KR19980016990A - Gear train of car 4-speed automatic transmission - Google Patents

Abstract

By applying a compound planetary gear set that is radially combined, the object is to provide a gear train of a four-speed automatic transmission for a vehicle that enables the design of an automatic transmission having a very short length and is easy to apply to a transverse front wheel drive vehicle;

The second simple planetary gear set is surrounded by the outer ring gear of the first simple planetary gear set so that the ring gear of the first simple planetary gear set can act as the sun gear of the second simple planetary gear set. The planetary carriers of a simple planetary gear set are interconnected to act as input and reaction elements, retaining four operating elements, of which at least two elements are selected and set as input elements and reaction elements at each shift stage. A composite planetary gear set for shifting;

Clutch means for actuating such that the ring gear of the first simple planetary gear set and the planetary carrier of the first simple planetary gear set are selectively input elements;

A sun gear and a ring gear of said first simple planetary gear set, and brake means for actuating each planetary carrier selectively to be a reaction element;

It provides a gear train of a four-speed automatic transmission for a vehicle comprising a.

Description

Gear train of car 4-speed automatic transmission

1 is a block diagram of a gear train according to the present invention.

2 is a view for explaining the operation of the present invention by lever analysis method.

3 is an operating table of friction elements for each shift stage to obtain a gear ratio of 4 forward speeds and 1 reverse speed of the 2nd gear train.

The present invention relates to a gear train of a four-speed automatic transmission for a vehicle. More specifically, by applying a compound planetary gear set that is radially combined, it is possible to design an automatic transmission having a very short length, and thus it is applicable to a lateral front wheel drive vehicle. It relates to a gear train of a four-speed automatic transmission for the vehicle to facilitate.

BACKGROUND ART In general, an automatic transmission for a vehicle includes a transmission control unit that automatically controls a transmission ratio in accordance with a change in a traveling speed and a load of a vehicle.

The transmission control unit controls a plurality of friction elements installed in the gear train in an active or non-operating state so that any one of the three elements of the planetary gear set (sun gear, ring gear, planet carrier) is an input element, and other elements. Select the reaction element to adjust the output speed.

The composite planetary gear device used as the automatic transmission device for the vehicle includes a lavender type, a Simpson type, and a two-simpson type planetary gear device.

And the composite planetary gear device as described above has a structure in which the planetary carriers are connected to each other in order to be used as a transmission means of the vehicle, or having a structure in which the sun gear is shared and the planetary carrier and the ring gear is directly connected, or the planetary carrier and the ring Gears are directly connected to each other, that is, two planetary gear sets are connected in the axial direction.

Accordingly, since the length in the axial direction is increased, the transmission length is increased, particularly in the case of the lateral front wheel drive type automatic transmission, which is very disadvantageous in terms of mountability, a lot of efforts are required to shorten the length of the design.

Therefore, the present invention has been invented to meet the requirements as described above, the object of the present invention is to apply a compound planetary gear set that is radially combined, it is possible to design an automatic transmission with a very short length, transverse front wheel drive vehicle To provide a gear train of a four-speed automatic transmission for the vehicle to facilitate the application.

In order to realize the above object, the present invention provides a second simple planetary gear set surrounded by a ring gear of the first simple planetary gear set so that the ring gear of the first simple planetary gear set is also a sun gear of the second simple planetary gear set. Combined to act, but retaining four actuation elements by interconnecting the planetary carriers of the first and second simple planetary gear sets to actuate input and reaction forces, with at least two elements in each shift And a compound planetary gear set selected from an input element and a reaction force element so as to shift.

Clutch means for actuating such that the ring gear of the first simple planetary gear set and the planetary carrier of the first simple planetary gear set are selectively input elements; A sun gear and a ring gear of said first simple planetary gear set, and brake means for actuating each planetary carrier selectively to be a reaction element; It provides a gear train of a four-speed automatic transmission for a vehicle comprising a.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention that can specifically realize the above object will be described in detail.

1 is a view showing the gear train of the embodiment according to the present invention, the power generated from the engine 2 is a torque conversion through the torque converter 4 is input to the composite planetary gear set 6 to make a shift do.

At this time, the composite planetary gear set 6 is input to at least one element by the selective operation of the clutch means consisting of a plurality of clutches 8, 10, a plurality of brakes 12, 14, 16 By selective operation of the brake means consisting of) at least one element in all the operating range except the forward three speeds are operated as a reaction force element is shifting.

Torque converter (4) for converting the torque generated from the engine (2) in the above is a pump impeller (18) which is directly connected to the crankshaft of the engine (2) and rotates; A turbine runner 20 which is disposed to face the pump impeller 18 and rotates together by oil ejected; And a stator 22 disposed between the pump impeller 18 and the turbine runner 20 to change the flow of oil to increase the rotational force of the pump impeller 18.

Accordingly, when the engine rotates, the oil filled in the torque converter 4 is ejected from the pump impeller 18 and supplied to the turbine runner 20 to drive the turbine runner 20 and then flow into the stator 22. .

In addition, the oil introduced into the stator 22 changes the direction and repeats the flow of the oil into the pump impeller 18. At this time, the turbine runner shared by the stator 22 is rotated by the rotation of the stator 22. A difference is generated between the rotational force of 20 and the rotational force of the pump impeller 18 so that torque conversion is achieved.

The second planetary gear set 6, which receives power from the torque converter 4, is arranged in the same line on the rear side of the input shaft 24 connected to the turbine runner 20 of the torque converter 4. It is arranged at 26.

The composite planetary gear set 6 consists of first and second simple planetary gear sets 28 and 30 which are radially combined, which is outside the ring gear 32 of the first simple planetary gear set 28. Another second simple planetary gear set 30 is enclosed so that the ring gear 32 of the first simple planetary gear set 28 can act as a sun gear of the second simple planetary gear set 30. Planetary carriers 34 and 36 of the first and second simple planetary gear sets 28 and 30 are connected as interconnecting members 38.

The first clutch 8, which acts as a clutch means 8 for transmitting the power of the engine 2 to the composite planetary gear set 6, has a ring gear 32 of the first simple planetary gear set 28. Is interposed between the input shaft 24 and the second clutch 10 is interposed between the planetary carrier 34 of the second simple planetary gear set 28 and the input shaft 24.

Accordingly, the selective operation of the clutches 8 and 10 causes the elements 32 and 34 to be connected thereto to be optional or two elements acting simultaneously as input elements.

Of course, when the planetary carrier 34 of the first simple planetary gear set 28 acts as an input and reaction force element, the planetary carrier 36 of the second simple planetary gear set 30 connected thereto is also interlocked.

Further, the first brake 12 forming the brake means is interposed between the sun gear 40 of the first simple planetary gear set 28 and the transmission housing 42, and the second brake 14 is the first simple planetary. The second shaft 16 is interposed between the ring gear 32 of the set 28 and the transmission housing 42, and the third brake 16 is connected to the planet carrier 34 of the first simple planetary gear set 28. 26) and the transmission housing 42 to allow the elements to act as selective reaction elements. The ring gear 44 of the second simple planetary gear set 30 has an output gear 46 at its distal end. Can be mounted to act as an output element

In the above, the first and second clutches 8 and 10 forming the clutch means may be a multi-plate clutch, and the first, second and third brakes 12, 14 and 16 forming the brake means are conventional. Band brakes can be used.

As described above, the gear train of the present invention is shifted while the friction element is operated as in the friction element operation table of FIG. 2, and the shifting process is explained by looking at the operation element table and the lever analysis table of FIG. 3. .

First, in order to interpret the composite planetary gear set in the lever method, the first node N1 on the lever L is the sun gear 40 of the first simple planetary gear set 28, and the second node N2 is the second. The ring gear 44 of the simple planetary gear set 30, the third node N3 are the first and second planetary carriers 34 and 36 of the planetary gear set 28, and the fourth node N4 is the first. It is assumed that the single gear planetary gear set 28 is set to the ring gear 32.

The element for the node is set by a combination of the composite planetary gear set, and the related art is known, and thus detailed description thereof will be omitted.

In consideration of this point, an operation process of the first forward speed will be described. In the first speed, the first clutch 8 and the first brake 12 are operated and controlled.

Then, the power of the input shaft 24 rotated by the engine 2 causes the ring gear 32 of the first simple planetary gear set 28 to act as an input element by the operation of the first clutch 8. As the ring gear 40 of the second simple planetary gear set 28 acts as a reaction force element by the operation of the first brake 12, a first speed shift is performed and an output element of the second simple planetary gear set 30 is used. The output is made through the ring gear 44.

Looking at this shifting process visually while looking at FIG. 3, a straight line L1 connecting the first input speed line S1 input to the fourth node N4 and the first node N1 acting as a reaction force element. Is connected to the second node (N2) as the output element closest to the output speed line (D1) of the first speed.

That is, it can be seen that the output rotation speed becomes much smaller than the input rotation speed, so that the deceleration is performed at the speed ratio of the first speed.

When the vehicle speed and the throttle opening degree increase in the state of the first speed as described above, the operation of the first clutch 8 is released and the second clutch 10 is operated in the transformer control unit.

The operation of the second clutch 10 in the state of the input such as the first speed converts the input element into the planetary carrier 34 of the first simple planetary gear set 28 to thereby perform the second speed shift.

In this case, both planet carriers 34 and 36 are connected to each other, and are interlocked together to become input elements.

Looking at the second speed shift process while visually looking at FIG. 3, a straight line L2 connecting the second input speed line S2 of the third node N3 and the fourth node N4 acting as a reaction force element. ) Is connected to the second node (N2) as the output element closest to the output speed line (D2) of the second speed, the output is made faster than the first speed.

When the vehicle speed and the throttle opening degree are increased in the state of the second speed as described above, the transmission control unit releases the operation of the first brake 12 and operates the first clutch 8.

Then, the second input is made according to the operation of the first clutch 8 in the state of the input of the second speed, and thus the two input elements are provided. Therefore, the speed of the third speed is achieved while being directly connected to the planetary gear set. You lose.

Referring to FIG. 3, the third speed shift process is performed by visually looking at a third diagram. The first input speed line S1 input to the fourth node N4 and the third node N2 acting as another input element are described. The line connecting the straight line L3 connecting the two input speed lines S2 to the second node N2 which is the output element most closely becomes the output speed line D3 of the third speed.

When the vehicle speed and the throttle opening degree are further increased in the state of the third speed as described above, the transmission control unit releases the operation of the first clutch 8 operated at the third speed, and controls the second brake 14 to operate. Done.

Then, the first input is released, and the fourth gear is made while the ring gear 32 of the first simple planetary gear set 28 acts as a reaction force element by the operation of the second brake 44.

Looking at the speed shift process of the fourth speed visually looking at Figure 3, the straight line (L4) connecting the second input speed line (S2) of the third node (N3) and the fourth node (N4) acting as a reaction element ) Is connected to the second node (N2) as the output element is the output speed line (D4) of the fourth speed.

That is, the fourth speed is in an overdrive state in which output is performed faster than the input speed.

When the driver changes the selector lever to the reverse range R for reversing, the trans control unit operates to control the first clutch 8 and the third brake 16.

Then, the input is made through the ring gear 32 of the first simple planetary gear set 28 by the operation of the first clutch 8, and at the same time, the second simple planetary gear set by the operation of the third brake 16. As the planetary carrier 40 of 30 acts as a reaction force element, the reverse shift is made and output through the ring gear 44 of the second simple planetary gear set 30 that is the output element.

That is, as shown in FIG. 3, a second straight line L5 connecting the first input speed line S1 of the fourth node N4 and the third node N3 acting as a reaction element is the second output element. The line connecting to the node N2 becomes the reverse output speed line (R).

As described above, according to the present invention, by applying a compound planetary gear set that is combined in a radial direction, it is possible to design an automatic transmission having a very short length, so that the invention is very easy to apply to the transverse front wheel drive vehicle.

Claims (4)

The second simple planetary gear set is surrounded by the outer ring gear of the first simple planetary gear set so that the ring gear of the first simple planetary gear set can act as the sun gear of the second simple planetary gear set. The planetary carriers of a simple planetary gear set are interconnected to act as input and reaction elements, retaining four operating elements, of which at least two elements are selected and set as input elements and reaction elements at each shift stage. A composite planetary gear set for shifting; Clutch means for actuating such that the ring gear of the first simple planetary gear set and the planetary carrier of the first simple planetary gear set are selectively input elements; A sun gear and a ring gear of said first simple planetary gear set, and brake means for actuating each planetary carrier selectively to be a reaction element; Gear train of a four-speed automatic transmission for a vehicle comprising a. 2. The clutch of claim 1, wherein the clutch means for transmitting power of the engine to the composite planetary gear set comprises: a first clutch interposed between the ring gear and the input shaft of the first simple planetary gear set; A second clutch interposed between the planetary carrier of the first simple planetary gear set and the input shaft; Gear train of a four-speed automatic transmission for a vehicle comprising a. 2. The brake device of claim 1, wherein the brake means comprises: a first brake interposed between the sun gear of the first and second simple planetary gear sets and the transmission housing; A second brake interposed between the ring gear of the first simple planetary gear set and the transmission housing; A third brake interposed between the planetary carrier of the first simple planetary gear set and the transmission housing; Gear train of a four-speed automatic transmission for a vehicle comprising a. 2. The gear train of claim 4, wherein the clutch forming the clutch means is a multi-plate clutch, and the brake forming the brake means is a band brake.