JP2008100586A - Start control device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a start control device for a vehicle for achieving accurate start control even when vehicle weight is not detected. <P>SOLUTION: A vehicle weight detection means detects vehicle weight according to vehicle acceleration and road gradient, and fuel supply quantity to a gear stage and an engine at the start of a vehicle is determined according to the detected vehicle weight. When the vehicle weight is not detected by the vehicle weight detection means, the fuel supply quantity at the start of the vehicle is set to the fuel supply quantity for the minimum vehicle weight, and when the road gradient detected by a road gradient detection means exceeds a threshold, the gear step at the start of a vehicle is set to the lowest stage. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle start control device provided with an automatic transmission.

  The automatic transmission for a vehicle automatically changes and sets an optimal gear stage based on values such as a vehicle traveling speed and an accelerator opening. Further, it is known that a mechanical clutch using a dry clutch plate has high transmission efficiency and improves the fuel consumption rate. Therefore, a drive device in which a mechanical automatic clutch is combined with a transmission has been widely used for cargo vehicles.

In a vehicle equipped with such a drive device, when the gear speed changes, the engine speed increases unnecessarily when the mechanical automatic clutch connection operation is associated with the fuel supply amount to the engine. Scarecrows, deceleration shocks, etc. are prevented. For example, an invention is known in which a fuel injection amount to an engine is determined based on the rotational speed of an engine and the output shaft of a clutch, and a mechanical automatic clutch is connected.
JP 2004-270624 A

  However, in the conventional output control for determining the rotational difference between the engine and the clutch and setting the fuel injection amount to the engine, the control according to the vehicle weight is not performed. Therefore, in a freight vehicle in which a large difference in vehicle weight occurs between a loaded state and a unloaded state, a problem may occur when changing gears.

  In other words, if the output control at the time of gear change is set to a preferable setting for empty load driving, the fuel injection amount becomes insufficient when the load is loaded, and the driver feels that the acceleration is insufficient. If the preferred setting is used, the fuel is excessive when the vehicle is idle, and the engine is likely to run out. Therefore, it has been considered to provide vehicle weight detection means for detecting the vehicle weight and to control the vehicle drive device based on the value of the vehicle weight detected by the vehicle weight detection means.

  However, since the vehicle weight detection means calculates the vehicle weight while running the vehicle, it takes time until the vehicle weight is detected. Therefore, immediately after the vehicle starts traveling, the vehicle weight may not be detected and accurate control may not be performed.

  Therefore, if the control set for empty load is applied until the vehicle weight is detected, for example, when the vehicle is actually loaded with a load and it is going to start on a slope, it becomes impossible to start. There is a fear. In the meantime, if the control set for loading is applied, if the vehicle is not actually loaded, the engine output at the start becomes too large, and the engine speed increases unnecessarily. This may cause inconvenience in driving.

  The present invention solves the above-described problem and provides a vehicle start control device that can perform accurate start control even when the vehicle weight is not detected in a vehicle start control device that performs control in consideration of the vehicle weight. The purpose is to provide.

In order to solve the above-described problems, the present invention has a vehicle start control device configured as follows.
That is, in the vehicle start control device of the present invention, when the vehicle weight is not detected by the vehicle weight detection means, the fuel supply amount at the start of the vehicle is set to the fuel supply amount when the vehicle weight is the smallest, and the road gradient When the road gradient detected by the detection means exceeds the threshold, the gear stage at the start is set to the minimum number of stages.

  This will be described in detail below.

  The start control device is a start control device for a vehicle engine in which a mechanical automatic clutch is assembled between an engine and a transmission, a fuel supply means for supplying fuel to the engine, and a vehicle weight detection for detecting the weight of the vehicle. And a road gradient detecting means for detecting the road gradient, and in accordance with the vehicle weight detected from the normal vehicle weight detecting means, the selection of the gear stage at the start of the vehicle and the fuel supply to the engine by the fuel supply means The supply amount is determined.

  The engine is a vehicle engine and includes fuel injection (supply) means. The output of the engine is adjusted with the fuel injected from the fuel injection means. The fuel injection means injects a predetermined amount of fuel to the engine in accordance with an instruction from the start control device when the vehicle starts. A transmission is assembled to the engine via a mechanical automatic clutch. Note that a transmission using a fluid torque converter instead of a mechanical automatic clutch may be used.

  The vehicle controlled by the start control device is a cargo vehicle, but may be a passenger vehicle. The engine is preferably a diesel engine, but may be a gasoline engine.

  The transmission includes a gear switching unit, and the gear switching unit is operated according to an instruction from the transmission control device, and the gear stage is automatically switched. The speed change control device is connected to a vehicle speed sensor, an accelerator opening sensor, a gear position detecting means for detecting a set gear position, etc. Instruct the switching unit to switch gears.

  The mechanical automatic clutch includes a dry clutch plate, an actuator using hydraulic pressure or pneumatic pressure, a pressing spring, and the like. The clutch plate is pressed against the output shaft side of the engine, for example, a flywheel by the spring force of the pressing spring, whereby the rotation of the engine is transmitted to the transmission. This is a state where the clutch is engaged. When the actuator is operated and the clutch plate is pulled away from the flywheel, the connection between the engine and the transmission is cut off. This is a so-called clutch disengaged state.

  The engine start control device is connected to various detection means (sensors) including a vehicle weight detection means, and operates the engine and the transmission in cooperation with the speed change control device to perform start control according to the vehicle weight. The vehicle weight detected by the vehicle weight detection means is a value of the entire vehicle including the weight of the luggage loaded on the vehicle.

  For example, when it is determined that the vehicle weight is small and no load is loaded, the start control based on the vehicle weight is set to the second gear as usual when starting, and the rate of increase in the fuel supply amount at the start ( The fuel injection amount per unit time) is set to a small value. On the other hand, when it is determined that the vehicle weight is large and the load is loaded, the gear stage at the start is set to the first speed, and the increase rate of the fuel supply amount at the start is set to a large value.

  The start control device further includes a vehicle weight determination unit that determines whether or not the vehicle weight is detected by the vehicle weight detection unit, and a gradient determination that determines whether or not the road gradient detected by the road gradient detection unit exceeds a threshold value. If the vehicle weight is not detected, control different from the above is performed. Here, the case where the vehicle weight is not detected by the vehicle weight detection means may be, for example, immediately after the start of traveling, when a sufficient number of acceleration starts are not performed, or when a malfunction occurs in the device. .

  That is, when the vehicle weight is not detected, the fuel supply amount at the start of the vehicle is set to the fuel supply amount when the vehicle weight is the smallest, that is, the fuel supply amount set for empty load, and the road gradient detecting means When the road gradient detected by the vehicle exceeds the threshold, the gear stage at the time of starting is set to the minimum number of stages, that is, the first speed.

  Here, when the vehicle weight is not detected by the vehicle weight detection means, the fuel supply amount at the time of starting the vehicle is set to the fuel supply amount when the vehicle weight is the smallest. Regardless, always start with the fuel supply set for empty cargo.

  When the road gradient exceeds the threshold value, the threshold is set when the gear stage at the start is set to the minimum number of stages. The threshold value indicates that the vehicle loads the maximum load and sets the fuel supply amount for empty load. Is set to the 2nd speed, the maximum slope that cannot be climbed is the maximum value, and any slope below that is set. Thereby, if the road gradient exceeds the threshold value, the vehicle always starts at the first speed regardless of whether the vehicle is in an empty state or a loaded state.

  The vehicle weight detection means calculates the vehicle weight based on the road gradient value detected by the road gradient detection means and the vehicle acceleration value at the gradient detected by the acceleration detection means.

  Specifically, the inclination of the vehicle is obtained by an inclination detection means provided in the vehicle, and the inclination is regarded as a road inclination. Then, when the vehicle is accelerated on a road having such a gradient, the vehicle weight is calculated from the fuel supply amount at that time, that is, the fuel consumption amount, and the acceleration of the vehicle detected by the acceleration detecting means. The calculation is performed continuously while the vehicle is running, the average value is obtained, and the calculated value is converged. Instead of the acceleration detected by the acceleration detecting means, a speed change amount per time may be used.

The vehicle start control device according to the present invention has the following effects.
In a vehicle having a start control device, start control according to the vehicle weight is performed, so that optimal start is performed regardless of the load.

  Further, in the case of a vehicle having a start control device, when the vehicle weight is not detected by the vehicle weight detecting means, the fuel supply amount is set for empty load. You can start without any problems.

  Furthermore, if there is a slope on the road and the value of the slope exceeds the threshold value, the lowest gear stage, for example, 1st gear is set, so the fuel supply set for empty load even in the loaded state You can start with certainty. On the other hand, if the road gradient is smaller than the threshold value, the vehicle can start without any trouble with the second gear stage even in a loaded state.

An embodiment of a start control device according to the present invention will be described with reference to the drawings.
FIG. 1 shows a vehicle drive device 4 including a start control device 3. The vehicle drive device 4 includes an engine 6, a transmission 8, a mechanical automatic clutch 10, a start control device 3, a shift control device 5, and the like. FIG. 5 shows a vehicle 100 equipped with the vehicle drive device 4. The vehicle 100 is a freight vehicle and includes a loading platform 102 at the rear of the vehicle.

  The engine 6 is a diesel engine, and is provided with a fuel injection device 12 as fuel supply means as shown in FIG. A transmission 8 is assembled behind the engine 6 via a mechanical automatic clutch 10.

  The mechanical automatic clutch 10 includes a dry clutch plate 16, a pressing spring 18 that presses the clutch plate 16, an actuator 20 provided at the center of the clutch plate 16, and the like. The clutch plate 16 is normally pressed against a flywheel (not shown), which is an output shaft of the engine 6, by a pressing spring 18, whereby the rotation of the engine 6 is transmitted to the transmission 8 via the mechanical automatic clutch 10. Communicated.

  A hydraulic device 22 is connected to the actuator 20. When the hydraulic device 22 is driven by the drive unit 24, the actuator 20 is operated by the hydraulic pressure, and the clutch plate 16 is separated from the flywheel against the pressing spring 18. . When the clutch plate 16 is pulled away from the flywheel, the connection between the output shaft of the engine 6 and the input shaft of the transmission 8 is cut off. Further, the mechanical automatic clutch 10 has a half-clutch state which is intermediate between a state where the clutch is connected and a state where the clutch is disconnected.

  The transmission 8 has a plurality of transmission gears (not shown) inside, and has a gear switching unit 14 that changes the meshing of the transmission gears at the top. The gear switching unit 14 is connected to the drive unit 24, and the gear unit of the transmission 8 is switched by switching the meshing of the transmission gear (selection, shift operation) by driving the drive unit 24.

  The engine output control device 3 and the speed change control device 5 are connected to various detection means (sensors) attached to the vehicle drive device 4 and the vehicle 100, and are linked to each other based on signals from the detection means. General control for running 100 is performed.

  Specifically, the start control device 3 and the transmission control device 5 include vehicle weight detection means 7, vehicle speed detection means 26, engine speed detection means 27, and clutch plate 16 as shown in FIGS. The clutch rotational speed detecting means 28 for detecting the rotational speed of the clutch, the gear position detecting means 29, the accelerator pedal detecting means 52, the shift lever detecting means 54, and the detecting means for detecting the brake state (FIG. The vehicle weight is detected by the vehicle weight detection means 7 and the optimum fuel injection amount and gear stage are determined based on each signal, and the vehicle 100 is started.

  As shown in FIG. 2, the vehicle weight detection means 7 includes an inclination detection device 30 (road gradient detection means) and an acceleration detection device 32 (acceleration detection means), and detects the value of the entire vehicle weight including the load.

The inclination detection device 30 is a detection device that detects the inclination of the vehicle 100 in the front-rear direction. The inclination of the vehicle 100 detected by the inclination detection device 30 is regarded as a value equal to the gradient of the road on which the vehicle 100 is traveling as shown in FIG. The acceleration detection device 32 detects an acceleration generated in the vehicle 100 when the vehicle 100 starts or when the vehicle 100 decelerates and accelerates during traveling. (See Figure 5 for both)
The vehicle weight detection means 7 uses the gradient detected by the inclination detection device 30, the fuel consumption when the vehicle 100 is accelerated on a road having such a gradient, and the acceleration detected by the acceleration detection device 32 at that time. Thus, the weight of the vehicle 100 is calculated. The vehicle weight is determined by performing the calculation many times during traveling and taking the average.

  In normal start control by the start control device 3 in consideration of the vehicle weight, when the vehicle weight is small, the second speed gear (which is a normal setting) is selected, and the fuel supply amount at start is reduced. On the other hand, when the vehicle weight is large, as the vehicle weight increases, more fuel is supplied and the gear stage is set to the first speed.

  Further, as shown in FIG. 3, the start control device 3 includes vehicle weight determination means 9 and gradient determination means 11, and in addition to the above-described normal start control, the vehicle weight detection means 7 does not detect the vehicle weight. The start control corresponding to is performed.

  The vehicle weight discriminating means 9 discriminates whether or not the vehicle weight detecting means 7 has detected the vehicle weight. The gradient discriminating means 11 discriminates whether or not the road gradient exceeds the threshold value α using the inclination of the vehicle 100 detected by the inclination detection device 30. The threshold value α is an arbitrary value set with the maximum value being the maximum gradient value that the vehicle 100 loaded with the maximum load capacity can climb at the second speed and with the fuel supply amount set for empty load.

  Next, the start control when the vehicle weight is not detected, which the start control device 3 has, will be described with reference to the flowchart of FIG.

  First, the inclination detection device 30 detects the inclination of the vehicle 100 and detects the road gradient (F-1). Next, the vehicle weight determination means 9 determines whether or not the vehicle weight is detected by the vehicle weight detection means 7 (F-2).

When it is determined in F-2 that the vehicle weight is detected, the start control device 3
The start gear stage corresponding to the vehicle weight is selected (F-3), and the fuel supply amount at the start corresponding to the vehicle weight is determined (F-4).

  On the other hand, if the vehicle weight discriminating means 9 determines that the vehicle weight is not detected by the vehicle weight detecting means 7 in F-2, the fuel supply amount at the start is set to the fuel supply amount based on the empty load. (F-5). Then, the gradient determining means 11 determines whether the gradient of the road on which the vehicle 100 is traveling is equal to or less than the threshold value α (F-6), and when it is determined that the gradient is equal to or less than the threshold value α, the start control is performed as it is. . On the other hand, if the gradient determining means 11 determines in F-6 that the gradient exceeds the threshold value α, the gear stage at the start is set to the first speed.

  As described above, according to the vehicle 100 including the start control device 3, it is possible to start according to the vehicle weight. Even if the vehicle weight is not detected, the gear stage is set to the first speed if the fuel supply amount set for empty load is set and the gradient exceeds the threshold value α. Therefore, the vehicle 100 can start without causing engine idling in an empty state, generates less noise, and even in a loaded state, starts at the second speed if the gradient is small, When the gradient is large, the vehicle starts at the first speed, so that the vehicle can be started reliably without being disabled, and safe driving with less driver fatigue can be realized.

The figure which shows one Embodiment of the vehicle drive device using the start control apparatus concerning this invention. The block diagram which shows the structure of a start control apparatus. The block diagram which shows a start control apparatus. The flowchart which shows start control. The figure which shows a vehicle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 ... Start control apparatus 4 ... Vehicle drive device 6 ... Engine 7 ... Vehicle weight detection means 8 ... Transmission 9 ... Vehicle weight discrimination means 10 ... Mechanical automatic clutch 11 ... Gradient discrimination means 12 ... Fuel injection device 14 ... Gear switching unit DESCRIPTION OF SYMBOLS 16 ... Clutch plate 18 ... Pressing spring 20 ... Actuator 22 ... Hydraulic device 24 ... Drive unit 26 ... Vehicle speed detection means 27 ... Engine speed detection means 28 ... Clutch speed detection means 29 ... Gear stage detection means 30 ... Inclination detection device ( Road slope detection means)
32. Acceleration detection device (acceleration detection means)
52 ... Accelerator pedal detection means 54 ... Shift lever detection means 100 ... Vehicle 102 ... Loading platform

Claims (2)

A vehicle start control device in which a mechanical automatic clutch is assembled between an engine and a transmission,
Fuel supply means for supplying fuel to the engine;
Vehicle weight detection means for detecting the weight of the vehicle;
Road gradient detecting means for detecting the road gradient,
According to the vehicle weight detected from the vehicle weight detection means, the selection of the gear stage at the time of vehicle start, and the amount of fuel supplied to the engine by the fuel supply means,
When the vehicle weight is not detected from the vehicle weight detection means, the fuel supply amount at the time of starting the vehicle is set to the fuel supply amount when the vehicle weight is the smallest, and the road gradient detected by the road gradient detection means is A start control apparatus for a vehicle, characterized in that when the threshold value is exceeded, the gear stage at the time of start is set to a minimum number of steps. The vehicle weight detection means comprises acceleration detection means for detecting the acceleration of the vehicle,
The vehicle weight is calculated from the road gradient detected by the road gradient detection means and the acceleration of the vehicle detected by the acceleration detection means when the vehicle is accelerated on a road having the gradient. Vehicle start control device.

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