KR0162801B1 - The gear train of 4-speed automatic transmission for a vehicle - Google Patents

Abstract

The present invention provides a gear train of a four-speed automatic transmission for a vehicle which is capable of designing an automatic transmission having a very short total length by applying a compound planetary gear set that is combined in a radial direction, thereby making it easy to apply to a transverse front wheel drive vehicle. The second simple planetary gear set is surrounded by the 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, A set of sun gear and a ring gear of the second simple planetary gear set are interconnected and at least two elements are selected and set as an input element and a reaction element at each gear of the operating elements, A fourth planetary gear set capable of achieving a speed change stage of the first forward speed and the reverse speed by the first planetary gear set; Gear transmission means interposed between the three elements of the complex planetary gear set and the input shaft to transmit power; Clutch means operable to selectively engage the ring gear of the first simple planetary gear set, the planetary carrier of the first simple planetary gear set, the sun gear of the first and second simple planetary gear sets and the ring gear; Braking means operable such that the planetary carrier of the first simple planetary gear set and the ring gear of the second simple planetary gear set are each selectively a reaction force element; Speed automatic transmission according to the present invention.

Description

Gear trains for 4-speed automatic transmissions for vehicles

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

FIG. 2 is a diagram for explaining the operational explanation of the present invention with a lever analysis method; FIG.

3 is an operation table of the frictional element for each shift stage for obtaining the gear ratios of the fourth forward gear and the reverse reverse gear of the second gear train.

The present invention relates to a gear train of a 4-speed automatic transmission for a vehicle, and more particularly, it is possible to design an automatic transmission having a very short overall length by applying a compound planetary gear set that is combined in a radial direction, To a gear train of a four-speed automatic transmission for a vehicle.

BACKGROUND ART [0002] In general, a vehicular automatic transmission includes a transmission control unit for automatically controlling a speed ratio in accordance with a running speed of a vehicle and a variation in load.

The transmission control unit controls the plurality of friction elements installed on the gear train to be in an operating state or in a non-operating state to select one of three elements (sun gear, ring gear, and planet carrier) of the planetary gear set as an input element, And the output stage revolution is controlled by selecting the reaction force element.

A compound planetary gear device used in such an automatic transmission for a vehicle includes a rabbit type, a simpson type, and a two-type planetary gear type.

In order to be used as a transmission means of a vehicle, the above-mentioned compound planetary gear device has a structure in which planetary carriers are connected to each other or has a structure in which a sun gear is shared and a planetary carrier and a ring gear are directly connected, or a planetary carrier and a ring gear That is, a structure in which two planetary gear sets are axially connected.

Accordingly, since the length of the transmission in the axial direction becomes long and the overall length of the transmission becomes long, particularly in the case of the transverse front wheel drive type automatic transmission, it is very disadvantageous in terms of the mounting performance.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide an automatic transmission having a very short overall length by applying a set of compound radial gears The present invention provides a gear train of a four-speed automatic transmission for a vehicle.

In order to achieve the above object, the present invention is characterized in that a second simple planetary gear set is surrounded on the outside of the ring gear of the first simple planetary gear set so that the ring gear of the first simple planetary gear set is engaged with the sun gear of the second simple planetary gear set Wherein the first simple planetary gear set has four working elements by interconnecting the sun gear of the first simple planetary gear set and the ring gear of the second simple planetary gear set and at least two elements at each of the first and second simple planetary gear sets, A compound planetary gear set capable of selecting a forward reaction force element and obtaining a forward speed range of a forward speed and a reverse speed by complementary action; Gear transmission means interposed between the three elements of the complex planetary gear set and the input shaft to transmit power; Clutch means operable to selectively engage the ring gear of the first simple planetary gear set, the planetary carrier of the first simple planetary gear set, the sun gear of the first and second simple planetary gear sets and the ring gear; Braking means operable such that the planetary carrier of the first simple planetary gear set and the ring gear of the second simple planetary gear set are each selectively a reaction force element; Speed automatic transmission according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a diagram showing a gear train of an embodiment according to the present invention. The power generated from the engine 2 is torque-converted through the torque converter 4 and input to the complex planetary gear set 6, do.

Wherein the compound planetary gear set 6 is input to at least one element in a selective operation of the clutch means consisting of a plurality of clutches 8, 10 and 12 and the plurality of brakes 14, , At least one element acts as a reaction force element in all the operation regions except for the third forward speed, so that the shifting is performed.

The torque converter 4 for converting the torque generated from the engine 2 is provided with a pump impeller 18 rotating directly on the crankshaft of the engine 2 and an oil And a stator 22 disposed between the pump impeller 18 and the turbine runner 20 to change the flow of the oil to increase the rotational force of the pump impeller 18. The turbine runner 20 rotates together with the turbine runner 20, .

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 2 and then flow into the stator 22 .

The oil introduced into the stator 22 is changed in direction and then flows into the pump impeller 18 again. At this time, the turbine runner 20, which is shared by the stator 22 by the rotation of the stator 22 And the rotational force of the pump impeller 18, so that torque conversion is performed.

The complex planetary gear set 6 that receives power from the torque converter 4 is connected to a turbine runner 20 of the torque converter 4 via a second shaft (Not shown).

The complex planetary gear set 6 consists of a first and a second simple planetary gear set 28 and 30 which are combined in the radial direction and which are arranged 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 also act as the sun gear of the second simple planetary gear set 30.

The sun gear 34 of the first and second simple planetary gear sets 28 and 30 and the ring gear 36 are connected to the planetary carrier 38 of the first simple planetary gear set 28 and the ring gear 32 ) And the planetary carrier 40 of the second simple planetary gear set 30 to have four operating elements.

The ring gear 32 of the first simple planetary gear set 28 and the planet carrier 38 are connected to the input shaft 24 through the first gear 42 and the first simple planetary gear set 28 The sun gear 34 of the second simple planetary gear set 30 and the ring gear 36 of the second simple planetary gear set 30 are connected to the input shaft 24 by the second gear 44 to transmit power. And the clutch hook is formed by using the clutch hook to improve the fabrication and assembling property in structure, and is configured to be able to transmit the power by the internal gear method.

The first clutch 8 serving as the clutch means for transmitting the power of the engine 2 to the aforementioned complex planetary gear set 6 is constituted by the first gear 42 and the ring gear of the first simple planetary gear set 28, The second clutch 10 is interposed between the first gear 42 and the planetary carrier 38 of the first simple planetary gear set 30 and the third clutch 10 is interposed between the second planetary gear 32 and the input shaft 24, The clutch 12 is interposed between the second gear 44 and the ring gear 36 of the second simple planetary gear set 30. [

So that the elements connected thereto by the selective operation of the clutches 8, 10 and 12 are optional or the two elements act simultaneously as input elements.

The third clutch 12 is interposed between the second gear 44 and the ring gear of the simple planetary gear set 30. The ring gear 36 of the third clutch 12 is connected to the sun gear of the first simple planetary gear set 28, And the power transmitted to the sun gear 34 can be interrupted.

The first brake 14 forming the brake means is interposed between the planetary carrier 38 of the first simple planetary gear set 28 and the transmission housing 46 and the second brake 16 is interposed between the planetary carrier 38 of the first simple planetary gear set 28 and the second simple planetary gear set 28. [ The planetary carrier 40 of the second simple planetary gear set 30 is disposed between the ring gear 36 of the gear set 30 and the transmission housing 46 so that the elements can selectively act as reaction elements, And an output gear 48 mounted at its distal end to act as an output element.

The first, second and third clutches 8, 10 and 12, which constitute the clutch means in the above, can be used as multi-plate clutches and the first and second brakes 14 and 16, which form the brake means, Brake can be used.

The gear train of the present invention having the above-described structure will now be described with reference to the table of the operating elements and the lever analysis table of FIG. 3 in which the shifting is performed while the friction elements are operated as shown in the friction element operation table of FIG. 2 .

The first node N1 on the lever L is connected to the sun gear 34 of the simple planetary gear set 28 and the ring of the second simple planetary gear set 30, The third node N3 is connected to the planetary carrier 40 of the second simple planetary gear set 30 and the second node N2 is connected to the planetary carrier 38 of the first simple planetary gear set 28, , And the fourth node N4 is set to the ring gear 32 of the first simple planetary gear set 28. [

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

Taking this into consideration, the operation of the forward first speed will be described. In the first speed, the first clutch 8 and the first brake 14 are controlled in operation.

Then the power of the input shaft 24 rotated by the engine 2 is transmitted to the ring gear 32 of the first simple planetary gear set 28 by the operation of the first clutch 8 as an input element, The operation of the first brake 14 causes the first planetary gear shift to be performed while the planetary carrier 38 of the first simple planetary gear set 28 acts as the reaction force element to generate the output of the second simple planetary gear set 30 The output is made through the planetary carrier 40. [

3, a straight line L1 connecting a first input speed line S1 input to the fourth node N4 and a second node N2 acting as a reaction force element is connected to an output element The line closest to the third node N3 is the first-speed output speed line D1.

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 stator opening degree increase in the first-speed state as described above, the first brake 14 is deactivated and the second brake 16 is activated in the trans control unit.

The operation of the second brake 16 in the state of the input such as the first speed causes the reaction force element to be made of the ring gear 36 of the second simple planetary gear set 30,

3, a straight line L2 connecting the first input speed line S1 of the fourth node N4 and the first node N1 acting as a reaction force element is referred to as an output element The output line D2 is connected to the third node N3, which is the closest to the third node N3, and the output is faster than the first speed.

When the vehicle speed and throttle opening degree are increased in the state of the second speed as described above, the transmission control unit releases the operation of the second brake 16 and operates the second clutch 10.

Since the second input is performed in accordance with the operation of the second clutch 10 in the state of the input of the second speed and the input is provided by the two input elements, the shifting of the third speed is achieved do.

Referring to FIG. 3, the third input speed line S1 is input to the fourth node N4, and the second input speed line N2 of the second node N2, which is another input element, The line connecting the straight line L3 connecting the second node S2 to the third node N3 as the output element becomes the third output speed line D3.

When the vehicle speed and throttle opening degree further increase in the state of the third speed as described above, the transmission control unit releases the operation of the first clutch 8 operating in the third speed and controls the second brake 16. [

Then, the first input is released, and the operation of the second brake 16 causes the planetary carrier 32 of the first simple planetary gear set 28 to act as a reaction force element, thereby shifting the fourth speed.

Referring to FIG. 3, the fourth line of the speed change process is represented by a straight line L4 connecting the second input speed line S2 of the second node N2 and the first node N1 acting as a reaction force element, And the line connected to the third node N3 as the fourth output speed line becomes the fourth output speed line D4.

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

When the driver turns the selector lever to the reverse range (R) for backward movement, the trance control unit controls the operation of the third clutch 12 and the first brake 14.

The input of the sun gear 34 of the first simple planetary gear set 28 and the ring gear 36 of the second simple planetary gear set 30 is performed by the operation of the third clutch 12, 1 brake 14 causes the planetary carrier 38 of the first simple planetary gear set 28 to act as a reaction force element so that a reverse shift is performed to change the planetary carrier 38 of the second simple planetary gear set 30, (40).

That is, as shown in FIG. 3, a straight line L5 connecting the third input speed line S3 of the first node N1 and the second node N2 acting as a reaction force element is referred to as a third node And the line connecting with the output port N3 becomes the reverse output speed line R. [

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

Claims (5)

The second simple planetary gear set is surrounded by the 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, A set of sun gear and a ring gear of the second simple planetary gear set are interconnected and at least two elements are selected and set as an input element and a reaction element at each gear of the operating elements, A fourth planetary gear set capable of achieving a speed change stage of the first forward speed and the reverse speed by the first planetary gear set; Gear transmission means interposed between the three elements of the complex planetary gear set and the input shaft to transmit power; Clutch means operable to selectively engage the ring gear of the first simple planetary gear set, the planetary carrier of the first simple planetary gear set, the sun gear of the first and second simple planetary gear sets and the ring gear; Braking means operable such that the planetary carrier of the first simple planetary gear set and the ring gear of the second simple planetary gear set are each selectively a reaction force element; And a gear train of a four-speed automatic transmission for a vehicle. 2. The planetary gear set according to claim 1, wherein the gear transmission means comprises: a first gear interposed between the input shaft and a second shaft connected to the ring gear of the first simple planetary gear set and the planetary carrier; A second gear interposed between the input shaft and the ring gear of the second simple planetary gear set; And the gear train of the four-speed automatic transmission for a vehicle. 2. The planetary gear set according to claim 1, wherein the clutch means for transmitting the power of the engine to the complex planetary gear set comprises: a first clutch interposed between a first shaft and a second shaft connected to the ring gear of the first simple planetary gear set; A second clutch interposed between the first planetary carrier and the first gear of the first simple planetary gear set; A third clutch interposed between the ring gear and the second gear of the second simple planetary gear set; And a gear train of the fourth-speed automatic transmission for a vehicle. 2. The planetary gear set of claim 1, wherein the braking means comprises: a first brake interposed between the planetary carrier of the first simple planetary gear set and the transmission housing; A second brake interposed between the ring gear of the second simple planetary gear set and the transmission housing; And a gear train of the fourth-speed automatic transmission for a vehicle. A gear train of a four-speed automatic transmission for a vehicle according to claim 1, wherein the clutch forming the clutch means is a multi-plate clutch, and the brake forming the brake means is a band brake.