JPH06221417A - Speed change control device for automatic transmission for vehicle - Google Patents

Abstract

PURPOSE:To improve operability by performing necessary down-shift operation speedily at the time of changing into a manual speed change mode. CONSTITUTION:When selection of a second range position D2 in which a speed change stage in which engine brake is in an effective condition can only be set by a shift device 40 is detected by a shift detection means 41, a speed change instruction means 43 instructs change into a speed change stage in which the engine brake is effective to the low speed side by a specified stage number from a speed change stage detected by a transmission stage detection means 42 immediately before that. When a mode is changed into one in which the speed change stage can be set by manual operation, down-shift occurs in accordance with the operation. Engine brake force can thus be increased, or acceleration ability can be increased, with operability for the purpose improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for operating a shift of an automatic transmission of a vehicle, for example, an automatic transmission in which an automatic transmission mode and a manual transmission mode can be selected. The present invention relates to a shift control device that shifts gears.

[0002]

2. Description of the Related Art As is well known, an automatic transmission is configured to set a shift speed according to a running state of a vehicle such as a vehicle speed and a throttle opening. Then, the speed change is executed by appropriately engaging or disengaging a clutch or a brake in a gear train mainly including the planetary gear mechanism.
For these clutches and brakes, those with a wet multi-plate structure in which friction plates are brought into contact with each other by hydraulic pressure are generally used, but it is not always easy to engage or disengage them in a timely manner, especially in a power-on state. A shift shock is likely to occur at the time of shifting. Therefore, a general automatic transmission is configured to smoothly shift gears by using a one-way clutch. However, since the one-way clutch is a directional engaging means, when torque is input from the output shaft side, the torque is input into the disengaged state and the torque is transmitted. Can not do it. Therefore, generally, a multi-disc clutch, a multi-disc brake, or a band brake is provided in parallel with the one-way clutch, and the shift lever is operated to switch the manual valve, so that selection can be made even in a low speed stage such as the first speed or the second speed. I try to make the engine brake effective.

The so-called engine brake range in which the engine brake is applied in the low speed stage is selected by operating the shift lever. Even in the engine brake range, the shift stage is basically the running state such as vehicle speed and throttle opening. It is set according to. Therefore, even if shifting to the engine brake range, the downshift does not occur, so that the engine braking may not be effective or may not be effective. On the contrary, there may be a case where two or more downshifts occur and the engine braking is excessively activated.

By the way, heretofore, an apparatus capable of switching between an automatic shift mode in which a shift speed is set based on a running state and a manual shift mode in which a shift is performed based on a manual operation is disclosed in Japanese Patent Laid-Open No. 2-8545. Has been done. In the shift device described in this publication, the shift path that defines the range of movement of the shift lever is formed in a substantially "H" shape, and shifts from the D range position in the automatic shift mode to the second shift path for the manual shift mode. By moving the lever, one of the sensors arranged at both ends of the second shift path is operated by the shift lever to move up one step, and the other sensor is operated to It is configured to shift down. The gear set in this way is set by a manual gear shift operation, and therefore is set in a state in which the engine brake can be applied. Therefore, according to the device described in the above publication, the conventional automatic transmission is used. Unlike the transmission, the engine brake can be applied just enough by man-made operation.

[0005]

In a vehicle equipped with the shift device described in the above publication, the shift lever is automatically shifted when an engine brake state accompanied by a downshift is obtained while traveling in the automatic shift mode. From the D range position for the vehicle to the second shift path, and further in the second shift path, the sensor for downshift is moved in the direction to operate. Therefore, there is a problem that at least two operations are required in order to reliably obtain the engine braking state accompanied by one downshift, and therefore the operability and responsiveness are not always sufficient. Also, in order to obtain high acceleration, switch to the manual shift mode and
Even when selecting the shift speed on the lower speed side, as in the case described above, two operations, that is, switching to the second shift path and ON operation of the downshift switch, are required, and there is a disadvantage that operability is poor.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a shift control device capable of reliably obtaining an engine braking state and high power performance with good operability.

[0007]

In order to achieve the above object, the present invention is characterized by having the structure shown in the drawing. That is, the invention described in claim 1 is as shown in FIG.
As shown in, in a shift control device for an automatic transmission for a vehicle in which a plurality of shift speeds can be set, including a selectable speed state in which the engine brake is applied and a state in which the engine brake is not applied, the engine brake is not applied. A plurality of shift speeds including the current shift speed are set based on the traveling state;
The shift device 40, which is selectable by manual operation, between the range position D1 and the second range position D2 which is provided adjacent to the first range position D1 and which sets only the gear position in the state where the engine braking is effective, and the second range The shift detecting means 41 for detecting the selection of the position D2 and the shift device 40 are arranged in the first range position D1 to the second range position D.
When the shift detecting means 41 detects that the second range position D2 has been selected as a result of switching to 2, shift speed detecting means 42 for detecting the shift speed immediately before the second range position D2 is selected. When the shift detecting means 41 detects that the second range position D2 has been selected, the shift speed detected by the shift speed detecting means 42 is shifted to a shift speed in a state in which engine braking is in effect at a speed lower than the shift speed detected by a predetermined number. And a shift instruction means 43 for instructing the shift.

Further, the invention according to claim 2 is a shift control of an automatic transmission for a vehicle capable of being set to a plurality of shift stages including a shift stage in which an engine brake effective state and an engine brake ineffective state can be selected. In the device, a first range position D1 for setting a plurality of gear stages including a gear stage in which the engine brake is not effective based on the running state, and a state in which the engine brake is effective and is provided adjacent to the first range position D1. The shift device 40 that can manually select the second range position D2 that sets only the gear position, the shift detection unit 41 that detects that the second range position D2 is selected, and the shift device 40 As the range position D1 is switched to the second range position D2, the shift detecting means 41 detects that the second range position D2 is selected. A gear position detecting means 42 for detecting the gear position immediately before the second range position D2 is selected in case,
Downshift intention determining means 44 for determining that the selection of the second range position D2 is intended for downshift, and it is determined that the selection of the second range position D2 is intended for downshift. In addition, when the downshift detection means 41 detects that the second range position D2 is selected, the shift speed detected by the shift speed detection means 42 is lower than the shift speed detected by a predetermined number of speeds and the engine brake is in a state in which the engine brake is effective. And a shift instruction means 43 for instructing a shift to.

[0009]

According to the invention described in claim 1, when the first range position D1 is selected by the shift device 40, the automatic transmission is set to any one of a plurality of shift stages including a shift stage in which engine braking is not effective. It is set according to the running condition. When the shift device 40 is switched from the first range position D1 to the second range position D2, the shift detection means 41 detects that the second range position D2 is selected, and
The gear position detecting means 42 detects the gear position immediately before the second range position D2 is selected. Then, the shift instruction means 43
A shift instruction is issued to set a shift speed lower than the shift speed detected by the shift speed detecting means 42 by a predetermined number of shift speeds and in a state where engine braking is effective. Therefore, the downshift can be executed by only one operation, which is the switching from the first range position D1 to the adjacent second range position D2.

According to the second aspect of the present invention, when the first range position D1 is switched to the second range position D2, the selection of the second range position D2 and the detection of the gear position immediately before that are detected. In addition, if the downshift intention detecting means 44 detects whether or not the selection of the second range position D2 is intended for downshift, and it is detected that it is intended for downshift. ,
A shift instruction is issued to set a shift speed lower than the shift speed detected by the shift speed detecting means 42 by a predetermined number of shift speeds and in a state where engine braking is effective. Therefore, also in this case, the downshift can be executed by only one operation, which is the switching from the first range position D1 to the adjacent second range position D2.

[0011]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 3 is a schematic block diagram showing an embodiment of the present invention, in which an automatic transmission A has a torque converter 2 having a lockup clutch 1 and a set of planetary gear mechanisms as a speed change mechanism. A second speed change unit 3 and a first speed change unit 4 that sets a plurality of forward speeds and reverse speeds by two sets of planetary gear mechanisms are provided.

The second transmission section 3 is for switching between high and low stages and has a carrier 5 of the planetary gear mechanism.
Is connected to the turbine runner 6 of the torque converter 2, and a clutch C0 and a one-way clutch Fo are provided between the carrier 5 and the sun gear 7 so as to be in parallel relationship with each other. H
A brake B0 is provided between u and U.

The sun gears 8 and 9 in each planetary gear mechanism of the first transmission section 4 are provided on a common sun gear shaft 10, and the left side (front side) of the first transmission section 4 in the drawing.
Of the planetary gear mechanism and the second speed change portion 3
A first clutch C1 is provided between the sun gear shaft 10 and the ring gear 12 of the second speed change portion 3, and a second clutch C2 is provided between the sun gear shaft 10 and the ring gear 12 of the second transmission portion 3. The carrier 13 of the planetary gear mechanism on the left side of the drawing and the ring gear 14 of the planetary gear mechanism on the right side (rear side) in the first transmission section 4 are integrally connected, and the carrier 13 and the ring gear 14 have an output shaft. 15 are connected.

A first brake B1 which is a band brake is provided to stop the rotation of the sun gear shaft 10,
More specifically, it is provided on the outer peripheral side of the clutch drum of the second clutch C2, and the first one-way clutch F1 and the second brake B2 are arranged in series between the sun gear shaft 10 and the housing Hu. Further, the second one-way clutch F2 and the third brake B3 are arranged in parallel between the carrier 16 and the housing Hu in the planetary gear mechanism on the rear side.

The hydraulic control device 17, which supplies and discharges hydraulic pressure to and from the clutches C0, C1 and C2 and the brakes B0, B1, B2 and B3, mainly performs the first to fourth speed shifts. First and second solenoid valves S of
1, S2, a linear solenoid valve SLU for mainly controlling the lockup clutch 1, and a motor 18 for driving a manual valve (not shown) for switching the traveling range. That is, the automatic transmission A is configured as a so-called shift-by-wire automatic transmission that switches the range by an electric signal.

The first and second solenoid valves S
1, S2 and electronic control unit for controlling the linear solenoid valve SLU (hereinafter referred to as T-ECU) 19
And an electronic control device for switching the driving range (hereinafter,
SBW-ECU) 20 is provided.
Each of these EUCs 19 and 20 is a central processing unit (CP
U) and storage elements (ROM, RAM) and input / output interface as main components,
U19 has the same throttle opening signal,
Vehicle speed signal, pattern select signal, engine water temperature signal,
Signals such as brake signals are input, and this T-EC
U19 calculates and obtains a shift stage to be set based on these input signals and a shift map stored in advance, and the first and second solenoid valves S1 and S2 are set to set the shift stage. To the linear solenoid valve SLU.

On the other hand, the SBW-ECU 20 selects a parking (P) range, a reverse (R) range, a neutral (N) range, a drive (D) range, an engine brake (B) range, and an upshift operation. Also, a shift device 21 for downshift operation is connected. Each of these range positions is, as shown in the figure, P-
The switches are arranged in the order of R-N-D-B, and a range switch (not shown) that is turned on by the shift lever 22 is provided at each of these range positions. When the switch in any of the P range, R range, N range, and D range of these range switches is turned on, the SBW-ECU 20 causes the motor 1 to operate.
8 is operated to switch the manual valve so that the traveling range corresponds to the range switch that is on. When the B range switch is turned on, the SBW-ECU 20 drives the motor 18 and the range where engine braking is effective (S range or L described later).
A range) is selected, and a gear stage instruction signal is output to the T-ECU 19 to downshift the current gear stage by one stage.

Further, the shift device 21 is provided with an upshift position and a downshift position at left and right positions sandwiching the B range position, and an upshift position which is turned on by a shift lever 22 is provided at the upshift position. A switch Swu is provided, and a downshift switch Swd that is turned on by the shift lever 22 is provided at the downshift position. When these shift switches Swu and Swd are turned on, the SBW-E
The CU 20 outputs a signal to the motor 18 when necessary,
A shift signal is output so that the gear is shifted to a gear position where the engine brake is in effect. Specifically, the up-shift signal is sent when the up-shift switch Swu is turned on, and the down-shift signal is sent when the down-shift switch Swd is turned on.
Output to.

The on / off states of the solenoid valves S1 and S2 and the engagement / disengagement states of the friction engagement devices in each range in the automatic transmission A are as shown in FIG. In FIG. 4, ◯ indicates ON for the solenoid valves S1 and S2, engagement for the friction engagement device, and X indicates OFF for the solenoid valves S1 and S2, and release for the friction engagement device. .

When the P range, the R range, the N range, or the D range is selected by the shift device 21, the shift solenoid valves S1 and S2 are turned on as shown in FIG. 4, and the selected range is selected. The motor 18 is driven so that the hydraulic pressure is sent from the manual valve to a predetermined friction engagement device. The shift control in these ranges is similar to that of a conventional general automatic transmission. On the other hand, when the B range is selected by the shift device 21, the following control is performed.

FIG. 5 is a flow chart showing the control routine when the switch in the B range position is turned on. In step 1, it is judged whether or not the switch in the B range position is turned on, and the result of the judgment is shown. If is “No”, the control is terminated, and if “Yes”, Step 2
At, it is determined whether the range before the shift was the D range. When the D range is switched to the B range, the result of the determination in step 2 is "Yes". In that case, it is determined in step 3 whether or not the immediately preceding gear stage was the 4th speed, and it is the 4th speed. If so, the routine proceeds to step 4, and a shift instruction signal for setting the shift stage to the third speed is output. The third speed is a gear speed set by connecting the gear train shown in FIG. 3 so that the entire gear train rotates integrally, and is therefore a gear speed at which engine braking is effective. As can be seen from the operation table shown in FIG. 4, the third speed can be set even when the S range is selected. Therefore, in step 4, the travel range may be switched to the S range.

If the result of the determination in step 4 is "no", the process proceeds to step 5 to determine whether or not the immediately preceding gear is the third speed, and if it is the third speed, the process proceeds to step 6. , And outputs a shift instruction signal for downshifting the shift stage to the second speed while setting the traveling range to the S range. In the second speed in the S range, as shown in the operation table of FIG. 4, the first brake B1 which is a band brake is engaged, so that the engine brake can be activated. If the result of the determination in step 5 is "no", step 7
4, the gear shift instruction signal for downshifting the gear position to the first speed is output when switching to the L range shown in the operation table in FIG. At the first speed in the L range, the third brake B3 is engaged, so that the engine braking can be activated.

On the other hand, if the result of the determination in step 2 is "no", the process proceeds to step 8 to determine whether or not the previous range was the S range, and if it is the S range, the process proceeds to step 9. It is determined whether the third speed has been set. If it is the third speed, a shift instruction signal for downshifting to the second speed is output (step 10), and if it is not the third speed, it is switched to the L range and the first speed is set.
An instruction signal for downshifting to high speed is output (step 7). Further, this downshift instruction to the first speed in the L range is similarly executed even when the result of the determination in step 8 is "no".

The above range switching is performed by SBW-EC.
The U20 outputs a drive signal to the motor 18, and the downshift is performed by the SBW-ECU 20.
A gear stage instruction signal is output to the -ECU 19, and the T-ECU 20 is executed by turning on and off the solenoid valves S1 and S2 accordingly. Therefore, if the B range is selected, one downshift is performed, and the gear set by the downshift is a gear in which engine braking is effective. Therefore, according to the above device, the shift lever 22 is set to D The engine braking state can be reliably obtained by only one operation of moving from the range position to the B range position adjacent thereto.

The downshift accompanied by the above range switching can be performed by rereading the shift map, an example of which is shown in FIG. That is, when the vehicle travels in the D range, the traveling state changes to the state indicated by point X in the D range shift map due to the decrease in vehicle speed. If the range is switched to the B range here, at the point X in the D range shift map. , 3rd speed is maintained because it has not crossed the downshift line to 2nd speed, but with the change to B range S
If it is read as a shift map for range, the running state of point X in the shift map for S range is in the range of the second speed, and accordingly, the shift state for the B range is changed to the third range.
A downshift occurs from the second speed to the second speed where the engine brake is applied.

By the way, in the apparatus shown in FIG. 3, when the shift lever 22 is moved from the B range position to the right or left in FIG. 3, the upshift switch Swu or the downshift switch Swd is turned on, and SB is accordingly accompanied.
The W-ECU 20 outputs to the T-ECU 19 a gear stage instruction signal for the first-speed high-speed side gear stage or the first-stage low-speed side gear stage in which engine braking is effective. That is, by shifting the shift lever 22 to the right or left in FIG. 3 from the B range position, gear shifting can be performed by manual operation.

The above-mentioned embodiment is an example in which the present invention is applied to a shift-by-wire automatic transmission.
The invention can also be applied to a shift control device for another automatic transmission, for example, an automatic transmission capable of selecting an automatic transmission mode and a manual transmission mode, and an example thereof will be described below.

In FIG. 7, an automatic transmission A includes a solenoid valve S1 and S2 for shifting in the hydraulic control device 30.
, S3, the line pressure solenoid valve SLT, the lockup clutch solenoid valve SLU, and the accumulator back pressure solenoid valve SLN are controlled by the electronic control unit (ECU) 31 for the automatic transmission and are operated by the shift lever 32.
3, a manual valve (not shown) is operated to set a predetermined gear.

The shift device 33 includes a range lever of parking (P), reverse (R), neutral (N), drive (D), manual (M) and low (L), and a shift lever from the manual range position. The shift lever 32 selects an upshift position where the 32 is moved to output the upshift signal and a downshift position where the downshift signal is output. At the upshift position and the downshift position, a shift switch (not shown) that outputs a shift signal when turned on by the shift lever 32 is provided, and these switches are connected to the electronic control unit 31. ing.

The electronic control unit 31 mainly includes a central processing unit (CPU), storage elements (ROM, RAM) and an input / output interface, and has a vehicle speed V, a throttle opening θ, a brake signal, Various signals such as a pattern select signal are input to control the shift solenoid valves S1 and S2 so as to set the shift stage according to the running state in the automatic shift mode. In the manual shift mode, the upshift switch is set to 1 The hydraulic control device 30 is configured to upshift one step each time it is operated.
The shift solenoid valves S1 and S2 are operated, and the shift solenoid valves S1 and S2 of the hydraulic control device 30 are operated so as to downshift by one step each time the downshift switch is operated. . The shift positions of each range in the shift device 33 are arranged as shown in FIG.

The gear train in the automatic transmission A is constructed as shown in FIG. Further, FIG. 9 is a diagram showing an example of the hydraulic control device 30 that executes the gear shift for the gear train in the automatic gear shift mode and the manual gear shift mode.

That is, the automatic transmission A provided with the above-mentioned gear train can set the first speed to the fourth speed in the forward speed, and among these, the first speed and the second speed are in the automatic speed change mode in the engine. Since the brake does not work and it is necessary to apply the engine brake in the manual shift mode, the hydraulic circuit shown in FIG. 9 is incorporated in the hydraulic control device 30.

The manual valve 100 switches the supply / discharge state of hydraulic pressure by moving the spool 101 by the shift device 33, and the line pressure P regulated by a primary regulator valve (not shown).
A line pressure oil passage 60 for supplying L is connected to the input port 102, and in the D range, the spool 101 is at the position shown in the figure so that the input port 102 communicates with the D port 103. In the M range, spool 10
1 moves to the lower side of the figure and the input port 102 is the D port 1
03 and M port 104, in the L range, the spool 101 moves further downward so that the input port 102 communicates with the D port 103, the M port 104 and the L port 105, and vice versa. In the spool 101, the input port 102 is closed, and in the R range, the input port 10
2 communicates with the R port 106, closes the input port 102 in the P range, and communicates other ports with the drain port. And that D port 103
The first clutch C1 and the first solenoid valve S1 are connected to each other.

The 1-2 shift valve 200 for shifting between the first speed and the second speed is a spool 2 having four lands.
01 and a spring 202 arranged at one end thereof, the control port 203 formed at the end opposite to the spring 202 is connected to the second solenoid valve S2, and when the second solenoid valve S2 is OFF. From the line pressure oil passage 61 to the strainer 62 and the orifice 63.
A line pressure PL supplied through the control port 203 is generated at the control port 203.

Below the control port 203 in the figure, the second coast port 204 which is opened and closed by the uppermost land.
And the first brake port 20 that selectively communicates with the second coast port 204 and the drain port 205.
6 are formed in order, and the first brake port 206 is connected to the first brake port 206 via the second coast modulator valve 64.
Brake B1 is connected. Also drain port 20
5, a D port 207 connected to the D port 103 of the manual valve 100 is formed on the lower side in the figure,
A second brake B2 is connected to a second brake port 209 that selectively communicates with the D port 207 and another drain port 208. The other drain port 208
Further, another drain port 210 is formed on the lower side in the figure, and the third brake port 2 selectively communicated with the drain port 210 and the low coast port 211.
The third brake B3 is connected to 12. A hold port 213 is formed at the lowermost end where the spring 202 is arranged.

A 2-3 shift valve 300 for shifting between the second speed and the third speed has a spool 301 having seven lands and a spring 302 arranged at one end (lower end in the figure) of the spool 301. And a control port 303 formed at the end opposite to the spring 302 is connected to the first solenoid valve S1.
At the time of FF, the line pressure PL supplied from the D port 103 of the manual valve 100 through the strainer 65 and the orifice 66 is generated at the control port 303.

The 2-3 shift valve 300 includes a first drain port 304 and a brake port 3 in order from the top of the drawing.
05, the first M port 306 is formed, the brake port 305 is connected to the second coast port 204 of the 1-2 shift valve 200, and the brake port 305 is connected to the first drain port 304 and the first drain port 304.
It is adapted to selectively communicate with the M port 306. Continuing with the above port, the second drain port 307,
A hold output port 308, an input port 309, a clutch port 310, and a third drain port 311 are formed in order, and the first drain port 304 and the brake port 3 are formed.
05, the first M port 306 is shut off, the hold output port 308 communicates with the second drain port 307, and the input port 309 and the clutch port 3
It communicates with 10. Further, when the brake port 305 communicates with the first M port 306, the hold output port 308 and the input port 309, and the clutch port 310 and the third drain port 311 communicate with each other.

Further, a brake port 312 and a second M port 313 are sequentially formed following the third drain port 311, and when the clutch port 310 is in communication with the input port 309, the third drain port 311 is connected to the brake port 312. To the clutch port 31
When 0 communicates with the third drain port 311, the brake port 312 communicates with the second M port 313. Furthermore, a hold port 314 is formed at the lowermost end where the spring 302 is arranged.

The second clutch C2 is connected to the clutch port 310, while the 1-2 shift valve 2 is connected.
00 hold port 213 and this clutch port 31
0 and 0 are connected. Also, the first M port 306 and the second
The M port 313 is connected to the M port 104 of the manual valve 100. Further brake port 312
Is connected to the low coast port 211 of the 1-2 shift valve 200 via the low coast modulator valve 67, and the hold port 314 is connected to the manual valve 10.
No. 0 is connected to the L port 105, and in the L range, the spool 301 is held at the pushed up position as shown in the right half of the figure.

The 3-4 shift valve 400 is controlled by the hydraulic pressure sent from the second solenoid valve S2 and the hold output port 308 of the 2-3 shift valve 300,
The second gear shifting unit 30 is configured to perform gear shifting, and includes a spool 401 having four lands and a spring 402 arranged at one end thereof, and an end opposite to the spring 402. Control port 4 formed on
03 is connected to the second solenoid valve S2 similarly to the control port 203 of the 1-2 shift valve 200 described above, and the hold port 404 formed at the end where the spring 402 is arranged has a 2-3 shift. It is connected to the hold output port 308 in the valve 300.

In this 3-4 shift valve 400, the second solenoid valve S2 is turned off and the control port 4
When the line pressure PL acts on 03, the input port 405 connected to the line pressure oil passage 61 is connected to the brake B.
0 is connected to the connected brake port 406, and conversely, when pressure is exhausted from the control port 403 or when hydraulic pressure is acting on the hold port 404, the input port 405 connects the clutch C0. It is adapted to communicate with a certain clutch port 407.

Since the solenoid valves S1 and S2 are turned on or off as shown in FIG.
In the -2 shift valve 200, the spool 201 is pushed down as shown in the right half at the first speed, and at other forward stages the spool 201 is pushed up as shown in the left half of the figure. In the first and second speeds, the spool 301 is pushed up as shown in the right half of the figure, and in the third and fourth speeds, the spool 301 is pushed down as shown in the left half of the figure. In the shift valve 400, the spool 401 is used in the first speed to the third speed.
Is pushed up as shown in the right half of the figure, and is pushed down in the fourth gear as shown in the left half of the figure. As a result, each friction engagement device is engaged or disengaged as shown in FIG. 10, and each shift speed is set.

FIG. 10 is an operation table. The circles indicate ON for solenoid valves, the frictional engagement devices indicate engagement, and the crosses indicate OF for solenoid valves.
F, the friction engagement device indicates release.

The first speed and the second speed in the manual shift mode will be particularly described. In the manual shift mode, the shift lever 12 is set to the M range position and the M port 104 communicates with the input port 102. Therefore, the line pressure PL is supplied to the first M port 306 and the second M port 313 of the 2-3 shift valve 300. Therefore, when the first speed is set, the hydraulic pressure is supplied to the first brake B1 via the brake port 305 and the 1-2 shift valve 200, and the engine braking is activated. When the second speed is set, the hydraulic pressure is supplied to the third brake B3 via the brake port 312 and the 1-2 shift valve 200, so that the engine braking is activated.

The automatic transmission A equipped with the gear train shown in FIG. 3 and the hydraulic circuit shown in FIG. 9 can perform the gear shift in the automatic gear shift mode and the gear shift in the manual gear shift mode as described above. Selection of each shift speed in the switching and manual shift modes is performed by the shift device 33 described above. That is, if the D range is selected by the shift lever 32, each gear is automatically set based on the traveling state such as the vehicle speed and the throttle opening.
2 is set to the M range position, and if the upshift switch or the downshift switch is operated to be turned ON from here, the electronic control unit 31 causes the hydraulic control unit 30 to upshift or downshift one step each time. Of the solenoid valves S1 and S2 to output a shift command signal to the shift stage one speed higher or lower than the current shift stage.

Also in the automatic transmission A shown in FIG. 7, the downshift in the manual shift mode is performed by moving the shift lever 32 from the M range position to the right in FIG. 8 and then to the downshift position (lower side in FIG. 8). However, in many cases, the reason for moving to the M range position is to increase the engine braking force by downshifting or to increase the gear ratio to increase the driving force. Therefore, in the automatic transmission A shown in FIG. 7, when the D range position is switched to the M range position, the downshift is performed as described below.

In FIG. 11, after processing the input signal (step 20), it is judged whether or not the manual shift mode (M mode) is selected (step 21). When the M mode is not selected, the process returns without performing any control, and when the M mode is selected, a shift signal is output so as to set the shift stage one speed lower than the shift stage immediately before it. (Step 22).

By performing an upshift operation following such a shift operation, it is determined whether or not an upshift signal has been input (step 23). If an upshift signal has been input, an upshift signal is input. A determination is made and a shift signal is output (step 24). On the other hand, when the upshift signal is not input, it is determined whether or not the downshift signal associated with the downshift operation is input (step 25). When the downshift signal is not input, the process returns. When the downshift signal is input, the downshift determination is performed and the shift signal is output (step 26).

Therefore, by performing the control shown in FIG. 11, it is possible to move the shift lever 32 to the M range position without intentionally performing the downshift operation, that is, only by switching to the manual shift mode, and in the D range immediately before that. It is possible to set a shift speed one speed lower than the shift speed of, and as a result, it is possible to obtain a high acceleration by increasing the engine braking force or the gear ratio.

Note that the downshift accompanying switching from the automatic shift mode to the manual shift mode may be controlled so as to more positively reflect the driver's intention, and an example thereof is shown in FIGS. 12 and 13. It is shown.

The example shown in FIG. 12 is an example in which it is determined that acceleration is required and a downshift is executed. If the determination result in step 21 is "yes", the process proceeds to step 21-1. Determines whether or not the third speed or the fourth speed is set in the automatic shift mode. When switching to the M mode while the vehicle is traveling at the third speed or the fourth speed in the automatic speed change mode, it is considered that the intention is to correct the lack of acceleration due to the small gear ratio. Therefore, if the determination result in step 21-1 is "yes", the process proceeds to step 22 described above to downshift by one step.

If the result of the determination in step 21-1 is "no", that is, if the first speed or the second speed has been set in the immediately preceding automatic speed change mode, the speed or engine brake with good acceleration performance is obtained. In this case, the downshift is not executed only by switching to the manual shift mode because it is already set to the shift stage having a large force. That is, the process proceeds to step 23 without passing through step 22. The other control processes are the same as the control shown in FIG. 11.

Further, the example shown in FIG. 13 is an example in which it is determined whether or not the engine brake is required and the downshift is controlled. That is, when it is detected in step 21 that the mode is switched to the M mode, the process proceeds to step 21-2, and it is determined whether the engine braking condition (E / B condition) is satisfied. This engine braking condition is determined by, for example, that the coast down control was being performed in the immediately preceding automatic shift mode, and the throttle opening θ is a predetermined reference opening θ1.
This can be performed by determining that any of the following conditions is satisfied, that deceleration (negative acceleration) has occurred, that the brake switch is ON, and the like. If this engine braking condition is satisfied, that is, if the result of the determination in step 21-2 is “yes”, the process proceeds to step 22 to execute the downshift, and conversely, if the engine braking condition is not satisfied, That is, when the result of the determination in step 21-2 is "NO", the process proceeds to step 23 without passing through step 22. Therefore, by performing the control shown in FIG. 13, a downshift occurs as needed only by switching to the M mode, the engine braking force can be increased, and the operability for applying the engine braking becomes good. . The other control processes are the same as the control shown in FIG. 11.

The present invention is not limited to the above embodiment, and an automatic transmission provided with a gear train other than the gear train shown in FIG. 3 or a hydraulic circuit other than the hydraulic circuit shown in FIG. The present invention can be applied to the shift control device.
Further, in each of the above-described embodiments, one downshift is performed, but the present invention may be configured to perform two or more downshifts as needed.

[0055]

As described above, according to the gear shift control device of the present invention, when the gear position is switched to the state in which the gear can be set by manual operation, the gear shift set in the automatic transmission mode immediately before that is performed. To the gear that is lower than the gear,
Since gear shifting can be performed without downshift operation, operability for applying the engine brake or operability for obtaining high acceleration is improved, and even when the engine brake is applied, the number of downshift steps By setting in advance, it is possible to avoid an excessive braking force.

[Brief description of drawings]

FIG. 1 is a block diagram showing the basic configuration of the invention described in claim 1 by functional means.

FIG. 2 is a block diagram showing the basic configuration of the invention described in claim 2 by functional means.

FIG. 3 is a block diagram schematically showing an embodiment of the present invention.

FIG. 4 is a diagram showing an engagement operation table of a friction engagement device for setting each shift speed.

FIG. 5 is a flowchart showing a control routine when the B range is selected.

FIG. 6 is an explanatory diagram of a shift map when downshifting accompanying shifting to the B range is executed by replacing the shift map.

FIG. 7 is a block diagram conceptually showing another embodiment of the present invention.

FIG. 8 is a diagram showing an arrangement of each range position in a shift device of an automatic transmission capable of selecting a manual shift mode.

FIG. 9 is a diagram showing a hydraulic circuit for performing a shift in an automatic transmission having an M range position.

10 is a diagram showing an engagement operation table of a friction engagement device for setting a forward gear in an automatic transmission mode and a manual transmission mode of the automatic transmission shown in FIG.

FIG. 11 is a flowchart showing an example of a control routine for executing a downshift when switching to the M mode.

FIG. 12 is a flowchart showing an example of a control routine for executing a downshift that reflects the driver's intention.

FIG. 13 is a flowchart showing another example of a control routine for executing a downshift that reflects the driver's intention.

[Explanation of symbols]

 40 shift device 41 shift detecting means 42 shift speed detecting means 43 shift instruction means 44 downshift intention determining means D1 first range position D2 second range position

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinji Kasuga, Toyota city, Toyota city, Aichi prefecture, Toyota Motor Corporation (72) Inventor, Yasuo Hojo, Toyota city, Aichi prefecture, Toyota city company ( 72) Inventor Hideki Miyata 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Co., Ltd.

Claims (2)

[Claims] 1. A shift control device for an automatic transmission for a vehicle in which a plurality of shift speeds can be set including a shift speed in which an engine brake effective state and an engine brake ineffective state can be selected. First range position for setting a plurality of shift speeds including the current shift speed based on the traveling state, and a second range provided adjacent to the first range position and for setting only a shift speed in a state in which engine braking is in effect A shift device capable of manually selecting a position, a shift detecting means for detecting that the second range position is selected, and the shift accompanied by switching the shift device from the first range position to the second range position. When the detection means detects that the second range position has been selected, the shift speed detection means that detects the shift speed immediately before the second range position is selected When the shift detecting means detects that the second range position has been selected, the gear shift to a gear position in which engine braking on the low speed side is effective by a predetermined number of gears from the gear position detected by the gear position detecting means. A shift control device for an automatic transmission for a vehicle, comprising: a shift instruction means for instructing. 2. A shift control device for an automatic transmission for a vehicle, wherein a plurality of shift speeds can be set including a shift speed in which an engine brake effective state and an engine brake ineffective state can be selected. First range position for setting a plurality of shift speeds including the current shift speed based on the traveling state, and a second range provided adjacent to the first range position and for setting only a shift speed in a state in which engine braking is in effect A shift device capable of manually selecting a position, a shift detecting means for detecting that the second range position is selected, and the shift accompanied by switching the shift device from the first range position to the second range position. When the detection means detects that the second range position has been selected, the shift speed detection means that detects the shift speed immediately before the second range position is selected Downshift intention determining means for determining that the selection of the second range position is intended for a downshift, and shifting when it is determined that the selection of the second range position is intended for a downshift When the detecting means detects that the second range position is selected,
An automatic shift for a vehicle, comprising: a shift instruction means for instructing a shift to a shift step in which engine braking on a low speed side is in effect for a predetermined number of shift steps detected by the shift step detection means. Gear shift control device.