Method and apparatus for controlling transmission of vehicle

Abstract

The present invention relates to a method and apparatus for controlling a transmission of a vehicle and, more particularly, to a method and apparatus for controlling synchronization of a synchronizer included in a transmission. The method includes determining a speed change mode of a vehicle and a target time corresponding to the speed change mode; calculating a difference in speed between an input shaft and an output shaft with respect to a current time; calculating a speed increment or decrement of the output shaft from the current time to the target time; calculating a synchronization torque using the difference in speed and the speed increment or decrement; determining a target displacement of a synchronizer using the synchronization torque; and controlling the synchronizer according to the target displacement and recognizing a sleeve with a clutch gear.

Claims

1. A method for controlling a transmission comprising: determining a speed change mode of a vehicle and a target time corresponding to the speed change mode; calculating a difference in speed between an input shaft and an output shaft with respect to a current time; calculating a speed increment or decrement of the output shaft from the current time to the target time; calculating a synchronization torque using the difference in speed and the speed increment or decrement; determining a target displacement of a synchronizer using the synchronization torque; and controlling the synchronizer according to the target displacement and recognizing a sleeve with a clutch gear.

2. The method according to claim 1, further comprising: detecting a synchronization gradient between the sleeve and the clutch gear; comparing the synchronization gradient and a target gradient and determining a calibration value; and applying the calibration value to the target displacement.

3. The method according to claim 1, wherein, when the speed change mode is an acceleration mode, the synchronization torque is determined by Equation 1: $\begin{array}{cc}{T}_{\mathrm{cone}}=\frac{+{}_{\mathrm{accel}}}{t}{J}_{\mathrm{eq},n},& \mathrm{Equation}1\end{array}$ wherein T.sub.cone denotes the synchronization torque, denotes the difference in speed, .sub.accel denotes the speed increment, t denotes a difference between the target time and the current time t1, and J.sub.eq,n denotes equivalent inertia for engagement of gear step n.

4. The method according to claim 1, wherein, when the speed change mode is a deceleration mode, the synchronization torque is determined by Equation 2: $\begin{array}{cc}{T}_{\mathrm{cone}}=\frac{-{}_{\mathrm{decel}}}{t}{J}_{\mathrm{eq},n},& \mathrm{Equation}2\end{array}$ wherein T.sub.cone denotes the synchronization torque, denotes the difference in speed, .sub.decel denotes the speed decrement, t denotes a difference between the target time and the current time t1, and J.sub.eq,n denotes equivalent inertia for engagement of gear step n.

5. The method according to claim 1, wherein the synchronizing comprises: converting the target displacement into a target control position of an actuator for driving the synchronizer; and controlling the actuator according to the target control position and moving the synchronizer to the target displacement.

6. An apparatus for controlling a transmission, the apparatus comprising: a calculator configured to determine a speed change mode of a vehicle and a target time corresponding to the speed change mode, calculate a difference in speed between an input shaft and an output shaft with respect to a current time, calculate a speed increment or decrement of the output shaft from the current time to the target time, and calculate a synchronization torque using the difference in speed and the speed increment or decrement; and a controller configured to determine a target displacement of a synchronizer using the synchronization torque, and control the synchronizer according to the target displacement and recognizing a sleeve with a clutch gear.

7. The apparatus according to claim 6, wherein the controller detects a synchronization gradient between the sleeve and the clutch gear, compares the synchronization gradient and a target gradient and determining a calibration value, and applies the calibration value to the target displacement.

8. The apparatus according to claim 6, wherein, when the speed change mode is an acceleration mode, the synchronization torque is determined by Equation 1: $\begin{array}{cc}{T}_{\mathrm{cone}}=\frac{+{}_{\mathrm{accel}}}{t}{J}_{\mathrm{eq},n},& \mathrm{Equation}1\end{array}$ wherein T.sub.cone denotes the synchronization torque, denotes the difference in speed, .sub.accel denotes the speed increment, t denotes a difference between the target time and the current time t1, and J.sub.eq,n denotes equivalent inertia for engagement of gear step n.

9. The apparatus according to claim 6, wherein, when the speed change mode is a deceleration mode, the synchronization torque is determined by Equation 2: $\begin{array}{cc}{T}_{\mathrm{cone}}=\frac{-{}_{\mathrm{decel}}}{t}{J}_{\mathrm{eq},n},& \mathrm{Equation}2\end{array}$ wherein T.sub.cone denotes the synchronization torque, denotes the difference in speed, .sub.decel denotes the speed decrement, t denotes a difference between the target time and the current time t1, and J.sub.eq,n denotes equivalent inertia for engagement of gear step n.

10. The apparatus according to claim 6, wherein the controller converts the target displacement into a target control position of an actuator for driving the synchronizer, and controls the actuator according to the target control position and moving the synchronizer to the target displacement.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a block diagram illustrating a transmission control apparatus according to an embodiment of the present invention.

(2) FIG. 2 illustrates control of a transmission in an acceleration situation according to an embodiment of the present invention.

(3) FIG. 3 illustrates control of a transmission in a deceleration situation according to an embodiment of the present invention.

(4) FIG. 4 is a flowchart illustrating a method for controlling a transmission according to an embodiment of the present invention.

DETAILED DESCRIPTION

(5) The aforementioned advantages, objects, and features of the invention will be set forth in detail with reference to the accompanying drawings such that those skilled in the art can easily practice the present invention. In describing the present invention, a detailed description of well-known technologies will be omitted if it is determined that such description can unnecessarily obscure the main points of the present invention. Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. It should be understood that the present invention is not limited to the following embodiments, and that the embodiments are provided for illustrative purposes only. The scope of the invention should be defined only by the accompanying claims and equivalents thereof.

(6) FIG. 1 is a block diagram illustrating a transmission control apparatus according to an embodiment of the present invention.

(7) Referring to FIG. 1, a transmission control apparatus 102 according to an embodiment includes a calculator 104 and a controller 106. The calculator 104 determines a speed change mode of the vehicle and a target time corresponding to the speed change mode, and calculates a difference in speed between an input shaft and an output shaft with respect to the current time. In addition, the calculator 104 calculates a speed increment or decrement of the output shaft from the current time to a target time and calculates a synchronization torque using the difference in speed and the speed increment or decrement of the speed.

(8) The controller 106 determines a target displacement of a synchronizer 108 using the synchronization torque calculated by the calculator 104, and controls the synchronizer 108 according to the determined target displacement to synchronize a sleeve and a clutch gear. In this embodiment, the controller 106 may detect a synchronization gradient between the sleeve and the clutch gear, determine a calibration value by comparing the detected synchronization gradient and the target gradient, and calibrate the target displacement of the synchronizer 108 by applying the determined calibration value to the target displacement.

(9) In addition, according to the embodiment, the controller 106 may convert the determined target displacement into a target control position of an actuator for driving the synchronizer 108, and the actuator may be controlled according to the target control position to move the synchronizer 108 to the target displacement.

(10) Hereinafter, a method for controlling a transmission according to an embodiment of the present invention will be described in detail with reference to FIGS. 2 to 4.

(11) Referring to FIG. 4, the calculator 104 determines a speed change mode according to a command for speed change from the driver (402). Herein, speed change modes are divided into an acceleration mode and a deceleration mode. FIG. 2 illustrates a process of speed change performed when the speed change mode is the acceleration mode, and FIG. 3 illustrates a process of speed change performed when the speed change mode is the deceleration mode. Thereafter, the calculator eight 104 determines a target time t2 according to the determined speed change mode (402).

(12) Next, the calculator 104 calculates a difference in speed between an input shaft and an output shaft with respect to the current time t1 (404). For example, in FIGS. 2 and 3, the difference in speed between the input shaft and the output shaft with respect to the current time t1 is indicated by .

(13) Next, the calculator 104 calculates a speed increment or decrement (the amount of increase in speed or the amount of decrease in speed) of the output shaft from the current time t1 to the target time t2 (406). In FIG. 2, the speed increment of the output shaft from the current time t1 to the target time t2 is indicated by .sub.accel. In FIG. 3, the speed decrement of the output shaft from the current time t1 to the target time t2 is indicated by .sub.decel.

(14) Next, the calculator 104 calculates a synchronization torque using the calculated speed difference and the speed increment or decrement (.sub.accel or .sub.decel) (408). If the speed change mode is the acceleration mode as shown in FIG. 2, the synchronization torque may be calculated by Equation 1 given below.

(15) $\begin{array}{cc}{T}_{\mathrm{cone}}=\frac{+{}_{\mathrm{accel}}}{t}{J}_{\mathrm{eq},n}& \mathrm{Equation}1\end{array}$

(16) In Equation 1, T.sub.cone denotes the synchronization torque, denotes the difference in speed between the input shaft and the output shaft, .sub.accel denotes the speed increment, t denotes the difference between the target time t2 and the current time t1, and J.sub.eq,n denotes equivalent inertia for engagement of gear step n.

(17) If the speed change mode is the acceleration mode as shown in FIG. 3, the synchronization torque may be calculated by Equation 2 given below.

(18) $\begin{array}{cc}{T}_{\mathrm{cone}}=\frac{-{}_{\mathrm{decel}}}{t}{J}_{\mathrm{eq},n}& \mathrm{Equation}2\end{array}$

(19) In Equation 2, T.sub.cone denotes the synchronization torque, denotes the difference in speed between the input shaft and the output shaft, .sub.decel denotes a speed decrement, t denotes the difference between the target time t2 and the current time t1, and J.sub.eq,n denotes equivalent inertia for engagement of gear step n.

(20) The controller 106 determines a target displacement of the synchronizer 108 using the calculated synchronization torque (410). Then, the controller 106 synchronizes the sleeve and the clutch gear by controlling the synchronizer 108 according to the determined target displacement (412). In this operation, the controller 106 may convert the determined target displacement into a target control position of an actuator for driving the synchronizer 108, and move the synchronizer 108 to the target displacement by controlling the actuator according to the target control position.

(21) Although not shown FIG. 4, the controller 106 may detect a synchronization gradient during synchronization between the sleeve and the clutch gear, and determine a calibration value by comparing the detected synchronization gradient and a target gradient. The controller 106 may calibrate the target displacement by applying the determined calibration value to the target displacement of the synchronizer 108.

(22) Those skilled in the art will appreciate that various substitutions, modifications, variations can be made to the present invention without departing from the technical spirit of the invention and that the present invention is not limited to the embodiments described above and the accompanying drawings.