JP3347345B2 - Automatic transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission for a motor vehicle, and more particularly to the arrangement and lubrication of a row one-way clutch.

[0002]

2. Description of the Related Art Conventionally, as an automatic transmission, for example, an "Automatic transaxle maintenance manual (RN4F02A type)
RL4F02A) (published by Nissan Motor Co., Ltd. in February 1984) and the NISSAN Full-Range Electronically Controlled Automatic Transmission E-AT Maintenance Manual (RE4R01A) (March 1987 Nissan Motor) Issuance).

[0003] The former has a structure in which a row one-way clutch is arranged on the outer periphery of a carrier of a front planetary gear.

[0004] The latter has a structure in which a row one-way clutch is disposed at a position rearward of a forward clutch drum.

[0005]

However, in the former automatic transmission, since the low one-way clutch is disposed on the outer periphery of the carrier of the front planetary gear, even if the low reverse brake is formed into a band, it may be out of the case. The diameter is determined by the row one-way clutch, and miniaturization is difficult. In addition, when trying to make the gear ratio cross, the outer diameter of the carrier also increases the diameter of the low one-way clutch, and the low one-way clutch itself increases in diameter despite the reduced load torque.

On the other hand, in the latter automatic transmission, the outer diameter can be reduced because the row one-way clutch is disposed behind the forward clutch drum.
It is difficult to shorten the overall length.

The present invention has been made in view of the above-mentioned problems, and it is possible to reduce the outer diameter of the row one-way clutch without being affected by the gear ratio and to prevent the overall length from becoming longer. A first object is to make the automatic transmission compact, and a second object is to smoothly lubricate the row one-way clutch.

[0008]

According to the present invention, the first object is achieved by disposing the row one way clutch on the outer periphery of the piston of the drum, and a notch is provided on the outer periphery of the inner race of the row one way clutch. The second object is achieved by providing a communication hole communicating the notch and the inner periphery.

That is, in the automatic transmission according to the present invention, the planetary gear provided on the outer periphery of the input shaft, the drum provided on the outer periphery of the planetary gear, and the internal gear of the planetary gear are fixed to the drum. A clutch for switching to a relative rotatable state, a piston provided inside the drum for engaging the clutch, and interposed between the drum and a transmission case, and an outer race fixed to the transmission case side On the other hand, the inner race has a low one-way clutch mounted on the outer periphery of the piston sliding portion of the drum.

According to a second aspect of the present invention, there is provided an automatic transmission, wherein a plurality of notches are provided on an outer periphery of an inner race of the low one-way clutch, and the notches are communicated to an inner peripheral side by a communication hole. A lubrication circuit was formed in the lubrication circuit of the member on the transmission case side adjacent to the clutch, the lubrication hole having the open end facing the notch.

[0011]

Since the inner race of the row one-way clutch is mounted on the outer periphery of the sliding portion of the piston of the drum, the axial dimension can be reduced by the amount of overlap between the two. Also, even if the outer diameter of the planetary gear is increased by crossing the gear ratio in the planetary gear, etc., the low one-way clutch is not arranged in the radial direction. The dimensions do not increase.

In the automatic transmission according to the second aspect, when the row one-way clutch idles, lubricating oil supplied from the open end of the lubrication hole is stored in the notch, from which the lubricating oil is transmitted through the communication hole to the row one. Supplied inside the way clutch. Therefore, high lubrication performance is obtained.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a schematic diagram showing a main part of the automatic transmission according to the embodiment.

In FIG. 1, reference numeral 1 denotes an input shaft. The input shaft 1 receives torque from an engine output shaft (not shown) via a torque converter. The torque of the input shaft 1 is transmitted by a main transmission mechanism MGT having a front planetary gear 2, a rear planetary gear 3, and the like. After the speed is changed, the power is transmitted from the output gear 4 to an adjacent sub-transmission mechanism (not shown).

The front planetary gear 2 includes a sun gear 2a connected to the input shaft 1 by a spline as shown, an internal gear 2b provided around the outside of the sun gear 2a, and an internal gear with the sun gear 2a. A carrier 2d for supporting a pinion gear 2c meshing with the gear 2b at the same time is provided. The carrier 2d is connected to an outer peripheral surface of an output shaft 4a having the output gear 4 by a spline. A low clutch 5 is provided on the outer periphery of the internal gear 2b, and the internal gear 2b can be switched between a fixed state and a relatively rotatable state with respect to the low clutch drum 5a. I have.

The rear planetary gear 3 includes a shaft 1 a provided on the outer periphery of the input shaft 1.
A sun gear 3a connected to the sun gear 3a, an internal gear 3b provided on the outer periphery of the sun gear 3a and connected to the carrier 2d by a spline, and meshes with the sun gear 3a and the internal gear 3b at the same time. A carrier 3d that supports the pinion gear 3c and is connected to the low clutch drum 5a is provided.

That is, each of the planetary gears 2 and 3 fixes or drives three elements of each of the sun gears 2a and 3a, the internal gears 2b and 3b, and the carriers 2d and 3d, respectively, so that the output relative to the rotation speed of the input shaft 1 is obtained. The rotation speed of the shaft 4a is changed.

The output shaft 4a is
The transmission case 6 is rotatably supported. The bearing structure is such that an output shaft 4a is fixed to a fixing member 61 fixed to the transmission case 6 with bolts 6a.
Are supported by a radial needle bearing 4b and a cylindrical roller bearing 4c, and both side surfaces of the output gear 4 are thrust needle bearings 4b.
d, 4d.

A piston 5b for engaging and disengaging the low clutch 5 is slidably housed in the low clutch drum 5a. The low clutch drum 5a is connected to the piston 5b
The sliding portion is formed with a small diameter to form a step 5c. The piston 5b is driven by hydraulic pressure supplied from a hydraulic circuit (lubricating circuit) 61a formed on the fixed member 61.

A low one-way clutch 7 is provided between the step 5c and the transmission case 6. That is, in the low one-way clutch 7, the inner race 7a is attached to the stepped portion 5c in a fitted state, and the outer race 7b is fixed to the transmission case 6 so as to face the inner race 7a. Note that the fixing structure of the outer race 7b is a structure in which the fixing member 61 is sandwiched between a step 6b formed in the transmission case 6 and the fixing member 61.

Further, on the outer periphery of the inner race 7a,
At the time of material forging, a plurality of notches 7c are formed. The notch 7c communicates with the inner peripheral side through a communication hole 7d. A lubricating oil catch groove 5 is formed at an end of the step 5c of the low clutch drum 5a at a position facing the notch 7c.

The fixing member 61 includes a hydraulic circuit 6.
A lubrication hole 61b having an open end is bored toward the notch 7c in communication with 1a.

In the automatic transmission of the present embodiment configured as described above, the lubricating oil supplied from the lubricating hole 61b is stored in the notch 7c and the lubricating oil catch groove 5d when the row one-way clutch 7 idles. Then, it is supplied to the inside of the row one-way clutch 7 through the communication hole 7d. Therefore, high lubrication performance is obtained. In particular,
In the present embodiment, a lubricating oil catch groove 5d is formed in the low clutch drum 5a at a position facing the notch 7c, and lubricating oil is easily accumulated in this portion, so that lubricating oil is smoothly supplied.

In this embodiment, the low one-way clutch 7 is provided at an outer peripheral position of a portion where the piston 5b of the low clutch drum 5a slides. Therefore, the axial dimension can be reduced, and the outer diameter can be reduced irrespective of the gear ratio as compared with the one arranged on the outer periphery of the front planetary gear 2. Therefore, the overall length and outer diameter of the automatic transmission itself can be reduced, and the automatic transmission can be made compact.

In particular, in this embodiment, the stepped portion 5c is formed on the low clutch drum 5a, and this portion is formed to have a smaller diameter than the others, so that the outside diameter of the automatic transmission is further reduced to achieve compactness. I have.

Although the embodiment of the present invention has been described with reference to the drawings, the specific configuration is not limited to this embodiment.

[0027]

As described above, in the automatic transmission according to the present invention, since the inner race of the row one-way clutch is mounted on the outer periphery of the piston sliding portion of the drum, the row one-way clutch is provided. The size in the axial direction can be reduced as compared with the case where it is provided in the axial direction of the drum, and in comparison with the case where it is provided on the outer periphery of the planetary gear, the outer diameter can be reduced regardless of the gear ratio. The effect that the transmission can be made compact can be obtained.

Further, in the automatic transmission according to the present invention, in addition to the above configuration, a plurality of notches are provided on the outer periphery of the inner race of the row one-way clutch, and the notches are formed on the inner peripheral side by the communication holes. The lubrication circuit of the transmission case side member adjacent to the low one-way clutch has a lubrication hole with the open end facing the notch, so that lubricating oil easily accumulates in the notch and is smooth inside. High lubricity is obtained by supplying lubricating oil to

[Brief description of the drawings]

FIG. 1 is a partial sectional view showing a main part of an automatic transmission according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Input gear 2 Front planetary gear 2b Internal gear 5 Low clutch 5a Low clutch drum 5b Piston 6 Transmission case 61a Hydraulic circuit (lubrication circuit) 61b Lubrication hole 7 Low one-way clutch 7a Inner race 7b Outer race 7c Notch 7d Communication hole

Claims (2)

(57) [Claims] 1. A planetary gear provided on an outer periphery of an input shaft, a drum provided on an outer periphery of the planetary gear, and an internal gear of the planetary gear in a fixed state and a relatively rotatable state with respect to the drum. A switching clutch, a piston provided inside the drum and engaging the clutch, interposed between the drum and a transmission case, the outer race is fixed to the transmission case side, while the inner race is An automatic transmission, comprising: a low one-way clutch mounted on an outer periphery of a piston sliding portion. 2. The inner race of the row one-way clutch is provided with a plurality of cutouts on the outer periphery, the cutouts being communicated to the inner circumference through communication holes, and a transmission case side adjacent to the row one-way clutch. 2. The automatic transmission according to claim 1, wherein a lubrication hole having an open end facing the notch is formed in a lubrication circuit of the member.