JPH0571600A - Automatic transmission - Google Patents

Abstract

PURPOSE:To make a transmission light and small at a low cost by arranging A and D gears on a main shaft, B and E gears on a middle shaft and a C gear on an annular shape drive shaft and exerting A and C clutchs on the main shaft and a B clutch and a one way clutch on the drive shaft. CONSTITUTION:An A gear 7 is mounted capable of idling on an annular shape shaft 8 and a C gear 14 installed on a concentric shaft 13 with an annular drive shaft 12 acts through B clutch 15 via a B gear 11 installed on an annular middle shaft 10 idling on a pin 9. A D gear 16 is mounted capable of idling on an annular shaft 25. An E gear 18 is mounted on the middle shaft 10 in a same body and a F gear 19 is mounted capable of idling on the drive shaft 12 through an annular shaft 20 and acts on the drive shaft 12 through an one way clutch 21. As an A gear 16, C gear 14 and F gear 19 can operate at the respective two speeds, a speed change of forward 8 steps can be obtained regardless of a small number of gears six pieces in total.

Description

Detailed Description of the Invention [Industrial applications]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an 8-speed automatic transmission for a front two-wheel (or rear two-wheel) drive vehicle with an engine placed horizontally.

[Prior Art]

When a three-axis type automatic transmission is applied to a two-wheel drive vehicle with a horizontal engine, there is a problem that it is difficult to obtain a two-speed shift suitable for engine braking.

[Problems to be Solved by the Invention]

According to the present invention, there are provided two transmission gears each having a different diameter on three main shafts, a center shaft and a drive shaft, which are provided in parallel with each other.
The total number of gears used and the number of clutches (number of clutches ( (Including one-way clutches) to reduce the size, weight and cost.

[Means for Solving the Problems]

The present invention will be described below with reference to the drawings.
1 is a plan sectional view showing an embodiment of an automatic transmission according to the present invention, and FIG. 2 is a shift control circuit diagram thereof. The turbine (4) of the torque converter (3) directly connected to the output shaft (2) of the engine (1) directly drives the main shaft (5) on the right side, and the A gear (7) is driven via the A clutch (6).
(Gear number 17) is provided on the annular shaft (8) so as to be idle, and the B gear (11 provided on the same body on the annular middle shaft (10) that is idle on the pin (9). ) (The number of teeth 43), the C gear (14) (the number of teeth 65) mounted on the annular shaft (13) concentric with the annular drive shaft (12) passes through the B clutch (15). Operate. D gear (16) (number of teeth 1
7) is also rotatably mounted on the annular shaft (25), and C
It operates via the clutch (17). E gear (18)
The (number of teeth 23) is provided in the same body on the center shaft (10), and the F gear (19) (the number of teeth 49) is provided on the drive shaft (12) so as to be freely rotatable via the annular shaft (20). , Via the one-way clutch (21) to the drive shaft (12). The main shaft (5), the center shaft (10) and the drive shaft (12) are all provided in parallel to each other and are compactly housed in the case (22). The distance between the drive shaft (12) and the center shaft (10) is 1.8, which is the distance between the center shaft (10) and the main shaft (5).
These three axes are not necessarily on the same plane, but they can be miniaturized by arranging them, and the degree of freedom in design is improved. A clutch (6), C clutch (1
7) to the left of the oil pump (23) on the central shaft (2
Since it is driven by 4), the C gear (14) and the F gear (1
The fact that 9) can be arranged close to the torque converter (3) has the advantage that the left propeller shaft (not shown) can be taken longer. A switching device (27) that operates via a drum (26) is provided on the right side of the drive shaft (12), and a large sun gear (28) (having 24 teeth) is provided with a Ravigneaux planetary gear via a long pinion (29). Equipment ring gear (30)
When the number of teeth (66) is fixed by the D clutch (31), the forward rotation reduction action is performed at the reduction ratio of 3,750 (3).
2) to the annular input shaft (33). The short pinion (34) on the carrier (32) is the small sun gear (35).
It is obtained via the gear (20) through the carrier (32) of the reverse deceleration action at the speed reduction ratio of 4,500 when retreating.
The input shaft (33) is rotated by the ring gear (37) and the double pinion (38) (39) of the differential device (36), the carrier (40) side through the left extraction shaft (41), and the left wheel (Fig. The sun gear (42) side is interlocked with a right wheel (not shown) via a right extraction shaft (43). E gear (18) with a large load is B gear (11)
The tooth pitch is larger, and the B clutch (15) has a larger diameter than the A clutch (6). The E clutch (44) is used when the drive shaft (12) and the input shaft (33) are directly connected and is installed in the drum (26).

[Action]

The output of the engine (1) performs a known predetermined operation in the torque converter (3) to rotate the main shaft (5). In the first speed, the C clutch (17) does not operate, only the A clutch (6) operates, and the rotation of the main shaft (5) causes the A gear (7), B gear (11), E gear (18) and E gear (18) to rotate. F gear (1
9), the one-way clutch (21) is actuated to drive the drive shaft (12), and the switching device (27) is actuated to the right to rotate the large sun gear (28). The carrier (32), which is linked with the input shaft (33) and is linked with the input shaft (36), is stopped. A clutch (6) and D
When the rotating ring gear (30) is fixed to the case (22) and stopped by the gradual operation of the clutch (31), the input shaft (33) starts to rotate in the forward direction, and on the drive shaft (12) in this case. Has a reduction ratio of 5,387, so the total reduction ratio on the input shaft (33) is 20,201 (reduction ratio x
3,750 times). In the second speed, the A gear (7) and the B gear (1
1) B clutch (15) via C gear (14)
The speed reduction ratio on the drive shaft (12) is 3,823, and the total speed reduction ratio of the input shaft (33) is 14,336. In the 3rd speed, only C clutch (17) is activated, and D
The reduction ratio of the drive shaft (12) is 2,882 by the operation of the one-way clutch (21) through the gear (16), the E gear (18) and the F gear (19), and the input shaft (3
The total reduction ratio of 3) is 10,807. In the fourth speed, the B clutch (15) is actuated on the drive shaft (12) via the D gear (16), the E gear (18), the B gear (11) and the C gear (14). A reduction ratio of 2,043 is obtained, so that the total reduction ratio is 7,661. In the fifth speed, only the A clutch (6) is operated, and the B gear (11) and E gear (1
8) The one-way clutch (21) is operated via the F gear (19) and the reduction ratio of 5, 3 is set on the drive shaft (12).
87 is obtained, the input shaft (33) is directly connected and rotated by the direct connection operation of the E clutch (44), and the total reduction ratio of the input shaft (33) is also 5,387. The sixth speed is the same as the second speed, with the operation of only the A clutch (6), through the A gear (7), the B gear (11) and the C gear (14),
Activates B clutch (15) and then E clutch (44)
Is operated to directly and interlock the input shaft (33) and the drive shaft (12), and the total reduction ratio becomes 3,823. 7th speed is 3rd
Similar to the speed, only the C clutch (17) is operated, and the one-way clutch (21) is operated via the D gear (16), E gear (18) and F gear (19) to drive during direct connection. In the shaft (12) and the input shaft (33), the total reduction ratio 2,
882 is obtained. The 8th speed is an input shaft (33) that is directly connected to obtain the same total reduction ratio 2,043 as the 4th speed.
Obtained above. At the time of retreat (the speed reduction ratio is 4,500 times), the first or second speed operation is moved to the left when the switching device (27) is stopped, and the total speed reduction ratio is set at the input shaft (33). 24,241 or 17,203 can be obtained.
These are always D when directly connected by the E clutch (44) operation.
Release the operation of the clutch (31) and set the ring gear (3
Since 0) idles integrally with the carrier (32), there is no gear loss due to the reverse rotation and reduction gear (45), and there is an advantage that noise is not generated. Second when traveling in economy,
The fact that the vehicle can be started at the third, fourth, and fifth speeds can be automatically performed as is known by control by a known computer or the like (see FIG. 2). The operation of the five clutches (6) (15) (17) (31) (44) A, B, C, D and E is performed by the known control in which pressurization by the pump (23) is shown in FIG. Controlled by a circuit, each oil passage (46) (47)
(48) (49) (50) Each of these clutches is caused to perform a predetermined operation individually, and each clutch has a cylinder (51), a piston (52), a spring (53), and a plurality of springs (53). A plate clutch (54) is installed as is known. Next, the first feature of the automatic transmission of the present invention is as follows.
The operation of 8th speed is that each clutch is always loosened before the next operation, so that it has good responsiveness at the next speed stage. That is, in the first speed from the A clutch (6), the A clutch (6) and the D clutch (31) are open and waiting before the operation in the second speed (hereinafter abbreviated as waiting). , B
The clutch (15) opens, the C clutch (17) opens in the 3rd speed, the B clutch (15) opens in the 4th speed, and the A clutch (6) and the 6th speed in the 5th speed. Both the E clutch (44) is waiting, and in the 6th speed, the B clutch (1
5) opens again, the C clutch (17) opens in the 7th speed, and the B clutch (15) opens in the 8th speed.
When the vehicle is moving backward, the switching device (24) is operated by a known method (not shown), and then [the A clutch (6) is used when the vehicle is moving in the second speed].
D-Clutch (31) opens. These are the springs (5
This is because it is loosened and opened by 3) and stands by for the next speed stage, which enables smooth continuous gear shifting regardless of which speed stage. The paragraph ratios of the total speed reduction ratios of the respective speed stages in this embodiment are almost the same, and the ideal torque distribution is constituted. When starting in first speed during economy running, skipping second speed and then shifting to third speed, similarly, when starting in second speed, skipping third speed and then shifting to fourth speed, which is less Automatic shifting is performed according to the number of shift changes. The eighth speed is also called the second overdrive and is more advantageous for economical traveling at high speeds. After all, the fact that each speed stage up to the 8th speed can be freely selected according to the traveling conditions and a wide range of traveling is possible means that it is possible to achieve both higher acceleration performance and economic efficiency with limited engine horsepower. Therefore, the superiority of the automatic transmission is further improved.

【Example】

In addition to the illustrated example of the present invention, the same mechanism with different numbers of teeth is used, or the distance between the main shaft (5), the center shaft (10) and the drive shaft (12) is changed, and the vehicle is It is needless to say that the respective total reduction ratios can be appropriately adjusted according to the application and the use conditions thereof.
It is effective to use the operation of the fourth speed and the second speed, and normally the first speed is an extra and may be omitted except for the full range running.

【The invention's effect】

As described above, the present invention provides the A gear (7),
Since the D gear (16), C gear (14) and F gear (19) also operate for each of the second speeds, despite the small total number of gears of 6 in total, there are eight forward gear shifting operations. With a small number of clutches (5), the width and weight are significantly reduced, and 4
In the middle and high speed stages above the high speed, the reverse rotation and reduction gear (45) does not operate due to the direct connection by the E clutch (44), and there is an effect that high conduction efficiency can be obtained.

[Brief description of drawings]

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

FIG. 2 is a schematic diagram showing a shift control circuit thereof.

[Explanation of symbols]

 55 Lockup clutch 56 Switching sleeve 57 Radial bearing 58 Starting gear

Claims (1)

[Claims] 1. A main shaft, a center shaft, and a drive shaft, which are set in parallel with each other, wherein A gear and D gear are on the main shaft, B gear and E gear are on the middle shaft, and C gear and F gear are annular. They are arranged on the drive shafts respectively, and the A-clutch and C-clutch are operated on the main shaft, the B-clutch and the one-way clutch are respectively operated on the drive shaft, and the four gears are connected by interlocking with the above-mentioned gears. And by connecting the input shaft and the drive shaft directly when passing through the reverse rotation and reduction gear and when not passing through,
An automatic transmission characterized by being able to obtain a total of eight forward or reverse shifts.