JP2008232356A - Automatic transmission device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic transmission device for estimating the loaded condition of a vehicle without using a load sensor. <P>SOLUTION: The automatic transmission device computes a load energy amount to be loaded on a friction engaging means in starting the vehicle (S12), calculates a vehicle speed change amount C from a vehicle speed in the non-engaging condition of the friction engaging means (S54) and a vehicle speed in the following engaging condition (S61) during shift operation after starting the vehicle, estimating the loaded condition of the vehicle in accordance with the load energy amount and the vehicle speed change amount, and controls the shift operation of a transmission depending on the estimated loaded condition of the vehicle. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an improvement of an automatic transmission.

As a conventional automatic transmission, there is a technique for calculating a load energy amount applied to a clutch at the time of starting, and setting a gear ratio at the time of starting according to the load energy amount (see Patent Document 1).
JP 2005-351327 A

  In such a conventional technique, in order to improve the calculation accuracy when calculating the amount of load energy, when considering the weight of the vehicle, it is necessary to newly provide a load sensor, which means an increase in cost and an increase in weight. There's a problem.

  The present invention has been made in view of the above-described problems, and provides an automatic transmission that estimates the loading state of a vehicle without using a load sensor and shifts based on the estimated loading state. Objective.

  According to a first aspect of the present invention, there is provided an automatic transmission including a transmission that performs a shift by switching a gear that transmits engine rotation. The automatic transmission is disposed between the engine and the transmission, and the transmission is switched when the gear is switched. Friction engaging means for temporarily interrupting transmission of the rotation of the engine to the gear, and shift control for controlling the shift of the transmission by controlling switching of the gears and switching of the engagement state of the friction engaging means And a vehicle speed detecting means for detecting the speed of the vehicle, wherein the shift control means includes a load energy amount calculating means for calculating a load energy amount applied to the friction engagement means when the vehicle starts, and after the vehicle starts. Vehicle speed change amount detection means for calculating a change amount of the vehicle speed from the vehicle speed in the non-engaged state of the friction engagement means and the vehicle speed in the subsequent engagement state, and the load energy amount and the previous And a loading state estimating means for estimating the loading state of the vehicle based on the vehicle speed change is an automatic transmission which performs shift control of the transmission in accordance with the loading state of the estimated vehicle.

  According to a second invention, in the first invention, when the shift control means has the load energy amount smaller than a load energy amount predetermined value and the vehicle speed change amount is within a range of the vehicle speed change amount predetermined value, When the load state of the vehicle is determined to be a light load state and the load energy amount is equal to or greater than the load energy amount predetermined value or the vehicle speed change amount is not within the range of the vehicle speed change amount predetermined value, the vehicle load state Is an automatic transmission that determines a constant load state heavier than the light load state.

  According to a third aspect, in the second aspect, the shift control means is configured such that the load energy amount is smaller than the load energy amount predetermined value and the vehicle speed change amount is within a range of the vehicle speed change amount predetermined value. Is an automatic transmission that determines that the loaded state of the vehicle is the lightly loaded state when is repeated a predetermined number of times.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the shift control means measures an elapsed time after starting, and if the elapsed time exceeds a first predetermined time, the loading state This is an automatic transmission that cancels the estimation of.

  According to a fifth invention, in any one of the first to fourth inventions, the shift control means is a time during which the shift gear selected by the driver is a non-running gear and the non-running gear is selected. Is an automatic transmission that determines that the vehicle is in a constant load state when the vehicle is over a second predetermined time.

  According to a sixth invention, in the first invention, when the shift control means shifts to a gear stage having a high gear ratio, the automatic transmission apparatus sets the engine speed at the time of shifting to be lower as the loading state of the vehicle is lighter. It is.

  In the first invention, since the loading state of the vehicle is estimated based on the load energy amount of the clutch and the vehicle speed change amount, it is not necessary to provide a load sensor for detecting the weight of the vehicle, and cost reduction and weight reduction are achieved. Can do.

  In the second and third inventions, the loading state of the vehicle can be accurately estimated.

  In the fourth invention, since the estimation of the loading state is stopped when the elapsed time after the start exceeds the first predetermined time, the road surface state changes after the start until the first predetermined time elapses. Can be prevented.

  In the fifth invention, when the elapsed time in the non-running gear is equal to or longer than a predetermined time, the vehicle loading state is estimated as a constant loading state. For example, when the vehicle stops for a long time due to loading, Since the shift control is performed in a constant loading state, the start performance can be ensured.

  In the sixth aspect of the invention, the lighter the vehicle is loaded, the lower the speed of the engine that changes gears is controlled, so that the fuel consumption can be improved.

  In FIG. 1, 1 is an engine, 2 is a friction clutch (friction engagement means), 3 is a synchronous mesh transmission, and the output shaft of the transmission 3 is a drive shaft (for example, via a propeller shaft (not shown)). , Rear axle).

  An electronic governor device 1A for controlling the fuel injection amount is provided in a fuel injection pump for supplying fuel to the engine 1, and a clutch booster 2A for operating the clutch 2 for transmitting the power of the engine 1 to the transmission 3 is provided. The transmission 3 is provided with a gear shift unit 3A for shifting a gear train constituting the transmission. Reference numeral 27 denotes a control valve of the clutch booster 2A, and 31 denotes an air tank, which supplies operating pressure (compressed air) to the actuators constituting the gear shift unit 3A and the clutch booster 2A.

  As shown in FIG. 2, the transmission 3 has a splitter gear train as a sub-transmission on the input side and output side of a main transmission gear train 40A (Zm1-Zc1 to Zm3-Zc3, ZmR-ZcR) as a main transmission. 40B (Zm4-Zc4, Zm5-Zc5) and range gear train 40C (Zr1-Zcr1, Zr2-Zcr2) are connected to each other. Hereinafter, the configuration of the transmission 3 will be described.

  A splitter gear Zm5 for switching the splitter gear train 40B to a high speed stage is freely arranged on the input shaft 42 for inputting the output of the engine 1, and a synchronizer hub 44A constituting the synchromesh mechanism 44 is provided at the tip thereof. Fixed. A main shaft 46 disposed coaxially with the input shaft 42 includes a splitter high gear Zm4, a third gear Zm3, a second gear Zm2, a first gear Zm1 and a reverse gear ZmR that constitute each gear stage of the main transmission gear train 40A. Are arranged freely to rotate, and a range high gear Zr1 for switching the range gear train 40C to a high speed stage is fixed to the tip thereof. A synchronizer hub 44A constituting the synchromesh mechanism 44 is fixed to the main shaft 46 on which the splitter high gear Zm4, the third speed gear Zm3, the second speed gear Zm2, the first speed gear Zm1, and the reverse gear ZmR are arranged.

  On the other hand, the main counter shaft 48 arranged in parallel with the input shaft 42 and the main shaft 46 has a counter that is always meshed with the splitter low gear Zm5, the splitter high gear Zm4, the third speed gear Zm3, the second speed gear Zm2, and the first speed gear Zm1. Splitter gear Zc5, counter drive gear Zc4, counter third speed gear Zc3, counter second speed gear Zc2 and counter first speed gear Zc1 are fixed. A counter reverse gear ZcR that is always meshed with the reverse gear ZmR is fixed to the main counter shaft 48 via a reverse idler gear ZmR1.

  A range low gear Zr2 for switching the range gear train 40C to a low speed stage is freely arranged on the output shaft 50 that is coaxially arranged with the main shaft 46 and is connected to a propeller shaft (not shown), and has a synchromesh at one end thereof. A synchronizer hub 44A constituting the mechanism 44 is fixed. A range counter high gear Zcr1 and a range counter low gear Zcr2, which are always meshed with the range high gear Zr1 and the range low gear Zr2, are fixed to the range counter shaft 52 arranged in parallel with the output shaft 50, respectively.

  As shown in FIG. 2, the transmission 3 includes main gear trains Zm1-Zc1 to Zm3-Zc3, ZmR-ZcR (third forward speed, first reverse speed) of the main transmission, and a split gear of the sub-transmission disposed on the engine side. Rows Zm4-Zc4, Zm5-Zc5 (low L, simply L, high H, H), range gear rows Zr1-Zcr1, Zr2-Zcr2 (H, L) of the sub-transmission similarly disposed on the propeller shaft side 12 steps forward (minimum) by switching the main gear trains Zm1-Zc1 to Zm3-Zc3, switching the split gear trains Zm4-Zc4, Zm5-Zc5, and switching the range gear trains Zr1-Zcr1, Zr2-Zcr2. 1L on the speed side to 6H on the fastest side).

  As shown in FIG. 3, the gear shift unit 3A selects the synchromesh mechanism 44 of the main gears Zm3 to ZmR inside the gear shift unit 3A, and has two positions of gear insertion (gear set) and gear release (neutral) with respect to the main gears Zm3 to ZmR. A main actuator (not shown) for switching to a split actuator, a split actuator (see FIG. 3) for switching the synchromesh mechanism 44 for split gears Zm5 and Zm4 to two positions, low and high, and a synchromesh mechanism 44 for range gears Zr1 and Zr2. And a range actuator (see FIG. 3) that switches between two positions, low and high.

  In the case of FIG. 3, air cylinders 76 and 77 are used as the range actuator and the split actuator. The synchromesh mechanism 44 of the range gears Zr1 and Zr2 is engaged with the piston rod 76a of the air cylinder 76, and the on / off of the back pressure and the on-after processing are processed in addition to the range switching by the ON / OFF of the electromagnetic valves MVRL and MVRH. The synchromesh mechanism 44 of the split gears Zm5 and Zm4 is engaged with the piston rod 77a of the air cylinder 77, and on-off processing is performed in addition to switching the splitter by turning on and off the electromagnetic valves MVSH and MVSL. 78a is a range low switch, 78b is a range high switch, 79a is a split low switch, and 79b is a split high switch. These are part of a gear position switch for detecting the shift position of the transmission 3. Constitute.

  The input shaft 42 is connected to the main counter shaft 48 via the splitter low gear Zm5 when the synchromesh mechanism 44 of the splitter gears Zm5 and Zm4 is at the L position. Similarly, when the synchromesh mechanism 44 is at the H position, the input shaft 42 is connected to the splitter high gear Zm4. To the main countershaft 48. The main counter shaft 48 is connected to the main shaft 46 via the main gear Zm3, Zm2, Zm1, or ZmR when one of the synchromesh mechanisms 44 of the main gears Zm3 to ZmR is in the gear engagement position. The main shaft 46 is directly connected to the output shaft 50 when the synchromesh mechanism 44 of the range gears Zr1 and Zr2 is at the H position. Similarly, when the synchromesh mechanism 44 is at the L position, the range high gear Zr1, the range counter shaft 52, and the range low gear Zr2 It is connected to the output shaft 50 via

  As shown in FIG. 1, as a detection means required for vehicle shift control, an engine rotation speed sensor 29 that detects an engine rotation speed, and an accelerator opening that detects the amount of depression of an accelerator pedal 7 (a required amount of an accelerator opening). Sensor 28, clutch stroke sensor 22 for detecting the stroke position of clutch 2, shift position of transmission 3 (selected positions of split gear trains Zm4-Zc4, Zm5-Zc5, main gear trains Zm1-Zc1 to Zm3-Zc3, ZmR-ZcR) Gear position switch (incorporated in the gear shift unit 3A) for detecting the selected position, range gear train Zr1-Zcr1, Zr2-Zcr2), a vehicle speed sensor 21 for detecting the rotational speed from the output shaft of the transmission 3, For detecting the rotation speed of the main counter shaft from the main gear Zm1 of the machine 3 Down counter shaft rotation speed sensor 23, range counter shaft rotation speed sensor 17 for detecting the rotational speed of the range counter shaft from the range gear Zr1 of the transmission 3 is provided.

  In order to switch between automatic control of engagement control of the clutch 2 and manual control based on the manual operation of the driver, clutch pedal switches 24 and 25 for detecting an initial position (release state) and an operating position (depression state) of the clutch pedal are provided. It is done. A shift lever unit 4 is provided in the cab as a shift instruction means of the transmission 3 and outputs a shift instruction signal (including a neutral instruction signal) corresponding to the shift position of the shift lever 4A. In addition, a switch 5 (mode changeover switch) for selecting a manual shift mode in which the vehicle is shifted according to the driver's shift instruction and an automatic shift mode that is automatically performed according to the driving state is shifted. Provided on the knob of the lever 4A. The cab is provided with a display unit 13 for displaying the shift position of the transmission 3 and the like, and a brake pedal switch 26 for detecting depression of a brake pedal (not shown). 13A is an alarm means (for example, a buzzer).

  The transmission control unit (TCU, transmission control means) 11 and the engine control unit (ECU) 12 are responsible for the transmission control, and these are connected by serial communication (LAN). In the TCU 11, when the mode changeover switch 5 is in the manual shift mode, the shift lever unit 4 shifts to the target position corresponding to the shift instruction signal when the shift instruction signal of the shift lever unit 4 does not match the shift position based on the gear position switch of the transmission 3. A shift request (shift command) is generated. When the mode changeover switch 5 is in the automatic shift mode, a target stage is obtained from a detection signal of the accelerator opening sensor 28 and a detection signal of the vehicle speed sensor 21 based on a preset shift map, and this target stage is the gear of the transmission 3. When it does not coincide with the shift position based on the position switch, a shift request (shift command) to the target stage is generated.

  The shift control is activated by the generation of these shift requests, and the TCU 11 and the ECU 12 control the electronic governor device 1A, the clutch booster 2A, and the gear shift unit 3A in order to smoothly perform the gear shift to the target position at that time. In FIG. 2, split gear trains Zm4-Zc4, Zm5-Zc5 are switched from L to H or H to L each time the transmission 3 changes gear by gear, while range gear trains Zr1-Zrc1, Zr2-Zcr2 The transmission 3 is switched from L to H or from H to L only when the transmission 3 shifts from 1L to 2H to 3L to 6H or vice versa.

  For shift control that does not involve switching of the range gear trains Zr1-Zrc1, Zr2-Zcr2, when a shift command (shift request) is generated, the accelerator opening of the engine 1 (rack position of the fuel injection pump) is reduced to a no-load state. Then, the clutch 2 is disconnected. When the disconnection of the clutch 2 is detected, the main gear trains Zm1-Zc1 to Zm3-Zc3 are set to neutral (gear disengagement), and at the same time the split gear trains Zm4-Zc4 and Zm5-Zc5 are switched, while the engine rotation is performed. Control is performed to target rotation (synchronous rotation of the gear stage to be geared of the main transmission) calculated from the rotation of the range counter shaft and the gear ratio (ratio) after completion of the transmission of the transmission 3. In accordance with this, the main gear train corresponding to the shift command is controlled while the clutch 2 is controlled to the target rotation by the double clutch operation (clutch disengagement → clutch engagement → clutch disengagement). Gearing to Zm1-Zc1 to Zm3-Zc3 is performed. Thereafter, when the gear engagement is completed, the clutch 2 is connected and the engine rotation control is switched to normal control corresponding to the accelerator opening.

  The transmission 3 to which the present invention is applied is configured as described above. Next, the configuration of the TCU 11 of the present invention will be described using the block diagram shown in FIG.

  The operating state of the engine and the transmission 3 is input to the TCU 11 from each sensor. Specifically, the rotational speed of the engine 1 is input from the engine rotational speed sensor 29, and the fuel injection amount for detecting the output torque of the engine 1 is input from the ECU 12. The rotational speed of the main counter shaft 48 is input from the main counter shaft rotational speed sensor 23, the accelerator opening is input from the accelerator opening sensor 28, and the shift lever position is input from the gear position switch (3A). A signal of the gear position sensor 62 that detects the position of the fixed gear of the splitter gear train 40B is input. Further, an output signal of the vehicle speed sensor 21 that detects the wheel speed of the vehicle and an output signal of the clutch stroke sensor 22 that detects the engagement state of the clutch 2 are input.

  Based on each input signal, the TCU 11 performs switching control of the transmission 3 by switching the split gear train and the range gear train and switching the engagement state of the clutch 2. Furthermore, the loading state of the vehicle is detected based on these input signals.

  Next, a loading state detection method performed by the TCU 11 of the present invention will be described with reference to FIGS.

  The loading method detection method of the present invention corresponds to the amount of load energy acting on the clutch 2 at the time of automatic start and the change in wheel speed at the time of shifting from the non-engaged state to the engaged state at the time of shifting after the start. The loading state of the vehicle is determined on the basis of the gradient of the travel path determined in this way. Hereinafter, the loading state detection method of the present invention will be described with reference to the drawings.

  FIG. 5 is a flowchart for determining whether or not the automatic start control can be performed. First, in step S1, it is determined whether or not the current gear stage is a predetermined gear stage that may determine the loaded state. If there is, the rotational speed of the main countershaft 48 is read from the main countershaft rotational speed sensor 23 in step S2, and it is determined whether or not the detected rotational speed is less than a first predetermined value for determining that the running state of the vehicle is stopped. judge. Here, the gear stage that may determine the loaded state is preferably a gear stage having a long shift time.

  If the rotation speed of the main countershaft 48 is less than the first predetermined value in step S2, it is determined that the vehicle is stopped, the automatic start is enabled and the automatic start flag is turned on in step S3. Since the vehicle is running and automatic start is impossible, the process proceeds to step S4, and the automatic start flag is turned off. Even if the gear position determination at step S1 is not an automatic startable gear position, the process proceeds to step S4.

  FIG. 6 is a flowchart for determining the load energy acting on the clutch 2 during the automatic start control. First, in step S11, the accelerator opening is read from the accelerator opening sensor 28, and whether the accelerator opening is equal to or greater than a second predetermined value. Determine. Since the accelerator opening is small when the vehicle travels on a downhill, it is determined whether the travel road is a flat road (not downhill) from determining whether the accelerator opening is equal to or greater than a second predetermined value.

  If it is a flat road, the process proceeds to step S12. In step S12, the clutch load energy amount acting on the clutch 2 at the time of automatic start is calculated and compared with a third predetermined amount. The clutch load energy amount can be calculated from the fuel injection amount, the engine rotational speed, and the rotational speed of the input shaft 42 as described in, for example, Japanese Patent Application Laid-Open No. 2005-351327 filed by the present applicant. Further, in this step S12, the magnitude of the clutch load energy is determined by comparison with one predetermined value. However, the vehicle loading state described later may be determined more finely by comparing with a plurality of predetermined values.

  If it is less than the third predetermined amount in step S12, the process proceeds to step S13 to determine whether or not the automatic start flag is on. If the automatic start flag is on, it is determined in step S14 that the load of the clutch 2 is small, that is, the load amount of the vehicle is small (light load state), and the load flag is set to on.

  On the other hand, if the determination condition is not satisfied in step S11, step S12, and step S13, the process proceeds to step S15, the load flag is set to OFF, and the process proceeds to step S16.

  In step S16 following step S14, the first counter that measures the elapsed time from the end of the automatic start control is cleared, and the control ends.

  Therefore, in the flowchart of FIG. 6, the load energy of the clutch 2 is calculated and compared with the third predetermined value, so that the loading state of the vehicle is discriminated between the light loading state and the other state (constant loading state). Can do.

  FIG. 7 to FIG. 9 are flowcharts for determining the gradient of the traveling road surface based on a change in wheel speed during the shift at the time of the shift after the automatic start.

  In the flowchart of FIG. 7, it is first determined whether or not the load flag is on in step S41, and if it is on, it is determined whether or not automatic start control is being performed in step S42. When the automatic start control is not being performed, the process proceeds to step S43.

  In subsequent step S43, the first counter is incremented, and the process proceeds to step S44 to determine whether or not the count number of the first counter is less than a seventh predetermined value. Here, the seventh predetermined value is a value corresponding to a time when the probability that a change in the road surface may occur during traveling is high. That is, in step S44, it is determined that when the time of the seventh predetermined value has elapsed from the end of the automatic start control, the road surface state, for example, the friction coefficient changes, so that it is impossible to determine the wheel speed change to be performed.

  If the first counter is less than the seventh predetermined value in step S44, the process proceeds to step S47. If the first counter is greater than the seventh predetermined value, the process proceeds to step S45, the load flag is turned off in step S45, and the first counter is cleared in the subsequent step S46. To finish the control. In addition, also when conditions are not satisfied by determination of step S41, S42, it progresses to step S46.

  On the other hand, in step S47, it is determined whether or not a shift from the gear stage at the time of starting to the next predetermined gear stage is started. If so, the process proceeds to step S49, and in step S49 and subsequent step S50. The first and second wheel speed flags are set to off. In step S51 following step S50, it is determined whether or not the target gear stage after the shift is a predetermined gear stage capable of determining the loaded state. If it is a predetermined gear, the process proceeds to step S48 in FIG. 8, and if it is not a predetermined gear, the process returns to step S45, and the load flag is set to OFF. Also, if it is determined in step S47 that the shift is not started, the process proceeds to step S48.

  Here, the first wheel speed flag is a flag that is set when the wheel speed when the clutch 2 is not engaged is already detected in the shift after starting, and the second wheel speed flag is the shift after starting. The flag is set when the wheel speed when the clutch 2 is engaged is already detected.

  In step S48 of FIG. 8, it is determined whether or not the first wheel speed flag is off. If it is off, the process proceeds to step S52. If it is on, the process proceeds to step S57, and the fourth counter is incremented. Here, the fourth counter is the elapsed time from the disengaged wheel speed of the clutch 2 to the engaged wheel speed at the time of shifting after the start. If the fourth counter is incremented in step S57, the process proceeds to step S58.

  On the other hand, in step S52, the engagement state of the clutch 2 is determined. If the clutch 2 is not engaged, the process proceeds to step S53, and if not, the process proceeds to step S58.

  In step S53, the stroke amount of the clutch 2 is read from the clutch stroke sensor 22, and it is determined whether or not the stroke amount is equal to or greater than an eighth predetermined value. Here, the eighth stroke amount is a stroke amount at which the clutch 2 can be determined to be in the disengaged state. If the stroke amount is greater than or equal to the eighth predetermined value, the process proceeds to step S54, and if it is less than the eighth predetermined value, the process proceeds to step S58.

  If the stroke amount is equal to or greater than the eighth predetermined value, it can be determined that the clutch 2 is in the disengaged state, and in step S54, the first wheel speed, which is the wheel speed when the clutch 2 is not engaged, is read. In subsequent step S55, the first wheel speed flag is set to ON, and in step S56, the fourth counter is cleared.

  Therefore, in steps S48 and S52 to S57, the wheel speed when the clutch 2 is not engaged (first wheel speed) is detected at the time of shifting from the gear stage at the start to the next target gear stage. From S58 to step S62, the wheel speed (second wheel speed) in the engaged state of the clutch 2 at the time of shifting is detected.

  In step S58, it is first determined whether or not the second wheel speed flag is off. If it is off, the wheel speed at the time of engagement of the clutch 2 has not been detected, and it is determined in step S59 whether or not the clutch 2 is engaged. If the engaging operation is being performed, it is determined in step S60 whether or not the stroke of the clutch 2 is less than a ninth predetermined value. If the stroke amount is less than the ninth predetermined value, it is determined that the clutch 2 is in the engaged state, the process proceeds to step S61, and the second wheel speed, which is the wheel speed when the clutch 2 is engaged, is calculated. In step S62, the second wheel speed flag is set to ON, and the process proceeds to step S63 shown in FIG.

  If the determination conditions in steps S58 to S60 are not satisfied, the process proceeds to step S63 in FIG.

  In step S63 to step S70 shown in FIG. 9, it is determined whether or not the change in the wheel speed when the clutch 2 is changed from the non-engaged state to the engaged state during the shift is within a predetermined value range.

  In step S63, it is determined whether the first wheel speed flag is on. If it is on, the process proceeds to step S64, and in step S64, it is determined whether the second wheel speed flag is on. If it is on, the first and second wheel speeds have been calculated, and the process proceeds to step S65, where the wheel speed change amount C per unit time is calculated from the first and second wheel speeds and the fourth counter.

  Then, it is determined by comparing with the tenth and eleventh predetermined values whether or not the change amount C of the wheel speed calculated in the subsequent steps S66 and S67 is within a predetermined range. Here, the tenth predetermined value is a predetermined value for determining a downhill, a positive value is set, and the eleventh predetermined value is an uphill determination value, and a negative value is set. If the wheel-side change amount C is an uphill, the wheel speed should be decelerated and becomes a negative value. If the wheel side change is a downhill, the wheel speed increases, so the change amount C is a positive value. If the change amount C exceeds the range set by the tenth and eleventh predetermined values, it is determined that the vehicle is traveling on a slope, and if it is within the range, it is determined that the vehicle is traveling on a flat road.

  If the change amount C is within the predetermined range, the process proceeds to step S68, the second counter is incremented, and the process proceeds to step S69. On the other hand, if the change amount C is not within the predetermined range, the process proceeds to step S69. Here, the second counter counts the number of times that the condition that the clutch load energy at the time of automatic start is smaller than the third predetermined value and the change amount C of the wheel speed is within the predetermined range is satisfied.

  In step S69, the load flag is set to OFF, and in step S70, the first counter is cleared and the control is terminated.

  Accordingly, in the flowcharts shown in FIG. 7 to FIG. 9, the wheels in the disengaged state of the clutch 2 and the subsequent engaged state at the time of the shift after the start when the load energy amount of the clutch 2 is less than the third predetermined value. The speed is detected, the amount of change C per unit time is calculated from the wheel speed, and when the amount of change C is within a predetermined range, it is determined that the traveling road surface of the vehicle is a flat road and is out of range. In the case, it is determined that the road is a slope.

  FIG. 10 is a flowchart for determining the loading state of the vehicle.

  First, in step S21, it is determined whether the count number of the second counter is equal to or greater than a fourth predetermined value. If the count number is greater than or equal to the fourth predetermined value, the process proceeds to step S22, where it is determined that the loading state of the vehicle is lightly loaded, for example, less than half of the allowable loading load of the vehicle, and in this case, the lightly loaded flag is set on. Proceed to S24. If it is less than the fourth predetermined value, the light load flag is set to OFF in step S23 (the constant load flag, which is a flag in the case of a constant load state in which the vehicle load exceeds half), is set, and the process proceeds to step S24.

Therefore, the loading state of the vehicle is determined based on the determination condition of step S21. When the count number of the second counter is equal to or greater than a fourth predetermined value, it is determined that the vehicle is lightly loaded. In step S24, it is determined whether the count value of the third counter is equal to or greater than a fifth predetermined value. Here, the third counter is a counter that measures the time when the shift position of the shift lever is the shift position in the non-traveling state and the vehicle is stopped. The fifth predetermined value is, for example, about 15 minutes.

  If it is greater than or equal to the fifth predetermined value, the process proceeds to step S25, and the light load flag is set to OFF. This is considered to be a state of loading when the vehicle has been stopped for a long time, so it is determined not as a lightly loaded state but as a fixedly loaded state, and in steps S27 and S28, second, third Clear the counter and end control.

  If the condition is not satisfied in step S24, the process proceeds to step S26, and it is determined whether or not the current gear is a non-traveling gear such as neutral. If it is a non-traveling gear stage, it will progress to step S29, a wheel speed will be read, and it will be determined whether a wheel speed is below a 6th predetermined value. Here, the sixth predetermined value is a predetermined value for determining that the vehicle is stopped, and is, for example, a value of about 5 km / h.

  If the condition of step S29 is satisfied, the process proceeds to step S30, where the count number of the third counter is incremented and the control is terminated. If the conditions of steps S26 and S29 are not satisfied, the process proceeds to step S31, the count number of the third counter is cleared, and the control is terminated.

  Therefore, in step S24 to step S31, if the vehicle is stopped and the stop time is equal to or greater than the fifth predetermined value, it is determined that the vehicle is loaded and the constant load flag is set to ON. At the next start after the vehicle stops, the start control as a constant loading state is performed, and the start performance is ensured.

  In this way, it is possible to estimate the loading state of the vehicle without using a load sensor, thereby reducing the cost and weight, and in the case of a light loading state, a higher gear than in the case of a constant loading state. In the case of shifting to a ratio, by setting the engine speed at the time of shifting to a low value, it is possible to improve fuel efficiency while ensuring start performance.

  The present invention is not limited to the above-described embodiment, and it is obvious that various modifications can be made within the scope of the technical idea.

It is a schematic block diagram of the system of this embodiment. It is a block diagram of a transmission. It is a block diagram of a range actuator and a splitter actuator. It is a block diagram of a control unit. It is a flowchart which determines the propriety of implementation of automatic start control of vehicles. It is a flowchart which determines the load energy which acts on the clutch at the time of automatic start control. It is a flowchart which determines the gradient of a driving | running | working road surface based on the change of the wheel speed in shifting at the time of the shift after an automatic start. It is a flowchart which determines the gradient of a driving | running | working road surface based on the change of the wheel speed in shifting at the time of the shift after an automatic start. It is a flowchart which determines the gradient of a driving | running | working road surface based on the change of the wheel speed in shifting at the time of the shift after an automatic start. It is a flowchart which determines the loading state of a vehicle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 2 Clutch 2A Clutch booster 3 Transmission 3A Gear shift unit 4 Shift lever unit 4A Shift lever 11 Transmission control unit 12 Engine control unit 21 Vehicle speed sensor 22 Clutch stroke sensor 23 Main counter shaft rotation speed sensor 24 Clutch pedal switch 28 Accelerator opening Degree sensor 29 Engine rotation speed sensor 40A Main transmission gear train 40B Splitter gear train 40C Range gear train 42 Input shaft 44 Synchromesh mechanism 44A Synchronizer hub 46 Main shaft 48 Main counter shaft 50 Output shaft 52 Range counter shaft 62 Gear position sensor

Claims (6)

In an automatic transmission including a transmission that changes speed by switching a gear that transmits engine rotation,
Friction engagement means disposed between the engine and the transmission and temporarily interrupting transmission of the rotation of the engine to the transmission when the gear is switched;
Shift control means for controlling the shift of the transmission by controlling the switching of the gears and the engagement state of the friction engagement means;
Vehicle speed detecting means for detecting the speed of the vehicle,
The shift control means includes
Load energy amount calculation means for calculating a load energy amount loaded on the friction engagement means when the vehicle starts,
Vehicle speed change amount detecting means for calculating the amount of change in vehicle speed from the vehicle speed in the non-engaged state of the friction engagement means and the vehicle speed in the subsequent engaged state at the time of shifting after the vehicle starts;
Loading state estimation means for estimating a loading state of a vehicle based on the load energy amount and the vehicle speed change amount;
An automatic transmission that performs shift control of the transmission according to the estimated loading state of the vehicle.   The shift control means determines that the load state of the vehicle is a light load state when the load energy amount is smaller than a load energy amount predetermined value and the vehicle speed change amount is within a range of the vehicle speed change amount predetermined value, When the load energy amount is equal to or greater than the load energy amount predetermined value or the vehicle speed change amount is not within the range of the vehicle speed change amount predetermined value, the vehicle loading state is determined to be a constant loading state heavier than the light loading state. The automatic transmission according to claim 1.   The shift control means is configured such that when the load energy amount is smaller than the load energy amount predetermined value and the vehicle speed change amount is within the predetermined range of the vehicle speed change amount, the vehicle load state is repeated a predetermined number of times. The automatic transmission according to claim 2, wherein the automatic transmission is determined to be in a lightly loaded state.   4. The shift control means according to claim 1, wherein the shift control means measures an elapsed time after the start and stops estimating the loading state when the elapsed time exceeds a first predetermined time. The automatic transmission according to one.   The shift control means determines the loading state of the vehicle when the shift gear selected by the driver is a non-traveling gear and the non-traveling gear is selected for a second predetermined time or longer. The automatic transmission according to any one of claims 1 to 4, wherein the automatic transmission device is determined to be in a loaded state.   2. The automatic transmission according to claim 1, wherein, when shifting to a gear stage having a high gear ratio, the shift control means sets the engine speed at the time of shifting to be lower as the loading state of the vehicle is lighter.

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