KR19980046726A - Power train for automatic transmission - Google Patents

Abstract

In the powertrain of an automatic transmission for a vehicle having a compound planetary gear device in which two double pinion planetary gear sets have a fixed engagement and a variable engagement structure, a turbine of a torque converter is used to minimize the frictional loss of friction elements that do not work. A double pinion planetary gear set having an input shaft that receives rotational power of the engine from the engine, the element being fixedly coupled to the input shaft, and adjusting the rotational speed of the output to the input according to the rotational power of the input shaft, the double pinion planetary gear Another double pinion planetary gear set having a structure fixedly connected to an element fixedly connected to the elements of the set and having a structure variably connected to the transmission housing and shifting according to the power transmitted from the double pinion planetary gear set, wherein Reminding the rotational power of one input shaft The action of transmitting to one of the three elements of the double pinion planetary gear set and the other of the double pinion planetary gear set, and to transmitting the power to any one of the three elements of the double pinion planetary gear set. Clutch means for one action, the action of transmitting the rotational power of the input shaft to the other double pinion planetary gear set through the double pinion planetary gear set and to any one of the three elements of the double pinion planetary gear set. When performing any one of the functions of transmitting power to one element of the other double pinion planetary gear set, one element of the double pinion planetary gear set described above and one element of the other double pinion planetary gear set are selectively connected. Automatic transmission comprising brake means for selecting the elements of the sets as reaction elements Power train.

Description

Power train for automatic transmission

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission for a vehicle, and more particularly, a power train for an automatic transmission in which four of the elements of two double pinion planetary gear sets are variably connected to minimize frictional loss of a friction element that does not operate. It is about.

BACKGROUND ART In general, an automatic transmission for a vehicle includes a transmission control unit that automatically controls a transmission ratio according to a change in a traveling speed and an engine 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 three elements of the planetary gear set (ie, input element, reaction force element, and output element) is input. And, by controlling the other element to the reaction element to adjust the number of rotation of the output stage.

At least five friction elements should be used to design a gear train that can output a gear ratio of four forward speeds and one reverse speed.

Among these friction elements, the rotation radius of the friction element used as the clutch means must be smaller than the rotation radius of the output element in order for the clutch means to be connected to the input shaft, and there is a structural constraint to be smaller than the rotation radius of the reaction force element.

In general, a compound planetary gear device has a direct structure in which at least two different elements can be used in common. This is because in the case of the four-speed automatic transmission, the planetary gear unit has four independent speeds, but the six planetary gear units using two simple planetary gear units having three independent speeds cannot obtain six independent speeds. to be.

In addition, the planetary gear device of the automatic transmission device for a vehicle is generally used in the type of planetary gear device of Lavigne type, Simpson type and two-simple type.

In order to be used as a transmission means in a vehicle, the compound planetary gear device has a structure in which the rib type shares a ring gear and connects the planetary carrier, and the Simpson type has a structure in which the planet carrier and the ring gear are connected while sharing the sun gear. The two-simple type has a structure in which a planetary carrier and a ring gear are interconnected.

Therefore, in the above-described compound planetary gear device, a friction element that does not operate at any shift stage and does not affect the shift in realizing a shift is generated, and this friction element causes friction between its drive shaft and the driven side to reduce friction loss. Will result.

Therefore, the present invention has been invented to solve the above problems, the present invention is to provide a power train for an automatic transmission that minimizes the frictional loss of the friction elements that do not operate in the clutch hook up (speed) for each shift stage. It is.

A specific object of the present invention is to fix the ring gear of the double pinion planetary gear set and the ring gear of the other double pinion planetary gear set, and to change the ring gear of the double pinion planetary gear set and the ring gear of the other double pinion planetary gear set. Friction elements at the 3rd forward speed by connecting the double pinion planetary gear set sun gear and the other double pinion gear set ring gear, and the double pinion planetary gear set sun gear and the other double pinion planetary gear set sun gear. It is to provide a power train for an automatic transmission that minimizes friction loss.

In order to realize this, the power train for an automatic transmission according to the present invention has an input shaft that receives rotational power of an engine from a turbine of a torque converter and has an input shaft that is fixedly coupled to the input shaft, and according to the rotational power of the input shaft. Double pinion planetary gear sets for regulating the number of revolutions of the output, with elements fixedly connected to the elements of this double pinion planetary gear set and variably connected to the transmission housing, and having a structure that is variably connected to the transmission housing. Another double pinion planetary gear set that shifts according to the power transmitted from the set, the action of transmitting the rotational force of the input shaft to the double pinion planetary gear set and the other double pinion planetary gear set and 3 of the double pinion planetary gear set. Power transmitted to any of the elements A clutch means for transmitting any one of the elements of the other double-pinion planetary gear set, and transmitting the rotational power of the input shaft to the double-pinion planetary gear set through the double-pinion planetary gear set; When one of the three elements of the double pinion planetary gear set transfers power to any one of the other double pinion planetary gear sets, it is different from the one of the above-mentioned double pinion planetary gear sets. And brake means for selectively connecting one element of the double pinion planetary gear set to select the element of the planetary gear sets as a reaction force element.

The sun gear of the double pinion planetary gear set is fixed to the input shaft.

The clutch means is provided between the planetary carrier of the double pinion planetary gear set and the ring gear of the other double pinion planetary gear set to clamp the power transmission, the double pinion planetary gear set and the other double pinion planetary planet. A second clutch means provided between the ring gears of the gear set to interlock power transmission, and a third clutch means installed between the sun gear of the double pinion planetary gear set and the sun gear of the other double pinion planetary gear set to interrupt power transmission. do.

The brake means is provided between the ring gear of the other double pinion planetary gear set and the transmission housing to interlock power transmission, and is installed between the sun gear and the transmission housing of the other double pinion planetary gear set to interrupt power transmission. A second brake means.

In addition, the ring gear of the double pinion planetary gear set and the planet carrier of the other double pinion planetary gear set are connected by a power transmission member in a fixed coupling structure.

The planetary carrier of the double pinion planetary gear set described above and the ring gear of the other double pinion planetary gear set are connected in a variable engagement structure by clutch means.

The sun gear of the double pinion planetary gear set and the ring gear of the other double pinion planetary gear set are connected in a variable engagement structure by clutch means.

The sun gear of the double pinion planetary gear set and the sun gear of the other double pinion planetary gear set are connected in a variable engagement structure by clutch means.

Hereinafter, the preferred configuration and operation of the present invention will be described in more detail with reference to the accompanying drawings.

1 is a configuration diagram of a power train for an automatic transmission according to the present invention.

1 is a configuration diagram of a power train for an automatic transmission according to the present invention, in which the rotational power of the engine E is torque-converted in the torque converter T to be transmitted to the input shaft 1 of the transmission portion.

In the above, the input shaft 1 receives torque from the turbine of the torque converter T to transmit torque to the double pinion planetary gear set 3, and the double pinion planetary gear set 3 is another double pinion planetary gear set ( 5) Clutch hook up to deliver torque.

That is, the input shaft 1 and the sun gear 7 of the double pinion planetary gear set 3 are directly connected to each other to form a structure capable of always receiving rotational power of the input shaft 1.

A first clutch means C1 is provided between the planet carrier 9 of the double pinion planetary gear set 3 and the ring gear 11 of the other double pinion planetary gear set 5, and the first clutch means (1). C1) is configured to transmit or block the rotational power of the double pinion planetary gear set 3 to the ring gear 11 of the other double pinion planetary gear set 5.

That is, the ring gear 9 of the double pinion planetary gear set 3 and the ring gear 11 of the other double pinion planetary gear set 5 are connected in a variable coupling structure.

And between the sun gear 7 of the double pinion planetary gear set 3 and the ring gear 11 of the other double pinion planetary gear set 5 so that the double pinion planetary gear set 3 can have two input elements. Two clutch means (C2) are provided, the second clutch means (C2) is a ring gear (11) of the double pinion planetary gear set (5), the rotational power of the double pinion planetary gear set (3) sun gear (7) It is made of a structure that can be delivered or blocked.

That is, the sun gear 7 of the double pinion planetary gear set 3 and the ring gear 11 of the other double pinion planetary gear set 5 are connected in a variable coupling structure.

A third clutch means C3 is provided between the sun gear 7 of the double pinion planetary gear set 3 directly connected to the input shaft 1 and the sun gear 13 of the other double pinion planetary gear set 5. The third clutch means C3 is configured to transmit or block the rotational power of the input shaft 1 to the sun gear 13 of the other double pinion planetary gear set 5.

That is, the sun gear 7 of the double pinion planetary gear set 3 and the sun gear 13 of the other double pinion planetary gear set 5 are connected in a variable coupling structure.

The above-mentioned first, second and third clutch means C1, 2 and 3 can use a multi-plate clutch generally used for the power train of the automatic transmission for a vehicle.

On the other hand, brake means are provided for fixing one element of the planetary gear sets to act as a reaction force element so that the planetary gear set can adjust the output rotation speed with respect to the input when one or more clutch means are operated.

That is, a first brake means B1 is provided between the ring gear 11 of the other double pinion planetary gear set 5 and the transmission housing 15, and the first brake means B1 is a planetary gear set (1). The ring gear 11 of 5) is configured to be fixed or to rotate independently.

A second brake means B2 is installed between the sun gear 13 and the transmission housing 15 of the other double pinion planetary gear set 5, and the second brake means B2 is provided with another double pinion planetary gear set (2). 5) the sun gear 13 is made of a structure that can be fixed or rotate independently.

In addition, the planetary carrier 17 of the other double pinion planetary gear set 5 and the ring gear 19 of the double pinion planetary gear set 3 are connected in a fixed coupling structure by the power transmission member 21.

Meanwhile, a transfer drive gear integrally formed with the planet carrier 17 of the other double pinion planetary gear set 5 directly connected to the ring gear 19 of the double pinion planetary gear set 3 by the power transmission member 21 ( 23) is geared with a transfer driven gear (not shown) to transfer power to the differential through the final reduction gear, in this configuration, such a structure may be known, and any structure may be used. It was omitted because the intended purpose can be realized.

The power train for the automatic transmission according to the present invention made as described above has three elements of a planetary gear set (sun gear, planet carrier) according to friction elements (clutch means, brake means) selectively activated or deactivated by the transmission control unit. And one of the elements as the input element and the other element as the reaction force element, and outputs the speed ratio of the fourth forward speed and the first reverse speed, which will be described later.

The transmission control unit activates or deactivates the friction element as shown in [Table 1].

TABLE 1

Friction element operating table for each gear

When the shift lever (not shown) is selected as the forward D range and the opening amount of the throttle valve is increased, the transmission control unit causes the first clutch means C1 and the first brake means so that the gear train can output the first speed ratio. Hydraulic pressure is supplied to B1 to operate these clutches and brakes.

Hereinafter, the clutch means and the brake means to operate means that the hydraulic pressure is supplied from the hydraulic control system.

When the first clutch means C1 and the first brake means B1 are operated, the ring gear of the double pinion planetary gear set 5 different from the planet carrier 9 of the double pinion planetary gear set 3 is operated. 11 are coupled to each other and fixed to the transmission housing 15 to act as a reaction force element.

Therefore, the rotational power of the input shaft 1 is transmitted to the sun gear 7 of the double pinion planetary gear set 3, which is the input element, and rotates forward. The planetary carrier 9 acts as a reaction element, so the double pinion planetary gear set ( 3) the forward drive gear 23 integrally formed by forward rotation of the ring gear 19 of FIG. 3 and forward rotation of the planet carrier 17 of the other double pinion planetary gear set 5 connected to the power transmission member 21. FIG. Will output the gear ratio of 1 speed.

When the vehicle speed increases in the first speed state, the transmission control unit deactivates the first clutch means B1 and operates the second brake means B2 while the first clutch means C1 is operated.

By the above operation, the input element is the same as the first speed, but the reaction force element is changed from the ring gear 9 of the double pinion planetary gear set 3 to the sun gear 13 of the other double pinion planetary gear set 5, The rotational power transmitted to the sun gear 7 of the double pinion planetary gear set 3 directly connected to the input shaft 1 is transmitted through the ring gear 19 to another double pinion planetary gear set directly connected to the power transmission member 21. It is transmitted to the ring gear 17 of 5).

At this time, the pinion gear 12 installed on the planet carrier 11 of the other double pinion planetary gear set 5 rotates the outer circumference thereof by the reaction force of the sun gear 13, further rotating the planet carrier 17 by this rotation part, As the pinion gear 10 installed in the planetary carrier 9 of the double pinion planetary gear set 3 rotates, the planetary carrier 9 is further rotated by this rotation to output the second speed ratio.

When the vehicle speed increases in the second speed state, the transmission control unit deactivates the second brake means B2 and operates the second clutch means C2 while the first clutch means C1 is operated.

Since the sun gear 7 and the planet carrier 9 of the double pinion planetary gear set 3 act as input elements at the same time, the planet gear set 3 rotates integrally.

Therefore, rotational power is transmitted to the ring gear 17 of the other double pinion planetary gear set 5 directly connected to the ring gear 19 of the double pinion planetary gear set 3 as the power transmission member 21, and at the same time, these ring gears. The transmission power of the input shaft 1 is transmitted as it is through the transfer drive gear 23 integrally formed at the 19 and the planet carrier 17, thereby outputting a speed ratio of three speeds.

Furthermore, since the double pinion planetary gear set 3 rotates integrally, the ring gear 11 and the planet carrier 17 of the other double pinion planetary gear set 5 act as input elements at the same time. Therefore, the other double pinion planetary gear set 5 also rotates integrally with the double pinion planetary gear set 3.

When the vehicle speed is increased in the third speed state, the transmission control unit deactivates the first clutch means C1 and operates the second brake means B2 while the second clutch means C2 is operated.

The ring gear 11 of the other double pinion planetary gear set 5 acts as an input element by the above-described action, and the sun gear 13 acts as a reaction force element by the second brake means B2. In the pinion planetary gear set (5), the speed is increased to output a gear ratio of four speeds to the transfer drive gear (23) integrally formed on the ring gear (17).

On the other hand, when the shift lever is moved to the reverse R range, the transmission control unit operates the third clutch means C3 and the first brake means B1.

By the above operation, the sun gear 13 of the other double pinion planetary gear set 5 acts as an input element, and the ring gear 11 is fixed to the transmission housing 15 by the first brake means B1. Since the planetary carrier 17 acts as a reaction force element, the planetary carrier 17 outputs a shift ratio of reversing to the transfer drive gear 23 integrally formed therewith while rotating in reverse.

As described above, the power train for the automatic transmission according to the present invention may provide four forward shift stages and one reverse stage, in which the double pinion planetary gear set and the other double pinion planetary gear set are rotated integrally at three forward speeds. Since the slip of the friction element that does not work can be reduced, the friction loss due to the slip of the friction element can be minimized.

Claims (8)

A double pinion planetary gear set having an input shaft that receives rotational power of an engine from a turbine of a torque converter, the input shaft being fixedly coupled to the input shaft, and adjusting the rotational speed of the output to the input according to the rotational power of the input shaft, Another double pinion planetary gear having an element fixedly connected to an element of the double pinion planetary gear set and a variable connection element to the transmission housing and shifting according to the power transmitted from the double pinion planetary gear set. Gear set, the action of transmitting the rotational power of the input shaft to the double pinion planetary gear set and the other double pinion planetary gear set and the power transmitted to any one of the three elements of the double pinion planetary gear set and the other double pinion planetary To any element of the gear set Clutch means which performs any one of the actions, which transmits the rotational power of the input shaft to another double pinion planetary gear set through the double pinion planetary gear set, and any one of three elements of the double pinion planetary gear set. When one of the functions of transmitting the transmitted power to one element of the other double pinion planetary gear set, selectively connects one element of the double pinion planetary gear set and another element of the other double pinion planetary gear set A power train for an automatic transmission comprising brake means for selecting an element of the planetary gear sets as a reaction element. 2. The power train of claim 1, wherein the sun gear of the double pinion planetary gear set is fixed to the input shaft. 2. The clutch means according to claim 1, wherein the clutch means is provided between the planetary carrier of the double pinion planetary gear set and the ring gear of the other double pinion planetary gear set to interrupt power transmission, and the sun gear of the double pinion planetary gear set described above. And second clutch means installed between the ring gear of the other double-pinion planetary gear set to control power transmission, and installed between the sun gear of the double pinion planetary gear set and the sun gear of the other double pinion planetary gear set to control power transmission. Power train for automatic transmission comprising three clutch means. 2. The brake device according to claim 1, wherein the brake means is provided between the ring gear of the other double pinion planetary gear set and the transmission housing to interlock power transmission, the sun brake of the other double pinion planetary gear set and the transmission housing. A power train for an automatic transmission comprising a second brake means for interrupting power transmission. The power train for an automatic transmission according to claim 1, wherein the ring gear of the double pinion planetary gear set and the planet carrier of the other double pinion planetary gear set are connected in a fixed coupling structure by a power transmission member. The power train for an automatic transmission according to claim 1, wherein the planetary carrier of the double pinion planetary gear set and the ring gear of the double pinion planetary gear set are connected in a variable coupling structure by clutch means. The power train for an automatic transmission according to claim 1, wherein the sun gear of the double pinion planetary gear set and the ring gear of the other double pinion planetary gear set are connected in a variable coupling structure by clutch means. The power train for an automatic transmission according to claim 1, wherein the sun gear of the double pinion planetary gear set and the sun gear of the other double pinion planetary gear set are connected in a variable coupling structure by clutch means.