JPH0791506A - Gear speed change device - Google Patents

Abstract

PURPOSE:To downsize a braking means by applying braking torque of the braking means to element through reducing counter gear pair when specific elements of a planetary gear mechanism are to be fixed to obtain specific reduction steps, thereby reducing load torque of the braking means. CONSTITUTION:An input shaft 1 is connected to an engine through a torque converter 3, and an output shaft 2 is connected to a differential device 4. Then, a low speed counter gear pair GL, a high speed counter gear pair GH and a backward counter gear pair GR in order from right to left are disposed on the output shaft 2. A single pinion type planetary gear mechanism GP is disposed on the output shaft 2, in which a brake B2 is disposed for fixing a sun gear 40 selectively to a carrier 42 through a low speed counter gear pair GL, etc. The brake speed exhibits reduction act when the gear ratio of the low speed counter gear pair ratio of the low speed counter gear pair G6 become larger than 1. Accordingly, even when torque capacity of the brake B2 is small, the braking force for fixing the carrier 42 becomes large.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear transmission that sets a plurality of shift speeds by transmitting torque between an input shaft and an output shaft by a planetary gear mechanism and a plurality of counter gear pairs, In particular, the present invention relates to a gear transmission that can be used as a transmission for vehicles.

[0002]

2. Description of the Related Art In a transmission device of this type, a predetermined shift speed is set by the shifting action of a plurality of counter gear pairs arranged between an input shaft and an output shaft and the shifting action of a planetary gear mechanism. Therefore, since it is not necessary to arrange the members that perform the gear shifting action in series in the axial direction, it is possible to reduce the overall axial length. One example is JP-A-62.
-49053 gazette. Briefly explaining this, three counter drive gears are arranged coaxially with the input shaft connected to the torque converter, and a clutch for selectively connecting them to the input shaft is further provided. A counter driven gear that is paired with the counter drive gear is arranged coaxially with the output shaft, and a Ravigneaux type planetary gear mechanism is arranged coaxially with the output shaft. A clutch that selectively connects a predetermined element of the planetary gear mechanism to the counter driven gear and a brake that fixes the predetermined element of the planetary gear mechanism are provided. Among the brakes, a brake that fixes the common carrier of the planetary gear mechanism to set the reverse gear is provided at a position that meshes with a gear mounted on the common carrier and fixes a gear having a diameter larger than that of the gear.

Therefore, when the counter gear pair involved in torque transmission is selected by the clutch, the gear shift action is generated by the selected counter gear pair, and at the same time, the input element to the planetary gear mechanism is selected and the planetary gear mechanism is selected. Since a predetermined gear shifting action is performed, a plurality of gear stages are set by the gear shifting action combining these counter gear pairs and the planetary gear mechanism. Further, the reverse speed is achieved by fixing the common carrier of the planetary gear mechanism by the brake via the counter gear pair for increasing the speed from the input shaft to the output shaft side, and by inputting in that state to one sun gear. , It is set by the reversing action of the planetary gear mechanism.

[0004]

The planetary gear mechanism performs a decelerating action, a speed increasing action, and a reversing action by appropriately setting an input element and a fixed element. The input shaft and the output arranged in parallel with each other as described above. In the configuration in which the planetary gear mechanism is provided coaxially with any one of the shafts, a brake for fixing the predetermined rotating element is provided on the shaft side different from the shaft on which the planetary gear mechanism is provided, The number of frictional engagement devices arranged coaxially can be reduced, and the axial length can be shortened easily. However, in the above-mentioned conventional device, the brake for fixing the carrier is connected to the carrier via the counter gear pair for speed-up, so that it is necessary to increase the size of the brake and increase its capacity. That is, since the diameter of the gear connecting the carrier is larger than the diameter of the gear directly fixed by the brake, the torque for fixing the carrier is doubled according to the gear ratio of the counter gear pair. Since it acts on the brake, it is necessary to use a large brake in order to increase the torque capacity of the brake, and as a result, the configuration of the gear transmission as a whole becomes large, which in turn causes an increase in weight. is there.

The present invention has been made in view of the above circumstances, and it is intended to reduce the size and weight of a gear transmission that uses a counter gear pair and a planetary gear mechanism to set a plurality of gears including a reverse gear. The purpose is.

[0006]

In order to achieve the above-mentioned object, the present invention has an input shaft and an output shaft arranged in parallel with each other, and coaxially with any one of the shafts. A planetary gear mechanism having three elements, a sun gear, a carrier, and a ring gear, is provided, and any one of those elements is connected to the one shaft, and the other two elements are connected via a plurality of counter gear pairs. To stop rotation of a predetermined element of the planetary gear mechanism in a gear transmission which is selectively connected to the other shaft and further provided with a brake means for selectively fixing at least one of these two elements. Braking means is arranged so as to fix another gear having a small diameter which meshes with a gear connected to the element.

[0007]

In the device of the present invention, the counter gear pair performs a gear shifting action according to its gear ratio, and the planetary gear mechanism is fixed by fixing certain elements of the planetary gear mechanism and using other elements as input elements. It is possible to set a plurality of shift speeds by performing a gear shifting action and a combination of these gear shifting actions. When a predetermined element in the planetary gear mechanism is fixed to set a predetermined gear such as the first speed, the element is a counter gear pair that performs a deceleration action when transmitting torque to the element. It is fixed by the brake via. That is, the gear directly fixed by the brake to the gear connected to the element has a small diameter, and therefore the torque applied to the brake for fixing the element is small.

[0008]

EXAMPLES The present invention will now be described in detail based on examples. FIG. 1 is a skeleton diagram showing an embodiment of the present invention. The gear transmission shown here is used for, for example, a vehicle transmission, and an input shaft 1 and an output shaft 2 are parallel to each other. The input shaft 1 is connected to the engine (not shown) via the torque converter 3, and the output shaft 2 is connected to the differential 4.

A low speed counter gear pair GL, a high speed counter gear pair GH and a reverse drive counter gear pair GR are provided coaxially with the shafts 1 and 2 from the right side of FIG.
That is, when transmitting torque from the input shaft 1 side to the output shaft 2 side, the low speed counter gear pair G performs deceleration action.
An L drive gear 10 is arranged coaxially with the input shaft 1 and rotatable with respect to the input shaft 1. A driven gear 11 meshing with the drive gear 10 has a larger diameter than the drive gear 10 It is arranged coaxially with the shaft 2 and rotatable with respect to the output shaft 2. The drive gear 20 of the high speed counter gear pair GH is arranged coaxially with the input shaft 1 and rotatably with respect to the input shaft 1, and the driven gear 21 meshing with the drive gear 20 is coaxial with the output shaft 2 and outputs. Axis 2
It is rotatably arranged with respect to. Further, the drive gear 30 of the reverse stage counter gear pair GR is arranged coaxially with the input shaft 1 and rotatable with respect to the input shaft 1.
The driven gear 31 is arranged coaxially with the output shaft 2 and rotatably with respect to the output shaft 2. The drive gear 30 and the driven gear 31 are connected to the idle gear 3
It meshes via 2.

The drive gears 10, 20, 30 and the input shaft 1 are selectively connected to each other. Specifically, specifically, the drive gear 3 of the reverse counter gear pair GR is used.
First clutch C1 for selectively connecting 0 and the input shaft 1
, A second clutch C2 for selectively connecting the drive gear 10 of the low speed counter gear pair GL and the input shaft 1, and a second clutch C2 for selectively connecting the drive gear 20 of the high speed counter gear pair GH and the input shaft 1. A third clutch C3 is provided.

On the other hand, each driven gear 1 is provided on the output shaft 2 side.
In addition to 1, 2, 31 and 31, a single pinion type planetary gear mechanism GP is arranged coaxially with the output shaft 2. this is,
The sun gear 40, a ring gear 41 arranged concentrically with the sun gear 40, and a carrier 42 that holds a pinion gear meshing with these gears are elements, and the sun gear 40 is connected to the driven gear 31 of the reverse counter gear pair GR. Further, the ring gear 41 is connected to the output shaft 2. Further, the carrier 42 is a low speed counter gear pair GL.
The driven gear 11 and the driven gear 21 of the high speed counter gear pair GH are connected to each other.

That is, this planetary gear mechanism GP uses a ring gear 41 as an output element, and a sun gear 40 and a carrier 42.
Are used as input elements or fixed elements. Therefore, the first brake B1 and the low speed counter gear pair GL for selectively fixing the sun gear 40 (that is, the driven gear 31 of the reverse gear pair GR) are used. A second brake B2 for fixing the carrier 42 is provided. This second brake B2 is a low speed counter gear pair G
The L drive gear 10 is configured to be fixed to the housing HU, so that the low speed counter gear pair GL has a gear ratio larger than "1" from the input shaft 1 side to the output shaft 2 side. Second, to slow down
Even if the torque capacity of the brake B2 is small, the braking force for fixing the carrier 42 is large. In other words, the carrier 42 is not directly fixed but fixed via the low speed counter gear pair GL, so that the second brake B is fixed.
2 is being miniaturized.

Further, by connecting two elements of the planetary gear mechanism GP, the whole planetary gear mechanism GP is integrated into a fourth unit.
A clutch C4 is provided between the sun gear 40 and the carrier 42. In FIG. 1, reference numeral 5 indicates an output gear,
The output gear 5 meshes with the differential 4.

In the above apparatus, each clutch C1, ..., C4
By engaging the brakes B1 and B2 as shown in FIG. 2, it is possible to set a shift speed of five forward gears and one reverse gear. Note that FIG. 2 is a diagram showing an engagement operation table. In FIG. 2, a circle mark indicates engagement and a blank column indicates a released state.

That is, in the first speed, the planetary gear mechanism is engaged by engaging the first clutch C1 to connect the input shaft 1 to the drive gear 30 of the reverse counter gear pair GR and engaging the second brake B2. The carrier 42 of GP is fixed and set. Therefore, the sun gear 4 of the planetary gear mechanism GP is transmitted from the input shaft 1 via the reverse counter gear pair GR.
The torque is inverted to 0 and transmitted. On the other hand, in the planetary gear mechanism GP, the carrier 42 is fixed by the second brake B2 via the low speed counter gear pair GL, so that the ring gear 41 is decelerated in the opposite direction to the sun gear 40 and rotates. It will be. Therefore, the rotational direction reversed by the reverse counter gear pair GR is restored by the planetary gear mechanism GP, so that the output shaft 2 rotates in the forward traveling direction. In this case, the load torque for fixing the carrier 42 acts on the second brake B2, but the driven gear 11 to which the carrier 42 is connected is more likely to move to the drive gear 10 directly fixed by the second brake B2. Has a large diameter, that is, the carrier 42 is fixed via the counter gear pair 10 for reduction,
The load torque acting on the second brake B2 becomes small.
At the first speed, the reverse counter gear pair GR and the planetary gear mechanism GP perform deceleration, so that the gear ratio has a value corresponding to those gear ratios. Specifically, the gear ratio of the reverse counter gear to GR is ρR, and the planetary gear mechanism GP is
Of the gear ratio (ratio of the number of teeth of the sun gear and the ring gear) of ρP
Then, the gear ratio of the first speed is represented by “ρR / ρP”.

In the second speed, the second clutch C2 is engaged to connect the input shaft 1 to the drive gear 10 of the low speed counter gear pair GL, and the fourth clutch C4 is engaged to connect the planetary gear mechanism GP. The sun gear 40 and the carrier 42 are connected to each other, whereby the entire planetary gear mechanism GP is integrally rotated. That is, the torque of the input shaft 1 is transmitted to the carrier 42 of the planetary gear mechanism GP via the low speed counter gear pair GL. On the other hand, since the entire planetary gear mechanism GP rotates integrally due to the engagement of the fourth clutch C4, the output shaft 2 rotates in the same direction at the same speed as the driven gear 11 of the low speed counter gear pair GL. To do. Therefore, at this second speed, only the low speed counter gear pair GL is involved in the gear shifting operation between the input shaft 1 and the output shaft 2, and therefore the gear ratio is set to the gear ratio of the low speed counter gear pair GL as ρL. Then, it is represented by "ρL".

In the third speed, the second clutch C2 is engaged to set the input shaft 1 to the drive gear 1 of the low speed counter gear pair GL.
It is set by connecting to 0 and fixing the sun gear 40 of the planetary gear mechanism GP by engaging the first brake B1. Therefore, from the input shaft 1 to the carrier 42,
Since the torque is transmitted through the low speed counter gear pair GL, the carrier 42 rotates at a reduced speed with respect to the input shaft 1. In the planetary gear mechanism GP, the sun gear 40 serves as a fixed element and the carrier 42 serves as an input element. Therefore, the ring gear 41 serving as an output element is accelerated with respect to the carrier 42 and rotates in the same direction as the carrier 42. Therefore, the output shaft 2 has a lower speed counter gear pair G than the input shaft 1.
The speed is reduced by L and is increased by the planetary gear mechanism GP, and the gear ratio is represented by "ρL / (1 + ρP)".

In the fourth speed, the third clutch C3 is engaged to set the input shaft 1 to the drive gear 2 of the high speed counter gear pair GH.
0 and the fourth clutch C4 is engaged to connect the sun gear 40 and the carrier 42 of the planetary gear mechanism GP. That is, the planetary gear mechanism GP is set to a state in which the whole is integrally rotated, and the high speed counter gear pair G is set.
The torque is transmitted from the input shaft 1 to the planetary gear mechanism GP via H. Therefore, the planetary gear mechanism GP has the input shaft 1
The rotation speed is changed by the high-speed counter gear pair GH with respect to the rotation speed of, and the rotation speed is transmitted to the output shaft 2 as it is.
Only H does. As a result, the gear ratio at the 4th speed is "ρH" if the gear ratio of the high speed counter gear to GH is ρH.
It is represented by.

In the fifth speed, the third clutch C3 is engaged to set the input shaft 1 to the drive gear 2 of the high speed counter gear pair GH.
It is set by connecting to zero and fixing the sun gear 40 by engaging the first brake B1. Therefore, as in the case of the third speed, the sun gear 40 is input to the carrier 42 as the fixed element to the planetary gear mechanism GP, so that the planetary gear mechanism GP performs the speed increasing action. The carrier 42, which is an input element thereof, rotates at a rotational speed changed by the high speed counter gear pair GH with respect to the input shaft 1. Since the high-speed counter gear pair GH and the planetary gear mechanism GP thus perform the gear shifting operation, the gear ratio at the fifth speed is represented by "ρH / (1 + ρP)".

In the reverse gear, the first clutch C1 is engaged to connect the input shaft 1 to the drive gear 30 of the reverse counter gear pair GR, and the fourth clutch C4 is engaged to engage the sun gear 40 and the carrier 42. Set by connecting and. Therefore, the sun gear 40 is attached to the planetary gear mechanism GP.
However, since the fourth clutch C4 is engaged, the entire unit rotates as a whole.
The output shaft 2 has a reverse counter gear pair G with respect to the input shaft 1.
It rotates at the number of revolutions changed by R, and its rotation direction is opposite to the rotation direction at the forward speed because the reverse counter gear pair GR has the idle gear 32. That is, the gear ratio is represented by "-ρR".

Therefore, in the gear transmission shown in FIG.
When setting the first speed, the carrier 4 of the planetary gear mechanism GP
The rotation of the second brake B2 is stopped by the second brake B2, but since this is performed via the counter gear pair 10 for deceleration, the load torque of the second brake B2 becomes small, and especially at such a low speed, the planetary gear mechanism GP Since the reaction force required to fix the rotating element of No. 2 becomes large, the second method by fixing the carrier 42 via the low speed counter gear pair 10
The effect of reducing the load torque of the brake B2 is remarkable.

The gear transmission shown in FIG. 1 is not limited to the case where the reverse counter gear pair GR is set to the reverse gear.
The counter gear pair and the planetary gear mechanism can be commonly used by being used also when setting the first speed. Since the gear ratio of the first speed becomes a value determined by the gear ratio of the reverse counter gear pair GR and the gear ratio of the planetary gear mechanism GP, the gear ratio of the entire forward gear can be widened. .

The present invention is not limited to the above embodiment, and the arrangement of each counter gear pair and the planetary gear mechanism can be changed as required. The planetary gear mechanism used is not limited to the single pinion type, but may be the double pinion type. The clutch and brake may be a combination of a multi-plate structure and a one-way clutch.

[0024]

As is apparent from the above description, according to the gear transmission of the present invention, when a predetermined element of the planetary gear mechanism is fixed in order to set a predetermined shift speed, the braking torque of the braking means is changed. Since it acts on the element via the pair of counter gears for deceleration, the load torque of the braking means is reduced, and as a result, the required torque capacity of the braking means is reduced, that is, the braking means can be downsized. Accordingly, the overall structure of the gear transmission can be reduced in size and weight.

[Brief description of drawings]

FIG. 1 is a skeleton diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing an engagement operation table of clutches to be engaged in order to set each shift speed in the embodiment.

[Explanation of symbols]

 1 Input shaft 2 Output shaft GL Low speed counter gear pair GH High speed counter gear pair GR Reverse drive counter gear pair GP Planetary gear mechanism C1, ~ C4 Clutch B1, B2 Brake

Claims (1)

[Claims] 1. An input shaft and an output shaft are arranged in parallel with each other, and a planetary gear mechanism having three elements, a sun gear, a carrier, and a ring gear, is provided coaxially with any one of the shafts. , One of those elements is connected to the one shaft, and the other two elements are selectively connected to the other shaft via a plurality of counter gear pairs, and at least these two elements are connected. In a gear transmission provided with a brake means for selectively fixing any one of them, a brake means for stopping rotation of a predetermined element of the planetary gear mechanism has a small diameter that meshes with a gear connected to the element. A gear transmission, which is arranged so as to fix other gears.