JPH0211951A - Automatic transmission - Google Patents

Abstract

PURPOSE:To aim at reduction in a burden due to inertial force in a reverse selector part by installing a reverse selector being connected to a drive shaft selectively via either of a counter reverse gear or a count output gear. CONSTITUTION:When a gear is selected from forward to backward, a reverse selector 28 is slidden to a backward position and engagement between a counter shaft 5 and a counter output shaft 12 is released. Accordingly, a counter reverse gear 16 and the counter shaft 5 rotating in the reverse direction with each other are connected together. With this connection, a drive reverse gear 25, where forward turning effort of the counter shaft 5 has so far been rotated in the forward direction via idler gears 26, 27, is rotated in the reverse direction. In this case, a preceding transmission system from the reverse selector 28 is being rotated in the same direction, and a succeeding transmission system from the counter reverse gear 16 alone is rotated in reverse. Consequently, an impact of inertial force to be imposed on the reverse selector 28 is thus relieved.

Description

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

The present invention relates to a reverse mechanism in an automatic transmission.

[Conventional technology]

As an automobile transmission, for example, Utility Model Application No. 61-2355
There is a continuously variable transmission disclosed in No. 6. In this device, a reverse gear is installed on the inlet side of the power from the engine, and when switching between forward and reverse, the electromagnetic clutch installed between the engine and the continuously variable transmission cuts off the power transmission. The connection with the side shaft is in a free state, so even if you shift gears while the car is moving slightly forward or backward, it will be able to overcome the inertial force applied to the rear gear of the transmission and change the reverse shift. can. However, unlike the configuration of a continuously variable transmission as described above, an automatic transmission using a normal torque converter,
When switching between forward and reverse, the power transmission is not temporarily cut off by an electromagnetic clutch, etc., but rather, in addition to the inertial force mentioned above, the engine torque transmitted via the torque converter is also overcome, causing the reverse shift to occur. It is necessary to perform switching. On the other hand, due to the characteristics of the torque converter, the larger the difference between the rotation speed of the input shaft and the output shaft of the torque converter on the engine side, the larger the output torque of the torque converter, which is applied to the automatic transmission. As the load increases, the degree of shift shock and noise during gear change increases, and the durability of the members that make up the transmission tends to decrease.

[Problem to be solved by the invention]

In this way, in the case of an automatic transmission equipped with a torque converter, unless the vehicle is completely stopped, the drive input gear in the forward gear and the drive reverse gear in the reverse gear rotate in opposite directions. When switching to reverse, the reverse selector is activated in the rotating parts rotating in opposite directions to switch to forward or reverse. Therefore, in this case, all rotating parts from the coupling clutch to the reverse selector must be synchronized with the drive shaft, so the inertia force equivalent to the mass of the rotating body of the power transmission system must be applied to the reverse selector part. You will have to bear the burden. The present invention was made to solve this problem, and by switching forward and backward to the drive shaft side via the reverse gear without changing the rotation direction at the front stage of the reverse selector, It is an object of the present invention to provide an automatic transmission device that can reduce the burden of inertia on the reverse selector section and improve durability.

[Means to solve the problem]

Therefore, in the present invention, countershafts parallel to the main shaft are arranged on the left and right sides of the main shaft driven by the engine via the torque converter, and these countershafts have main gears fixed to the main shaft. In an automatic transmission device in which a counter gear is rotatably installed and meshes with a counter gear at a predetermined gear ratio, the counter shaft and the counter gear can be connected or disconnected via a counter clutch, respectively. includes a counter output gear that meshes with a drive input gear fixed to a drive shaft arranged parallel to the main shaft, and a counter reverse gear that meshes with a drive reverse gear fixed to the drive shaft via an idle gear. The reverse selector is rotatably provided and selectively connected to the drive shaft via either the counter reverse gear or the counter output gear.

[For production]

Therefore, when the reverse selector is operated to select from forward gear to reverse gear, the rotation transmitted via the countershaft is directly transmitted to the drive shaft via the drive reverse gear of the reverse gear, and only the drive shaft side Since the reverse rotation is performed, the burden of inertial force on the reverse selector is reduced.

【Example】

Hereinafter, one embodiment of the present invention will be described in detail based on FIGS. 1 and 2. In FIG. 1, reference numeral 1 denotes a torque converter, which is driven by a drive plate 3 directly connected to a crankshaft 2 of an engine. Main shaft 4 driven by torque converter 1
Counter shafts 5 and 6 are arranged on the left and right sides, respectively. A 4th speed main gear 7.1, a far main gear 8, and 2nd and 3rd speed main gears 9 are fixedly installed on the main shaft 4, and a 1st speed main gear 8.1 that meshes with a 1st speed main gear 8.2 and a 3rd speed main gear 9, respectively. A speed counter gear 10 and a two-speed counter gear 11 are rotatably mounted, and the first speed counter gear 10 and second speed counter gear 11 are connected to the countershaft via a first speed counter clutch 17 and a second speed counter clutch 18, respectively. Further, the counter output gear 12 is rotatably provided on the counter shaft 5, and a counter reverse gear 16 is rotatably provided on the counter shaft 5. The counter output gear 12 or the counter reverse gear 16 is selectively slid by a reverse selector 28 by a servo valve.
By engaging with the , it is possible to switch between forward and backward movement. The countershaft 6 has a 4th speed main gear 7, a 2nd speed and a 3rd speed main gear 7.
4-speed counter gears 13 meshing with the high-speed main gears 9.
and a third-speed counter gear 14 are rotatably mounted, and these counter gears 13, 14 are connected via a fourth-speed counter clutch 19 and a third-speed counter clutch 20, respectively.
It is adapted to be connected to or disconnected from the countershaft 6. On the other hand, a drive input gear 21 is fixed to the drive shaft 22 and is in mesh with a drive reverse gear 25, a parking gear 30, and a counter output gear 12.15 at the same time.
5 meshes with the counter reverse gear 16 via reverse idle gears 26 and 27. In FIG. 2, it is provided on the countershaft 5. Details of the counter output gear 12, counter reverse gear 16, and reverse selector 28 are shown. The bearing structure of the counter shaft 5 and the counter reverse gear 16 is such that an intermediate ring 31 fixed to the casing side of the transmission is sandwiched between the counter shaft 5 and the counter reverse gear 16 by an inner needle 32 and an outer needle 33, respectively. It has an independent coaxial double radial bearing structure. Further, the reverse selector 28 has a structure of a known synchromesh clutch. In addition, the reference numeral 34 in the figure
is a normal needle bearing that pivotally supports the counter output gear 12. In the automatic transmission device configured as described above, for example, the first
When traveling at high speed, the counter output gear 12 and the drive input gear 21 are connected to the counter output gear 12 and the drive input gear 21 via the first speed counter gear 10 and the first speed counter clutch 17 provided on the counter shaft 5 which mesh with the first speed main gear 8 fixedly provided on the main shaft 4. The drive shaft 22 is driven through. Similarly, in the case of second speed, the second speed counter gear 11.2 meshes with the second and third speed main gears 9 fixed to the main shaft 4.
Speed counter clutch 18, counter output gear 1
2. Power is transmitted in the order of the drive input gear 21 and drives the drive shaft 22. In the third speed, the drive shaft 22 is driven via the second and third speed main gears 9, the third speed counter gear 14 and the third speed counter clutch provided on the counter shaft 6, the counter output gear 15, and the drive input gear 21. Similarly, in the case of the 4th speed, a 4th speed counter gear 13, a 4th speed counter clutch 19, and a counter output gear 15 mesh with the 4th speed main gear 7 fixed to the main shaft 4.
, drive input gear 21, and
Drive shaft 22. Therefore, the rotation transmitted to the drive shaft 22 via the counter output gear 12 during the 1st and 2nd speeds, and via the counter output gear 15 during the 3rd and 4th speeds is transmitted to the drive reverse gear. 25, counter reverse gear 1 via reverse idle gear 26.27
6. In this case, the higher the gears such as 3rd and 4th gears are than the lower gears such as 1st and 2nd gears, the higher the rotation speed of the counter reverse gear 1G, which is constantly driven while the vehicle is moving forward. This means that the price has increased. Here, when the vehicle moving forward temporarily stops and switches to reverse, the gear is lowered to the first gear, the lower gear, and then a servo valve (not shown) is operated, and the reverse selector 28 in FIG. is slid from the forward position to the backward position to disengage the counter shaft 5 and the counter output gear 12, and connect the counter reverse gear 16 and the counter shaft 5, which are rotating in opposite directions, to connect the counter shaft 5 and the counter shaft 5. The forward rotational force of the shaft 5 is used to drive the drive reverse gear 25, which has been rotating in the forward direction, to rotate in the reverse direction via the idler gears 26 and 27. In this case, the transmission system before the reverse selector 28 is rotated in the same direction, and the transmission system after the counter reverse gear 16, that is, the idle gear 2
6.27, only the reverse gear train such as the drive reverse gear 25, the drive shaft 22, the drive input gear 21, the counter output gear 15, and the counter shaft 6 are rotated in the reverse direction. Therefore, the inertia force applied to the reverse selector 28 is not affected by the torque converter side. In addition,
Considering that the switching by the reverse selector 28 applies a load to the rotating parts of the counter reverse 16 and the counter shaft 5, it is preferable to adopt a bearing structure as shown in FIG. The relationship between the rotational directions of the inner needle 32 and the outer needle 33, which had been rotating in the same direction, is changed so that the rotational direction of the outer needle 33 instantly follows the rotational direction of the inner needle 32 and rotates in the same direction. It is possible to suppress unpleasant noises and shocks that occur during the above-mentioned switching, and to improve the durability of the rotating parts of the counter reverse gear 16 and the counter shaft 5. In addition, if the relative speed between the counter shaft 5 and counter reverse gear 16 during forward and backward movement becomes large depending on the gear ratio setting of the automatic transmission, etc., the idle gear 26 can be freely adjusted during forward movement as shown in FIG. A second reverse selector 35 is separately provided between the idle gear 26 and the idle gear 27. For example, when switching from forward to reverse, the counter reverse selector 28 is first coupled to the counter shaft 5. , then the second
The configuration may be such that the idle gear 26 and the idle gear 27 are coupled by operating the reverse selector. In the above embodiment, an example was described in which the power transmission system for reversing, such as the counter reverse gear 16 and the reverse selector 28, was provided on the countershaft 5 side. Even if it is configured to be provided on the counter shaft 6 side, the same effects as in the above embodiment can be obtained.

【Effect of the invention】

As explained above, the present invention enables the reverse gear at a later stage to be switched without changing the direction of rotation of the countershaft, which receives the driving force from the engine and the rotational inertia of the power transmission system, when switching between forward and reverse using the reverse selector. Since the switching torque is transmitted to the counter shaft and counter reverse drive shaft only via the row of This has the effect of suppressing noise and shock and improving the durability of the reverse selector portion.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an automatic transmission according to an embodiment of the present invention, FIG. 2 is a side view of the same gear train, and FIG. FIG. 4 is a longitudinal sectional view showing the rotating part, and a schematic configuration diagram showing the main parts of another embodiment. 1... Torque converter, 4... Main shaft,
5.6... Counter shaft, 7... 4th speed main gear, 8... 1st speed main gear, 9... 2nd and 3rd speed main gear, 10... 1st speed counter gear, 11... 2nd speed Counter gear, 12, 15... Counter output gear, 13... 4th speed counter gear, 14... 3rd speed counter gear, 16... Counter reverse gear, 17...
・1st speed counter clutch, 18...2nd speed counterclutch, 19...4th speed counterclutch, 20...3
Speed counter clutch, 21... Drive input gear, 22... Drive shaft, 25... Drive reverse gear, 26.27... Reverse idle gear, 28... Reverse selector, 31... Intermediate ring , 32...inner needle, 33...outer needle.

Claims (1)

[Claims] Counter shafts parallel to the main shaft are arranged on the left and right sides of the main shaft, which is driven by the engine via a torque converter, and these counter shafts mesh with a main gear fixed to the main shaft at a predetermined gear ratio. Install the matching counter gear so that it can rotate freely.
In the automatic transmission device in which the countershaft and the counter gear can be connected or disconnected via counter clutches, one of the countershafts has a drive shaft fixed to the drive shaft arranged parallel to the main shaft. A counter output gear that meshes with the drive input gear and a counter reverse gear that meshes with the drive reverse gear fixed to the drive shaft via the idle gear are rotatably provided. An automatic transmission device comprising a reverse selector selectively connected to the drive shaft via one of the drive shafts.