JP2013087836A - Automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic transmission that suppresses the occurrence of a busy shift, and reduces the load of a clutch mechanism and a shift mechanism by reducing the number of gear shifts.SOLUTION: The automatic transmission 1 includes a gear shift control device 80 that operates shift mechanisms 70a-70d, and when a gear shift command is transmitted, executes the gear shift control corresponding to the gear shift command by changing the engagement state of the clutch mechanism 30. When the gear shift command is transmitted, the shift control device 80 calculates a shift time Ps required for gear shift control corresponding to the gear shift command and the next command time Pn from the present time to the transmission of the next gear shift command, and waits for the execution of the gear shift control by a standby time Pw when the shift time Ps is longer than the next command time Pn.

Description

  The present invention relates to an automatic transmission that performs an automatic shift according to a vehicle state.

  The automatic transmission is used as a device that automatically changes the rotational driving force output by a prime mover such as an engine mounted on a vehicle. Then, when the shift command is sent, the automatic transmission operates the shift mechanism and the clutch mechanism to perform shift control according to the shift command. Moreover, as an automatic transmission, for example, Patent Document 1 discloses a dual clutch automatic transmission including a plurality of clutches. This dual-clutch automatic transmission realizes high-speed shift control by switching the engagement state of a plurality of clutches in advance when a shift stage scheduled for shift is established and a shift command is sent. .

  In any automatic transmission, depending on the vehicle state including the operation of the driver, a further shift command may be sent while the shift control according to the shift command is being executed. Then, the automatic transmission performs shift control that shifts to a shift stage that corresponds to the preceding shift command and then shifts to the shift stage that corresponds to the subsequent shift command. As described above, depending on the timing at which the shift command is sent, a busy shift may occur in which the automatic transmission cannot immediately start executing the shift control in response to the shift command.

JP 2004-332840 A

  When a busy shift occurs, it takes a long time to complete the shift to the requested shift stage by a later shift command, and there is a possibility that the driver's acceleration request or the like cannot be immediately responded. Further, when shifting is performed a plurality of times in a short time due to the busy shift, there is a concern that the load on the clutch mechanism and the shift mechanism may increase.

  The present invention has been made in view of the above problems, and provides an automatic transmission capable of suppressing the occurrence of a busy shift, reducing the number of shifts, and reducing the load on the clutch mechanism and the shift mechanism. With the goal.

  In order to solve the above-described problem, according to the first aspect of the present invention, an input shaft rotatably supported by a case, a clutch mechanism that transmits a rotational driving force of a prime mover to the input shaft, and an input shaft A shift mechanism that selectively establishes a plurality of shift speeds for shifting the transmitted rotational driving force, and operates the shift mechanism, and when a shift command is sent, the engagement state of the clutch mechanism is switched to change the shift speed. A shift control device that executes a shift control according to the command, and when the shift command is sent, the shift control device includes a shift time required for the shift control according to the shift command and a current time to the next time. The next command time until the shift command is sent out is calculated, and when the shift time is longer than the next command time, the execution of the shift control is waited for the waiting time.

  According to a second aspect of the present invention, in the first aspect, the shift control device calculates the next command time based on a vehicle speed and a change speed of the accelerator opening when the shift command is sent.

  According to a third aspect of the present invention, in the first or second aspect, the shift control device sets the standby time to be longer than the next command time and shorter than the shift time.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, when the shift command is sent, the shift control device has the shift time longer than the next command time, and When the accelerator opening at the time of transmission of the shift command is smaller than a preset threshold, execution of the shift control is waited.

  According to the first aspect of the present invention, when the shift command is sent, the shift control device compares the calculated shift time and the next command time, and executes the shift control for the standby time if the shift time is long. stand by. This shift time is the time required for the shift control to shift from the current shift speed to the required shift speed, and can be calculated according to the state of the current shift speed, the shift mechanism, and the like. Here, in the automatic transmission, the shift command to be sent is determined based on map data having a plurality of shift lines representing the relationship between the vehicle speed and the accelerator opening, for example. Depending on the state of the vehicle, a shift command may be further transmitted based on the map data during a shift to the required shift speed based on the shift command, resulting in a busy shift.

  Therefore, in the present invention, when the shift time is longer than the next command time, that is, when the occurrence of a busy shift is assumed, the execution of the shift control is waited for the standby time. As a result, when a shift command is sent during the standby time as expected, the shift control device can immediately start executing shift control according to the newly sent shift command. Then, it is possible to shift to the final required shift stage by one shift control with respect to the shift command sent over a plurality of times. Therefore, the occurrence of busy shift can be suppressed, and the number of shifts can be reduced to reduce the load on the clutch mechanism and shift mechanism.

  According to the invention of claim 2, the shift control device calculates the next command time based on the vehicle speed and the change rate of the accelerator opening when the shift command is sent. Since the timing for sending the next shift command varies based on the vehicle state and map data, it is possible to estimate the time when the command is sent from the vehicle speed and the changing speed of the accelerator opening. As a result, the next command time from the present to the next shift command being sent can be calculated with high accuracy. Therefore, the shift control device can more reliably determine whether or not standby control for waiting for execution of the shift control is necessary.

  According to the invention of claim 3, the shift control device sets the standby time to be equal to or longer than the next command time and equal to or shorter than the shift time. Thereby, it is possible to suitably set a standby time for waiting for execution of the shift control. Here, it is assumed that the vehicle state changes while waiting for execution of the shift control for the standby time, and that no further shift command is sent within the standby time. Even in such a case, by suitably setting the standby time, it is possible to promptly shift to the shift control based on the currently transmitted shift command. Therefore, the time loss due to waiting for the waiting time can be reduced.

  According to the fourth aspect of the invention, the shift control device is provided on the condition that, in addition to the shift time being longer than the next command time, the accelerator opening at the time of transmission of the shift command is smaller than a preset threshold value. The standby control for waiting for execution of the shift control is executed. The standby control by the shift control device is executed assuming that the next shift command is sent within the standby time. The next shift command is sent in accordance with the vehicle state based on the map data. However, particularly when the accelerator is stepped on, the accelerator opening increases and is easily sent within a short time. On the other hand, if the accelerator opening is greater than or equal to a predetermined value, in order to respond to the driver's acceleration request, control is often performed so that the engine speed is increased at the current shift stage without performing a shift, and the accelerator pedal is further depressed. Since the increase cannot be expected, it is difficult to send the next shift command. Therefore, with the above configuration, it is possible to more reliably determine whether or not standby control is necessary.

It is a skeleton figure which shows the whole structure of the transmission 1 in embodiment. FIG. 4 is a diagram showing shift map data of the transmission 1. 5 is a time chart showing a shift command and a shift state in down shift control. It is a flowchart which shows down shift control including standby control.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying an automatic transmission according to the present invention will be described below with reference to the drawings.

<Embodiment>
(Configuration of transmission 1)
The configuration of the transmission 1 in the present embodiment will be described with reference to FIG. The transmission 1 is a dual clutch type automatic transmission mounted on a vehicle. The transmission 1 includes a first input shaft 11, a second input shaft 12, a first auxiliary shaft 21, a second auxiliary shaft 22 that are rotatably supported by a case (not shown), and a rotational driving force of the engine 2. The dual clutch 30 that transmits the rotation to the rotation shaft, the plurality of transmission gears 41 to 46, 51 to 56, and 61 to 64 that are supported rotatably on the rotation shaft and constitute forward or reverse shift stages, and odd shift stages are selected. The first shift mechanisms 70a and 70c to be established automatically, the second shift mechanisms 70b and 70d to selectively establish even-numbered gears, a shift control device 80, and various sensors 91 and 92 are provided. The above case supports each shaft by a plurality of bearings and contains lubricating oil to be supplied to the plurality of gears and sliding portions included in the first and second shift mechanisms 70a to 70d.

  The engine 2 is a prime mover mounted as a vehicle drive source. The operation of the engine 2 is controlled by an ECU (Engine Control Unit) 3. The ECU 3 acquires various information from a shift control device 80 described later and vehicle information from various sensors 91 and 92. The ECU 3 controls the rotational speed of the engine 2 by adjusting the throttle opening and the fuel injection amount based on the vehicle information. The vehicle speed sensor 91 detects the speed of the vehicle from the rotational speed of the drive wheel and the outer diameter of the drive wheel. The accelerator opening sensor 92 is a sensor that detects an accelerator opening that adjusts the output of the engine 2 in accordance with a driver's accelerator operation or the like.

  The first input shaft 11 is a rotating shaft that is formed in a hollow shaft shape and is rotatably supported with respect to the case by a bearing. Further, a portion for supporting the bearing and a plurality of external splines are formed on the outer peripheral surface of the first input shaft 11. The first input shaft 11 is directly formed with a first speed drive gear 41 and a large-diameter fifth speed drive gear 45. An external spline is formed on the outer peripheral surface of the first input shaft 11, and a three-speed drive gear 43 is press-fitted into the external spline by spline fitting. Further, the first input shaft 11 is formed with a connecting shaft portion that is connected to the first clutch 31 of the dual clutch 30. Thus, the first input shaft 11 is fixedly provided with the drive gears 41, 43, 45 constituting a plurality of odd-numbered speed stages.

  The second input shaft 12 is formed in a hollow shaft shape, is rotatably supported on a part of the outer periphery of the first input shaft 11 via a plurality of bearings, and is rotatable with respect to the clutch housing of the case by the bearings. It is a rotating shaft supported by The second input shaft 12 is disposed concentrically with the first input shaft 11 so as to be relatively rotatable. Similarly to the first input shaft 11, a portion for supporting the bearing and a plurality of external gears are formed on the outer peripheral surface of the second input shaft 12. The second input shaft 12 is formed with a two-speed drive gear 42 and a large-diameter four-speed drive gear 44 (six-speed drive gear 46). The four-speed drive gear 44 is a gear that meshes with the four-speed driven gear 54 and the sixth-speed driven gear 56 and is used as a drive-side gear that constitutes the fourth speed stage and the sixth speed stage. Further, the second input shaft 12 is formed with a connecting shaft portion that is connected to the second clutch 32 of the dual clutch 30. Thus, the second input shaft 12 is fixedly provided with the drive gears 42, 44, and 46 constituting a plurality of even-numbered speed stages.

  The first countershaft 21 is a rotating shaft that is disposed in parallel to the first input shaft 11 inside the case and is rotatably supported by the bearing with respect to the case. A final reduction gear 61 and a plurality of external splines are formed on the outer peripheral surface of the first countershaft 21. Hubs 71 of a first shift mechanism 70a and a second shift mechanism 70b described later are press-fitted into the external splines of the first countershaft 21 by spline fitting. The final reduction gear 61 is meshed with a ring gear 64 of a differential (differential mechanism). Further, the first countershaft 21 is formed with a support portion that supports the first-speed driven gear 51, the third-speed driven gear 53, the fourth-speed driven gear 54, and the reverse gear 63 so as to be freely rotatable.

  The second countershaft 22 is a rotating shaft that is arranged in parallel with the first input shaft 11 inside the case and is rotatably supported by the bearing with respect to the case. Further, similarly to the first countershaft 21, a final reduction gear 62 and a plurality of external splines are formed on the outer peripheral surface of the second countershaft 22. A hub 71 of a first shift mechanism 70c and a second shift mechanism 70d, which will be described later, and a parking gear 65 of a parking mechanism (not shown) are press-fitted into the external spline of the second countershaft 22 by spline fitting. The parking mechanism is a mechanism that maintains the stationary state of the vehicle by preventing the rotation of the shaft connected to the drive wheels by restricting the rotation of the parking gear 65 when the vehicle is stopped. . The final reduction gear 62 meshes with a differential ring gear 64. Further, the second countershaft 22 is formed with a support portion that supports the second-speed driven gear 52, the fifth-speed driven gear 55, and the sixth-speed driven gear 56 so as to be freely rotatable.

  The dual clutch 30 is a clutch mechanism having a first clutch 31 that transmits the rotational driving force of the engine 2 to the first input shaft 11 and a second clutch 32 that transmits the rotational driving force of the engine 2 to the second input shaft 12. is there. The dual clutch 30 is accommodated in the clutch housing of the case, and is provided concentrically with the first input shaft 11 and the second input shaft 12. The first clutch 31 is connected to the connecting shaft portion of the first input shaft 11, and the second clutch 32 is connected to the connecting shaft portion of the second input shaft 12. The dual clutch 30 operates an actuator (not shown) based on a control command input from the transmission control device 80. The actuator can adjust the engagement force of the first clutch 31 and the second clutch 32 according to the amount of operation. The dual clutch 30 having such a configuration switches the engagement state of the first clutch 31 and the second clutch 32 under the control of the transmission control device 80.

  The reverse gear 63 is provided on the support portion of the reverse gear formed on the first countershaft 21 so as to be free-wheeling. Further, in the present embodiment, the reverse gear 63 is always meshed and rotationally connected to a small-diameter gear 52 a formed integrally with the second-speed driven gear 52. The ring gear 64 is meshed with the final reduction gear 61 and the final reduction gear 62 so as to be always rotationally connected to the first auxiliary shaft 21 and the second auxiliary shaft 22. The ring gear 64 constitutes a differential mechanism as a final gear in the transmission 1, and is connected to drive wheels via a drive shaft.

  The first and second shift mechanisms 70a to 70d are mechanisms that are controlled by the shift control device 80 to establish a shift stage according to the shift operation. In the present embodiment, the transmission 1 has first and second shift mechanisms 70a to 70d arranged at four locations, as shown in FIG. The first and second shift mechanisms 70a to 70d are different in the target of the transmission gear connected to the first countershaft 21 or the second countershaft 22 among the transmission gears. In the first shift mechanism 70a, the first-speed driven gear 51 constituting the first speed and the third-speed driven gear 53 constituting the third speed among the odd-numbered speeds are connected. In the second shift mechanism 70b, the fourth-speed driven gear 54 and the reverse gear 63 constituting the fourth speed among the even-numbered speeds are to be connected. In the first shift mechanism 70c, only the fifth-speed driven gear 55 constituting the fifth speed among the odd-numbered speeds is to be connected. In the second shift mechanism 70d, the second-speed driven gear 52 constituting the second speed and the sixth-speed driven gear 56 constituting the sixth speed among the even-numbered speeds are connected.

  The first and second shift mechanisms 70 a to 70 d include a hub 71 and a sleeve 72. The hub 71 has a hollow disk shape in which an internal spline and an external spline are formed. The hub 71 is a member that is press-fitted into the external spline of the first countershaft 21 or the second countershaft 22 by spline fitting and rotates integrally with the press-fitted subshaft. The sleeve 72 meshes with the external spline of the hub 71 so as to be movable in the axial direction with respect to the hub 71. The sleeve 72 is slidable in the axial direction of the rotary shaft and can be engaged with the driven gears 51 to 56 of the shift stage or the piece gear portion of the reverse gear 63. When the sleeve 72 meshes with the piece gear portion of each gear, each gear is connected to the supported auxiliary shaft so as not to be relatively rotatable, and can rotate integrally. Further, when the sleeve 72 slides in the axial direction, a synchro ring (not shown) is urged to a gear to be connected, and the rotation speed of the gear is synchronized with the rotation speed of the auxiliary shaft, and then each gear and the auxiliary shaft are Can be connected.

  As described above, the first shift mechanisms 70a and 70c shift the rotational driving force transmitted to the first input shaft 11 to establish an odd gear. Similarly, the second shift mechanisms 70b and 70d shift the rotational driving force transmitted to the second input shaft 12 to establish an even gear. That is, the first input shaft 11, the drive gears 41, 43, 45, the driven gears 51, 53, 55, and the first shift mechanisms 70 a, 70 c constitute a transmission mechanism of a system that establishes an odd gear. Yes. The second input shaft 12, the drive gears 42, 44, 46, the driven gears 52, 54, 56, and the second shift mechanisms 70b, 70d constitute a transmission mechanism of a system that establishes an even-numbered shift stage. Yes. In the dual clutch transmission 1, the dual clutch 30 is controlled by the transmission control device 80, and the rotational driving force is disengaged and engaged with the transmission mechanism divided into two systems.

  The shift control device 80 exchanges information with each other by ECU 3 and CAN (Controller Area Network) communication, and performs a shift control of the transmission 1 based on a shift command from the ECU 3, acquired vehicle information, and the like. ). Therefore, the shift control device 80 outputs a control command to the operation mechanisms of the first shift mechanisms 70a and 70c and the second shift mechanisms 70c and 70d to operate them, and connects the driven gear and the countershaft that constitute a predetermined shift stage. The state and the connection release state are switched. Furthermore, the transmission control device 80 outputs a control command to the actuator of the dual clutch 30 to control the disconnected state and the connected state of the first clutch 31 and the second clutch 32.

  In addition, the shift control device 80 according to the present embodiment waits for execution of the shift control for a standby time for the purpose of suppressing the occurrence of a busy shift in which the shift control cannot be immediately started in response to the shift command. I do. Therefore, when the shift command is sent from the ECU 3, the shift control device 80 calculates the shift time required for the shift control according to the shift command and the next command time from the present until the next shift command is sent. calculate. Then, when the shift time is longer than the next command time, the shift control device 80 executes standby control that waits for execution of the shift control for the standby time.

  In this embodiment, this standby time is set as follows. The shift control device 80 first calculates the next command time based on the vehicle speed and the change rate of the accelerator opening when the shift command is sent. Furthermore, the shift control device 80 calculates a shift time required for shift control according to the shift command that is currently being sent. This shift time may include the time until the shift control is completed if the shift control is currently being performed. Then, the transmission control device 80 sets the standby time to be equal to or longer than the next command time and equal to or shorter than the shift time.

  When the next command time is calculated to be longer than the shift time, it can be estimated that the next shift command is sent after the shift to the required shift speed is completed. Therefore, the shift control device 80 executes the shift control to the required shift stage without setting the standby time to 0 or performing the standby control. Details of this standby control will be described later.

(Shift control by the shift control device 80)
The shift control by the shift control device 80 will be described with reference to FIG. As described above, the transmission control device 80 of the transmission 1 controls the dual clutch 30, the first shift mechanisms 70a and 70c, and the second shift mechanisms 70b and 70d, so that the ECU 3 sends out based on the shift map data. The shift control according to the received shift command is executed. Further, as shown in FIG. 2, the shift map data has shift lines L <b> 1 to L <b> 5 that are lines representing the relationship between the accelerator opening and the vehicle speed. As the shift map data, there are data for upshift and data for downshift.

  Further, the dual clutch type transmission 1 having the above-described configuration has previously established (pre-shifted) a shift stage to be shifted in a transmission mechanism to which rotational driving force is not transmitted during traveling of the vehicle. When a command is sent, high-speed shift control is realized by switching the engagement state of the clutch of each transmission mechanism. Similarly, there are an up-preshift type and a down-preshift type. Here, a case where downshift shift control is executed with reference to the shift map data having the downshift shift line will be described as an example.

  When a vehicle state including a driver's operation and a traveling state changes so as to cross the shift line on the shift map data, a shift command is sent. For example, when the vehicle speed is reduced because the vehicle is approaching a slope while the accelerator opening is kept constant and the vehicle is traveling at the sixth speed, the vehicle state straddles the shift line L5 and the regions D6 to D5. Transition to. Then, a shift command for setting the requested shift speed to the fifth speed is sent from the ECU 3. As described above, the required shift speed (fifth speed to first speed) according to the shift command sent from the ECU 3 differs depending on the areas D5 to D1 to which the vehicle state has changed.

  Further, the transmission 1 performs a pre-shift that preliminarily establishes a gear stage that is scheduled to be shifted in a transmission mechanism that does not transmit rotational driving force while the vehicle is traveling, based on shift map data having a pre-shift line for down-preshift. Is going. That is, in the above example, the fifth speed stage is established in advance before the vehicle state transitions to the region D5 in a transmission mechanism different from the transmission mechanism that establishes the sixth speed stage. And when the shift command which makes a request | requirement gear stage 5th speed stage is sent, the engagement state of the dual clutch 30 is switched and it changes to a request | requirement gear stage. As described above, the dual clutch type automatic transmission having the dual clutch 30 uses the preshift to speed up the shift change.

  By the way, in an automatic transmission including a dual clutch type, a further shift command may be sent while executing a shift control according to the shift command depending on a vehicle state including a driver's operation. This is because the vehicle state has changed over a plurality of areas on the shift map data in a short time. Then, depending on the timing at which the shift command is sent, a busy shift state is entered in which the shift control cannot be immediately started in response to the shift command. In such a case, the automatic transmission performs shift control that shifts to a gear position that corresponds to the preceding shift command and then shifts to a gear position that corresponds to the subsequent shift command.

(Standby control by transmission control device 80)
The standby control by the transmission control device 80 will be described with reference to FIGS. Here, as shown in FIG. 3, the case of downshifting from the sixth speed to the third speed is illustrated. Further, the shift control device 80 performs the downshift control by calling a control program for executing processing as shown in FIG. 4 every short period (for example, 6 [ms]). First, when the driver depresses the accelerator while traveling at the sixth speed, the accelerator opening increases, and as shown in FIG. 3, a shift command requesting the fifth speed is sent at time t1.

  Then, the shift control device 80 determines whether or not the shift control to the requested shift stage is currently executable (S101). This is because if the shift control or the preshift control based on the previously issued shift command is being executed, the shift control cannot be executed immediately, so whether or not the shift control can be executed is determined in S101. Here, the transmission 1 is in a state where the pre-shift to the fifth speed is completed during traveling at the sixth speed (S101: Yes).

  Next, the shift control device 80 calculates the step between the current shift speed (sixth speed) and the required shift speed (fifth speed) (S102). Here, since the level difference is calculated as one level, it is determined that there is a level difference (S103: Yes) in the determination of whether or not there is a level difference (S103). This is a shift command for requesting the current shift speed depending on the vehicle state when a plurality of shift commands are sent, so the presence or absence of a step is determined in S103. If the step is 0 (S103: No), a process for resetting the timer and standby control flag F used for standby control is performed (S105), and the control program is terminated.

  Subsequently, the shift control device 80 acquires from the ECU 3 the accelerator opening and the preset threshold Th when the shift command is sent. The accelerator opening may be detected when the shift command is sent, and may be detected during the period from when the shift control device 80 receives the command signal to the present time. Here, it is assumed that the accelerator opening is below the threshold Th (S201: Yes), and the shift control device 80 proceeds to calculation of the next command time Pn.

  The above-mentioned threshold value Th is a reference value provided for the accelerator opening in order to determine whether or not standby control needs to be performed. When the accelerator opening exceeds this threshold Th, it is determined that further accelerator depression cannot be expected, and execution of standby control is suppressed. That is, when the accelerator opening is equal to or greater than the threshold value Th (S201: No), the standby control is terminated without starting the standby control or is continued, and the shift control by the transmission control device 80 is performed. The process is started (S104).

  Next, the shift control device 80 calculates the next command time Pn until the next shift command is sent based on the vehicle speed and the change rate of the accelerator opening when the shift command is sent (S202). Therefore, the shift control device 80 first estimates the time at which the next shift command requesting the fourth speed is sent, taking into account the transition of the vehicle state on the shift map data. Then, the next command time Pn is calculated from the difference from the time when the shift command is sent to the time.

  More specifically, for example, an intersection of a curve indicating the vehicle state change characteristic obtained from the change speed of the vehicle speed and the change speed of the accelerator opening and the shift line L4 is obtained. Then, when the accelerator opening increases from the current accelerator opening at the above change speed, the time required to reach the accelerator opening at the intersection of the shift line L4 is calculated as the next command time Pn. Further, in order to make the calculation of the next command time Pn easier, it may be configured such that the change characteristic of the vehicle state is approximated by a straight line, or the vehicle speed is regarded as constant.

  Furthermore, the shift control device 80 calculates a shift time Ps required for shift control according to the shift command that is currently being sent (S203). That is, the shift control device 80 calculates the time required for the shift control from the current sixth speed to the fifth speed as the shift time Ps. The shift time Ps varies depending on the current shift speed, the required shift speed, the pre-shift state, and the like, and can be calculated in consideration of such information. Here, since the pre-shift to the fifth gear is completed, it is calculated as a relatively short shift time.

  Subsequently, the shift control device 80 compares the calculated next command time Pn with the shift time Ps (S204). Here, when the shift time Ps is longer than the next command time Pn, the transmission 1 may not be able to immediately start executing the shift control in response to the next shift command (occurrence of a busy shift). is assumed. That is, in S204, it can be said that it is determined whether or not a busy shift is made when the next shift command is sent by comparing the next command time Pn and the shift time Ps.

  Here, it is assumed that the transmission 1 can perform high-speed shift change using pre-shift, and the next command time Pn is longer than the shift time Ps (S204: No), and the shift control by the shift control device 80 is started. (S104). After that, since the shift control is started, the above-described timer and standby control flag F are reset (S105), and the control program is terminated. Then, the shift control based on the shift command to the fifth gear that was sent first at time t2 ends.

  As described above, when the next command time Pn is longer than the shift time Ps (S204: No), the next shift command is sent after the shift to the required shift speed (fifth speed) is completed. Can be estimated. In other words, when the shift control to the current required shift stage is started, the shift control is completed earlier than the next shift command is sent, so that a busy shift occurs even if the next shift command is sent. Will not.

  Next, in a state in which the driver continues to depress the accelerator, the accelerator opening increases at the same changing speed as at time t1, and as shown in FIG. 3, the shift requesting the fourth speed at time t3. A command is sent out. Then, the shift control device 80 determines again whether the shift control to the currently requested shift speed (fourth speed) can be executed (S101). Here, since the shift control to the fifth gear is finished, it is assumed that the next shift control can be executed (S101: Yes). Then, the shift control device 80 calculates the step between the current shift speed (fifth speed) and the required shift speed (fourth speed) (S102). Here, similarly, the level difference is calculated as one level, and it is determined that there is a level difference (S103: Yes).

  Subsequently, the shift control device 80 compares the accelerator opening at the time of transmission of the shift command with the threshold Th (S201). Here, it is assumed that the accelerator opening is below the threshold Th (S201: Yes), and the shift control device 80 proceeds to calculation of the next command time Pn (S202). The shift control device 80 estimates the time at which the next shift command for requesting the third speed is sent, taking into account the transition of the vehicle state on the shift map data, as before. Then, the next command time Pn is calculated from the difference from the time when the shift command is sent to the time.

  Furthermore, the shift control device 80 calculates a shift time Ps required for shift control according to the shift command that is currently being sent (S203). That is, the shift control device 80 calculates the required time as the shift time Ps when performing shift control from the current fifth speed to the fourth speed. Here, since the transmission 1 is immediately after the shift to the fifth speed, the shift time Ps is compared with the shift control using the first pre-shift from the sixth speed to the fifth speed. become longer.

  Then, the shift control device 80 compares the calculated next command time Pn with the shift time Ps again (S204). Here, since the shift time Ps has become longer than the previous time, the next command time Pn is assumed to be shorter than the shift time Ps (S204: Yes), and the process proceeds to the standby control. In other words, when the shift control to the fourth speed stage is started, a busy shift is assumed at the time when the shift command requesting the third speed stage is sent, so the shift control to the fourth speed stage is executed. Wait.

  Next, based on the standby control flag F, it is determined whether standby control is currently being performed (S205). Here, since standby control has not yet started (S205: Yes), a standby time Pw is set (S301). The shift control device 80 sets a time obtained by adding a predetermined margin time to the next command time Pn as the standby time Pw. This allowance time allows an error in the calculated next command time Pn, and is set in advance. The standby time Pw is set to be equal to or shorter than the shift time Ps.

  Then, the transmission control device 80 starts a timer and sets a standby control flag F (S304), and ends the control program. As described above, the shift control apparatus 80 completes the shift control to the fifth speed and starts the shift control based on the already-described shift command (fourth speed). Each condition (S103, S201) , In step S204, standby control for waiting for execution of the shift control is performed. Before standby control is started and the next shift command is sent, the process proceeds from (S101) to (S103: Yes), and then proceeds from (S201) to (S204: Yes). In S205, it is determined that standby control is being performed. (S205: No).

  Then, the transmission control device 80 compares the timer with the standby time Pw (S206), and if it is shorter than the standby time Pw (S206: Yes), the control program is terminated and the standby control is continued. In S206, the reason why the timer and the standby time Pw are compared is that the standby control is interrupted and the shift control based on the previously described shift command is started. That is, it is assumed that the next shift command is not transmitted due to a change in the vehicle state, etc., although it is estimated that the next shift command is transmitted during the standby time Pw.

  Thereafter, in a state in which the driver continues to depress the accelerator, the accelerator opening increases at the same changing speed as at time t3, and as shown in FIG. 3, the shift requesting the third speed at time t4. A command is sent out. Then, the shift control device 80 determines again whether the shift control to the currently requested shift speed (third speed) can be executed (S101). Here, as described above, since the shift control to the fifth speed has been completed, the next shift control can be executed (S101: Yes). Then, the shift control device 80 calculates the step between the current shift speed (fifth speed) and the required shift speed (third speed) (S102). Here, the level difference is calculated as two levels, and it is determined that there is a level difference (S103: Yes).

  Thereby, the shift control apparatus 80 shifts to (S201) to (S204). Here, when the accelerator opening is equal to or greater than the threshold value Th at time t4 due to the depression of the accelerator by the driver (S201: No), the standby control is terminated and the shift control by the shift control device 80 is started. (S104). Further, the next command time Pn until the next shift command for requesting the second speed is sent, and the shift time Ps required for shifting from the current fifth speed to the third speed are calculated again ( (S202, S203) and the two are compared (S204). Here, it is assumed that there is a certain period until the next shift command requesting the second gear is sent. Then, since the next command time Pn is shorter than the shift time Ps (S204: No), it is determined that a busy shift is assumed not to occur, and the shift control by the shift control device 80 is started. (S104).

  As described above, when the shift command is sent at time t4, it is determined that it is appropriate to start the shift control from the current fifth speed to the third speed, and this shift control is started. It was supposed to be. On the other hand, depending on the state of the vehicle, it is also assumed that the next shift command for requesting the second gear is sent during a shorter time than the newly calculated shift time Ps. In such a case, the standby control is continued by resetting the standby time Pw, and the shift from the fifth speed to the second speed is performed after the shift command to the second speed is issued. You may make it perform control.

  Finally, the shift control device 80 starts shift control to the requested shift speed (third speed) based on the shift command (S104). Then, a process for resetting the timer and the standby control flag F is performed (S105), and the standby control and the control program are ended. The shift control from the fifth speed to the third speed is a shift that immediately starts the shift control in response to the shift command that requests the third speed sent at time t4. Then, the shift is completed at time t5 through the control of the second shift mechanism 70d and the dual clutch 30 by the transmission control device 80, the synchronization control of the second input shaft 12, and the like.

(Effect of embodiment)
According to the dual-clutch transmission 1 described above, when the shift time Ps is long compared with the next command time Pn, that is, when a busy shift is assumed to occur, the shift control is executed only for the standby time Pw. It was assumed that standby control to wait for was performed. As a result, when a shift command is sent during the standby time Pw as expected, the shift control device 80 can immediately start executing shift control according to the newly sent shift command. Then, it is possible to shift to the final required shift stage by one shift control with respect to the shift command sent over a plurality of times. Therefore, the occurrence of busy shift can be suppressed, and the number of shifts can be reduced to reduce the load on the clutch mechanism and shift mechanism.

  Here, a case where standby control is not performed in the exemplified vehicle state will be described. As shown by the broken line in FIG. 3, the shift control device ends the shift control based on the shift command to the fifth gear that is sent first at time t2. Therefore, when a shift command requesting the fourth speed is sent at time t3, shift control from the fifth speed to the fourth speed is started. After that, a shift command requesting the third gear is sent at time t4. However, since the shift control is being performed, a busy shift is generated in which the shift control cannot be immediately executed with respect to this shift command. At time t4-2, the shift control to the fourth speed is completed, and from this time, the shift control to the third speed is started according to the previously described shift command. If standby control is not performed, the shift is completed at time t5-2. As described above, when the standby control is performed and when the standby control is not performed, the number of shift control operations can be reduced, and the time required for completing the shift can be finally shortened.

  Further, the shift control device 80 calculates the next command time Pn based on the vehicle speed and the change rate of the accelerator opening when the shift command is sent. Since the timing for sending the next shift command varies based on the vehicle state and map data, it is possible to estimate the time when the command is sent from the vehicle speed and the changing speed of the accelerator opening. Thereby, the next command time Pn from the present until the next shift command is sent can be calculated with high accuracy. Therefore, the shift control device 80 can more reliably determine whether or not standby control for waiting for execution of the shift control is necessary.

  Furthermore, the shift control device 80 sets the standby time Pw to be equal to or longer than the next command time Pn and equal to or shorter than the shift time Ps. Thereby, it is possible to suitably set the standby time Pw for waiting for execution of the shift control. Here, it is assumed that the vehicle state changes while waiting for execution of the shift control for the standby time Pw, and that no further shift command is sent within the standby time Pw. Even in such a case, by suitably setting the standby time Pw, it is possible to promptly shift to the shift control based on the currently transmitted shift command. Therefore, the time loss due to waiting of the waiting time Pw can be reduced.

  The shift control device 80 waits to execute shift control on condition that the shift time Ps is longer than the next command time Pn and that the accelerator opening at the time of transmission of the shift command is smaller than a preset threshold value. The standby control is executed. The standby control by the shift control device 80 is executed assuming that the next shift command is sent within the standby time Pw. The next shift command is sent in accordance with the vehicle state based on the map data. However, particularly when the accelerator is stepped on, the accelerator opening increases and is easily sent within a short time. On the other hand, if the accelerator opening is greater than or equal to a predetermined value, in order to respond to the driver's acceleration request, control is often performed so that the engine speed is increased at the current shift stage without performing a shift, and the accelerator pedal is further depressed. Since the increase cannot be expected, it is difficult to send the next shift command. Therefore, with the above configuration, it is possible to more reliably determine whether or not standby control is necessary.

<Modification of Embodiment>
In the present embodiment, the transmission 1 has been described as a dual clutch automatic transmission. On the other hand, the present invention can be applied to any automatic transmission having three or more speeds, even if it is not a dual clutch type. Even in this case, the standby time Pw can be set by calculating the next command time Pn and the shift time Ps in the automatic transmission to be applied, thereby suppressing the occurrence of busy shift and reducing the number of shifts.

  Further, in this embodiment, the case where the downshift is performed from the fifth speed to the third speed is exemplified as the standby control by the speed change control device 80. On the other hand, the same standby control can be executed regardless of the shift control at any gear stage. Furthermore, standby control can be executed in the same manner even when the shift control has one or more steps. However, in consideration of the configuration and specifications of the transmission 1, the necessity of standby control may be determined so that standby control is not performed when the level difference becomes two or more. More specifically, for example, in S103, the presence or absence of a step is determined in S103. However, it may be determined that the process proceeds to S201 only when the step is one step. As a result, it is possible to respond to the driver's acceleration orientation by executing the shift control to the required required shift stage. However, when the purpose is to suppress the occurrence of the busy shift and reduce the number of shifts, the mode exemplified in this embodiment is preferable.

  Further, in the present embodiment, the standby time Pw is set by adding a margin time to the next command time Pn. On the other hand, it is good also as a structure which sets to the fixed time set beforehand, or calculates from an accelerator opening or its change speed. Similarly, the next command time Pn may be simply obtained from the map based on the accelerator opening or its changing speed.

1: Transmission, 2: Engine (prime mover), 3: ECU
11: First input shaft, 12: Second input shaft, 21: First counter shaft, 22: Second counter shaft, 30: Dual clutch (clutch mechanism)
31: 1st clutch, 32: 2nd clutch 41-46: Drive gear of shift stage 51-56: Driven gear of shift stage, 52a: Small diameter gear 61, 62: Final reduction gear, 63: Reverse gear, 64: Ring gear 65: Parking gears 70a, 70c: First shift mechanism, 70b, 70d: Second shift mechanism 71: Hub, 72: Sleeve 80: Shift control device

Claims (4)

An input shaft rotatably supported by the case;
A clutch mechanism for transmitting the rotational driving force of the prime mover to the input shaft;
A shift mechanism that selectively establishes a plurality of shift stages for shifting the rotational driving force transmitted to the input shaft;
A shift control device that operates the shift mechanism and switches the engagement state of the clutch mechanism when a shift command is sent, and executes shift control according to the shift command;
When the shift command is sent, the shift control device calculates a shift time required for the shift control according to the shift command and a next command time from the present to the next shift command being sent, An automatic transmission that waits for execution of the shift control for a waiting time when the shift time is longer than the next command time. In claim 1,
The shift control device is an automatic transmission that calculates the next command time based on a vehicle speed and a change speed of an accelerator opening when the shift command is transmitted. In claim 1 or 2,
The shift control device is an automatic transmission in which the standby time is set to be longer than the next command time and shorter than the shift time. In any one of Claims 1-3,
The shift control device, when the shift command is sent, when the shift time is longer than the next command time and the accelerator opening at the time of sending the shift command is smaller than a preset threshold value. An automatic transmission that waits for execution of the shift control.

Images