JP3424517B2 - Transmission control device for automatic transmission - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission adopted in a vehicle or the like, and more particularly to an improvement of a shift control device for an automatic transmission having a manual mode in addition to an automatic shift mode.

[0002]

2. Description of the Related Art In a transmission device for an automatic transmission used in a vehicle, an automatic gear position (shift position, hereinafter the same) is determined according to operating conditions such as vehicle speed VSP and throttle opening TVO (or accelerator opening). In addition to the speed change mode, there are some known ones that have a manual mode in which an arbitrary gear stage is selected in accordance with the driver's speed change operation, as in the conventional manual transmission. As a transmission of a transmission, for example, "Diamante 95-1
"New Vehicle Manual" (published by Mitsubishi Motors Co., Ltd.), Chapter 2, p. 48, or "Automotive Engineering, October 1990"
It is known that one shift lever selectively switches between the automatic shift mode and the manual mode, such as page 38 of "Monthly Issue" (Tetsudo Nihonsha).

This is because the shift gate 92 has "P", "R", "N", "D", "2", as shown in FIG.
In addition to the automatic shift mode composed of the shift position of "1", when the shift lever 93 is moved from the "D" range to the left side in the drawing, it is switched to the manual mode. In the figure, "P", "R", "N", "D",
Automatic shift modes of "2" and "1" are parking, reverse, neutral, drive, second speed range, 1
Indicates a fixed speed range.

The shift gate 2 has a manual mode switch (not shown) for detecting that the automatic transmission mode has been switched from the D range to the manual mode, and an upshift "+" depending on the movement of the shift lever 93 in the manual mode. Alternatively, if the UP switch 94 and the DOWN switch 95 for detecting the downshift "-" are provided and the shift lever 93 is operated from the automatic shift mode "D" range to the left side in the drawing, the same operation as in the conventional manual transmission is performed. If the manual mode is entered and the shift lever 93 is stroked to the "+" side in the figure, the UP switch 94 is turned on to instruct an upshift, and similarly, if the shift lever 93 is also stroked to the "-" side. DOWN
When the switch 95 is turned on, a downshift is instructed, and the shift stage of the automatic transmission is changed relative to the current shift stage, so-called sequential shift is performed.

Further, as a shift control device for an automatic transmission, a manual valve and a solenoid valve which respond to an operating position of a shift lever are used to automatically control a shift lever, as disclosed in Japanese Patent Laid-Open No. 62-63251 proposed by the present applicant. It is known that each engagement element of a transmission is engaged and disengaged to set a shift speed according to an operating state.

This is because of the structure of the power train, 2
In the third speed and the third speed, engine braking is possible by engaging the overrun clutch, and the engine braking is appropriately applied by controlling the engagement and disengagement of the overrun clutch depending on the throttle opening degree and the like. Also, 1
At high speed, the engine brake can be activated by engaging the overrun clutch and the low and reverse brake together. However, due to the structure of the hydraulic circuit (manual valve), hydraulic pressure cannot be supplied to the low and reverse brake in the D range, and hydraulic pressure is supplied to the low and reverse brake when one range is selected with the shift lever. The engine brake works.
Therefore, the structure is such that the engine braking does not work in the first speed in the D range.

[0007]

However, in the latter conventional example, when the manual mode as shown in FIG. 7 is added, when the manual mode is selected, the shift lever is moved from the D range position in the figure. It is only displaced to the left and the position of the manual valve is D
Since the range is the same as the range, even if the driver operates the shift lever to select the first speed in the manual mode, the low and reverse brake is released. Therefore, there is a problem that the engine brake cannot be used in the first speed of the manual mode, and the driving feeling similar to that of the conventional manual transmission cannot be obtained.

Therefore, the present invention has been made in view of the above-mentioned problems. The low and reverse brake is released at the first speed in the D range, while the low and reverse brake can be engaged at the first speed in the manual mode. The purpose is to make it possible to change the driving feeling between the automatic shift mode and the manual mode.

[0009]

According to a first aspect of the present invention, an automatic shift mode and a manual mode are provided to set a shift speed in accordance with a driving state or a driving operation, and in the D range of the automatic shift mode, Shift command means that can be switched to the manual mode and switch to the manual mode
When changed, it is engaged when selecting the first speed, and is engaged at the time of shifting to the second speed with the first friction engaging element that operates the engine brake and the first friction engaging element.
Band brake, and a second frictional engagement element that operates the engine brake when engaged at the speeds higher than the second speed, and prohibits the operation of the engine brake when released, and each speed change according to the set speed. A shift control device for an automatic transmission, comprising: a shift control means for engaging and disengaging a friction engagement element preset for each stage .
For fastening the friction fastening element and the second friction fastening element
This control valve and the control valve that generates the original pressure
Source pressure generated in the second valve to the second friction engagement element
The oil passage to be supplied and the controller connected to this oil passage.
The primary pressure generated by the valve is supplied to the first friction engagement element.
Supplying oil passage and the source pressure to the first frictional engagement element
In the middle of the oil passage, the first frictional fastening element should be fastened and released.
Supplied from the control valve for switching
A shift valve for supplying or shutting off the source pressure is provided, and the shift control means controls the shift valve means so as to fasten both the first and second friction engagement elements in the first speed when the shift command means selects the manual mode. And control the shift valve ,
When the D range of the automatic speed change mode is selected, the control is performed so that the second friction engagement element is engaged according to the operating state.
Control the valve, while in the manual mode 1
When shifting from the 2nd speed to the 2nd speed,
After reducing the source pressure supplied from the
A delay drive means for permitting the fastening operation is provided .

According to a second aspect of the present invention, in the first aspect of the present invention, the shift command means includes a first speed fixed range in the automatic speed change mode, and when the first speed fixed range is selected, the speed change is performed. The control means fastens the first and second fastening elements together.

[0011]

In a third aspect based on the first aspect, the shift control means supplies the line pressure when the shift command means selects the D range or the first speed fixed range in the automatic shift mode. A forward range pressure circuit, an engine brake control valve that supplies or shuts off the hydraulic pressure of the forward range pressure circuit to the first or second friction engagement element, a solenoid valve that drives the engine brake control valve, and the shift valve. When in the 1st speed position, the solenoid valve drives the engine brake control valve to supply the hydraulic pressure of the forward line pressure circuit to the first friction engagement element.

In a fourth aspect based on the third aspect, the engine brake control valve uses the hydraulic pressure supplied when the shift command means selects the first speed fixed range in addition to the control of the solenoid valve. It is controlled to supply the hydraulic pressure of the forward line pressure circuit to the first friction engagement element.

[0014]

Therefore, according to the first aspect of the present invention, when the D range of the automatic speed change mode is selected, the second friction engagement element is released even if the first speed is selected, so that the engine brake operates. For example, while preventing a shift shock at the time of downshifting from the 2nd speed to the 1st speed and performing a smooth shift control, in the 1st speed when the manual mode is selected, both the first and second friction engagement elements are set. By concluding,
It is possible to operate the engine brake in the 1st speed and to transmit the driving force according to the driver's intention, and to reliably switch the driving feeling between the automatic speed change mode and the manual mode to change the manual mode. It is possible to improve the drivability of the provided automatic transmission. Well
In addition, when equipped with a shift valve driven according to each shift stage,
When shifting from 1st gear in manual mode to 2nd gear,
After reducing the fastening pressure of the first friction fastening element,
Since the operation of the speed valve is delayed, the interlock
To prevent shifting and to perform manual mode shifting smoothly.
it can.

The second aspect of the present invention is the automatic shift mode 1
In the fixed speed range, it is possible to operate the engine brake as in the manual mode, and it is possible to obtain a driving feeling according to the selected shift range even in the automatic shift mode.

[0016]

In the third aspect of the invention, the signal pressure of the solenoid valve is constantly applied to the engine brake control valve, so that the engine brake is prohibited from operating in the first speed of the D range in the automatic speed change mode. Thus, while enabling smooth shift control in the D range, in the manual mode or the first speed fixed range, the first friction engagement element is engaged,
The engine brake can be operated according to the driver's operation intention, and the drivability of the automatic transmission having the manual mode and the automatic speed change mode can be improved.

Further, a fourth aspect of the invention is that when the engine brake control valve is driven to control the solenoid valve and the shift command means selects the 1st speed fixed range, the forward line pressure circuit is applied to the first friction engagement element. Since the hydraulic pressure of 1 is supplied and the hydraulic pressure is fastened, it is possible to operate the engine brake in the first speed fixed range even if the solenoid valve fails.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the accompanying drawings.

1 to 3 show an example in which the present invention is applied when a manual mode is added to the latter conventional example.

First, FIG. 1 schematically shows an automatic transmission, in which an input shaft 2 is an output shaft 1 of an engine (not shown) via a torque converter 3 having a lockup clutch 3L.
The first planetary gear 4 and the second planetary gear 5 are mainly arranged between the input shaft 2 and the output shaft 6 of the automatic transmission, and these first and second planetary gear mechanisms 4, The low and reverse brakes L & R / B (first frictional engagement element), the overrun clutch OVR / C (second frictional engagement element), etc. are arranged as the frictional engagement elements for switching the power transmission path of No. 5 as described later. There is.

The first planetary gear 4 is composed of a sun gear 4S,
The pinion 4P meshing with the ring gear 4R is a simple planetary gear consisting of a carrier 4C rotatably and revolvably supported, and the second planetary gear 5 is also rotatable similarly to the sun gear 5S and the pinion 5P meshing with the ring gear 5R. It is configured as a simple planetary gear composed of a carrier 5C that is supported so as to be able to revolve.

First, the carrier 4C of the first planetary gear 4 is selectively engaged with the input shaft 2 via the high clutch H / C, and the sun gear 4S can be selectively fixed via the band brake B / B. With reverse clutch R / C
Is selectively fastened to the input shaft 2 via.

Further, the carrier 4C has a low-and-reverse brake L & R selectively fixed to the casing side.
/ B is provided, and while transmitting power from the input shaft 2 side to the output shaft 6 side only during acceleration, a low one-way clutch LO / C that blocks power transmission from the output shaft 6 side to the input shaft 2 side Is installed. The carrier 4C is selectively fastened to the input shaft 2 via the high clutch H / C.

The ring gear 4R is integrally connected to the carrier 5C and is also connected to the output shaft 6.

The sun gear 5S of the second planetary gear 5 is connected to the input shaft 2, and the ring gear 5R is selectively engaged with the carrier 4C side via the overrun clutch OVR / C and the forward one-way clutch FO /
C and the forward clutch F / C are arranged, and when the forward clutch F / C is engaged, the forward one-way clutch FO / C operates to transmit power from the input shaft 2 side to the output shaft 6 side only during acceleration. On the other hand, the power transmission from the output shaft 6 side to the input shaft 2 side is blocked.

Among the above-mentioned friction engagement elements, the high clutch H
/ C is engaged when in 3rd speed or higher, and band brake B /
B is engaged in the second speed or higher.

Here, in the case where the command to the automatic transmission is configured as in the shift gate 92 shown in FIG. 7, in the automatic transmission mode, the first speed in the D range (hereinafter, D1) is different from the conventional example. Similarly, in order to prevent the operation of the engine brake, power is transmitted only from the input shaft 2 to the output shaft 6 side, while in the first speed fixed range of the automatic speed change mode and the first speed of the manual mode, the engine brake is operated. Each fastening element is operated as shown in the following table so that power is transmitted from the output shaft 6 to the input shaft 2 side.

[0029]

[Table 1]

That is, in FIG. 1, in the first speed D1 in the D range, only the forward clutch F / C is engaged,
Only when in the accelerating state, the second through the low one-way clutch LO / C and the forward one-way clutch FO / C
The ring gear 5R of the planetary gear 5 is fixed, and the driving force is transmitted from the sun gear 5S coupled to the input shaft 2 to the output shaft 6 via the carrier 5C that supports the pinion 5P.

In the decelerated state, that is, when the driving force is input from the output shaft 6 side, the forward one-way clutch F
Since the O / C and the low one-way clutch LO / C idle, the ring gear 5R rotates in accordance with the carrier 5C, power is not transmitted to the input shaft 2 side, and the engine brake does not operate.

On the other hand, in the first speed fixed range (“1” in the table) and the first speed in the manual mode (M1 in the table), the low and reverse brake L & R / B, the overrun clutch OVR / C, and the low and reverse brake L & R / B
Since the ring gear 5 is fixed regardless of the acceleration / deceleration state, the driving force of the engine is transmitted from the input shaft 2 to the output shaft 6 as in the first speed of the D range in the automatic speed change mode. In the decelerating state, power can be transmitted from the output shaft 6 to the input shaft 2 via the carrier 5C and the pinion 5P to operate the engine brake.

Here, FIG. 2 shows a main part of a shift control device for performing shift control in the first speed of the automatic shift mode and the manual mode as described above, and FIG. 3 is a circuit conceptual diagram. Will be described in detail.

The control of the engaging elements in the first speed is as shown in FIG. 2 by the manual valve 17, the first and second shift valves 10 and 11 (shift valves), the overrun clutch control valve 12, the overrun clutch reducing valve 13. , Fast reducing valve 14 and shuttle shift valve 15, first and second shift solenoids 20 and 21 for supplying signal pressure to first and second shift valves 10 and 11, and signal to overrun clutch control valve 12. An overrun clutch solenoid 22 (solenoid valve) that supplies pressure is mainly configured.

First, the manual valve 17 is the same as that shown in FIG.
Shift lever 9 guided to shift gate 92 similar to
3 connected to the line pressure circuit 30 according to the shift position.
Line pressure is supplied to each circuit from the line pressure port 17L that communicates with, and the relationship between the position of the shift lever 93 and the communication state with each port 17D, 17I, 17II, 17R is set as shown in Table 2 below. It

[0036]

[Table 2]

Note that FIG. 2 shows a case where the 1st speed fixed range is selected by the shift lever 93, and in this 1st speed fixed range, the line pressure PL supplied from the line pressure port 17L.
Are supplied to the D range pressure circuit 32 through the port 17D, the two range pressure circuit 33 (P2) through the port 17II, and the one range pressure circuit 34 (P1) through the port 17I. It should be noted that the one-range pressure circuit 34 is a circuit in which the one that was conventionally connected to the port 14C of the fast reducing valve 14 is cut off.

Further, the first and second shift solenoids 20 and 21 for controlling the first and second shift valves 10 and 11 for setting the shift speed are turned on or off according to the shift speed selected by a controller (not shown). Signal pressure Psol from the first and second shift solenoids 20 and 21
The spools 10B and 11B operate according to A and PsolB.

First and second shift solenoids 20, 21
Communicates with the oil chambers 10A, 11A of the first and second shift solenoids 20, 21 via the oil passages 50, 51 to supply the signal pressures PsolA, PsolB obtained by adjusting the pilot pressure Pp from the pilot pressure circuit 31. ON and OFF of these first and second shift solenoids 20 and 21
Are driven by a controller (not shown) as shown in the following table according to the shift speed.

[0040]

[Table 3]

First and second shift solenoids 20, 21
When ON, the signal pressures PsolA and PsolB are generated, while when OFF, the signal pressure is not generated. According to the signal pressures PsolA and PsolB, the spools 10B and 11B of the first and second shift valves are set to the spring 1
Displace each against 0E and 11E.

The first shift valve 10 has a port 10C communicating with the port 11C of the second shift valve 11 and a port 10D communicating with an oil passage 60 communicating with the low and reverse brake L & R / B via the shuttle valve 16.
And the port 10D communicates with the port 10C or the drain according to the displacement of the spool 10B.

The second shift valve 11 includes the port 1
Port 11D for selective communication with 1C or drain
And a port 11F communicating with the port 12D of the overrun clutch control valve 12 via the D range pressure circuit 32, and the port 11D is connected to the port 14B of the fast reducing valve 14 via the oil passage 59.
Communicate with.

The first reducing valve 14 has a spool 14A having one end biased by a spring 14E and the other end defining an oil chamber 14D. An orifice is formed inside the spool 14A. Oil chamber 1
4D communicates with the port 14B communicating with the oil passage 59 through this orifice. Then, the port 14B selectively communicates with the port 14C or the drain according to the displacement of the spool 14A.

The port 14C communicates with the oil passage 54 via the oil passage 55. In addition, the port 14C is the same as the port 14C that has been communicated with the one-range pressure circuit 34 in the past.
5 is newly provided and connected to the oil passage 54. Therefore, the fast reducing valve 14 regulates the line pressure applied to the port 14C as a fast reducing pressure balanced with the spring 14E, and the oil passage 5
The pressure is supplied from the port 14B to the second shift valve 11 via the port 9. When the line pressure is supplied to the port 12C of the overrun clutch control valve 12, which will be described later, a fast reducing pressure is generated and a low While the reverse brake L & R / B is engaged, when the port 12C is drained, the low and reverse brake L & R / B is released.

Next, the shuttle shift valve 15 for supplying the signal pressure PsolOVR to the overrun clutch control valve 12 has a spool 15A whose one end is urged by the hydraulic pressure from the spring 15E and the port 15D and the other end of which is constantly in contact. Will be housed. Therefore, the ports 15B and 15C of the shuttle shift valve 15 are always in communication and the signal pressure Ps from the overrun clutch solenoid 22 is kept constant.
olOVR is always supplied to the port 12A.

The overrun clutch solenoid 22 for controlling the overrun clutch control valve 12 via the shuttle shift valve 15 and the oil passage 53.
Depending on the shift range selected by the shift lever 93.
N and OFF are determined as shown in the table below.

[0048]

[Table 4]

The overrun clutch solenoid 22 driven by a controller (not shown) adjusts the pilot pressure Pp from the pilot pressure circuit 31 to obtain a signal pressure Pso.
shuttle shift valve 15 through the oil passage 52
The signal pressure PsolOVR is generated when it is ON, while the signal pressure is not generated when it is OFF, and the spool 12B of the overrun clutch control valve 12 is moved to the spring 12E according to the signal pressure PsolOVR. Displace against. The oil chamber 12G that houses the spring 12E is the same as the oil chamber 12G that was conventionally connected to the oil passage 59 via the port 12F.
It is changed so as to be connected to the drain, and prevents the spool 12B from being pressed by the fast reducing pressure.

The overrun clutch control valve 12 is selectively connected to the port 12D or the drain and is also connected to the overrun clutch reducing valve 13D via the oil passage 54.
C is formed.

Therefore, when the overrun clutch solenoid 22 for generating the signal pressure PsolOVR is ON, the spool 12B is displaced upward in the figure to connect the oil passage 54 to the drain, while when it is OFF, the spool 12B is shown in FIG. As shown in FIG.
Connect to 2 to supply line pressure.

The overrun clutch OVR / C
The overrun clutch reducing valve 13 that adjusts the oil pressure to the valve has a spool 13B having one end biased by a spring 13E and the other end defining an oil chamber 13A. Is formed with an orifice, and the oil chamber 13A communicates with the port 13F communicating with the overrun clutch OVR / C through this orifice. Then, the port 13F selectively communicates with the port 13D or the drain according to the displacement of the spool 13B to regulate the hydraulic pressure to the overrun clutch OVR / C. Further, the port 13D communicates with the oil passage 57 via the oil passage 56 and the check valve 18. Therefore, port 1
The line pressure applied to 3D is adjusted so as to balance with the spring 13E that presses the spool 13B upward and the hydraulic pressure applied to the two-range pressure circuit 33, and the overrun clutch OVR / C is engaged, while the overrun clutch control is performed. When the port 12C of the valve 12 is drained, the overrun clutch OVR / C is released.

With the above construction, the operation will be described below.

A case where the automatic transmission shown in FIG. 1 is selected by the shift control device shown in FIGS. 2 and 3 for each shift mode or shift range will be described in detail.

[First Speed Fixed Range in Automatic Gear Shift Mode] As shown in FIG. 2, when the manual valve 17 is set to the first speed fixed range, the line pressure port 17L changes to the port 1
The line pressure PL is supplied from the line pressure circuit 30 to the D range pressure circuit 32, the 2 range pressure circuit 33, and the 1 range pressure circuit 34 in communication with 7D, 17I, and 17II.

Each solenoid is controlled by a controller (not shown) as follows.

First, from Table 3 above, while the first shift solenoid 20 and the second shift solenoid 21 are turned on to generate the signal pressures PsolA and PsolB, respectively,
From Table 4 above, the overrun clutch solenoid 22 is O
It becomes FF and the signal pressure PsolOVR is not generated.

Therefore, as shown in FIG. 2, the first and second
The spools 10B, 11B of the shift valves 10, 11 are displaced upward as shown by the signal pressures PsolA, PsolB of the oil chambers 10A, 11A against the springs 10E, 11E. 1
0C and 10D communicate with each other, and in the second shift valve 11, ports 11C and 11D communicate with each other so that the fast reducing pressure from the fast reducing valve 14 is transmitted from the oil passages 59, 58 and 60 and the shuttle valve 13. Road 6
Low and reverse brake L & R / B supplied to 1
Is concluded.

On the other hand, the spool 12B of the overrun clutch control valve 12 has a signal pressure PsolOVR.
Is not generated, the spring 12E urges it to displace downward as shown. Therefore, ports 12C and 12
D communicates, and the line pressure PL of the D range pressure circuit 32 is supplied to the port 13B of the overrun clutch reducing valve 13 via the oil passage 54. At the same time, since the line pressure PL is supplied to the port 13C of the overrun clutch reducing valve 13 that communicates with the two-range pressure circuit 33, the spool 13B is displaced upward in the drawing to move from the port 13D to the port 13F to the oil chamber 13A. The hydraulic pressure balanced with is guided to the oil passage 57 to engage the overrun clutch OVR / C.

Further, the forward clutch F shown in FIG.
Since / C is connected to the D range pressure circuit 32, when the line pressure PL is supplied to the port 17D, it is always in the engaged state.

Thus, in the first speed fixed range in the automatic speed change mode, as shown in "1" of Table 1, the low and reverse brake L & R / B and the overrun clutch OVR /
C and the forward clutch F / C are all engaged, power is transmitted from the input shaft 2 to the output shaft 6 in the acceleration state to drive the vehicle, while power is transmitted from the output shaft 6 to the input shaft 2 in the deceleration state. It is possible to apply the engine brake.

[First speed D1 in the D range in the automatic shift mode
In FIG. 2, when the manual valve 17 is set to the D range, the line pressure port 17L changes to the port 17D.
The line pressure PL is supplied from the line pressure circuit 30 to only the D range pressure circuit 32 in communication with the line pressure PL.

The first shift solenoid 20 and the second shift solenoid 20
The shift solenoid 21 is similar to the first speed fixed range,
When turned on, the signal pressures PsolA and PsolB are generated, and the spools 10A and 10 are operated in the same manner as above.

On the other hand, from Table 4 above, since the overrun clutch solenoid 22 is turned on and the signal pressure PsolOVR is generated, the sleeve 12B of the overrun clutch control valve 12 is displaced upward in FIG. 2 against the spring 12E. Then, the port 12C is connected to the drain, and the oil passages 54 and 55 are also connected to the drain.

Therefore, since no oil pressure is applied to the port 13C of the overrun clutch reducing valve 13 and the port 13D is also connected to the drain, the overrun clutch is provided via the check valve 18. The OVR / C hydraulic pressure is discharged and released.

Further, since the oil passage 55 is also connected to the drain through the oil passage 54, the port 14B of the fast reducing valve 14 is also connected to the drain together with the port 14C, and the fast reducing of the low and reverse brake L & R / B is performed. The ducing pressure is discharged from the overrun clutch control valve 12 through the second and first shift valves 11 and 10 and released, and as shown in Table 1 above, only the forward clutch F / C is engaged to accelerate the vehicle. Only when the power is transmitted from the input shaft 2 to the output shaft 6, the power transmission in the opposite direction is blocked as described above,
Prohibit engine braking.

[First Speed in Manual Mode] In the manual mode, the manual valve 17 is set to D in FIG.
When set to the range, the line pressure port 17L communicates with only the port 17D, and the line pressure PL is supplied from the line pressure circuit 30 to only the D range pressure circuit 32.

The operation of each solenoid is shown in Table 3 and Table 4.
Therefore, the first shift solenoid 20 and the second shift solenoid 21 are turned on in the same manner as in the first speed fixed range.
The overrun clutch solenoid 22 is turned off, and the signal pressures PsolA, PsolB and PsolOVR
While the signal pressure PsolOVR is not generated, the positions of the spools 10B, 11B and 12B are shown in FIG.
Similarly to the above, as shown in Table 1 above, the low and reverse brake L & R / B and the overrun clutch O
When the VR / C forward clutch F / C is all engaged and the vehicle is driven by transmitting power from the input shaft 2 to the output shaft 6 in the acceleration state, the power from the output shaft 6 to the input shaft 2 is transmitted in the deceleration state. Transmission is possible and engine braking can be activated.

Thus, the hydraulic pressure of the one-range pressure circuit 34 is prohibited from acting on the fast reducing valve 14, and the fast reducing pressure is prohibited from acting on the oil chamber 12G of the overrun clutch control valve 12. At the same time, the shuttle shift valve 15 is fixed, and the signal pressure PsolOVR of the constant overrun clutch solenoid 22 is always applied to the port 12A of the constant overrun clutch control valve 12. Therefore, in the first speed of the D range in the automatic speed change mode. , Prohibiting the engine braking to enable smooth shift control in the D range, while in manual mode or 1
Overspeed clutch solenoid 2 in fixed speed range
2 is turned off, the overrun clutch OVR / C and the low and reverse brake L & R / B are engaged, and the engine brake can be operated according to the driver's operation intention. The drivability of the transmission can be improved.

Further, in the manual mode, by constantly turning off the overrun clutch solenoid 22,
Since the pressure of the first reducing valve 14 has been adjusted before shifting to the first speed, the low and reverse brake L is activated according to the operation of the first shift valve 10 according to the shift command.
Since the hydraulic pressure to & R / B can be quickly raised, it is also possible to improve the shift response when performing the upshift from the first speed to the second speed in the manual mode.

Although the engine brake is not operated in the D range in the above embodiment, the overrun clutch OVR / C is engaged in accordance with the operating condition such as the throttle opening as in the conventional example. The engine brake may be activated.

FIG. 4 shows the second embodiment, in which the one-range pressure circuit 34 of the first embodiment is communicated with the port 12F of the overrun clutch control valve 12, and other configurations are the same as those described above. .

In this case, in the first speed fixed range, the first range pressure (line pressure) acts on the oil chamber 12G of the overrun clutch control valve 12 shown in FIG.
Since 2B is pushed down, the source pressure (line pressure) of the 1st speed fixed range is mechanically secured and the overrun clutch OVR
/ C and low and reverse brake L & R / B are engaged to apply the engine brake.

On the other hand, in the first speed of the manual mode, the overrun clutch solenoid 22 is turned off as in the above.
By doing so, the overrun clutch OVR / C and the low-and-reverse brake L & R / B can be quickly engaged to quickly perform the gear shift in the manual mode.

Further, since the source pressure of the 1st speed fixed range can be mechanically secured, it is possible to operate the engine brake at the 1st speed by selecting the 1st speed fixed range even when the solenoid 22 fails.

FIG. 5 shows a third embodiment. In the first embodiment, when shifting from the first speed to the second speed in the manual mode, the first and second shift solenoids 20 and 21 based on Table 3 are used. In addition to the control from ON to OFF, the overrun clutch solenoid 22 is turned ON only for a predetermined time Δt from the start of gear shift.
It is similar to the embodiment.

When shifting from the first speed to the second speed, the first shift solenoid becomes OF based on Table 3 and the signal pressure P
Since solA is not generated, in FIG. 2, the sleeve 10B of the first shift solenoid 10 is displaced downward in the drawing, the ports 10F and 10G communicate with each other, and the line pressure is supplied to the oil passage 62, so that the second speed (not shown) is obtained. The two-range pressure from the accumulator changes at time t0 according to the increase in the oil pressure in the oil passage 62.
, The band brake B / B corresponding to the second speed is engaged.

On the other hand, when the port 10D is drained in response to the downward displacement of the sleeve 10B, the low and reverse brake L & R / B communicating with the oil passage 60 reduces the hydraulic pressure (L & R / B pressure in the figure). However, when the shift command is generated at time t0 and only the first shift valve 10 (first shift solenoid 20 in the figure) is operated as shown in FIG. 6, the low-and-reverse brake L & R is released.
The pressure decrease of / B and the increase of the two-range pressure to the band brake B / B are overlapped with each other, and an interlock may occur as shown by the hatched portion in FIG.

Therefore, as shown in FIG. 5, when a shift command is issued at time t0, the overrun clutch solenoid 22 is turned on for a predetermined time Δt until time t1 in the figure,
The sleeve 12B of the overrun clutch control valve 12 is displaced upward in FIG.
Low and reverse brake L & R by connecting C to the drain and releasing the line pressure from the oil passages 54 and 55 communicating with the fast reducing valve 14 and also draining the fast reducing pressure from the port 14B at the same time. / B fastening pressure can be reduced in advance.

After that, from the time t1, the first shift solenoid 20 is switched from ON to OFF to operate the first shift valve 10, the shift control is performed in the same manner as above, and the overrun clutch solenoid 22 is turned OFF again.
Thus, the low-and-reverse brake L & R / B can be released promptly and smooth shift control can be realized without generating the interlock as described above.

Therefore, when shifting from the first speed to the second speed in the manual mode, the operation of the first shift valve 10 is delayed, and during this delay time, the fast reducing pressure is preliminarily supplied via the overrun clutch control valve 12. By reducing the amount, it becomes possible to smoothly perform an upshift from the first speed to the second speed in the manual mode.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an automatic transmission showing an embodiment of the present invention.

FIG. 2 is a circuit diagram of a main part of the shift control device.

FIG. 3 is a conceptual diagram of a shift control device.

FIG. 4 is a conceptual diagram of a shift control device according to the second embodiment.

FIG. 5 shows a third embodiment in which 1 is set in manual mode.
The first shift solenoid So when shifting from the second speed to the second speed
1A, an overrun clutch solenoid SolOVR, and an explanatory diagram showing operation timings of respective hydraulic pressures.

FIG. 6 shows a conventional example, in the manual mode, from 1st speed to 2nd speed.
Explanatory drawing which shows the operation timing of each 1st shift solenoid SolA, and each hydraulic pressure at the time of shifting to a high speed.

FIG. 7 is a schematic diagram of a shift gate of an automatic transmission having a manual mode.

[Explanation of symbols]

L & R / B Low and reverse brake OVR / C Overrun clutch F / C Forward clutch B / B Band brake LO / C Low one-way clutch FO / C Forward one-way clutch 10 2 Input shaft 4 First planetary gear 5 Second planetary gear 6 Output shaft 10 First shift valve (SFTVA) 11 Second shift valve (SFTVB) 12 Overrun clutch control valve (OV
R / C CNT. V) 13 Overrun clutch reducing valve (O
VR / C RED. V) 14 Fast reducing valve (1stRE
D. V) 14A Spool 14B, 14C, 12D Port 14D Spring 15 Shuttle shift valve 16 Shuttle valve 17 Manual valve 17L, 17D, 17I, 17II, 17R Port 20 First shift solenoid (Asol) 21 Second shift solenoid (Bsol) 22 Over Run clutch solenoid (OVR / Cs
ol) 30 line pressure circuit 31 pilot pressure circuit 32 D range pressure circuit 33 2 range pressure circuit 34 1 range pressure circuit 92 shift gate 93 shift lever 94 up switch 95 down switch

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63/48

Claims (4)

(57) [Claims] Claims: 1. A gear shift command means provided with an automatic gear shift mode and a manual mode for setting a gear according to a driving state or a driving operation and capable of switching to the manual mode in a D range of the automatic gear shift mode. , When the mode is switched to the manual mode, the first
A first frictional engagement element that is engaged when selecting a speed and that operates the engine brake, and a bar that is released during the first speed and is engaged during a shift to the second speed.
A second brake and a second frictional engagement element that operates the engine brake when engaged, and prohibits the operation of the engine brake when released at each of the second or higher speeds, and each speed according to the set speed. In a shift control device for an automatic transmission, which is provided with shift control means for engaging and disengaging a friction engagement element set in advance for each, the first friction engagement element and the second friction engagement element are engaged.
The control valve that generates the source pressure for this purpose and the source pressure that is generated by this control valve are
The oil passage that supplies the friction element and the oil generated by the control valve that is connected to this oil passage.
An oil passage for supplying the source pressure to the first frictional engagement element and an oil passage for supplying the source pressure to the first frictional engagement element
To switch between fastening and releasing the first friction fastening element.
Supply the source pressure supplied from the control valve
Or the shift valve is provided for interrupting said shift control means is in the first speed when the shift command unit has selected the manual mode, the control valve so as to fasten together said first and second friction engagement element and shift valve
When the automatic transmission mode D range is selected, the second friction engagement element is engaged according to the operating state .
The above manual while controlling the control valve
When shifting from 1st mode to 2nd mode,
After reducing the original pressure supplied from the valve,
A shift control device for an automatic transmission, comprising a delay drive means for permitting a brake engaging operation . 2. The shift command means includes a first speed fixed range in the automatic shift mode, and when the first speed fixed range is selected, the shift control means engages the first and second engagement elements together. The shift control device for an automatic transmission according to claim 1, wherein: 3. The shift control means is the shift command means.
Selects the automatic transmission mode D range or 1st speed fixed range
Forward range pressure circuit that supplies line pressure when selected
And the hydraulic pressure of this forward range pressure circuit is applied to the first or second friction
When the engine brake control valve that supplies or shuts off the element, the solenoid valve that drives the engine brake control valve, and the speed change valve are in the first speed position, the solenoid valve is
Drive the engine brake control valve to require the first friction engagement.
Characterized by supplying the hydraulic pressure of the forward line pressure circuit to the element
The shift control device for an automatic transmission according to claim 1. 4. The engine brake control valve is a Soleno
In addition to the control of the id valve, the speed change command means provides a fixed first speed range.
It is controlled by the hydraulic pressure supplied when selected,
Supplying the hydraulic pressure of the forward line pressure circuit to the friction engagement element
5. A shift control device for an automatic transmission according to claim 3, wherein
Place