JPH04351357A - Automatic transmission - Google Patents

Abstract

PURPOSE:To offer an eight-stage gear shifting using a simple and cheap configuration by mounting a plurality of gears on a main, intermediate, and drive shaft which are arranged parallelly, actuating a clutch and a one-way clutch on the main and drive shaft, and by using the action of a reversing/down shifting device. CONSTITUTION:A main shaft 5 is driven by the turbine 4 of a torque converter 3 directly coupled with the output shaft 2 of an engine 1. The main shaft 5 and an intermediate 10 and a drive shaft 12 are installed parallelly. An A-gear 7 and D-gear 16 are mounted on the main shaft 5, while a B-gear 11 and E-gear 18 on the intermediate shaft 10, and C-gear 14 and F-gear 19 on the drive shaft 12. An A one-clutch 6 and B-clutch 17 are actuated on the main shaft 5, while A-clutch 14 and B one-way clutch 21 are operated on the drive shaft 12. Thereby the gears are interlocked with one another, and four-stage shifting is obtained. Further, direct coupling of the input shaft 5 and drive shaft 12 is made either via a reversing/down-shifting device or out of passing through it, and thus eight-stage shifting in total is obtained.

Description

[Detailed description of the invention] [Industrial application field]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a seven-speed automatic transmission for a vehicle with a transversely mounted front two wheels (or two rear wheels).

[Conventional technology]

[0002] When applying a three-axis automatic transmission to a two-wheel drive vehicle with a transversely mounted front engine, there is a problem that the C gear and F gear protrude to the left of the torque converter, shortening the left propeller shaft. However, at high speeds, there was the problem of additional gear loss due to the reduction gear.

[Problem to be solved by the invention]

[0003] This invention uses six gears in total, two gears each with different diameters on three axes, a main shaft, a center shaft, and a drive shaft, which are arranged parallel to each other. Despite being able to obtain high conduction efficiency and 7-speed forward shifting without using a motor, the number of gears and clutches used can be significantly reduced, resulting in smaller size, lighter weight, and cost reduction. The purpose is

[Means to solve the problem]

[0004] The present invention will be explained below with reference to the drawings. FIG. 1 is a plan sectional view showing one embodiment of an automatic transmission according to the present invention, and FIG. 2 is a transmission control circuit diagram thereof. The torque converter (
The turbine (4) of 3) directly drives the main shaft (5) on the right side, and the A gear (7) (number of teeth 17), which is driven via the A one-way clutch (6), is mounted on the annular shaft (8). An annular center shaft (10
) B gear (11) (number of teeth 38) provided integrally on the top
via the annular drive shaft (12) and the annular shaft (1) concentric with the annular drive shaft (12).
3) The C gear (14) (50 teeth) installed above is A
Activated via clutch (15). D gear (16) (
The number of teeth (22) is likewise freely rotatable on the annular shaft (8) and is actuated via the B clutch (17). E gear (1
8) (number of teeth 18) is provided integrally with the center shaft (10), and F
A gear (19) (number of teeth: 46) is provided on the drive shaft (12) so as to be freely rotatable via the annular shaft (20), and is actuated on the drive shaft (12) via the B one-way clutch (21). do. The main shaft (5), the center shaft (10), and the drive shaft (12) are all provided 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 of the distance between the center shaft (10) and the main shaft (5).
．． By arranging these three axes not necessarily on the same plane (as shown in the figure), it is possible to reduce the size and improve the degree of freedom in design. A one-way clutch (6), B
Since it is installed on the left side of the clutch (17) and the oil pump (not shown) is driven by a belt, the C gear (14) and F gear (
19) can be placed close to the torque converter (3), there is an advantage that the left propeller shaft (not shown) can be made longer. Drum (23) on the right side of the drive shaft (12)
A switching device (24) is provided which operates via a large sun gear (25) (24 teeth), a ring gear (27) (66 teeth) via a long pinion (26), a D clutch (
28), the annular input shaft (3
0). Short pinion (31) on carrier (29)
) transfers the retarding action of reverse rotation to the carrier (2
9). The rotation of the input shaft (30) is controlled by the ring gear (34) of the differential (33) and the double pinion (3).
5) The carrier (37) side connects the left extraction shaft (
38) to the left wheel (not shown), and the sun gear (39) side to the right wheel (not shown) via the right extraction shaft (40). E gear with a large load (
18) has a larger tooth pitch than B gear (11), and C gear
The clutch (41) is installed with a larger diameter than the B clutch (17). The C clutch (41) is used when the drive shaft (12) and the input shaft (30) are directly connected, and is installed in the drum (23).

[Effect]

The output of the engine (1) is used in a torque converter (3) to perform a known predetermined operation to rotate the main shaft (5). In 1st gear, the B clutch (17) does not operate, only the A one-way clutch (6) operates, and the rotation of the main shaft (5) is controlled by A gear (7), B gear (11), and E gear (18). F
B one-way clutch (21) via gear (19)
) causes the large sun gear (25) to rotate through the drive shaft (12) and by operating the switching device to the right.
The carrier (29), which is connected to the differential gear (33) and is integral with the input shaft (30), is at rest. D clutch (28)
When the rotating ring gear (27) is fixed to the case (22) and stopped by gradual operation, the input shaft (30)
begins to rotate in the forward direction, and the reduction ratio on the drive shaft (12) in this case becomes 5,710, so the total reduction ratio on the input shaft (30) becomes 21,412. 2nd gear is also set to A gear (7) by the operation of only A one-way clutch (6).
), B gear (11) and C gear (14), the A clutch (14) is operated, and the reduction ratio on the drive shaft (12) is 2,941, and the total reduction ratio of the input shaft (30) is The reduction ratio is 11
,028. In 3rd gear, only the B clutch (17) is operated, and the D gear (16), E gear (18) and F gear (
19), the reduction ratio of the drive shaft (12) is 2,090, and the total reduction ratio of the input shaft (30) is 7,837 due to the operation of the B one-way clutch (21). Fourth
The speeds are the same as 1st gear: A gear (7), B gear (11),
The input shaft (
30) and the drive shaft (12) are directly connected by operating the C clutch (41), so the total reduction ratio is 5,710. 5th gear is set to D gear (1
6), E gear (18), B gear (11) and C gear (14)
), the A clutch (15) is activated, and the drive shaft (
12) A reduction ratio of 1,075 can be obtained with the C clutch (
41) is released and the D clutch (28) is activated, the total reduction ratio of the input shaft (30) becomes 4,031. 6th gear is the same as 2nd gear, A one-way clutch (6)
A gear (7), B gear (11) and C
Via the gear (14), actuate the A clutch (14) and further actuate the C clutch (41) to
) and the drive shaft (12) are again directly connected, and the total reduction ratio is 2.
,941. In 7th gear, like 3rd gear, only the B clutch (17) is operated, and the D gear (16) and E gear (1
8) Activate the B one-way clutch (21) via the F gear (19) and obtain a total reduction ratio of 2,090 on the directly connected drive shaft (12) and input shaft (30). It is something. Although 8th gear can achieve the same total reduction ratio of 1,075 as 4th gear, the distance from 7th gear is too large and it is not suitable for anything other than engine braking, so 7th gear is usually used for practical use. It is highly effective. When reversing, the operation of 1st or 2nd gear is moved to the left when the 3-switching device (24) is stopped, and the total reduction ratio is set to 25,
695 or 13,234. When these are connected directly by C clutch (41) operation, the D clutch (28) is always released and the ring gear (27) freely rotates together with the carrier (29), so the reversal and deceleration device (42) is used. There is an advantage that there is no gear loss and no noise is generated. Also, A, B one-way clutches (6
) (21), the shock is prevented by the operation of the C clutch (41) or the D clutch (28) in 1st and 4th speeds, which contributes to further miniaturization of the device. ing. Starting in 2nd, 3rd, and 4th gears during economy driving is automatically possible as is known by means of a known computer-based control (see FIG. 2). 4 clutches A, B, C, D (15) (17)
(41) and (28) are pressurized by a pump and controlled by a known control circuit shown in FIG.
3) (44), (45), and (46), these clutches are individually operated in a predetermined manner, and each clutch has a cylinder (47), a piston (48),
A spring (49) and a multi-disc clutch (50) are installed as known. Next, as a feature of the automatic transmission of the present invention,
The operation of the 1st to 7th gears is such that each clutch is always released before the next operation, so there is good responsiveness to the next gear. That is, in the first speed of the A one-way clutch (6), the D clutch (28) is opened and waiting before its operation, and in the second speed (hereinafter referred to as "opening"), the A one-way clutch ( 15) is opened, and in third gear, the B clutch (17
) is open, in 4th gear, C clutch (41) is open, and in 5th gear, A clutch (15) and B clutch (17) are open.
) and D clutch (28) are both open, and in 6th gear, C
The clutch (41) can be opened again, and in 7th gear, the A clutch (15) can be opened, and when reversing, the switching device (24) can be opened.
After activation in a known manner (not shown), the D clutch (28) (A clutch 15 and A clutch 15 in second gear reverse) is opened. These are due to the fact that while each clutch is operating, the other clutches are at rest, so the spring (49) loosens and opens them, waiting for the next speed. This makes it possible to change gears. In this embodiment, the stage ratio of the total reduction ratio of each speed stage is almost the same, and constitutes an ideal torque distribution. When starting in 2nd gear during economy driving, 3rd gear is omitted and then shifts to 4th gear, and similarly when starting in 3rd gear, 4th gear is omitted and then shifts to 5th gear, resulting in a lower speed. Automatically shifts gears based on the number of shocks. The 7th gear can be called the 2nd overdrive.
This is more advantageous for economical driving at high speeds.

【Example】

In addition to the illustrated examples of the present invention, similar mechanisms with different numbers of teeth may be used, or the main shaft (5), the center shaft (10) and the drive shaft (
12) By changing the distance between each axle, it is of course possible to adjust each total reduction ratio appropriately according to the purpose of the vehicle and its usage conditions. However, an E clutch (not shown) may be provided in place of the B one-way clutch (21) and added at the low speed stage of the third gear.

【Effect of the invention】

As described above, the present invention includes the A gear (7),
Because the D gear (16), C gear (14), and F gear (19) each serve the same purpose as two speeds, despite the small total number of gears (six in total), there are seven forward gears. With a small number of clutches (4), the width and weight are significantly reduced, and 4
In the high speed stage, the reversing and decelerating device (42) does not operate due to direct connection by the C clutch (41), which has the effect of obtaining high transmission efficiency.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional plan view showing one embodiment of an automatic transmission of the present invention.

FIG. 2 is a schematic diagram showing the speed change control circuit.

[Explanation of symbols]

51 Parking gear 52 Lock-up clutch 53 Switching sleeve 54 Radial bearing

Claims (1)

[Claims] Claim 1: Consisting of a main shaft, a center shaft, and a drive shaft, each set in parallel, the A gear and D gear are placed on the main shaft, the B gear and E gear are placed on the center shaft, and the C gear and F gear are arranged in an annular shape. The A one-way clutch and the B clutch are respectively arranged on the drive shaft, and the A one-way clutch and B clutch are operated on the main shaft, and the A clutch and B one-way clutch are respectively operated on the drive shaft, and are interlocked with the above-mentioned gears. By directly connecting the input shaft and the drive shaft, a total of 8 forward or reverse speeds can be obtained, whether through a reversing/reducing device or not. Automatic transmission.