JP5169932B2 - Coasting control device - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a coasting control device in which coasting control is accurately, smoothly, and comfortably performed.

  In the vehicle, when the accelerator pedal is depressed when the clutch is disengaged, the accelerator is opened and the engine is so-called empty, and the engine speed settles at the engine speed corresponding to the accelerator opening. At this time, the driving force generated by the engine and the engine internal resistance (friction) are balanced, and the engine output torque is zero. That is, the engine does not work at all with respect to the outside, and fuel is wasted. For example, if the engine speed is 2000 rpm, the driver can hear a loud engine sound, so that a considerable amount of fuel is consumed wastefully.

  The state in which the engine does not work to the outside is not limited to the idling when the clutch is disengaged, but also occurs while the vehicle is running. That is, the engine only rotates at an engine speed corresponding to the accelerator opening, as in the case of flying, and does not contribute to acceleration / deceleration of the vehicle. At this time, fuel is consumed only for rotating the engine, which is very wasteful.

  The present applicant has proposed a coasting control device that performs coasting control that reduces fuel consumption by disengaging the clutch and returning the engine to an idle state when the engine is rotating but does not work to the outside ( Patent Document 2).

JP-A-8-67175 JP 2006-342832 A

  However, in the coasting control of Patent Document 2, the clutch may be disengaged even when the driver depresses the accelerator with the intention of acceleration, and the driver feels torque loss when shifting from deceleration to acceleration. Is uncomfortable.

  Therefore, the present applicant has created a coasting control determination map using the accelerator opening and the clutch rotational speed as indices, and the coasting point where the coordinate points of the accelerator opening and the clutch rotational speed are preset on the coasting control determination map. A coasting control device is being proposed that starts coasting control when the control threshold line passes in the direction in which the accelerator opening decreases.

  By the way, since the accelerator opening is an analog signal in which the stroke of the accelerator pedal is detected by a sensor, the accelerator opening is not always a smooth change that continues to decrease or increase over the long term. Factors also affect, including a small repetition of decrease and increase. Therefore, when coasting control is started / finished by the decrease or increase of the analog signal of the accelerator opening as a trigger, coasting control is delayed or not started, hunting occurs, or a state different from the driver's will In this case, coasting control may start or end.

  Accordingly, an object of the present invention is to provide a coasting control device that solves the above-described problems and allows coasting control to be started / finished accurately, smoothly, and comfortably.

  In order to achieve the above object, the present invention comprises an accelerator opening detector that digitally samples an output signal of an accelerator opening sensor every predetermined time, and sets the moving average value as an accelerator opening every predetermined time; When the accelerator opening speed is negative and the absolute value is smaller than the preset starting reference value, the coasting control start determination is made. The determination condition detection unit that permits the engine output, and the engine output torque zero line that is the boundary between the negative region where the engine output torque is negative and the positive region where the engine output torque is positive, using the accelerator opening and the clutch rotational speed as indices. The coasting control determination map in which the coasting control threshold line is set and the coasting control start determination are permitted, and the coasting control determination map is activated on the coasting control determination map. When Le opening and the coordinate point of the clutch rotational speed has passed in the direction of decreasing the accelerator opening the coasting control threshold line, in which a coasting control execution determination unit to initiate coasting control.

  The determination condition detector calculates a short time accelerator opening speed by differentiating a predetermined time less than the predetermined time of the accelerator opening, and the absolute value of the short time accelerator opening speed is preset. When larger than the reference value, the coasting control end determination is permitted, and the coasting control determination map sets a coasting controllable region having a finite width including the coasting control threshold line between the minus region and the plus region. The coasting control execution determination unit is permitted to determine the coasting control end, and when the coordinate point of the accelerator opening and the clutch rotational speed goes out of the coasting controllable region, the coasting control is terminated. Also good.

  The coasting control execution determination unit may start the coasting control only when the clutch rotational speed exceeds the lower limit threshold value.

  The present invention exhibits the following excellent effects.

  (1) Start / end of coasting control is performed accurately, smoothly and comfortably.

It is a figure explaining the calculation of the coasting control apparatus of this invention, (a) is a time waveform figure of accelerator opening, (b)-(d) is a partial figure of the time waveform of accelerator opening. It is the flowchart which showed the procedure for the coasting control apparatus of this invention to perform the calculation demonstrated in FIG.1 (b). It is the flowchart which showed the procedure for the coasting control apparatus of this invention to perform the calculation demonstrated in FIG.1 (c) and FIG.1 (d). 1 is a block configuration diagram of a vehicle clutch system to which a coasting control device of the present invention is applied. It is a block diagram of the actuator which implement | achieves the clutch system of FIG. 1 is an input / output configuration diagram of a vehicle to which a coasting control device of the present invention is applied. It is a block block diagram of the coasting control apparatus of this invention. It is an operation | movement conceptual diagram for demonstrating the outline of coasting control. It is a graph image figure of a coasting control determination map. It is a graph for demonstrating the fuel consumption reduction effect by coasting control. It is a figure of the coasting control determination map in which coasting control was actually performed. It is a figure explaining the calculation of the coasting control apparatus which this applicant is proposing, (a) is a time waveform figure of accelerator opening, (b) is a coasting control determination map, (c), (d) is accelerator opening It is a partial figure of a time waveform of degree. It is a figure explaining the effect of this invention, (a) is a graph of the accelerator opening degree sampled digitally, (b) is a graph of the difference for every 1 sample, (c) is a graph of the difference for every 10 samples. .

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  The coasting control apparatus according to the present invention differentiates the accelerator opening by using a moving average value of the output signal of the accelerator opening sensor as an accelerator opening, and a relatively long predetermined time of the accelerator opening to obtain an accelerator opening speed (hereinafter, When the long-time accelerator opening speed is negative and the absolute value is smaller than the preset start reference value, the coasting control start determination is permitted. When the accelerator opening speed is calculated by differentiating the accelerator opening for a relatively short period of time and the absolute value of the short-time accelerator opening speed is greater than the preset end reference value, coasting control ends. It is characterized in that the determination is allowed.

  As shown in FIG. 1A, the time waveform 11 of the accelerator opening obtained as a moving average value of the output signal of the accelerator opening sensor is a relatively smooth waveform that does not include small repetitions of decrease and increase. Become. A vertical broken line indicates a time interval for each sampling period Δt.

  In the illustrated time waveform 11 (accelerator opening which is a moving average value), the state where the accelerator opening is maximized will be described. At first, the accelerator opening gradually decreases (within the circle A1) and then decreases rapidly. However (in circle A2), it is almost zero. The accelerator opening, which is the moving average value, is differentiated using two types of time units. That is, as a differentiation in a long time unit, the accelerator opening is differentiated over a long predetermined time (for example, 1000 ms). As a differentiation in a short time unit, the accelerator opening is differentiated over a short predetermined time (for example, 100 ms).

  As shown in FIG. 1 (b), a start reference in which the long-time accelerator opening speed obtained by differentiating a predetermined time with a long accelerator opening is negative and the absolute value thereof is set in advance. When the slope is lower than the value, that is, when the slope is lower to the right and the slope becomes gentler than a threshold value (not shown) for a slope over a predetermined sampling period (9 sampling periods in the figure) on the graph, lameness Allow control start judgment.

  As shown in FIG. 1 (c), the short-term accelerator opening speed obtained by differentiating a predetermined time with a short accelerator opening is negative, and its absolute value is set in advance. When the slope is larger than the value, that is, when the slope is lower to the right and the slope becomes tighter than the threshold (not shown) for a slope over a predetermined sampling period (one sampling period in the figure) on the graph, lameness Allow control termination judgment.

  As shown in FIG. 1 (d), the short-time accelerator opening speed obtained by differentiating a relatively short period of time of the accelerator opening is positive and the absolute value thereof is preset. When the slope is larger than the end reference value, that is, when the slope over the predetermined sampling period (one sampling period in the figure) on the graph rises to the right and the slope becomes tighter than the threshold (not shown). Allow the determination of coasting control end.

As described above, the coasting control device according to the present invention is
(1) The digital sampling data of the output signal of the accelerator opening sensor is not directly used as the accelerator opening, but the moving average value is calculated at a predetermined time interval for the digital sampling data, and the moving average value is set as the accelerator opening.

    (2) The accelerator opening obtained by the moving average calculation is differentiated between a relatively long predetermined time and a relatively short predetermined time to obtain two types of accelerator opening speeds.

    (3) When the accelerator opening speed for a long time is smaller than the start reference value, the coasting control start determination is permitted.

(4) When the accelerator opening speed for a short time is larger than the end reference value, the end of coasting control is permitted.
The control is performed.

  The condition detection described with reference to FIG. 1 is realized by the procedures of FIGS.

  As shown in FIG. 2, the procedure for shifting to coasting control start determination includes step S21 for determining whether coasting control is being performed, step S22 for calculating a long-time accelerator opening speed when coasting control is not being performed, Step S23 for determining whether or not the accelerator opening speed is smaller than the start reference value (sign is negative and the absolute value is smaller than the start reference value). It has step S24 which transfers.

  When the long-time accelerator opening speed is not smaller than the start reference value by the procedure of FIG. 2, the coasting control start map is not determined by the coasting control determination map described later, and the long-time accelerator opening speed is determined to be the start reference value. The coasting control start determination is valid only when it becomes smaller.

  As shown in FIG. 3, the procedure for shifting to coasting control end determination includes step S31 for determining whether coasting control is being performed, step S32 for calculating a short time accelerator opening speed when coasting control is being performed, and short time In step S33, it is determined whether or not the accelerator opening speed is greater than the end reference value (the absolute value is greater than the end reference value regardless of the sign). It has step S34 which transfers.

  According to the procedure of FIG. 3, when the short-time accelerator opening speed is not larger than the end reference value, the coasting control end map is not determined by the coasting control determination map, and the short-time accelerator opening speed is larger than the end reference value. The coasting control end determination is valid only when

  Hereinafter, a vehicle equipped with the coasting control device of the present invention will be described.

  As shown in FIG. 4, the vehicle clutch system 41 is a system in which a manual type and an automatic type by ECU control are compatible. A clutch master cylinder 43 mechanically connected to the clutch pedal 42 supplies operating oil to the clutch-free operating cylinder 44. On the other hand, a clutch free actuator unit 45 controlled by an ECU (not shown) also supplies operating oil to the clutch free operating cylinder 44. The clutch free operating cylinder 44 supplies hydraulic oil to the clutch slave cylinder 46. The piston 47 of the clutch slave cylinder 46 is mechanically connected to the movable part of the clutch 48.

  As shown in FIG. 5, the clutch-free actuator 55 includes an intermediate cylinder 51 that is the clutch-free operating cylinder 44 of FIG. 4, a solenoid valve 52 that constitutes the clutch-free actuator unit 45, a relief valve 53, and a hydraulic pump 54. In the intermediate cylinder 51, a primary piston 56 and a secondary piston 57 are arranged in series, and when the primary piston 56 is stroked by the operating oil from the clutch master cylinder 43, the secondary piston 57 is accompanied and strokes. . Further, the secondary piston 57 is stroked by the operating oil from the clutch-free actuator unit 45. Operating oil is supplied to the clutch slave cylinder 46 in accordance with the stroke of the secondary piston 57. With this configuration, when manual operation is performed, clutch disengagement / engagement is preferentially performed according to manual operation, and when manual operation is not performed, clutch disengagement / engagement according to ECU control is performed.

  The coasting control device of the present invention can also be applied to an automatic clutch system without a manual type.

  As shown in FIG. 6, the vehicle is provided with an ECU 61 that mainly controls a transmission and a clutch, and an ECM 62 that mainly controls an engine. The ECU 61 includes a shift knob switch, a transmission shift sensor, a select sensor, a neutral switch, a T / M rotation sensor, a vehicle speed sensor, an idle switch, a manual changeover switch, a parking brake switch, a door switch, a brake switch, a half-clutch adjustment switch, Each input signal line of the clutch sensor and the hydraulic switch is connected. The ECU 61 is connected with output signal lines of a motor of a hydraulic pump 54 of the clutch system 41, a solenoid valve, a slope start assisting valve, and a warning & meter. Although not shown, various input signal lines and output signal lines used for engine control are connected to the ECM 62. The ECM 62 can transmit each signal of the engine speed, the accelerator opening, and the engine rotation change request to the ECU 61 via a CAN (Controller Area Network) transmission path. The clutch rotational speed used in the present invention is the rotational speed on the driven side of the clutch, and is the same as the rotational speed of the input shaft of the transmission. Therefore, a clutch rotational speed sensor (not shown) detects the clutch rotational speed from the input shaft.

  As shown in FIG. 7, the coasting control device 71 according to the present invention digitally samples the output signal of the accelerator opening sensor every predetermined time, and sets the moving average value as the accelerator opening for every predetermined time. The degree detector 72 calculates the accelerator opening speed by differentiating a predetermined time of the accelerator opening, the accelerator opening speed is negative, and the absolute value is based on a preset reference value. When it is small, a determination condition detection unit 73 that permits the determination of coasting control start, and a negative region in which the engine output torque is negative and a positive region in which the engine output torque is positive, using the accelerator opening and the clutch rotational speed as indexes. The coasting control determination map 74 in which the coasting control threshold line is set along the engine output torque zero line as the boundary, and the coasting control start determination are permitted, On the coasting control determination map 74, the coasting control execution determining unit 75 starts coasting control when the coordinate point of the accelerator opening and the clutch rotational speed passes the coasting control threshold line in the direction in which the accelerator opening decreases. With.

  The determination condition detecting unit 73 calculates a short time accelerator opening speed by differentiating a predetermined time less than the predetermined time of the accelerator opening, and the absolute value of the short time accelerator opening speed is preset. When larger than the reference value, the coasting control end determination is permitted.

  In the coasting control determination map 74, a coasting controllable region having a finite width including the coasting control threshold line is set between the minus region and the plus region, and the coasting control execution determination unit determines whether the coasting control is completed. Is permitted, and coasting control is terminated when the coordinate point of the accelerator opening and the clutch rotational speed goes out of the coasting controllable region.

  The coasting control execution determination unit 75 starts the coasting control only when the clutch rotational speed exceeds the lower limit threshold value.

  The accelerator opening detection unit 72, the determination condition detection unit 73, the coasting control determination map 74, and the coasting control execution determination unit 75 constituting the coasting control device 71 are preferably mounted on the ECU 61, for example.

  Hereinafter, the operation of the coasting control device 71 of the present invention will be described.

  The operation concept of coasting control will be described with reference to FIG. The horizontal axis shows time and control flow, and the vertical axis shows engine speed. While the accelerator pedal 81 is largely depressed and the accelerator opening degree continues to be 70%, the engine speed 82 increases and the vehicle is accelerated. Assume that the coasting control start condition described later is satisfied when the engine speed 82 is stabilized, the depression of the accelerator pedal 81 is reduced, and the accelerator opening is 35%. By starting the coasting control, the clutch is controlled to be disengaged, and the engine speed 82 is controlled to the idle speed. Thereafter, it is assumed that the accelerator pedal is no longer depressed and the accelerator opening becomes 0% or other coasting control end conditions are satisfied. When the coasting control ends, the engine is controlled to rotate and the clutch is controlled to contact. In this example, since the accelerator opening is 0%, the engine is braked and the vehicle is decelerated.

  If coasting control is not performed, the engine speed remains high as indicated by the broken line during the coasting control execution period, so that fuel is wasted, but coasting control is performed. Thus, the engine speed 82 becomes the idle speed and fuel is saved.

  FIG. 9 shows the coasting control determination map 74 as a graph image.

  The coasting control determination map 74 is created by measuring in advance the correlation between the accelerator opening and the clutch rotational speed for the engine 2 in a clutch disengaged state.

  As shown in FIG. 9, the coasting control determination map 74 is a map in which the horizontal axis is the accelerator opening and the vertical axis is the clutch rotational speed. The coasting control determination map 74 can be divided into a minus region M where the engine output torque is negative and a plus region P where the engine output torque is positive. That is, the minus region M is a region where the engine friction is larger than the engine required torque and the engine output torque is negative. The positive region P is a region where the engine output torque is positive because the engine required torque is larger than the engine friction. The engine output torque zero line Z that is the boundary between the minus region M and the plus region P indicates that the engine does not work to the outside as described in the background art, and fuel is wasted.

  In the present embodiment, the coasting control threshold line T is set slightly to the left of the engine output torque zero line Z of the coasting control determination map 74 (on the side where the accelerator opening is small).

  In the coasting control determination map 74, a coasting controllable area CA having a finite width including the coasting control threshold line T is set between the minus area M and the plus area P.

  In the coasting control determination map 74, a lower limit threshold line U of the clutch rotational speed is set. The lower limit threshold line U defines the lower limit threshold value of the clutch rotational speed regardless of the accelerator opening. The lower limit threshold line U is set slightly higher than the clutch rotational speed in the idle state as shown in the figure.

  The coasting control device 71 is configured to start coasting control when all the following four coasting start conditions are satisfied.

(1) The accelerator pedal operating speed is within the threshold range. (2) The coasting control determination map 74 passes the coasting control threshold line T in the accelerator return direction. (3) The plot point on the coasting control determination map 74 is coasting control. Within the possible area CA (4) In the coasting control determination map 74, the engine speed is not less than the lower limit threshold line U. The coasting control device 71 ends coasting control when at least one of the following two coasting termination conditions is satisfied. It has become.

(1) The accelerator pedal operating speed is outside the threshold range. (2) The plot point on the coasting control determination map 74 is outside the coasting controllable area CA. The coasting start condition (1) indicates that the accelerator opening speed is negative for a long time. And its absolute value is smaller than the starting reference value. The coasting termination condition (1) means that the absolute value of the short-time accelerator opening speed is larger than the termination reference value.

  Next, the operation of the coasting control device 71 will be described in the case where the moving average value, the long-time accelerator opening speed, and the short-time accelerator opening speed, which are features of the present invention, are not used.

  The coasting control execution determination unit 75 constantly monitors the accelerator opening output by the ECM 62 to the engine and the clutch rotational speed detected by the clutch rotational speed sensor, and displays the accelerator opening on the coasting control determination map 74 of FIG. Plot the coordinates of the clutch speed. Coordinate points move over time. At this time, when the coordinate point exists in the coasting controllable area CA, the coasting control execution determination unit 75 determines whether to start coasting control. When the coordinate point does not exist in the coasting controllable area CA, the coasting control execution determination unit 75 does not determine whether to start coasting control.

  Next, when the coordinate point passes the coasting control threshold line T in the direction in which the accelerator opening decreases, the coasting control execution determination unit 75 starts coasting control. That is, the coasting control device 71 controls the clutch to be disengaged and controls the accelerator opening to 0%. As a result, the clutch is disengaged and the engine is in an idle state.

  As shown in FIG. 9 by the arrow indicating the moving direction of the coordinate point, the direction in which the accelerator opening decreases is the left direction in the figure. Even if the coordinate point passes the coasting control threshold line T, if the moving direction of the coordinate point has a component in the right direction in the figure, the accelerator opening increases, so that the coasting control execution determination unit 75 performs coasting control. Do not start.

  The coasting control execution determination unit 75 always monitors the accelerator opening and the clutch rotational speed even after starting coasting control, and plots the coordinate points of the accelerator opening and the clutch rotational speed on the coasting control determination map 74. When the coordinate point goes out of the coasting controllable area CA, the coasting control execution determination unit 75 ends the coasting control. Thereby, the accelerator opening degree determined by the ECM 62 according to the depression amount detected by the accelerator sensor is given to the engine, and the clutch is engaged.

  With the above operation, when the accelerator pedal is operated to the depression side, coasting control is not started even if the coordinate point of the accelerator opening and the clutch rotational speed passes the coasting control threshold line T, and the accelerator pedal is Since the coasting control is started when the coordinate point passes the coasting control threshold line T only when operated on the return side, the driver does not feel uncomfortable.

  The coasting control execution determination unit 75 does not start coasting control when the coordinate point is below the lower limit threshold line U (the clutch rotational speed is lower than the lower limit threshold). This is because even if the clutch is disengaged when the engine is in an idle state, many effects of suppressing fuel consumption cannot be expected. Therefore, coasting control execution determination unit 75 starts coasting control only when the coordinate point is above the lower limit threshold line U.

  The fuel consumption reduction effect by coasting control will be described with reference to FIG.

  First, it is assumed that coasting control is not performed. The engine speed changes in the range of 1600 to 1700 rpm from about 30 s to about 200 s, and decreases from about 1700 rpm to about 700 rpm (idle speed) between about 200 s and about 260 s. .

  The engine torque increases from about 30 s to about 100 s, but then starts to decrease and continues to decrease to about 150 s. The engine torque is about 0 Nm from about 150 s to about 160 s and increases between about 160 s and about 200 s, but becomes about 0 Nm at about 200 s. As a result, the period during which the engine torque is approximately 0 Nm is from about 150 s to about 160 s (ellipse B1), from about 200 s to about 210 s (ellipse B2), and from about 220 s to about 260 s (ellipse B3). is there.

  The fuel consumption (no vertical axis scale; for convenience, it is arranged so as to overlap with the engine torque) changes from about 50 s to about 200 s almost accompanying the transition of the engine torque. Even if the engine torque is approximately 0 Nm, the fuel consumption is not zero.

  Here, when coasting control is performed, the engine speed is controlled to the idle speed during a period in which the engine torque is approximately 0 Nm. The graph shows a line (thick solid line) of the engine speed during coasting control so as to be separated from a line (solid line) of the engine speed not performing coasting control. The coasting control was executed three times for ellipses B1, B2 and B3. The fuel consumption amount in the period when the coasting control is performed is lower than the fuel consumption amount when the coasting control is not performed, and it is understood that the fuel consumption is saved.

  FIG. 11 shows a coasting control determination map 111 in which coasting control is actually performed. Each point indicates a point of the actually detected accelerator opening and clutch rotational speed. In the coasting control determination map 111, a minus region M, a plus region P, a coasting control threshold line T, and a coasting controllable region CA are set.

  Next, the problem will be considered with reference to FIG.

  As shown in FIG. 12 (a), the coasting control device 71 converts the accelerator pedal depression amount 121, which is an analog signal, into a digital signal every predetermined sampling period Δt (for example, 32 ms), and the accelerator opening (Note; (Accelerator opening not moving average). In the circle C1, as shown by two black dots, the accelerator opening slightly decreases during one sampling period Δt. Further, in the ellipse C2, as shown by two black dots, the accelerator opening greatly decreases during one sampling period Δt.

  Now, assuming that the data change in the circle C1 is a change that satisfies the coasting control start condition as shown by a circle C3 in the coasting control determination map 122 of FIG. 12B, coasting control is started. . On the other hand, if the data change in the ellipse C2 is a change that satisfies the coasting control end condition as indicated by a circle C4 in the coasting control determination map 121 of FIG. 12B, coasting control is terminated.

  Here, as shown in FIG. 12C, when the sampling period Δt is remarkably increased, the accelerator pedal depression amount 121 changes within one sampling period Δt. For example, coasting control starts in a circle C5. The condition is met. However, the coasting control device cannot recognize the establishment of the coasting control start condition until the next sampling. Thus, if sampling is performed too roughly, the start of coasting control may be delayed in time or the establishment of conditions may be overlooked.

  On the other hand, as shown in FIG. 12D, when the sampling period Δt is relatively short with respect to the speed of the time change of the accelerator pedal depression amount 121, the depression amount 121 decreases or increases in a relatively short time. Sometimes, after the coasting control start condition is satisfied (circle C6), the coasting control end condition is satisfied immediately (circle C7), and immediately after that, the coasting control start condition is satisfied (circle C8). As described above, since the sampling is performed very finely, each condition is excessively satisfied and hunting is caused.

The coasting control device 71 of the present invention is described in FIG. 1 in order to solve the problem described in FIG.
(1) The digital sampling data of the output signal of the accelerator opening sensor is not directly used as the accelerator opening, but the moving average value is calculated at a predetermined time interval for the digital sampling data, and the moving average value is set as the accelerator opening.

    (2) The accelerator opening obtained by the moving average calculation is differentiated between a relatively long predetermined time and a relatively short predetermined time to obtain two types of accelerator opening speeds.

    (3) When the accelerator opening speed for a long time is smaller than the start reference value, the coasting control start determination is permitted.

(4) When the accelerator opening speed for a short time is larger than the end reference value, the end of coasting control is permitted.
The control is adopted.

  Thereby, the following effects are obtained.

    (1) By performing the moving average, the noise component of the accelerator opening (due to cab vibration or road surface input) can be removed, and stable coasting control can be started and ended.

    (2) Since the shift to the coasting control start determination and the transition to the coasting control end determination are made based on the accelerator opening speed, it is difficult for the coasting control to be overlooked or delayed.

    (3) Since the calculation time of the accelerator opening speed used for determining the coasting control start condition is different from the calculation time of the accelerator opening speed used for the coasting control end determination condition, hysteresis is provided to satisfy both conditions. And hunting is prevented.

    (4) Since the differential for a long predetermined time is used for determining the condition for starting coasting control, it is possible to prevent the start of unnecessary (or less effective) coasting control.

  The effect of the present invention will be described with reference to FIG.

  As shown in FIG. 13A, the moving average value of the digital sampling data of the output signal of the accelerator opening sensor is read into the ECU 61 as the accelerator opening 131. The accelerator opening 131 gradually increases stepwise as shown in the figure, but the degree of increase of the accelerator opening 131 is moderate. Although the vertical axis is not marked, the increase in the accelerator opening 131 is about 1 in 2 sampling periods.

  As shown in FIG. 13 (b), the accelerator opening 131 is subtracted for each sampling period (the difference between the data of a certain sampling period and the data of the next sampling period is obtained) to obtain the accelerator opening speed 132. As a result, the accelerator opening speed 132 takes a value of 0 or 1. Here, if a threshold value 133 is provided for the accelerator opening speed and an attempt is made to detect the slope of the graph due to a gradual increase (or a gradual decrease) in the accelerator opening, the threshold value 133 must be set to 0 or 1. Absent. Since the threshold value 133 cannot be set to a desired value, the degree of freedom for determining the inclination of the accelerator opening is remarkably limited.

  As shown in FIG. 13 (c), the accelerator opening 131 is obtained by subtracting the accelerator opening 131 every 10 sampling periods (determining the difference between data at a certain sampling period and data after 10 sampling periods). Even if the increase in the accelerator opening 131 is gradual, the accelerator opening speed 134 is a value sufficiently larger than 1. As a result, an accelerator opening speed 134 that is correctly proportional to the actual accelerator opening speed (speed at which the accelerator pedal is operated) is obtained. Further, since the numerical value range in which the threshold value 135 can be set is widened, the threshold value 135 can be set to a desired value.

61 ECU
62 ECM
71 coasting control device 72 accelerator opening detection unit 73 determination condition detection unit 74 coasting control determination map 75 coasting control execution determination unit

Claims (3)

An accelerator position detector that digitally samples the output signal of the accelerator position sensor every predetermined time, and sets the moving average value as the accelerator position for each predetermined time;
Calculate the accelerator opening speed by differentiating the accelerator opening for a predetermined time, and start coasting control when the accelerator opening speed is negative and the absolute value is smaller than the preset start reference value A determination condition detection unit that permits the determination of
The coasting control threshold line is set along the engine output torque zero line that is the boundary between the negative region where the engine output torque is negative and the positive region where the engine output torque is positive, using the accelerator opening and the clutch speed as indices. Coasting control determination map,
When the coasting control start determination is allowed, and the coordinate point of the accelerator opening and the clutch rotational speed passes on the coasting control threshold line in the direction of decreasing the accelerator opening on the coasting control determination map, A coasting control device comprising a coasting control execution determination unit that starts coasting control. The determination condition detector calculates a short time accelerator opening speed by differentiating a predetermined time less than the predetermined time of the accelerator opening, and the absolute value of the short time accelerator opening speed is preset. When larger than the reference value, permit the coasting control end determination,
In the coasting control determination map, a coasting controllable region having a finite width including the coasting control threshold line is set between the minus region and the plus region,
The coasting control execution determination unit is permitted to determine the coasting control end, and terminates coasting control when the coordinate point of the accelerator opening and the clutch rotational speed goes out of the coasting controllable region. The coasting control device according to claim 1.   The coasting control device according to claim 1, wherein the coasting control execution determination unit starts the coasting control only when the clutch rotational speed exceeds a lower limit threshold value.

Images