JPH1120459A - Transmission controller of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sufficiently ensure the heating capability by correcting the change gear ratio low in the operation with an engine cooling water temperature lower than a low gear water temperature level when a high heating capability is required. SOLUTION: A CVT control unit 41 judges an operating state requiring high heating capability, and corrects the target change gear ratio of a continuously variable transmission to be low so that the operating state with an engine water temperature TW lower than a low gear water temperature level is provided when the high heating capability is required. The judgment of the operating state requiring high heating capability is performed by judging the cooling water temperature drop, outside air temperature drop, or rise of fan air quantity of a heater fan at the time of engine start. When it is judged to require the high heating capability, the change gear ratio is corrected low to promote warming by increasing the number of rotation and the heating amount of the engine, and after the engine is warmed, and the heating capability within the cabin is sufficiently ensured. Thus, the heating value of the engine is increased according to the increase in required heating capability, and a sufficient heating capability can be ensured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for a vehicle, which controls a shift ratio in accordance with a required heating capacity.

[0002]

2. Description of the Related Art Shift control of a continuously variable transmission mounted on a vehicle is controlled in accordance with operating conditions such as an accelerator opening and a vehicle speed.

[0003] A heater device for heating the interior of a vehicle is configured to blow heat radiation of engine coolant circulating through a heater core into the vehicle interior by driving a heater fan.

[0004] As an engine mounted on a vehicle, there is an engine that operates even at an air-fuel ratio larger than the stoichiometric air-fuel ratio (stoichiometric), that is, a lean air-fuel ratio (see Japanese Patent Application Laid-Open No. Sho 62-17340).

[0005]

However, in a cold region, if the operation is continued at a lean air-fuel ratio (lean burn) with a large gear ratio and a low engine speed, the amount of heat generated by the engine becomes insufficient. Therefore, there is a possibility that the heating of the passenger compartment by the heater device cannot be performed sufficiently.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a vehicle speed change control device with sufficient heating capacity.

[0007]

According to a first aspect of the present invention, there is provided a shift control device for a vehicle, comprising: a heater device for heating a vehicle interior by radiating engine cooling water; and a gear ratio of a transmission according to an operating state of the vehicle. A shift control device for a vehicle, comprising: a control unit that controls the heating device; and a determining unit that determines whether the heater device is in operation when the heating capability is higher than a predetermined value; and an engine coolant temperature detection unit that detects an engine coolant temperature. Means and a gear ratio correction means for correcting the gear ratio to be low when the engine cooling water temperature is equal to or lower than the low gear water temperature level when a high heating capacity is required.

According to a second aspect of the present invention, there is provided a shift control device for a vehicle.
In the speed ratio correction means according to the first aspect, when the cooling water temperature at the time of starting the engine is low, the low geared water temperature level is increased.

According to a third aspect of the present invention, there is provided a vehicle speed change control device.
The invention according to claim 1 or 2, further comprising an outside air temperature detecting means for detecting an outside air temperature, wherein the speed ratio correction means increases the low gear water temperature level when the outside air temperature is low.

According to a fourth aspect of the present invention, there is provided a shift control device for a vehicle.
In the invention according to any one of claims 1 to 3,
A heater fan that sends the heat of the engine cooling water into the cabin,
A fan air flow detecting means for detecting a fan air flow of the heater fan, wherein the speed ratio correcting means increases the low gear water temperature level when the fan air flow is large.

According to a fifth aspect of the present invention, there is provided a shift control device for a vehicle.
In the invention according to any one of claims 1 to 4,
The mixture supplied to the engine is controlled to a lean air-fuel ratio in a predetermined low speed range.

[0012]

According to the shift control device for a vehicle according to the present invention, the engine speed is corrected to be low when the engine cooling water temperature is lower than the low gear water temperature level when a high heating capacity is required, so that the engine speed can be reduced. As a result, the amount of heat generated by the engine is increased, the warm-up of the engine is promoted, and the heating capacity of the passenger compartment is sufficiently secured even after the engine is warmed up.

When the required heating capacity is lower than a predetermined value, the speed ratio is not corrected to a low value during operation, so that the engine speed is not increased and the fuel efficiency is improved.

According to a second aspect of the present invention, when the cooling water temperature at the time of starting the engine is low, the low-gear water temperature level is increased to increase the required heating capacity. To increase the heating capacity.

According to a third aspect of the present invention, when the outside air temperature is low, the low-gear water temperature level is increased to increase the amount of heat generated by the engine in accordance with an increase in the required heating capacity. Heating capacity can be secured.

According to a fourth aspect of the present invention, when the air flow of the heater fan is large, the low-gear water temperature level is increased when the fan airflow of the heater fan is large. Increase and secure sufficient heating capacity.

According to a fifth aspect of the present invention, when the engine cooling water temperature is equal to or lower than the low gear water temperature level when the high cooling capacity is required, the gear ratio is corrected to be low so that the lean air-fuel mixture is supplied to the engine. The operating range controlled by the fuel ratio is reduced, the calorific value of the engine is increased, the warm-up of the engine is promoted, and the heating capacity of the passenger compartment is sufficiently secured even after the warm-up of the engine.

Since the gear ratio is not corrected to a low value when the required heating capacity is lower than a predetermined value, the operating range in which the mixture supplied to the engine is controlled to the lean air-fuel ratio is expanded, and the fuel efficiency is improved.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram of a shift control device for a V-belt type continuously variable transmission.

A torque converter 52 as a starting element is interposed between the engine (not shown) and the continuously variable transmission 57. The continuously variable transmission 57 is connected to the output side of the torque converter 52 as a variable pulley. Primary pulley 56
And a secondary pulley 66 connected to the drive shaft,
These variable pulleys are connected by a V-belt 64.

The torque converter 5 as the starting element
2 is provided with a lock-up clutch 51 for connecting the input side and the output side, and has a predetermined operating state, for example, a vehicle speed VSP.
Is larger than the predetermined value Va, the lock-up clutch 51
Is concluded.

The gear ratio of the continuously variable transmission 57 and the lock-up clutch 51 are connected to the CVT control unit 4.
1 is controlled by a hydraulic control valve 43 responsive to a command from the control unit 1.

The CVT control unit 41 includes a primary pulley rotation speed sensor 46 for detecting the rotation speed Npri of the primary pulley 56 of the continuously variable transmission 57 and a secondary pulley rotation speed sensor 47 for detecting the rotation speed Nsec of the secondary pulley 66. Signal, the selected position from the inhibitor switch 48, and the throttle opening sensor 4 corresponding to the depression amount of the accelerator pedal operated by the driver.
5 to read the throttle opening TVO (or the opening of the accelerator pedal) from the engine control unit 27 for controlling the fuel injection amount and the ignition timing of the engine (not shown). In accordance with the state or the driver's request, the variable control of the speed ratio of the continuously variable transmission 57 and the engagement state of the lock-up clutch 51 of the torque converter 52 are controlled. In the present embodiment, the vehicle speed VSP is obtained by multiplying the secondary rotation speed Nsec by a predetermined conversion constant.
Engages the lock-up clutch 51 at or above the predetermined value Va.

The continuously variable transmission 57 includes a primary pulley 56
When the width of the V-shaped pulley groove is reduced, the contact radius of the V-belt 64 on the secondary pulley 66 side increases, so that a large gear ratio can be obtained.

The control for changing the widths of the V-shaped pulley grooves of the primary pulley 56 and the secondary pulley 66 is performed by controlling the hydraulic pressure of the primary pulley cylinder chamber 60 and the secondary pulley cylinder chamber 72.

The gear ratio control is performed by controlling a line pressure solenoid 44 of a hydraulic control valve 43, and the line pressure solenoid 44 is driven by a duty control or the like by a CVT control unit 41.

Next, an example of the shift control performed by the CVT control unit 41 will be described in detail with reference to the flowchart of FIG. Note that the flowchart of FIG. 2 is performed every predetermined time.

In step S1, the primary rotation speed Npri and the vehicle speed VSP (= secondary rotation speed Nsec) and the throttle opening TVO according to the driver's operation are read from the continuously variable transmission 57, and from the engine control unit 27. The engine speed Ne is read.

In step S2, a target value of the primary speed Npri is calculated from the vehicle speed VSP and the throttle opening TVO based on the speed change map shown in FIG. 3, and then the target speed ratio is calculated from the target value and the secondary speed Nsec. RT
O is calculated.

The shift map of FIG. 3 shows the throttle opening TV
The target input rotational speed Ne corresponding to the vehicle speed VSP is set in advance between the highest High line and the lowest Line using O as a parameter.

In step 3, the required line pressure PL is calculated so that the contact friction force between the primary pulley 16 and the secondary pulley 66 and the V-belt 64 becomes an optimum value. Then, the process proceeds to a step 4, wherein the line pressure solenoid 44 is driven at a predetermined duty ratio, and the primary pulley 5 is driven.
6. By controlling the line pressure PL supplied to the cylinder chambers 60 and 72 of the secondary pulley 66, the frictional force between the primary pulley 56, the secondary pulley 66 and the V belt 74 is set to an optimum value according to the operation state. .

The line pressure solenoid 44 controls the hydraulic pressure supplied from the oil pump 49 to the hydraulic control valve 4.
3 is adjusted to a required line pressure via a pressure control valve (not shown) and a constant pressure valve (not shown).

In FIG. 4, reference numeral 10 denotes an engine, 11 denotes an intake passage, 12 denotes an air cleaner, 13 denotes a throttle valve, 14 denotes a fuel injector of each cylinder, and 15 denotes an exhaust passage.

Reference numeral 16 denotes a radiator. The cooling water of the engine 10 passes through the radiator bypass passage 21 when the thermostat 20 on the radiator 16 side is closed.
When the thermostat 20 is opened, it is circulated through the radiator 16.

Reference numeral 17 denotes a heater device for heating the passenger compartment. Engine coolant is introduced into the heater core 18 of the heater device 17, and the heater core 19 is driven by driving the heater fan 19.
Air exchanged with the cooling water of No. 8 is blown into the vehicle interior.

When a heater switch (not shown) is turned on, a heater controller 28 for driving the heater fan 19 is turned on when the room temperature is equal to or lower than a predetermined temperature, based on a signal from a room temperature sensor 29 for detecting the temperature in the vehicle compartment. When the air flow reaches a high level and reaches a predetermined temperature, the heater fan 1
9 is controlled to be low (weak).

Reference numeral 22 denotes a rotation speed sensor for detecting the rotation speed of the engine; 23, an air flow sensor for detecting the intake air amount of the engine; 24, a throttle valve opening sensor for detecting the opening of the throttle valve 13; A water temperature sensor 26 for detecting a cooling water temperature is an oxygen concentration sensor for detecting an oxygen concentration in exhaust gas, and these signals are sent to an engine control unit 27 together with signals from a vehicle speed sensor and an ignition switch (not shown).

The engine control unit 27 controls the fuel injector 1 based on signals from the sensors.
4, the fuel injection amount control, that is, the air-fuel ratio control is performed.

The injector 14 faces the combustion chamber from the combustion chamber ceiling wall, and a homogeneous combustion region where the fuel injection timing of the injector 14 is the intake stroke and a stratified combustion region where the fuel injection timing of the injector 14 is the compression stroke are set. . In the stratified combustion region, the air-fuel ratio becomes lean to 30 to 40.

When the engine is operated at an air-fuel ratio (lean burn) leaner than the stoichiometric air-fuel ratio, the calorific value of the engine decreases. For this reason, in a cold region, if the operation by the lean burn is continued in an operating state where the gear ratio is large and the engine speed is low, the engine calorific value is insufficient, and the heating of the vehicle compartment using the engine cooling water temperature is sufficiently performed. It may not be possible.

When the outside air temperature is low and the air volume of the heater fan 19 is large, the change in the cooling water temperature becomes large, and hunting may occur in the control for switching the air-fuel ratio between lean and stoichiometric.

In response to this, the present invention determines that the CVT control unit 41 is in an operating state in which a high heating capacity is required, and when the high heating capacity is required, the engine water temperature Tw is lower than the low gearing water temperature level. The target transmission ratio RTO of the step transmission 17 is corrected to be low.

The shift map of FIG. 3 includes an engine coolant temperature Tw.
(Indicated by a dashed line) in the operating state in which the engine water temperature Tw exceeds the low-gearing water temperature level (indicated by a solid line in FIG. 3). Is set higher by a predetermined value.

The flowchart of FIG. 5 shows the engine coolant temperature Tw.
Shows a routine for switching the target speed ratio RTO of the continuously variable transmission 17 in accordance with the CVT control unit 4.
1 is executed at regular intervals.

At steps 11 and 12, the engine cooling water temperature TWN is read and set as the starting cooling water temperature TWINT set at the time of starting the engine.

In step 13, the starting water temperature TWINT
The starting water temperature threshold INTWLS (for example, -10 ° C)
Compare with

If the starting water temperature TWINT is equal to or higher than the starting water temperature threshold value INTWL, it is determined that the outside air temperature is not low and the required heating capacity is small.
Proceed to.

In step 14, the target input rotational speed Ne is searched for in the shift map shown in FIG.

In this case, since the engine speed is reduced without correcting the gear ratio to be low, the fuel efficiency is improved.

On the other hand, when the starting water temperature TWINT is lower than the starting water temperature threshold value INTWL, the outside air temperature is low and it is determined that a high heating capacity is required, and the routine proceeds to step 15.

The determination at the time of requesting the high heating capacity may be made by using the outside air temperature and the air volume of the heater fan 19 as parameters.

When the routine proceeds to step 15, it is determined whether or not the engine cooling water temperature TWN is in an operation state equal to or lower than the low gear water temperature level TWLO.

In an operating state in which the engine coolant temperature TWN has risen above the low geared coolant temperature level TWLO,
Proceeding to step 14, the target value of the target input speed Ne is searched for in the shift map shown in FIG.

Also in this case, the engine speed is reduced without correcting the gear ratio to be low, so that the fuel efficiency is improved.

When the engine coolant temperature TW is equal to or lower than the low gear water temperature level TWLO, the target value of the target input speed Ne is searched for in accordance with the shift line shown by the broken line in the shift map shown in FIG.

In this case, since the speed ratio is corrected to be low and the engine speed is increased, the calorific value of the engine 10 is increased, and the warming up of the engine 10 is promoted. Secure enough ability.

As another embodiment, the CVT control unit 41 sets the low gear water temperature level according to the cooling water temperature at the time of engine start, the outside air temperature, and the fan airflow of the heater fan 19 based on the table shown in FIG. May be.

FIG. 6 shows a low geared water temperature level TWL when the cooling water temperature and the outside air temperature at the time of engine start are respectively lower than predetermined values and the fan air volume is higher than the predetermined value.
H (for example, 82 ° C.), and when the fan air volume is weaker than a predetermined value, an intermediate low-gear water temperature level twlm (for example, 78 ° C.) is set. On the other hand, when the cooling water temperature at the time of starting the engine is higher than the predetermined value and the outside air temperature is lower than the predetermined value, a low geared water temperature level TWLS (for example, 75 ° C.) is set regardless of the fan air volume. ing.

As described above, the required low-gear water temperature level is increased by lowering the cooling water temperature at the time of engine start, the outside air temperature, or the fan airflow of the heater fan, thereby increasing the required level. The amount of heat generated by the engine is increased as the heating capacity increases, and sufficient heating capacity can be secured.

In the above-described embodiment, an example in which the continuously variable transmission 17 is constituted by a V-belt type is shown. However, although not shown, the same applies to a case where the continuously variable transmission 17 is constituted by a toroidal type. In addition, the present invention can be applied to an automatic transmission that switches a transmission gear via hydraulic pressure.

[Brief description of the drawings]

FIG. 1 is a system diagram of a transmission showing an embodiment of the present invention.

FIG. 2 is a flowchart illustrating an example of control performed by a CVT control unit.

FIG. 3 is a shift map showing a relationship between a vehicle speed VSP and a target input rotation speed Ne, similarly using the throttle opening TVO as a parameter.

FIG. 4 is a system diagram of the engine.

FIG. 5 is a flowchart showing an example of control performed by the CVT control unit.

FIG. 6 is a chart in which a low gear water temperature level is set in another embodiment.

[Explanation of symbols]

 10 Engine 17 Heater Device 18 Heater Core 19 Heater Fan 25 Water Temperature Sensor 26 Oxygen Concentration Sensor 27 Engine Control Unit 28 Heater Control Unit 41 CVT Control Unit 43 Hydraulic Control Valve 44 Line Pressure Solenoid 45 Throttle Opening Sensor 46 Primary Speed Sensor 47 Secondary Speed Number sensor 57 continuously variable transmission

Claims (5)

[Claims] 1. A shift control device for a vehicle, comprising: a heater device for heating a vehicle interior by radiating engine cooling water; and means for controlling a speed ratio of a transmission in accordance with an operating state of the vehicle. A high heating capacity demand determining means for determining when the heating capacity to be operated is higher than a predetermined value; an engine cooling water temperature detecting means for detecting an engine cooling water temperature; and an engine cooling water temperature equal to or lower than a low gear water temperature level when the high heating capacity is required. And a gear ratio correction means for correcting the gear ratio to be low during operation of the vehicle. 2. The shift control device for a vehicle according to claim 1, wherein the gear ratio correction means increases the low gear water temperature level when the coolant temperature at the time of starting the engine is low. 3. The vehicle according to claim 1, further comprising an outside air temperature detecting means for detecting an outside air temperature, wherein the speed ratio correction means increases the low gear water temperature level when the outside air temperature is low. Transmission control device. 4. A heater fan for transmitting heat radiation of the engine cooling water into a vehicle cabin, and a fan air volume detecting means for detecting a fan air volume of the heater fan, wherein the gear ratio correction means comprises a low gear when the fan air volume is large. The shift control device for a vehicle according to any one of claims 1 to 3, wherein the coolant temperature level is increased. 5. The shift control device for a vehicle according to claim 1, wherein the mixture supplied to the engine is controlled to a lean air-fuel ratio in a predetermined low speed range.