JPH035248A - Interlocking control device for internal combustion engine and transmission - Google Patents

Abstract

PURPOSE:To always control optimum engine power characteristic and transmission according to a running condition by controlling to interlock one means with the other according to the condition of the other means, either a valve timing changeover means or a deciding means for transmitting characteristic of a transmission. CONSTITUTION:A solenoid valve 23 controlling operation of a changeover mechanism is provided to changeover at least one side valve timing, either intake valves or exhaust valves. A solenoid valve (not shown in the figure) controlling selection of the shift step of the automatic transmission 19 connected to the output shaft of the engine 1 according to a speed change signal output based on a speed change map is provided. These solenoid valves are controlled with an ECU 5 according to a running condition, but in the ECU 5, a first means to decide transmitting characteristic of the transmission and a second means to control the changeover condition of the valve timing changeover mechanism are provided, and according to the condition of either the first means or the second means, the one means is controlled to interlock with the other.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an interlock control device for an internal combustion engine and a transmission, and more particularly to an internal combustion engine equipped with a valve operating mechanism capable of switching the valve operating state of an intake valve or an exhaust valve. The present invention relates to an interlocking control device for a vehicle equipped with the following.

(Prior Art and Problems to be Solved by the Invention) In vehicles equipped with an automatic transmission (AT), it is common practice to control the transmission characteristics of the automatic transmission to be changed by selecting driving conditions. For example, it has been conventional practice to prepare required patterns such as a normal pattern and a sports pattern as shift patterns for a transmission, and to use these patterns accordingly. In an internal combustion engine equipped with a motor, the output can be varied by making the boost pressure of the supercharger variable, and such output control is also known.

However, the above-mentioned control is basically performed independently, and when it is performed without any correlation with each other, it is difficult to always ensure and maintain appropriate engine output control and gear shift control in response to the driving conditions. I can't wait. That is, regarding the change in the speed change characteristics of the automatic transmission, only the speed change characteristics of the automatic transmission are changed, and therefore, the output characteristics of the engine are (i
There is no change in iJ et al.

In such cases, the engine output characteristics are often not optimal for the driving conditions. Furthermore, the engine output control described in item 0;j is not a control that changes the basic characteristics of the engine specifications itself, but only changes the output by varying the boost pressure.

Some internal combustion engines include variable valve actuation mechanisms that can vary the characteristics of the intake valve or exhaust valve system. The valve operating mechanism has a low-speed switching state suitable for the low engine speed range, and automatically switches to the high-speed switching state when the engine speed reaches high speeds. Valve operation condition r
The applicant first changed the valve timing of at least one of the intake valve and exhaust valve to a low-speed valve timing (low-speed V
/T) and high-speed valve timing (high-speed V/T) suitable for high rotation range, and valve timing switching control that switches pulse and valve timing to set the optimum valve timing according to the operating condition. We have proposed (Japanese Patent Application No. 192239/1983) that such variable V/"l
'If transmission control is appropriately combined and linked to engine output control based on the mechanism, further improvement in fuel efficiency can be expected.

The present invention has been made with attention to the above points, and its purpose is to provide optimal engine output characteristic control and optimal gear shift control depending on driving conditions in controlling the internal combustion engine and transmission of a vehicle. make it possible to carry out
An object of the present invention is to provide an improved internal combustion engine and transmission interlock control device that can improve fuel efficiency.

(Means for Solving the Problems) In order to achieve the above object, the present invention changes the valve operation state of at least one of the intake valve and the exhaust valve to a low speed switching state suitable for a low rotation region and a high speed switching state suitable for a high rotation f41 region. An interlocking control device for an internal combustion engine having a valve actuation mechanism that can be switched between at least two states, including a switching state, and a transmission used in a vehicle equipped with the engine, the device determining the shifting characteristics of the transmission. a first means; a second means which is a valve actuation mechanism control means for controlling the switching state of the valve actuation mechanism; and interlock control means for controlling the other.

Note that switching the valve operating state in this specification refers to switching both or one of the valve timing and the valve lift amount.

(Example) Examples of the present invention will be described below based on the accompanying drawings.

Figure 1 is an overall configuration diagram of a control device to which the present invention is applied. Figure 11 shows an IC: in-line four-cylinder engine in which each cylinder is provided with a pair of intake valves and an exhaust valve. It is.

A throttle body 3 is provided in the middle of an intake pipe 2 of an engine 1, and a throttle valve 3' is disposed inside the throttle body 3. Throttle valve 3' has throttle valve opening (Oru)
A sensor 4 is connected to the throttle valve 3', and outputs an electric signal corresponding to the opening degree of the throttle valve 3' and supplies it to an electronic control unit (hereinafter referred to as rEcUJ) 5.

The fuel injection valve 6 is connected to the engine ■ and the slot #r3'
The injector is provided for each cylinder on the first flow side of the intake valve (not shown) of the intake pipe 2, and each injector is connected to a fuel pump (not shown). , cU5, and the valve opening time for fuel injection is controlled by signals from the ECU 3.

A spark plug 22 provided for each cylinder of the engine I is connected to the ECU 3 via a drive circuit 2I, and the CCU
3 controls the ignition timing □ig of the spark plug 22.

Further, an electromagnetic valve 23 for performing valve timing switching control, which will be described later, is connected to the output side of the ECU 3, and the opening/closing operation of the electromagnetic valve 23 is controlled by the ECU 3.

On the other hand, an intake pipe absolute pressure (Pa^) sensor 8 is provided 1α downstream of the throttle valve r3' via a pipe 7, and the absolute pressure signal converted into an electrical signal by this absolute pressure sensor 8 is sent to the flit is supplied to the ECU 3. In addition, an intake temperature (T^) sensor 9 is installed downstream of it.
It detects the intake air temperature 1゛^, outputs the corresponding W11 signal, and supplies it to the ECU 3.

Engine water temperature installed in the main body of engine l (1'w)
The sensor 10 consists of a thermistor, etc., and detects engine water if!
! (Cooling water temperature) 'I'w is detected and a corresponding temperature signal is output and supplied to EC:U5. Engine speed (Ne
) A sensor 11 and a cylinder discrimination (CYL) sensor 12 are installed around the camshaft or crankshaft of the engine l. Engine speed sensor! outputs a pulse (hereinafter referred to as "roc signal pulse J") at a predetermined crank angle position every 180 degree rotation of the crankshaft of the engine L, and the air p'Ij discrimination sensor 12 outputs a pulse at a predetermined crank angle position of the crankshaft of the engine L. It outputs signal pulses at crank angle positions, and each of these signal pulses is supplied to the ECU 3.

The three-way catalyst I4 is arranged in the exhaust pipe 13 of the engine 1, and purifies components such as LfC, Go, and NOx in the exhaust gas. 02 sensor 15 as a gas concentration detector
is the three-way catalyst in exhaust pipe 13! 4, the sensor detects the oxygen concentration in the exhaust gas, outputs a signal according to the detected value, and supplies the signal to the ECU 3.

Further, an automatic transmission [9, which will be described later], is connected to the output shaft of the engine 1.

As is known, the control of the automatic transmission 19 can be performed by means of an ``A11 pressure control device that controls the clutch section of the automatic transmission 19'' and an electromagnetic valve that operates the transmission hydraulic control device. : U5 outputs a shift signal, that is, a shift 1 signal, to the operating electromagnetic valve C as a control signal based on a shift map determined by the engine load and vehicle speed or engine rotational speed as described later, and adjusts the transmission oil pressure. A gear position (shift position) is selected by the control device driving the automatic transmission 19 according to the operation of the solenoid valve.The driving force of the engine 1 is transmitted through the output shaft of the automatic transmission 19. and is transmitted to the drive wheels (not shown) of the vehicle.

The ECU 3 further includes a vehicle speed sensor 16, a gear position sensor 17 that detects the shift position of the automatic transmission, and an oil pressure sensor 18 that detects the oil pressure in the oil supply path (48 in FIG. 2(b)) of the engine I, which will be described later. The detection signals of these sensors are supplied to the ECU 3.

ECtJ5 shapes input signal waveforms from various sensors,
Input circuit 5a that has a mechanism such as correcting the voltage level to a predetermined level and converting an analog signal value to a digital signal value.
, central processing circuit (hereinafter referred to as rcPU4) 5b, C
It is composed of a storage means 5c for storing various calculation programs and calculation results executed by the PU 5b, the fuel injection valve 6, a drive circuit 21, an output circuit 5d for supplying a drive signal to the electromagnetic valve 23, and the like.

Based on the various engine parameter signals mentioned above, the CPU 5b determines various engine operating states such as a feedback control operating range and an open loop control operating range depending on the oxygen concentration in the exhaust gas, and also determines the following depending on the engine operating state: Based on formula (1), 0:I 1' Fuel injection time TOL of the fuel injection valve 6 synchronized with the DC signal pulse
Compute IT.

"I"0UT=T i XKI+ 2-(1) 12,
Ti is the basic fuel t1ffi, specifically the engine speed N
It is the basic fuel injection time determined according to e and the intake pipe absolute pressure Pa^, and the "I" i map for determining this I' i 11α includes the low-speed valve timing ('riL map) and For high-speed valve timing ("I
Two maps "in map" are stored in the storage means 5c.

K1 and K2 are respectively a correction coefficient and a correction variable calculated according to various engine parameter signals, and are used to optimize engine characteristics such as fuel consumption characteristics and engine acceleration characteristics according to engine operating conditions. It is determined to be a predetermined value.

The CPU 5b further determines the ignition timing O1g according to the engine speed Ne and the intake pipe absolute pressure PB^. The θig map for determining the ignition timing is 1); similar to the i map in 1), there are two maps: one for low-speed valve timing (θigL map) and one for high-speed valve timing (□igu map).
Two maps are similarly stored in the storage means 5c.

C: PU5b is further processed by the method shown in FIG. 4, which will be described later.
The opening/closing control of the 'rr1 magnetic valve 23 is performed by outputting a valve timing switching instruction signal.

The CPU 5b controls the fuel injection valve 6, the drive circuit 21, and the solenoid valve 2 based on the results calculated and determined as described above.
3 is outputted via the output circuit 5d.

Furthermore, in this embodiment, the CPU 5b also receives the value of the parameter signal supplied from the throttle valve opening (OTll) sensor 4 as an engine load parameter, and the vehicle speed sensor 1.
The shift stage is determined based on the value of the parameter signal supplied from 6, and the automatic transmission 19 is controlled.

Furthermore, in this example, the transmission used is an automatic transmission,
In addition, valve timing switching is performed in two ways: low-speed valve timing suitable for low rotational speed ranges and high-speed valve timing suitable for high rotational speed ranges, but regarding switching of shift modes in combination with engine output control using such valve timing, a comparison is made. The so-called economy mode (Figure 5 (Δ)) is set to shift at a relatively low vehicle speed, and the so-called power mode is set to shift at a relatively high vehicle speed (Figure 5 (B)). ).

The economy mode is a mode that emphasizes fuel efficiency, and the power mode is a mode that emphasizes power performance, and the switching means for determining the shift characteristics of the automatic transmission 19 that emphasize fuel efficiency and power performance is a shift lever. Specifically, the shift range is changed by selecting, for example, a D range and an S (sport) range, which have different shift characteristics. As for the switching means, a switch may be used instead of a shift lever. For example, economy mode and power mode may be switched by switching the switch in the D range.

The shift pattern is stored in the storage means 5C, and the combination with valve timing control is such that the above-mentioned fuel efficiency-oriented pattern is linked to switching of the shift mode in an operating state where the valve timing is maintained at the above-mentioned low-speed valve timing. In addition, in the case of a pattern emphasizing power performance, switching between low-speed valve timing and high-speed valve timing is combined with an operation state in which a collation is performed. That is, in the case of an A1 degree vehicle, for example, based on the range determined by the shift lever, the valve timing can be fixed at low speed valve timing in D range, and can be switched between low speed valve timing and high speed valve timing in S range. .

In this example, a configuration is adopted in which switching between high-speed valve timing and low-speed valve timing is performed by selecting a rocker arm and a cam as described below.

FIG. 2 shows an intake valve side valve train 30 that drives the intake valves 40 of each cylinder of the engine I, but a valve train with basically the same configuration as this is also provided on the exhaust valve side. . This valve train ji130 has a camshaft 3 which is rotationally driven at a speed ratio of 1/2 from the crankshaft (not shown) of the engine
1, a high speed cam 34 and a low speed cam 32, 33 provided on the camshaft 31 corresponding to each cylinder, respectively,
A rocker shaft 35 fixedly arranged parallel to the camshaft 31, a first driving rocker arm 36, a second driving rocker arm 37, and a free rocker arm 38 that are pivotally supported on the rocker shaft 35 in correspondence with each cylinder, and each cylinder. A connection switching mechanism 39 is provided between each rocker arm 36, 37, and 38 corresponding to the above.

In FIG. 2(b), the connection switching mechanism 39 includes a first switching bin 41 that can connect the first driving rocker arm 36 and the free rocker arm 38, and a first switching bin 41 that can connect the free rocker arm 38 and the second driving rocker arm 37. 2 switching bin 4
2, a regulation bin 43 that regulates the movement of the first and second switching bins 41 and 42, and a return spring 44 that urges each of the bins 41 to 43 toward the disconnection side.

The first drive rocker arm 36 includes a free rocker arm 38.
A first guide hole 45 with a bottom and open to the side is bored parallel to the rocker shaft 35, and the first switching bin 41 is slidably fitted into the first guide hole 45, and the first A hydraulic chamber 46 is defined between one end of the switching bin 4I and the closed end of the first guide hole 45.
A passage 47 communicating with the hydraulic chamber 46 is bored in the rocker shaft 35, and an oil supply passage 48 is provided in the rocker shaft 35. 46 is always connected.

A guide hole 49 corresponding to the first guide hole 45 is bored in the free rocker arm 38 in parallel with the rocker shaft 35 and extends between both sides, and one end is brought into contact with the bottom end of the first switching bin 41. The second switching bin 42 is in the guide hole 49
is slidably fitted to.

The second drive rocker arm 37 has a 0;1 guide hole 49.
A second guide hole 50 with a bottom corresponding to the second switch arm 38 is opened in parallel with the rocker shaft 35, and a disc-shaped regulation bin 43 that abuts the end of the second switching bin 42 is inserted into the second switching bin 42. It is slidably fitted into the second guide hole 50. Moreover, a guide tube 51 is provided at the closed end of the second guide hole 50.
A shaft portion 52 that is slidably fitted into the guide tube 51 is coaxially and integrally protruded with the regulation pin 42 . In addition, the return spring 44 is connected to the guide tube 51 and the regulation bin 43.
This return spring 44 causes each bottle 4 to
1, 42, and 43 are pushed toward the hydraulic chamber 46 side.

In this connection switching mechanism 39, as the hydraulic pressure in the hydraulic chamber 46 increases, the first switching bin 41 fits into the guide hole 49, and the second switching bin 42 fits into the second guide hole 50, so that each Rocker arms 36, 38, 37 are connected. Furthermore, when the oil pressure in the hydraulic chamber 46 becomes low, the spring force of the return spring 44 causes the contact surface of the first switching bin 41 with the second switching bin 42 to return to the position corresponding to between the first drive rocker arm 36 and the free rocker arm 38. Since the contact surface of the second switching bin 42 with the regulation bin 43 returns to the position corresponding to between the free rocker arm 38 and the second driving rocker arm 37, the connection state of each rocker arm 36, 38, 37 is released.

The oil supply path 48 in the lock shaft 35 is connected to the switching valve 24.
The hydraulic pressure in the oil supply passage 48 and, therefore, the hydraulic pressure in the hydraulic chamber 46 of the connection switching mechanism 39 is switched between high and low levels by the switching operation of the switching valve 24. This switching valve 24 is connected to the electromagnetic valve 23, and the switching operation of the switching valve 24 is controlled by the ECU 3 via the electromagnetic valve 23.

Intake side valve operating device 3 of engine 1 configured as described above
0 operates as follows. Incidentally, the exhaust side valve train operates in the same manner.

When the ECU 3 outputs a valve opening command signal to the solenoid valve 23, the solenoid valve 23 is opened, the switching valve 24 is opened, and the oil pressure in the oil supply passage 48 is increased. As a result, the connection switching mechanism 39 operates and each rocker arm 36, 38.3
7 is in a connected state, each rocker arm 36°38.37 is operated integrally by the high-speed cam 34, and the pair of intake valves 40 are opened and closed at high-speed valve timing with a relatively large valve opening period and lift amount. .

On the other hand, when a valve closing command signal is output from the ECU 3 to the solenoid valve 23, the solenoid valve 23 and the switching valve 24 are operated to close.
, the oil pressure in the oil supply passage 48 decreases. As a result, the connection switching mechanism 39 operates in the opposite manner to the above, and each rocker arm 36, 3
The connection state of 8.37 is released, and the low speed cam 32.33
As a result, the corresponding rocker arms 36 and 37 are actuated, and the pair of intake valves 40 are actuated at low valve timing with a relatively small valve opening period and lift amount.

FIG. 3 is a diagram showing the characteristics of engine output by valve timing control according to the present invention, and shows engine rotation speed Ne and engine output (P
This shows the relationship with S).

Engine speed NFL is determined by low-speed valve timing (V/T
) is the engine speed at which peak power is obtained, and engine speed NPI+ is the engine speed at which peak power is obtained at high speed valve timing (V/T
) is the engine rotation speed at which peak power is obtained. In the figure, in the case of the economy mode or the D range, for example, where fuel efficiency is emphasized as described above, the valve timing is fixed and maintained at a low speed valve timing that exhibits the output characteristics shown by the solid line, as will be described later. In other words, a low-speed valve timing holding state is established in which switching from low-speed valve timing to high-speed valve timing is prohibited. In addition, in the case of power mode or S range that emphasizes power performance, low speed valve timing and high speed valve timing switching control,
That is, the engine is controlled to a switching permissible state that allows switching between low-speed valve timing and high-speed valve timing, and in this case, the engine output characteristics are changed depending on the operating condition between the high-speed valve exhibiting the output characteristic shown in the solid line and the output characteristic shown in the broken line. It will be switched to the timing one.

As shown in the figure, the power peak rotation speed changes depending on the low-speed valve timing and high-speed valve timing.

This interlocking control utilizes such low-speed valve timing and high-speed valve timing output characteristics of the variable valve timing engine.

The basics of the control are, as an engine output and transmission characteristic control device, a selection means for selecting driving conditions, a changing means for changing the engine output according to the selection, and a vehicle equipped with an automatic transmission (AT) as in this embodiment. Regarding this, a configuration having a changing means for changing the speed change characteristics is adopted.

That is, in the case of an AT vehicle, interlocking control involves engine output control based on engine output characteristics that occur at each valve timing and valve lift amount of a variable V/T engine that makes valve timing and valve lift variable; This system performs speed change control of the automatic transmission in combination with the output control, and by selecting the driving conditions, it is possible to obtain the optimal engine output characteristics and the optimal transmission characteristics for the driving conditions, and to increase the engine output. The purpose is to reduce the fuel consumption rate under driving conditions that do not require fuel consumption, and to obtain optimal fuel efficiency under any driving conditions.

In order to improve fuel efficiency by providing optimal engine output characteristics and optimal shift characteristics (AT vehicles) depending on driving conditions, the output characteristics of low-speed valve timing and high-speed valve timing shown in Figure 3 are used to change the shift mode. In conjunction with the switching, a combination of fixed low-speed valve timing control and switching control between low-speed valve timing and high-speed valve timing is performed, thereby achieving the optimum speed change characteristics and engine output characteristics for the driving conditions. This provides fuel efficiency.

The following refers to vehicles with automatic transmissions, i.e. automatic vehicles (AT).
This case will be explained in more detail with reference to FIGS. 4 and 5.

FIG. 4 shows a program for controlling valve timing switching using the above-described configuration, including interlocking control of low-speed valve timing fixation and low-speed valve timing and high-speed valve timing switching in conjunction with shift mode switching. This is a flowchart.

This program example shows an example in which the shift characteristics are changed between the automatic L (1) range and the S range. In addition, this program is 'rp
This is executed in synchronization with each c signal pulse generation.

First, in step 31, it is determined whether or not No. 1a is normally inputted to the ECU 3 from various sensors, or whether an abnormality has already occurred in another control system, that is, whether failsafe should be performed.

Specifically, the intake pipe absolute pressure (PB^) sensor 8, cylinder discrimination (CYL) sensor 12, engine speed (TDC:)
Sensor 11, engine water temperature sensor 10, vehicle speed sensor 16
J'% of output from normal, ignition timing control signal output and fuel injection control output abnormal, valve timing control solenoid valve 2
3, a normal oil pressure change in the outlet boat (not shown) located in the switching valve 24 and communicating with the oil supply path 48 in response to the opening and closing of the solenoid valve 23 for valve timing control. The oil pressure switch in the sensor 18 detects an abnormality that cannot be confirmed even after a predetermined period of time has elapsed, and determines that the engine is in a fail-safe operating state. In addition,
When there is an abnormality in one of the cylinder discrimination (CYL) sensor and the 'I' DC sensor, the output of the one is substituted with the output of the capacity.

If the answer to step S1 is affirmative (Yes), that is, fail-safe should be performed, the process proceeds to step S33, which will be described later, and is negative (
If NO), the process proceeds to step S2 and subsequent steps.

Steps S2 to SIO are steps for determining whether or not the engine output can be reduced. One of these steps is economy mode.

When in the D range, the low-speed valve timing is fixed for better fuel efficiency, and the S
It includes a step of determining the mode of the transmission so as to perform switching control between low-speed valve timing and high-speed valve timing when in range.

First, in step S2, it is determined whether the engine is starting or not based on the engine rotational speed Ne and the like. Step S3 is a step for determining whether or not the remaining time 1', I]tsy of the delay timer has become O. It is necessary to set tsy to a predetermined time (for example, 5 seconds) while starting tsy (step S4), and after starting Started the timekeeping operation.

In step S5, the engine water temperature Tw is set to a predetermined set temperature Tw.
S6 is a step of determining whether the vehicle speed V is lower than 1 (e.g., 60° C.), that is, whether warm-up has been completed.
5 km), step S7 is the step of determining whether the transmission mode is the above-mentioned transmission mode, that is, the economy mode;
Step S8 is a step to determine whether the engine equipped with the engine 1 is in the manual transmission (MT). S9 is a step in which the shift lever is in the parking (P) range or the parking (P) range in the case of an automatic transmission vehicle (AT). Neutral (N)
Step to determine whether the microwave is on or not, SIO
is a step for determining whether Ne is less than or equal to the lower limit Ne+.
es)) and the set time tsT elapsed 01j of the post-start delay timer (the answer to step S3 is negative (No)), during warming up, that is, at low water temperature (the answer to step S5 is affirmative (Yes)),
While stopping or slowing down (the answer to step S6 is 1# (Yes))
), economy mode, and D range, that is, when emphasis is placed on fuel efficiency (Fig. 5 (A)) (the answer to step S7 is affirmative (Yes)), and when the P and N ranges are selected (the answer to step S9 is If the answer is negative (Yes) and Ne (Ne+) (the answer to step SIO is negative (No)), the solenoid valve 23 is closed to maintain the valve timing at a low speed valve timing, as will be described later.

Therefore, for example, the engine water @1゛W is at a predetermined temperature Tw+
At lower operating conditions, the valve timing will be fixed at the slow valve timing, and the fifth
As shown in Figure (A), in the economy mode where the shift pattern emphasizes fuel efficiency, the valve timing is fixed to the low-speed valve timing of the engine output characteristics as shown in Figure 3 in conjunction with the change of the shift mode. It turns out.

That is, if the answer to step S7 is affirmative (Yes), low-speed valve timing fixed control is executed and maintained through the processes of steps 331 and 830 (described later) (if the answer to step S7 is negative (No), l' (Yes)

An example of the shift map shown in FIG. 5 shows an example in which the shift characteristics are determined by the throttle valve opening 0TII and the vehicle speed V, as shown. In the maps shown in Figure 5 (A) and (B) above, between the economy mode and the power mode, the shift pattern of the latter power mode in Figure 5 (B) is different from that of the former, as shown in the figure. The points have been shifted so that automatic gear shifting occurs at high vehicle speeds. That is, the vehicle speed line is shifted to the high vehicle speed line.

In the case of the above-mentioned economy mode, the upshift is performed as quickly as possible, and the fuel efficiency can be improved compared to the power mode.

On the other hand, in the case of power mode, the focus is on power performance,
The purpose is to allow the vehicle to be towed at as low a speed as possible, that is, to allow the driver to travel at 1 speed if he or she wishes to travel fast. Therefore, by linking these with valve timing control, if the economy mode was adopted (selected), the fuel consumption would be tJ, visual.
As mentioned above, the valve timing is fixed at low speed. That is, if high-speed valve timing is used, this will consume a lot of fuel and reduce fuel efficiency, so switching to this is prohibited and the low-speed valve timing is fixed.

However, when changing the shifting characteristics to power mode,
In other words, when the driver requests acceleration (the answers to steps S7 and 9 are negative), the low-speed valve timing and high-speed valve timing can be switched in order to respond to this request, as will be described later. , that is, switching is allowed.

As described above, in conjunction with switching the shift mode,
Utilizing the output characteristics of low-speed valve timing and high-speed valve timing with variable valve timing, the control can be switched between two modes: fixed low-speed valve timing control and switching control for each valve timing, depending on driving conditions, and in combination with engine output control. , it is possible to obtain the optimum transmission characteristics and engine output characteristics for the driving conditions, and to obtain the optimum fuel efficiency.

In the example shown in FIG. 5 above, the speed change is performed based on the speed change characteristics determined by the throttle valve opening as the engine load parameter and the vehicle speed as one of the other parameters. As an example, the engine speed may be applied, and in this case, the shift characteristics may be similar to the above example, and the gears may be shifted at relatively low and high engine speeds for each shift pattern.

Returning to FIG. 4, the answer in step S7 is negative (No.
), that is, it is determined that the power mode is S range, and step S8. In the case where the process proceeds to the step SIO via S9, if it is determined in the step SIO that Ne≧Ne+ holds true, TiL is determined in the step Sll.
Search map and 'rin map, current Ne,
The Ti value (hereinafter referred to as 1'iL) of the TiL map and the Tj value (hereinafter referred to as 'rin) of the ``I'io map'' corresponding to PB^ are determined, and then in step S12, the Δ'l'' car and M The 'I'VT corresponding to Ne is read from the Tvt table set according to the 'r car, and this 'I'VT is read out in step S13.
"Compare vr and 'J'our of the previous loop, and
It is determined whether IJT≧TVT holds true or not, that is, whether the air-fuel mixture is in a high load state to enrich it. The answer is negative (N
o), that is, when 'l''0IJT<l' VT holds, the process proceeds to step S14 and Ne is set to the upper limit value N in mj.
It is determined whether or not it is equal to or greater than e2. When the answer to step S14 is negative (No), that is, Ne (Ne2 holds true),
Proceeding to step 815, the I obtained in step Sll is
'Compare it and Tin. As a result, TiL)Ti
When ++ is established, it is determined whether or not the timer value t and vropp of the delay timer set in step 816 (described later) are zero (step 517), and the answer is affirmative (Y).
es), a valve closing command for the solenoid valve 23 is issued in step SI8,
In other words, a command to switch to low-speed pub timing is issued. Also, the step S l3. S l 4. At each step of S l 5, TOUT≧TVT, Ne≧Ne2, 'r
When it≦I'in, the timer value of the solenoid valve opening delay timer is set to LVTOFF.
(for example, 3 seconds) and start (step $
16) In step S19, a command to open the solenoid valve 23, that is, a command to switch to high-speed pub timing is issued.

When the valve closing command is issued in step S18, it is determined in step S20 whether the oil pressure switch in the oil pressure sensor 18 has been turned on, that is, whether the oil pressure in the oil supply path 48 has become low pressure. If the answer is affirmative (Yes), that is, the oil pressure switch is turned on, it is determined in step S22 whether the remaining time tLVT of the low-speed valve timing switching delay timer has become O. When the answer to step S22 is affirmative (Yes), that is, tLv−r=o,
In step S24, the remaining time of the high-speed valve timing switching delay timer is set to a set time (for example, 0.1 seconds).
Then, in step S26, a process is performed to select the "I'it map" and the ignition timing map for low-speed valve timing (OigL map) as the Ti map and ignition timing map used in the fuel injection control routine, respectively. In step S28, the rev limiter value NIIFC is set to l/JNnpc+ for low-speed valve timing.

On the other hand, when the valve opening command is issued in step S19, it is determined in step S21 whether the oil pressure switch in the oil pressure sensor 18 has been turned off, that is, whether the oil pressure in the oil supply path 48 has become high pressure. If the answer is affirmative (Yes), that is, the oil pressure switch is turned off, the remaining time tllV of the high-speed valve timing switching delay timer is determined in step S23.
It is determined whether T has become 0 or not. If the answer to step S23 is affirmative (Yes), that is, t,++vy=0, then in step S25 the remaining time tLVT of the low-speed valve timing switching delay timer is set to a set time (for example, 0
．． 2 seconds), and then, in step 327, a process is performed to select the Tin map and the ignition timing map for high-speed valve timing (Oigu map) as the 1゛i map and ignition timing map used in the fuel injection control routine, respectively. Then, in the subsequent step S29, processing is performed to set NIIFC to tiaNIIFc2 for high-speed valve timing.

By the way, the above-mentioned double switching delay timer t, IIVT
.

The setting time of LVT is the response delay time until the solenoid valve 23 is opened and closed, the switching valve 24 is switched, the oil pressure in the oil supply passage 48 is changed, and the switching operation of the connection switching mechanism 39 for all cylinders is completed. It is set accordingly, and solenoid valve 2
3, the program goes from S20 to S23 until the oil pressure switch in the oil pressure sensor 18 is turned on.
It proceeds in the order of S25 → S27 → S29, and even after turning on, it proceeds in the order of S20 → S22 → S27 → S29 until the connection switching mechanism 39 of all cylinders is switched to the low speed valve timing side, and the solenoid valve 23 and switching valve 24 Even if the switching valve 24 does not switch to the closing side even if a valve closing command is issued due to a failure or the like, and the oil pressure switch in the oil pressure sensor 18 does not turn on for a long time, the steps S20→S23→S25→S27→
Proceeding to step S29, the connection switching mechanism 39 for all cylinders is finally installed.
As long as the fuel injection control is not switched to the low valve timing side, the fuel injection control is maintained compatible with the high valve timing. When the solenoid valve 23 is switched from closed to open, the fuel injection control is adapted to the low-speed valve timing in the same manner as described above, unless the connection switching mechanism 39 for all cylinders is switched to the high-speed valve timing side. maintained.

On the other hand, if the answer to step S2 is affirmative (Yes), or if the answer to step S3 is negative (No), or if the answer to step S5. If the answer to S6 is affirmative (Yes), that is, during startup, before the set time has elapsed after startup, during warm-up, that is, when the water temperature is low, or when the vehicle is stopped or driving slowly, the process proceeds to step S30 and the solenoid valve 23 is closed. Issue a command and proceed from steps S30 to S24→
The process proceeds in the order of S26→S28.

In an internal combustion engine that can be switched between low-speed valve timing and high-speed valve timing, when the engine water temperature is low and therefore the viscosity of the engine oil is high, the friction in various parts of the engine such as bearings is high, so the low speed range The engine is controlled to be fixed at a low-speed valve timing suitable for the engine, thereby protecting the engine.

As already mentioned, if the determination in step $7 is the economy mode and the D range, and if the determination in step S9 of 0:j is in the N or P range, the process advances to step S31 and the Tin value is set in the previous loop. It is determined whether a map is selected or not, and in the step SIO, Ne(
When Ne+ is established, the process also proceeds to step S31. When the answer to step S31 is affirmative (Yes), that is, when the previous loop T'in map has been selected, the timer value Lv'ropp of the n;j solenoid valve opening delay timer is set to zero (step 532). ), the process proceeds to step SI8, and when the answer to step S31 is negative (NO), that is, nij times 1'i.

When the map is not in use, in other words, when the connection switching mechanism 39 for all cylinders is not switched to the high-speed valve timing side, 530-4S24 →
The process proceeds in the order of S26→328, and fuel injection control is performed in accordance with the low-speed valve timing, regardless of the oil pressure switch in the oil pressure sensor 18. This is a measure to be taken when the oil pressure switch in the oil pressure sensor 18 is permanently turned off due to disconnection or the like.

By the way, the above-mentioned Nnpct is set higher than Ne2, and normally Ne increases to NIIFCI (0; 1).
Since the valve timing is switched to high-speed valve timing and the N+ζFC level is switched to N11FC2, no fuel cut is performed at NIIPCI. On the other hand, in the operating state portion where the process proceeds from steps 82 to S9 to step S30, the low valve timing is maintained even if Ne turns around Ne2 by J1 due to dry cooking, etc., so N It
Fuel cut will be carried out at FCI. Also, even when switching from low-speed valve timing to high-speed valve timing, tn
Fuel cut is performed at Nopc+ until vy becomes O, that is, until the coupling mechanism 39 actually switches to the high-speed valve timing side.

Also, l? The answer to step SL of jf is 19 (Yes)
That is, when in fail-safe mode, a valve closing command is issued to the electromagnetic valve 23 (step 533), fail-safe processing is executed (step 834), the process proceeds to step 828, and the present control program is terminated. Here, in the fail-safe process, it is also possible to fix +l1lJ fil to the same low speed valve timing as when the engine water temperature is low as described above.

Note that in the above explanation, the switching of the shift mode, which is the negative element of interlocking if/J#, and the control of the valve timing, which is the negative element, are controlled in accordance with the former, but the latter is controlled according to the former. This is also possible in reverse. In other words, in the above example, under the conditions where the valve timing is fixed at low speed (low water temperature, valve timing fail-safe), even if the power mode is selected, from the viewpoint of fuel efficiency mentioned above, , it may be possible to perform interlocking control to forcibly set this to the economy mode, that is, to automatically switch to the economy mode. The interlock control according to the present invention can also be applied in such a manner.

Next, an embodiment of the pond of the present invention will be described.

In the above embodiment, the case of interlocking it, II n of an AT vehicle has been described, but the present invention can be similarly applied to a manual transmission vehicle (MT) using a manual transmission as a transmission.

In the case of a manual transmission vehicle, a selection switch (SEL SW) is used as a means to vary engine output depending on driving conditions.
) will be established. The driving condition selection switch (SEL SW)
) is a switch that can be manually operated by the driver as a mode switch, and the switch (SEL SW
) switching states (switching positions) are, for example, in the case of the engine ttR car with the variable valve timing machine tR in the above embodiment, a mode in which the low-speed valve timing is fixed, and a mode in which the low-speed valve timing and high-speed valve timing can be switched. According to the two control modes, the number can be set to two,
These control modes are switched in conjunction with the driving condition selection switch (S[ELSW).

In other words, the selection switch (SEL SW) allows the driver to fix the valve timing to low-speed valve timing, or to switch between low and high valve timing. It is used to select whether to If the driver selects one of the above, for example, if the driving condition selection switch (SEL SW) is set to the fixed low-speed valve timing mode, then in such a state, the mode corresponds to the economy mode that emphasizes fuel efficiency. If the mode is set to the side where low-speed valve timing and high-speed valve timing can be switched, this corresponds to a power mode that emphasizes power performance.

The modes that can be selected are not limited to economy and power, but also economy (e.g.
The mode may be set to 3s or higher, such as (emphasis on fuel efficiency), normal (an intermediate mode between emphasis on fuel economy and power performance), and power (emphasis on power performance).

In this embodiment, the driving condition selection switch (SE
It also has an economy mode and a power mode as selectable modes for varying the engine output, and by switching the mode switch (SE, L SW) by the driver,
When the driver selects the economy mode, the low speed valve timing is fixed, and when the driver selects the power mode, the low speed valve timing and high speed valve timing are controlled. That is, as mentioned above, the output characteristics of low-speed valve timing and high-speed valve timing (Fig. 3) are used, and depending on the driving conditions, the low-speed valve timing can be fixed (economy mode side), the low-speed valve timing and high-speed valve timing can be changed. Switch the switching system 91 (power mode side).

The interlocking control in the case of M 7F small focuses on the following points.

In other words, when the selection switch (SEL SW) is switched to the economy mode side by the driver, the engine output characteristics at the valve timing are fixed at low speed valve timing. is shown by a solid line in FIG. 3, and in this characteristic, the power quickly reaches a plateau as the engine speed Ne increases. Therefore, when the driver performs a manual shift, the driver performs the shift operation earlier.

When the selection switch (SEL SW) is selected to switch to the power mode side, that is, when the valve timing is in a state where low and high switching is allowed, the engine output characteristics at that time are as described above. Solid line in the figure (low speed V/”
I''), as shown by the broken line (high-speed V/T), it is possible to operate the engine to a higher rotation speed (even when shifting, the driver must already shift). (I think the engine speed at that point will also change).

In other words, the driver presses the driving condition selection switch (SEL).
Depending on which switching state the SW) is in, the criteria for whether or not the driver will be able to shift early when changing gears will change. Most people shift gears manually, but when it comes to valve timing, there is a switch (SEL).
(SW), the mode is fixed (low speed V/1") or switchable 6 (low speed V/T, high speed V/T), so the driver feels he has to change the gear himself. The recognition point also changes at the same time, and as a result, the conditions for manual shifting also change.)

To explain more specifically below, the interlocking control device for an MT vehicle has the automatic transmission 19 changed to a manual transmission in FIG. 1, and the driving condition selection switch ( The switching state signal from SELSW is supplied, and the IEcU 5 can detect and monitor the switching state.

Monitoring of the selection switch (SEL SW) and determination of the switching state can be performed by replacing the determination step S7 in the program shown in FIG. 4 with one for determining the switching state of the selection switch (SEL SW). Depending on the result of the determination, the program can be configured to proceed to step 331 and below (thus fixing low speed V/i'), or proceed to step SIO via step S8 (low speed V/T, high speed V/T control). can.

In the above, when each switching state is selected, the interlock control device allows the driver to adopt the following maneuvering method.

Now, the driver wants to drive quickly by accelerating, etc., and selects the driving condition selection switch (SEL SW) to select low speed V/T and high speed V7.
Assuming that the switching state is on the power mode side of T control or Troll, in such a state, the engine speed Ne at which the driver feels that the driver should shift is the same as the engine output characteristic shown by the solid line in Figure 3 (low speed Compared to the case where the engine is fixed to V / "I'), the engine speed will be higher. In this case, the emphasis is on power performance, and even if the driver depresses the accelerator pedal, the engine speed will no longer increase. But once you know that there is no need to change, you will upshift.
In this case, compared to the case where the output characteristics are fixed to the solid line in FIG. This allows the engine to upshift at higher rotational speeds, making it possible to pull at as high a rotational speed as possible, making it possible to drive with an emphasis on power performance.

Further, when the driver switches the driving condition selection switch (SELSW) to the economy mode side instead of the above switching state, the following occurs.

That is, the selection in this case is one that emphasizes fuel efficiency, but at the time of such selection, the low speed valve timing is fixed (processing from step 331 onwards is executed), and therefore the engine output characteristics are as shown by the solid line in FIG. 3. In this case, the beak power decreases, and the driver will shift earlier than in the above case where emphasis is placed on power performance.

In this case, the timing to shift can be easily recognized by listening to the engine speed or looking at the tachometer.

In this way, the driver learns the current driving condition from changes in the engine speed and the m-hand display on the tachometer, and the driving condition selection switch (SEL SW) is activated.
1) When the shift state is switched to the economy mode side, the driver himself/herself starts to operate the shift earlier and earlier, thereby improving fuel efficiency.

As described above, this interlock control can be applied even to MT vehicles, and by interlocking with the driving condition selection switch (SELSW), engine output characteristics optimal for the driving conditions can be obtained, and the best fuel efficiency can be obtained.

Although the example shown in FIG. 3 has been described above regarding engine output control, the invention is not limited to this.

For example, if there are three types of valve timing (low speed, medium speed, high speed V/T, etc.), in the case of a manual transmission vehicle, there will be three modes for selection.

Furthermore, multi-stage output control can be performed by combining with a supercharger (turbocharger, supercharger), variable intake (pipe switching, resonance supercharging), variable compression, and even a high-speed V/T mechanism.

In addition, by combining valve deactivation, A/l'' lean, shift indicators, etc., it is possible to perform control that further improves fuel efficiency.

(Effects of the Invention) According to the present invention, the valve operating state of at least one of the intake valve and the exhaust valve is set to at least two states: a low-speed switching state suitable for a low-speed range and a high-speed switching state suitable for a high-speed range. An interlock control device for an internal combustion engine having a switchable valve actuation mechanism and a transmission used in a vehicle equipped with the engine, the device comprising: a first means for determining a shift characteristic of the transmission; A valve actuator that controls the switching state of the valve distribution actuation mechanism (a second means which is a control means, and a second means which is a control means, and the other depending on the state of one of the vehicle dispatching means and the second means) Since the vehicle is equipped with an interlocking control means for controlling the engine output characteristics, it is possible to perform optimal engine output characteristic control and optimal gear change control depending on the driving conditions, and it is possible to improve fuel efficiency.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of a control device for a vehicle to which an interlocking control device for an internal combustion engine and an automatic transmission according to an embodiment of the present invention is applied, and FIG. 2 is a diagram showing an engine valve train and its control system. Figure 3 is a diagram showing an example of engine output characteristics by valve timing control, and Figure 4 is a diagram showing an example of engine output characteristics by valve timing control. FIG. 5 is a flowchart showing an example of a program for controlling switching of valve timing shown in FIG. 1... Internal combustion engine, 4... Throttle valve opening sensor, 5... Electronic control unit (ECU), 6
...Fuel injection valve, 11...Engine speed sensor,
16...Vehicle speed sensor, 19...Automatic transmission, 23.
...Solenoid valve, 24...Switching valve, 30...Valve train,
40...Intake valve or exhaust valve.

Claims (1)

[Claims] 1. The valve operating state of at least one of the intake valve and the exhaust valve can be switched to at least two states: a low-speed switching state suitable for a low-speed range and a high-speed switching state suitable for a high-speed range. An interlock control device for an internal combustion engine having a valve actuation mechanism and a transmission used in a vehicle equipped with the engine, the device comprising: first means for determining shift characteristics of the transmission; and switching of the valve actuation mechanism. It is characterized by having a second means which is a valve actuation mechanism control means for controlling the state, and an interlocking control means for controlling either the first means or the second means depending on the state of the other. An interlocking control device for an internal combustion engine and a transmission. 2. The internal combustion engine according to claim 1, wherein the transmission is a manual transmission, and the second means includes a switching means for selecting driving conditions that can be selectively switched by the driver. and transmission interlock control device. 3. The first means is an economy mode set to perform automatic gear shifting at a relatively low engine rotation or low vehicle speed, and a power mode set to perform automatic gear shifting at a relatively high engine rotation or high vehicle speed. 2. The interlock control device for an internal combustion engine and a transmission according to claim 1, wherein the interlock control device is configured to switch between modes. 4. The valve actuation mechanism control means, which is the second means, maintains a low-speed switching state in which switching from the low-speed switching state to the high-speed switching state is prohibited, and switches between the low-speed switching state and the high-speed switching state. 4. An interlocking control device for an internal combustion engine and a transmission according to claim 1, wherein the interlock control device controls switching between a permissible switching state and a permissible switching state.