JPH01250643A - Automatic transmission - Google Patents

Abstract

PURPOSE:To make an automatic transmission into miniaturization and lightweightiness by setting up a braking cylinder on the circumference of a flanged part of a retainer member, making it differ in an axial position with a clutch drum, and making the outer diameter of a casing body smaller for the end. CONSTITUTION:A friction plate 71 of a low-and-reverse brake L&R/B is set up on an outer circumferential part of a clutch drum 70. A brake piston 72 of this low-and-reverse brake L&R/B is inserted into a cylinder 74 formed in a case body 50. This cylinder 74 is set up on an outer circumferential part of a flanged part 60b at the same axial position of this flanged part of an output retainer 60. If so, an inner diametral part of the cylinder 74 is situated at the more inner diametral side than the outer diametral part of the clutch drum 70. In brief, the cylinder 74 is made to vary the axial position from the clutch drum 70 in advance, so that is is overlapped in the radial direction. Therefore the outer diameter of the cylinder 74 comes small and thereby the outer diameter of the casing body 50 can be made smaller as well, thus an automatic transmission can be miniaturized as a whole.

Description

[Detailed description of the invention] (b) Industrial application fields The present invention relates to an automatic transmission.

(b) Conventional technology As a conventional automatic transmission, for example,
There is one shown in Publication No. 62. The automatic transmission shown here transmits engine output to the drive wheels by connecting an output shaft and a counter shaft parallel to the output shaft through an output gear and a counter gear, and by connecting the counter shaft to a differential mechanism. It is configured as follows. The output shaft is rotatably supported by an output retainer attached to the casing body, and a clutch drum is rotatably supported on the outer periphery of the cylindrical portion of the output retainer. Furthermore, a cylinder that accommodates a piston for a low and reverse brake is arranged on the outer circumference of the output retainer.

(C) Problems to be Solved by the Invention However, in the conventional automatic transmission as described above, the brake cylinder is arranged on the outer periphery of the clutch drum, so the outer diameter of the cylinder is There is a problem in that the outer diameter of the casing body becomes larger as a result. If the outer diameter of the case body in this portion becomes larger, the diameter of the entire case becomes larger due to the structure of the case molding die, which increases the weight and the size of the entire automatic transmission. The present invention aims to solve such problems.

(d) Means for Solving the Problems The present invention solves the above problems by arranging the brake cylinder not on the outer periphery of the clutch drum but on the outer periphery of the flange-shaped portion of the retainer member.

That is, the automatic transmission according to the present invention includes an annular wall portion (50a) extending radially inward from the inner wall of the casing body (50), a flange portion (60b) El, and a cylindrical portion integral therewith. a retainer member (60) having a portion (60a), a flange-shaped portion of the retainer member is connected to an annular wall portion of the casing body, and a rotating shaft (30) is supported on an inner diameter portion of the retainer member. The present invention is intended for an automatic transmission in which a clutch drum (70) is rotatably supported on the outer diameter of a cylindrical portion of a retainer member, and a friction plate (71) of a multi-disc brake is arranged on the outer periphery of the clutch drum. A cylinder (74) accommodating a brake piston (72) capable of applying a fastening force to the friction plate of the multi-disc brake is arranged on the outer periphery of the flange-shaped portion of the retainer member at the same axial position. It is characterized by the presence of Note that the symbols in parentheses indicate corresponding members in the embodiments described later.

(E) The brake cylinder that accommodates the working brake piston is disposed on the outer periphery of the flange-shaped portion of the retainer member. Therefore, the cylinder has a different axial position from the clutch drum, and the inner diameter portion of the cylinder can be made smaller in diameter than the outer diameter portion of the clutch drum. The outer diameter of the brake piston is also reduced accordingly. Therefore, it is only necessary to secure a space on the outer periphery of the clutch drum in which a friction plate for a multi-disc brake can be arranged, and the diameter of the casing body can be reduced.

(F) Embodiment FIG. 2 shows a skeleton diagram of an automatic transmission. The automatic transmission connected to the engine IO mounted laterally with respect to the vehicle, that is, orthogonal to the longitudinal direction of the vehicle, includes a torque converter 12, a planetary gear transmission mechanism 14, and the like. Torque converter 1 whose rotation from engine 10 is manually powered
2 has a pump impeller 18, a turbine runner 20, a stator 22, and a lock-up clutch 24. The turbine runner 20 is connected to a human-powered shaft 26, and when the lock-up clutch 24 is released, rotational force is transmitted from the pump impeller 18 to the human-powered shaft 26 via fluid, and the lock-up clutch 24 is engaged. A rotational force is mechanically applied to the human-powered shaft 26. The lock-up clutch 24 is operated by the differential pressure between the apply chamber T/A and the release chamber T/R. Note that the torque converter 12 is configured to drive an oil pump 28. The planetary gear transmission mechanism 14 has a first planetary gear set G1 and a second planetary gear set G2, and the first planetary gear set Gl includes a first sun gear St, a first internal gear R1,
The second planetary gear set G2 includes a second sun gear S2, a second internal gear R2, and a second planetary gear set G2. A second pinion carrier PC2 supports a second pinion gear P2 that meshes with both gears S2 and R2 at the same time. The first sun gear St is always connected to the input shaft 26, and the first binion carrier PCI and the second internal gear R2 are always connected to the output shaft 30. The first internal gear R1 is connected to the second pinion carrier PC2 via a forward one-way clutch F10 and a forward clutch F/C arranged in series, and via an overrun clutch O/C arranged in parallel thereto. It is possible. 2nd sun gear S2 is reverse clutch R/C
The second pinion carrier PC2 can be connected to the input shaft 26 via the high clutch H/C. The second sun gear S2 can be fixed to a stationary part by a band brake B/B, and the second sun gear and the nion carrier PC2 are connected to each other via a row one-way clutch L10 and a low and reverse brake L&R/B, which are arranged in parallel with each other. can be fixed to a stationary part. An output gear 32 is provided integrally with the output shaft 30.

A counter gear 34 is provided 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 together with the counter gear 34. The reduction gear 36 meshes with a ring gear 38 of the differential mechanism 16. Drive shafts 40 and 42 protrude left and right from the differential mechanism 16, to which left and right front wheels are connected.

This planetary gear transmission mechanism 14 includes clutches F/C, H/C
, O/C and R/C1 brake B/B and L&R/B,
and each element (Sl, Sl, R1, R2, Pct, and PC2) of the planetary gear sets Gl and G2 by operating the one-way clutches F10 and Llo in various combinations.
The rotation state of the human-powered axis 2 can be changed.
The rotational speed of the output shaft 30 relative to the output shaft 6 can be varied. That is, four forward speeds and one reverse speed can be obtained by operating each clutch, brake, etc. in combination as shown in FIG. Note that in FIG. 3, the O mark indicates that the clutch and brake are engaged, and in the case of a one-way clutch, indicates an engaged state. In addition, 2A, 3R, and 4A in the band brake B/B column are respectively the 2-stage apply chamber 2A, the 3rd speed release chamber 3R, and the 4th speed apply chamber of the hydraulic servo device that operates the band brake B/B. 4A, and the circle mark indicates that hydraulic pressure is being supplied. In addition, αl and G2 are the numbers of teeth of internal gears R1 and R2, respectively, and sun gear S1.
and Sl, and the gear ratio is the ratio of the rotation speed of the human power shaft 26 to the rotation speed of the output shaft 30.

By the operation of the planetary gear transmission mechanism 14 as described above, the rotation of the human power shaft 26 is changed in a predetermined speed and outputted as an output +1!1h30. 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, counter gear 34, and reduction gear 36. Thereby, the left and right front wheels can be driven via the drive shafts 40 and 42. By doing this, forward 4 with overdrive
The speed can be automatically changed.

A part of the power transmission mechanism shown as a skeleton diagram in Figure 2 is shown in Figure 1.
The actual structure is shown in the figure. In FIG. 1, members corresponding to those shown in FIG. 2 are given the same reference numerals. The side cover 52 is attached to the casing body 50 by the bolts 5
It is attached by 4. The left end side of the output shaft 30 in FIG. 1, on which the output gear 32 is integrally provided, is supported by the side cover 52 via a ball bearing 56.

An output retainer 60 (retainer member) is attached to the inside of the casing body 50 with bolts 58. The output retainer 60 has a cylindrical portion 60
a, and a flange-like portion 60b integral therewith. The above-mentioned bolt 58 passes through the flange-like portion 60b and is screwed into the annular wall portion 50a that is integral with the casing body 50. The cylindrical portion 60 of this output retainer 60
A radial needle bearing 62 is provided on the inner diameter portion of a, and supports the right end side of the output shaft 30 in the figure. Additionally, a thrust needle bearing 64 is provided between the output retainer 60 and the side surface of the output gear 32.
is located. A clutch drum 70 that accommodates pistons 66 and 6 of an overrunning clutch O/C and a forward clutch F/C, respectively, is arranged on the outer peripheral side of the output retainer 60.

Further, a friction plate 71 of a low and reverse brake L&R/B is arranged on the outer circumference of the clutch drum 70. A brake piston 72 of the low and reverse brake L&R/B is inserted into a cylinder 74 formed in the case body 50.

The cylinder 74 is disposed at the same axial position as the flange-like portion 60b of the output retainer 60 and on the outer peripheral portion thereof. As a result, the inner diameter portion of the cylinder 74 is positioned closer to the inner diameter side than the outer diameter portion of the clutch drum 70. That is, the cylinder 74 is located at a different axial position from the clutch drum 70, and they overlap in the radial direction. As a result, the outer diameter of the cylinder 74 becomes smaller, and the outer diameter of the casing body 50 can be reduced accordingly. By reducing the outer diameter of the casing body 50, the entire automatic transmission can be downsized and its weight can also be reduced.

(G) As described in detail, according to the present invention, the brake cylinder is disposed on the outer periphery of the flange-shaped portion of the retainer member,
Since the axial position is different from that of the clutch drum, the cylinder can be placed closer to the inner diameter, and the outer diameter of the casing body can be reduced accordingly, making automatic transmissions easier to use. It can be made smaller and lighter.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2 is a schematic diagram of an automatic transmission, and FIG. 3 is a diagram showing a combination of elements that operate at each gear stage. 30... Output shaft, 32... Output gear, 34... Counter gear, 50... Casing body, 50a...
Annular wall portion, 52... Side cover, 56... Ball bearing, 60... Output retainer, 60a
...Cylindrical part, 60b...Flanged part, 62...
・Radial needle bearing, 64... Thrust needle bearing, 70... Clutch drum, 71.
...6! Plate, 72...Brake piston, 74
···Cylinder.

Claims (1)

[Scope of Claims] The retainer member has an annular wall portion integrally projecting inward from the inner wall of the casing body, and a retainer member including a flange-like portion and a cylindrical portion integral therewith. The flange-shaped part is connected to the annular wall part of the casing body, a rotating shaft is supported on the inner diameter part of the retainer member, a clutch drum is rotatably supported on the outer diameter part of the cylindrical part of the retainer member, and the clutch drum In an automatic transmission in which a friction plate of a multi-disc brake is disposed on the outer periphery of the multi-disc brake, a cylinder is provided in the casing that accommodates a brake piston capable of applying a fastening force to the friction plate of the multi-disc brake. An automatic transmission characterized in that the flange-shaped portion of the retainer member is disposed at the same axial position and on the outer periphery of the retainer member.