JP2008038872A - Electronic control method for throttle and electronical control throttle device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To favorably maintain an engine driving state by positively avoiding an engine stall caused by dropping of an engine speed, in an engine system equipped with an electronical control throttle device. <P>SOLUTION: In the throttle electronic control method carried out by the electronically controlled throttle device 1A carrying out opening and closing control of the throttle 3 via an actuator 7 by a command of an electronic control unit 10A, the electronic control unit 10A detects a neutral switch output signal, an engine speed sensor signal, and a vehicle speed sensor signal. If a shift position of a transmission is in a gear connected state, a vehicle speed is a predetermined determination traveling speed or more, and an engine seed is lower than a predetermined engine speed having a danger of causing an engine stall, throttle control is carried out to maintain an engine speed of a predetermined target engine speed or more to avoid an engine stall. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electronic throttle control method and an electronic control throttle device, in which a throttle installed in an intake system of a vehicle engine is opened and closed by an electronic control system. In particular, the engine speed is excessive during engine operation. The present invention relates to an electronic throttle control method and an electronic control throttle device for avoiding an engine stall that occurs due to a sudden decrease.

  In recent years, instead of mechanically opening and closing the throttle by the driver's accelerator operation, the electronic control system is used to electronically control the engine with high accuracy in order to improve vehicle fuel efficiency and driving performance. An electronically controlled throttle device that opens and closes automatically is widespread, and is described, for example, in Japanese Patent Laid-Open No. 5-240073. As shown in FIG. 4, the electronically controlled throttle device 1B is attached to an actuator 7 and an accelerator 9 for opening and closing the throttle 3 provided in the intake pipe of the throttle body 2 to a target opening position. An electronic control unit 10B that sends a required drive signal to the actuator 7 based on the accelerator opening data output from the accelerator opening sensor 8 and the throttle opening data from the throttle opening sensor 14 is provided.

  In an engine system having such an electronically controlled throttle device 1B, the electronic control unit 10B detects the accelerator opening and the engine load state, and throttles the engine operating state based on these data. Control to correct the opening is performed.

However, when the load amount in the engine operating state changes suddenly or travels without the accelerator operation, the control by the electronic control unit 10B does not follow, or there is a difference between the predicted value and the actual value in the control. In some cases, the engine speed drops suddenly and the engine stalls.
JP-A-5-240073

  The present invention is intended to solve the above-described problems, and in an engine system equipped with an electronically controlled throttle device, it is possible to reliably avoid an engine stall that occurs due to a drop in engine rotation speed. It is an object to be able to maintain the engine operating state well.

  Therefore, according to the present invention, an electronic throttle control method is provided in an electronically controlled throttle device that controls opening and closing of a throttle via an actuator by a control signal calculated by an electronic control means based on a detection signal from a predetermined detection means. In the control method, the predetermined detection means includes a neutral switch, an engine rotation speed sensor, and a vehicle speed sensor, the transmission is in a gear-connected state at the shift position, the vehicle speed is equal to or higher than a predetermined determination travel speed, and the engine Throttle control is performed so that the engine rotation speed is maintained at or above a predetermined target rotation speed for avoiding engine stall when the rotation speed is lower than a predetermined determination rotation speed at which engine stall may occur. did.

  As described above, the engine control speed is monitored by the electronic control unit, and the throttle opening is controlled so that the engine speed does not decrease excessively, so that the trouble that causes the engine stall can be effectively avoided. .

  Further, the electronic control means calculates a difference between the detected engine rotational speed and the target rotational speed to obtain a rotational speed deviation, and a throttle that is preset as an appropriate value according to the amount of the deviation. By driving the actuator so as to achieve the operating speed, the engine rotational speed can be appropriately controlled by the throttle operation, and the occurrence of engine stall can be avoided more reliably.

  Further, a throttle device that controls opening and closing of an engine throttle via an actuator by a control signal from an electronic control unit (CPU), and a neutral switch position for confirming that the transmission is in the shift position and the gear is in the connected state. Confirmation means, engine rotation speed detection means for confirming that the engine rotation speed has fallen below a predetermined determination rotation speed at which engine stall may occur, and confirmation that the vehicle speed is equal to or higher than a predetermined determination traveling speed Vehicle speed detecting means for preventing the engine stall when the electronic control unit (CPU) detects that the engine speed has fallen below a predetermined judgment speed at which the engine stall may occur. To maintain the engine speed above a predetermined target speed for If an electronically controlled throttle device that controls the electronically controlled throttle device with a signal giving a value and maintains the engine rotational speed at a predetermined target rotational speed or more for avoiding engine stall, it is only necessary to install it in the engine system. The throttle electronic control method for reliably preventing the engine stall can be reliably implemented.

  According to the present invention, the throttle is controlled so that the engine rotation speed is maintained at a predetermined target rotation speed or higher in a predetermined state in which engine stall is likely to occur. It becomes possible to avoid the engine operation state.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  The hardware configuration of the electronically controlled throttle device of the present embodiment is almost the same as that of the conventional one shown in FIG. 4, and an actuator for opening and closing the throttle 3 provided in the intake pipe of the throttle body 2 to the target opening position. 7. Based on the accelerator opening data output from the accelerator opening sensor 8 attached to the accelerator 9 and the throttle opening data from the throttle opening sensor 14, an electronic control unit 10B that sends a required drive signal to the actuator 7 is provided. In particular, as shown in the schematic layout diagram of FIG. 1, the electronic control unit 10A provided in the electronically controlled throttle device 1A has an engine speed sensor 11 and a sensor for detecting that the transmission is in the shift position. A neutral switch 12 and a vehicle speed sensor 13 are connected.

  The electronic control unit 10A mainly executes the throttle electronic control method described in detail below. The electronic control unit 10A is used to execute the following throttle electronic control method in the storage means of the electronic control unit that performs normal throttle control. It can be obtained by adding and storing programs. Note that the electronic control unit 10A may be provided exclusively for the electronic control throttle device, and electronic control means for performing other controls in the engine system may also function.

  Next, the operation of the electronic control unit 10A according to the present embodiment will be described with reference to the flowchart of FIG.

  First, it is determined whether or not the neutral switch is ON based on the detection signal of the neutral switch 12 (A1). If it is OFF, the process returns to the beginning. If it is ON, the transmission is in the shift position and the gear is connected. Recognize that it is in a state.

  Next, it is determined whether or not it is equal to or higher than a predetermined determination traveling speed based on a detection signal of the vehicle speed sensor 13 (A2). It is determined whether or not the signal is below a predetermined rotational speed as a value that may cause an engine stall (A3).

  If it is not lower than the determined rotational speed, the process returns to the beginning, and if it is lower, control of the throttle opening is executed so that the engine rotational speed is maintained at or above a predetermined target rotational speed for avoiding engine stall ( A4).

  At that time, as shown in the relationship diagram between the operating speed and the deviation shown in FIG. 3, the difference between the engine rotational speed and the target rotational speed is calculated to obtain the deviation, and the throttle operation set in advance according to each deviation is obtained. If the throttle 3 is actuated by driving the actuator 7 at a speed, the speed of change of the intake air amount becomes moderate, and the engine speed can be easily controlled. Note that the target rotational speed does not necessarily have to be a value different from the determined rotational speed, and may be the same value by setting both optimal values through experiments or the like.

  As described above, according to the present invention, it is possible to reliably avoid an engine stall caused by a decrease in the engine rotation speed, and it is easy to maintain a good engine operating state.

The layout which shows the outline | summary of embodiment in this invention. The flowchart for demonstrating the operation | movement by the electronic control unit of FIG. 3 is a graph showing an optimum relationship between a rotational speed deviation and a throttle operating speed for determining a throttle operating speed in the control of the target rotational speed for avoiding engine stall in the flowchart of FIG. FIG.

Explanation of symbols

1A Electronic control throttle device, 2 Throttle body, 3 Throttle, 7 Actuator, 10A Electronic control unit, 11 Engine speed sensor, 12 Neutral switch, 13 Vehicle speed sensor

Claims (3)

  In a throttle control method in an electronically controlled throttle device that controls opening / closing of a throttle via an actuator based on a control signal calculated by an electronic control unit based on a detection signal from a predetermined detection unit, the predetermined detection unit includes a neutral switch. The engine speed sensor, the vehicle speed sensor, the transmission is in a gear-connected state at the shift position, the vehicle speed is equal to or higher than a predetermined determination travel speed, and the engine rotation speed is likely to cause engine stall. A throttle electronic control method, characterized in that throttle control is performed so that the engine rotational speed is maintained above a predetermined target rotational speed for avoiding engine stall when the rotational speed is lower than the determined rotational speed.   The electronic control means calculates a difference between the detected engine rotational speed and the target rotational speed to obtain a rotational speed deviation, and sets a throttle operating speed preset as an appropriate value according to the amount of the deviation. 2. The throttle electronic control method according to claim 1, wherein the actuator is driven so as to be realized. An electronically controlled throttle device that controls opening and closing of an engine throttle via an actuator by a control signal from an electronic control unit (CPU), and a neutral switch position for confirming that a transmission is in a shift position and a gear is in a connected state Confirmation means, engine rotation speed detection means for confirming that the engine rotation speed has fallen below a predetermined determination rotation speed at which engine stall may occur, and confirmation that the vehicle speed is equal to or higher than a predetermined determination traveling speed Vehicle speed detecting means for preventing the engine stall when the electronic control unit (CPU) detects that the engine speed has fallen below a predetermined judgment speed at which the engine stall may occur. Maintain engine speed above a predetermined target speed for Positive controls an electronic control throttle device by a signal fed to the electronic control throttle device for maintaining the engine rotational speed above a predetermined target rotational speed for the engine stall avoidance.

Images