JP2020003036A - Automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic transmission capable of downsizing the transmission in the axial direction. In an automatic transmission 2, a transmission case 4 has a transmission chamber 83 for accommodating a transmission 20 and a valve body chamber 84 for accommodating a valve body 42. The transmission chamber 83 is arranged above. The transmission case 4 has an upper wall 67, which surrounds the valve body 42 from above and separates the valve body chamber 84 from the transmission chamber 83, above the valve body chamber 84. A bearing holding portion 67A is formed on the upper wall 67. The bearing holding portion 67A holds the bearing 38F of the counter shaft 23 arranged in the transmission chamber 83. The bearing holder 67A bulges into the valve body chamber 84. [Selection diagram] Fig. 7

Description

  The present invention relates to an automatic transmission.

  2. Description of the Related Art Conventionally, as an automatic transmission mounted on a vehicle such as an automobile, there is known an automatic transmission in which a valve body is disposed below a transmission case (see Patent Document 1). In the device described in Patent Document 1, the height of the transmission case is reduced by disposing the counter shaft in the axial direction and disposing the valve body so as to overlap the output shaft in the axial direction. .

JP 2009-74621 A

  However, the one described in Patent Document 1 does not consider shortening the total length of the transmission case. Therefore, when trying to secure necessary dimensions of the valve body, the rotating shaft, and the like, the transmission case is moved in the axial direction. There was a problem that it would be long.

  The present invention has been made in view of the above circumstances, and has as its object to provide an automatic transmission that can reduce the size of the transmission in the axial direction.

  In order to achieve the above object, the present invention provides an automatic transmission including a transmission case having a transmission chamber for housing a transmission and a valve body chamber for housing a valve body, wherein The transmission chamber is disposed above, and the transmission case has an upper wall above the valve body chamber, surrounding the valve body from above, and separating the valve body chamber and the transmission chamber, A bearing holding portion for holding a bearing of a rotating shaft arranged in the transmission chamber and bulging into the valve body chamber is formed on the upper wall.

  As described above, according to the present invention, the transmission can be downsized in the axial direction.

FIG. 1 is a side view of an automatic transmission according to one embodiment of the present invention as viewed from the left side of a vehicle. FIG. 2 is a plan view of the automatic transmission according to one embodiment of the present invention. FIG. 3 is a sectional view taken in the direction of arrows III-III in FIG. 2. FIG. 4 is an enlarged sectional view of the torque converter housing and the front case of FIG. FIG. 5 is a cross-sectional view taken along a line VV in FIG. 1 in a state where a torque converter housing and parts related to a friction clutch are removed. FIG. 6 is a rear view of the front case of the automatic transmission according to one embodiment of the present invention. FIG. 7 is a sectional view taken along the line VII-VII in FIG. FIG. 8 is a sectional view taken along arrow VIII-VIII in FIG.

  An automatic transmission according to one embodiment of the present invention is an automatic transmission that includes a transmission case having a transmission chamber that houses a transmission and a valve body chamber that houses a valve body, the valve transmission comprising: A transmission chamber is disposed above the chamber, and the transmission case has an upper wall above the valve body chamber, surrounding the valve body from above, and separating the valve body chamber and the transmission chamber. A bearing holding portion that holds a bearing of the rotating shaft disposed in the transmission chamber and protrudes into the valve body chamber is formed. Thus, the automatic transmission according to one embodiment of the present invention can reduce the size of the transmission in the axial direction.

  Hereinafter, an automatic transmission according to an embodiment of the present invention will be described with reference to the drawings. 1 to 8 are views showing an automatic transmission according to an embodiment of the present invention. 1 to 8, the up, down, front, rear, and left and right directions indicate a vehicle traveling in a forward direction and a retreating direction in a rear direction. Further, the width direction of the vehicle is also referred to as a vehicle width direction.

  First, the configuration will be described. 1 and 2, an automatic transmission 2 is mounted on a vehicle 1. The automatic transmission 2 is mounted on a floor panel 1A of the vehicle 1 in a state where the automatic transmission 2 is fixed to a driving force source and an engine 3 as an internal combustion engine. It is installed vertically below. That is, the vehicle 1 of the present embodiment is a rear-wheel drive vehicle.

  The automatic transmission 2 includes a transmission case 4. The transmission case 4 includes a torque converter housing (hereinafter simply referred to as a torque converter housing) 5, a front case 6, a rear case 7, and an extension case 8. I have. The front end of the transmission case 4 is connected to the engine 3 by bolts (not shown). Of the transmission case 4, the front case 6, the rear case 7, and the extension case 8 excluding the torque converter housing 5 constitute a transmission case body 40. That is, the transmission case 4 includes the torque converter housing 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 refers to an operation for switching the gear position of the automatic transmission 2, and the clutch operation refers to engaging (connecting) or releasing (disconnecting) the friction clutch 17 (see FIG. 3) of the automatic transmission 2. Operation.

  3 and 4, a torque converter 10 is housed in the torque converter housing 5. The torque converter 10 includes a front cover 10A connected to a crankshaft (not shown) of the engine 3 and a shell 10B connected to the front cover 10A, and supplies power from the engine 3 to the automatic transmission 2 via oil. Is communicating.

  A pump impeller (not shown) is fixed to the inner surface of the shell 10B. A turbine runner (not shown) is installed inside the shell 10B so as to face the pump impeller, and the turbine runner is connected 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, in the torque converter 10, the front cover 10A, the shell 10B, and the pump impeller rotate integrally. At this time, a flow from the pump impeller to the turbine runner is generated in the fluid inside the torque converter 10 due to the centrifugal force due to the rotation of the pump impeller. The stator converts the flow of the fluid from the turbine runner along the rotation direction of the pump impeller. The torque converter 10 amplifies the power received from the engine 3 by a torque amplifying action and outputs the amplified power from the turbine shaft 11.

  A ring gear 10C is provided on the outer periphery of the shell 10B. The ring gear 10C transmits the rotation of the starter to the engine 3 when the pinion of the starter (not shown) is engaged when the engine 3 is started.

  The torque converter housing 5 has a peripheral wall 51 surrounding the torque converter 10 from the outer peripheral side, and a partition wall 55 provided inside the peripheral wall 51 and supporting the turbine shaft 11 between the torque converter 10 and the friction clutch 17. .

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

  An oil pump 12 is housed in the torque converter housing 5, and the oil pump 12 is formed of, for example, a trochoid type oil pump. The oil pump 12 includes a pump housing 12A. The pump housing 12A includes a second pump housing 14 fixed to the partition wall 55 by bolts (not shown) and a first pump fastened to the second pump housing 14 by bolts (not shown). And a housing 13. The first pump housing 13 and the second pump housing 14 constitute a housing of the oil pump 12. A pump chamber 15 is formed inside the first pump housing 13 and the second pump housing 14, and an inner rotor and an outer rotor (not shown) are provided in the pump chamber 15. The inner rotor is attached to the shell 10B via the impeller hub, and rotates integrally with the shell 10B.

  The outer rotor is provided radially outward of the inner rotor, and rotates with the rotation of the inner rotor. The trochoidal oil pump 12 forms an operating chamber (not shown) for accommodating oil between the external teeth and the internal teeth when the internal teeth formed on the outer rotor and the external teeth formed on the inner rotor come into contact with each other. .

  When the power of the engine 3 is transmitted to the inner rotor via the front cover 10A, in the oil pump 12, the inner rotor and the outer rotor rotate in one direction. At this time, as the volume of the working chamber increases and decreases continuously, 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 a rear end portion of the turbine shaft 11, and the flange portion 11A is formed to have a larger diameter than a front end portion and a central portion of the turbine shaft 11. An annular flywheel 16 is attached to the flange 11A. The flywheel 16 is a friction engagement element of the friction clutch 17. Therefore, the friction clutch 17 is connected to the turbine shaft 11. The flywheel 16 is housed in the front case 6.

  A friction clutch 17 and a transmission 20 are housed in the front case 6, and the friction clutch 17 faces the flywheel 16 in the axial direction.

  The front case 6 includes a peripheral wall 61 surrounding the friction clutch 17 and the transmission 20 from an outer peripheral side, a clutch chamber 82 in which the friction clutch 17 is accommodated, and a transmission chamber 83 in which the transmission 20 is accommodated. And a partition 65 for partitioning into two.

  The rear case 7 includes a peripheral wall 71 that surrounds the transmission 20 from an outer peripheral side, and a partition wall 75 that supports a rotation shaft of the transmission 20. The partition 75 is formed at the rear end of the rear case 7, and has an opening through which the output shaft 22 and the counter shaft 23 pass. The extension case 8 is attached to the rear end of the rear case 7, has an opening for taking out driving force from the output shaft 22, and seals the internal space of the transmission room 83.

  The friction clutch 17 is mounted near the front end 21a of the input shaft 21 in the axial direction. The input shaft 21 is housed in the front case 6 and the rear case 7, and is rotatably supported on the flange 11A via a bearing 38B at a front end 21a in the axial direction, and the output shaft 22 at a rear end 21b in the axial direction. It is supported rotatably.

  The output shaft 22 is disposed coaxially with the input shaft 21 behind the input shaft 21 in the axial direction of the input shaft 21. The output shaft 22 is rotatably supported by the partition 75 at the rear end of the rear case 7 and the extension case 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 disk 17A provided integrally rotatable with the input shaft 21 and movable in the axial direction of the input shaft 21, a pressure plate 17B for pressing the clutch disk 17A against the flywheel 16, and a pressure plate 17B. And a diaphragm spring 17C biasing the flywheel 16 side.

  The partition 65 of the front case 6 is formed with a tubular portion 66 through which the input shaft 21 passes. The tubular portion 66 extends from the vicinity of the center of the partition 65 along the axial direction of the input shaft 21 toward the friction clutch 17. Extends. That is, the tubular portion 66 is formed so as to protrude from the partition wall 65 toward the clutch chamber 82. The input shaft 21 is supported on the inner periphery of the cylindrical portion 66 via a bearing 38C.

  A release bearing 18 is provided on the outer peripheral portion of the cylindrical portion 66 so as to be adjacent to the friction clutch 17 in the axial direction. The release bearing 18 moves in the axial direction of the input shaft 21 and contacts and separates radially inward of the diaphragm spring 17C.

  When the release bearing 18 is moved forward in the axial direction of the input shaft 21 by the release lever 19, the release bearing 18 presses the radially inner end of the diaphragm spring 17C forward. As a result, the urging of the pressure plate 17B is released, and the clutch disc 17A is not pressed against the flywheel 16. As a result, the friction clutch 17 is released, and the rotation of the crankshaft of the engine 3 is not transmitted to the input shaft 21.

  When the release bearing 18 is moved rearward in the axial direction of the input shaft 21 by the release lever 19, the release bearing 18 separates from the radially inner end of the diaphragm spring 17C. At this time, the rotation of the flywheel 16 (the rotation of the crankshaft of the engine 3 via the torque converter 10) is applied to the input shaft by the diaphragm spring 17C urging the pressure plate 17B to press the clutch disk 17A against the flywheel 16. 21. As described above, 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 cutoff state.

  A counter shaft 23 is housed in the front case 6 and the rear case 7, and the counter shaft 23 is rotatably supported by the partition 65 of the front case 6 and the extension case 8. The counter shaft 23 extends parallel to the input shaft 21 and the output shaft 22.

  The input shaft 21 is provided with a fourth-speed input gear 24A, a third-speed input gear 24B, a second-speed input gear 24C, a first-speed input gear 24D, and a reverse input gear 24E from the friction clutch 17 toward the output shaft 22. .

  The fourth-speed input gear 24A, the third-speed input gear 24B, the second-speed input gear 24C, the first-speed input gear 24D, and the reverse input gear 24E are relatively rotatably connected to the input shaft 21.

  A fifth-speed clutch gear 22A is provided at a front end of the output shaft 22, and the fifth-speed clutch gear 22A is configured by a dog formed on an outer peripheral portion of the output shaft 22.

  The counter shaft 23 is provided with a fourth speed counter gear 26A, a third speed counter gear 26B, a second speed counter gear 26C, a first speed counter gear 26D, and a counter drive gear 26E from the friction clutch 17 side toward the output shaft 22. .

  The fourth-speed counter gear 26A, the third-speed counter gear 26B, the second-speed counter gear 26C, the first-speed counter gear 26D, and the counter drive gear 26E are fixed to the counter shaft 23.

  The fourth-speed counter gear 26A, the third-speed counter gear 26B, the second-speed counter gear 26C, and the first-speed counter gear 26D are respectively a fourth-speed input gear 24A, a third-speed input gear 24B, and a second-speed input gear 24C that constitute the same shift speed. , Is engaged with the first speed input gear 24D.

  The counter drive gear 26E meshes with the counter driven gear 27, and the counter driven gear 27 is fixed to the output shaft 22 so as to rotate integrally with the output shaft 22.

  The front case 6 and the rear case 7 accommodate a synchronizer 28 for the third and fourth speeds, a synchronizer 29 for the first and second speeds, and a synchronizer 30 for the reverse fifth and fifth speeds.

  The third-speed / fourth-speed synchronizer 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-and-select shaft 33 is operated, the third-speed / fourth-speed synchronizer 28 controls the input shaft 21 via the third-speed / fourth-speed shift shaft, shift yoke, and shift fork (not shown). It is moved in the axial direction.

  The first-speed / second-speed synchronizer 29 is rotatable integrally with the input shaft 21 and is provided movably in the axial direction of the input shaft 21. When the shift-and-select shaft 33 is operated, the first-second-speed synchronizer 29 is connected to the input shaft 21 via a first-second-speed shift shaft, a shift yoke, and a shift fork (not shown). It is moved in the axial direction.

  The synchronous device 30 for the reverse fifth speed 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-and-select shaft 33 is operated, the synchronizer 30 for the reverse fifth speed shifts in the axial direction of the input shaft 21 via a shift shaft, a shift yoke, and a shift fork (not shown). Moved to

  The third-speed / fourth-speed synchronizer 28 connects the fourth-speed input gear 24A to the input shaft 21 by moving from the neutral position to the front side in the axial direction of the input shaft 21 to establish the fourth forward speed. The power of the input shaft 21 is transmitted to the counter shaft 23 via the fourth speed input gear 24A and the fourth speed counter gear 26A.

  The power transmitted to the counter shaft 23 is transmitted from the counter drive gear 26E to the output shaft 22 via the counter driven gear 27. A differential device, a drive shaft, and a drive rear wheel (not shown) are connected to the output shaft 22 via a propeller shaft (not shown).

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

  The third-speed / fourth-speed synchronizer 28 moves the neutral position to the rear side in the axial direction of the input shaft 21 to connect the third-speed input gear 24B to the input shaft 21 to establish the third forward speed. The power of the input shaft 21 is transmitted to the counter shaft 23 via the third speed input gear 24B and the third speed counter gear 26B.

  The first-second-speed synchronizer 29 moves from the neutral position to the front side in the axial direction of the input shaft 21 to connect the second-speed input gear 24C to the input shaft 21 to establish the second forward speed. The power of the input shaft 21 is transmitted to the counter shaft 23 via the second speed input gear 24C and the second speed counter gear 26C.

  The first-gear second-speed synchronizer 29 connects the first-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 to establish the first forward gear. The power of the input shaft 21 is transmitted to the counter shaft 23 via the first speed input gear 24D and the first speed counter gear 26D.

  The reverse fifth gear synchronizer 30 moves the neutral position to the front side in the axial direction of the input shaft 21, thereby connecting the reverse input gear 24 </ b> E to the input shaft 21 to establish a reverse gear. The power is transmitted from the reverse input gear 24E to the counter shaft 23 via a reverse idler gear and a reverse output gear (not shown) and a first-speed counter gear 26D. At this time, since the counter shaft 23 rotates in the direction opposite to the rotation direction at the time of forward movement, the vehicle 1 moves backward.

  The reverse fifth speed synchronizing device 30 connects the fifth speed clutch gear 22A to the input shaft 21 by moving from the neutral position to the rear side in the axial direction of the input shaft 21 to establish the fifth forward speed. The power of the input shaft 21 is directly transmitted to the output shaft 22.

  The shift case 9 is provided above the front case 6, and the shift and select shaft 33 is provided inside the shift case 9. The shift and select shaft 33 extends in the vehicle width direction orthogonal to the direction in which the input shaft 21 extends.

  The shift and select shaft 33 is provided on the shift case 9 so as to be rotatable and movable in the axial direction, and is operated by a shift unit 100 connected to an end thereof.

  An oil pan 41 is attached to a lower part of the front case 6, and an oil storage chamber 43 for storing oil is formed inside the oil pan 41. The oil storage chamber 43 is arranged below the clutch chamber 82. A valve body 42 is accommodated between the oil pan 41 and the lower part of the front case 6, and the valve body 42 is fastened to the lower part of the front case 6 by bolts (not shown).

  The valve body 42 supplies the oil sucked from the oil pan 41 by the oil pump 12 to the torque converter 10 through the inside of the torque converter housing 5.

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

  Further, the valve body 42 supplies the oil sucked from the oil pan 41 by the oil pump 12 to a portion requiring lubrication such as the bearing 38 </ b> A through the inside of the torque converter housing 5.

  The release lever 19 is disposed on the side opposite to the friction clutch 17 with respect to the release bearing 18 in the axial direction of the automatic transmission 2. That is, the friction clutch 17 is arranged in front of the release bearing 18, while the release lever 19 is arranged behind the release bearing 18.

  The release lever 19 is connected to the shift unit 100 described above, and is operated by the shift unit 100. Specifically, the release lever 19 is swingably supported by using a fulcrum member attached to the partition wall 65 of the front case 6 as a swing fulcrum, and an end of the release lever 19 connected to the shift unit 100 has one end in the axial direction. , The end on the release bearing 18 side moves to the other end in the axial direction. The release lever 19 forms a release member in the present invention.

  More specifically, the release lever 19 is swingably supported by the partition wall 65 of the front case 6 at the swing center. One swing end 19A of the release lever 19 is connected to the release bearing 18, and the other swing end 19B of the release lever 19 is connected to the shift unit 100.

  In this embodiment, the operating force of the shift unit 100 is transmitted to the release bearing 18 by the swinging motion of the release lever 19, but the release member that transmits the operating force of the shift unit 100 to the release bearing 18 is as follows. The release lever 19 is not limited. For example, a member that transmits the operating force of the shift unit 100 to the release bearing 18 without swinging movement can be used as the release member.

  In FIG. 4, the front case 6 has a valve body chamber 84 above the oil storage chamber 43 that houses the valve body 42 continuously with the oil storage chamber 43, and separates the clutch chamber 82 and the valve body chamber 84. It has a ceiling wall 68. A rear end of the ceiling wall 68 is connected to a lower portion of the partition wall 65, a right end of the ceiling wall 68 is connected to a lower right portion of the peripheral wall 61, and a left end of the ceiling wall 68 is connected to a lower end of a vertical wall 69 described later. The front end of the ceiling wall 68 is connected to the lower part of the peripheral wall 61.

  As shown in FIGS. 4, 5, 6, 7, and 8, in the automatic transmission 2, the transmission case 4 includes a transmission chamber 83 that houses the transmission 20 and a valve that houses the valve body 42. And a body chamber 84.

  The transmission chamber 83 is disposed above the valve body chamber 84. The transmission case 4 has an upper wall 67 above the valve body chamber 84, and a front end of the upper wall 67 is connected to a lower part of the partition wall 65. The upper wall 67 surrounds the valve body 42 from above, and separates the valve body chamber 84 from the transmission chamber 83. That is, the ceiling wall 68, the upper wall 67, and the partition wall 65 are disposed in the upper part of the valve body chamber 84, and the valve body is provided with the ceiling wall 68 on the front side of the partition wall 65 and the upper wall 67 on the rear side of the partition wall 65. A chamber 84 is isolated.

  As shown in FIG. 7, a bearing holding portion 67A is formed on the partition wall 65 and the upper wall 67. The bearing holding portion 67A holds a bearing 38F at the front end of the counter shaft 23 disposed in the transmission chamber 83. A part (lower part) of a bearing holding part 67A is formed on the upper wall 67, and the bearing holding part 67A of the upper wall 67 is formed so as to be depressed downward along the outer diameter shape of the bearing 38F. It bulges into the chamber 84.

  As shown in FIG. 7, the upper wall 67 of the transmission case 4 has a gear housing portion 67B at a position adjacent to the rear of the bearing holding portion 67A. The gear housing portion 67B surrounds the fourth speed counter gear 26A provided on the counter shaft 23 from the outer peripheral side, and is formed to be recessed downward along the outer diameter of the fourth speed counter gear 26A. Swelling. The gear housing portion 67B is formed to have a larger diameter than the bearing holding portion 67A, and is formed in an arc shape coaxial with the bearing holding portion 67A around the bearing holding portion 67A when viewed from the axial direction of the counter shaft 23.

  The valve body chamber 84 is arranged at the bottom of the transmission case 4 (the front case 6). As shown in FIG. 8, the transmission case 4 (the front case 6) has a side wall 63 surrounding the valve body 42 from the side, and the side wall 63 extends downward from the peripheral wall 61. As shown in FIGS. 5 and 8, the side wall 63 and the bearing holding portion 67A are connected by a ceiling wall 68 and an upper wall 67, and the bearing holding portion 67A is connected to a joint between the rigid side wall 63 and the peripheral wall 61. Reinforced.

  As shown in FIG. 4, the transmission case 4 has a rear wall 64 extending vertically at a rear end of the valve body chamber 84. The rear wall 64 has its upper end connected to the rear end of the upper wall 67, surrounds the valve body 42 from behind, and separates the valve body chamber 84 from the transmission chamber 83. The rear wall 64 is connected to the gear housing 67B, and extends downward from the rear end of the gear housing 67B.

  As shown in FIG. 4, the valve body chamber 84 is arranged below the clutch chamber 82. The front part of the ceiling wall 68 forming the valve body chamber 84 is located below the rear part of the ceiling wall 68 in order to avoid interference with the friction clutch 17 and swells into the valve body chamber 84. The cylindrical portion 66 and the bearing holding portion 67A are connected at an upper wall 67.

  As shown in FIG. 5, the cylindrical portion 66 and the bearing holding portion 67A project from the partition wall 65 toward the friction clutch 17 and are connected by a rib 131 extending obliquely upward from the peripheral wall 61. A vertical wall 69 extending vertically is formed on the left side of the bearing holding portion 67A. The vertical wall 69 is a vertical wall that expands the valve body chamber 84 upward to form the breather chamber 44. Thus, the breather chamber 44 and the clutch chamber 82 are partitioned. The vertical wall 69 is formed in a trapezoidal shape when viewed from above so that the left side thereof is located forward of a portion near the cylindrical portion 66. The right end of the vertical wall 69 at an intermediate position in the vertical direction is connected to a cylindrical portion 66 that supports the input shaft 21, the lower portion of the vertical wall 69 is connected to a ceiling wall 68, and the right end is a bearing. It is connected to the holding section 67A.

  The bearing holding portion 67A holds a bearing 38F that supports the front end of the counter shaft 23. The gear surrounded by the gear housing 67B is a high-speed (fourth-speed) fourth-speed counter gear 26A. The fourth-speed counter gear 26A has the smallest diameter among the transmission gears arranged on the counter shaft 23.

  The clutch holding portion 82A side of the bearing holding portion 67A is reinforced by the rib 131 and the vertical wall 69. The gear oil flows inside the transmission chamber 83 to lubricate each part, and the torque converter oil flows inside the valve body chamber 84. Note that no oil exists inside the clutch chamber 82.

  Therefore, the transmission chamber 83 and the valve body chamber 84 are separated by the partition wall 65, the vertical wall 69, the upper wall 67, and the rear wall 64 so that these different types of oil are not mixed.

  As shown in FIGS. 3 and 4, the valve body 42 projects upward between the friction clutch 17 and the gear housing 67B in the axial direction of the input shaft 21. For this reason, the ceiling wall 68 forming the valve body chamber 84 is formed such that the rear part between the friction clutch 17 and the gear housing 67B is higher than the front part below the friction clutch 17. The rear part of the ceiling wall 68 is located between the friction clutch 17 and the gear storage part 67B. The rear end of the ceiling wall 68 is connected to the bearing holding portion 67A below the center position of the bearing holding portion 67A (the position of the axis of the counter shaft 23).

  In FIG. 5, a breather chamber 44 communicating with the oil storage chamber 43 above the oil storage chamber 43 behind the vertical wall 69 (rear side) by the vertical wall 69 and separating oil and air is provided in the front case 6. Is provided. The breather chamber is a vertically long space formed in the left part of the front case 6.

  The vertical wall 69 divides the clutch chamber 82 and the breather chamber 44. The vertical wall 69 extends upward from the upper surface of the ceiling wall 68. The vertical wall 69 is connected to the upper inner peripheral surface of the peripheral wall 61 of the front case 6.

  A breather pipe 136 is provided on the peripheral wall 61 above the breather chamber 44. The breather pipe 136 communicates the internal space of the breather chamber 44 with the outside of the front case 6. When the internal pressure of the oil storage chamber 43 increases, the air in the oil storage chamber 43 is separated from the oil when passing through the breather chamber 44 communicating with the oil storage chamber 43, and passes through the breather pipe 136 to the front case 6. Released to the outside.

  The input shaft 21 is supported on the inner periphery of the cylindrical portion 66 via a bearing 38C, and the vertical wall 69 is connected to the cylindrical portion 66. The counter shaft 23 is arranged below the transmission room 83 in parallel with the input shaft 21. The ceiling wall 68 is connected to a surface of the bearing holding portion 67A on the clutch chamber 82 side.

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

  As described above, in the present embodiment, the transmission case 4 has the transmission chamber 83 that houses the transmission 20 and the valve body chamber 84 that houses the valve body 42, and is located above the valve body chamber 84. , A clutch chamber 82 and a transmission chamber 83 are arranged.

  Further, the transmission case 4 includes a ceiling wall 68 which surrounds the valve body 42 from above and separates the valve body chamber 84 from the clutch chamber 82, and a valve body chamber 84 and a transmission chamber 83 above the valve body chamber 84. It has a separating upper wall 67. A bearing holding portion 67A is formed on the upper wall 67. The bearing holding portion 67A holds a bearing 38F of the counter shaft 23 disposed in the transmission chamber 83. The bearing holding portion 67A protrudes into the valve body chamber 84.

  Accordingly, the rear portion of the valve body 42 and the front end portion of the counter shaft 23 can be arranged to overlap (overlap) in the axial direction of the transmission 20, and the axial length of the transmission 20 can be reduced. Can be shorter. In addition, since the bearing holding portion 67A is formed so as to swell into the valve body chamber 84, the valve body 42 and the counter shaft 23 can be arranged closer to each other in the up-down direction. The length in the direction can be shortened.

  That is, since the rear part of the valve body 42 and the front end of the counter shaft 23 can be arranged so as to overlap when viewed from above, the front end of the counter shaft 23 can be arranged more forward than when they do not overlap. Therefore, the length of the transmission 20 in the axial direction can be reduced. As a result, the transmission 20 can be downsized in the axial direction.

  Further, in this embodiment, the transmission case 4 is formed at a position adjacent to the rear of the bearing holding portion 67A so as to have a larger diameter than the bearing holding portion 67A. There is a gear housing 67B that surrounds from the outer peripheral side.

  Thereby, a step is formed between the gear housing 67B and the periphery of the gear housing 67B, and the rigidity of the bearing holding part 67A can be improved by the bent shape and the vertical wall shape of the step. . Further, the fourth speed counter gear 26A provided on the counter shaft 23 held by the bearing holding portion 67A via the bearing 38F can also be disposed above the valve body chamber 84, and the transmission 20 can be further miniaturized in the axial direction. it can.

  In this embodiment, the valve body chamber 84 is disposed at the bottom of the transmission case 4. The transmission case 4 has a side wall 63 surrounding the valve body 42 from the side, and the side wall 63 is connected to the bearing holding portion 67A.

  Thereby, the rigidity of the bearing holding portion 67A can be improved.

  In this embodiment, the transmission case 4 surrounds the valve body 42 from the rear at the rear end of the valve body chamber 84 and continues to the side wall 63 to separate the valve body chamber 84 from the transmission chamber 83. It has a wall 64, and the rear wall 64 is connected to the rear end of the gear housing 67B.

  Thereby, the rigidity of the bearing holding portion 67A can be improved via the gear housing portion 67B.

  While embodiments of the present invention have been disclosed, it will be apparent that modifications may be made by those skilled in the art without departing from the scope of the invention. All such modifications and equivalents are intended to be included in the following claims.

2 ... automatic transmission, 4 ... transmission case, 20 ... transmission, 23 ... counter shaft (rotating shaft), 38F ... bearing, 42 ... valve body, 63 ... .Side wall, 67 ... Top wall, 67A ... Bearing holding part, 67B ... Gear storage part, 83 ... Transmission room, 84 ... Valve body room

Claims (4)

An automatic transmission having a transmission case having a transmission chamber for housing a transmission and a valve body chamber for housing a valve body,
The transmission chamber is disposed above the valve body chamber,
The transmission case has an upper wall above the valve body chamber, surrounding the valve body from above, and separating the valve body chamber and the transmission chamber from each other,
An automatic transmission, wherein a bearing holding portion that holds a bearing of a rotating shaft disposed in the transmission chamber and swells into the valve body chamber is formed on the upper wall.   The transmission case may include a gear storage portion formed at a position adjacent to the rear of the bearing holding portion and having a larger diameter than the bearing holding portion and surrounding a gear provided on the rotating shaft from an outer peripheral side. The automatic transmission according to claim 1, wherein: The valve body chamber is disposed at a bottom of the transmission case,
The transmission case has a side wall surrounding the valve body from a side,
The automatic transmission according to claim 1, wherein the side wall is connected to the bearing holding portion. The transmission case has a rear wall at a rear end of the valve body chamber, which surrounds the valve body from behind, and separates the valve body chamber from the transmission chamber.
The automatic transmission according to claim 2, wherein the rear wall is connected to the gear housing.

Images