JP2847859B2 - Automatic transmission for vehicles - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission having a configuration in which a plurality of gears are set by frictional engagement means such as a clutch and a brake.

2. Description of the Related Art As an automatic transmission for a vehicle, a plurality of sets of planetary gear mechanisms are arranged on the same axis, and the connection relationship between elements of the planetary gear mechanisms and the connection relationship with an input shaft are variously changed by a clutch. It is well known that a configuration in which a plurality of gears are set by changing various elements to be fixed by a brake is generally used. In this type of automatic transmission, the greater the number of planetary gear mechanisms to be used, and the more diverse the connection relationship between the elements via the clutch and the brake, the greater the number of shift stages that can be set. As an example, Japanese Patent Application Laid-Open No. Sho 60-57036 discloses that three sets of planetary gear mechanisms are used, and five forward speeds and one reverse speed are set as main shift speeds. An automatic transmission capable of setting two intermediate stages, that is, an intermediate stage between the third and fourth speeds, is described. Further, the automatic transmission includes first to fifth clutches and first and second brakes, and is configured to shift to the first to fifth speeds as follows. . That is, the first speed engages the four friction engagement means of the second clutch, the third clutch, the fifth clutch, and the second brake, and the shift to the second speed engages the first brake and the fifth clutch. Disengaging the clutch and shifting from the second speed to the third speed engages the first brake and releases the first clutch. Further, the shift from the third speed to the fourth speed engages the fourth and fifth clutches and releases the second brake, and the shift from the fourth speed to the fifth speed applies the first brake. The engagement is performed while the second clutch is released.

Problems to be Solved by the Invention In the above-mentioned conventional automatic transmission, a one-way clutch is arranged in parallel with a clutch or a brake to perform a smooth shift. A pressure adjusting mechanism such as an accumulator is required in order to optimize the timing of the engagement. For example, in the above-described automatic transmission, an accumulator is attached to the first brake to reduce shock when shifting from the first speed to the second speed, and to shift from the third speed to the fourth speed. In this case, in conjunction with the release of the second brake, the fifth clutch for transmitting the driving force is engaged with the member (the sun gear of the third planetary gear mechanism) fixed by the second brake. An accumulator is attached to the fifth clutch to reduce the shock. As described above, in the conventional automatic transmission, although the number of shift stages that can be set is large, the number of accumulators must be increased in addition to the number of friction engagement means for setting those shift stages. As a result, there was a problem that the size of the automatic transmission was increased as a whole.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an automatic transmission that can simplify the configuration for adjusting the hydraulic pressure and reduce the size.

Means for Solving the Problems In order to achieve the above object, the present invention provides a gear set to a plurality of gears having different gear ratios depending on the engagement / disengagement state of a plurality of friction engagement means. An automatic transmission having a gear train, wherein any one of the friction engagement means is connected to a pressure adjusting mechanism that adjusts a hydraulic pressure supplied from a switching valve to engage the friction engagement means. A plurality of combinations of engagement and disengagement patterns of the frictional engagement means are configured to be capable of setting a predetermined shift speed, and when at least two shift speeds including the predetermined shift speed are set, Engagement / disengagement of the frictional engagement means such that the hydraulic pressure is adjusted by the pressure adjusting mechanism to select one of the frictional engagement means to be engaged together. Control to select pattern It is characterized by having a device.

In the automatic transmission according to the present invention, there are a plurality of types of engagement / disengagement combination patterns of the friction engagement means for setting a predetermined shift speed, and the shift speed depends on any of the engagement / release combination patterns. Although the control device can set the shift speed determined based on the vehicle speed and the throttle opening, at least two shift speeds including a predetermined shift speed having a plurality of types of engagement / disengagement patterns of the friction engagement means. In such a case, the frictional engagement means is connected so that one of the frictional engagement means engaged together at these at least two shift speeds includes the frictional engagement means connected to the pressure adjusting mechanism. Is selected. Therefore, in the automatic transmission according to the present invention, the pressure adjusting mechanism is
When setting at least two shift speeds including a shift speed having a plurality of types of engagement / disengagement patterns of the friction engagement means, that is, since it is used at least twice,
The frequency of using the pressure adjusting mechanism increases. In other words, the number of required pressure adjusting mechanisms is smaller than the total number of combined engagement / disengagement patterns of the friction engagement means.

Embodiment Next, an embodiment of the present invention will be described in detail with reference to the drawings.

In the example shown in FIG. 1, a gear train is mainly composed of three sets of single pinion type planetary gear mechanisms 1, 2, and 3. Each element in each of these planetary gear mechanisms 1, 2, and 3 is as follows. Are connected as shown in FIG. That is, the carrier 1C of the first planetary gear mechanism 1 and the ring gear 3R of the third planetary gear mechanism 3 are connected so as to rotate integrally, and the ring gear 2R of the second planetary gear mechanism 2 and the third planetary gear mechanism 3 And the carrier 3C are connected so as to rotate integrally. The sun gear 1S of the first planetary gear mechanism 1 is connected to the carrier 2C of the second planetary gear mechanism 2 via the second clutch means K2, while the sun gear 1S of the second planetary gear mechanism 2 is connected via the fourth clutch means K4. Connected to 2S and second
The carrier 2C of the planetary gear mechanism 2 is connected to the sun gear 3S of the third planetary gear mechanism 3 via fifth clutch means K5.

In addition, as a connection structure of the above-described components, a connection structure employed in a general automatic transmission such as a hollow shaft, a solid shaft, or an appropriate connecting drum can be employed.

The input shaft 4 is connected to an engine (not shown) via a power transmission means (not shown) such as a torque converter and a fluid coupling, and the input shaft 4 and the ring gear 1R of the first planetary gear mechanism 1 are connected to each other. In between, the first to selectively connect the two
A clutch means K1 is provided, and a third clutch means K3 for selectively connecting the input shaft 4 and the sun gear 1S of the first planetary gear mechanism 1 is provided between the input means 4 and the sun gear 1S.

In practical use, each of the above clutch means K1,
~ K5 can be a multi-plate clutch, a one-way clutch or a combination thereof, and there are restrictions on the arrangement of each component, so that the connecting members for each clutch means K1, K2, K3, K4, K5 Of course, a suitable intermediate member such as a connecting drum can be interposed.

In addition, the third planetary gear mechanism 3 serves as brake means for preventing the rotation of the rotating members in the planetary gear mechanisms 1, 2, and 3 described above.
The first brake means B1 for selectively blocking the rotation of the sun gear 3S, the second brake means B2 for selectively blocking the rotation of the carrier 2C of the second planetary gear mechanism 2, and the sun gear of the second planetary gear mechanism 2 Third brake means B3 for selectively preventing rotation of 2S and fourth brake means B4 for selectively preventing rotation of sun gear 1S of first planetary gear mechanism 1 are provided. As these brake means B1, to B4, a multi-plate brake, a band brake, or a configuration in which these are combined with a one-way clutch can be adopted, and these brake means B1, to B4 and these brake means can be used. Means B1,
Needless to say, a suitable connecting member can be interposed between each element to be fixed by B4 and the transmission case (hereinafter simply referred to as a case) 6.

An output shaft 5 for transmitting rotation to a propeller shaft and a counter gear (not shown) is connected to a ring gear 2R of the second planetary gear mechanism 2 and a carrier 3C of the third planetary gear mechanism 3 connected to each other. ing.

In the automatic transmission having the configuration shown in FIG.
The first reverse speed is the main shift speed, which includes the second forward speed and the third forward speed.
So-called 2.2th, 2.5th, and 2.7th speeds are added between the first and second speeds, and so-called 3.2th and 3.5th speeds are added between the third and fourth speeds. In principle, it is possible to set 10 speeds and 1 reverse speed.
At other shift speeds except the 2.7th, 3.2th and 3.5th speeds, there are a plurality of combinations of engagement / disengagement of clutch means and brake means (so-called engagement / release patterns) for setting the shift speed. There is a set, and if this is shown as an operation table, it is as shown in Table 1. In Table 1, ○ indicates engagement, blank indicates release, and * indicates that the engagement may be performed.
No change in gear ratio or rotation state even when disengaged, such as the fifth speed clutch means K5 or the first brake means B1, the first brake means in the pattern of column b for the fourth speed
The gear ratio does not change when released, as in B1, but the rotation state changes. However, other * -marked means such as the fourth clutch means K4 and the third brake means B3 in the pattern in the column b of the second speed are used. Includes those in which the gear ratio and the rotation state do not change even if released if engaged. In Table 1, a, b, c at the second, third, fourth, fifth and reverse gears
The columns with the reference numerals indicate the engagement / release patterns of the engagement / release patterns for setting the gear stage, in which the rotation speeds of the rotating elements of the planetary gear mechanism are different. .. Represent the types of the engagement / disengagement patterns although the rotation speeds of the rotating elements of the planetary gear mechanism are not different.

Table 1 shows the gear positions that can be set in principle. In practical use, a gear position that is superior in terms of power performance and acceleration performance is selected from these gear positions. In other words, the gears whose gear ratios are close to the geometric series are selected as the main gears, and as the engagement / disengagement pattern for setting each gear. From those listed in Table 1, those that are advantageous in terms of shift controllability and durability are selected. Also, in the automatic transmission shown in FIG. 1, the setting of each speed shown in Table 1 is performed according to the engine load represented by the throttle opening and the vehicle speed, similarly to the conventional automatic transmission. As control means therefor, a hydraulic pressure control device C for supplying and discharging hydraulic pressure for engaging and disengaging the clutch means and the brake means, a vehicle speed V, a throttle opening degree θ or a shift position, a travel mode select An electronic control unit (ECU) E that outputs an electrical instruction signal to the hydraulic control device C based on input data such as a signal and oil temperature is provided.

Further, among the above frictional engagement means, the second clutch means K2
The, this accumulator 7 are attached to the pressure adjusting mechanism for adjusting the hydraulic pressure supplied to engage, and as Figure 2 when illustrate this, the shift valve (switching valve) S _V In the middle of the line pressure oil passage 8 leading to the second clutch means K2, the orifice 9 and the check ball 10
The accumulator 7 is connected via the.

The control device including the hydraulic control device C and the electronic control unit E sets the gear position based on running conditions such as the vehicle speed V and the throttle opening θ. As for the gear, a pattern for executing gear shifting by engaging frictional engagement means provided with an accumulator is selected as much as possible to set the gear.

This is specifically described as follows. First
The speeds are, for example, the patterns shown in Table 1, that is, the first clutch means K1, the fourth clutch means K4, the fifth clutch means K5,
When the first brake means B1 is engaged and set, and the shift to the second speed is determined in this state by an increase in the vehicle speed or a decrease in the throttle opening, the above-described control device performs the second control.
As the engagement / disengagement pattern for setting the speed, the pattern a- in the column of the second speed in Table 1 is selected, and the second clutch means K2
And the fourth clutch means K4 is released. Therefore, in shifting in this case, the timing of engagement of the second clutch means K2 is optimized by the accumulator 7 attached to the second clutch means K2, and shift shock is suppressed. When the shift from the second speed to the third speed is determined, the control device determines a-
And the second clutch means K2 is released and the third clutch means K3 is engaged. Further, in the case of shifting from the third speed to the fourth speed, the control device sets the a in the fourth speed column.
The pattern-is selected to engage the second clutch means K2 and release the second brake means B2. Therefore, the accumulator 7 acting upon shifting to the second speed described above also acts upon shifting to the fourth speed, thereby appropriately controlling the timing of engagement of the second clutch means K2 and generating a shift shock. To prevent Further, at the time of shifting from the fourth speed to the fifth speed, the control device selects the pattern a in the column of the fifth speed in Table 1 to release the first clutch means K1 and the third brake means B3. Is engaged.

Therefore, in the automatic transmission shown in FIG. 1, the second clutch means K2 including the accumulator is used in the case of the shift from the first speed to the second speed and the case of the shift from the third speed to the fourth speed. Since the operation is performed, the number of required accumulators may be small, and the configuration can be simplified and downsized.

In the embodiment described above, the fourth brake means B4 is not engaged when setting the forward gear, and the first brake
As shown in the table, since the fourth brake means B4 is released even in the reverse gear, the fourth brake means B4 can be omitted from the configuration shown in FIG. 1, and an example is shown in FIG.
In the configuration shown here, the fourth brake means B4 is omitted from the configuration shown in FIG. 1, and the fourth clutch means K4 is composed of a one-way clutch 20 and a multi-plate clutch 22 which are in a parallel relationship with each other. One brake means B1 comprises a one-way clutch 40 and a band brake 42 which are in a parallel relationship with each other,
Further, the second brake means B2 comprises a one-way clutch 60 and a multi-plate brake 61 which are in a parallel relationship with each other, and the third brake means B3 is a band brake. Even if the configuration shown in FIG.
A pressure adjusting mechanism such as an accumulator is attached to K2, and this is engaged at the time of shifting to the second speed and at the time of shifting to the fourth speed, thereby reducing the number of pressure adjusting mechanisms required. An automatic transmission with a simplified configuration can be obtained with a reduced number.

FIG. 4 shows still another example of the present invention. FIG. 4 is a skeleton diagram showing only the basic structure of the gear train without the control device. This gear train is different from the structure shown in FIG. 1 in that the fifth clutch means K5 is omitted and the second planetary gear mechanism 2 The ring gear 2R and the carrier 3C of the third planetary gear mechanism 3 are integrally connected, and the first brake means B1 is omitted. Although not particularly shown, a pressure adjusting mechanism such as an accumulator is additionally provided to the second clutch means K2.

An operation table of the automatic transmission having the gear train shown in FIG. 4 is shown in Table 2. As shown in Table 2, in the automatic transmission shown in FIG. 4, there are a plurality of types of engagement / disengagement patterns at the second and fourth speeds among the first to fifth speeds, which are the main shift speeds.
Therefore, in the example shown in FIG. 4, the second speed is selected and set by selecting the pattern a in the second speed column of Table 2, and the fourth speed is set to the second speed.
Control is performed so as to set in the pattern of a in the fourth speed column of the table. Therefore, even in the automatic transmission shown in FIG. 4, the case where the single accumulator is shifted to the second speed is different from the case of the automatic transmission shown in FIG.
Since the operation is performed in the case of shifting to high speed, the number of required accumulators is small, and the configuration can be simplified.

FIG. 5 is a skeleton diagram showing a gear train according to still another embodiment of the present invention. The gear train shown here is a ring gear of the second planetary gear mechanism 2 in the gear train shown in FIG.
Instead of connecting the 2R to the carrier 3C of the third planetary gear mechanism 3, the 2R is connected to a ring gear 3R, and the other configuration is the same as the configuration shown in FIG. The operation table of the automatic transmission shown in FIG. 5 is as shown in Table 3. In both the case where the second speed is set and the case where the fourth speed is set, the second clutch means K2 can be engaged. Since a pressure adjusting mechanism such as an accumulator is attached to the second clutch means K2 in the same manner as in the above-described embodiments, the pressure adjusting mechanism can be used for two types of shifts. The number of pressure adjusting mechanisms to be used can be reduced to simplify the configuration.

The configuration shown in FIG. 5 is similar to the configuration shown in FIG. 1 except that the fourth clutch means K4 is eliminated and the predetermined frictional engagement means is configured to include a one-way clutch. It can be suitable for
Even in such a case, it is possible to use a pressure adjusting mechanism such as an accumulator a plurality of times by selecting an engagement / disengagement pattern in the same manner as in the above-described speed change control, thereby simplifying the configuration. be able to.

Further, in each of the above-described embodiments, the example in which the accumulator is used as the pressure adjusting mechanism has been described. However, the present invention is not limited to each of the above-described embodiments. The present invention can also be applied to an automatic transmission employing a duty solenoid valve, an electromagnetic proportional valve, or a configuration combining these with an accumulator.

Further, the present invention can be applied to an automatic transmission having a plurality of types of combination patterns of engagement and disengagement of friction engagement means for setting a predetermined gear position. For example, Japanese Patent Application No. 1-185151, Japanese Patent Application No. 1-185152, Japanese Patent Application No. 1-18
6991, Japanese Patent Application No. 1-186992, Japanese Patent Application No. 1-205478, Japanese Patent Application No.
An automatic transmission having each configuration described in the specification and drawings such as No. 1-280957 can be mentioned.

Effect of the Invention As described above, in the automatic transmission according to the present invention, the friction engaged together when at least two gears including at least two gears are set in the engagement / release pattern of the friction engagement means. A combination pattern of engagement / disengagement of the friction engagement means is set so that any one of the engagement means selects the friction engagement means connected to the pressure adjusting mechanism.
Therefore, in the automatic transmission according to the present invention, when at least two gears including a predetermined gear having a plurality of types of engagement / disengagement patterns of the friction engagement means are set, that is, at least two times the pressure adjustment is performed. The use of the mechanism increases the frequency of use of the pressure adjustment mechanism. In other words,
Since the required number of installation patterns can be reduced with respect to the total number of engagement / release combinations of the friction engagement means, the automatic transmission can be reduced in size as a whole, and the cost can be reduced. The effect of is obtained.

[Brief description of the drawings]

FIG. 1 is a skeleton diagram showing an embodiment of the present invention in principle, FIG. 2 is a schematic diagram showing an accumulator as an example of a pressure adjusting mechanism, and FIGS. 3 to 5 show other examples of the present invention. It is a skeleton diagram which shows the example of the gear train in an Example. 1,2,3 ... Planetary gear mechanism, 1S, 2S, 3S ... Sun gear, 1C, 2
C, 3C Carrier, 1R, 2R, 3R Ring gear, 4 Input shaft, 5 Output shaft, 7 Accumulator, C
Hydraulic control unit, E ... Electronic control unit, _SV ...
... Shift valve.

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Claims (1)

(57) [Claims] A gear train which is set to a plurality of gears having different speed ratios in accordance with the engagement / disengagement state of the plurality of frictional engagement means, and wherein any one of the frictional engagement means includes In an automatic transmission connected to a pressure adjusting mechanism that adjusts a hydraulic pressure supplied from a switching valve so as to engage an engaging means, the gear train includes a combination pattern of engagement and disengagement of the friction engagement means. A plurality of types of predetermined gears are configured to be able to be set, and at least one of the frictional engagement means engaged when setting at least two gears including the predetermined gear is set. And a control device for setting an engagement / disengagement pattern of the friction engagement means so that the friction engagement means to be engaged by adjusting the oil pressure by the pressure adjustment mechanism is selected. Automatic transmission for vehicles.