2-speed intermediate gear 26C, a 1-speed intermediate gear 26D, and an intermediate drive gear 26E from the friction clutch 17 side toward the output shaft 22.

The 4-speed idler gear 26A, the 3-speed idler gear 26B, the 2-speed idler gear 26C, the 1-speed idler gear 26D, and the idler drive gear 26E are fixed to the countershaft 23.

The 4-speed, 3-speed, 2-speed, and 1-speed intermediate gears 26A, 26B, 26C, and 26D mesh with the 4-speed, 3-speed, 2-speed, and 1-speed input gears 24A, 24B, 24C, and 24D, respectively, that constitute the same shift speed.

The intermediate drive gear 26E meshes with an intermediate driven gear 27, and the intermediate driven gear 27 is fixed to the output shaft 22 and rotates integrally with the output shaft 22.

The front housing 6 and the rear housing 7 accommodate a 3-gear-4-gear synchronizer 28, a 1-gear-2-gear synchronizer 29, and a reverse-5-gear synchronizer 30.

The 3 rd-4 th synchronization device 28 is provided so as to be rotatable integrally with the input shaft 21 and to be movable in the axial direction of the input shaft 21. When the shift select shaft 33 is operated, the 3-speed-4-speed synchronizer 28 is moved in the axial direction of the input shaft 21 by a shift shaft, a shift fork (shift fork), and a shift fork (shift fork), all not shown.

The 1 st-2 nd synchronizer 29 is provided so as to be rotatable integrally with the input shaft 21 and to be movable in the axial direction of the input shaft 21. When the shift select shaft 33 is operated, the 1 st-2 nd synchronizer 29 is moved in the axial direction of the input shaft 21 by a shift shaft, a shift fork, and a shift fork for 1 st-2 nd, all of which are not shown.

The synchronization device 30 for reverse-5 is provided so as to be rotatable integrally with the input shaft 21 and to be movable in the axial direction of the input shaft 21. When the shift select shaft 33 is operated, the synchronizer 30 for reverse-5 is moved in the axial direction of the input shaft 21 by a shift shaft for reverse-5, a shift fork, and a shift fork, all of which are not shown.

The 3-speed-4-speed synchronizer 28 is moved from the neutral position to the front side in the axial direction of the input shaft 21, thereby connecting the 4-speed input gear 24A to the input shaft 21 to establish the forward 4-speed, and transmitting the power of the input shaft 21 to the counter shaft 23 through the 4-speed input gear 24A and the 4-speed counter gear 26A.

The power transmitted to the intermediate shaft 23 is transmitted from the intermediate drive gear 26E to the output shaft 22 through the intermediate driven gear 27. A differential device, a drive shaft, and a driven rear wheel, all not shown, are coupled to the output shaft 22 via a propeller shaft, not shown.

Accordingly, the power transmitted to the output shaft 22 is transmitted to the differential device through the propeller shaft, and then distributed to the left and right drive shafts by the differential device, and transmitted from the drive shafts to the driven rear wheels. As a result, the vehicle 1 travels.

The 3-speed-4-speed synchronizer 28 is moved from the neutral position to the rear side in the axial direction of the input shaft 21, thereby connecting the 3-speed input gear 24B to the input shaft 21 to establish the forward 3-speed, and transmitting the power of the input shaft 21 to the counter shaft 23 through the 3-speed input gear 24B and the 3-speed counter gear 26B.

The 1 st-2 nd synchronizer 29 connects the 2 nd input gear 24C to the input shaft 21 by moving from the neutral position to the front side in the axial direction of the input shaft 21, establishes the forward 2 nd gear, and transmits the power of the input shaft 21 to the counter shaft 23 through the 2 nd input gear 24C and the 2 nd intermediate gear 26C.

The 1 st-2 nd synchronizer 29 connects the 1 st-gear input gear 24D to the input shaft 21 by moving from the neutral position to the rear side in the axial direction of the input shaft 21, thereby establishing the forward 1 st gear, and transmits the power of the input shaft 21 to the counter shaft 23 through the 1 st-gear input gear 24D and the 1 st-gear counter gear 26D.

The synchronization device 30 for reverse-5 is moved from the neutral position to the axial forward side of the input shaft 21, thereby connecting the reverse input gear 24E to the input shaft 21 to establish a reverse gear, and the power of the input shaft 21 is transmitted from the reverse input gear 24E to the intermediate shaft 23 through a reverse idle gear, a reverse output gear, and a 1 st intermediate gear 26D, all of which are not shown. At this time, the intermediate shaft 23 rotates in the direction opposite to the rotation direction at the time of forward movement, and therefore the vehicle 1 moves backward.

The synchronizer 30 for reverse-5 is moved from the neutral position to the rear side in the axial direction of the input shaft 21, thereby connecting the 5-speed clutch gear 22A to the input shaft 21 to establish the forward 5-speed, and directly transmitting the power of the input shaft 21 to the output shaft 22.

A shift case 9 is provided on an upper portion of the front housing 6, and a shift select shaft 33 is provided inside the shift case 9. The shift select shaft 33 extends in the vehicle width direction orthogonal to the extending direction of the input shaft 21.

The shift select shaft 33 is provided in the shift case 9 to be freely rotatable and movable in the axial direction, and is operated by the shift unit 100 coupled to an end portion thereof.

An oil pan 41 is mounted on a lower portion of the front case 6, and an oil reservoir chamber 43 for storing oil is formed inside the oil pan 41. Further, a valve body 42 is accommodated between the oil pan 41 and the lower portion of the front housing 6, and the valve body 42 is fixed to the lower portion of the front housing 6.

The valve body 42 supplies the oil drawn up from the oil sump 41 by the oil pump 12 to the torque converter 10 through the inside of the torque converter case 5.

The oil supplied to the torque converter 10 is used as oil for engaging or releasing a lock-up clutch, not shown, of the torque converter 10 or as oil flowing from the pump impeller to the turbine runner.

The valve body 42 supplies the oil sucked up from the oil pump 12 from the oil pan 41 to a portion requiring lubrication, such as the bearing 38A, through the inside of the torque converter case 5.

In fig. 3 and 4, a shift unit 100 is attached to a right side surface of the peripheral wall 61 of the front housing 6. The shift unit 100 has: a reserve tank (reserve tank)104 that stores oil; an oil pump 105 that boosts the pressure of oil supplied from the reserve tank 104; an electric motor 106 that drives the oil pump 105; and an accumulator 107 that accumulates the pressure of the oil boosted by the oil pump 105.

Further, the shift unit 100 includes: a shift actuator 102 that operates the shift select shaft 33; a clutch actuator 103 that operates the friction clutch 17; and a control device 108 that controls these shift actuator 102 and clutch actuator 103. The control device 108 has an oil passage switching valve such as a solenoid valve, not shown, and drives the shift actuator 102 and the clutch actuator 103 by switching a supply path of the oil from the accumulator 107 to the shift actuator 102 and the clutch actuator 103 by the oil passage switching valve.

In addition, the shift unit 100 has a base plate 101 on which a shift actuator 102, a clutch actuator 103, and the like are mounted. The bottom plate 101 is formed in a rectangular flat plate shape in side view and fixed to the outer surface of the peripheral wall 61. In the present embodiment, the bottom plate 101 is fixed to the right side surface of the peripheral wall 61.

The shift unit 100 has a 1 st fixing portion 101A, a 2 nd fixing portion 101B, a 3 rd fixing portion 101C, and a 4 th fixing portion 101D to be fixed to the outer surface of the peripheral wall 61 by fastening. The 1 st fixing section 101A is disposed at the upper end of the base plate 101 and near the front end, and the 4 th fixing section 101D is disposed at the upper end of the base plate 101 and near the rear end. The 2 nd fixing portion 101B is disposed at the lower end of the bottom plate 101 and near the front end, and the 3 rd fixing portion 101C is disposed at the lower end of the bottom plate 101 and near the rear end.

On the other hand, on the outer surface of the peripheral wall 61, a 1 st fixed part 61A, a 2 nd fixed part 61B, a 3 rd fixed part 61C, and a 4 th fixed part 61D to which the bottom plate 101 is fixed by fastening are formed.

The 1 st fixed part 61A, the 2 nd fixed part 61B, the 3 rd fixed part 61C, and the 4 th fixed part 61D are disposed at positions corresponding to the 1 st fixed part 101A, the 2 nd fixed part 101B, the 3 rd fixed part 101C, and the 4 th fixed part 101D, respectively. Here, "fixed by fastening" means fixed by a bolt or fixed by a double-headed bolt and a nut.

In fig. 10, the 1 st fixed part 61A and the 4 th fixed part 61D are formed in a boss shape protruding toward the bottom plate 101. Similarly, as shown in fig. 5 and 6, the 2 nd fixing object 61B and the 3 rd fixing object 61C are formed in a boss shape protruding toward the bottom plate 101.

In fig. 7 and 9, the bottom plate 101 is disposed adjacent to the partition wall 65 in the direction (axial direction) along the input shaft 21.

In fig. 7, 8, and 9, a bottom plate 101 is fixed to an outer surface of the clutch chamber 82 and an outer surface of the transmission chamber 83 in the peripheral wall 61.

In fig. 9, the shift select shaft 33 is disposed adjacent to the partition wall 65 in the direction (axial direction) along the input shaft 21.

In fig. 5 and 11, in the region where the bottom plate 101 is disposed along the direction of the input shaft 21, the inner surface of the peripheral wall 61, the partition wall 65, and the cylindrical portion 66 are connected by

ribs

131 and 132. The

ribs

131 and 132 extend in a radial direction around the input shaft 21.

In fig. 5 and 6, the partition wall 65 includes

support portions

65B and 65C. In the supporting

portions

65B and 65C, the surface of the partition wall 65 on the transmission chamber 83 side is recessed, and the surface of the partition wall 65 on the clutch chamber 82 side is protruded. The support portion 65B supports the front end portion of the intermediate shaft 23 by a bearing, and the support portion 65C supports the front end portion of the reverse shaft 34 by a bearing.

In fig. 5, 6, and 12, the oil reservoir chamber 43 includes: an oil pan 41 disposed below a region in the peripheral wall 61 where the clutch chamber 82 is formed and the bottom plate 101 is fixed; a vertical wall portion 63 extending downward from the lower surface of the peripheral wall 61 toward the peripheral edge portion of the oil pan 41; and a flange portion 63A formed at the lower end of the vertical wall portion 63 and joined to the oil pan 41. As shown in fig. 12, the vertical wall portion 63 is formed in an annular or rectangular shape when the transmission case 4 is viewed from below. That is, when the transmission case 4 is viewed from below, the vertical wall portion 63 is not formed in a linear or arc shape, but is formed in a shape surrounding the oil reservoir chamber 43, and forms a closed region (oil reservoir chamber 43) inside thereof.

Next, the effects of the automatic transmission 2 configured as described above will be described.

In the automatic transmission 2 of the present embodiment, the shift select shaft 33 and the bottom plate 101 are disposed at positions adjacent to the partition wall 65 in the direction along the input shaft 21, and the bottom plate 101 is fixed to the outer surface of the clutch chamber 82 and the outer surface of the transmission chamber 83 in the peripheral wall 61.

As described above, in the present embodiment, since shift select shaft 33 and base plate 101 are disposed at positions adjacent to partition wall 65 in the direction along input shaft 21, most of base plate 101 can be disposed on the outer wall of clutch chamber 82.

Further, since the bottom plate 101 is fixed to the outer wall of the clutch chamber 82 and the outer wall of the transmission chamber 83, the bottom plate 101 can be fixed to a portion of the transmission case 4 in which the partition wall 65 is disposed, the portion having relatively high rigidity, and therefore vibration of the transmission case 4 to which the bottom plate 101 is attached can be suppressed.

In addition, in the transmission case 4, the cross section of the transmission case 4 in the clutch chamber 82 is larger than the cross section of the transmission case 4 in the transmission chamber 83, and therefore, by fixing a part of the bottom plate 101 to the outer wall of the clutch chamber 82, the bottom plate 101 can be stably supported, and vibration of the shift unit 100 can be suppressed.

As a result, in the automatic transmission 2 in which the shift unit 100 is attached to the outer wall of the transmission case 4, vibration and noise generated in the transmission case 4 can be reduced.

In the automatic transmission 2 of the present embodiment, the cylindrical portion 66 through which the input shaft 21 passes is formed in the partition wall 65, the cylindrical portion 66 protrudes toward the clutch chamber 82 side, and the inner surface of the peripheral wall 61, the partition wall 65, and the cylindrical portion 66 are coupled by the

ribs

131, 132 in the region where the bottom plate 101 is disposed in the direction along the input shaft 21.

In this way, in the present embodiment, the

ribs

131 and 132 increase the rigidity of the region of the inner wall of the clutch chamber 82 where the base plate 101 is fixed, and vibration of the outer wall of the transmission case 4 can be suppressed. Therefore, vibration and noise generated in the transmission case 4 can be reduced.

In the automatic transmission 2 of the present embodiment, the torque converter 10 is disposed on the axis of the input shaft 21, and the friction clutch 17 is coupled to the output side of the torque converter 10. The transmission case 4 has an oil reservoir chamber 43 for storing oil supplied to the torque converter 10, and the oil reservoir chamber 43 includes: an oil pan 41 disposed below a region in the peripheral wall 61 where the clutch chamber 82 is formed and the bottom plate 101 is fixed; a vertical wall portion 63 extending downward from the lower surface of the peripheral wall 61 toward the peripheral edge portion of the oil pan 41; and a flange portion 63A formed at the lower end of the vertical wall portion 63 and joined to the oil pan 41.

As described above, in the present embodiment, the vertical wall portion 63 having the flange portion 63A with high rigidity is disposed below the region of the peripheral wall 61 where the clutch chamber 82 is formed and the bottom plate 101 is fixed, and therefore, the rigidity of the peripheral wall 61 in this region can be increased, and vibration of the outer wall of the transmission case 4 can be suppressed. Therefore, vibration and noise generated in the transmission case 4 can be reduced.

In the automatic transmission 2 of the present embodiment, the vertical wall portion 63 is formed in an annular or rectangular shape when the transmission case 4 is viewed from below.

In this way, in the present embodiment, since the vertical wall portion 63 is formed in a ring shape or a rectangular shape, the rigidity of the vertical wall portion 63 can be increased in the vehicle front-rear direction and the vehicle width direction. Therefore, vibration and noise generated in the transmission case 4 can be reduced.

Although embodiments of the present invention have been disclosed, it is apparent that modifications can be made by those skilled in the art without departing from the scope of the invention. It is intended that all such modifications and equivalents be included in the following claims.

Claims

1. An automatic transmission having:

a friction clutch;

a transmission having an input shaft for transmitting power from the friction clutch and a shift select shaft for speed change;

a transmission case having a peripheral wall surrounding the friction clutch and the transmission from an outer peripheral side and a partition wall dividing an interior of the peripheral wall into a clutch chamber accommodating the friction clutch and a transmission chamber accommodating the transmission; and

a shift unit having a base plate fixed to an outer surface of the peripheral wall, a clutch actuator for operating the friction clutch and a shift actuator for operating the shift select shaft being attached to the base plate, the shift unit being characterized in that,

the shift select shaft is disposed adjacent to the partition wall in a direction along the input shaft,

the bottom plate is disposed across the partition wall in a direction along the input shaft, and is fixed to an outer surface of the clutch chamber and an outer surface of the transmission chamber in the peripheral wall.

2. The automatic transmission of claim 1,

a cylindrical portion through which the input shaft passes is formed on the partition wall, and the cylindrical portion protrudes toward the clutch chamber,

in a region where the bottom plate is disposed along the direction of the input shaft, the inner surface of the peripheral wall, the partition wall, and the cylindrical portion are connected by a rib.

3. The automatic transmission according to claim 1 or claim 2,

a torque converter is disposed on an axis of the input shaft,

the friction clutch is coupled to an output side of the torque converter,

the transmission case has an oil reservoir chamber that stores oil supplied to the torque converter,

the oil storage chamber includes: an oil pan disposed below a region of the peripheral wall that forms the clutch chamber and to which the bottom plate is fixed; a vertical wall portion extending downward from a lower surface of the peripheral wall toward a peripheral edge portion of the oil pan; and a flange portion formed at a lower end of the vertical wall portion and joined to the oil pan.

4. The automatic transmission of claim 3,

the vertical wall portion is formed in an annular or rectangular shape when the transmission case is viewed from below.