JPH10169768A - Controller for vehicle with automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a controller capable of preventing a decelerating ill feeling following fail in an automatic transmission. SOLUTION: This controller for a vehicle with an automatic transmission, in which the automatic transmission to be able to set a variable speed ratio on the low speed side, where engine brake works, with electric control is connected to a running driving power source, has a fail-down shift detecting means to detect a variable speed to be generated from a variable speed ratio on the high speed side to a variable speed ratio on the low speed side, where engine brake works with fail (step 5), and a braking force reducing means to reduce braking force with the running driving force source when the fail-down shift detecting means (step 5) detects the variable speed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for controlling switching of a shift range, a shift speed, and the like in an automatic transmission for a vehicle.

[0002]

2. Description of the Related Art As is well known, an automatic transmission for a vehicle is configured to execute a shift based on a running state of the vehicle such as a vehicle speed and a throttle opening, and a shift that can be set during forward running. The stage is configured to be selected by switching the traveling range. This shift range is a shiftable region in which the presence or absence of a limit of a settable gear (gear ratio) and the presence or absence of an engine braking state at a predetermined gear are different. Thus, the shift range is selected.

On the other hand, Japanese Patent Laying-Open No. 5-196118 discloses an apparatus capable of switching a gear range by operating an electric switch. In the device described in this publication, an up switch and a down switch are made operable by an enable switch, and in this state, the up switch is turned on to set the shift range to the one-step high-speed range. When the down switch is turned on, the shift range is switched to the one-step lower speed range.

[0004]

The shift range on the low speed side is selected when a large driving force is obtained or when the engine brake is applied, and the settable shift speed is limited to a predetermined middle speed range. In addition, the engine brake can be applied at any of these settable gears. Therefore, if the shift range is switched to the middle / low speed range, a downshift may occur at the same time. An automatic transmission that can switch this kind of shift range by electrical control is configured to be able to set the gear position by electrical control. For example, incorporating multiple solenoid valves into a hydraulic control device,
By controlling ON / OFF of these solenoid valves, the supply path of the hydraulic pressure is changed, and thereby the shift speed is set.

[0005] Therefore, in such an automatic transmission, when an electric failure occurs, the ON / OFF state of one of the solenoid valves is switched, and there is a possibility that a shift to a gear position where engine braking is effective may occur. When the engine brake is applied in association with such a shift, deceleration due to a failure may cause a sense of incongruity. However, the invention described in the above publication includes means for coping with such a situation. Absent.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a control device capable of preventing or reducing an uncomfortable feeling of deceleration caused by a failure.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, according to the first aspect of the present invention, there is provided an automatic transmission in which a low speed side gear ratio at which an engine brake works can be set by electric control. However, in a control device of a vehicle with an automatic transmission connected to a driving power source for driving, a fail-down detecting that a shift from a high-speed gear ratio to a low-speed gear ratio in which the engine brake works is caused by a failure. A shift detecting means, and a braking force reducing means for reducing a braking force by the driving power source for driving when the fail down shift detecting means detects the shift.

According to a second aspect of the present invention, in the first aspect of the present invention, the driving power source for driving comprises an internal combustion engine having an electrically controllable throttle valve, and the braking force reducing means includes A throttle opening control means for increasing the opening of the throttle valve is provided.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the driving power source for driving comprises an internal combustion engine capable of electrically controlling the supply and cutoff of fuel, and the braking force is reduced. The means includes fuel control means for stopping the shutoff of the fuel and supplying the fuel.

Therefore, according to these inventions, when the gear ratio increases and the state in which the engine brake works is caused by a failure, the braking force by the driving power source for traveling is reduced. Therefore, since the energy consumed for forcibly driving the driving power source for traveling is reduced,
Engine braking force decreases. That is, since the braking action is reduced or eliminated, it is possible to avoid or reduce the unnatural feeling of deceleration caused by the failure.

According to the second aspect of the present invention, the braking effect of the throttle valve of the internal combustion engine, which is the driving power source for driving, is reduced by increasing the opening of the throttle valve. A certain feeling of deceleration can be avoided. In this case, it is not necessary to increase only the opening of the throttle valve and increase the fuel supply amount.

According to the third aspect of the present invention, when the fuel supply to the internal combustion engine is shut off, the supply of the fuel is restarted. Therefore, an uncomfortable feeling of deceleration can be easily avoided by using the existing device.

[0013]

Next, the present invention will be described more specifically with reference to the drawings. First, an overall control system will be described. FIG. 3 shows a control system diagram of an engine 1 and an automatic transmission 2 as an example of a driving power source for traveling, and shows a control system diagram corresponding to a depression amount of an accelerator pedal 3. The signal is input to the engine electronic control unit 4. A throttle actuator 5 is provided in the intake pipe of the engine 1.
There is provided an electronic throttle valve 6 driven by. The electronic throttle valve 6 outputs a control signal from the electronic control unit 4 to the throttle actuator 5 according to the amount of depression of the accelerator pedal 3, and the opening is controlled according to the control amount. In this case, the opening degree characteristic of the electronic throttle valve 6 with respect to the amount of depression of the accelerator pedal 3 can be changed. Therefore, even when the amount of depression of the accelerator pedal 3 does not change, the opening of the electronic throttle valve 6 can be changed. The degree can be changed.

An electronic control unit 4 for controlling the engine 1 includes a central processing unit (CPU) and a storage unit (R).
AM, ROM) and an input / output interface. The electronic control unit 4 includes, in addition to a signal corresponding to the depression amount of the accelerator pedal 3 described above,
Engine speed Ne, intake air amount Q, intake air temperature,
A throttle opening, a vehicle speed, an engine water temperature, an output signal of a brake switch, and the like are input as control data. In addition to the control of the throttle actuator 5, the engine electronic control unit 4 supplies and supplies fuel.
A signal is output to a fuel injection device 7 for shutoff and adjustment of a supply amount, an igniter 8 for changing an ignition timing for torque control at the time of gear shifting, and the like.

The automatic transmission 2 connected to the engine 1 is a so-called electronically controlled automatic transmission that electrically controls the hydraulic pressure to control shifting and engagement / disengagement of a lock-up clutch. The hydraulic control device 9 for controlling the hydraulic pressure mainly includes three shift solenoid valves SOL1, SOL2, SOL3 for executing a shift, and a solenoid valve SOL4 for mainly controlling an engine braking state.
A linear solenoid valve SLU that mainly controls the lock-up clutch, a linear solenoid valve SLT that controls the line pressure according to the throttle opening, and a linear solenoid valve SLN that mainly controls the back pressure of the accumulator.

An electronic control unit 10 for an automatic transmission for outputting a control signal to each solenoid valve in the hydraulic control unit 9 is provided. The electronic control unit 10 for the automatic transmission is similar to the electronic control unit 4 for the engine described above.
Central processing unit (CPU) and storage device (RAM,
ROM) and an input / output interface, and therefore can be integrated with the engine electronic control unit 4 as needed. The electronic control unit 10 for the automatic transmission performs a calculation based on input data in accordance with a map or a calculation formula stored in advance, and outputs a control signal based on the calculation result to each of the solenoid valves to shift or lock up. It is configured to execute control of engagement / disengagement of a clutch, control of transient hydraulic pressure during gear shifting, and the like.

The electronic control unit 10 for the automatic transmission includes the above throttle opening, vehicle speed,
In addition to the engine water temperature and the output signal of the brake switch,
A shift position indicating a position of a shift lever as a first range operating mechanism, an output signal of a pattern select switch, an output signal from a C0 sensor for detecting a rotation speed of a clutch C0 described later, and a rotation speed of a second clutch C2 are detected. Output signal of C2 sensor, oil temperature of automatic transmission 2, output signal of manual shift switch, cut signal for shifting shift range to low speed, cut-off signal for shifting shift range to high speed, cruise control to keep vehicle speed constant A cruise signal output from a device (not shown), a signal from a main switch SM for activating a cut signal and a cutoff signal, and the like are input. Further, the electronic control unit 10 for the automatic transmission includes a shift lever position indicator 11 for displaying the position of the shift lever and a shift range indicator 12 for displaying the selected shift range.
And are connected.

The electronic control units 4 and 10 are connected so as to be able to communicate with each other. In particular, the electronic control unit 10 for the automatic transmission transmits a signal to the electronic control unit 4 for the engine to set each gear. Is transmitted from the engine electronic control unit 4 to the automatic transmission electronic control unit 10 (Q / N).
e) has been sent.

The above-mentioned automatic transmission 2 has five forward speeds and one reverse speed.
The gear stage can be set, and an example of the gear train is shown in FIG. In FIG. 4, the automatic transmission 2
Is connected to the engine 1 via a torque converter 13. The torque converter 13 includes a pump impeller 15 connected to a crankshaft 14 of the engine 1 and a turbine runner 1 connected to an input shaft 16 of the automatic transmission 2.
7, the pump impeller 5 and the turbine runner 17
And a stator 20 that is prevented from rotating in one direction by a one-way clutch 19.

The automatic transmission 2 has a high and a low 2
The vehicle is provided with an auxiliary transmission section 21 for switching gears, and a main transmission section 22 for switching between reverse gear and four forward gears.
The auxiliary transmission unit 21 is composed of a planetary gear unit 23 composed of a pinion P0 rotatably supported by the sun gear S0, the ring gear R0, and the carrier K0 and meshed with the sun gear S0 and the ring gear R0. It has a clutch C0 and a one-way clutch F0 provided therebetween, and a brake B0 provided between the sun gear S0 and the housing 29.

The main transmission section 22 includes a first planetary gear set 24 comprising a sun gear S1, a ring gear R1, and a pinion P1 rotatably supported by the carrier K1 and meshed with the sun gear S1 and the ring gear R1.
A second planetary gear set 25 comprising a pinion P2 rotatably supported by the sun gear S2, the ring gear R2, and the carrier K2 and meshed with the sun gear S2 and the ring gear R2; a sun gear S3, a ring gear R3;
And a third planetary gear set 26 comprising a pinion P3 rotatably supported by the carrier K3 and meshed with the sun gear S3 and the ring gear R3.

The sun gear S1 and the sun gear S2 are integrally connected to each other, and the ring gear R1, the carrier K2, and the carrier K3 are integrally connected to each other.
Is connected to the output shaft 27. Also, the ring gear R2
Are integrally connected to the sun gear S3. A first clutch C1 is provided between the ring gear R2 and the sun gear S3 and the intermediate shaft 28, and a second clutch C2 is provided between the sun gear S1 and the sun gear S2 and the intermediate shaft 28.

A first brake B1 in the form of a band for stopping rotation of the sun gear S1 and the sun gear S2 is provided on the housing 29 as braking means. The sun gear S1 and the sun gear S2 and the housing 29
Between the first one-way clutch F1 and the brake B
2 are provided in series. This first one-way clutch F
1 is configured to be engaged when the sun gear S1 and the sun gear S2 try to reversely rotate in the direction opposite to the input shaft 6.

A third brake B3 is provided between the carrier K1 and the housing 29, and a fourth brake B4 and a second one-way clutch F2 are provided between the ring gear R3 and the housing 29 in parallel. Have been. This second
The one-way clutch F2 is configured to be engaged when the ring gear R3 attempts to rotate in the reverse direction. The clutches C0, C1, C2, the brakes B0, B1, B2
, B3, B4 are hydraulic friction engagement devices in which friction materials are engaged by the action of hydraulic pressure.

The clutch C0 in the sub-transmission 23
And a C2 sensor 31 for detecting the number of revolutions of the second clutch C2 in the main transmission portion 22. In addition,
These sensors 30 and 31 are connected to the electronic control unit 10 for the automatic transmission as described above.

In the automatic transmission 2 described above, five forward speeds and reverse speeds can be set, and the engagement / disengagement state of each friction engagement device for setting these shift speeds is shown in FIG. This is shown in the engagement operation table. In FIG. 5, the mark ○ indicates the engaged state, and the mark ◎ indicates that the engagement does not affect the torque transmission.
● indicates that the engine is engaged to apply the engine brake, and blank indicates the released state.

A hydraulic circuit shown in FIG. 6 is provided in the hydraulic control device 9 for setting the respective shift ranges and shift speeds shown in FIG. That is, the manual valve 40 that receives the supply of the line pressure PL according to the throttle opening degree
And between the hydraulic servo means of each friction engagement device described above,
Controlling the supply and discharge of the control pressure PC to and from the fourth brake B4 for the first speed engine brake 1-2 Control the supply and discharge of the drive range pressure PD to the second brake B2 for achieving the third speed and the second shift valve 41 2 -3 shift valve 4
Supply and discharge of control pressure PC to first brake B1 for second and third speed engine brakes, and drive range pressure PD to second clutch C2 for fourth and fifth speeds
3-4 shift valve 43, brake B
A 4-5 shift valve 44 for switching the supply of the line pressure PL to the clutch C0 and the clutch C0 is provided.

Further, drive range pressure (D range pressure)
A pressure control valve 45 that generates a control pressure PC by adjusting a signal pressure output from a linear solenoid valve SLN during gear shifting during a gear shift, and an engine brake relay valve that switches supply and discharge of a control pressure PC to a 2-3 shift valve 42. 46, a C0 exhaust valve 47 for switching the supply and discharge of the line pressure PL to and from the clutch C0 via the 4-5 shift valve 44 is provided.

The first shift solenoid valve SOL1
Outputs a signal pressure for switching the 2-3 shift valve 42, and the second shift solenoid valve SOL2 outputs the 1-2 shift valve 4
The third switching solenoid valve SOL3 outputs the switching signal pressure to the C0 exhaust valve 47 via the 1-2 shift valve 41. The fourth solenoid valve SOL4 is connected to the engine brake relay valve 46 and the C0 exhaust valve 4
7 and the linear solenoid valve SLN outputs a signal pressure for pressure adjustment to the pressure control valve 45. Further, an accumulator is attached to the friction engagement devices other than the first brake B1 and the fourth brake B4.

The configuration and function of each of the above components will be described in more detail. The manual valve 40 is connected to a shift lever as a mechanical shift range switching mechanism (not shown) by mechanical means such as a cable, and interlocks with the shift lever. The line pressure PL is supplied from an input port 48, and the spool 4 is provided with a spool valve.
According to the sliding position of No. 9, the input port 48 is connected to each output port for output. Specifically, in the D position, the signal is output only from the D range port 50, in the "3" position, the signal is output from the "3" range port 51, and in the "2" position, the signal is output from the "2" range port 52. In the L position, the signal is further output from the L range port 53. On the other hand, in the R position, the signal is output from the R range port 54, in the N position, all output ports are closed, and in the P position, the input port 48 is connected to the drain port EX.
In the automatic transmission 2 described above, the "4" range can be selected. This is a shift range in which the fifth speed, which is the highest speed, is prohibited. It turns around the center and the above "2"
Oil pressure is output from range port 52.

Next, the pressure control valve 4
5 has a spool and a plunger pressed in one direction by a spring, receives a D range pressure PD, and regulates the pressure by an output signal of a linear solenoid valve SLN.
Control pressure PC is applied to engine brake relay valve 4
Via 6, it is supplied to the 2-3 shift valve 42.

The engine brake relay valve 46 is a switching valve having a spool and a plunger pressed in one direction by a spring. When the "2" range pressure is applied to the plunger, the signal of the linear solenoid valve SLN is output. Pressure is applied to the spool, and
-3 supply of control pressure PC to shift valve 42;
The discharge of the control pressure PC from the 2-3 shift valve 42 by the release of the oil pressure is switched.

The 2-3 shift valve 42 is a switching valve provided with a spool pressed in one direction by a spring.
The supply of the control pressure PC to the 3-4 soft valve 43 and the 1-2 shift valve 41 is switched by application of the signal pressure and the L range pressure of the shift solenoid valve SOL1,
In addition, communication of the D range pressure PD to the oil passages L1a and L1b and switching of drains are performed.

The 1-2 shift valve 41 is a switching valve provided with a spool pressed in one direction by a spring.
Signal pressure of shift solenoid valve SOL2 and oil passage L1a
Supply of the control pressure PC to the fourth brake B4 and switching to exhaust pressure from the brake B4, and supply of the signal pressure of the third shift solenoid valve SOL3 to the oil passage LS32 and its oil passage LS32 And switching from discharge to

The 3-4 shift valve 43 is a switching valve provided with a spool pressed in one direction by a spring via a piston. The signal pressure of the second shift solenoid valve SOL2, the oil pressure from the oil passage L1b, and the oil pressure The third shift solenoid valve SOL3 from the oil passage LS3 is operated by the hydraulic pressure from the passage L3.
Supply and cutoff to the 4-5 soft valve 44 via the oil passage LS34, communication and cutoff of the oil passage L1a to the oil passage L1e, supply of the control pressure PC to the first brake B1 and its brake B1 To control the pressure from the exhaust.

The 4-5 shift valve 44 is a switching valve provided with a spool pressed in one direction by a spring. The signal pressure from the oil passage LS34 and the oil pressure in the oil passage L2 make the C0 exhaust valve of the line pressure PL. Switching between supply and discharge to 47 and control of supply to brake B0 via oil passage LL1 and discharge from brake B0 are controlled.

The C0 exhaust valve 47 includes a spool 55 and a plunger 56 which are pressed in one direction by a spring.
And a 4-5 shift by the signal pressure of the fourth solenoid valve SOL4 via the oil passage LS4, the signal pressure of the third solenoid valve SOL3 via the oil passage LS32, and the oil pressure of the oil passage L1d. Line pressure P via valve 44
L is supplied to the clutch C0 via the oil passage LL3 and discharged from the clutch C0.

In the hydraulic control device configured as described above, in the illustrated neutral position, the line pressure PL is supplied to the clutch C0 via the 4-5 shift valve 44 and the C0 exhaust valve 47. Since the oil passage passing through the valve 40 is shut off, the hydraulic pressure of the first clutch C1 is drained. The deviation of the position sandwiching the center line of each valve in the figure is
This indicates the limit position of the spool displacement. In particular, for each shift valve, the position and the shift speed are made to correspond to each other by dividing numbers on the left and right of the center line.

According to the hydraulic control device described above, the range pressure is controlled by electronic control corresponding to the vehicle speed and the engine load (for example, the throttle opening) in accordance with the selection of the position of the manual valve 40 due to the manual operation of the shift device. Pressure adjustment and shift solenoid valves SOL1 and SOL3 are ON
/ OFF control is performed to set each shift speed. That is, each clutch and brake are controlled as shown in FIG. 5 to set each shift speed in relation to the one-way clutch (OWC), and to turn ON / OF the fourth solenoid valve SOL4.
Engine (E / G) by output of the signal pressure accompanying F
The braking state can be obtained.

For example, when the signal pressure is output from the fourth solenoid valve SOL4 in the state where the third speed is set in the D range, the spool of the engine brake relay valve 46 is moved to the position shown in the left half of FIG. , As a result, D
The control pressure PC based on the range pressure is supplied to the 3-4 shift valve 43 via the 2-3 shift valve 42,
From here, the hydraulic pressure is supplied to the first brake B1, which is engaged. That is, the engine brake is activated in the third speed.

When the fourth solenoid valve SOL4 outputs a signal pressure in the second speed state of the D range, hydraulic pressure is supplied to one end of the spool of the C0 exhaust valve 47. Then, the line pressure PL supplied via the 4-5 shift valve 44 is supplied to the clutch C0 in the auxiliary transmission section 21 and the clutch C0 is engaged to apply the engine brake at the second speed. it can.

Further, when the fourth solenoid valve SOL4 outputs a signal pressure at the first speed in the D range, the signal from the engine brake relay valve 46 is transmitted similarly to the case of the third speed described above.
The control pressure PC is output to the 2-3 shift valve 42, and the control pressure PC is supplied from the 2-3 shift valve 42 to the 1-2 shift valve 41, from which the control pressure PC is sent to the fourth brake B4. Combine. That is, the engine brake can be applied at the first speed.

Each of the first to fifth speeds is defined by:
First to third shift solenoid valves SOL1,.
OL3 is controlled by ON / OFF control as shown in FIG. 7 and the shift pressure is set by appropriately switching the shift valves 41 to 44 according to the output pressure. It is easily known from hydraulic circuits.

As described above, in the automatic transmission 2 described above, each shift speed can be electrically controlled and set.
The engine brake at the lower gear speed can be set by electrically controlling the fourth solenoid valve SOL4. Utilizing such a function, the range control device according to the present invention is configured to electrically switch each forward range.

FIG. 8 shows an example of a range operating mechanism for electrically switching the forward range, that is, an electric shift range switching mechanism. In FIG. 8, reference numeral 60 denotes a steering wheel (handle), and a second shift lever 61 is attached to a steering column (not shown) to which the steering wheel 60 is attached. The second shift lever 61 is disposed protruding from the steering column in a radial direction at a position close to the steering wheel 60, and has a length that can be operated by a finger of the hand holding the steering wheel 60. I have. The second shift lever 61 is held by an elastic force so as to be always located at the neutral position.
The steering column can be rotated in the radial direction from the neutral position and can be pulled toward the steering wheel 60.

The rotation operation of the second shift lever 61 in the circumferential direction is an operation for raising and lowering the speed change range, and switches 62 and 63 for detecting the operation are provided. Each of these switches 62 and 63 is a so-called momentary switch that outputs a signal each time the switch is turned on, and among them, a position rotated counterclockwise in FIG. 8 with respect to the neutral position of the second shift lever 61. Is a cut-off switch that outputs a signal for switching the shift range to a high speed side (up range), and a switch 63 located on the opposite side switches the shift range to a low speed side (down). This is a cut switch that outputs a signal for the range.

The cut-off switch 62 and the cut switch 63 are connected to the above-described electronic control unit 10 for an automatic transmission. These switches 62,
Reference numeral 63 is configured to be activated by the main switch SM in a state where the D range is set by a shift lever of a shift device (not shown), that is, to be in a state capable of outputting an electric signal. In particular,
The main switch SM is a momentary switch, and each time the main switch SM is turned ON once, the cutoff switch 62 and the cut switch 63 are switched between an active state and an inactive state.

Further, the operation of pulling the second shift lever 61 toward the steering wheel 60 cancels the electrically set shift range by rotating the second shift lever 61 in the circumferential direction of the steering column as described above. Then, a return switch 65 for detecting such an operation of the second shift lever 61 is provided. The return switch 65 is connected to the electronic control unit 10 for the automatic transmission, and inputs a signal accompanying the return operation of the second shift lever 61 to the electronic control unit 10 for the automatic transmission. Note that the arrangement position and operation direction of the second shift lever 61 are shown in an enlarged manner in FIG.

Further, there is provided a mechanism for executing switching of two or more speed ranges in one operation. That is, the second shift lever 61 is further configured to rotate from its neutral position in a direction away from the steering wheel 60, and is turned on by such a rotating operation.
An operated double cut switch SDC is provided. The double cut switch SDC is connected to the electronic control unit 10 for the automatic transmission, and outputs a signal by being turned on by the second shift lever 61. Based on the output signal, the double cut switch SDC is two steps lower than the current shift range. It is configured to switch to the speed change range.

When the shift range is switched by operating the second shift lever 61, the manual valve 40
It can be executed when it is in the range position, that is, when the D range is selected by the shift device that mechanically selects the shift range, and when it is activated by operating the main switch SM, Cut switch 63
Alternatively, when the cutoff switch 62 or the double cut switch SDC outputs a signal, the shift range is controlled down or up. The downshift or upshift control of the shift range is executed by switching the shift range to the one-stage or two-stage low-speed side or switching to the high-speed side shift range with respect to the current shift range. Every time the signal is output once, that is, every time the second shift lever 61 is rotated clockwise once, the order is D range → “4” range → “3” range → “2” range → L range. The range is switched, and conversely, each time the cutoff signal is output once, that is, every time the second shift lever 61 is rotated counterclockwise once, the L range → “2” range → “3”. The range is switched in the order of “4” range → D range.

In each of these shift ranges, a settable shift speed and a shift speed at which the engine brake works are determined, and these shift speeds are stored in the electronic control unit 10 in advance as a map. In addition, an ON / OFF pattern of a solenoid valve for applying an engine brake is stored. Each time the cut switch 63 or the cut-off switch 62 is turned on, the shift map and the solenoid pattern are changed, and a predetermined shift range is set. In this case, in the state of the D range, there is no more high speed side shift range, so that the output signal due to the ON operation of the cutoff switch 62 is cancelled. Since there is no range, the output signal due to the ON operation of the cut switch 63 is canceled.

Further, when the shift range is switched to a lower-speed shift range, a downshift may occur at the same time, in which case the engine speed increases. Therefore, in order to protect the engine 1, when the cut switch 63 is turned ON in a state where overrun or overrevolution occurs in the engine 1, its output signal is canceled and the current shift range is maintained. . This is the same control as the down range prohibition control in the conventional shift device.

Further, when the return switch 65 is turned on, the manual valve 40 is mechanically moved to set the selected D range. This means that the shift map for controlling the shift range is switched to that for the D range, and the solenoid valve is turned on according to the map.
This is executed by performing N / OFF control.

Therefore, according to the range control device configured as described above, the second shift lever 6 having the shift range for forward running provided near the steering wheel 60 is provided.
1, the shift range can be changed without releasing the hand from the steering wheel 60 and keeping the line of sight facing forward, thereby improving the operability of changing the shift range. I do. In particular, the D range can be set immediately by turning on the return switch 65 with the second shift lever 61, so that the cutoff switch 62 is turned on a plurality of times to return to the D range.
The return to the D range can be easily performed, and in that respect, the operability of the range operation is also improved.

In a vehicle equipped with a cruise control system for maintaining a constant vehicle speed, when the second shift lever 61 is operated to select the "4" range, the cruise control system is activated. Let
Further, the shift range on the lower speed side is set to the second shift lever 6.
If the gear is operated by operating the gear 1, the function of the cruise control system is canceled. This is because the control of the vehicle speed and the shift speed are superimposed.

As described above, in the range operating device according to the present invention, the shift between the forward ranges is performed by the electric operating device, and the electric range operation is performed by setting the manual valve 40 to the D range. It is possible in the state where it is done. Therefore, the switch for shifting between the forward ranges is not necessarily required to be performed by the second shift lever 61, and the manual valve 40 is not necessary.
May be configured to include only the D range position as the range position for forward traveling. The example shown in FIG. 9 is configured in consideration of these points.

That is, in the configuration shown in FIG. 9, a first shift lever 66 connected to the manual valve 40 by mechanical means such as a cable is provided on the steering column so as to protrude in the radial direction. The first shift lever 66 is configured to be rotated in the circumferential direction of the steering column to switch the manual valve 40, similarly to a lever in a so-called conventional column-type shift device. In the example shown in FIG. 9, the first shift lever 66 has four positions, parking (P), reverse (R), neutral (N), and drive (D).
Only one range position is provided, and these range positions are arranged counterclockwise in the order listed here, as shown in FIG. Note that it is optional to configure so that a shift button (not shown) needs to be pressed between the P range and the R range and between the R range and the N range.

A cut-off switch 62 and a cut switch 63 for electrically switching the shift range in the D range are arranged at a position near the center of the steering wheel 60. These switches 62 and 63
Is constituted by a momentary push button switch and may be attached to the steering wheel 60. However, it is preferable that the position is not changed by the rotation of the steering wheel 60 by attaching to the steering column. .

In the configuration shown in FIG. 9, not only the same effect as that obtained by the device having the configuration shown in FIG. 8 can be obtained, but also the shift conventionally arranged beside the driver's seat. Since the device can be eliminated, the degree of freedom in arranging other in-vehicle devices is improved. Further, the first shift lever 66 is located on the front side of the steering wheel 60, but the range positions selected by the first shift lever 66 are the four range positions described above.
The driver's line of sight and front view with respect to the meter panel (not shown) and the center cluster are less obstructed by the first shift lever 66, so that the visibility can be prevented from deteriorating. By shortening the length within the allowable range, the visibility of the center cluster and the like can be improved.

As described above, the first shift lever 66 for switching the manual valve 40 by mechanical operation is mainly operated at the start of traveling, and the change of the shift range during traveling is mainly performed by the second shift lever 61.
Or cut-off switch 62 or cut switch 63
Is performed by operating. Therefore, the shift lever for selecting the P range, the R range, or the like by mechanical operation is only required to be able to select the minimum necessary shift range, and the position of the shift lever is the same as that of a conventional general vehicle. It may be on the side floor or on the instrument panel.

FIG. 10 schematically shows an example of a so-called gate type shift lever arranged on a floor or an instrument panel.
The shift positions of the N range, the D range, the “3” range, and the L range are arranged in this order from the front side of the vehicle.
Alternatively, they are arranged as shown in FIG. 10 from above.
The solid line connecting the shift positions in FIG. 10 indicates a guide groove for moving the shift lever.
In a case where a so-called sport mode in which each gear is set by manual operation can be selected, FIG.
A shift position for the sports mode may be set at a location where (Sport) is described. When the shift range is switched by an electric operation, the first shift lever 66 needs to be set to the D range position.
"E" (Electroni) with "D" displayed at the range position
The display of c) may be added in advance.

FIG. 11 shows an example in which the "3" range position is eliminated from the configuration shown in FIG. 10, and the shift to the L range which is the engine brake range is selectively prohibited. . That is, the forward range can be selected by the second shift lever 61, the cut-off switch 62, or the cut switch 63 described above.
Further, range operation by these electric operation mechanisms is easy. Therefore, in a shift device that mechanically selects a shift range, it is sufficient that the D range can be selected as the forward range, and another engine brake range can be selected as a measure against failure. For this reason, in the example shown in FIG.
A lock mechanism GS such as a pin is provided in the guide groove so that the shift lever does not move to the range (R), and by operating the fail switch SF disposed at an appropriate position, the lock mechanism GS is opened to shift the shift lever to the L range. It is configured to be able to move to a position. The fail switch SF and the shutoff mechanism GS may be electrically connected, or may be connected by mechanical means such as a link.

Further, a cut-off switch 62 for outputting a signal for an up-range and a cut switch 63 for outputting a signal for a down-range include a front surface (a surface facing the driver) and a rear surface (a surface facing the driver) of the steering wheel 60. (The side facing the instrument panel). An example thereof is schematically shown in FIG. 12, and a cut-off switch 62 indicated by a plus sign surrounded by a dashed circle is provided on the back of the steering wheel 60, and a cut switch 63 indicated by a minus sign surrounded by a solid circle. Is provided in front of the steering wheel 60. With such a configuration, the shift range switching operation can be performed by the thumb and the index finger of the hand holding the steering wheel 60. In this case, eight ranges shown in FIG. 5 can be provided as the shift ranges, and the arrangement of these range positions in the shift device may be the same as the arrangement in the conventional shift device.

In the automatic transmission 2 described above, the first to third
Each of the forward gears is set by ON / OFF control of the solenoid valves SOL1 to SOL3 of FIG. 7 as shown in FIG. 7, and the engine brake state at the first to third speeds by controlling the ON of the fourth solenoid valve SOL4. It is said. Therefore, when the cut switch 63 is operated to set the engine brake range, the first to third solenoid valves SOL1,.
If 3 fails, there may be a shift to a lower gear where the engine brake works. For example, as shown in FIG. 7, in the second speed, the second solenoid valve SOL2 is turned on. However, if the second solenoid valve SOL2 fails due to disconnection or the like, a downshift to the first speed occurs.
In that case, the fourth solenoid valve SOL4
Is turned on to apply the engine brake, the engine brake is effective even in the first speed after the downshift, which causes a sense of discomfort. In order to prevent such an uncomfortable feeling of deceleration, the control device of the present invention is configured to execute the control described below.

FIG. 1 is a flowchart for explaining an example of the control. First, processing of an input signal mainly for reading data (step 1) is performed, and then a mechanical shift range switching mechanism is performed. D by shift device
It is determined whether a range has been selected (step 2). The automatic transmission of interest in this embodiment is driven by the first shift lever, which is a mechanical range switching mechanism.
This is because the shift range can be switched by an electrical operation in a state where the range is set. The determination in step 2 can be made based on an output signal from a shift position sensor provided in the shift device.

If a negative determination is made in step 2 because a shift range other than the D range has been set, this routine is exited without performing any particular control, and conversely, an affirmative determination is made in step 2. In this case, it is determined whether or not the cutting control is being performed (step 3). This cut control is a state in which the shift range is set to the engine brake range by the electric range switching mechanism. Specifically, the main switch SM is turned on to operate the cutoff switch 63 and the cut switch. 62 is activated (active), and in this state, a predetermined engine brake range is set by the cut switch 63 or the cut-off switch 62. This decision
This can be performed based on the set gear position and the operation (energization) state of the fourth solenoid valve SOL4.

Step 3 because the cut control is not being performed
If the determination is negative, the routine exits from this routine without performing any particular control. Conversely, if the determination is affirmative, it is determined whether or not the "2" range is set (step S1). 4). The range determined here is a shift range that is set electrically. Therefore, the input state of a signal from the cut switch 63 or the cutoff switch 62 to the electronic control device 10 or the electronic control device 10 that is executed in accordance with the input state. Can be determined based on the output state of the signal by The “2” range is the second
This is a shift range that can be upshifted to the first speed and is set in a state where the second speed is effective with the engine brake.

If the shift range set by the electrical control is a shift range other than the "2" range and a negative determination is made in step 4, the routine exits without performing any particular control. On the other hand, if a positive determination is made, a failure determination is made (step 5). The failure determined here is a failure that causes a discrepancy between the speed at which the control is being executed and the speed that is actually set, and accordingly, the second failure that should be in the ON state.
The solenoid valve SOL2 is in the OFF state, or the speed ratio calculated from the input speed (NCO) of the automatic transmission 2 and the output shaft speed is different from the speed ratio of the second speed. It can be determined by such as. Step 5 corresponds to the fail downshift detecting means of the present invention.

If a negative determination is made in step 5 because such a failure is not detected, the routine exits without performing any particular control. Conversely, if the result of the above-mentioned failure is affirmative in step 5, control to increase the opening of the electronic throttle valve 6 is executed (step 6). When the electronic throttle valve 6 is closed, the intake air is restricted, so that a resistance acts on the rotation of the engine 1 and this becomes an engine braking force. Therefore, when the engine is downshifted to a low speed stage where engine braking is effective due to a failure, the opening degree of the electronic throttle valve 6 is increased to promote intake and thereby reduce the engine braking force. Therefore, step 6 corresponds to the braking force reducing means in claim 1 or the throttle opening control means in claim 2. In this case, the opening degree of the electronic throttle valve 6 is increased in order to reduce the intake resistance. Therefore, although the electronic throttle valve 6 is opened, fuel is not supplied (injected).

It is determined whether fuel cut is being performed (step 7). When the vehicle is decelerated, the engine 1 is rotated by the traveling inertia force, and if the rotation speed is equal to or higher than a predetermined return rotation speed, the rotation of the engine 1 can be maintained even if the fuel is cut off until the return rotation speed is reached. Therefore, the fuel supply may be stopped (fuel cut) at the time of deceleration in order to improve fuel efficiency. In step 7, it is determined whether or not this control is being executed. This is, specifically,
The determination can be made based on a signal input from the engine electronic control device 4.

If an affirmative determination is made in step 7 because the fuel is being cut, this is stopped and fuel injection in the engine 1 is restarted (step 8). Therefore, since the engine 1 outputs power according to the fuel supply amount, the engine output changes from negative to positive, and the engine braking state is eliminated or reduced. In addition,
This step 8 corresponds to the braking force reducing means in claim 1 or the fuel control means in claim 3.

Further, upshift control to the third speed is executed (step 9). In this embodiment, specifically, the first solenoid valve SOL1 is turned off. In this case, the failure causes the second solenoid valve SOL2 to
Since it is in the FF state, the first solenoid valve SOL
1 is controlled to OFF, as is known from FIG.
The speed will be set. As a result, the gear ratio becomes smaller, so that the deceleration becomes smaller even when the engine is in the brake state. If a negative determination is made in step 7 because the fuel is not being cut,
The process immediately proceeds to step 9 to execute the upshift control.

If the above-described control of the engine output due to the occurrence of a failure is executed after downshifting due to the failure, a feeling of acceleration due to an increase in engine output occurs after a feeling of deceleration due to the downshift. The output control is preferably performed before the downshift is performed. For this purpose, for example, an orifice Of may be provided immediately before the fourth brake B4 in the hydraulic circuit shown in FIG. Alternatively, as shown in FIG. 2, at the time of engine braking at the reverse speed and the first forward speed (L range)
When the hydraulic pressure is supplied from the manual valve 40 and the 1-2 shift valve 41 via the shuttle valve VS to the fourth brake B4 engaged with the An orifice Of may be provided between 41 and the shuttle valve VS.

With such a configuration, when a downshift from the second speed to the first speed occurs in the engine brake range set by the electric control, the engine brake must be activated at the first speed. Hydraulic pressure is slowly supplied to the engaged fourth brake B4, and the time required to achieve the first speed in the engine braking state becomes longer. Therefore, by performing the above-described control of the engine output during that time, the engine braking force at the time of downshifting can be suppressed low, and the occurrence of a feeling of acceleration following a feeling of deceleration can be prevented. In particular, in the case of the configuration shown in FIG. 2, when the reverse gear is set, the hydraulic pressure can be supplied to the fourth brake B4 without passing through the orifice Of, so that there may be a delay in achieving the reverse gear. Absent.

Since the upshift control in step 9 described above is a control for reducing the torque amplifying effect of the automatic transmission 2, it may be replaced with another control having the same effect, or may be replaced with another control. Control may be used together. For example, the clutch C in the sub-transmission 21 described above
0 may be released to interrupt the transmission of torque between the engine 1 and the automatic transmission 2, or the pressure regulating valve for engine braking may be locked to release the engine braking state.

The above-described controls in steps 6, 8, and 9 are as follows.
In either case, the control acts to reduce the engine braking force, and the same applies to the release of the clutch C0, which is mentioned as the control in place of the upshift in step 9.
Therefore, if the engine braking force associated with the failure can be reduced to a necessary and sufficient degree by any of these controls, any one of the controls may be executed without performing all of these controls, or a plurality of controls may be performed. May be appropriately combined and executed.

Further, in the above-described embodiment, the case of downshifting to the first speed has been described as an example. However, the present invention is similarly applied to the case of a fail that causes a downshift to another speed. be able to. In the above embodiment,
Although the description has been given of a vehicle that uses the engine 1 as a driving power source for traveling and uses a stepped transmission as an automatic transmission, the present invention relates to a motor or a motor and an internal combustion engine that are connected to a driving power source for traveling. The present invention can be similarly applied to a control device for a vehicle equipped with a continuously variable automatic transmission. The present invention can be applied to an automatic transmission having a gear train or a hydraulic circuit other than the gear train shown in FIG. 4 or the hydraulic circuit shown in FIG.

[0078]

As described above, according to the first to third aspects of the present invention, when a downshift occurs in the engine braking state due to a failure, the braking force by the driving power source for driving connected to the automatic transmission is reduced. Since it is reduced, it is possible to effectively prevent a sense of discomfort caused by the failure.

[Brief description of the drawings]

FIG. 1 is a flowchart for explaining a control example executed by a control device of the present invention.

FIG. 2 is a schematic partial hydraulic circuit diagram showing an example in which an orifice for delaying the supply of hydraulic pressure to a brake to be engaged when applying an engine brake at a first speed is provided.

FIG. 3 is a diagram schematically showing an overall control system of the automatic transmission targeted by the present invention.

FIG. 4 is a skeleton diagram showing an example of a gear train of the automatic transmission according to the present invention.

FIG. 5 is a table showing an engaged / disengaged state of a friction engagement device for setting each shift speed.

FIG. 6 is a partial hydraulic circuit diagram showing a part of a hydraulic circuit of an automatic transmission according to the present invention.

FIG. 7 is a table showing ON / OFF states of a shift solenoid valve for setting each forward speed.

FIG. 8 shows a second range operation mechanism according to the present invention;
It is a figure which shows arrangement | positioning of a shift lever, (A) is the figure seen from the front of a steering wheel, (B) is the elements on larger scale of the 2nd shift lever, (C) is the figure seen from the side of the steering wheel. is there.

FIG. 9 shows a first range operation mechanism according to the present invention, ie, a first range operation mechanism.
FIG. 4 is a front view of an example in which a shift lever is arranged on a steering column, and a cutoff switch and a cut switch are provided on a front side of a steering wheel.

FIG. 10 is a view showing an arrangement of shift positions of a first shift lever provided on a floor or an instrument panel and mechanically switching a shift range.

FIG. 11 is a diagram showing an arrangement of shift positions of another first shift lever provided on a floor or an instrument panel and mechanically switching a shift range.

FIG. 12 is a schematic diagram showing an example in which a cutoff switch and a cut switch are separately arranged on a front side and a rear side of a steering wheel.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine 2 Automatic transmission 4 Engine electronic control unit 6 Electronic throttle valve 10 Automatic transmission electronic control unit 61 Second shift lever 62 Cut-off switch 63 Cut switch 66 First shift lever

Claims (3)

[Claims] 1. A control device for a vehicle having an automatic transmission connected to a driving power source for driving, wherein an automatic transmission capable of setting a low-speed-side gear ratio at which an engine brake works by an electric control is provided. Fail-downshift detecting means for detecting that a shift from a high-speed gear ratio to a low-speed gear ratio at which a brake is effective has occurred; and the driving power source for traveling when the fail-downshift detecting means has detected the gearshift. A control device for a vehicle with an automatic transmission, comprising: a braking force reducing unit configured to reduce a braking force of the vehicle. 2. The throttle opening control means wherein the driving power source for driving comprises an internal combustion engine having an electrically controllable throttle valve, and the braking force reducing means increases the opening of the throttle valve. The control device for a vehicle with an automatic transmission according to claim 1, further comprising: 3. The fuel control system according to claim 1, wherein the driving power source for driving comprises an internal combustion engine capable of electrically controlling the supply and cutoff of the fuel, and the braking force reducing means stops the cutoff of the fuel and supplies the fuel. The control device for a vehicle with an automatic transmission according to claim 1 or 2, further comprising means.