JP2004293770A - Automatic transmission for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lightweight automatic transmission for a vehicle formed compact as a whole. <P>SOLUTION: This automatic transmission for a vehicle is provided with an input shaft 11 for inputting the driving force of an engine, a first pair of planetary gears 12 and a second pair of planetary gears 13 for changing the input driving force, an output gear 14 for outputting the driving force changed by the first and the second pairs of planetary gears, and a counter shaft 21 having a counter gear 22 meshed with the output gear to transmit the driving force, transmitted from the output gear to a differential 30. The output gear 14 is provided being connected to a ring gear R3 of the second pair of planetary gears, and arranged coaxially with the first pair of planetary gears and the second pair of planetary gears between the first pair of planetary gears and the second pair of planetary gears. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an automatic transmission for a vehicle.
[0002]
[Prior art]
FIG. 4 is a diagram showing a conventional automatic transmission for a vehicle, FIG. 4 (A) is an excerpt from Non-Patent Document 1, and FIG. 4 (B) is a skeleton of a main part.
[0003]
A conventional automatic transmission for a vehicle shown in FIG. 4 includes a transmission unit 10 having an input shaft 11 arranged in the vehicle longitudinal direction, a counter gear mechanism 20 also having a counter shaft 21 also arranged in the vehicle longitudinal direction, and a vehicle. A differential 30 for connecting drive shafts 32a and 32b arranged in the left-right direction is provided, for example, so-called vertically mounted on a front engine / front drive (FF) vehicle.
[0004]
[Non-patent document 1]
"4HP18FL MODEL Maintenance Manual", (Germany), ZF Company [0005]
[Problems to be solved by the invention]
However, the above-described conventional automatic transmission for a vehicle has a layout in which the output gear 14 is disposed at the rear end of the input shaft 11 of the transmission unit, and further supported by bearings 18 disposed outside the output gear 14. Therefore, the overall length is increased and the weight is increased.
[0006]
In addition, in order to match the rotation direction of the output gear 14 with the rotation direction of the counter gear 22, it is necessary to arrange the idler gear 50 therebetween, which also causes an increase in weight.
[0007]
SUMMARY OF THE INVENTION The present invention has been made in view of such conventional problems, and has as its object to provide an automatic transmission for a vehicle which is compact in size and light in weight.
[0008]
[Means for Solving the Problems]
The present invention solves the above problem by the following means. Note that, for easy understanding, reference numerals corresponding to the embodiments of the present invention are given, but the present invention is not limited thereto.
[0009]
The present invention provides an input shaft (11) for inputting a driving force of an engine, a first planetary gear set (12) and a second planetary gear set provided coaxially with the input shaft and shifting the input driving force. (13), an output gear (14) that outputs a driving force shifted by the first and second planetary gear sets, and a counter gear (22) that meshes with the output gear, and is transmitted from the output gear. A counter shaft (21) for transmitting the driving force to a differential (30), the output gear (14) being provided in connection with a ring gear (R3) of the second planetary gear set, It is coaxial with the first planetary gear set and the second planetary gear set, and is disposed between the first planetary gear set and the second planetary gear set.
[0010]
[Action / Effect]
Conventionally, as shown in FIG. 4, an output gear is provided at the rear end of the unit, the counter shaft is extended in accordance with the output gear, and the counter gear is arranged at the rear end of the unit. Since the output gear and the counter gear transmit the reduced torque, they must be firmly supported. Conventionally, both sides of the output gear and the counter gear are supported by bearings. For this reason, the overall length has been increased and the weight has been heavy.
[0011]
Therefore, in the present invention, the output gear is connected to the ring gear of the second planetary gear set and is coaxial with the first planetary gear set and the second planetary gear set, and the first planetary gear set and It is arranged between the second planetary gear sets. By doing so, the bearing does not need to be provided at the rear end of the unit, and the overall length can be reduced and the weight can be reduced.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings and the like.
[0013]
FIG. 1 is a skeleton showing a first embodiment of an automatic transmission for a vehicle according to the present invention.
[0014]
The automatic transmission 1 for a vehicle includes a transmission unit 10 having an input shaft (first shaft) 11 arranged in the vehicle front-rear direction, and a counter gear having a counter shaft (second shaft) 21 similarly arranged in the vehicle front-rear direction. This is a six-speed automatic transmission including a mechanism 20 and a differential 30 having drive shafts (third shafts) 32a and 32b arranged in the left-right direction of the vehicle.
[0015]
The transmission unit 10 has a configuration in which a reduction planetary gear set 12, a Ravigneaux-type planetary gear set 13, and an output gear 14 are arranged around an input shaft 11, and these are housed in a transmission case 40.
[0016]
The input shaft 11 is a shaft for inputting the driving force of the engine via a torque converter, and is arranged in a vehicle front-rear direction in parallel with a crankshaft (not shown) of the engine.
[0017]
The reduction planetary gear set 12 is a simple planetary gear set including a sun gear S1, a ring gear R1, and a carrier C1 rotatably supporting a pinion P1 meshing with these gears. The sun gear S1 is always fixed to the transmission case 40. The ring gear R1 is connected to the input shaft 11.
[0018]
The Ravigneaux-type planetary gear set 13 includes a long pinion P2 and a short pinion P3 meshing with each other, a sun gear S2 and a ring gear R3 meshing with the long pinion P2, a sun gear S3 meshing with the short pinion P3, and a long pinion P2 rotatably. It comprises a carrier C2 for supporting and a carrier C3 for rotatably supporting the long pinion P2 and the short pinion P3. Note that the carrier C2 and the carrier C3 are integrated.
[0019]
The output gear 14 is provided between the reduction planetary gear set 12 and the Ravigneaux-type planetary gear set 13. The output gear 14 is connected to the ring gear R3 of the Ravigneaux type planetary gear set 13. The output gear 14 meshes with a counter gear 22 of the counter shaft 21 as described later.
[0020]
The transmission unit 10 also includes low clutch L / C, third speed & fifth speed & reverse clutch 3 & 5 & R / C, high clutch H / C, low & reverse brake L & R / B, It has a second & sixth speed brake 2 & 6 / B and a low one way clutch L / OWC.
[0021]
The low clutch L / C engages / disengages the carrier C1 and the sun gear S3. The third-speed & fifth-speed & reverse clutches 3 & 5 & R / C engage / disengage the carrier C1 and the sun gear S2. The high clutch H / C engages / disengages the carriers C2 and C3 with the input shaft 11. Low & reverse brake L & R / B fixes / releases carriers C2 and C3 to transmission case 40. The second-speed & sixth-speed brakes 2 & 6 / B fix / release the sun gear S2 to / from the transmission case 40. The low one-way clutch L / OWC prevents the carriers C2 and C3 from rotating in the opposite direction to the engine.
[0022]
The transmission unit 10 selects / selects the first to sixth forward speeds and the reverse speed by appropriately engaging / releasing these friction elements for shifting. Specific control contents will be described later.
[0023]
The counter gear mechanism 20 has a counter shaft 21, a counter gear 22, and a reduction gear 23, and transmits the rotation of the output gear 14 to the differential 30. A more detailed description will be described later.
[0024]
Hereinafter, specific shift control will be described with reference to FIG. Note that “○” in FIG. 2 indicates a fastening state.
[0025]
When selecting the first speed, the low clutch L / C is engaged. By doing so, the engine rotation is transmitted as follows. That is, the engine rotation is transmitted from the input shaft 11 to the ring gear R1. Since the sun gear S1 is fixed to the transmission case 40, it acts as a reaction force receiver, and the ring gear R1 decelerates and rotates the carrier C1 in the same direction as the input rotation. The low clutch L / C transmits the reduced rotation to the sun gear S3. By the way, the low one-way clutch L / OWC prevents the carrier C2 from rotating in the opposite direction to the engine rotation, so that the carrier C2 acts as a reaction force receiving member, and the sun gear S3 is connected to the ring gear via the short pinion P3 and the long pinion P2. R3 is decelerated and rotated in the same direction as the engine rotation. This rotation is output from the output gear 5 connected to the ring gear R3.
[0026]
In the first speed selection state, even if an attempt is made to apply the engine brake, the carrier C2 rotates in the same direction as the engine rotation, so that the carrier C2 cannot act as a reaction force receiver, and the engine brake is applied. I can't let it. Therefore, when the engine brake is required, the low & reverse brake L & R / B is engaged as shown by (）) in FIG. 2 to prevent the carrier C2 from rotating in the same direction as the engine rotation. To get the engine brakes at.
[0027]
When selecting the 2nd speed, the low clutch L / C and the 2nd & 6th speed brakes 2 & 6 / B are engaged. By doing so, the engine rotation is transmitted as follows. That is, since the second-speed & sixth-speed brake 2 & 6 / B is engaged, the sun gear S2 acts as a reaction force receiver without rotating. The engine rotation is reduced by the planetary gear set 12 from the input shaft 11 in the same manner as when the first speed is selected, and reaches the sun gear S3 via the low clutch L / C. The sun gear S3 reduces the ring gear R3 via the short pinion P3 and the long pinion P2 in the same direction as the engine rotation, but rotates at a higher speed than when the first speed is selected. This rotation is output from the output gear 5 connected to the ring gear R3. Thus, the forward second speed selection state is realized.
[0028]
When selecting the third speed, the low clutch L / C and the third speed & fifth speed & reverse clutch 3 & 5 & R / C are engaged. By doing so, the engine rotation is transmitted as follows. That is, the engine rotation is reduced by the planetary gear set 12 from the input shaft 11 as in the case of selecting the first speed. This reduced rotation reaches the sun gear S3 via the low clutch L / C and reaches the sun gear S2 via the third-speed & fifth-speed & reverse clutches 3 & 5 & R / C. The sun gear S2 and the sun gear S3 rotate integrally, and the Ravigneaux-type planetary gear set 13 rotates the ring gear R3 at the same speed as the sun gear S2 and the sun gear S3, but at a higher speed than when the second speed is selected. This rotation is output from the output gear 5 connected to the ring gear R3. In this way, the forward third speed selection state is realized.
[0029]
When selecting the fourth speed, the low clutch L / C and the high clutch H / C are engaged. By doing so, the engine rotation is transmitted as follows. That is, the engine speed is reduced by the planetary gear set 12 from the input shaft 11 in the same manner as when the first speed is selected, and reaches the sun gear S3 via the low clutch L / C. On the other hand, the engagement of the high clutch H / C causes the carrier C3 to rotate at the same speed as the engine rotation. Due to this rotation and the reduced rotation to the sun gear S3, the Ravigneaux-type planetary gear set 13 rotates the ring gear R3 in the same direction as the engine rotation, but at a higher speed than when the third speed is selected. This rotation is output from the output gear 5 connected to the ring gear R3. In this manner, the forward fourth speed selection state is realized.
[0030]
To select the fifth speed, the third speed & fifth speed & reverse clutches 3 & 5 & R / C and the high clutch H / C are engaged. By doing so, the engine rotation is transmitted as follows. That is, the engine rotation is reduced from the input shaft 11 by the planetary gear set 12 in the same manner as when the first speed is selected, and reaches the sun gear S2 via the third speed & fifth speed & reverse clutch 3 & 5 & R / C. On the other hand, the engagement of the high clutch H / C causes the carrier C3 to rotate at the same speed as the engine rotation. Due to this rotation and the reduced rotation to the sun gear S2, the Ravigneaux-type planetary gear set 13 rotates the ring gear R3 in the same direction as the engine rotation, but at a higher speed than when the fourth speed is selected. This rotation is output from the output gear 5 connected to the ring gear R3. Thus, the forward fifth speed selection state is realized.
[0031]
When selecting the sixth speed, the high clutch H / C and the second and sixth speed brakes 2 & 6 / B are engaged. By doing so, the engine rotation is transmitted as follows. That is, since the second-speed & sixth-speed brake 2 & 6 / B is engaged, the sun gear S2 acts as a reaction force receiver without rotating. Further, since the high clutch H / C is engaged, the carrier C3 rotates at the same speed as the engine rotation. Therefore, the Ravigneaux-type planetary gear set 13 rotates the ring gear R3 in the same direction as the engine rotation, but at a higher speed than when the fifth speed is selected. This rotation is output from the output gear 5 connected to the ring gear R3. In this way, the sixth forward speed selection state is realized.
[0032]
When reverse is selected, the third-speed & fifth-speed & reverse clutches 3 & 5 & R / C and the low & reverse brake L & R / B are engaged. By doing so, the engine rotation is transmitted as follows. That is, since the low & reverse brake L & R / B is engaged, the carrier C2 acts as a reaction force receiver without rotating. The engine rotation is reduced by the planetary gear set 12 from the input shaft 11 in the same manner as when the first speed is selected, and reaches the sun gear S2 via the third speed & fifth speed & reverse clutches 3 & 5 & R / C. This reduced rotation is reversed by the long pinion P2, and rotates the ring gear R3. This rotation is output from the output gear 5 connected to the ring gear R3. In this way, the backward selection state is realized.
[0033]
The present invention seeks to reduce the size and weight by reviewing the arrangement of the gears. Hereinafter, the gear arrangement of the present invention will be described with reference to FIG.
[0034]
The output gear 14 is provided between the reduction planetary gear set 12 and the Ravigneaux-type planetary gear set 13. The output gear 14 is supported by two bearings 15 attached to a boss 42 extending from an intermediate wall 41 of the transmission case 40.
[0035]
As described above, the counter gear mechanism 20 includes the counter shaft 21, the counter gear 22, and the reduction gear 23. The counter shaft 21 is disposed in the vehicle front-rear direction similarly to the input shaft 11, and a space between the counter gear 22 and the reduction gear 23 is supported by a bearing 24, and an end opposite to the reduction gear 23 is supported by a bearing 25. The counter gear 22 is arranged near the center of the counter shaft 21 and meshes with the output gear 14 of the transmission unit 10. The reduction gear 23 is formed at the tip of the counter shaft 21 and meshes with the final gear 31 of the differential 30. The counter gear mechanism 20 transmits the rotation of the output gear 14 of the transmission unit 10 to the differential 30 via the counter gear 22 → the counter shaft 21 → the reduction gear 23.
[0036]
The bearing 24 is arranged at the same position in the vehicle front-rear direction as the intermediate wall 41, and is arranged between the counter gear 22 and the reduction gear 23.
[0037]
The bearing 25 supports the opposite end of the reduction gear 23.
[0038]
Conventionally, the output gear 14 is provided at the rear end of the unit as described above, and the counter shaft 21 is extended in accordance with the output gear 14, and the counter gear 22 is disposed at the rear end of the unit. Since the output gear 14 and the counter gear 22 transmit the reduced large torque and need to be firmly supported, conventionally, both sides of the output gear 14 and the counter gear 22 are supported by bearings. For this reason, the overall length has been increased and the weight has been heavy. Further, since the idler gear 50 is disposed between the output gear 14 and the counter gear 22 in order to match the rotation direction of the output gear 14, the size of the idler gear 50 and the weight increase are also caused. Was.
[0039]
Therefore, in the present embodiment, as shown in FIG. 3, the output gear 14 is supported by two bearings 15 attached to a boss 42 extending from the intermediate wall 41 of the transmission case 40. The output gear 14 is arranged between the reduction planetary gear set 12 and the Ravigneaux-type planetary gear set 13. With this configuration, it is not necessary to provide a bearing at the rear end of the unit, and the overall length can be reduced and the weight can be reduced. Further, since the output gear 14 is configured to be connected to the ring gear R3 of the Ravigneaux-type planetary gear set 13, the idler gear which has been conventionally required becomes unnecessary, and the weight can be further reduced.
[0040]
In addition, without being limited to the embodiment described above, various modifications and changes are possible within the scope of the technical idea, and it is apparent that they are equivalent to the present invention.
[Brief description of the drawings]
FIG. 1 is a skeleton showing a first embodiment of a vehicular automatic transmission according to the present invention.
FIG. 2 is a diagram showing a state of engagement of a friction engagement element during gear shift control.
FIG. 3 is a diagram showing a gear arrangement.
FIG. 4 is a view showing a conventional automatic transmission for a vehicle.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Automatic transmission 10 for vehicles 10 Transmission unit 11 Input shaft 12 Planetary gear set 13 for reduction 13 Ravigneaux type planetary gear set 14 Output gear 20 Counter gear mechanism 21 Counter shaft 22 Counter gear 23 Reduction gear 30 Differential 31 Final gear 32a, 32b Drive shaft 40 Transmission case

Claims (5)

An input shaft for inputting the driving force of the engine,
A first planetary gear set and a second planetary gear set that are provided coaxially with the input shaft and change the input driving force;
An output gear that outputs a driving force shifted by the first and second planetary gear sets;
A counter shaft that has a counter gear that meshes with the output gear, and that transmits a driving force transmitted from the output gear to a differential;
With
The output gear is provided in connection with a ring gear of the second planetary gear set, is coaxial with the first planetary gear set and the second planetary gear set, and has a first planetary gear set and a second planetary gear set. Located between the two planetary gear sets,
An automatic transmission for a vehicle, comprising: The axial direction of the input shaft and the counter shaft is a vehicle longitudinal direction,
The axial direction of the drive shaft to which the differential is connected is the vehicle left-right direction,
The automatic transmission for a vehicle according to claim 1, wherein: The counter shaft is supported by a first bearing and a second bearing before and after the counter gear,
The automatic transmission for a vehicle according to claim 1 or 2, wherein: The output gear is supported by a bearing attached to a boss extending from an intermediate wall of the transmission case,
One bearing for supporting the counter shaft is provided on the intermediate wall,
The automatic transmission for a vehicle according to claim 3, wherein: The first planetary gear set is a simple planetary gear set including a sun gear, a ring gear, and a carrier that rotatably supports a pinion that meshes with these gears,
The second planetary gear set includes a long pinion and a short pinion that mesh with each other, a sun gear and a ring gear that meshes with the long pinion, a sun gear that meshes with the short pinion, a carrier that rotatably supports the long pinion, and a long gear. A Ravigneaux type planetary gear set having a pinion and a carrier that rotatably supports the short pinion,
The rotation of the first and second planetary gear sets is controlled by a clutch and a brake, and shifts forward six steps.
The automatic transmission for a vehicle according to any one of claims 1 to 4, wherein:

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