JPH05106726A - Speed shift pattern changeover device for automatic transmission - Google Patents

Abstract

PURPOSE:To provide the speed shift pattern changeover device of an automatic transmission which can change the kind of a shift pattern over to plural kinds without changing shift timing at the time of a throttle being closed fully and being opened fully. CONSTITUTION:At a throttle valve 13, apart from a port 13f to output throttle pressure, a kick down port 13j to output kick down pressure whose pressure is the same with that of throttle pressure at more than a fixed throttle opening, is provided, and at a shift valve, apart from a port through which throttle pressure is inputted, an auxiliary port through which oil pressure is inputted in the same direction with that of throttle pressure, is provided. A changeover valve 40 to lead kick down pressure or throttle pressure selectively to the auxiliary port of the shift valve, is provided between the throttle valve and the shift valve.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift pattern switching device capable of switching a shift pattern of an automatic transmission into a plurality of types.

[0002]

2. Description of the Related Art Generally, a shift pattern in the D range of an automatic transmission is uniquely set by the relationship between the throttle opening (engine load) and the vehicle speed. This shift pattern is determined mainly with an emphasis on fuel consumption in flatland driving, and is therefore not suitable for traveling in a mountainous area with many slopes and bad roads. Therefore, for example, a shift pattern switching device has been proposed in which two types of shift patterns are provided, one for economy and one for power, and the shift pattern can be switched according to a driver's judgment.

A conventionally known shift pattern switching device is disclosed in, for example, Japanese Patent Laid-Open No. 61-130651.
A drain throttle oil passage having a solenoid valve is branched in the governor pressure oil passage from the governor valve, and it is possible to switch to a plurality of types of shift patterns by changing the governor pressure characteristics. As disclosed in the publication, there is one in which a characteristic of throttle pressure adjusted by a throttle valve is changed by a solenoid valve so that a shift pattern can be switched.

[0004]

However, when the characteristics of the governor pressure and the throttle pressure are changed as described above, not only the shift pattern but also the shift timing when the throttle is fully closed and when the throttle is fully opened is changed. Could be extremely deteriorated, or the engine might overspeed. In other words, the shift tamming when the throttle is fully closed and when the throttle is fully opened is peculiar to the engine of the vehicle, and changing such a shift timing hinders matching with the engine, which is not preferable. Therefore, an object of the present invention is to provide a shift pattern switching device for an automatic transmission that can switch a shift pattern to a plurality of types without changing the shift timing when the throttle is fully closed and when the throttle is fully opened.

[0005]

To achieve the above object, the present invention provides a governor pressure P _G regulated by a governor valve.
And the throttle pressure P _T regulated by the throttle valve in the opposite direction to the shift valve, and the shift valve is operated by the load difference due to these hydraulic pressures to switch the shift speed. Apart from the port that outputs the throttle pressure P _T is the constant kickdown port for outputting the kickdown pressure P _K of the throttle pressure P _T and the pressure in the throttle opening degree or more is provided, the shift valve is a throttle pressure P _{In addition} to the port to which _T is input, an auxiliary port to which hydraulic pressure is input in the same direction as the throttle pressure P _T is provided, and a kick down pressure P _K or throttle pressure P _T is provided between the throttle valve and the shift valve. Is provided with a switching valve that is switched in conjunction with a manual operation to selectively guide the shift valve to the auxiliary port of the shift valve. .

[0006]

[Function] When driving with emphasis on fuel efficiency, the switching valve is set to, for example, the economy position, and the kickdown pressure is output from the kickdown port of the throttle valve to the auxiliary port of the shift valve through the switching valve only during kickdown. .. On the other hand, when traveling with emphasis on power performance, the switching valve is switched to, for example, the power position, and the throttle pressure is output to the shift valve via the switching valve. In this state, the throttle pressure is input to the auxiliary port of the shift valve even when the engine is not kicking down, so that the engine speed is maintained at a high value and the shift pattern can be changed to a pattern having excellent power performance. When changing the shift pattern as described above, the characteristics of the throttle pressure itself are not changed,
Since only the way in which the throttle pressure acts on the shift valve is changed, the gear change timings when the throttle is fully closed and fully opened do not change. That is, matching with the engine of the vehicle is not hindered.

The switching valve used in the present invention includes:
For example, a three-way valve type solenoid valve that switches the oil passage by a switch operation, a combination of a solenoid valve that generates a signal oil pressure by turning the switch operation ON / OFF and a spool valve that is switched by the signal oil pressure of this solenoid valve, or a manual operation A manual valve that can be directly switched by force can be considered.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an example of the present invention.
1 shows a power transmission mechanism and a hydraulic circuit of an automatic transmission having a high speed shift stage. The power transmission mechanism of this automatic transmission includes an input shaft 2 driven by an engine via a torque converter 1, two clutches C ₁ and C ₂ , and two brakes b ₁ and B ₂ and b _1. It is provided with a servo piston 3 for engaging and releasing a brake, a Ravigneaux type planetary gear mechanism 4, a one-way clutch OWC, and an output gear 5.

The reverse sun gear 4a of the planetary gear mechanism 4 is C
₁ is coupled to the input shaft 2 via a clutch, a forward sun gear 4b is coupled to the input shaft 2 via the intermediate shaft 6 and C ₂ clutch. The carrier 4c is connected to the case 7 via a B ₂ brake and a one-way clutch OWC. The one-way clutch OWC is a carrier
Only 4c forward rotation (engine rotation direction) is allowed. The carrier 4c supports a long pinion gear 4d and a short pinion gear (not shown), the reverse sun gear 4a meshes with the long pinion gear 4d having a long shaft length, and the forward sun gear 4b has a long pinion gear via a short pinion gear having a short shaft length. It meshes with the pinion gear 4d. The ring gear 4f, which meshes only with the long pinion gear 4d, is connected to the output gear 5. The power transmission mechanism realizes the gear stages shown in Table 1 by operating the clutches C ₁ , C ₂ , the brakes b ₁ , B ₂ and the one-way clutch OWC. In Table 1, ◯ indicates the operating state.

[0010]

[Table 1]

In Table 1, B ₁ is an engagement side oil chamber of the servo piston 3 and B ₁ 'is a release side oil chamber of the servo piston 3, and hydraulic pressure is introduced to both oil chambers B ₁ and B ₁ '. When the brake is applied (at the 3rd speed), the pressure receiving area of the disengagement side oil chamber B ₁ 'is large, so that the b ₁ brake is always released. In the first speed of the D and 2 ranges, the engine brake does not operate due to the one-way clutch OWC, and the B ₂ brake is engaged only in the first speed of the L range, so the engine brake can be operated. ..

The hydraulic circuit is generally composed of an oil pump 10, a regulator valve 11, a manual valve 12, a throttle valve 13, a governor valve 14, 1-2 shift valves 15, 2-3.
Shift valve 16, 3-2 Timing valve 17, Relief valve 18, C ₁ clutch accumulator 19, C ₂ clutch accumulator 20, b ₁ brake accumulator
It is composed of 21 mag. In the hydraulic circuit, the hydraulic pressure of each oil passage is as follows. That is, P _L is the line pressure, P
_R is the line pressure when retreating, P _T is the throttle pressure, P _K is the kickdown pressure, P _G is the governor pressure, P _C1 is the C ₁ clutch pressure, P _C2 is the C ₂ clutch pressure, and P _B1 is the b ₁ brake engagement. Pressure, P _{B1 ′} is the b ₁ brake release pressure, and P _B2 is the B ₂ brake pressure.

The regulator valve 11 is a valve for adjusting the discharge pressure of the oil pump 10 to a desired line pressure P _L. The discharge pressure of the oil pump 10 is input to the central port 11a and is formed inside the spool 11b. Due to the hydraulic pressure in the right end chamber 11c fed back through the communication hole, the spool 11b moves to the left against the spring 11d, and when the position shown in the figure is reached, the drain port 11e opens and the pressure oil is transferred to the oil pump. It is returned to the suction side of 10. Therefore, the spool 11b is balanced at this position and adjusted to the desired line pressure P _L. A plunger 11g is provided on the left side of the spool 11b, and the plunger 11g moves the spool 11b to the right by the throttle pressure P _T (in the D range) guided to the back pressure chamber 11h and the reverse hydraulic pressure P _R guided to the back pressure chamber 11i. Pushing. Therefore, the line pressure P _L during forward movement is as shown in FIG. 2A even when the throttle is fully closed.
Maintaining a constant hydraulic pressure that balances the spring load of 11d, it rises according to the throttle opening up to the intermediate throttle opening, and becomes almost constant when exceeding the intermediate throttle opening. In this way, the line pressure P _L is set so as to be approximately similar to the maximum engine torque at each throttle opening in order to supply a proper hydraulic pressure to each friction element.

The manual valve 12 has a spool 12a which is operated in each position of P, R, N, D, 2 and L in conjunction with a shift lever, and the total oil passage is switched by this spool 12a. It has twelve ports 12b-12m. Of these, the three ports 12b to 12d on the right side are provided on the entire circumference, and the other ports 12e to 12m constitute separate ports that are independent in the upper and lower directions in the figure. And with port 12e
12g, ports 12f and 12i, and ports 12j and 12m communicate with each other through external oil passages. The line pressure P _L is input from the regulator valve 11 to the port 12d, and the throttle pressure P _T is input to the port 12l from a throttle valve 13 described later. Then, the spool 12a is set to P, R, N,
By shifting to each position of D, 2 and L, hydraulic pressure is output from each port as shown in Table 2. In Table 2, ×
The mark indicates a drain.

[0015]

[Table 2]

The throttle valve 13 includes a plunger 13a that is pushed to the left in conjunction with the accelerator pedal, and a plunger 13a.
Spool 13c pushed to the left by spring 13b by spring 13b, and spring biasing spool 13c to the right
It has 13d. The line pressure P _L is input to the port 13e, and the throttle pressure P _T is output from the port 13f. The throttle pressure P _T is the spool 13c.
Since it is fed back to the port 13g through the communication hole, the throttle pressure P _T becomes a hydraulic pressure that increases almost linearly as the throttle opening increases as shown in FIG. 2 (b). Note that the throttle pressure P _T is also guided to the port 13i, and only when the throttle opening is opened above a certain opening such as during kickdown, the throttle pressure P _T (from the port 13i via the port 13j This is kick down pressure P _K
Is output). In other words, kick down pressure P _K
Is less than a certain opening (eg 85%) as shown in Fig. 2 (c).
Therefore, when the opening is equal to or greater than a certain degree, the pressure becomes equal to the throttle pressure P _T. The kick down pressure P _K is introduced to the 1-2 shift valve 15 and the 2-3 shift valve 16 via a three-way valve type solenoid valve 40 which is an example of a switching valve.

The governor valve 14 is driven through a governor drive gear (not shown) attached to the output shaft, regulates the line pressure P _L, and governor pressure P _G that is substantially proportional to the rotational speed of the output shaft, that is, the vehicle speed. (See FIG. 2D) is occurring. Input port from port 12e of manual valve 12
The line pressure P _L (P _C2 ) inputted to 14a is set so as to urge the governor valve 14b downward in the figure, and the centrifugal force of the governor weight 14c works in opposition thereto. As a result, the output port 14d is selectively communicated with the input port 14a or the drain port 14e, and the governor pressure P _G is adjusted to a hydraulic pressure substantially proportional to the vehicle speed. The governor pressure P _G is introduced to the 1-2 shift valve 15, the 2-3 shift valve 16 and the 3-2 timing valve 17.

The 1-2 shift valve 15 is a valve for switching between the 1st and 2nd speeds, and the right end position is the 1st speed, and when it is moved to the left, it is the 2nd speed or the 3rd speed. This valve 15
The first biased to the right (first speed side) by the spring 15a
It is equipped with a spool 15b and a second spool 15c in contact with the right end surface of the first spool 15b. The b ₁ brake engagement pressure P _B1 output from the port 15d and the B ₂ brake pressure P output from the port 15e are provided. Switching control between _B2 and. The governor pressure P _G is input to the right end port 15f, the throttle pressure P _T is always input to the port 15g, the port 15h is connected to the port 12m of the manual valve 12, and the auxiliary port 15
The kickdown pressure P _K is input to i via the three-way valve 30. Ports 15j and 15k are connected to the port 12f of the manual valve 12, and ports 15l and 15m are connected to the manual valve.
12 ports 12k connected to 15n manual valve 12
15o is connected to the port 12e of the manual valve 12 through the orifice 31. The port 15p is connected to a relief valve 18 described later and a back pressure chamber 11h of the regulator valve 11 via orifices 32 and 33. In this way, the governor pressure P _G is applied to the first spool 15b and the second spool 15c from the right side, and the spring load of the spring 15a and the throttle pressure P _T (at the first speed) and the kick are applied from the left side. By operating the down pressure P _K (at the second speed), the 1-2 speed is switched according to the magnitude relation of these loads.

The 2-3 shift valve 16 is a valve for switching the 2-3 speed, and the right end position is the 1st speed or the 2nd speed.
The third speed is reached when moving to the left. The spool 16b of the valve 16 is urged to the right by the spring 16a, and the C ₁ clutch pressure P _C1 output from the port 16c is output.
(B ₁ brake release pressure P _{B1 ′} ) is switch-controlled. The governor pressure P _G is input to the right end port 16d, and port 16e
The line pressure P _L is input to the auxiliary port 16f, and the kickdown pressure P _K is input to the auxiliary port 16f via the three-way valve 30. Also,
Port 16g is connected to the port 12b of the manual valve 12, the line pressure P _L only R-range is inputted. Port 16
h is connected to the port 12c of the manual valve 12, R,
N, the line pressure P _L is input when the D-range. Further, the throttle pressure P _T is input to the left end port 16i.
In this way, the governor pressure P is applied to the spool 16b from the right side.
_From the left, the spring load of the spring 16a, the throttle pressure P _T , the kick down pressure P _K and the line pressure (second
(Only during high speed), the 2-3 speed is switched depending on the magnitude relation of these loads.
Then, in the second speed, the port 16c is drained, so the C ₁ clutch is released, and in the third speed, the port 16c is released.
The hydraulic pressure P _C1 (same as P _{B1 '} ) is output, so C ₁
The clutch is engaged and the b ₁ brake is released.

3-2 The timing valve 17 controls the oil discharge characteristic of the b ₁ brake release pressure P _{B1 '} during the 3 → 2 shift, in other words, the b ₁ brake engagement characteristic according to the vehicle speed. This valve has a spool 17b that is biased to the left by a spring 17a and a spring at the left end port 17c.
The governor pressure P _G is input in the direction opposite to 17a.
The port 17d is connected to the release side oil chamber B ₁ 'of the servo piston 3 via the orifice 34, and the port 17e is connected to the port 16c of the 2-3 shift valve 16 without passing through the orifice. Spool 17 when shifting from 3 to 2 at low vehicle speed
Since b is at the right end position, the pressure oil in the disengagement side oil chamber B ₁ 'is drained through the parallel orifices 34 and 35, and b ₁ brake is quickly applied as the hydraulic pressure in the engagement side oil chamber B ₁ increases. It is concluded. On the other hand, when shifting from 3 to 2 at high vehicle speed, the spool
Because 17b is in the left position, pressure oil release side oil chamber B ₁ 'is drained only through the orifice 35, b ₁ brake is gently fastened. Thus, by delaying the engagement of the b ₁ brake and increasing the engine speed at high vehicle speeds, the shift shock at the time of the 3 → 2 shift is mitigated.

The relief valve 18 is a regulator valve 11
It is a valve that adjusts the hydraulic pressure in the back pressure chamber 11h of the engine, has a spool 18b biased to the left by a spring 18a, and has a 1-2 shift valve 15 in the direction opposite to the spring 18a at the left end port 18c. Throttle pressure P from port 15p
_T is being guided. When the throttle pressure P _T that is input to the left port 18c is less than the spring load of the spring 18a, the hydraulic pressure in the back pressure chamber 11h equal to the throttle pressure P _T, the throttle pressure P _T exceeds the spring load of the spring 18a Since the relief valve 18 drains, the back pressure chamber 11h
Is limited to a constant hydraulic pressure corresponding to the spring load of the spring 18a. Therefore, the line pressure P _L has the characteristic shown in FIG.

Here, the shift pattern switching device according to the present invention will be described with reference to FIG. The solenoid 40a of the solenoid valve 40 is connected to the power supply 41 via the pattern changeover switch 42. The changeover switch 42 is manually switched to two positions, economy and power, and is turned off when economy is selected and turned on when power is selected. When the changeover switch 42 is OFF (economy), the valve 40 is in the right position by the return spring 40b, and the kick down port 13j of the throttle valve 13 and the auxiliary port 15 of the shift valves 15, 16 are connected.
i, 16f are connected. Therefore, the kick down pressure P _K of FIG. 2 (c) is input to the auxiliary ports 15i and 16f, and the shift pattern has characteristics that emphasize fuel efficiency as shown by the solid line in FIG. On the other hand, when the changeover switch 42 is turned on (power), the solenoid 40a is excited and the valve 40 moves to the left, and the port 13f and the auxiliary ports 15i,
16f is connected. Therefore, the throttle pressure P _T of FIG. 2 (b) is input to the auxiliary ports 15i and 16f, and the shift pattern has a wider low speed range at the intermediate throttle opening as shown by the chain double-dashed line of FIG. Is changed to a characteristic that emphasizes. As is apparent from FIG. 4, the shift pattern can be switched in two stages by turning the solenoid valve 40 ON and OFF, but the shift timing at the time of fully closing the throttle and at the time of fully opening the throttle does not change at all. Therefore, the matching with the engine of the vehicle is not impaired, and there is no possibility of inconveniences such as deterioration of fuel consumption and engine overspeed.

FIG. 5 shows a second embodiment of the present invention. In the first embodiment, a three-way valve type solenoid valve is used as the switching valve.
Although 40 is used, in this embodiment, a solenoid valve 50 and a three-way valve 60 are combined. The solenoid valve 50 that opens and closes the drain port 51 is connected to the power source 52 via the pattern changeover switch 53. A signal port 61 connected to the drain port 51 is provided at the right end of the three-way valve 60, a port 62 to which the throttle pressure P _T is input from a throttle valve (not shown), and an auxiliary port (not shown) of the shift valve. The port 63 for outputting the hydraulic pressure to the valve) and the port 64 for inputting the kickdown pressure P _K from the throttle valve are sequentially provided. A return spring 65 is arranged at the left end of the three-way valve 60 and always urges the valve 60 to the right.
When the selector switch 53 is OFF (economy), the solenoid valve 50 closes the drain port 51 and the three-way valve.
Since the line pressure P _L is input to the signal port 61 of 60,
The 3-way valve 60 is moving to the left. Therefore, the kickdown P _K is supplied to the shift valve via the ports 64 and 63, and the shift pattern has characteristics that place importance on fuel efficiency. on the other hand,
When the changeover switch 53 is turned on (power), the solenoid valve 50 opens the drain port 51 and the signal port 61 of the three-way valve 60.
Since the hydraulic pressure is drained, the three-way valve 60 is moved to the right by the return spring 65. Therefore, the throttle pressure P _T is supplied to the shift valve via the ports 62 and 63, and the shift pattern is changed to a characteristic that emphasizes power performance.

The switching valve of the present invention is not limited to the one using the solenoid valve as in the above embodiment, but a manual valve for directly switching the oil passage by a manual operation may be used.

[0025]

As is apparent from the above description, according to the present invention, the shift pattern can be switched to a plurality of types by the switching valve, so that the shift pattern suitable for the traveling state can be selected. Moreover, since the characteristics of the throttle pressure itself are not changed, but only the kickdown pressure acting on the shift valve and the throttle pressure are switched, the gear shift timings when the throttle is fully closed and fully opened do not change,
There is no possibility of causing problems such as extreme deterioration of fuel consumption or excessive engine speed.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram of an automatic transmission according to the present invention.

2A to 2D are characteristic diagrams of line pressure, throttle pressure, kickdown pressure and governor pressure, respectively.

FIG. 3 is a hydraulic circuit diagram of the first embodiment of the present invention.

FIG. 4 is a shift diagram of the automatic transmission according to the present invention.

FIG. 5 is a hydraulic circuit diagram of a second embodiment of the present invention.

[Explanation of symbols]

 13 Throttle valve 13j Kick down port 14 Governor valve 15 1-2 Shift valve 15i Auxiliary port 16 2-3 Shift valve 16f Auxiliary port 40 Solenoid valve 42 Pattern changeover switch

Claims (1)

[Claims] 1. A governor pressure P regulated by a governor valve.
_G and throttle pressure P _T regulated by the throttle valve
In the automatic transmission in which and are input to the shift valve in the opposite direction, and the shift valve is operated by the load difference due to these hydraulic pressures to switch the shift speed, the throttle valve is provided with a port other than the port for outputting the throttle pressure P _T. , A kick down port for outputting a kick down pressure P _K equal to the throttle pressure P _T at a certain throttle opening or more is provided, and the shift valve is provided with a throttle pressure P _T in addition to a port for inputting the throttle pressure P _T. An auxiliary port to which hydraulic pressure is input in the same direction as _T is provided, and between the throttle valve and the shift valve, a kick down pressure P _K or a throttle pressure P _T is manually introduced to selectively guide it to the auxiliary port of the shift valve. A shift pattern switching device for an automatic transmission, comprising a switching valve that switches in synchronism with an operation.