JP2016033405A - Gear change control device of automatic change gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gear change control device of an automatic change gear which can improve a gear change feeling at multiple gear changes.SOLUTION: In the case where a gear change to a target gear change stage from a current gear change stage is [4→1], and a vehicle speed at the setting of the target gear change stage is within a prescribed vehicle speed range, a command for setting the vehicle speed to [4→3→2→1] is outputted. Therefore, the vehicle speed is increased during gear change control following the command, and in the case where a command of the multiple gear changes to a second speed stage from a first speed stage is outputted, the vehicle speed becomes the gear change of [4→3→2→1→2].SELECTED DRAWING: Figure 6

Description

  The present invention relates to a shift control device for an automatic transmission.

  An automatic transmission mounted on a vehicle is configured by combining, for example, a torque converter to which an output from an engine is input and a transmission gear mechanism that is driven by the output from the torque converter. In the automatic transmission, a command for shifting to an appropriate shift stage is issued according to the vehicle speed and the throttle opening. Then, according to the command, a plurality of friction engagement elements such as a clutch and a brake are selectively engaged and released, and the power transmission path in the transmission gear mechanism is switched, so that the gear position corresponding to the vehicle speed and the throttle opening is changed. The gears are automatically shifted.

  For example, when the accelerator pedal is depressed and the throttle opening is fully opened while the vehicle is traveling at a low speed at the fourth speed, a command for shifting from the fourth speed to the first speed is issued. In this case, after shifting from the fourth gear to the third gear, the second gear is jumped from the third gear to the first gear (jumping gear shift). If the vehicle speed rises during the shift from the third gear to the first gear and a command for shifting from the first gear to the second gear (multiple gear shift) is issued, there will be restrictions on the mechanical configuration of the automatic transmission. After the shift speed is once returned to the third speed, a shift from the third speed to the second speed is executed. Therefore, the shift is “4 → 3 → 1 → 3 → 2”, which gives the driver an uncomfortable feeling due to a change in vehicle acceleration (shift shock).

Japanese Patent No. 4826638

  An object of the present invention is to provide a shift control device for an automatic transmission that can improve the shift feeling during multiple shifts.

  In order to achieve the above object, a shift control device for an automatic transmission according to the present invention includes a vehicle speed and throttle opening (vehicle speed detection means for detecting vehicle speed and throttle opening detection means for detecting throttle opening). A target shift speed setting means for setting a target shift speed according to the speed change, and a downshift in which the shift from the current shift speed to the target shift speed set by the target shift speed setting means is changed to two or more low speeds. In addition, when the vehicle speed at the time when the target shift speed is set is not included in the predetermined vehicle speed range, a shift command for skipping at least one shift speed from the current shift speed to the target shift speed is output. However, if the downshift changes by two or more stages and the vehicle speed at the time when the target shift stage is set is within a predetermined vehicle speed range, the current shift stage changes to the target shift stage. Stage by stage and a shift command output means for outputting a shift command to downshift.

  According to this configuration, when the shift from the current shift stage to the target shift stage set by the target shift stage setting unit is a downshift that changes by two or more stages toward the low speed stage, the time point when the target shift stage is set It is determined whether or not the vehicle speed is included in a predetermined vehicle speed region. When the vehicle speed is not included in the vehicle speed range, a shift command for downshifting by skipping at least one shift stage from the current shift stage to the target shift stage is output.

  On the other hand, when the vehicle speed is within the vehicle speed range, a shift command for downshifting one step at a time from the current shift step to the target shift step is output. Therefore, if the target shift stage is changed to a shift stage that is one step higher during the shift from the shift step that is one step higher than the target shift step, after the shift to the original target shift step is completed, Shifting to a shift stage that is one step higher than the shift stage is performed. As a result, fluctuations in vehicle acceleration during multiple shifts can be suppressed. Therefore, the shift feeling at the time of multiple shifts can be improved.

  For example, when the vehicle is traveling at the fourth speed and the throttle opening (accelerator opening) is fully opened and the target gear is set to the first gear, the target gear is set. If the vehicle speed at the time is within a predetermined vehicle speed range, a command for downshifting from the fourth gear to the first gear by one step, that is, a command to change “4 → 3 → 2 → 1” is issued.

  Therefore, when the target shift speed is changed to the 2nd speed during the shift from the 2nd speed to the 1st speed, the shift from the 1st speed to the 2nd speed is completed after the shift from the 2nd speed to the 1st speed is completed. Shifting to a high gear is performed. In this case, since the shift is “4 → 3 → 2 → 1 → 2”, the change in the acceleration of the vehicle can be suppressed, and the driver can be prevented from feeling uncomfortable due to the change in the acceleration.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress giving a driver | operator the discomfort by the fluctuation | variation of an acceleration at the time of a multiple shift, and can improve the shift feeling at the time of a multiple shift.

1 is a block diagram illustrating a configuration of an automatic transmission system to which a transmission control device according to an embodiment of the present invention is applied. It is a skeleton figure which shows the structure of an automatic transmission. It is an operation | movement table | surface of a clutch, a brake, and a one-way clutch. It is a flowchart which shows the flow of the principal part of a shift command output process. It is a gear shift diagram in the D range. It is a graph which shows the change of the turbine speed at the time of a "4-> 3-> 2-> 1-> 2" gear shift, and the acceleration of a vehicle.

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

  FIG. 1 is a block diagram showing a configuration of an automatic transmission system 1 to which a transmission control device according to an embodiment of the present invention is applied.

  The automatic transmission system 1 includes an automatic transmission 2 and an AT (Automatic Transmission) controller 3 that controls the automatic transmission 2.

  The AT controller 3 includes a CPU, a memory that stores programs and various data, a timer that measures elapsed time, and the like. Detection signals are input to the AT controller 3 from various sensors provided in a vehicle on which the automatic transmission system 1 is mounted. The sensors include a throttle opening sensor 4 that detects the opening of the throttle valve (throttle opening), a rotation speed sensor 5 that detects an output rotation speed that is the output rotation speed of the automatic transmission 2, and an automatic transmission 2 A turbine rotation speed sensor 6 that detects a turbine rotation speed that is an input rotation speed (output rotation speed of the torque converter 20), a shift position sensor 7 that detects a shift position, and the like are included. Note that the vehicle speed is calculated based on the output rotational speed detected by the rotational speed sensor 5.

  The AT controller 3 sets a target shift stage according to the vehicle running state (shift stage, throttle opening, vehicle speed, turbine speed, shift position, etc.), and changes the shift stage of the automatic transmission 2 to the target shift stage. Shift control is performed.

  FIG. 2 is a skeleton diagram showing the configuration of the automatic transmission 2.

  The automatic transmission 2 is a four-speed AT that has four forward speeds and one reverse speed. The automatic transmission 2 includes a torque converter 20, an input shaft 21 to which engine power is transmitted via the torque converter 20, three clutches C1 to C3, two brakes B1 and B2, a one-way clutch F, a Ravigneaux type A planetary gear mechanism 22, an output gear 23, an output shaft 24, and a differential (differential gear) 25 are provided.

  The planetary gear mechanism 22 includes a forward sun gear 31, a rear sun gear 32, a carrier 33, pinion gears 34 and 35, and a ring gear 36.

  The forward sun gear 31 is connected to the input shaft 21 via the clutch C1. Forward sun gear 31 is coupled to transmission case 26 via brake B1.

  The rear sun gear 32 is connected to the input shaft 21 via the clutch C2.

  The carrier 33 is connected to the input shaft 21 via the intermediate shaft 27 and the clutch C3. The carrier 33 is connected to the transmission case 26 via the brake B2 and the one-way clutch F. The one-way clutch F allows only forward rotation of the carrier 33 (rotation in the same direction as the engine output shaft).

  The carrier 33 supports the pinion gears 34 and 35. The pinion gears 34 and 35 have different axial lengths. The pinion gear (long pinion gear) 34 has an axial length longer than that of the pinion gear (short pinion gear) 35. The forward sun gear 31 meshes with the pinion gear 34. The rear sun gear 32 and the pinion gear 34 are meshed with the pinion gear 35.

  The ring gear 36 meshes with the pinion gear 34. The ring gear 36 is coupled to the output gear 23.

  The rotation of the output gear 23 is input to the differential device 25 via the output shaft 24.

  FIG. 3 is an operation table of the clutches C1 to C3, the brakes B1 and B2, and the one-way clutch F.

  In FIG. 3, “◯” indicates that the hydraulic pressure is applied to the clutches C1 to C3 and the brakes B1 and B2 that are friction engagement elements, and the one-way clutch F prevents the carrier 33 from reversing. It shows that it is in a state.

  As understood from this operation table, the shift from the third speed (3rd) to the first speed (1st) during the shift from the third speed (3nd) to the second speed (2nd) is performed by the clutch C3, the brake B1, and the one-way clutch F. Engagement / release of the individual frictional engagement elements will occur simultaneously. For this reason, in the automatic transmission system 1, shifting to the second speed during the shifting from the third speed to the first speed is prohibited.

  FIG. 4 is a flowchart showing the flow of the main part of the shift command output process. FIG. 5 is a shift diagram in the D range.

  The AT controller 3 executes a shift command output process for shift control. FIG. 4 shows a main part of the shift command output process executed when the shift range is the D range.

  In the shift command output process, first, the current throttle opening and vehicle speed are acquired (step S1).

  Next, referring to the shift diagram shown in FIG. 5, a target shift stage is set according to the current shift stage, the throttle opening, and the vehicle speed (step S2).

  The shift diagram defines the throttle opening and the vehicle speed, which are the conditions for shifting at each gear, and is stored in the nonvolatile memory of the AT controller 3 in the form of a map, for example. FIG. 5 shows an upshift diagram from the first gear to the second gear, an upshift diagram from the second gear to the third gear, an upshift diagram from the third gear to the fourth gear, and the fourth gear. A downshift diagram from the third gear to the third gear is shown, and a downshift diagram from the third gear to the second gear and a downshift diagram from the second gear to the first gear are shown.

  When the target shift speed is set, whether the current shift speed is the fourth speed and the target shift speed is the first speed, that is, the shift from the current shift speed to the target shift speed is “4 → 1”. It is determined whether or not it is a shift (step S3).

  When the shift from the current shift speed to the target shift speed is “4 → 1” (YES in step S3), the vehicle speed when the target shift speed is set is within a predetermined vehicle speed range (for example, 20 to 30 km / h). It is determined whether it is within (step S4).

  If the vehicle speed at the time of setting the target gear is within a predetermined vehicle speed range (YES in step S4), a command to downshift from the fourth speed to the first speed by one step, that is, “4 → 3 → A command to shift 2 → 1 ”is output (step S5).

  On the other hand, when the shift from the current shift speed to the target shift speed is “4 → 1”, but the vehicle speed at the time of setting the target shift speed is not included in the predetermined vehicle speed range (NO in step S4). A command for jumping from the fourth speed to the third speed and then jumping from the third speed to the second speed to the first speed, that is, a command to change to “4 → 3 → 1” is output (step S6). .

  When the shift from the current shift speed to the target shift speed is not “4 → 1”, a shift command corresponding to the target shift speed is output, although not shown.

  FIG. 6 is a graph showing changes in turbine speed and vehicle acceleration at the time of “4 → 3 → 2 → 1 → 2” shift.

  As described above, when the shift from the current shift speed to the target shift speed is “4 → 1” and the vehicle speed at the time of setting the target shift speed is within the predetermined vehicle speed range, “4 → 3 A command for shifting to “→ 2 → 1” is output. Therefore, if the vehicle speed increases during the shift control according to the command and a multiple shift command (change of the target shift step) from the first gear to the second gear is issued, “4 → 3 → 2 → 1 → 2 ”shift.

  Thereby, at the time of shifting from the fourth speed to the first speed, the acceleration of the vehicle changes smoothly as shown in FIG. Further, the increase in acceleration at the time of shifting from the first gear to the second gear corresponds to the driver's accelerator operation. Therefore, it is possible to suppress the driver from feeling uncomfortable due to the change in acceleration during multiple shifts, and to improve the shift feeling during multiple shifts.

  As mentioned above, although one Embodiment of this invention was described, this invention can also be implemented with another form.

  For example, the case of shifting from the fourth speed to the first speed has been taken up, but the present invention can be similarly applied to the case of downshift of two or more stages from a high speed other than the fourth speed.

  Further, as the automatic transmission 2, a four-speed AT having four forward speeds and one reverse speed is given as an example. However, the automatic transmission 2 has three speeds having three forward speeds and one reverse speed. An AT may be used, or an AT having five or more forward speeds, such as a 5-speed AT having five forward speeds and one reverse speed.

  In addition, various design changes can be made to the above-described configuration within the scope of the matters described in the claims.

2 Automatic transmission 3 AT controller (shift control device, target shift speed setting means, shift command output means)
4 Throttle opening sensor 5 Rotation speed sensor

Claims (1)

Target gear position setting means for setting a target gear position according to the vehicle speed and the throttle opening;
The shift from the current shift stage to the target shift stage set by the target shift stage setting means is a downshift in which the shift to the low speed stage changes by two or more stages, and the vehicle speed at the time when the target shift stage is set is If not included in the predetermined vehicle speed region, a shift command for downshifting by skipping at least one shift stage from the current shift stage to the target shift stage is output, the downshift is changed by two or more stages, and Shift command output means for outputting a shift command for downshifting one step at a time from the current shift step to the target shift step when the vehicle speed at the time when the target shift step is set is within the predetermined vehicle speed range; Shift control device for automatic transmission.

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