JPH0765649B2 - Automatic transaxle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an automatic transaxle.

(B) Conventional technology As a conventional automatic transaxle, "Automatic transaxle RN4F02A type, RL4F02A type, 19
84 "Maintenance Manual" (issued by Nissan Motor Co., Ltd.) The automatic transaxle shown therein connects the output shaft of the automatic transmission mechanism unit and the counter shaft parallel thereto with the output gear and the counter gear, and connects the counter shaft with the differential mechanism,
It is configured to transmit the output of the engine to the drive wheels. The output shaft is supported by bearings arranged at both ends of the output gear. A bearing on the side opposite to the automatic transmission mechanism is supported by a side cover attached to the casing body, and the other bearing is attached to an output retainer attached to the casing body. A clutch drum of an automatic transmission mechanism is supported on the outer diameter of the output retainer, and an oil passage for supplying hydraulic oil to the clutch drum extends from the casing body to the clutch drum through the output retainer. Therefore, the output retainer needs to have a predetermined radial thickness in order to provide a portion parallel to the axial direction of the oil passage. The other bearing is arranged inside the portion of the output retainer where the oil passage is provided.

(C) Problems to be Solved by the Invention However, in the conventional automatic transaxle as described above, since the oil passage and the bearing of the output retainer are arranged in a state of overlapping in the radial direction, the output retainer is disposed. And the diameter of the clutch drum arranged on the outer periphery of the output retainer also increases. Therefore, in order to obtain the required clutch capacity, it is necessary to increase the outer diameter of the clutch drum to increase the outer diameter of the entire automatic transaxle. As the size of the automatic transaxle increases, the performance of the vehicle is reduced, the weight also increases, and the price also increases. Moreover, since the diameter of the clutch drum is large, hydraulic pressure is generated by centrifugal force, and countermeasures against this are required.

The present invention aims to solve such problems.

(D) Means for Solving the Problem The present invention provides an output gear of an automatic transmission mechanism and a counter shaft parallel to the output shaft, which are provided so as to rotate integrally with the output shaft and the counter shaft, respectively. Also, in the automatic transaxle connected by the counter gear, the casing body of the automatic transaxle has an annular wall portion protruding from the inner wall of the casing body to the inner diameter side at the boundary between the automatic transmission mechanism arrangement side and the output gear arrangement side. A substantially cylindrical output retainer with a flange is attached to the surface of this wall on the automatic transmission mechanism side, with the flange portion in close contact, and the automatic transmission mechanism portion of the output retainer is installed. The clutch drum of the automatic transmission mechanism is supported on the outer periphery of the substantially cylindrical portion on the side of the casing. An oil passage for supplying hydraulic oil from the wall portion of the main body is provided through the flange portion and the substantially cylindrical portion of the output retainer, and the axial position of the substantially cylindrical portion of the output retainer is the wall of the casing. One bearing that supports the output shaft is provided in the inner diameter portion of the portion that coincides with the portion,
The other bearing that supports the output shaft is provided at a portion where the axial position of the inner diameter portion of the output retainer is different from that of the one bearing arrangement portion and has substantially the same diameter, and supplies the hydraulic oil. The portion of the oil passage that is provided in the substantially cylindrical portion in parallel with the axial direction of the oil passage is located in the middle of both of the bearings and is disposed in a portion having substantially the same diameter as these.

(E) Action One bearing is located at a position where the axial direction of the bearing matches the wall of the casing of the output retainer, and the other bearing is located at the substantially cylindrical portion of the output retainer. It is possible to firmly support the output shaft, which receives a load in the direction perpendicular to the shaft center with the transfer of the power, by the two bearings on the annular wall portion of the inner wall of the casing body. In this case, since the two bearings support the portions of the output shaft having substantially the same diameter, the effective diameter of the output shaft can be formed to the minimum required point.
When the bearing diameters of the bearings are different, since the small diameter bearing is used as the effective diameter of the output shaft, the diameter of the large diameter bearing part becomes unnecessarily large, and the weight of the output shaft becomes heavier. Also, since both bearings are supported by the output retainer that is attached to the annular wall of the casing, the axial length of the output shaft can be shortened compared to when it is supported on the opposite side of the output gear. This also leads to weight reduction of the output shaft.

Further, the oil passage for supplying the hydraulic pressure to the clutch drum, which is formed in parallel to the axial direction of the output retainer, is formed between both bearings and at substantially the same radial position as the bearings, and therefore the output passage is correspondingly formed. The diameter of the retainer can be reduced, the diameter of the clutch drum can be reduced accordingly, and the automatic transmission mechanism can be downsized.

(F) Example (First Example) FIG. 2 shows a frame diagram of an automatic transaxle. The automatic transmission mechanism portion of an automatic transaxle connected to an engine 10 mounted laterally with respect to a vehicle, that is, orthogonal to the vehicle front-rear direction, includes a torque converter 12, a planetary gear transmission mechanism 14, and the like. The torque converter 12 to which the rotation from the engine 10 is input has a pump impeller 18, a turbine runner 20, and a stator 22.
And a lockup clutch 24. The turbine runner 20 is connected to the input shaft 26, and when the lockup clutch 24 is released, the rotational force is transmitted from the pump impeller 18 to the input shaft 26 via fluid, and the lockup clutch 24 is engaged. Then, the rotational force is mechanically input to the input shaft 26. The lockup clutch 24 operates by the differential pressure between the apply chamber T / A and the release chamber T / R. In addition,
The torque converter 12 is configured to drive the oil pump 28. The planetary gear speed change mechanism 14 is the first planetary gear set.
G ₁ and has the second has a planetary gear set G _2, the first planetary gear set
G ₁ is the first sun gear S ₁ , the first internal gear R ₁ ,
A first pinion carrier PC ₁ supporting a first pinion gear P ₁ that meshes with both gears S ₁ and R ₁ at the same time, and a second planetary gear set G ₂ includes a second sun gear S ₂ and a second sun gear S ₂ . Two
A second pinion carrier that supports an internal gear R ₂ and a second pinion gear P ₂ that meshes with both gears S ₂ and R ₂ at the same time.
It consists of PC ₂ and. The first sun gear S ₁ has an input shaft 26
Always connected to the 1st pinion carrier PC ₁
The second internal gear R ₂ is always connected to the output shaft 30. The first internal gear R ₁ is connected to the second pinion carrier PC via the forward one-way clutch F / O and the forward clutch F / C arranged in series, and the overrun clutch O / C arranged in parallel with these. Can be connected with ₂ . The second sun gear S ₂ is a reverse clutch R /
It can be connected to the input shaft 26 via C, and the second pinion carrier PC ₂ can be connected to the input shaft 26 via the high clutch H / C. The second sun gear S ₂ can be fixed to the stationary part by a band brake B / B, and the second pinion carrier PC ₂ is a low one-way clutch L / O and a low and reverse brake L & R / B arranged in parallel with each other. It can be fixed to the stationary part via and. An output gear 32 is provided integrally with the output shaft 30. A counter gear 34 is provided so as to mesh with the output gear 32, and a reduction gear 36 is connected to the counter gear 34 via a counter shaft 35 so as to rotate integrally. Reduction gear
The 36 engages with the ring gear 38 of the differential mechanism 16. The drive shafts 40 and 42 project left and right from the differential mechanism 16, and the left and right front wheels are connected thereto.

This planetary gear speed change mechanism 14 operates clutches F / C, H / C, O / C and R / C, brakes B / B and L & R / B, and one-way clutch F / O and L / O in various combinations. Each element of the planetary gear set G ₁ and G ₂ (S ₁ , S ₂ , R ₁ , R ₂ , PC ₁
And it can change the rotating state of the PC _2), whereby it is possible to change various rotational speed of the output shaft 30 to the input shaft 26. That is, by operating each clutch, brake, etc. in a combination as shown in FIG. 3, it is possible to obtain the fourth forward speed and the first reverse speed. In addition, in FIG.
The mark indicates that the clutch and brake are engaged,
Also, in the case of a one-way clutch, the engaged state is shown. In addition, 2A, 3R and 4A are shown in the band brake B / B column respectively for the second speed apply chamber 2A, the third speed release chamber 3R and the fourth speed apply of the hydraulic servo device that operates the band brake B / B. The chamber 4A is shown, and the mark ○ indicates that hydraulic pressure is being supplied. Further, α ₁ and α ₂ are the ratios of the number of teeth of the sun gears S ₁ and S _{2 to} the number of teeth of the internal gears R ₁ and R ₂ , respectively, and the gear ratio is the ratio of the input shaft 26 to the rotation speed of the output shaft 30. It is the ratio of the number of rotations.

By the operation of the planetary gear speed change mechanism 14 as described above, the input shaft
The rotation of 26 is subjected to a predetermined speed change and is output to the output shaft 30. The rotational force of the output shaft 30 is transmitted to the ring gear 38 of the differential mechanism 16 via the output gear 32, the counter gear 34, and the reduction gear 36. As a result, the left and right front wheels can be driven via the drive shafts 40 and 42. By doing so, it is possible to perform automatic forward four-speed shift with overdrive.

A part of the power transmission mechanism shown as a frame diagram in FIG.
The figure shows the actual structure. In FIG. 1, members corresponding to those shown in FIG. 2 are designated by the same reference numerals. The casing body 50 has an annular wall portion 52 on the output side of the automatic transmission mechanism, that is, on the left end side in FIG. An output retainer 54 is attached to this wall portion 52. The output retainer 54 has a shape in which a flange portion 54b is provided on the outer circumference of a substantially cylindrical portion 54a. The output retainer 54 is illustrated in a state in which the outer diameter portion of the substantially cylindrical portion 54a is fitted to the inner diameter portion of the wall portion 52 and the left end surface of the flange portion 54b is closely attached to the right end surface of the wall portion 52 in the drawing. Attached by no bolts. The inner diameter of both ends of the substantially cylindrical portion 54a is larger than the diameter of the central portion, and the bearings 56 and 58 are arranged in this portion, respectively. The bearing 58 directly supports the output shaft 30, and also the output shaft
The shaft portion of the output gear 32, which is connected to rotate integrally with the shaft 30, is supported by the bearing 56. The bearing 56 is arranged at the same axial position as the wall portion 52. An overrunning clutch O / C and a forward clutch F / C are provided on the outer periphery of the substantially cylindrical portion 54a of the output retainer 54.
The clutch drum 60 of is rotatably supported. In order to supply the hydraulic oil to the clutch drum 60, the output retainer 54 is provided with a radial hole 62, an axial hole 64, and a radial hole 66, and the radial hole 66 includes the wall portion 52.
Is connected to an oil passage 68 provided in the. As a result, working pressure can be supplied to the clutch drum 60 from the oil passage 68 through the radial hole 66, the axial hole 64, and the radial hole 62. Incidentally, the radial hole 66, the axial hole 64 and the radial hole 62.
Is an oil passage for supplying a hydraulic pressure to an oil chamber that applies a hydraulic pressure to the piston 70 for the forward clutch F / C in the clutch drum 60, but the piston of the overrunning clutch O / C is shown in a cross section not shown. An oil passage for supplying hydraulic pressure to 72 is also provided. Further, as shown in the lower cross section in FIG. 1, an oil passage 74 for supplying lubricating oil is also provided. The axial oil passages provided in the output retainer 54, such as the axial holes 64, are arranged in portions having substantially the same diameter without overlapping the bearing 56 and the bearing 58 in the radial direction.

As described above, the bearing 56 and the bearing 58 and the axial hole 64 do not overlap each other in the radial direction and are arranged in a portion having substantially the same diameter. Therefore, the substantially cylindrical portion 54a of the output retainer 54 is the same as the bearing 56 and the bearing 56. As long as it has a wall thickness necessary to support the bearing 58,
The outer diameter can be reduced. Therefore, the inner diameter portion of the clutch drum 60 can be reduced, and accordingly, the necessary pressure receiving area can be secured without increasing the outer diameters of the piston 70 and the piston 72. The diameter also becomes smaller. As a result, the outer diameter of the entire automatic transmission mechanism can be reduced, and accordingly, the outer diameter of the casing body 50 can be reduced. This reduces the weight and also the price. The hydraulic pressure generated by the centrifugal force acting on the oil inside the clutch drum 60 is also reduced. In addition, in this first embodiment,
The bearing 56 is arranged at a position substantially on the inner diameter side of the wall portion 52, and compared with the case where the bearing 56 is arranged at the position on the left side of the output gear 32 in the figure, the entire axial direction is about the axial dimension of the bearing 56. The size can be shortened. Further, since the bearing 56 and the bearing 58 are both supported by the output retainer 54 and need not be supported by other parts, the side cover 76 that seals the open side of the casing body 50 is hermetically sealed so that oil does not leak. Since it does not need strength, rigidity, etc., it can be made of a press as shown in FIG. 1. This reduces the weight and reduces the price.

(Second Embodiment) (G) Effect of the Invention As described above, according to the present invention, one bearing is located at a position where the axial position of the bearing of the output retainer coincides with that of the output retainer, and the other bearing is located at the output. The output shaft, which is arranged at a substantially cylindrical portion of the retainer and receives a load in the direction perpendicular to the shaft center when the power is transmitted and received between the counter shaft and the annular wall portion of the inner wall of the casing body,
It can be firmly supported by two bearings,
In this case, since the two bearings support the portions of the output shaft having substantially the same diameter, the effective diameter of the output shaft can be formed to the minimum required amount, and both the bearings are formed on the annular wall portion of the casing. Since it is supported by the output retainer to be installed, the length of the output shaft in the axial direction can be shortened. As a result, the required strength of the output shaft can be maintained and the weight can be reduced, while the axial direction of the output retainer can be reduced. Since the oil passage that supplies the hydraulic pressure to the clutch drum that is formed in parallel with is formed between both bearings and at substantially the same radial position as the bearings, the diameter of the output retainer can be reduced accordingly. Accordingly, the diameter of the clutch drum is also reduced, and the automatic transmission mechanism can be downsized.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention, FIG. 2 is a skeleton diagram of an automatic transaxle, and FIG. 3 is a diagram showing a combination of elements that act at each shift speed. 30 …… Output shaft, 32 …… Output gear, 34 …… Counter gear,
35 …… Counter shaft, 50 …… Casing body, 52 …… Wall, 54 …… Output retainer, 56 …… Bearing,
58 …… Bearing, 60 …… Clutch drum, 64 …… Axial hole.

Claims (1)

[Claims] 1. An automatic transmission in which an output shaft of an automatic transmission mechanism and a counter shaft parallel to the output shaft are connected by an output gear and a counter gear provided so as to rotate integrally with the output shaft and the counter shaft, respectively. In the transaxle, the casing body of the automatic transaxle has an annular wall portion projecting from the inner wall of the casing body to the inner diameter side at the boundary between the automatic transmission mechanism arrangement side and the output gear arrangement side. A substantially cylindrical output retainer with a flange is attached to the surface on the automatic transmission mechanism side, with the flange part in close contact with the outer periphery of the approximately cylindrical portion on the automatic transmission mechanism side of the output retainer. Is supported by the clutch drum of the automatic transmission mechanism, and hydraulic oil is supplied to the clutch drum from the wall of the casing body. Is provided through the inside of the flange part and the substantially cylindrical part of the output retainer, and the axial position of the substantially cylindrical part of the output retainer is in the inner diameter part of the part where it coincides with the wall part of the casing. One bearing that supports the output shaft is provided, and the other bearing that supports the output shaft is a portion in which the axial position of the inner diameter portion of the output retainer is different from that of the one bearing arrangement portion and is almost the same. A portion of the oil passage for supplying the working oil, which is provided in a portion having the same diameter and provided in a substantially cylindrical portion in parallel with the axial direction thereof, is located in the middle of both the bearings and is substantially the same as these. An automatic transaxle characterized by being located in the diameter section.