JP2017110773A - Control device of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of a vehicle capable of reducing discomfort such as delay in gear change caused by time lag in reduction of input torque by fuel cut in continuous up-shifts.SOLUTION: When up-shifts are continuously executed, a controller 9 measures a first inertia phase interval time Tn-1 from the start of an inertia phase in a prescribed first up-shift to the start of an inertia phase in a second up-shift following the first up-shift, estimates a second inertia phase interval time Tn as an interval between the inertia phases in the up-shifts on and after the second up-shift, and quickens engagement of an engagement device to be engaged in an up-shift following the second up-shift, when the second inertia phase interval time Tn is determined to be the first inertia phase interval time Tn-1 or more.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle control device in which an automatic transmission is connected to an output side of an internal combustion engine.

  In Patent Document 1, in a vehicle having a configuration in which an automatic transmission is connected to the output side of an engine via a fluid transmission device (torque converter), in the case of an upshift that reduces the gear ratio, the inertia phase starts. Prior to or simultaneously with the start of the inertia phase, a control device is disclosed that is configured to perform engine fuel cut and to set the engine compression ratio to be relatively high. In the apparatus of Patent Document 1, when an upshift is completed, a shift shock due to a change in output torque of the engine or a difference in torque between the engine and the automatic transmission can be reduced. Therefore, it is possible to suppress the occurrence of shift shock and shorten the shift time.

  Patent Document 2 discloses an internal combustion engine that is configured to transmit an output torque of an internal combustion engine to driving wheels via an automatic transmission that can change gears by engaging or releasing a clutch. An automatic transmission control device configured to correct the hydraulic pressure applied to the clutch engaged to perform the upshift based on the accelerator operation amount and the engine speed. It is disclosed. In the device of Patent Document 2, the hydraulic pressure acting on the clutch to be engaged becomes a hydraulic pressure suitable for the change in the accelerator opening, so that a shock due to an upshift can be suppressed.

  In Patent Document 3, in a manual transmission type vehicle having a clutch that is engaged or released according to the position of a clutch pedal, if the fuel cut condition is satisfied at the time of a shift, whether the shift is an upshift or not. Accordingly, there is disclosed a control device configured to vary the length of the delay time from the fuel cut command to execution. According to Patent Document 3, the engine speed at the time of shifting can be adjusted quickly and easily by controlling the delay time at the time of upshifting to be shorter than that at the time of downshifting, thereby realizing quick shifting. It can be done.

JP 2010-1332085 A JP 2009-014135 A JP 2005-163760 A

  The shift stage is changed according to the accelerator opening degree and the vehicle speed. For example, the lower the accelerator opening degree and the higher the vehicle speed, the higher speed stage is set. Therefore, when the accelerator pedal is depressed and the vehicle speed increases greatly, upshifts occur continuously. Since the upshift is a shift that decreases the engine speed while increasing the engine output, as described in Patent Documents 1 to 3, engine torque reduction control by fuel cut is executed. There is. However, there is an unavoidable delay in reducing engine torque due to fuel cut, and the time lag varies. When a delay occurs in the decrease in engine torque due to the fuel cut, the start of the inertia phase that occurs during the upshift process is delayed. Therefore, when the upshift continues as described above, the execution of the subsequent upshift is delayed due to the delay of the inertia phase in the preceding upshift, and the inertia phase of the subsequent upshift is delayed. There is. In such a case, it takes time for the overall shift due to successive upshifts, and the shift responsiveness deteriorates, or although the preceding upshift is completed, the end of the subsequent upshift is delayed. This can make you feel uncomfortable.

  The present invention has been made paying attention to the technical problem described above, and is a vehicle capable of reducing a sense of incongruity such as a shift delay due to a time lag of a reduction in input torque due to a fuel cut during continuous upshifts. An object of the present invention is to provide a control device.

  In order to achieve the above-described object, the present invention provides an automatic transmission in which an upshift is performed in which a gear ratio is reduced stepwise by engaging or releasing an engagement device, and an input shaft of the automatic transmission. In a control apparatus for a vehicle including an internal combustion engine that is connected and stops combustion by fuel cut when the upshift is performed, the controller includes a controller that controls the engine and the automatic transmission, When a plurality of the upshifts are successively executed, the first phase from the start of the inertia phase in the first upshift to the start of the inertia phase in the second upshift subsequent to the first upshift. 1 Inertia phase interval time is measured, and the upshift on the lower gear side among the upshifts after the second upshift. -Predict the second inertia phase interval time that is the sum of the interval from the start of the inertia phase to the fuel cut command output in the upshift on the high speed side and the time lag from when the fuel cut command is output until it is executed And determining that the second inertia phase interval time is equal to or longer than the first inertia phase interval time, and when the determination is satisfied, the engaging device is engaged by an upshift after the second upshift. It is configured to speed up the engagement.

  According to the present invention, when the second inertia phase interval time is equal to or longer than the first inertia phase interval time when the power-on upshift is continuously executed, the upshift after the second upshift is involved. Engage the engaging device to be combined. That is, it is avoided that the interval between the upshifts after the second upshift is longer than the interval between the first upshift and the second upshift. In other words, by suppressing or avoiding the delay of the start of the inertia phase, the interval between the upshift and the upshift is always the same or shortened as the high speed stage. Therefore, the driver can be prevented from feeling uncomfortable or uncomfortable.

It is a flowchart for demonstrating an example of the control in embodiment of this invention. It is a schematic diagram for demonstrating the whole structure of a drive device. It is a figure for comparing and explaining embodiment of this invention and a comparative example. It is a time chart for demonstrating an example of the control in embodiment of this invention compared with the control of a comparative example.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a schematic diagram showing a driving device 1 to which the present invention is applied. As shown in FIG. 2, the drive device 1 includes an engine 2 and an automatic transmission 4 connected via a rotation shaft (input shaft) 3 to which the rotation of the engine 2 is transmitted. The drive torque output from the automatic transmission 4 is transmitted to the differential gear 6 through the output shaft 5 and further transmitted from the differential gear 6 to the left and right drive wheels 8 through the drive shaft 7. ing. The automatic transmission 4 is a transmission that can automatically set a plurality of gear ratios step by step. For example, a clutch or a brake, which is an example of an engagement device, is engaged or released to change the drive torque transmission path and execute a shift. The engine 2 corresponds to the internal combustion engine in the present invention.

  The engine 2 is configured to be able to electrically control fuel supply, ignition timing, or the number of combustion cylinders. An electronic control unit (E-ECU) 9 for performing the control is provided. The E-ECU 9 is configured mainly with a microcomputer, configured to perform calculations using input data or data stored in advance, and output the result of the calculation to the engine 2 as a control command signal. Has been. The E-ECU 9 is connected with a vehicle speed sensor 10, an accelerator opening sensor 11, an engine speed sensor (not shown), and the like, and data such as a vehicle speed, an accelerator opening degree, and an engine speed are shown as data indicating the running state of the vehicle. Input from each sensor to the E-ECU 9. Further, the engine 2 can execute fuel cut by the output from the E-ECU 9. The fuel cut is a cylinder deactivation operation in which combustion in all or some of the cylinders in the engine 2 is deactivated. By executing this fuel cut, the torque output from the engine 2 can be reduced. The shift in the automatic transmission 4 is controlled by the E-ECU 9.

  As described above, the automatic transmission 4 is configured such that a gear position (speed ratio) is set according to a combination of engagement and release of engagement devices such as a clutch and a brake. As an example, the clutch is a hydraulic friction engagement device that is engaged and released by hydraulic pressure and that has a transmission torque capacity corresponding to the hydraulic pressure. FIG. 2 schematically shows a clutch C1 that is engaged at a predetermined low speed side gear stage, and a clutch C2 that is engaged at another speed stage that is higher than the low speed side gear stage. . A torque converter (not shown) connected to the input shaft 3 side of the automatic transmission 4 may have a conventionally known configuration including a pump impeller, a stator, and a turbine runner.

  The clutches C1 and C2 of the automatic transmission 4 are controlled by the hydraulic control unit 12. The hydraulic control unit 12 controls the line pressure by an electrically controlled valve (not shown), supplies and discharges hydraulic pressure to the lockup clutch, the clutch, etc., and sets the transmission torque capacity of the clutch. It is configured to control hydraulic pressure and the like. The hydraulic control unit 12 may have the same configuration as the hydraulic control unit provided in a conventionally known automatic transmission for vehicles.

  An electronic control unit (T-ECU) 13 for controlling the automatic transmission 4 via the hydraulic control unit 12 is provided. The T-ECU 13 is mainly composed of a microcomputer, and is connected to the E-ECU 9 so as to perform data communication. Further, the T-ECU 13 receives data such as vehicle speed and accelerator opening, performs calculations using the input data and data stored in advance, and uses the calculation result as a control command signal as a hydraulic control unit. 12 is configured to output to 12.

  In the case where the upshift determination is established by the increase in the vehicle speed, and the upshift is a shift (clutch-to-clutch shift) in which the clutch C1 is released and the clutch C2 is engaged, the shift control device according to the embodiment of the present invention. Is configured to execute the control described below. An example of the control is shown in a flowchart in FIG. 2, and the control at each step shown here is at the time of a power-on upshift (hereinafter sometimes referred to as an upshift) of clutch-to-clutch shift. Further, it is executed by the aforementioned E-ECU 9 or T-ECU 13 corresponding to the controller of the present invention.

  As shown in step S1 of FIG. 1, first, when the upshift, that is, the power-on upshift is executed in the automatic transmission 4, the process proceeds to step S2. In step S2, it is determined whether or not the power-on upshift is continuously executed. This determination is made based on whether or not the upshift has been performed immediately before the upshift determined in step S1. If the power-on upshift is not continuously executed and if a negative determination is made in step S2, this routine is returned without executing the subsequent control.

  On the other hand, if a positive determination is made in step S2 by continuously executing the power-on upshift, the process proceeds to step S3. When the upshift is executed, the fuel cut of the engine 2 is executed to reduce the torque of the engine 2 and gradually approach the synchronous rotational speed at the high speed stage which is the speed stage after the shift. In fuel cut, an unavoidable time lag occurs between execution of the command and execution. For this reason, in step S3, a time lag that occurs at the time of executing the fuel cut in the second upshift on the high speed stage side among the upshifts that are continuously executed is predicted or calculated. The time lag is calculated when a fuel cut command is output. For example, when a fuel cut command is output, the time lag is calculated immediately after fuel injection is determined in the cylinder to be fuel cut. It is determined by factors such as whether or not there is, or in which state of the combustion cycle (expansion / exhaust / intake / compression) in the engine 2.

  When the time lag in the fuel cut of the second upshift is calculated in step S3, the process proceeds to step S4. In step S4, it is determined whether or not a predetermined formula is established. In the predetermined formula, the interval from the start of the inertia phase to the start of the next inertia phase in the upshift and the turbine rotational speed at the start of the inertia phase are objects of determination. Specifically, it will be described below.

  In step S4, first, an interval between upshifts is calculated. That is, among the upshifts executed continuously, it occurs from the start of the inertia phase that occurs at the first upshift that is executed at the low speed stage side to the second upshift that is executed at the high speed stage side from the first upshift. A first inertia phase interval time (hereinafter referred to as a first interval time) until the start of the inertia phase is calculated or measured (actual measurement). Further, a second inertia phase interval time (hereinafter referred to as a second interval) from the start of the inertia phase generated in the second upshift to the start of the inertia phase generated in the third upshift executed on the higher speed side than the second upshift. Calculated or predicted). The second interval time is estimated by measuring (actually measuring) from the start of the inertia phase in the first upshift to the fuel cut command output in the second upshift, and the fuel cut obtained in step S3 is obtained from this measured value. It is obtained by adding a time lag from command output to execution. The inertia phase referred to here is a period in which the turbine rotation speed (input shaft rotation speed) in the automatic transmission 4 changes from the rotation speed of the transmission gear ratio before the upshift to the rotation speed of the transmission gear ratio after the upshift. is there.

  Next, the turbine speed at the start of the inertia phase of the upshift is calculated. That is, the first turbine rotational speed at the start of the inertia phase in the second upshift is calculated or measured (actual measurement), and the second turbine rotational speed at the start of the inertia phase in the third upshift is calculated or predicted. The The second turbine rotational speed is predicted or calculated based on an increase rate of the turbine rotational speed before and after the fuel cut command is output.

Then, based on each element described above, it is determined whether or not a predetermined formula is established. Specifically, the first turbine speed is nt_n-1 (nt_2), the second turbine speed is nt_n (nt_3), the first required time is Tn-1 (T1), and the second required time is Tn. (T2), and further, it is determined whether or not the following expression holds when the first predetermined value is α and the second predetermined value is β as a predetermined value determined in accordance with the characteristics of the vehicle. .
nt_n ≧ nt_n−1−α (α ≧ 0) (1)
Tn ≧ Tn−1−β (β ≧ 0) (2)

  The predetermined values α and β will be specifically described. As described above, the predetermined values α and β are appropriately determined according to the characteristics of the vehicle. That is, the first predetermined value α is calculated by the expression (1) when it is preferable that the turbine speed at the start of the inertia phase in each upshift is the same when the upshift is continuously executed. Are set so that the left side and the right side of On the other hand, when it is preferable that the turbine speed at the start of the inertia phase is smaller as the upshift at the high speed stage, the turbine speed at the start of the inertia phase is set to the same speed at each upshift. The first predetermined value α is set to be larger than that in the case where it is performed.

  Further, when it is preferable that the second predetermined value β is the same as each interval time including the first interval time and the second interval time when the upshift is continuously executed, the expression (2) is used. Are set so that the left side and the right side of On the other hand, when it is preferable to shorten the interval time as the speed increases, the second predetermined value β is set to a larger value compared to the case where each interval time is set to be the same time. . That is, by adjusting the values of the predetermined values α and β, the interval time and the turbine speed on the high speed side can be managed.

  If neither of the expressions (1) and (2) described above is satisfied, and if a negative determination is made in step S4, this routine is returned without executing the subsequent control. If at least one of the two expressions described above is satisfied, the process proceeds to step S5. When the routine proceeds to step S5, the hydraulic pressure control command for the clutch C2 to be engaged when the upshift on the high speed stage side is executed is changed. Specifically, control is performed so that the expressions (1) and (2) are not satisfied by increasing the timing of engaging the clutch C2. That is, the inertia phase is controlled to be started earlier by early engagement of the clutch C2.

  Next, a difference from the comparative example caused by executing the above-described control will be described with reference to FIG. 3 in which the vertical axis represents the turbine speed and the horizontal axis represents time. As shown in FIG. 3, the second required time T2 in the embodiment of the present invention indicated by the solid line is shorter than the second required time T2 in the comparative example indicated by the broken line. That is, the interval between the upshifts on the high speed stage side is shorter than the interval between the upshifts on the low speed stage side. Further, the second turbine speed nt_2 in the embodiment of the present invention indicated by the solid line is smaller than the second turbine speed nt_2 in the comparative example indicated by the broken line. That is, the inertia phase is started at a smaller rotational speed as the upshift of the high speed stage is compared with the upshift of the low speed stage.

  Next, FIG. 4 shows changes in the hydraulic pressure that is applied to the clutch (engagement side clutch) C2 that occurs in the third upshift that is the highest speed side when the control according to the embodiment of the present invention is executed. I will explain. As shown in FIG. 4, when it is determined to execute the third upshift, first, hydraulic pressure is applied to the clutch C2. The hydraulic pressure to be applied here is such that the clutch C2 does not transmit torque, and is supplied in order to improve the responsiveness when an engagement command is output.

  After the hydraulic pressure acting on the clutch C2 is maintained in such a controlled state, the hydraulic pressure gradually increases and torque is transmitted. Although not shown in FIG. 4, the hydraulic pressure acting on the clutch C <b> 1 released with the third upshift is gradually reduced, and the clutch C <b> 1 is completely released when the fuel cut command is output. The Therefore, the torque at the output shaft 5 of the automatic transmission 4 is reduced. Further, the rotational speed of the input shaft 3 in the automatic transmission 4, that is, the second turbine rotational speed, changes at a constant increase rate due to the torque of the engine 2.

  When the fuel cut command is output, the reduction of the output shaft 5 torque in the automatic transmission 4 stops (time t1). Further, after the fuel cut command is output, the hydraulic pressure applied to the clutch C2 is further increased. The timing for further increasing the hydraulic pressure is a timing determined so that neither of the expressions (1) and (2) holds. Therefore, as shown in FIG. 4, in the embodiment of the present invention indicated by the solid line, the hydraulic pressure applied to the clutch C2 is increased faster than the comparative example indicated by the broken line.

  As the hydraulic pressure increases, the transmission torque capacity of the clutch C2 increases, so the second turbine speed decreases. Therefore, as shown in FIG. 4, the second turbine rotational speed starts to decrease at a smaller value than the turbine rotational speed of the comparative example. That is, the timing for starting the inertia phase of the third upshift is earlier than that of the upshift of the comparative example. Further, as the hydraulic pressure applied to the clutch C2 increases, the torque of the output shaft 5 in the automatic transmission 4 increases. Since this output shaft 5 torque is a small value, there is little possibility that the passenger will feel a shock.

  When the fuel cut is executed, the torque output from the engine 2 is reduced (at time t2). As the torque output from the engine 2 decreases, the second turbine speed decreases, and the torque of the output shaft 5 transmitted via the clutch C2 decreases. The torque cut of the engine 2 is completed by continuing the fuel cut for a predetermined time. In this embodiment, since the second turbine rotational speed becomes a small value as compared with the comparative example due to the early engagement of the clutch C2, the fuel cut execution time is shorter than the execution time in the comparative example. It has become.

  As the fuel cut is completed, the clutch is completely engaged by further increasing the hydraulic pressure. In addition, since fuel is supplied to the engine 2 after the fuel cut is completed, the second turbine speed and the torque of the output shaft 5 gradually increase. That is, the inertia phase ends and the third upshift is completed.

  With this configuration, when the power-on upshift is continuously executed and the second interval time is equal to or longer than the first interval time, the engagement of the clutch C2 to be engaged in the upshift after the second upshift is performed. Make a meeting sooner. That is, it is avoided that the interval between the upshifts after the second upshift is longer than the interval between the first upshift and the second upshift. In other words, by suppressing or avoiding the delay of the start of the inertia phase, the interval between the upshift and the upshift is always the same or shortened as the high speed stage. Further, when the second turbine rotational speed is equal to or higher than the first turbine rotational speed, the engagement of the clutch C2 to be engaged in the upshift after the second upshift is made faster. That is, it is avoided that the second turbine rotation speed becomes equal to or higher than the first turbine rotation speed. In other words, the turbine rotational speed at the start of the inertia phase is always the same or configured to be smaller as the speed increases. Therefore, the driver can be prevented from feeling uncomfortable or uncomfortable.

  The preferred examples of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to the above-described configuration. That is, the above-described configuration is merely an example for facilitating understanding of the invention, and does not limit the invention unless otherwise specified. Various modifications and changes can be made within the scope of the gist of the invention described in the claims. For example, it may be configured to compare only the turbine speed at the start of the inertia phase of each upshift. That is, in the vehicle configured as described above, the controller that controls the engine 2 and the automatic transmission 4 is configured so that when the upshift is continuously performed, the rotational speed of the turbine runner at the start of the inertia phase of the upshift. Measure or predict the turbine rotation speed and measure the first turbine rotation speed in the low speed stage upshift executed on the low speed stage side among the continuous upshifts, and execute it on the high speed stage side from the low speed stage upshift. The second turbine rotation speed in the high-speed upshift is determined, and it is determined that the second turbine rotation speed is equal to or higher than the first turbine rotation speed. The clutch C2 to be engaged may be fastened.

  DESCRIPTION OF SYMBOLS 1 ... Drive apparatus, 2 ... Engine, 3 ... Input shaft, 4 ... Automatic transmission, 5 ... Output shaft, 9 ... E-ECU, 13 ... T-ECU

Claims (1)

An automatic transmission in which an upshift is executed to reduce the gear ratio stepwise by engaging or disengaging an engagement device; and when the upshift is executed when connected to the input shaft of the automatic transmission In a control apparatus for a vehicle including an internal combustion engine that stops combustion by fuel cut,
A controller for controlling the engine and the automatic transmission;
The controller is
When a plurality of the upshifts are successively executed, the first phase from the start of the inertia phase in the first upshift to the start of the inertia phase in the second upshift subsequent to the first upshift. Measure the inertia phase interval time,
Of the upshifts after the second upshift, the interval from the start of the inertia phase of the upshift on the low gear stage side to the fuel cut command output in the upshift on the high speed stage side, and the fuel cut command are output. Predicting the second inertia phase interval time, which is the sum of the time lag from execution to execution,
Determining that the second inertia phase interval time is equal to or greater than the first inertia phase interval time;
A vehicle control device configured to speed up engagement of an engagement device to be engaged in an upshift after the second upshift when the determination is established.

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