JP2011111896A - Idling stop control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an idling stop control device allowing determination giving no uncomfortable feeling to a driver when determining whether or not to stop an engine automatically before vehicle stop. <P>SOLUTION: The idling stop control device, when a brake pedal is depressed during traveling at a low speed not higher than a predetermined vehicle speed, associates a depression amount and a vehicle speed at the time point of the depression with a result whether the vehicle results in stopping with the depression operation, learns them in a map (a learning technique S18), and when the brake pedal is depressed during low speed traveling, determines based on the learning result stored in the map whether or not to stop the internal combustion engine automatically (a determinator S13). Accordingly, automatic engine stop is inhibited from being performed during low speed traveling despite the intention of the driver operating the brake pedal. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an idle stop control device that is applied to an idle stop vehicle that can automatically stop an engine before the vehicle stops when the brake pedal is depressed during low-speed traveling.

  Patent Literature 1 and the like describe an idle stop vehicle that automatically stops the engine when the vehicle stops. Specifically, it is automatically stopped on condition that the brake pedal is depressed and the vehicle speed is zero. However, in recent years, in order to further improve fuel efficiency, when the brake pedal is depressed more than a determination value during low-speed traveling, control has been proposed in which the vehicle speed is automatically stopped before the vehicle speed becomes zero and the vehicle stops.

JP 2000-199444 A

  However, in the above-described control that automatically stops when the brake depression amount is equal to or greater than the determination value during low-speed traveling, the following problem occurs.

  In other words, since the correlation between the amount of brake depression and the degree of braking effectiveness differs from vehicle to vehicle, setting the automatic stop judgment value uniformly for all vehicles will result in the same braking effectiveness. Since the amount of depression at that time differs from vehicle to vehicle, the frequency of automatic stop varies from vehicle to vehicle. For example, even if the brake pedal is depressed to stop the vehicle, there is a vehicle with a low automatic stop frequency, such as the vehicle does not stop automatically due to insufficient depression, or the vehicle is automatically stopped when the brake pedal is depressed with the intention of decelerating although there is no intention to stop. There are vehicles with a high frequency of automatic stops.

  In other words, when determining whether to automatically stop before the vehicle speed reaches zero (before stopping), the vehicle will not make an optimal determination according to how the brakes are applied, which makes the driver feel uncomfortable. There is concern about giving it.

  The present invention has been made to solve the above-described problems, and its purpose is to make a determination that does not give the driver an uncomfortable feeling when determining whether or not to automatically stop the engine before stopping. An idle stop control device is provided.

  Hereinafter, means for solving the above-described problems and the operation and effects thereof will be described.

  According to the first aspect of the present invention, the present invention is applied to an idle stop vehicle capable of automatically stopping the engine before the vehicle stops when the brake pedal is depressed during low speed traveling at a predetermined vehicle speed or less, and during low speed traveling. When the brake pedal is depressed, the learning means for learning by associating the depression amount and vehicle speed at the time of depression and the result of whether the vehicle has stopped with the depression operation, and the brake pedal during the low-speed traveling And a determination unit that determines whether or not to automatically stop the engine based on a learning result obtained by the learning unit.

  According to the above-described invention, when the brake pedal is depressed during low-speed traveling, learning is performed by associating the depression amount and vehicle speed at the depression point with the result of whether or not the vehicle has come to stop with the depression operation. In other words, since the driver should be manipulating the depression amount in consideration of the actual braking effectiveness, the depression amount and the vehicle speed when depressing with the intention of stopping are learned in association with the result that the vehicle has come to a stop. . In addition, although there is no intention of stopping, the amount of depression and the vehicle speed when depressing with the intention of decelerating are learned in association with the result that the vehicle has not stopped.

  Therefore, according to the above-described invention for determining whether or not to automatically stop during low-speed driving based on these learning results, even if the brake pedal is depressed with the intention of stopping, there is a sense of incongruity that the vehicle does not stop automatically due to insufficient depression. Although there is no intention, it is possible to make an automatic stop determination that does not give a strange feeling that the brake pedal is automatically stopped when the brake pedal is depressed with the intention of decelerating.

  In addition, when the result of whether or not the vehicle has come to a stop is different for the same stepping amount and vehicle speed area, the frequency at which the vehicle has stopped and the frequency at which the vehicle has not stopped are calculated, It is only necessary to learn which frequency is high.

  The invention according to claim 2 is characterized in that the learning means performs different learning for each driver even in the same vehicle.

  By the way, in addition to the fact that the correlation between the amount of brake depression and the degree of braking effectiveness varies from vehicle to vehicle, even if the vehicle is the same, the amount of depression when the vehicle is intended to stop because the brake pedal is operated by each driver. In addition, when the vehicle is intended to decelerate without stopping, the amount of depression differs for each driver. For this reason, there is a concern that even if an automatic stop determination without any sense of incongruity is made for a certain driver, the sense of discomfort may be given to other drivers.

  In the above-mentioned invention in view of this point, when learning by associating the depression amount and the vehicle speed when the brake pedal is depressed and the stop result, different learning is performed for each driver, the automatic stop according to the driver's habit described above Since the determination can be performed, the above-mentioned concerns can be solved, and automatic stop determination that does not give the driver a sense of incongruity can be promoted.

  In the invention according to claim 3, when the driver's intention to accelerate is detected during the low-speed traveling from when the brake pedal is depressed until the vehicle stops, the learning associated with the depression is prohibited. Features.

  Here, after the brake pedal is depressed during low speed driving, the driver may indicate an intention to accelerate such as depressing the accelerator pedal.In this case, even if the vehicle stops after indicating the intention to accelerate, Correlation between the amount of depression and the vehicle speed at the time of depression of the vehicle and the stopping result is extremely low.

  In the above invention in view of this point, when the driver's intention to accelerate is detected after the brake pedal is depressed during low speed travel, the learning associated with the depression is prohibited. As described above, it is possible to avoid learning a stop result having a low correlation.

  In the invention according to claim 4, when the stepping amount and the vehicle speed of the region learned to have stopped are the stopping stepping amount and the stopping vehicle speed, the determination means is not less than the stopping stepping amount and not more than the stopping vehicle speed. The unlearned area is determined to automatically stop the engine.

  Even if it is an unlearned area, if it is an area that is greater than or equal to the stepped amount of the area learned to stop and is less than the vehicle speed, there is a high possibility that the vehicle will stop. According to the above invention for determining to stop, appropriate automatic stop determination can be performed at an early stage before learning is completed in all regions.

  In the invention of claim 5, when the stepping amount and the vehicle speed of the region learned not to stop are the non-stopping stepping amount and the non-stopping vehicle speed, the determination means is less than the non-stopping stepping amount and An unlearned region below the non-stop vehicle speed is determined not to automatically stop the engine.

  Even if it is an unlearned area, it is highly possible that the vehicle is not intended to stop if it is an area that is greater than the amount of depression and less than the vehicle speed of the area that has been learned to have not stopped. According to the above-described invention for determining not to automatically stop the engine, an appropriate automatic stop determination can be performed at an early stage before learning is completed in all the regions.

1 is a schematic diagram showing an idle stop vehicle to which an idle stop control device is applied in an embodiment of the present invention. The time chart which shows the timing t1 when the vehicle speed shifted to low speed driving | running | working, and the brake operation was first carried out, and the stop timing t2. In one Embodiment of this invention, the map where the learning result used for determination of whether to perform engine automatic stop was memorize | stored was stored. The flowchart which shows the procedure of a learning process and an automatic stop process in one Embodiment of this invention.

  Hereinafter, an embodiment embodying an idle stop control device according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing an idle stop vehicle 10 to which an idle stop control device according to the present embodiment is applied. The vehicle 10 is equipped with an internal combustion engine (engine 11) as a travel drive source. . An automatic transmission device 12 is attached to the output shaft of the engine 11, and the automatic transmission device 12 automatically changes gears by changing the gear position in accordance with the amount of operation of the accelerator pedal 13 by the vehicle driver and the vehicle speed. It is.

  Detection values of the accelerator sensor 14 and the vehicle speed sensor 15 are input to the electronic control unit (ECU 20) mounted on the vehicle 10, and the ECU 20 calculates the depression amount and the vehicle speed based on these detection values. Further, the ECU 20 receives a detection value of the brake sensor 17 that detects an operation stroke amount of the brake pedal 16, and the ECU 20 describes the depression amount of the brake pedal 16 (hereinafter referred to as “brake depression amount”) based on the detection value. ) Is calculated.

  The ECU 20 (idle stop control device) electronically controls the operation of a fuel injection valve (not shown) mounted on the engine 11 and satisfies an automatic stop condition such as an automatic stop permission described in detail later. If so, the idle stop control is performed so that the engine 11 is automatically stopped by stopping the fuel injection from the fuel injection valve.

  When a predetermined automatic start condition is satisfied, a starter motor (not shown) is driven to control the engine 11 to start automatically. As a specific example of the automatic start condition, the brake depression amount is zero (the brake pedal 16 is not operated), and a shift lever (not shown) for operating the automatic transmission 12 can travel. It is operated to the drive position and the accelerator pedal 13 is operated.

  ECU20 performs the following learning processes, when it transfers to the low speed driving state below predetermined vehicle speed from the vehicle driving state faster than predetermined vehicle speed (for example, 20 km / h). That is, the brake depression amount when the brake pedal 16 is first depressed after the low-speed traveling and the vehicle speed at that time, and whether the vehicle has come to stop with the depression operation (whether the vehicle speed has reached zero) Learning by associating with the results of.

  The solid line in FIG. 2 shows an example in which after the actual vehicle speed becomes equal to or lower than the predetermined vehicle speed Vth and the vehicle shifts to low speed, the brake is first depressed at time t1 and then stopped at time t2. Also, an alternate long and short dash line in FIG. 2 shows an example in which the brake is first depressed at time t1, and then the vehicle driver depresses the accelerator pedal 13 to increase the vehicle speed and the vehicle does not stop.

  And the map M shown in FIG. 3 is memorize | stored in the rewritable memory which ECU20 has. The map M is configured by dividing the brake depression amount and the vehicle speed into a plurality of areas ARx. And in each area | region ARx, the stop frequency and re-running frequency which are demonstrated below are memorize | stored, and these memory | storage contents are learned. The “stop frequency” refers to the frequency at which the vehicle stops due to the brake depression operation during low-speed traveling as indicated by the solid line in FIG. The above-mentioned “re-running frequency” means that the driver depresses the brake during low-speed running as indicated by the alternate long and short dash line in FIG. 2, but then the driver's intention to continue running without stopping (running intention to continue) is detected and stopped. It is the frequency that did not reach. The area with halftone dots in FIG. 3 is an area where the stopping frequency is higher than the rerunning frequency, and the area where no halftone dots are attached has a rerunning frequency higher than the stopping frequency. It is an area.

  As a specific example of detecting the intention to continue running, when the vehicle speed increase (acceleration) is detected after time t1, when the depression of the accelerator pedal 13 is detected after time t1, the amount of steering wheel operation after time t1 is detected. For example, it may be detected that the (steering angle) is operated by a predetermined amount or more.

  The learning is performed for each driver. Specifically, the driver operates the selection switch 18 (see FIG. 1) provided in the passenger compartment so that the current driver is instructed to select himself / herself. The ECU 20 stores a map M for each driver instructed to be selected from the selection switch 18, and learns about the map M instructed to be selected.

  Then, using the map M learned in this way, the ECU 20 determines whether or not to execute the automatic engine stop as follows. That is, when the brake pedal 16 is depressed during low-speed traveling, the brake depression amount and the vehicle speed area ARx at the time t1 are the areas where the stop frequency is high in the map M (the halftone dots in FIG. 3 are added). In the case of (region), it is permitted to automatically stop the engine 11. If other automatic stop conditions are also satisfied during low-speed traveling, the engine 11 is automatically stopped even before the vehicle stops.

  The above-mentioned “other automatic stop conditions” are mainly that the driver does not intend to continue running. Specifically, the accelerator pedal 13 is not operated, the vehicle speed is not increased (accelerated), steering. For example, the operation amount (steering angle) of the steering wheel is not operated more than a predetermined amount.

  FIG. 4 is a flowchart showing a procedure of the learning process and the automatic stop process by the microcomputer of the ECU 20, and the process is repeatedly executed at a predetermined cycle.

  First, in step S10 shown in FIG. 4, the current vehicle speed, brake depression amount, and driver information are acquired based on signals output from the vehicle speed sensor 15, the brake sensor 17, and the selection switch 18. In a succeeding step S11, it is determined whether or not learning conditions are satisfied and learning to the map M can be executed. In the present embodiment, the vehicle speed is a low-speed traveling state equal to or lower than the predetermined vehicle speed Vth, the driver does not intend to continue traveling, the brake pedal 16 is depressed for a predetermined time or more, or any of them is satisfied. Satisfying one of these is the “learning condition”. Then, when it is determined that the learning condition is not satisfied and the learning execution is impossible (S11: NO), the processing of FIG. 4 is once ended.

  If it is determined that the learning condition is satisfied and learning can be executed (S11: YES), in the subsequent step S12, a target driver map M is selected based on the driver information acquired in step S10. Furthermore, it is determined which area ARx of the selected map M the vehicle speed and the amount of depression acquired in step S10 correspond to, and the determined area is determined as the learning area ARx.

  In subsequent step S13 (determination means), it is determined whether or not the learning content of the area determined in step S12 is an “automatic stop area” described later. If it is determined that the vehicle is in the automatic stop region (S13: YES), automatic engine stop is permitted. In step S14, if the above-mentioned “other automatic stop conditions” are also satisfied, the fuel injection from the fuel injection valve is stopped and the engine 11 is automatically stopped even during low-speed traveling. Controls the operation of the fuel injection valve. If it is determined that the vehicle is not in the automatic stop region (S13: NO), in subsequent step S15, it is determined whether or not the intention to continue traveling is detected, such as when the driver has an intention to accelerate before stopping.

  If it is determined that there is no intention to continue traveling (S15: NO), in the subsequent step S16, the number of times that the vehicle has stopped (vehicle speed zero) due to the depression of the brake acquired in step S10 is increased, and the subsequent step S18. In (learning means), learning is performed so as to increase the stop frequency. On the other hand, if it is determined that there is an intention to continue running (S15: YES), in the subsequent step S17, the number of times that the vehicle has not stopped (vehicle speed zero) due to the depression of the brake acquired in step S10 is increased. In the subsequent step S18, learning is performed to increase the re-running frequency.

  In subsequent step S19, it is determined that the number of learning in the learned area is greater than or equal to a predetermined number (S19: YES), and the number of reruns counted in step S18 is greater than the number of stoppages and the rerun rate (frequency) is greater than or equal to the predetermined number. If so (S20: YES), the corresponding area ARx is set as an automatic stop prohibition area (S23). On the other hand, if the number of re-runs is greater than the number of stops and the re-run rate (frequency) is less than a predetermined value (S20: NO), the corresponding area ARx is set as an automatic stop area (S21).

  In this specification, the stepping amount and the vehicle speed in the region set as the automatic stop region in step S21 are referred to as the stopping stepping amount and the stopping vehicle speed. Further, the stepping amount and the vehicle speed in the region set as the automatic stop prohibition region in step S23 are referred to as a non-stopping stepping amount and a non-stopping vehicle speed. Then, in step S22 following step S21, an unlearned area that is greater than or equal to the stop depression amount and less than or equal to the stopped vehicle speed, or an area in which the number of learning is less than a predetermined value is set as an automatic stop area and automatic stop is permitted. . In step S24 following step S23, an unlearned area that is greater than or equal to the non-stop stepping amount and less than or equal to the non-stop vehicle speed, or an area in which the number of learning is less than a predetermined value is set as an automatic stop prohibition area and automatically stopped. Is prohibited.

  Note that for the unset areas that are not set in any of steps S21, S22, S23, and S24, the determination in step S13 is performed according to the initial settings. For example, an area with a halftone dot in FIG. 3 is initialized as an automatic stop area, and an area without a halftone dot is initially set as an automatic stop prohibition area.

  As described above, according to the present embodiment, when the brake pedal 16 is depressed during low-speed traveling, the depression amount and the vehicle speed at the depression step are associated with the result of whether or not the vehicle has stopped due to the depression operation. Learning from the map M, and based on the learning result, it is determined whether or not to automatically stop the engine during low-speed traveling. Therefore, it does not give a sense of incongruity that even if the brake pedal 16 is depressed for the purpose of stopping, it will not be automatically stopped due to insufficient depression, or that it will not be automatically stopped when the brake pedal 16 is depressed for the purpose of deceleration although there is no intention of stopping. In addition, it is possible to determine whether to stop the engine automatically during low-speed driving.

  Furthermore, in this embodiment, since the learning is performed with a different map M for each driver, the engine automatic stop determination according to the driver's habit can be performed, so that the suppression of the uncomfortable feeling can be promoted.

  Further, in the present embodiment, when the driver's intention to accelerate is detected after the brake pedal 16 is depressed during low-speed traveling until the vehicle stops, the learning associated with the depression is prohibited. Further, it is possible to avoid learning a stop result having a low correlation with the vehicle speed.

  Furthermore, in the present embodiment, an unlearned area that is greater than or equal to the stop depression amount and less than or equal to the stopped vehicle speed, or an area where the number of learnings is less than a predetermined value is set as an automatic stop area and automatic stop is permitted. Further, an unlearned area that is greater than the non-stop stepping amount and less than the non-stop vehicle speed, or an area where the number of learning is less than a predetermined number is set as an automatic stop prohibition area and automatic stop is prohibited. Therefore, the engine automatic stop determination according to the driver's habit can be performed without waiting for learning to be performed a predetermined number of times.

(Other embodiments)
The present invention is not limited to the description of the above embodiment, and may be modified as follows.

  In the above embodiment, the area with the halftone dots in FIG. 3 is initially set as an automatic stop area, and the area without the halftone dots is set as the automatic stop prohibition area, and the map M is initialized. However, all areas may be initially set as automatic stop prohibited areas, or all areas may be initially set as automatic stop areas.

  Here, even if the brake depression amount and the vehicle speed at that time are the same, the history of the vehicle speed up to that vehicle speed, that is, whether the vehicle has suddenly decelerated to the predetermined vehicle speed Vth, or is slowly decelerated to the predetermined vehicle speed The frequency of whether to stop depends on whether the vehicle reaches Vth. Therefore, in determining whether or not the learning condition is satisfied in step S11 of FIG. 4, a determination threshold value for determining whether or not to learn according to the vehicle speed history may be changed. Further, a determination threshold value for determining whether or not to automatically stop the engine may be changed according to the vehicle speed history. Moreover, you may make it learn for every said vehicle speed log | history.

  DESCRIPTION OF SYMBOLS 11 ... Engine (internal combustion engine), 16 ... Brake pedal, 20 ... ECU (idle stop control apparatus), S13 ... Determination means, S18 ... Learning means.

Claims (5)

When the brake pedal is depressed during low-speed traveling below a predetermined vehicle speed, this is applied to idle stop vehicles that can automatically stop the engine before the vehicle speed reaches zero and stops,
When the brake pedal is depressed during the low-speed traveling, a learning unit that learns by associating a depression amount and a vehicle speed at the depression point with a result of whether or not the vehicle has stopped with the depression operation;
Determination means for determining whether or not to automatically stop the engine based on a learning result by the learning means when a brake pedal is depressed during the low-speed traveling;
An idle stop control device comprising:   The idle stop control device according to claim 1, wherein the learning unit performs different learning for each driver even in the same vehicle.   3. The learning according to claim 1 or 2, wherein when the driver's intention to accelerate is detected after the brake pedal is depressed during the low-speed traveling until the vehicle stops, learning associated with the depression is prohibited. An idle stop control device according to claim 1. When the stepping amount and the vehicle speed of the area learned to have stopped are the stopping stepping amount and the stopping vehicle speed,
The idle stop according to any one of claims 1 to 3, wherein the determination unit determines to automatically stop the engine for an unlearned region that is greater than or equal to the stop depression amount and less than or equal to the stop vehicle speed. Control device. When the amount of depression and the vehicle speed of the area learned not to stop are the non-stop depression amount and the non-stop vehicle speed,
5. The determination unit according to claim 1, wherein the determination unit determines that the engine is not automatically stopped for an unlearned region that is less than the non-stop stepping amount and less than the non-stop vehicle speed. Idle stop control device.

Images