JP2015025381A - Start control device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a start control device of an internal combustion engine capable of realizing reliable start while ensuring drivability.SOLUTION: A start control device of an internal combustion engine permits start of cranking as a starting operation of the internal combustion engine by an operation of an ignition key under a condition that a shift position of an automatic transmission is in a non-travel range not permitting start of a vehicle. When shift change is performed from the non-travel range to a travel range during the cranking, the cranking is stopped when it is detected that a brake pedal is not operated, and the cranking is continued when the brake pedal is operated.

Description

  The present invention relates to an internal combustion engine start control device that performs control at the time of starting an internal combustion engine.

  Conventionally, in order to avoid the sudden start of the vehicle due to the start operation of the internal combustion engine, by the operation of the ignition key on the condition that the shift lever of the automatic transmission is in a position other than neutral, that is, the N range at the start stage. A technique that does not permit start of driving a starter motor is disclosed (for example, see Patent Document 1). Further, in general, in a vehicle equipped with an automatic transmission, the start of the internal combustion engine by the operation of the ignition key is permitted only when the shift lever is parked, that is, in a non-traveling range such as P range or N range, and cranking is started. On the other hand, the cranking is not started in the travel ranges such as the D range and the R range other than the non-travel range. In such vehicles, starting with the ignition key is permitted in the P range or N range, and after cranking has started, if a shift change to the driving range is performed during the cranking, energization of the starter motor is prohibited and starting. The vehicle cannot start without being able to start.

  Here, depending on the driver's preference, in order to speed up from the start of the internal combustion engine by the operation of the ignition key to the start of the vehicle as soon as possible, a shift change to the travel range is performed in anticipation of the timing at which the internal combustion engine reaches the complete explosion by the start. An operation may be performed.

  However, when the above-described operation is performed, the start cannot be performed as described above when the timing of the shift change is too early, and depending on the driver, it may be recognized as a start failure caused by the vehicle side.

  When the driver performs a shift operation with the intention of starting, engine start control is provided to permit engine start even at a shift position other than the N position.

Japanese Patent No. 4427677

  The present invention focuses on the above-described points, and an object of the present invention is to provide a start control device for an internal combustion engine that can realize a reliable start while ensuring drivability.

  In order to achieve such an object, the present invention takes the following measures.

  That is, the start control device for an internal combustion engine according to the present invention permits the start of the start operation of the internal combustion engine by operating the ignition key on the condition that the shift position of the automatic transmission is a non-traveling range in which the vehicle cannot be started. An engine start control device, wherein after the start operation is started, when the shift position is moved from the non-travel range to a travel range that can start the vehicle during the start period, the start is performed when the brake pedal is not operated. Is stopped and the start is continued when the brake pedal is operated.

  If this is the case, even if the shift position is accidentally moved to the travel range during the start period due to the driver's preference, the start is continued without being stopped, and the start operation of the internal combustion engine can be completed. It is possible to start at a desired timing without giving recognition of a start failure. At this time, since the driver is operating the brake pedal, it has been confirmed that the driver is correctly prepared for starting, so unintentional starting is effectively prevented. As a result, a start control device for an internal combustion engine capable of realizing a reliable start while ensuring drivability is provided.

  Further, in order to more effectively prohibit sudden start after the start operation is completed, the accelerator pedal is moved when the shift position is moved from the non-travel range to the travel range during the start period after the start operation is started. It is desirable to apply a mode in which the start is continued only when the is not operated.

  ADVANTAGE OF THE INVENTION According to this invention, the start control apparatus of the internal combustion engine which can implement | achieve a reliable start can be provided, ensuring drivability.

1 is a schematic configuration diagram according to an embodiment of the present invention. The figure which shows schematic structure of the internal combustion engine which concerns on the embodiment, a transmission, and a control apparatus. FIG. 3 is a schematic circuit diagram according to the embodiment. The flowchart which concerns on the same embodiment.

  An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an outline of an internal combustion engine mounted on a vehicle in the present embodiment. The internal combustion engine in the present embodiment is a spark ignition type 4-stroke gasoline engine, and includes a plurality of cylinders 1 (one of which is shown in FIG. 1). In the vicinity of the intake port of each cylinder 1, an injector 11 for injecting fuel is provided. A spark plug 12 is attached to the ceiling of the combustion chamber of each cylinder 1. The spark plug 12 receives spark voltage generated by the ignition coil and causes spark discharge between the center electrode and the ground electrode. The ignition coil is integrally incorporated in a coil case together with an igniter that is a semiconductor switching element.

  The intake passage 3 for supplying intake air takes in air from the outside and guides it to the intake port of each cylinder 1. On the intake passage 3, an air cleaner 31, an electronic throttle valve 32, a surge tank 33, and an intake manifold 34 are arranged in this order from the upstream.

  The exhaust passage 4 for discharging the exhaust guides the exhaust generated as a result of burning the fuel in the cylinder 1 from the exhaust port of each cylinder 1 to the outside. An exhaust manifold 42 and an exhaust purification three-way catalyst 41 are disposed on the exhaust passage 4.

  FIG. 2 shows an example of a drive system provided in the vehicle. This drive system includes a torque converter 7 and automatic transmissions 8 and 9. In particular, in the present embodiment, a forward / reverse switching device 8 using a planetary gear mechanism and a belt-type CVT (Continuously Variable Transmission) 9 which is a type of continuously variable transmission are adopted as components of the automatic transmissions 8 and 9. doing.

  The rotational torque output from the internal combustion engine is input from the crankshaft of the internal combustion engine to the pump impeller 71 on the input side of the torque converter 7 and transmitted to the turbine runner 72 on the output side. The rotation of the turbine runner 72 is transmitted to the drive shaft 94 of the CVT 9 via the forward / reverse switching device 8 and rotates the driven shaft 95 through a shift in the CVT 9. The rotation of the driven shaft 95 is transmitted to the output gear 101. The output gear 101 meshes with the ring gear 102 of the differential device, and rotates the axle 103 and the drive wheels (not shown) via the differential device.

  The torque converter 7 includes a lockup mechanism. The lock-up mechanism is known in this field, and a lock-up clutch 73 that fastens the input side and the output side of the torque converter 7 so as not to rotate relative to each other, and an operation for switching the connection of the lock-up clutch 73. A lock-up solenoid valve (not shown) for controlling the hydraulic pressure (hydraulic pressure) is used as an element. The lockup solenoid valve is a flow rate control valve that receives a control signal l and changes its opening.

  In a vehicle equipped with CVT 9, when the vehicle speed is a predetermined value (for example, 10 km / h) or more, the torque converter 7 is almost always locked up. When the vehicle speed is equal to or lower than the predetermined value, the lockup of the torque converter 7 is released. During lockup, the lockup clutch 73 is pressed against the torque converter cover 74 and rotates together with the torque converter cover 74. At the time of lockup, the speed ratio, which is the ratio of the output side rotational speed of the torque converter 7 to the input side rotational speed, is 1.

  In turn, the lock-up clutch 73 is separated from the torque converter cover 74 at the time of non-lock-up. At the time of non-lock-up, the torque of the internal combustion engine is transmitted from the torque converter cover 74 to the pump impeller 71 and the turbine 72 and is transmitted to the forward / reverse switching device 8. At the time of non-lock-up, the speed ratio of the torque converter 7 becomes smaller or larger than 1 depending on the driving state.

  In the forward / reverse switching device 8, the sun gear 81 communicates with the turbine runner 72, and the ring gear 82 communicates with the drive shaft 94. Between the planetary carrier 83 that supports the planetary gear 831 and the transmission case, a forward brake 84 that is a hydraulic clutch that can be connected and disconnected is provided. Further, a reverse clutch 85, which is a hydraulic clutch that can be connected and disconnected, is also interposed between the planetary carrier 83 and the sun gear 81 (or the output side of the torque converter 7).

  In the D range of the traveling range, the forward brake 84 is engaged and the reverse clutch 85 is disconnected. As a result, the rotation of the output shaft of the torque converter 7 is reversed and decelerated and transmitted to the drive shaft 94 for forward travel. In turn, in the R range, the reverse clutch 85 is engaged and the forward brake 84 is disconnected. As a result, the sun gear 81 and the planetary carrier 83 rotate integrally, and the output shaft of the torque converter 7 and the drive shaft 94 are directly connected to perform reverse travel. A solenoid valve (not shown) that controls the hydraulic pressure for driving the forward brake 84 or the reverse clutch 85 to connect / disconnect is a flow rate control valve that receives a control signal m and changes its opening.

  In the N range and P range, which are non-traveling ranges, both the forward brake 84 and the reverse clutch 85 are disconnected.

  The CVT 9 includes a driving pulley 91 and a driven pulley 92, and a belt 93 wound around the pulleys 91 and 92 as elements. The drive pulley 91 is disposed behind the movable sheave 912, a fixed sheave 911 fixed to the drive shaft 94, a movable sheave 912 supported on the drive shaft 91 via a roller spline so as to be displaceable in the axial direction. A hydraulic servo 913 is provided, and the gear ratio can be changed steplessly by operating the hydraulic servo 913 and displacing the movable sheave 912. The driven pulley 92 is disposed on the back of the movable sheave 922, a fixed sheave 921 fixed to the driven shaft 95, a movable sheave 922 supported on the driven shaft 95 via a roller spline so as to be axially displaceable. A hydraulic servo 923 is provided, and a belt thrust necessary for torque transmission is applied by operating the hydraulic servo 923 and displacing the movable sheave 922.

  The hydraulic fluid (hydraulic fluid) supplied to the forward brake 84 or the reverse clutch 85 for operating the travel range and the hydraulic fluid supplied to the hydraulic servos 913 and 923 for operating the gear ratio are used for the torque converter 7. It is common with the fluid to be used.

  A brake booster (not shown) is attached to the vehicle of this embodiment. The brake booster introduces intake negative pressure from a portion of the intake passage 3 downstream of the throttle valve 32, more specifically, from the surge tank 33, and uses the negative pressure to boost the pedaling force of the brake pedal. It is well known. The brake booster has a constant pressure chamber that stores negative pressure and a variable pressure chamber to which atmospheric pressure is applied, and the constant pressure chamber is connected to the surge tank 33 via a negative pressure line. The negative pressure line guides the intake negative pressure downstream of the throttle valve 32 to the constant pressure chamber. A check valve is provided on the negative pressure line to keep the negative pressure in the constant pressure chamber and prevent the positive pressure from being applied to the constant pressure chamber.

  When the brake pedal is not operated by the driver, the constant pressure chamber and the variable pressure chamber communicate with each other, and the variable pressure chamber is isolated from the atmospheric pressure. When the brake pedal is operated, the constant pressure chamber and the variable pressure chamber are interrupted, and the atmosphere is introduced into the variable pressure chamber. As a result, the pressure difference between the constant pressure chamber and the variable pressure chamber becomes a control pressure that boosts the depression force of the brake pedal. The brake pedal force amplified by the brake booster is converted into a so-called brake master pressure in a master cylinder (not shown), and brakes such as a brake caliper and a wheel cylinder are passed through a hydraulic circuit (not shown). To a device (not shown). In the present embodiment, a brake master pressure sensor (not shown) for detecting the fluid pressure called the brake master pressure in real time is provided.

  A starter motor 61, a pinion gear 62 and a drive plate 63 for cranking the internal combustion engine when the internal combustion engine is started are provided between the internal combustion engine and the torque converter 7. More specifically, a pinion gear 62 is provided at the tip of the drive shaft of the starter motor 61, and the pinion gear 62 meshes with a ring gear 64 on the outer periphery of the drive plate 63 to rotationally drive the drive plate 63.

  An ECU (Electronic Control Unit) 0 serving as a control device for an internal combustion engine according to the present embodiment is a microcomputer system having a processor, a memory, an input interface, an output interface, and the like. The control program is stored in advance, and when it is executed, it is read into the memory and decoded by the processor.

  The internal combustion engine, the CVT 9, the starter motor 61, and the like are controlled by the ECU 0.

  The input interface includes a vehicle speed signal a output from a vehicle speed sensor that detects the actual vehicle speed of the vehicle, a crank angle signal b output from an engine rotation sensor that detects the rotation angle and engine speed of the crankshaft, and depression of an accelerator pedal. From an accelerator opening signal c output from a sensor that detects the amount or the opening of the throttle valve 32 as an accelerator opening (in other words, a required load), a sensor (or shift position switch) for knowing the range of the shift lever The output shift range signal d, the intake air temperature / intake pressure signal e output from the temperature / pressure sensor for detecting the intake air temperature and the intake negative pressure in the intake passage 3 (especially the surge tank 33), and the temperature of the internal combustion engine. Cooling water temperature signal f output from the water temperature sensor for detecting the suggested cooling water temperature, intake camshaft or exhaust Cam angle signal g output from the cam angle sensor at a plurality of cam angles of the camshaft, hydraulic fluid temperature signal p output from the hydraulic fluid temperature sensor for detecting the temperature of the hydraulic fluid, brake switch output from the brake switch A signal r or the like is input.

  From the output interface, a motor drive signal h for energizing the starter motor 61 for cranking, an ignition signal i for the igniter 13 of the spark plug 12, a fuel injection signal j for the injector 11, a throttle valve 32, and An opening control signal k for the idle speed control valve 36, an opening control signal l for the lockup solenoid valve, and an opening control signal m for the solenoid valve for switching connection / disconnection of the forward brake 84 or the reverse clutch 85. , The gear ratio control signal n and the like are output to the CVT 9.

  In this embodiment, an auxiliary signal h1 for energizing the starter motor 61 is output separately from the motor drive signal. The auxiliary signal h1 will be described later.

  The processor of the ECU 0 interprets and executes a program stored in the memory in advance, calculates operation parameters, and controls the operation of the internal combustion engine. The ECU 0 acquires various information a, b, c, d, e, f, g, p, q, and r necessary for operation control of the internal combustion engine through the input interface, and knows the engine speed and the cylinder 1 Estimate the amount of intake air to be filled. Based on the engine speed and intake air amount, etc., the required fuel injection amount, fuel injection timing (including the number of times of fuel injection for one combustion), fuel injection pressure, ignition timing, and torque converter 7 lock-up are adjusted. Various operation parameters such as whether or not to perform the transmission and the gear ratio of the automatic transmissions 8 and 9 are determined. As the operation parameter determination method itself, a known method can be adopted. The ECU 0 applies various control signals i, j, k, l, m, n and h, h1 corresponding to the operation parameters via the output interface.

  Therefore, the ECU 0 as the start control device for the internal combustion engine according to the present embodiment sets the ignition key on the condition that the shift position of the automatic transmissions 8 and 9 is a non-traveling range in which the vehicle cannot start, that is, the N range or the P range. The cranking start which is the starting operation of the internal combustion engine by the operation is allowed. When the shift change from the non-traveling range to the D range or R range, which is the traveling range, is performed during cranking, the cranking is stopped if at least the brake switch signal r detects that the brake pedal is not operated. When the brake pedal is operated, cranking can be continued. In the present embodiment, cranking is continued only when the accelerator pedal is not operated by the accelerator opening signal c during the shift change.

  The above control is realized by the circuit shown in FIG. The figure shows a motor drive circuit 60 provided between the ECU 0 and the starter motor 61. The motor drive circuit 60 is provided with an auxiliary switch in addition to the relay switch 65 and the non-traveling range switch 66 that are conventionally provided. The relay switch 65 is a normal switch having a main switch 65a and an electromagnetic coil 65b. When a weak voltage as a motor drive signal h is applied from the ECU 0 to the electromagnetic coil 65b, the electromagnetic coil 65b functions as an electromagnet. 65a is driven to the short-circuit side, and the starter motor 61 is energized. The non-traveling range switch 66 is a normal switch that is turned on when the ECU 0 detects a shift range signal d indicating that it is the P range or the N range from the shift position sensor. When the non-traveling range switch 66 is ON, energization from the ECU 0 to the electromagnetic coil 65b is permitted.

  The auxiliary switch 67 is branched from the non-traveling range switch 66. That is, in this embodiment, even when the non-traveling range switch 66 is OFF and energization is not permitted, energization from the ECU 0 to the electromagnetic coil 65b is permitted when the auxiliary switch 67 is turned ON. In addition, the auxiliary switch 67 is illustrated as an example of an NPN transistor. That is, when a weak voltage as the auxiliary signal h1 is applied from the ECU 0 to the base of the auxiliary switch 67, energization between the emitter and the collector is permitted. That is, at this time, even if the non-traveling range switch 66 is OFF, energization from the ECU 0 to the electromagnetic coil 65b is permitted.

  In the present embodiment, the following control as shown in the flowchart of FIG. 4 is executed by the motor drive circuit 60 described above when the internal combustion engine is started by the operation of the ignition key, that is, when cranking.

  When the ignition key is operated to the start position by the driver (step S1), cranking by energizing the starter motor 61 is started only when the shift position is the non-traveling range N range or P range ( Step S3). In other words, the voltage that is the motor drive signal h is applied from the ECU 0 to the relay switch 65, and the starter motor 61 is driven. Here, during the cranking, if the shift position is not shifted to the D range or R range as the travel range (step S4), the cranking is completed after the internal combustion engine reaches a complete explosion (step S5). (Step S6), the vehicle enters an idle state where the vehicle can start immediately. However, when the shift position is shifted to the D range or R range, which is the travel range, during cranking due to the driver's desire to start the vehicle as soon as possible, etc., the non-travel range switch 66 is It becomes OFF. Therefore, if the brake pedal is ON, that is, it is operated (step S7), and the accelerator pedal is not OFF, that is, not operated (step S8), the non-traveling range switch 66 is turned off. Cranking is stopped by stopping the energization of the starter motor without applying a voltage to the electromagnetic coil 65b (step S9).

  However, if the brake pedal is on, ie, operated (step S7), and the accelerator pedal is off, ie, not operated (step S8), a voltage is applied from the ECU 0 to the base of the auxiliary switch 67. Then, the auxiliary signal h1 is output to the auxiliary switch 67. Thereby, even if the non-running switch 66 is turned OFF, the energization, that is, the cranking to the starter motor 61 is continued (step S10). Thereafter, similarly to the above-described case where the shift position is not changed, after the internal combustion engine reaches a complete explosion (step S5), the cranking is completed (step S6), and the vehicle enters an idle state where the vehicle can start.

  Here, as an example, the timing at which the auxiliary signal h1 is transmitted in the present embodiment is as shown in FIG. 4 and is actually a shift change from when the shift range signal d indicating the shift position change to the non-traveling range is detected. The timing until this is done. However, as a matter of course, the auxiliary signal h1 may be transmitted when it is confirmed that the brake pedal has been turned on, that is, operated from the start of cranking, and the accelerator pedal is turned off, that is, not operated.

  With this configuration, in this embodiment, even if the shift position is moved to the travel range before the completion of cranking according to the driver's preference, the start is continued without stopping if the vehicle is in a state where it cannot start. Since the start operation of the internal combustion engine can be completed, the driver can start at a desired timing without recognizing the start failure. As a result, a reliable start can be realized while ensuring drivability.

  In particular, in this embodiment, since the condition that the accelerator pedal is not operated is also a condition for continuing the cranking, an emergency start immediately after the completion of the cranking operation is more effectively prohibited, and safety is improved more effectively. I'm coughing.

  Although the embodiment of the present invention has been described above, the specific configuration of each unit is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, an aspect in which a starter motor and a drive plate are provided as a configuration for starting the internal combustion engine has been disclosed, but of course, it is provided coaxially on the crankshaft of the internal combustion engine and controls power generation as well. A motor generator may be applied. Further, specific modes of the internal combustion engine and the automatic transmission are not limited to those of the above-described embodiment, and various modes including the existing ones can be applied.

  In addition, the specific configuration of each part is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  The present invention can be used as a start control device for an internal combustion engine that controls cranking when the internal combustion engine is started.

0 ... Start control device (ECU) of internal combustion engine
61 ... Starter motor 66 ... Non-traveling range switch 67 ... Auxiliary switch c ... Accelerator opening signal h ... Motor drive signal h1 ... Auxiliary drive signal r ... Brake switch signal

Claims (2)

An internal combustion engine start control device that permits the start operation of the internal combustion engine by operating the ignition key on the condition that the shift position of the automatic transmission is a non-traveling range in which the vehicle cannot be started,
When the shift position is moved from the non-traveling range to a traveling range where the vehicle can be started during the starting period after starting operation is started,
An internal combustion engine start control device characterized in that the start is stopped when a brake pedal is not operated and the start is continued when the brake pedal is operated. After the start operation starts, when the shift position is moved from the non-travel range to the travel range during the start period,
2. The start control device for an internal combustion engine according to claim 1, wherein the start is continued only when the accelerator pedal is not operated.

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