JPH0226103B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to an automatic transmission. (Prior Art) Conventionally, an automatic transmission is provided with a plurality of planetary gear sets, and each element of the planetary gear set is selectively connected to form various gear stages. Therefore, multi-disc brakes, multi-disc clutches, etc. are provided to releasably connect the elements of the planetary gear set to each other, or between the elements of the planetary gear set and stationary members such as the transmission case. Among these, first and reverse brake
B ₃ is connected between the carrier of the second planetary gear set and the transmission case,
It is arranged to engage and fix the carrier during 1st gear in the L range and during reverse. The carrier of the second planetary gear set has a one-way clutch to prevent it from rotating to the left, and therefore the fast-and-reverse brake _B3 has a fixed plate connected to the transmission case. The thin plate on the movable side is connected to the outer race of one-way clutch _F2 . Furthermore, the inner race of the one-way clutch _F2 is connected to a fixing member disposed near the transmission shaft. (Problems to be Solved by the Invention) However, in the automatic transmission having the above configuration, the load applied to the brakes, especially the first and reverse brake _B3 that is engaged when reversing the vehicle, is large; The one-way clutch _F2 disposed between the stored and reverse brake _B3 and the fixed member may tilt. In other words, it is necessary to provide the first and reverse brake B ₃ with an engagement force sufficient to withstand the load applied when moving backward, and the hydraulic servo
The pressure oil supplied to b ₃ is set higher than normal. As mentioned above, the outer race of the one-way clutch _F2 is connected to the movable thin plate of the fast-and-reverse brake _B3 , and the inner race of the one-way clutch _F2 is connected to the fixed member disposed near the transmission shaft. But above hydraulic servo B ₃
The thin plate of the first and reverse brake _B3 is pressed by the hydraulic pressure supplied to the brake, which may cause it to tilt. If this one-way clutch _F2 is tilted and rotates freely, the movable parts of the fast and reverse brake _B3 will not be able to rotate smoothly. The present invention solves the problems of the conventional automatic transmission described above, and provides a first and reverse brake _B3 .
One-way clutch installed between the
The objective is to provide an automatic transmission that can improve the durability of the _F2 and reduce the weight of the transmission. (Means for solving the problem) For this purpose, in the automatic transmission of the present invention,
It has an intermediate support wall that integrally extends radially inward from the transmission case, and a cylindrical center support that integrally extends from the intermediate support wall in the axial direction to support the transmission shaft of the automatic transmission. A hydraulic servo for the first and reverse brake is disposed in the space formed between the transmission case, the intermediate support wall, and the center support. The hydraulic servo is equipped with a first and reverse brake that is engaged and disengaged by supplying and discharging hydraulic pressure. A one-way clutch that allows rotation in only one direction is disposed between the first and reverse brake and the center support,
A spline engagement is provided between the inner race of the one-way clutch and the center support. (Operations and Effects of the Invention) According to the present invention, as described above, the intermediate support wall integrally extends radially inward from the transmission case, and the intermediate support wall integrally extends in the axial direction from the intermediate support wall. It has a cylindrical center support that supports the transmission shaft of the transmission, and the hydraulic servo of the first and reverse brake is arranged in the space formed between the transmission case, intermediate support wall, and center support. The hydraulic servo is equipped with a first-and-reverse brake that is engaged and released by supplying and discharging hydraulic pressure. Since all of the wall parts that form the hydraulic servo are integrated, the structure of the hydraulic servo is strong, ensuring reliable operation, and the transmission case is also lightweight. be able to. Further, a one-way clutch that allows rotation in only one direction is disposed between the first and reverse brake and the center support, and an inner race of the one-way clutch and the center support are spline engaged. Therefore, the axial deviation between the center support and the one-way clutch can be absorbed by the spline engagement. Therefore, the one-way clutch is not tilted by the hydraulic pressure supplied to the hydraulic servo.
The one-way clutch is not damaged during free rotation, improving durability. Moreover, rotation can always be transmitted smoothly. (Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings. Figure 1 shows the front engine/front drive type (FF type) of the automatic transmission of the present invention.
FIG. 2 is a diagram showing an example applied to a car. In the figure, 1 is a fluid torque converter with a direct coupling clutch connected to the output shaft of the engine, 2 is a gear transmission with 4 forward speeds and 1 reverse speed, 3 is a differential device connected to the axle, and 4 is a gear transmission 2. This is a speed reduction mechanism provided between the differential gear 3 and the differential gear 3. Further, the torque converter 1 is installed in a torque converter case 5 whose front side (engine side) is open, and the gear transmission 2 is housed in a transmission case 6 connected to the rear end 5A of the torque converter case 5. ing. At the rear of the torque converter case 5, an output gear room 51 for holding an output gear of the gear transmission 2 is provided in the center. Further, the reduction mechanism room 52 is formed around the circumference, and a governor room 53 that houses the governor oil pressure generating mechanism 11 is formed, and a differential device room 54 is formed on the side of the torque converter case 5. It is formed. The rear end of the transmission case is covered with a rear cover 60, and an oil pump 12 is mounted on the outer surface of the rear cover 60.
An oil pump cover 61 in which is housed is fastened. The torque converter 1 includes a pump impeller 14 connected to the engine output shaft through a front cover 13, a turbine runner 16 connected to the output shaft 7 of the hollow torque converter through a turbine hub 15, and a one-way clutch 17. It consists of a stator 18 engaged with a fixed part and a direct coupling clutch 19 connected to the turbine hub. The transmission case 6 has openings 65 and 66 of the same shape at the torque converter side (front side) end 6A and rear side end 6B, and around these openings 65 and 66, there is a flange surface 6 of the same shape.
7 and 68 are extended, and from the flange surfaces 67 and 68, spigot parts 69 and 70 of approximately the same size are formed extending in the axial direction.
Also, inside there is a cylindrical center support 62 in the center.
It has an intermediate support wall 63 provided with a rear opening 6
A rear center support 64 having the same axis as the center support is formed in the center of the rear cover 60 which is attached to the rear cover 60. The gear transmission 2 is operated by a first planetary gear set 23 disposed at the rear of the intermediate support wall 63, a second planetary gear set 24 disposed at the front of the intermediate support wall 63, and a hydraulic servo. Three multi-disc clutches C ₁ , C ₂ , C 3 that connect, engage and release the elements of each planetary gear set _, three multi-disc brakes B ₁ , B ₂ , B ₃ and three one-way clutches F ₀ , F ₁ , _F2 . The output shaft 7 of the torque converter, which is the input shaft of the gear transmission 2, has an annular shape that is pivotally supported by a rear center support 64 at its rear end and rotatably fitted around the rear center support 64 near its rear end. It is spline-fitted to the rear drum 25 for the hydraulic servo. The rear drum 25 for hydraulic servo is open at the front and has an intermediate cylinder wall 251.
An annular piston 254 is fitted between the intermediate cylindrical wall 251 and an inner circumferential wall 252 externally fitted on the rear center support 64 to form an annular hydraulic servo c ₁ of the clutch C ₁ . Cylinder wall 25
1 and the outer peripheral wall 253 is an annular piston 253.
is fitted to form the hydraulic servo _C2 of the clutch _C2 . The first planetary gear set 23 is a multi-plate clutch formed in the intermediate cylindrical wall 251 of the drum.
A sun gear 231 connected to the rear drum 25 via _C1 , a carrier 232 spline-fitted to the output shaft 9 of the gear transmission 2 coaxially arranged outside the input shaft 7, and an outer peripheral wall of the drum. It is spline-fitted to the hollow first intermediate shaft 26 of the gear transmission ₂ , which is connected to the rear drum 25 via a multi-plate clutch C2 formed inside and coaxially arranged outside the output shaft 9. ring gear 2
33, and a planetary gear 234 rotatably supported by the carrier 232 and meshed with the sun gear 231 and the ring gear 233. The intermediate support wall 63 has an annular cylinder 6 on the front surface.
31 is formed, and an annular piston 632 is fitted into the hydraulic cylinder 631 to form a hydraulic servo _b3 for operating the brake _B3 . Further, an annular protrusion 633 is provided on the rear surface of the intermediate support wall 63.
An annular cylinder 634 is provided on the outer peripheral side of the annular protrusion, and a hydraulic servo b ₁ is formed in which an annular piston 635 is fitted to operate the brake B ₁ .
An annular cylinder 636 is formed on the inner peripheral side of the brake 33, and an annular piston 637 is fitted into the hydraulic servo _b2 for operating the brake _B2.
is formed. Inside _the intermediate support wall _{63 ,} as shown in _FIG .
01, 102, 103, and 104 are formed, and a lubricating oil passage 105 is also formed. Oil passages 101 and 102 are connected to hydraulic servos b ₁ and b ₂ via horizontal holes 106 and 107 formed at the rear, respectively.
The oil passage 103 supplies hydraulic oil to the hydraulic servo _b3 through a horizontal hole 108 formed in the front. Hydraulic pressure is supplied to the hydraulic servo c ₃ through an oil passage 109 formed by an axial groove 621 formed in the inner wall of the center support 62 and a partition sleeve 620 fitted into the center support 62 and the center support. A radial hole 100 formed in the rear end of 62
through. Further, lubricating oil from the lubricating oil passage 105 is supplied from an oil hole 622 formed in the sleeve 620. The second planetary gear set 24 is connected to the first intermediate shaft 26, and includes a carrier 241 fixed to the outer race of a one-way clutch _F2 that engages the transmission case 6 via a brake _B3 , and an output shaft 9. A sun gear 24 is formed at the tip of a second output shaft 27 rotatably supported between the ring gear 242 spline-fitted to the first intermediate shaft 26 and the center support 62.
3. Consists of a planetary gear 244 rotatably supported by a carrier 241 and meshed with a sun gear 243 and a ring gear 242. The one-way clutch _F2 is as shown in Figure 3.
An inner spline 201 is formed on the inner race 200, and is spline-fitted to an outer spline 202 formed on the outer periphery of the tip of the center support 62 to maintain a predetermined minute play and is attached to the center support 62. ing. The one-way clutch _F2 is located inside the first and reverse brake _B3 . As described above, the axial and radial misalignment between the center support 62 and the one-way clutch _F2 can be absorbed by the spline fitting. Therefore, the one-way clutch F2 will not tilt due to the hydraulic pressure supplied to the hydraulic servo _b3 , and the one- _way clutch _F2 will not tilt during free rotation.
There is no chance of damage, and durability is improved. Then, the frictional engagement elements of the one-way clutch _F2 and the first-and-reverse brake _B2 rotate smoothly. Furthermore, an inner race f ₁ of a one-way clutch F ₀ is spline-fitted to the rear end of the second output shaft 27, and an inner race of the one-way clutch F ₁ is rotatably fitted to the rear end of the center support 62. It is formed integrally with f ₂ to constitute a common inner race 29. Above center support 62 and one-way clutch
Spline fitting with F ₂ is the center support 6
The transmission case 6 containing the one-way clutch F ₂ is usually made of aluminum alloy.
Since the inner race is made of cast iron, the splines formed on the center support 62, which has low mechanical strength, have a narrow groove width, and the splines formed on the inner race 200, which has high mechanical strength, have a wide groove width. The groove width ratio is set to 1:2 or more and 1:4 or less, preferably 1:3, and the number of splines is increased to ensure a sufficient contact area of the spline fitting surface. It is necessary to configure the structure so that the surface pressure applied to it is low and the distributed load is uniform. Outer circumference spline 202 of center support 62
may be formed simultaneously with the transmission case 6 during die casting, or may be formed by machining the center support. In this case, a machining circumferential groove 203 is required as shown in FIG. The common inner race 29 has a front small diameter portion 28.
1 and a rear large diameter section 282 extending from the small diameter section.
A piston 283 consisting of a small diameter portion 284 and a large diameter portion 285 corresponding to the shape of the annular cylinder 223 is fitted into a stepped annular cylinder 223 formed by a common inner race 29 and a piston 283, which constitutes a hydraulic servo _c3 . The outer race of the one-way clutch F _{0 engages with a hub 80 formed integrally with the outer race of the one-way clutch F 0} through a multi-plate clutch C ₃ formed within the front drum 28 . The outer race of the one-way clutch F ₀ is spline-fitted to the hub 80 and connected to the input shaft 7 via a connecting ring 20 spline-fitted to the rear drum 25 . The friend drum 28 is engaged with the transmission case 6 via a brake _B1 , and the outer race of the one-way clutch _F1 is engaged with the transmission case ₆ via a brake B2. One-way clutch F ₀ is formed inside clutch C ₃ , one-way clutch F ₁ is formed inside brake B ₂
is formed inside. A drive shaft 8 spline-fitted into an inner hole 102 in a protrusion 101 formed at the center of the torque converter front cover 13 is inserted into the output shaft 7 of the torque converter 1, and the rear end of the drive shaft 8 The section is supported pivotally by a rear center support 64 of the rear cover, and a gear 1 is mounted at the rear end.
10 is spline-fitted, and the gear 110 is connected to the oil pump cover 6 connected to the outer wall of the rear cover.
1 drives the oil pump 12 inside. At the tip of the output shaft 9 of the gear transmission, there is an output shaft 9,
An output gear 91 is integrally formed, and a pair of tapered roller bearings 92 and 93 connect the output gear 91 to the output gear 91.
It is rotatably supported inside. The reduction mechanism 4 includes a support shaft 41 attached to the reduction gear room 52 in parallel with the axis of the gear transmission 2.
It is supported by the support shaft 41 via a pair of tapered roller bearings 42 and 43, and comprises a reduction gear 44 meshing with the output gear 91, and deceleration is performed between the output gear 91 and the reduction gear 44. There is. The reduction gear 44 meshes with the differential drive large gear 31 and drives the wheel axles 34 and 35 via the differential gear 33. The governor hydraulic pressure generating mechanism 11 mainly includes the governor valve 50, which includes a cylindrical portion 24 projecting forward from the ring gear 242 of the second planetary gear set 24.
A gear 247 is formed on the outer periphery of the vehicle 6, and the gear and the drive gear 501 mesh with each other, and a rotating part 502 connected to the drive gear rotates to supply governor pressure according to the vehicle speed to the hydraulic control device 10. . The clutch, brake, and one-way clutch differential of this gear transmission 2 and the gear ranges and reduction ratios achieved are shown in the following table.

[Table] In the table, 〇 indicates engagement, × indicates disengagement, and △ indicates the state when engine braking is required or when engaged. Note that the present invention is not limited to the above-mentioned embodiments, and various modifications can be made based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the automatic transmission of the present invention, FIG. 2 is a sectional view taken along the line AB, and FIGS. 3 and 4 are enlarged views of the main parts of FIG. 1... Torque converter, 2... Gear transmission, 3
...Differential device, 5...Torque converter case, 6...
Transmission case, 7... Output shaft of torque converter (input shaft of gear transmission), 9... Output shaft of gear transmission, 62... Center support, 63
...Intermediate supporting wall, 91...Output gear, _F2 ...One-way clutch, 200...Inner race, 201...Inner circumference spline, 202...Outer circumference spline.

Claims (1)

[Claims] 1. An intermediate support wall that integrally extends radially inward from the transmission case, a cylindrical center support that integrally extends from the intermediate support wall in the axial direction to support the transmission shaft of the automatic transmission, and a transmission case. a hydraulic servo disposed in a space formed between the syon case, the intermediate support wall, and the center support; a brake that is engaged/disengaged by the hydraulic servo; and a brake disposed between the brake and the center support; 1. An automatic transmission comprising a one-way clutch that allows rotation only in one direction, and a spline engagement between an inner race of the one-way clutch and the center support.