JP2004052617A - Idling stop device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for allowing the restart of an engine with natural driving operation in a vehicle with no clutch pedal in the state of the engine being automatically stopped by idling/stop control. <P>SOLUTION: In the state of the engine being stopped by idling/stop control, a driver strongly pedals a brake pedal to execute automatic restart of the engine. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an improvement in an apparatus for automatically stopping an engine of an automobile in an idling state under a certain condition. In particular, the present invention relates to a control logic for restarting an automatically stopped engine by a simple and natural operation.
[0002]
[Prior art]
2. Description of the Related Art An idle stop device that automatically stops an engine of a vehicle stopped during traveling after the engine becomes idling and a certain condition is satisfied without operating a key switch has become widespread. This idle stop device is often configured to automatically stop the engine and then automatically restart the engine when a clutch pedal is depressed or other predetermined operation is performed. ing.
[0003]
Idle stop devices have come to be used especially in large vehicles such as buses and trucks. It is widely used because it operates automatically when passengers get on and off at a stop or when the road is congested. Such an idle stop device has the advantages of reducing exhaust gas and reducing fuel consumption without having to operate the key switch each time, and is economical and environmentally friendly. It is effective for Since the device including the means for automatically restarting is simple in the starting operation, there is an advantage that the driver rarely cancels the idle stop device and travels.
[0004]
Such an idle stop device has been widely used, and the user's reputation and opinions have been taken in, and various improvements have been made to the operation state of the device. Among them, a device disclosed in Japanese Patent Application Laid-Open No. 2000-16122 is known as a device for setting a certain condition at the time of restarting after an idle stop device is operated to reduce a sense of discomfort in driving. . Further, in the case of a so-called automatic vehicle without a clutch pedal, depressing the clutch pedal cannot be used as a condition for restarting the vehicle. No. 1,413,671.
[0005]
Japanese Patent Application Laid-Open No. 2001-207784 (Applicant, Toyota) discloses that as a condition for restarting an engine automatically stopped by an idle stop device, the brake pedal is once released and then the brake pedal is depressed. The control logic which makes this the starting condition is disclosed. It is described that this is intended to clarify the intention of the driver to restart by once releasing the brake pedal, and to prevent the engine from restarting against the intention of the driver.
[0006]
In addition, Japanese Patent Application Laid-Open No. 2001-289081, which is a prior application of the applicant of the present application, requires that the brake pedal be depressed with a predetermined pressure or more for safety when restarting an automatically stopped engine. Is described.
[0007]
On the other hand, in commercial vehicles such as buses and trucks, a device is widely known in which a control circuit automatically controls gear selection and switching of a transmission using input information such as an engine rotation speed, a vehicle speed, and a depression amount of an accelerator pedal. ing. Such devices used for commercial vehicles do not eliminate clutch pedals as unnecessary devices, and those having an automatic transmission and those having a clutch pedal are widely used. In a vehicle equipped with an automatic transmission provided with a clutch pedal, when the driver determines that it is necessary, the driver disengages the clutch by depressing the clutch pedal, and overrides the automatic control by the control circuit to execute the shift operation. Can be. Particularly in the start operation of a vehicle, a professional driver has gained a good reputation as a device that can start and accelerate the vehicle as intended by skillfully controlling the half-clutch state by operating a clutch pedal.
[0008]
[Problems to be solved by the invention]
A so-called manual shift vehicle not equipped with an automatic transmission has a clutch pedal. Alternatively, there is a vehicle equipped with an automatic transmission, but having a clutch pedal as described above. In these vehicles, the engine stopped by the idle stop device can be restarted by depressing the clutch pedal. This is a natural operation in the flow of the driving operation. In order to start the vehicle, it is necessary to depress the clutch and set the transmission to the starting gear, which is a necessary operation, and restarting the engine in conjunction with this operation requires extra operation to restart the engine. You will not need it.
[0009]
However, in a vehicle without a clutch pedal, operating the start switch provided at the left foot position as described above as a conventional example in order to restart the engine stopped by the idle stop device is an operation for starting the vehicle. It is an extra operation inside. This is an extra operation even if the start switch is operated in some way by hand, not by the left foot. This does not result in an automatic restart in a strict sense, but also causes an unnatural operation in the flow of the driving operation.
[0010]
It is not desirable that the engine automatically stopped by the idle stop device be restarted against the driver's will. That is, it is necessary that an operation based on the driver's clear intention to restart the engine be a trigger for engine restart. Furthermore, by restarting the engine without performing any operation, control logic that may cause the vehicle to start accidentally cannot be tolerated.
[0011]
The present invention has been made in such a background, and an object of the present invention is to improve conditions for automatically stopping rotation by an idle stop device and restarting an engine. An object of the present invention is to provide an idle stop device that can restart an engine by a natural operation in a flow of a driving operation. An object of the present invention is to provide a device capable of restarting an engine without operating a start switch in any way. Moreover, an object of the present invention is to provide a device in which the engine is not automatically restarted against the driver's will. SUMMARY OF THE INVENTION It is an object of the present invention to provide a device that prevents a vehicle from starting by mistake when an engine is restarted.
[0012]
[Means for Solving the Problems]
The present invention focuses on the fact that the driver is stepping on the brake pedal in the natural flow of the driving operation when restarting the engine that is automatically stopped by the control of the idle stop device. is there. That is, the present invention is configured such that, when the engine is stopped by the control of the idle stop device, the driver depresses the brake pedal, and the engine is automatically restarted when the brake pedal is further depressed. It was made.
[0013]
That is, according to the present invention, the key switch is operated when the vehicle speed is substantially zero, the engine rotation speed is equal to or lower than a predetermined value, and an engine stop condition including a condition that the transmission is set to the neutral position is satisfied. Means for stopping the engine at least, and means for restarting the engine without operating a key switch when predetermined engine restart conditions are satisfied after the engine is stopped under the control of this means. In the stop device, the restart condition includes:
(I) the transmission is in a neutral position,
(Ii) the brake pedal is depressed strongly,
It is characterized by including.
[0014]
With this configuration, the driver does not need to perform a special operation such as operating another start switch provided so as to be operated with the left foot, in order to restart the engine. In addition, with this configuration, when the engine is restarted, the brake pedal is depressed and a corresponding brake pressure is generated, and the vehicle is started in a safe direction without a risk of suddenly starting. is there.
[0015]
The above condition (ii) that the brake pedal is strongly depressed is described in more detail. From the state where the brake pedal is depressed at the first predetermined pressure (p ₁ ), the second predetermined pressure (p ₂ > p ₁ ) It is desirable to have a configuration that includes a state in which the transition to is performed. The first predetermined pressure (p ₁ ) and the second predetermined pressure (p ₂ ) are values to be individually selected according to the characteristics of each vehicle. To illustrate this first predetermined pressure (p ₁₎ is 30% to 60% of the braking pressure of the maximum brake pressure at which depresses the brake pedal to the maximum. To illustrate the second predetermined pressure (p _2), it is also set to the greater pressure value than the first brake pressure to a brake pressure of 55% to 95% of the maximum brake pressure. Such operation of the brake pedal is not an unnatural operation as a brake operation performed by the driver while the vehicle is stopped. Such operation of the brake pedal is an operation that the driver can perform consciously.
[0016]
This control logic is used as a condition for restarting the engine automatically stopped by the idle stop device as disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 2001-207844 (applicant, Toyota). Obviously, the purpose and configuration of the control logic are different from the control logic of releasing the brake pedal once and then depressing the brake pedal. The control logic of the present invention does not require the brake pedal to be released once.
[0017]
The present invention is effective when implemented in a vehicle not equipped with a clutch pedal as described in the above-described conventional device, but is equipped with a clutch pedal and automatically executes an engine restart when the clutch pedal is depressed. It is also possible to use the present invention together with a vehicle provided with a control logic. Further, even when the present invention is applied to a vehicle not equipped with a clutch pedal, the start switch operated by the left foot described in the above-described conventional apparatus can be omitted. It is also possible. Rather, as a product to be actually manufactured, there may be a case where a design in which the control logic of the present invention is added in combination with a start switch using a foot switch which is conventionally used and used by a user is not abolished.
[0018]
After the engine is started by the means for automatically restarting, the brake pedal is temporarily released in a state where the vehicle speed is substantially zero, the engine rotation speed is equal to or lower than a predetermined value, and the transmission is in the neutral position. A structure may be provided that includes means for automatically stopping engine rotation when the driver steps again. In other words, if the driver wants to stop the engine again after the conditions described above are satisfied and the engine is restarted, the brake pedal must be released once without operating the engine key switch, and By stepping on the pedal, the engine can be stopped under the control of the idle stop device.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 is a block diagram of a main part of an apparatus according to an embodiment of the present invention.
[0020]
FIG. 1 shows a connection relationship between an idle stop device embodying the present invention and a related control circuit. That is, the idle / stop control circuit 11 is constituted by a program control circuit (CPU). The idle / stop control circuit 11 can exchange signals with an engine control circuit 12 constituted by another program control circuit (CPU) and an automatic transmission control circuit 13 which is another program control circuit (CPU). It is connected to the. Information about the vehicle speed sensor 14 and the foot switch 15 is input to the idle / stop control circuit 11. Here, the feature of the present invention resides in that information of the two brake signals 16a and 16b is input.
[0021]
That is, in this embodiment, a first brake pressure switch which operates at a brake pressure of 50% of its maximum value and a second brake pressure switch which operates at 80% of its maximum value are provided. Signals from the pressure switches are input as a brake signal (a) and a brake signal (b), respectively.
[0022]
Further, the idle / stop control circuit 11 sends a control signal to the shift control circuit 17 and sends an output signal to the starting relay 18 and the indicator 19. Power is supplied to the idle / stop control circuit 11 from the power supply via the key switch 20 and the system switch 21, and a control signal indicating the state is input from the system switch 21.
[0023]
The operation of such a device will be described. When starting operation, the key switch 20 is operated, the start relay 18 is operated, and the starter 23 of the engine 24 is driven. As a result, the engine 24 starts. The engine control circuit 12 controls the governor 25 to adjust the rotation speed.
[0024]
When the driving stoppage is performed and the vehicle stops, if the engine stop condition by idle stop is satisfied, the engine is automatically stopped. This is because the vehicle speed generated by the vehicle speed sensor 14 is zero, the speed change lever 1 is in the neutral position from the automatic speed change control circuit 13, the rotation speed is substantially in the idling state from the engine control circuit 12, When an "idle stop permission signal", which satisfies conditions under which the control circuit 12 can cause other engines to idle-stop, specifically, conditions such as battery, engine temperature, and fuel, arrives, This is executed by the stop control circuit 11 sending a stop request signal to the engine control circuit 12. This stops the engine rotation.
[0025]
When the engine stops rotating, the driver lightly presses the brake pedal as a normal operation. This is, for example, a state in which the vehicle approaches a preceding vehicle on a congested road and temporarily stops for safety prevention. Alternatively, if it is a route bus, it is in a state of stopping at a stop and watching passengers get on and off. Even if the driver does not step on the brake pedal, the parking brake (not shown) can be operated if the driver wants to keep the vehicle stopped.
[0026]
Here, when the driver wants to start the vehicle, the foot switch 15 may be operated as before, but in the device of the present invention, when the brake pedal is strongly depressed, the brake signal (a) first arrives, and then the brake signal is applied. When the signal (b) arrives, the idle / stop control circuit 11 performs a series of starting operations and starts the engine again. This restart can be performed without operating the brake pedal. For example, when the vehicle is stopped by the parking brake (not shown) as described above, it is not necessary to operate the brake pedal. At this time, the engine in the idle stop state can be restarted by operating the foot switch 15 with the left foot.
[0027]
The shift lever 1 is temporarily locked during a period in which the restart operation is performed. This is an operation of the above-mentioned prior application which is not directly related to the present invention. However, briefly, the idle / stop control circuit 11 shifts to the shift control circuit 17 when the restart is executed. By sending a lock signal, the shift control circuit 17 drives the solenoid 5 to insert the pin 4 into the hole 6 between the movable member 2 and the fixed member 3 as described above, thereby mechanically fixing the shift lever 1. Control in such a manner that unnecessary operation of the shift lever is prohibited while maintaining the state.
[0028]
After the engine is started by the means for automatically restarting the vehicle according to the embodiment of the present invention, the vehicle speed is substantially zero, the engine speed is equal to or lower than a predetermined value, and the transmission is in the neutral position. When the brake pedal is once released and depressed again, for example, in a state where the idle stop condition is satisfied, for example, the engine rotation can be automatically stopped again.
[0029]
FIG. 2 is a flowchart of the operation of the main part of the idle stop control circuit of the device according to the present invention according to the present invention. When the engine is automatically stopped by the idle stop control, the transmission is in the neutral position, and when the brake is depressed at a pressure of 50% or more, the basic conditions for restart are satisfied. I do. Then, when the brake is further depressed at a pressure of 85% or more or the foot switch is operated, the restart procedure is automatically executed.
[0030]
【The invention's effect】
According to the present invention, in the flow of the driving operation, the engine can be restarted by the natural driving operation of strongly pressing the brake pedal. The present invention eliminates the need to perform extra operations to restart the engine. Moreover, according to the present invention, the driver's will is clearly reflected by strongly depressing the brake pedal, and the engine is restarted. In the present invention, since the brake pedal is depressed at the time of restart, the vehicle does not start erroneously when the engine is restarted.
[Brief description of the drawings]
FIG. 1 is a block diagram of an apparatus according to an embodiment of the present invention.
FIG. 2 is a control flowchart of a main part of the idle stop control circuit according to the embodiment of the present invention;
[Explanation of symbols]
REFERENCE SIGNS LIST 1 shift lever 2 member linked with shift lever 3 fixing member 4 pin 5 solenoid 6 hole 7 lever 8 fulcrum 11 idle / stop control circuit 12 engine control circuit 13 automatic shift control circuit 14 vehicle speed sensor 15 foot switch 16 brake signal 17 shift control Circuit 18 Starting relay 19 Indicator 20 Key switch 21 System switch 23 Starter 24 Engine 25 Governor

Claims (3)

When the vehicle speed is substantially zero, the engine speed is equal to or lower than a predetermined value, and the engine stop condition including the condition where the transmission is set to the neutral position is satisfied, the engine is stopped even if the key switch is not operated. An idle stop device comprising: means for restarting the engine without operating a key switch when a predetermined engine restart condition is satisfied after stopping the engine under the control of the means.
In the restart condition, (i) the transmission is in the neutral position,
(Ii) the brake pedal is depressed strongly,
An idle stop device comprising: The condition (ii) includes a state in which it is detected that the brake pedal has shifted from a state in which the brake pedal is depressed at a _first predetermined pressure (p ₁ ) to a second predetermined pressure (p ₂ > p ₁ ). Item 1. The idle stop device according to Item 1. After the engine is started by the means for automatically restarting, the brake pedal is once released in a state where the vehicle speed is substantially zero, the engine speed is equal to or lower than the predetermined value, and the transmission is in the neutral position. 2. The idle stop device according to claim 1, further comprising means for automatically stopping engine rotation when the vehicle is depressed again.

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